REVISTA PĂDURILOR
REVISTĂ TEHNICO-ȘTIINȚIFICĂ EDITATĂ DE SOCIETATEA „PROGRESUL SILVIC”
Redactor responsabil:
prof. dr. ing. Stelian Alexandru Borz
Colegiul de redacție
Membri:
prof. dr. ing. loan Vasile Abrudan
dr. ing. Adam Crăciunescu
prof. dr. ing. Alexandru Lucian Curtu
conf. dr. ing. Mihai Daia
s. 1. Gabriel Duduman
prof. dr. ing. Ion I. Florescu
ing. Olga Georgescu
acad. prof. Victor Giurgiu
prof. dr. ing. Sergiu Horodnic
dr. ing. Maftei Leșan
dr. ing. Ion Machedon
dr. ing. Gheorghe Mohanu
dr. ing. Romică Tomescu
Fotografii copertă:
Copertă față și spate exterior:
© Paul Condurache.
Copertă interioară:
© Universitatea Transilvania din Brașov
ISSN: 1583-7890
Varianta on-line:
www. revistapadurilor. ro
ISSN 2067-1962
Indexare în baze de date:
CABI
DOAJ
Google Academic
Index Ccpemicus (1D 7538)
RePEc
SC1PIO
CUPRINS
(Nr. 1/2017)
Stelian Alexandru Borz: Ediția aniversară de 50 de ani
a Simpozionului Internațional de Mecanizare Forestieră,
Brașov, România, 25 - 29 septembrie 2017 ........... 3
Kazuhiro Aruga : Balanța economică și emisiile de gaze cu efect
de seră relaționale cu utilizarea biomasei forestiere în zona
Kanuma, Tochigi, Japonia............................ 5
Marius Cheța, Daniel Șerban, Gheorghe Ignea, Rudolf
Alexandru Derczeni, Victor Sfeclă, Stelian Alexandru Borz:
Utilizarea senzorilor de măsurare a nivelului de presiune
acustică la monitorizarea performanțelor ferăstraielor circulare
acționate manual: ce parametri pot fi estimați și în ce măsură
pot fi aceștia estimați? ............................... 15
Enda Coates, Brian Cronin, Cristopher Mcguren, Nicholas
Mockler, Maeve Kennealy, Eleanor Owens, Tom Kent: Irish
Wood Fuel Database - O bază de date WEB pentru parametrii
combustibililor lemnoși...................................... 23
Mădălina Fornea : Unealtă M.S. Excel - V.B.A. pentru procesarea
și analiza datelor de natură posturală în operații forestiere ... 29
Majid Lotfalian, Mahboobe Sabzi, Ah Hosseini Yekani, Saba
Peirov: Utilizarea PERT și CPM în planificarea operațiilor
forestiere ............................................... 40
Iulian Mihai Nenu: Hartă interactivă a carierelor de piatră și a
balastierelor din România: Posibilități de utilizare a materialelor în
construcția de drumuri forestiere............................ 49
Reproducerea parțială sau totală a articolelor sau ilustrațiilor poate fi făcută
cu acordul redacției revistei. Este obligatoriu să fie menționat numele autorului
și al sursei. Articolele publicate de Revista pădurilor nu angajează decât
responsabilitatea autorilor lor.
2017
CONTENT
(Nr. 1/2017)
	Stelian Alexandru Borz: 50th Anniversary of the International Symposium on Forestry Mechanization, Brașov, Romania, 25th - 29th September 2017	 3 Kazuhiro Aruga : Economic Balances and GHG Emissions of Forest Biomass Utilization in Kanuma Area of Tochigi Prefecture, Japan 	 5 Marius Cheța, Daniel Șerban, Gheorghe Ignea, Rudolf Alexandru Derczeni, Victor Sfeclă, Stelian Alexandru Borz: Using Sound Pressure Sensors to Monitor the Performance of Manually Operated Circular Saws: What Parameters and to What Extent Can They Be Inferred?	 15 Enda Coates, Brian Cronin, Cristopher Mcguren, Nicholas Mockler, Maeve Kennealy, Eleanor Owens, Tom Kent: Irish Wood Fuel DataBase - A WEB Based DataBase of Wood Fuel Parameters 	 23 Mădălina Fornea: A New M.S. Excel - V.B.A. Tool for Postural Data Processing and Analysis in Forest Operations 	 29 Majid Lotfalian, MahBooBe Sabzi, Aii Hosseini Yekani, SaBa
REVISTA	Peirov: Application of PERT & CPM for Forest Utilization Planning 	 40
PĂDURILOR	Iulian Mihai Nenu : Map of Stone Quarries and Gravei Pits
1886	in Romania: PossiBilities to Use the Materials in Forest Road Construction	 49
2017
131 ANI
2
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
50th Anniversary of the International
Symposium on Forestry
Mechanization, Brașov, Romania,
25th _ 29* September 2017
Stelian Alexandru BORZ
Intro
In the context of the Paris COP21 agreement
that calls for a more environmental friendly
and climate-resilient economy, Transilvania
University of Brașov - Faculty of Silviculture
and Forest Engineering is pleased to host
the Jubilee Edition of the International
Symposium on Forestry Mechanization
(FORMEC) between 25th and 29th September
2017, in Brașov (Romania).
Building up on the previous experience of the
Forest Engineering Community, and following
the 48th and 49th FORMEC editions held in Austria
and Poland, the motto of the conference is:
officials from countries worldwide to share
state-of-the-art knowledge and debate the most
criticai issues on how innovation should enhance
sustainable wood mobilization and forest value
chain competitiveness.
This year, the conference addresses key topics,
such as timber logging and transport, forest
road engineering, use of biomass for bioenergy,
ergonomics and work safety of forest operations
and other wood supply chain challenges, including
innovative forest equipment and emerging forest
technology.
Held for the first time in Romania, the
symposium is organized in two days of technical
sessions that will address new developments in
Remembering the 49th FORMEC Conference, Warsaw, Poland, 2016. © formec.org
“Innovating the competitive edge: from
research to impact in the forest value chain”
The 50th FORMEC anniversary brings together
leading researchers, practitioners and high-level
forest engineering, followed by one-day field trip
in the Romanian forests - FOREST ROMANIA
FAIR - to watch tradițional and innovative
harvesting technology at work.
Changing the lead between the FORMEC
organizers. © formec.org
Remembering the lst FOREST ROMANIA FAIR
Revista pădurilor • Anul 132 • 2017 • Nr. 1
3
Organizers
Transilvania University of Brașov - Faculty of
Silviculture and Forest Engineering, Department
of Forest Engineering, Forest Management
Planning and Terrestrial Measurements has
teamed up with the Forest Engineering Scientific
Community and Association for Development
and Innovation in Green Economy (ADIGE)
to organize the event. The opening ceremony,
plenary and technical sessions as well as the
poster session will be held in the facilities of the
Transilvania University of Brașov - Aula Sergiu T.
Chiriacescu.
Faculty of Silviculture and Forest Engineering,
Transilvania University of Brașov, host of the 50th
Symposium on Forestry Mechanization.
Attendance and contributions
More than 150 contributions were received
and will be presented during the event as oral
presentations and posters.
Scientists and practitioners coming from all
over the world will attend the jubilee edition
of the International Symposium on Forestry
Mechanization (FORMEC). A number of 30
countries will be represented by their scientists
and practitioners during the symposium, bringing
together the internațional high-lead Science,
experience and know-how.
Keynote speakers and support
High-level keynote speakers are expected to
participate and give presentations on current and
perspective topics related to forestry and forest
engineering, Science, technology, financing, and
forestry-related political agendas.
The event is supported by the local community,
național & internațional companie s and
organizations, associations and the state forest
management.
To support the anniversary edition of FORMEC,
four journals joined the partnership and will
release special numbers on the event’s topics:
Annals of Forest Research, Bulletin of the
Transilvania University of Brașov - Series
II - Forestry, Croatian Journal of Forest
Engineering and Revista Pădurilor - one of the
oldest forestry journals.
Looking forward for an excellent
event!
O FORMEC
Romania 2017
Univ.Prof.Dr.Eng. Stelian Alexandru BORZ
Department of Forest Engineering, Forest
Management Planning and Terrestrial Measurements,
Faculty of Silviculture and Forest Engineering,
Transilvania University of Brașov, Șirul Beethoven
No.l, 500123, Brașov, Romania,
President of the Organizing Committee,
FORMEC 2017
e-mail: stelian.borz@unitbv.ro
4
Revista pădurilor • Anul 132 • 2017 • Nr. 1
Economic Balances and GHG
Emissions of Forest Biomass
Utilization in Kanuma Area of
Tochigi Prefecture, Japan
1.	Introduction
Following the Great East Japan Earthquake, the
supply capacity of electricity has been reduced,
because the operation of many nuclear power
plants has been suspended. In this context, the
Japanese Government proposed to promote the
introduction in use of renewable energy sources
including biomass (***, 2012a). In August 2011, the
“Act on Purchase of Renewable Energy Sourced
Electricity by Electric Utilities” was adopted
in the Diet for the introduction of the “Feed-in
Tariff Scheme for Renewable Energy” starting
from July 2012. In the Feed-in Tariff (FIT), the
purchase price (without tax) of electricity sourced
by unused materials such as thinned wood and
logging residues was of 32 JPY/kWh, that sourced
by general materials such as sawmill residues
was of 24 JPY/kWh, and that sourced by recycled
material such as construction waste wood was
of 13 JPY/kWh (***, 2012b). Furthermore, a price
of 40 JPY/kWh for unused materials having a
generation capacity less than 2 MW was set in
order to promote the use of wood coming from
thinning operations and logging residues from a
large number of small, fragmented, and scattered
forests, starting with April of 2015. Incentives
have promoted the use of power generated
from unused materials, and they are expected
to increase the use of wood sourced by thinning
operations and logging residues from 2 million
m3 in 2014 to 8 million m3 in 2025 based on the
forest and forestry basic plan of Japan established
in May 2016 (Forestry Agency of Japan, 2016).
In order to utilize forest biomass resources for
bio energy, it is crucial to tind out the relationship
between the annual available amounts and the
procurement (harvesting and transporting) costs.
Yoshioka et al. (2005a), Kinoshita et al. (2009), and
Yamamoto et al. (2010) have carried out detailed
analyses of supply potențial based on Geographic
Information Systems (GIS).
Nord-Larsen and Talbot (2004), Aruga et al.
Kazuhiro ARUGA
(2006a), Rorstad et al. (2010), and Aruga et al.
(2011) discussed long-term feasibility of timber
and forest biomass resources by predicting
future forest resources using growth models
while optimizing the allocation of fuel wood
by Linear Programming or Random Search.
Yagi et al. (2007), Aruga et al. (2006b), and
Panichelli et al. (2008) discussed the scales and
locations of bio-energy facilities based on the
relationship between the supply potențial and the
procurement costs of forest biomass resources,
whereas Ranta (2005), Mbller and Nielsen (2007),
and Viana et al. (2010) developed methods for
expressing them at a național level. Furthermore,
Yamaguchi et al. (2010), Yamaguchi et al. (2014),
Nakahata et al. (2014), and respectively Aruga
and Uemura (2015) have developed a method to
estimate harvesting volumes and costs of logging
residues by considering the economical balances
estimated from revenues and costs of both timber
and logging residues in the region as a unit of
sub-compartments while Kinoshita et al. (2010)
and Kamimura et al. (2012) have developed
a similar method as a unit of cities and towns.
However, these studies have not considered the
regeneration expenses, which are important for
conducting the forest management, especially
in plantation forests such as Japanese cedar
and Japanese cypress from Japan. In contrast,
Aruga et al. (2014) developed a method to extract
production forests based on economic balances
that considered also the regeneration expenses.
Tlieir study defined the production forests as
those forests where the expected revenues surpass
all costs from planting to final harvesting. The
revenue and costs were estimated based on forest
registration and GIS data. However, the study just
estimated the annual available amount of forest
biomass resources with total revenues and costs
during a 60-year rotation. The estimation should
be conducted by considering the current situation
of forest resources, forestry, forest and energy
Industries and by projecting their future context
Revisia pădurilor • Anul 132 • 2017 • Nr 1
5
while discounting the future revenues and costs
to the present net values although the study of
Aruga et al. (2014) did not.
Therefore, this study estimated the annual
available amount of forest biomass resources from
profitable sub-compartments in Kanuma Area of
Tochigi Prefecture, Japan while considering the
regeneration expenses for the sustainability of
forest management and by discounting the future
revenues and costs to the present net values using
the long-term relationship between the supply
potențial and the procurement cost of forest
biomass resources established in a previous study
(Aruga et al., 2011). In addition to the economic
balances, this study estimated the greenhouse gas
(GHG) emissions including CO2, CH4, and N O
while the studies of Yoshioka et al. (2005b) and
Aruga et al. (2011) estimated only CO2 emissions.
2.	Materials and methods
2.1.	The General Approach
Forest biomass resources can be categorized
into several categories including logging
residues, wood sourced by thinning operations,
and broadleaved trees (Yoshioka et al., 2005a). GIS
layers of forest resource, slope, public and forest
roads were obtained from Tochigi Prefectural
Government in order to estimate the supply
potențial and the procurement costs of timber
and forest biomass resources.
In order to analyze the long-term relationship
between the supply potențial and the procurement
cost of timber and forest biomass resources, in
this study, future forest resources on each stand
were predicted using the system yield Table, Local
Yield Table Construction System (LYCS, Shiraishi
1985). Then, the stand harvesting schedules were
planned by balancing the supply potențial of
forest biomass resources using random search
while minimizing the procurement costs. Annual
available amounts of forest biomass resources
were estimated as the supply potențial from
profitable sub-compartments.
2.2.	Study Site
The site chosen for this study is located in
Kanuma area, consisting of Kanuma city and
Nishikata town (Aruga et al., 2011). This area
encompasses 52,000 hectares, of which about
65% are covered by forests. Most of forests
are man-made (79%) of which tree species are
conifers; Japanese cedar (Sugi) and Japanese
cypress (Hinoki) account for 54% and 23% of the
trees, respectively. Most of conifers are within
45-50 years old. As for the site slope, most of
forests are relatively steep, 30 degrees or more.
Tire density of the road network in the Kanuma
area is of 18 m/ha.
2.3.	Procurement Costs
Harvesting and transporting systems for
forest biomass resources were classified into
two types depending on the parts of a tree used
to recover energy wood (logging residues or
the whole tree sourced by thinning operations
and broadleaved trees). Logging residues are
considered as a byproduct of convențional
forestry while the wood coming from thinning
operations and broadleaved trees are assumed
to be felled for energy utilization. Therefore, the
system boundary of logging residues starts with
comminuting logging residues at the landing by
a mobile chipper while the system boundary of
thinning operations and broadleaved trees starts
with felling operations in the forests (Aruga et al.,
2011).
In this study, cable skidders, swing yarders,
tower yarders, and convențional yarders are
assumed to be used for the skidding/yarding
operations. Cable skidders could be used for
slopes below 11 degrees for uphill skidding and
for slopes below 19 degrees for downhill skidding.
In this study, one machine from the described
types is assumed to be selected for each stand so
that the skidding/yarding costs are minimized
within the topographic condition of each stand
(Aruga et al., 2011).
The harvesting and transporting costs of
timber and forest biomass resources were
estimated in relation to slope 0 (degree), average
stern volume V (m3/stem), harvested volumes per
ha V (m3/ha), the number of trees harvested per
ha Np (stem/ha), skidding/yarding distance L (m),
and transporting distance LT (m). In addition to
the direct costs of labor, machine, and fuel, the
indirect costs of labor (55% of the direct cost of
labor), machine moving cost (50,000 JPY/each),
overhead costs (14% of the total direct cost), piling
costs in the log market (700 JPY/m3), handlmg
fees associated with the logging contractor (5%
of timber and forest biomass prices) and the log
6
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
niarket (5% of timber prices), and consumption
tax (5% of the direct cost) are considered herein.
Thinning operations are subsidized in Japan.
In this study, subsidies were estimated using the
standard unit costs, areas, assessment coefficients,
and the subsidy rate of Tochigi Prefectural
Government (2010). Standard unit costs were
determined by age and thinning rates (Table 1).
Table 1
Standard unit costs (JPY/ha) for thinning operations
Age (year)	'Ihinning rate	
	Less than 30%	More than 30%
26-35	400,792	600,612
36-45	381,288	571,935
46-59	386,176	579,261
Tire assessment coefficient and the subsidy rate
were assumed to be 1.7 and 4/10, respectively. In
addition to subsidies given to conduct thinning
operations, subsidies to develop strip roads for
thinning operations are also received in Japan.
These subsidies were also estimated using standard
unit costs, areas, assessment coefficients, and the
subsidy rate of Tochigi Prefectural Government
(2010). Standard unit costs for construction of
strip roads were determined on slope categories
(Table 2).
Table 2
Standard unit costs for construction of strip roads
Slope	Standard unit costs (JPY/m)
< 5 degrees	159
6 to 10 degrees	191
11 to 15 degrees	230
16 to 20 degrees	276
21 to 25 degrees	477
26 to 30 degrees	850
In addition to these timber extraction
costs, regeneration expenses including site
preparation, planting, weeding, vine cutting,
pruning, and forest inventory were estimated
by labor expenses and the number of people
necessary in each operation, non-personnel
expenses, and Insurance expenses (Okawbata,
2003). Regeneration expenses were estimated as
2,512,376 JPY/ha for Japanese cedar and 2,892,365
JPY/ha for Japanese cypress, respectively. This
study considered the subsidy for regeneration.
Similar to the thinning operations, subsidies were
estimated using the standard unit costs, areas,
assessment coefficients, and the subsidy rate
of Tochigi Prefectural Government. Subsidies
were estimated as 1,227,400 JPY/ha for Japanese
cedar and 1,219,240 JPY/ ha for Japanese cypress,
respectively. Therefore, the net regeneration
expenses were estimated as 1,284,976 JPY/ha for
Japanese cedar and 1,673,125 JPY/ ha for Japanese
cypress, respectively.
2A. Revenues
Tire current supply potențial of timber and
forest biomass resources can be estimated from
the stern volume recorded in the forest register
and the coefficients such as the thinning ratio,
ratio of the top and branches’ volume to stern
volume, and tree density (Aruga et al., 2011). To
estimate the future available amounts of timber
and forest biomass resources, the yield system
Table, LYCS (Shiraishi, 1985) was applied to the
forest register. Time interval was set to five years.
In order to ensure a steady yet continuous work
of the energy conversion plants, forest biomass
resources should be steadily and continuously
supplied. In this study, the stand harvesting
schedules were planned for sixty years by
balancing the supply potențial of timber and
forest biomass resources using the random search
approach set to minimize the procurement costs
(Aruga et al., 2011). Revenues were estimated
using the supply potențial and log prices which
were set to 10,000 JPY/m3 and forest biomass
resources prices which were set to 3,000 JPY/
ton of dry matter (tDM). After the estimation of
revenues, the available amounts of forest biomass
resources from profitable sub-compartments
were also estimated. In addition to these figures,
sensitivity analyses were conducted with various
log prices such as 8,000 and 12,000 JPY/m3, and
forest biomass resources prices such as 6,000 and
10,000 JPY/tDM, respectively. Forest biomass
resources prices (6,000 JPY/tDM) were estimated
with the additional subsidy and an amount of
10,000 JPY/tDM was estimated according to the
FIT introduced in Japan.
2.5.	Economic Balances
Two types of energy-conversion technology
were considered in this study. One was the
direct combustion and the other was the small-
scale gasification (Aruga et al., 2011). Under the
Revisia pădurilor • Anul 132 • 2017 • Nr 1
7
FIT program, the price of electricity was set to
40 JPY/kWh for less than 2 MW produced and
32 JPY/kWh for more than 2 MW produced.
Furthermore, this study assumed that the steam
could be sold to houses at a price of 0.5 JPY/kg.
Then, the economic balances of direct combustion
and small-scale gasification were estimated.
2.6.	GHC Emissions
GHG emissions coming from all the processes
incurred the greatest costs with 15,325 JPY/tDM
(Aruga et al., 2011). However, by including the
subsidies and the regeneration costs, procurement
of such wood was the cheapest (6,960 JPY/tDM),
followed by logging residues (9,330 JPY/tDM).
Broadleaved forests incurred the greatest costs
with 13,143 JPY/tDM (Figure 1).
According to the supply potențial of forest
biomass resources including subsidies and
regeneration costs, logging residues were
Fig. 1. Procurement cost including the subsidies
of the system were examined using the method
described by Yoshioka et al. (2005b), Aruga et al.
(2011), and Ministry of the Environment (2005).
In addition to those described in Yoshioka et al.
(2005b) and Aruga et al. (2011), dismantlement of
a power generation plant was estimated as 5% of
the construction costs.
3.	Results and Discussions
3.1.	Economic Balances
Tire maximum supply potențial of forest
biomass resources was estimated to 28,872
tDM/year, which was enough to meet the fuel
requirement of a 5 MW direct combustion
power plant (Aruga et al. 2011). According to the
procurement costs of forest biomass resources
excluding the subsidies and regeneration costs,
logging residues were the cheapest (9,271 JPY/
tDM), followed by broadleaved forests (12,995
JPY/tDM); wood coming from thinning operations
assumed to be harvested based on the harvesting
schedule while the broadleaved forests and wood
sourced by thinning operations were assumed
to be harvested to meet sufficient volumes if
the forest biomass resources were not sufficient
(Figure 2).
The trend shown in Figure 2 was similar to the
results of a previous study (Aruga et al., 2011).
For timber, the maximum supply potențial and
the procurement cost were of 86,657 m3/year and
5,564 JPY/m3 without subsidies and regeneration
costs, while the same Figures were of 82,729
m3/year and 5,565 JPY/m3 with subsidies and
regeneration costs.
In a previous study (Aruga et al., 2011), the
average price of electricity sold to power grids in
Japan was assumed to be 8 JPY/kWh. Since the
generation costs specific to direct combustion
and small-scale gasification were more than
24 and 13 JPY/kWh, the economic balances of
electricity generation were in deficit. If the steam
8
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
30000
Fig. 2. Supply potențial with subsidy
could be sold to houses at a price of 0.5 JPY/kg,
the economic balance of small-scale gasification
would be positive whereas the economic balance
of direct combustion would remain negative
(Aruga et al., 2011).
Under the FIT program, the price of electricity
was set on 40 JPY/kWh for those plants producing
less than 2 MW and to 32 JPY/kWh for those
producing more than 2 MW.
Therefore, if the steam could be sold to houses
at a price of 0.5 JPY/kg, then the economic
balances of both direct combustion and small-
scale gasification would be positive (Figure 3).
The economic balances would be improved by
the subsidies, especially for direct combustion
in which the procurement costs contributed
significantly.
3.2.	Annual Availability cf Timber and Forest
Biomass Resources
With log prices set to 10,000 JPY/m3 and forest
biomass resources prices set to 3,000 JPY/tDM,
Fig- 3. Generation capacity and economic balance
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
9
the annual available amount of forest biomass
resources from profitable sub-compartments
including subsidies and regeneration costs was
estimated at 12,044 tDM/year.
It consisted of logging residues (3,999 tDM/
year) and thinned trees (8,045 tDM/year) as
shown in Table 3.
especially in the Kyushu Island (Tsuduki, 2006).
Therefore, sensitivity analyses were conducted to
discuss the effects of subsidies and regeneration
operations on the annual available amounts and
procurement costs of forest biomass resources.
Without subsidies and with regeneration costs,
the annual available amount of forest biomass
Table 3
Availability of forest biomass resources and timber and the procurement costs with and without subsidies
and regeneration costs for log prices of 10,000 JPY/m3 and forest biomass resources prices of 3,000 JPY/tDM
Subsidy	No Subsidy
Source	Regeneration	No Regeneration	Regeneration	No Regeneration
Total	12,044 tDM/year 6,571 JPY/tDM	15,056 tDM/year 6,161 JPY/tDM	2,710 LDM/year 8,531 JPY/tDM	6,022 tDM/year 8,510 JPY/tDM
Logging residues	3,999 tDM/year 8,010 JPY/tDM	4,484 tDM/year 8,216 JPY/tDM	2,068 tDM/year 7,897 JPY/tDM	5,107 tDM/year 8,148 JPY/tDM
Thinned Trees	8,045 tDM/year 5,856 JPY/tDM	10,572 tDM/year 5,290 JPY/tDM	642 tDM/year 10,577 JPY/tDM	915 tDM/year 10,531 JPY/tDM
Broadleaved Trees	0 tDM/year — JPY/tDM	0 tDM/year — JPY/tDM	0 tDM/year — JPY/tDM	0 tDM/year — JPY/tDM
Timber	57,003 m3/year 5,116 JPY/m3	63,958 m3/year 5,233 JPY/m3	29,470 m3/year 4,922 JPY/m3	72,830 m3/year 5,170 JPY/m3
With these prices, only 42% of maximum
supply potențial of forest biomass resources
was available and no broadleaved forests were
assumed to be harvested. Also, due to the limited
prices, the procurement cost of forest biomass
resources was reduced from 9,093 JPY/tDM (see
Figure 1) to 6,571 JPY/tDM (see Table 3) because
the procurement cost of logging residues was
reduced from 9,391 JPY/tDM to 8,010 JPY/tDM
and that of thinned trees was reduced from 6,711
JPY/tDM to 5,856 JPY/tDM.
For timber, the annual available amount and
the procurement cost were of 57,003 m3/year and
5,116 JPY/m3 respectively, accounting for 69%
and 92% of the maximum supply potențial and
procurement costs of timber.
Subsidies play important roles on economic
balances of regeneration and thinning
operations in Japan. However, subsidies would
be reduced due to limited budget of the Japanese
government. Since the revenues from clear
cutting operations cannot cover the regeneration
costs in the current conditions, forest owners
would not conduct planting operations even
on unsuitable natural regeneration sites after
clear cutting. This situation is spread in Japan,
resources from profitable sub-compartments was
estimated at only 2,710 tDM/year. It consisted of
logging residues (2,068 tDM/year) and the wood
sourced by thinning operations (642 tDM/year), as
shown in Table 3. Only 9% of the maximum supply
potențial of forest biomass resources was available.
No broadleaved forests and almost no wood
coming from thinning operations were harvested
in this scenario.
With these limited prices, the procurement
cost of forest biomass resources (8,531 JPY/tDM)
was higher than that with subsidies because
the procurement cost of wood coming from
thinning operations increased from 5,856 JPY/
tDM to 10,577 JPY/tDM while the cost of logging
residues without subsidies were similar to those
with subsidies. For timber, the annual available
amount and the procurement cost were also
reduced to 29,470 m3/year and 4,922 JPY/m3 due
to no subsidies for regeneration costs.
Without regeneration costs, the annual
available amount and the procurement cost
of timber were significantly higher, especially
without subsidies. Subsequently, the annual
available amount of logging residues was
higher. However, the increment was small with
10
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
subsidies. The annual available amount of wood
coming from thinning operations with subsidies
was increased whereas that without subsidies
was decreased significantly. Therefore, it was
confirmed that subsidies play an important role
in thinning operations. If subsidies would be
reduced due to the limited budget of Japanese
government, regeneration and procurement costs
should be reduced by developing new harvesting
systems and by enhancing the forest road
network in order to ease the extraction of timber
and forest biomass resources.
According to the increment of log price, the
annual available amounts of forest biomass
resources from profitable sub-compartments
were increased because the profitable sub-
compartments were increased (Table 4).
However, no broad-leaved forests were still
harvested in this scenario. Then, the forest biomass
resources prices were increased (Table 5).
As a result, the annual available amounts
of broadleaved trees from profitable
sub compartments were increased in direct
relation to increment of forest biomass resources
price.
3.3.	GHC Emissions
Tire GHG emission of the direct combustion
power generation facilities with a capacity of 5
MW was of 68 gCO2eq/kWh. On the other hand,
the GHG emission of a small-scale gasification
power plant with a capacity of 2.4 MW was 52
gCO2eq/kWh (Figure 4).
These values were higher than the CO2 emission
namely 46 gCO2/kWh for the direct combustion
and 41 gCO2/kWh for a small-scale gasification.
Komata et al. (2017) estimated the GHG emissions
to be about 80 gCO2eq/kWh for direct combustion
power generation facilities having a capacity
of 5.7 MW. Ministry of Environment (2013)
estimated GHG emissions as 195 gCO2eq/kWh
for a small-scale gasification facility.
The results of Komata et al. (2017) were similar
to those from this study. Ministry of Environment
Table 4
Availability of forest biomass resources and timber and the procurement costs with subsidy and
regeneration according to different log prices and for 3,000 JPY/tDM forest biomass resources prices
Source	8,000 JPY/m3	10,000 JPY/m3	12,000 JPY/m3
Total	9,033 tDM/year 5,960 JPY/tDM	12,044 tDM/year 6,571 JPY/tDM	15,054 tDM/year 6,501 JPY/tDM
Logging residues	2,358 tDM/year 7,875 JPY/tDM	3,999 tDM/year 8,010 JPY/tDM	4,780 tDM/year 8,124 JPY/tDM
Thinned Trees	6,675 tDM/year 5,284 JPY/tDM	8,045 tDM/year 5,856 JPY/tDM	10,274 tDM/year 5,745 JPY/tDM
Broadleaved Trees	0 tDM/year — JPY/tDM	0 tDM/year — JPY/tDM	0 tDM/year — JPY/tDM
Timber	33,595 m3/year 4,707 JPY/m3	57,003 m3/year 5,116 JPY/m3	68,162 m3/year 5,426 JPY/m3
Availability of forest biomass	Table 5 resources and timber, and procurement costs with subsidy and regeneration		
according to 10,000 JPY/m3log prices and different forest biomass resources prices			
Source	3,000 JPY/tDM	6,000 JPY/tDM	10,000 JPY/tDM
Total	12,043 tDM/year 6,571 JPY/tDM	27,096 tDM/year 8,713 JPY/tDM	30,108 tDM/year 9,040 JPY/tDM
Logging residues	3,999 tDM/year 8,010 JPY/tDM	4,862 tDM/year 8,652 JPY/tDM	5,007 tDM/year 8,689 JPY/tDM
Thinned Trees	8,045 tDM/year 5,856 JPY/tDM	13,749 tDM/year 6,444 JPY/tDM	15,023 tDM/year 6,348 JPY/tDM
Broadleaved Trees	0 tDM/year — JPY/tDM	8,485 tDM/year 12,425 JPY/tDM	10,077 tDM/year 13,228 JPY/tDM
Timber	57,003 m3/year	69,495 m3/year	71,577 m3/year
	5,116 JPY/m3	5,142 JPY/m3	5,143 JPY/m3
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
11
140
^^"GHG: direct combustion
generation capacity (kW)
Fig. 4. GHG and CO2 emissions related to the production capacity
(2013)	estimated the GHG emissions from more
detailed processes compared to the approach of
Yoshioka et al. (2005b) and Aruga et al. (2011)
whose methods were used in this study.
4.	Conclusions
This study estimated the annually available
amount of forest biomass resources from
profitable sub-compartments in Kanuma Area
of Tochigi Prefecture, Japan. It included the
regeneration expenses as a prerequisite of the
forest management sustainability as well as
discounting the future revenues and costs to the
present net values. In addition to the economic
balances, this study estimated the GHG emissions
including CO2, CH, and N2O. Under the FIT
program, the economic balances of both, direct
combustion and small-scale gasification, would be
positive if the steam could be sold to households.
However, it is difficult to use the steam
generated from power production plants in Japan
because the infrastructure for a district heating
system has not been established yet. Therefore,
power plants should be constructed on the saw
mills or near those factories that use the heat.
For log prices of 10,000 JPY/m3 and forest
biomass resources prices of 3,000 JPY/tDM,
the annual available amount of forest biomass
resources with subsidy and regeneration costs
was estimated at 12,043 tDM/year. Since subsidies
play important roles on economic balances of
regeneration and thinning operations in Japan,
the annual available amount of forest biomass
resources without subsidies was reduced to 2,710
tDM/year. However, subsidies would be reduced
due to the limited budget of Japanese government.
Therefore, low-cost forest operations should
be developed by increasing the mechanization
level and by developing further the forest road
networks.
Tire GHG emissions of the direct combustion
facilities having a capacity of 5 MW was of 68
gCO2eq/kWh. On the other hand, the GHG
emission of a small-scale gasification power plant
having a capacity of 2.4 MW was of 52 gCO.eq/
kWh.
Tire result was similar to that of Komata
et al. (2017), but not to that of Ministry of
Environment (2013) because the later estimated
the GHG emissions from more detailed processes
compared to Yoshioka et al. (2005b) and Aruga
et al. (2011) whose methods were used in this
study. Therefore, more detailed analyses should
be conducted by implementing future studies.
Acknowledgements
This study was supported by JSPS KAKENHI grant
number 15H04508 and 16KK0168.
12
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
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Forestry. Fiscal Year 2011 (summary), Forestry Agency
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Kazuhiro ARUGA
Associate Professor, Department of Forest Science, Faculty of Agriculture,
Utsunomiya University, 350 Mine, Utsunomiya 321-8505, Japan.
Tel. +81-28-649-5537, Fax. +81-28-649-5545, aruga@cc.utsunomiya-u.ac.jp
Economic Balances and GHG Emissions of Forest Biomass Utilization
in Kanuma Area of Tochigi Prefecture, Japan
Abstract
This study estimated the annual available amount of forest biomass resources from profitable sub-compartments
in the Kanuma Area of Tochigi Prefecture, Japan, by considering the regeneration expenses incurred by the
sustainability of forest management and by discounting the future revenues and costs to the present net values.
In addition to the economic balances, this study estimated the GHG emissions including CO„ CH4, and N,O.
Under the Feed-in-Tariff program, the economic balances of both, direct combustion and small-scale gasification
facilities would be positive. For log prices of 10,000 JPY/m3 and forest biomass resources prices of 3,000 JPY/tDM,
the annual available amount of forest biomass resources with subsidies and regeneration costs was estimated
at 12,044 tDM/year. Since subsidies play important roles on economic balances of regeneration and thinning
operations in Japan, the annual available amount of forest biomass resources without subsidies was reduced to
2,710 tDM/year. In relation to log price increments, the annual available amounts of forest biomass resources
were increased. The GHG emission of the direct combustion plants having a capacity of 5 MW was of 68 gCO,eq/
kWh. On the other hand, the GHG emission of a small-scale gasification power plants having a capacity of 2.4
MW was 52 gCO.,eq/kWh. Further studies should be undertaken for detailed analyses.
Keywords: available amount, economic balance, forest biomass resource, GHG emission, supply
potențial
Balanța economică și emisiile de gaze cu efect de seră relaționale cu utilizarea
biomasei forestiere în zona Kanuma, Tochigi, Japonia
Rezumat
Prezentul studiu estimează cantitatea de biomasă forestieră disponibilă anual în unități amenajistice
considerate a fi profitabile, localizate în zona Kanuma, Tochigi, Japonia prin luarea în considerare a cheltuielilor
de regenerare cauzate de menținerea sustenabilității managementului forestier și prin raportarea veniturilor și
costurilor previzionale la valoarea actuală netă. Pe lângă balanțele economice, studiul estimează emisiile de gaze
cu efect de seră incluzând aici emisiile de CO„ CH4, și N,O. Sub programul de tarifare a energiei, atât balanța
economică a facilităților de combustie directă cât și cea a facilităților de producție a gazului la scară mică ar fi
pozitive. Pentru prețuri ale masei lemnoase sub formă de buștean de 10.000 yeni/m3 și prețuri ale resurselor
forestiere de biomasă de 3.000 yeni/tonă masă uscată, cantitatea de biomasă forestieră disponibilă anual în
scenariul includerii subvențiilor și a costurilor de regenerare a fost estimată la 12.044 tone masă uscată/an. Din
moment ce subvențiile joacă roluri importante în balanța economică a lucrărilor de regenerare și a aplicării
răriturilor în Japonia, cantitatea de biomasă forestieră disponibilă anual în scenariul excluderii subvențiilor a fost
redusă la 2.710 tone masă uscată/an. în relație directă cu creșterea prețului masei lemnoase a fost și cantitatea
de biomasă forestieră disponibilă anual. Emisiile de gaze cu efect de seră specifice facilităților de combustie
directă caracterizate de o capacitate de 5 MW a fost de 68 gCO,eq/kWh pe când, emisiile de gaze cu efect de
seră specifice unor facilități de producție a gazului la scară mică caracterizate de capacități de 2,4 MW au fost
de ordinul a 52 gCO,eq/kWh. Necesitatea unor analize de detaliu trebuie adresată prin realizarea de noi studii.
Cuvinte cheie: cantitate disponibilă, balanță economică, resursă forestieră de biomasă, emisii de gaze
cu efect de seră, potențial de aprovizionare
14
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
Using Sound Pressure Sensors
to Monitor the Performance of
Manually Operated Circular Saws:
What Parameters and to What
Extent Can They Be Inferred?
Marius CHEȚA
Daniel ȘERBAN
Gheorghe IGNEA
Rudolf Alexandru DERCZENI
Victor SFECLĂ
Stelian Alexandru BORZ
1.	Introduction
Delivery of various wood products to final
consumers spans a wide supply chain composed of
operațional processes developed in the forest, on
the transportation infrastructure, in the primary
timber processing facilities (Oprea, 2008) and in
the final wood product development facilities.
Timber harvesting and its subsequent industrial
processing contributes to a significant extent to
the Romanian GDP (Gligoraș and Borz, 2015) and
it has a lot of potențial in the creation of jobs.
Timber harvesting operations in Romania
are characterized by the use of rather low-level
mechanization systems usually making use of
motor-manual tree felling and processing, horse
logging and cable skidding (Borz and Ciobanu,
2013; Borz et al., 2013; Borz et al., 2015). At the
same time, it is reasonable to assume that it is also
the case of primary wood processing facilities as
most of them are configured and are working
as small-medium scale businesses. For instance,
there were more than 7000 primary wood
processing facilities in Romania as of 2007 (Sbera,
2007) with wood processing capacities ranging
from 8-10 to thousands of m3 per day.
Most of the product-oriented Industries use to
some extent equipment and tools that are designed
to fulfill their production needs. To cope with
market requirements and customer satisfaction,
production managers are concerned with their
product development processes, Insurance of
production quality and timing of their product
release on the market. Similar to small-scale
harvesting operations (Talagai et al., 2017; Spinelli
et al., 2012), small-scale entrepreneurs working
into wood processing industry do not have the
necessary resources to acquire large-scale fully
automated equipment which is far too expensive
for their economic context and market segment.
At the same time, it is rather difficult for them to
cooperate in order to develop large-scale business
and wood processing applications since they are
competitors within the frame of wood processing
industry and on the processed wood products
market. Therefore, they are using affordable tools
and equipment and are struggling to save money
in order to remain competitive.
Meanwhile, one of the current problems of
the Romanian wood related industry is that
related to the training level of the personnel
(Rauch et al., 2015). This situation may come as
a result of limited financial resources to keep
on-the-job highly-trained professionals in the
industry as well as an effect of a lack of dedicated
training programs. On the other hand, by their
competences and expertise, such professionals
may contribute significantly to the increment
of the operațional efficiency including here an
improved operation of the tools and of the time
management in their jobs.
Wood sawing mills use different equipment
configurations to convert the logs into sawn timber
and other primary processed wood products
depending on their marketed products. The main
equipment is that converting the logs into lumber
or other primary products. Among the existing
options for such operations are the bând saws
(Gligoraș and Borz, 2015; Istvanic et al., 2009).
Then, depending on the processing level as well as
on the manufactured products, some of the wood
processing facilities use equipment for trimming
operations. Such equipment is used to make
transversal cuts and helps in obtaining shorter
wood pieces which are further integrated into
different wood-based products. Most commonly,
the equipment used in the wood processing facilities
is powered by electricity which comes from the
național grid, while the maintenance tools (i.e. blade
sharpening equipment) use the same energy inputs.
Since in such production facilities work, more or
less simultaneously, several equipment and tools,
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
15
a general system optimization should aim, among
other things, to enhance the electrica! energy
savings, resulting also in lower product releasing
costs, that could be attained by an adequate work
organization, especially by removing delays and by
increasing the utilization level of machines. To this
end, forest production studies represent a valuable
tool in the overall system’s optimization as they can
be used to experiment, observe, model and compare
options (Spinelli and Magagnotti, 2012). Such studies
may include the measurement of energy inputs
required by the product development. For such
attempts, studies can be implemented at different
resolutions (Spinelli and Magagnotti, 2012) and the
use of modern approaches such as those making
use of sensors have a lot of potențial in reducing the
resources required by their implementation (Borz,
2016; Talagai and Borz, 2016).
The goal of this study was to test to what extent
the sensors used to measure the sound pressure
level can be used to monitor and collect data for
manually operated wood trimming equipment.
2.	Materials and Methods
2.1.	Study Location, Equipment Description and
Data Collection Procedures
This study was carried out in a wood processing
facility located in Brașov, Romania which wished
to remain anonymous.
They use primary processed wood to develop
a series of wood products from resinous lumber.
In particular, they are manufacturing wood boxes
Fig.l. Storage boxes - a typical product of the
studied wood processing facility
(Figure 1) which are sold to various customers
that use them to store other products. Most of
the product design involves the use of otherwise
short wood pieces, produced from regular lumber,
that are part of the final assemblies.
Therefore, an important part of the operations
carried on in the wood processing facility are
shaped around trimming operations of the
lumber which are carried on using a manually
driven circular saw (Figure 2). As mentioned,
in such operations, energy inputs come from
the național electricity grid. At the same time,
in small wood processing facilities, energy
Fig.2. Description of the studied circular saw and of the used datalogger. Legend: right: 1 - main Steel spar,
2 - blade protection, 3 - starting/stopping control, 4 - retracting mechanism, 5 - engine, 6 - blade, 7 - sawing
Table, 8 - Steel frame; left: 1 - protected microphone, 2 - case of the datalogger, 3 - USB port
16
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
savings are particularly important in order to
maintain the wood processing costs as low as
possible. This comes forth also as a result of
quite expensive raw woody material as being
characteristic lately in Romania. Therefore, the
equipment running time should be planned based
on the production requirements and it should
be kept to the minimum required to process the
wood. Nevertheless, the equipment such as that
taken into study has no monitoring capabilities
due to the low technological integration. It is
constructed to align the power saw capabilities
with that of manual handling of the wood pieces
to be trimmed and the switch-off functions are
manually controlled rather than in an automatic
way, while the running time depends greatly
on the operațional behavior of the workers.
Therefore, the effective trimming time always
overlaps with the engine running time but it is
reasonable to assume that the two are never the
same.
The circular saw taken into study (Figure 2) was
built by the wood processing facility’s employees
and it is powered by a 1.75 kW electrical engine
being equipped with a circular blade of 400 mm
and having a number of 99 sawing teeth. The
saw ensures a cutting height of 110 mm and a
transversal movement across the sawing table
of 700 mm. The equipment is manually driven
during the active sawing time and it retracts
mechanically following such actions.
To monitor the behavior of the studied
equipment we used a sound pressure level
datalogger (Figure 1) developed and produced by
Extech ®, able to collect data at high sampling
rates and to export it in native format of the
producer as well as MS Excel ® spreadsheets.
It enables the setup of various sampling rates
starting from 50 milliseconds for a computer-
based data capture setup, respectively half of a
second for externally conducted applications. The
device configuration is done using the dedicated
software that enables the choice of specific
sampling parameters including the sampling rate.
For this study, we have setup and used
sampling parameters such as the minimum
available sampling rate for externai applications
(500 milliseconds), slow recording mode and the
dB(A) scale. These settings were done in the office
phase of the study following that the datalogger
start to be made manually after its placement
on the studied trimming equipment. Then, the
datalogger was placed on the equipment in a place
that avoided any interference with the usual way
of doing the trimming work, near the electrical
engine and the trimming blade (Figure 2).
To observe the real events during the operations
we have used the video-camera of a smartphone
that was setup to record files in real time. It was
placed at approximately 2 meters away of the saw
as specified in Figure 3.
Then the datalogger was manually set to collect
Fig.3. Video camera setup
Revista pădurilor • Anul 132 • 2017 • Nr. 1
17
data and the real operations were recorded by
both devices for a usual working day.
2.2.	Data Processing and Analysis
Data captured by both devices was downloaded
into a computer using different approaches. Video
data was transferred from the internai memory
of the video-camera using regular procedures
and it was stored in a folder containing the
video collected files in their natural succession.
dhen the data stored on internai memory of the
datalogger was downloaded via its dedicated
software (Figure 4).
While on a first glance such software may help
operațional regimes the data was exported into
MS Excel ® sheets, a function that is enabled by
the datalogger’s software.
The exported data comes with date and time
stamps for each observation taken at the selected
sampling rate, a feature that helps in further
assessments that use the time as a variable.
To pair the Information from video-collected
data with that from the used sensor, a tradițional
approach of using freely available video software
was not feasible given the sampling rate of
the sensor. Therefore, this study used freely-
available video-editing software to broke the
files into frames captured at 500 milliseconds.
the researchers to distinguish between certain
patterns and to see the behavior of the studied
equipment in terms of sound pressure level it does
not allow any kind of data segmentation based,
for instance, on specified thresholds. However,
one can easily see three distinct patterns within
the data pool as being specific to the studied
working regimes.
In order to be able to separate the specific
Then, we have synchronized the video files and
frames with the data collected by the sensor.
Afterwards, a MS Excel ® database has been built
to contain the Information coming from the two
approaches. To this end, each of the produced
and synchronized frames was carefully analyzed
to deduct the operațional behavior of the studied
equipment. This approach was particularly
useful for those time segments characterizing the
18
Revisla pădurilor • Anul 132 • 2017 • Nr. 1
effective sawing (S) time as well as the retraction
(R) time that were grouped into the operating (O)
time. At the same time, the running time without
effective sawing (RUN) as well as down time
(STOP) were observed on the images. For each of
the 500-millisecond extracted frame, data coming
from the sensor was paired with codes following
the image analysis. The resulted database was used
further for analysis that assumed computations
and time separation based on user-defined
thresholds. After a careful analysis of the data, a
threshold value was taken into consideration to
separate the running and downtime regimes. It
was set to 86.5 dB(A). Obviously, this was specific
to the experimental design that was used in this
study, knowing that the sound pressure level may
be affected by sound attenuation as a function of
the distance from the emitting source as well as
by sound reflection due to indoor measurements
which adds to the regular sound pressure level.
Nevertheless, in other kind of setups one can
infer such a threshold based on the data plotted
by the sensor’s software or that plotted against
time using externai software such as MS Excel
®. On the other hand, in studies such as that
described herein, it is rather unrecommended to
place sound pressure level sensors far away of
the emitting source as sound or noise produced
by other equipment or activities may interfere
with that of the studied one. Tire effective sawing
and retracting regimes were rather difficult
to separate. This can be related to the size of
trimmed wood pieces as the time needed and the
emitted noise depend on such characteristics.
Figure 4 shows such a behavior in the first part of
the data pool collected by the sensor. Therefore,
it was typically to obtain a pattern specific to
certain dimensions of the trimmed wood pieces
but as their size decreased, lower sound pressure
level peaks appeared in the plotted data pool. To
this end, we assumed a low recognition ability for
the number of undertaken trims and we used a
threshold able to detect only the trims made on
larger wood pieces. It was setup at 110 dB(A) that
enabled the detection of a single value for each
of the trimmed pieces resulting this way into
a counter. Due to the same reasons, we did not
attempt to separate the effective sawing time by
a threshold-based extraction from the data pool
as the size of the trimmed wood pieces and the
sampling rate did not allow for such an endeavor.
For demonstration purposes, we have selected
a time interval of 10 minutes where we found
the greatest variability of the studied parameters
and we ran the analysis using the mentioned
thresholds on that part of the data pool.
3.	Results and Discussion
Our results indicate that the approach used in
this study has a lot of potențial in the attempt to
monitor the operațional behavior including here
the performance of the small tools and equipment
used in primary wood processing facilities.
One of the key issues here is that related to the
running vs. downtime because, if no trimming
operations are actually carried out then keeping
the engine running is counterproductive from
the energy saving point of view. To this end,
the threshold set for the sound pressure level
corresponding to the two behavioral States (down
vs. running) succeeded to separate the time spent
into the two with a recognition accuracy of
almost 100%.
As a fact, when comparing the running time
as extracted from the sensor-collected data with
that captured by the video-surveillance approach
we have obtained a difference of -0.24% (Table
1). Tire same applied to the extraction of down
time where the difference was of +0.54%. Most
probably, these small differences are the effect
of a rapid transition of the sound pressure level
when switching between the two States (Figure
5) that could not be observed using the sampling
rate described herein.
Conventionally (Figure 5), the running
behavior was plotted as 85 dB(A) for the “ON”
state and as 80 dB(A) for the “OFF” state.
In what concerns the automatic recognition of
the number of trimmed wood pieces, the things
were different. Here, the threshold set for the
extraction of those events failed to give accurate
results. This was an effect of scale as mentioned
before as the obtained recognition accuracy of
the used threshold was of only 66.67% resulting
into a large difference (-33.33%) compared to the
video-surveillance approach (Table 1).
To this end, by using the same type of sensor,
one may take a look into the data plotted against
time to observe the number of wood pieces that
were processed. Another approach is that of
linking the sensor to a computer by an externai
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
19
Table 1
Comparison ov video-extracted and sensor collected data
Parameter	Extracted from video files	Extracted from sound pressure level data	Recognition accuracy [%]
Trimmed pieces	30	20	- 33.33
Running time - RUN (s)	414.5	413.5	-00.24
Down time - STOP (s)	186.0	187.0	+00.54
cable to take measurements to a higher sampling
rate that could solve this inconvenient by
sampling the data in real-time and storing it on a
computer drive.
Nevertheless, the energy inputs in such
operations depend on that time in which the
equipment runs instead of that in which the
equipment is actually used to process the wood.
From this point of view, the obtained results were
consistent and the approach could be used to
monitor in an effective way such operations to
take measures for improvement.
driven sawing equipment. Tire results were
rather encouraging because such an approach
can accurately separate the two most important
operațional regimes related to the energy saving.
It is possible to get more accurate results by
adjusting the sample rate to a higher one, an option
that should be explored further. Nevertheless, a
full automation of data collection and analysis is
still not achievable as some “eye observation” and
“human intelligence” by supervised training of
the used thresholds and algorithms is still needed
to be able to accurately separate the regimes. This
is the effect of the size of processed lumber as well
as of the sensor placement. On the other hand,
Fig.5. Separation of operațional regimes of the studied equipment using thresolds. Legend: dotted black line
- sound pressure level dB(A) as downloaded from the datalogger, continuous green line - running regime;
continuous red line - stopped regime, continuous blue line - number of recognized cuts
4.	Conclusions
This study aimed to test to what extent the
sound pressure level sensors may be used to
monitor and collect data for small-scale manually
such supplementary actions are needed to a less
extent compared with what could be achieved
following the setup of adequate thresholds.
20
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
Acknowle dgements
The authors of this paper would like to thank to the
Department of Forest Engineering, Forest Management
Planning and Terrestrial Measurements of the Faculty
of Silviculture and Forest Engineering, Transilvania
University of Brașov, for the logistics and support in
carrying out this study. This study is a synthesis of the
References
Borz, S.A., C i o b a n u, V.D., 2013: Ejficiency cf
motor-manual felling and horse logging in small-scale
firewood production. African Journal of Agricultural
Research, 8 (24), pp. 3126-3135.
B o r z, S. A., D i n u 1 i c ă, F., B î r d a, M.,
I g n e a, G., C i o b a n u, V.D., Popa, B., 2013: Time
consumption and productivity cf skidding Silver fir
(Abies alba Mill.) round wood in reduced accessibility
conditions: A case study in windthrow salvage logging
form Romanian Carpathians. Annals of Forest
Research, 56 (2), pp. 363- 375.
Bor z, S. A.,Ign ea, G.,P opa, B., Spâr che z, G.,
I o r d a c h e, E., 2015: Estimating time consumption and
productivity cf roundwood skidding in group shelterwood
system - a case study in a broadleaved mixed stand located
in reduced accessibility conditions. Croatian Journal of
Forest Engineering, 36 (1), pp. 137-146.
B o r z, S. A., 2016: Tuming a winch skidder into a
sef-data collection machine using externai sensors: a
methodological concept. Bulletin of the Transilvania
University of Brașov, Series II, 9 (58) 2, pp. 1-6.
G1 i g o r a ș, D., B o r z, S. A., 2015: Factors ajfecting
the eJfective time consumption, wood recovery andfeeding
speed when manufacturing lumber using a FBO-02 cut
mobile bandsaw. Wood Research 60 (2), pp. 329-338.
I s t v a n i c, J., L u c i c, R. B., J u g, M., K a r a n, R.,
2009: Analysis cffactors ajfecting log bând saw capacity.
Croatian Journal of Forest Engineering 30 (1), pp. 27-35.
MSc thesis of Mr. Eng. Daniel Șerban that has been
defended in the Department of Forest Engineering,
Forest Management Planning and Terrestrial
Measurements - Study Program Management and
Technical Systems in Forest Engineering. The authors
acknowledge the support of the wood processing
facility in carrying out this study.
M a g a g n o 11 i, N., S p i n e 11 i, R., Eds., 2012: COST
Action FP0902 - Good practice guideline for biomass
production studies. CNR IVALSA, Florence, Italy, ISBN
978-88-901660-4-4, 41 p.
Oprea,!., 2008: Timber harvesting technology [in
Romanian], Transilvania University Press, Brașov.
R	a u c h,	P., W o 1 f s	m a y r, U. J., B o r z, S.	A,
T r	i p 1 a	t, M., K r a j n c N., K 1 o c k,	M.,
O b	e r w	i m m e r,	R, K e t i k i d i s,	C.,
V a s i i e v i	c, A., S t a u	d e r, M., M ii h 1 b e r g,	C.,
Dercz eni, R.A., O r a v e c, M., K r i s s a k o v a, L,
H a n d 1 o s, M., 2015: SWOT analysis and strategy
development cf forest fuel supply chains in South East
Europe. Forest Policy and Economics 61, pp. 87-94.
S b e r a, L, 2007: Wood resources and the market
potențial in Romania [in Romanian]. Meridiane
Forestiere 2, pp. 3-7.
S p i n n e 11 i, R., S c h w e i e r, J., de Francesco, F.,
2012: Harvesting techniques for nonindustrial biomass-
plantations. Biosystems Engineering 113 (4), pp.
319-324.
T a 1 a g a i, N, B o r z S. A, 2016: Concepts for
data collection automation with applicability in the
operațional petformance assessment cf willow short
rotation crops [in Romanian]. In: Revista Pădurilor, voi.
131 (3/4), pp. 74-90.
T a 1 a g a i, N, B o r z, S. A, I g n e a, G., 2017:
Peiformance cf brush cutters in felling operations cf
willow short rotation coppice. BioResources, 12 (2), pp.
3560-3569.
Eng. Marius CHEȚA
Department of Forest Engineering, Forest Management Planning and Terrestrial Measurements, Faculty of
Silviculture and Forest Engineering, Transilvania University of Brașov, Șirul Beethoven No.l, 500123, Brașov,
Romania
e-mail: marius.cheta@unitbv.ro
Eng. Daniel ȘERBAN
Department of Forest Engineering, Forest Management Planning and Terrestrial Measurements, Faculty of
Silviculture and Forest Engineering, Transilvania University of Brașov, Șirul Beethoven No.l, 500123, Brașov,
Romania
e-mail: dannys_92@yahoo.com
Prof.dr.eng. Gheorghe IGNEA
Department of Forest Engineering, Forest Management Planning and Terrestrial Measurements, Faculty of
Silviculture and Forest Engineering, Transilvania University of Brașov, Șirul Beethoven No.l, 500123, Brașov,
Romania
e-mail: igneagh@unitbv.ro
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
21
Assoc.prof.dr.eng. Rudolf Alexandru DERCZENI
Department of Forest Engineering, Forest Management Planning and Terrestrial Measurements, Faculty of
Silviculture and Forest Engineering, Transilvania University of Brașov, Șirul Beethoven No.l, 500123, Brașov,
Romania
e-mail: derczeni@unitbv.ro
Assist.prof.eng. Victor SFECLĂ
Department of Forestry and Public Gardens, Faculty of Horticulture, State Agrarian University of Moldova,
Mircești, 44, Chișinău, MD-2049
e-mail: v.sfecla@uasm.md
Prof.dr.eng. Stelian Alexandru BORZ
Department of Forest Engineering, Forest Management Planning and Terrestrial Measurements, Faculty of
Silviculture and Forest Engineering, Transilvania University of Brașov, Șirul Beethoven No.l, 500123, Brașov,
Romania
e-mail: stelian.borz@unitbv.ro
Using Sound Pressure Sensors to Monitor the Performance of Manually Operated Circular Saws:
What Parameters and to What Extent Can They Be Inferred?
Abstract
Operațional performance and energy inputs are key issues when designing and implementing product-
oriented systems because such systems make use of tools and equipment to deliver their products. In small-
scale wood processing facilities energy savings and an improved time management are crucial in order to stay
competitive. This often results in the necessity to reconfigure operațional processes or to train the personnel to
improve its skills, but in order to do that, it is required to monitor how the operations are implemented. This
study tests the possibility to use sound pressure level sensors to monitor the operațional behavior of manually-
operated circular saws in wood trimming operations. Following a comparative design, the results indicate a
good potențial to use a threshold-setting approach in monitoring the equipment, as the separation between the
running and down time was possible and accurate. Nevertheless, the extraction of effective sawing time as well
as of the number of trimmed wood pieces that indicate the production, was rather difficult and inaccurate for the
time being but it would be possible to infer such parameters by using higher sampling rates.
Keywords: wood processing, monitoring, energy saving, sound pressure level, sensor, automation
Utilizarea senzorilor de măsurare a nivelului de presiune acustică la monitorizarea
performanțelor ferăstraielor circulare acționate manual: ce parametri pot fi estimați și în ce măsură
pot fi aceștia estimați?
Rezumat
Performanța operațională și consumul de energie reprezintă aspecte cheie în dezvoltarea și implementarea
sistemelor orientate pe generarea de produse deoarece astfel de sisteme utilizează unelte și echipamente în
manufacturarea de produse. în facilitățile de prelucrare primară a lemnului, economisirea energiei și un
management îmbunătățit al timpului sunt cruciale pentru asigurarea competitivității, fapt ce conduce la
necesitatea reconfigurării proceselor operaționale și la training pentru îmbunătățirea competențelor muncitorilor.
Pentru a fi realizabile cele menționate, este necesară monitorizarea modului de implementare a operațiilor. Acest
studiu testează posibilitatea de a utiliza senzori de măsurare a nivelului de presiune acustică pentru a monitoriza
comportamentul operațional al ferăstraielor circulare acționate manual. Rezultatele studiului indică că, prin
utilizarea unor valori prag, separarea timpului de funcționare în diferite regimuri este posibilă și suficient de
precisă. Cu toate acestea, extragerea timpului consumat efectiv cu tăierea precum și a numărului de tăieturi
au fost mai greu de realizat iar rezultatele obținute au fost mai puțin precise. Totuși, utilizarea unor rate de
eșantionare mai mari ar putea să îmbunătățească aceste rezultate.
Cuvinte cheie: prelucrarea lemnului, monitorizare, economisirea energiei, nivel de presiune acustică,
senzor, automatizare
22
Revisia iadurilor • Anul 132 • 2017 • Nr. 1
Irish Wood Fuel DataBase - A WEB
Based DataBase of Wood Fuel
Parmeters
Enda COATES
Brian CRONIN
Christopher MCGURREN
Nicholas MOCKLER
Eleanor OWENS
Maeve KENNEALY
Tom KENT
1.	Introduction
Ireland is required to produce 16% of its energy
from renewable sources by the year 2020 (***,
2010). Wood fuel is the second largest source of
renewable energy in Ireland after wind (Coford,
2014). It is estimated that due to EU directives,
the demand for forest based biomass for energy
in Ireland will be 3,084,000 m3 per annum by the
year 2020 (***, 2011). However, it is estimated
that only 1,453,000 m3 of forest biomass will be
available for the bio energy market from currently
employed supply chains (Phillips, 2011). This
forecast of supply only estimates stern wood,
and does not take into account the biomass that
may be mobilized from branches and tree tops.
There is a relatively new category that has been
introduced by the Department of Agriculture’s
afforestation scheme to support the planting
of new species of trees to help bridge this gap.
This new category, Forestry for Fibre, aims to
introduce fast growing species such as poplar,
eucalyptus, and alder specifically for fibre to be
used in wood fuel supply chains and to also feed
panel board mills. As these biomass streams from
forest residues and new species develop, data
on the wood fuel parameters of the materials
is needed, in order for biomass users to decide
if the material is suitable in their combustion
systems. In an effort to inform the industry on the
makeup of these biomass feedstocks, the database
described in this study has been created.
2.	Materials and Methods
2.1.	Field Sampling
A number of specimen trees of each genus
were felled by chainsaw: alder (Alnus glutinosa),
ash (Fraxinus excelsior L.), birch (Betula pendula
& B. pubescens), lodgepole pine (Pinus contorta
Dougl.\ Norway spruce (Picea abies (L.)
Karst.), Sitka spruce (Picea sitchensis (Bong.)
Carr.), hybrid poplars (Populus sp.), Eucalyptus
delegatensis, and Eucalyptus nitens.
Each tree was cross cut at the height where
the stern measured 7 cm in diameter, and the
top was removed and weighed. Tire branches
along the stern were removed and separated into
live and dead branches and each partition was
weighed. Three branches from each category,
(a large, medium, and small branch) were then
Fig. 1. Collection of stern discs from a
Eucalyptus delegatensis specimen
selected as representative samples and bagged.
Tire remaining live and dead branches, and the
tree top, were then chipped separately with a
TP200 chipper, and three woodchip samples
(each approx. 1000 g) were collected, bagged, and
weighed. Diameter measurements were taken at
1 m intervals along the stern. Discs of 25 - 30 mm
thickness were cut by chainsaw approx. every
3 m along the stern. These disks were weighed
and bagged for analysis (Figure 1). The analysis
procedures are described below.
2.2.	Determination cfMoisture Content
Sample moisture content was determined
on three replicates using the oven dry method
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
23
at 105 °C for 48 hours, according to EN 14774-
3 (***, 2009a), and expressed as a percentage of
total weight. Moisture content, expressed as
a percentage of total weight, was calculated
according to Equation 1.
Moisture content % =	x 100
\ /
where: W is the wet mass, in grams, of the
sample, D^is the dry mass in grams, of the sample.
2.3.	Determination of Basic Density
Basic density was estimated using the stern
disks sampled in the field. The samples were
placed under water for 24 hours in order to
become fully saturated. A bucket of water was
placed on a mass balance and a weight reading
was recorded. The saturated discs were then
submerged below the water level in the bucket
using teasing needles to hold the disc in place
just below the surface. Then a new reading on the
mass balance was taken again.
The difference between the reading before
submersion and during submersion was converted
from weight to volume.
2.4.	Preparation of Sampled Material
Prior to the determination of ash content,
calorific value, and Chemical contents, the samples
were comminuted to a partide size of less than 1
mm. Each sample was dried in an oven, and then
comminuted using a Fritsch Universal Cutting
Mill Pulverisette 19. Stern discs and some branch
material which were too large to comminute in
the cutting mill were fir st reduced in partide size
by splitting and chipping.
2.5.	Determination of Ash Content
Ash content was determined according to
EN 14775:2009. Briefly, approximately 1 g of the
comminuted sample was weighed in a porcelain
dish and burned to a temperature of 550 ± 10 °C
using a Mason Technology Nabertherm muffle
furnace. Tire sample analyses were replicated three
times and the results were expressed on a dry basis
according to EN 14775 (***, 2009b) (Equation 2).
—--------------1 X 100 X --------- (2)
7n2_wi1	\100-MaciJ I ' '
where: m^ is the mass, in grams, of the empty
dish, m2 is the mass, in grams, of the dish plus the
test sample, m3 is the mass, in grams, of the dish
plus ash and Mad is the % of moisture content of
the test sample used for the determination.
2.6.	Determination of Gross Calorific Value
(GCV)
Gross Calorific Value (GCV) at constant
volume was determined according to EN 14918
(***, 2009c). Briefly, 1 g of sample was combusted
using a Parr 6300 automated isoperibol bomb
calorimeter calibrated with benzoic acid. AII
sample analyses were replicated three times and
were expressed on a dry basis according to EN
14918 (***, 2009c) (using Equation 3).
Qv.gr * 100-Mad
where: qv rd is the gross calorific value at
constant volume of the dry (moisture free) fuel,
in megajoules per kilogram, Mad is the moisture
content in the analysis sample, in percentage
by total mass, is the gross calorific value at
constant volume of the fuel as analyzed, in joules
per gram.
2.7.	Determination of Carbon, Hydrogen, Nitrogen,
Chlorine and Sulphur Contents
Samples were sent to the Microanalytical lab of
the University College Dublin, Ireland for CHN, CI
and S analysis. CHN and S were measured using
an Exeter Analytical CE 440 elemental analyzer. CI
was determined through a titrimetric method.
2.8.	Determination of Metal Content
The samples were analyzed for minor elements
arsenic (As), cadmium (Cd), chromium (Cr), copper
(Cu), mercury (Hg), nickel (Ni), lead (Pb) and zinc
(Zn) and were prepared by using an adapted
method of EN 15297:2011. 400 - 500 mg of the
sample (< 1 mm nominal top size) was weighed
and mixed with 8 ml 69% Puriss HNO( and 2 ml
35% H,O„ Samples were digested in a closed
vessel using a CEM Marș 5 Station using a specific
temperature profile:
-	temperature increased to 190 °C over 15
minute s;
-	temperature was kept at 190 °C for 15 minutes;
-	samples were allowed to cool down for 20
minutes.
Samples were filtered using Whatman 42 70 mm
24
Revisla pădurilor • Anul 132 • 2017 • Nr. 1
filter paper and diluted up to 25 ml using 2% HNO3
and stored at 4° C in polypropylene sample bottles.
Metal analysis was carried out using a Variau 710-
ES Inductively Coupled Plasma Optical Emission
Spectrometer (ICP-OES).
Single element standards were prepared for
As, Cd, Cr, Cu, Pb, Hg, Ni and Zn using 2% EINO3.
Concentrations of the standards Solutions are
listed in Table 1. Wavelengths were chosen for
each element according to the following:
-	best interference free line;
settings are listed in Table 2.
2.10. Limit cf Detection and Limit cf
Quantification Determination
The limit of detection (LOD) and limit of
quantification (LOQ') for each element was
determined by analyzing ten blank Solutions using
the standards and wavelengths listed in Table 3.
LOD and LOQ values were determined using the
calculations below provided by the Variau ICP
instrument:
Table 1
Metal standard concentrations (mg/1) with selected wavelengths (nm)
Element	Wavelength Ă (nm)	Std 1	Std 2	Std 3	Std 4	Std 5	Std 6
As	188.980	0.1	1.0	10.0	___	—	—
Cd	226.502	0.0007	0.0015	0.004	0.007	0.01	___
Cr	267.716	0.001	0.005	0.01	0.025	0.04	___
Cu	327.395	0.005	0.1	0.2	0.3	0.4	___
Hg	253.652	0.1	1.0	10.0	___		___
Ni	231.604	0.004	0.02	0.04	0.05	___	___
Pb	220.353	0.1	1.0	10.0	___	___	___
Zn	213.857	0.01	0.05	0.1	1.0	2.0	3.0
-	greatest intensity with lowest background
noise and,
-	the best correlation coefficient (> 0.9950).
Determined sample values were the mean
metal content of three replicates (mg/kg) (db) ±
standard deviation which were calculated using
the Equation 4.
W = Ci^XV x ----------------—______	(4)
1 m (100-Mad)
where: w. was the concentration of the element in
the sample, on a dry basis, in mg/kg, c. was the
concentration of the element, in the diluted sample
digest, in mg/1, cio was the concentration of the
element, in the solution of the blank experiment, in
mg/1, Fwas the volume of the diluted sample digest
solution, in ml, m was the mass of the test portion
used, in g and M , was the moisture content in the
analysis test sample in % m/m.
2.9.	Instrumentation for Metal Content
A Variau 710-ES Inductively Coupled Plasma
Optical Emission Spectrometer (ICP-OES)
equipped with a SPS3 autosampler was used for
the analysis of the samples.
Instrumental conditions and sample introduction
LOD = (3 x the average of the standard
deviation results of 10 blank replicates);
LOQ = (10 x the average of the standard
deviation results of 10 blank replicates).
Table 2
Varian 710-ES operating parameters
Operating parameters	Value
Power (kW)	1.0
Plasma flow (L/min)	15.0
Auxiliary flow (L/min)	1.5
Nebulizer pressure (kPa)	200.0
Replicate read time (s)	5.0
Instrument Stabilization delay (s)	15.0
Sample introduction settings	
Sample uptake delay (s)	30.0
Pump rate (rpm)	15.0
Rinse time (s)	10.0
Fast pump (sample delay/rinse)	On
General settings	
Replicates	3.0
Correlation coefficient	>0.9950
2.11.	Certified Reference Material
Method accuracy was determined using a
certified reference material (CRM), Measured
metal content was compared to the certified
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
25
Table 3
LOD and LOQ determined for each element analyzed (mg/kg)
Element	Wavelength, X (nm)	LOD (mg/kg)	LOQ (mg/kg)
As	188.980	0.1297	0.4323
Cd	226.502	0.0018	0.0062
Cr	267.716	0.0034	0.0114
Cu	327.395	0.0040	0.0135
Hg	253.652	0.0019	0.0066
Ni	231.604	0.0043	0.0143
Pb	220.353	0.0370	0.1230
Zn	213.857	0.0019	0.0066
			Table 4
Details of the recovery of the elements from the certified reference material			
Element	CRM (mg/kg)	Obtained (mg/kg db)	% Recovery
As	0.112 ± 0.004	ND*	0
Cd	1.52 ± 0.04	1.18 ± 0.14	77.42
Cr	1.99 ± 0.06	2.11 ± 0.05	106
Cu	4.7 ± 0.14	3.66 ± 0.13	77.88
Hg	0.034 ± 0.004	ND*	0
Ni	1.59 ± 0.07	1.53 ± 0.20	96.38
Pb	64 ± 4	43.08 ± 3.55	67.32
Zn	30.9 ± 0.7	29.18 ± 2.46	94.42
Note: ’ND - not detected
value and was expressed as a recovery percentage
(Table 4).
A combination of Tomato leaves (1573 a), Sea
lettuce (BCR - 279) and Aquatic plant (BCR - 060)
were used. Each CRM was digested and analyzed
in the same way as the samples.
3.	Results and Discussion
Tire results of the analysis were compiled into
spreadsheets to form the dataset for the database.
A data visualization software package, Tableau
(Tableau Software), was used to develop an Online
tool for users to interact with the data (Figure 2).
Users may access the database and query the data
under two headings: parameter or species. Under
the parameter heading, a given parameter can
be selected and filtered by species and partition.
Tire results for this parameter are then presented,
and can be further filtered to show all or only
specified results. Tire tool is available Online at
wwwforestenergy. ie.
The parameters that are presented in the
database are known to be important in forest
biomass supply chains. By having the net calorific
value on a dry basis, and the basic density, the
actual energy content of any fuel quantity at any
moisture content can be calculated. This is useful
for practitioners who are seasoning stacks of
forest biomass and want to estimate the energy
per stack / per load they are delivering. A high
content of ash means that less of the biomass is
combustible as a fuel and there is more ash to be
utilized/disposed at the end of the combustion
process, and so quantifying this for tree partitions
is useful. It is also important to characterize
the biomass ash melting behavior as the ash
deposition causes slagging and fouling of the
boiler system (Karampinis and Grammelis, 2016;
Obernberger, 2009). Slagging is the deposition
of sticky, molten ash on the furnace walls and
on hottest parts of the boiler system which
experience radiant heat transfer directly from
the flames from combustion; fouling takes place
in the relatively cooler parts of the system where
flue gas and fly ash cool down and form deposits,
often on the heat exchanger tubes. The Chemical
composition of biomass can determine usability
of biomass as a fuel in terms of emissions and
suitability for combustion in certain conditions.
Chlorine, Sulphur and Nitrogen contents should
be quantified and any biomass feedstock having
high concentrations of these elements should be
highlighted and omitted from the fuel mix.
Chlorine content is a concern for boiler
operators, as a high Chlorine content can cause
corrosion of the boiler. Sulphur itself is corrosive,
but a certain ration of Sulphur to Chlorine will
reduce the corrosive effects. While maintaining
this ratio is important to reduce corrosion, a
26
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
Gross Calorific Value (dry basis) MJ/kg
Species (Common)	Species (Lati n)
Alder	Ainus glutinose
BI rch	Betuta pendula
Betufa pubescens
Betula sp.	• s -yg
Eucalyptus	Eucalyptus delegatensis
Eucalyptus nitens	19.32
Hybrid poplar	Populus spp.	19 45
Lodgepole pine	Pinus contorta Dougl	|	20 01
Norway spruce	Picea abies (L.) Karst.	gg
Sitka spruce	Picea sitchensis (Bong.) Carr.	19.95
19.66
Wood
19 40
19 10
Branch
20.51
19.39
19-45___________20.69
19.80	19.80
19 28	19.68
19 43	19.50
19 98	20.76
19.87 __________20.82
19.85	20.66
Bark	Wholetree	Foliage
20.36	21.21
20.23
18 00
Bark
16.00
Species (Latin)
H Alnus giutinosa
Betula sp
Branch
H Eucalyptus defegatensis
Eucalyptus nitens
Foliage
H Picea sitchensis (Bong ) Ca... H Populus spp.
■ Pinus contorta Dougl

Wholetree
og Share Download ]=£ Full S
Fig. 2. Output of online database for gross calorific value
Note: Users canfilter the results according to species and partition, and download the underlying data.
high concentration of either Sulphur or Chlorine
could lead to emission issues (Obernberger et
al., 2006). Carbon, Hydrogen and Nitrogen are
also important elements to quantify for carbon
accounting purposes, and life cycle analysis
of biomass supply chains. This is where the
carbon released in the harvesting, chipping and
transportation of the wood fuel is evaluated to
see if there is a net benefit using the wood fuel in
terms of carbon offsetting from fossil fuels.
4.	Conclusions
The developed database tool has the potențial
to serve practitioners, planners, and researchers
working with biomass supply chains.
As more data is becoming available, it can
be added to the database to further extend the
knowledge in the industry. Tire underlying data
stored in the developed tool, can be displayed or
downloaded, so that users can perform their own
data analyses.
Tire tool is freely available online at www.
forestenergy.ie.
Acknowledgements
This study was carried out under the
SHORTFOR Project, which was funded by the
Department of Agriculture, Food and the Marine,
under the COFORD Forest Research Programme.
References
K a r a m p i n i s, E., G r a m m e 1 i s, P., 2016:
B1SYPLAN Handbook. Ist ed. Kalmar: Bioenarea.
Obernberger, L, Brunner, T, Barnthaler, G.,
2006: Chemical properties cf solid bicfuels - significance
and impact. Biomass and Bioenergy 30 (11), pp.
973-982.
Obernberger,!., 2009: Reached developments
cf biomass combustion technology and future outlook
Proceddings of the 17* European Biomass Conference,
Hamburg, Germany, ISBN 978-88-89407-57-3, pp. 20-
37, ETA-Renewable Energies (Ed.), Florence, Italy.
P h i 1 1 i p s, EL, 2011: AU Ireland Roundwood
Production Forecast 2011-2028. COFORD, Department
of Agriculture Fisheries and Food, Dublin.
2011: CRDG, Coford Roundwood Demand
Group. AII Ireland Roundwood Demand Forecast 2011-
2020. COFORD, Dublin, Ireland.
***, 2014: COFORD, Irish Forests and Renewable
Energy, Dublin, Ireland.
***, 2010: Ireland’s National Renewable Energy Action
Plan, Dublin, Department of Communications, Energy
and Natural Resources.
***, 2009a: EN 14774-3: Determination cf moisture
content - Oven dry method - Part 3: Moisture in general
analysis sample.
***, 2009b: EN 14775: Determination cfash content.
***, 2009c: EN 14918: Determination cf calorific value.
Revisia râdurilor • Anul 132 • 2017 • Nr. 1
27
Enda COATES
Waterford Institute of Technology
e-mail: ecoates@wit.ie
Brian CRONIN,
Waterford Institute of Technology
Christopher MCGURREN
Waterford Institute of Technology
Nicholas MOCKLER
Waterford Institute of Technology
Maeve KENNEALY
Waterford Institute of Technology
Eleanor OWENS
Waterford Institute of Technology
Tom KENT
Waterford Institute of Technology
Irish Wood Fuel Database - A WEB Based DataBase of Wood Fuel Parameters
Abstract
An online database has been developed which details the wood fuel characteristics of many Irish grown tree
species. The database includes values for Moisture Content at felling. Basic Density, Ash, Ash melting behavior,
Calorific value. Carbon, Hydrogen, Nitrogen, Chlorine, Sulphur, Oxygen, Arsenic, Cadmium, Chromium,
Copper, Mercury, Nickel, Lead and Zinc. The information that populates the database has been collected from
the felling and destnictive sampling of specimen trees. It is presented in an online web-based format, where
users can query parameters to view specific data as graphics, download figures, and also tables of the underlying
data, which is all freely available. The species currently represented in this database are alder (Alnus glutinosă),
ash (Fraxinus excelsior L.), birch (Betula pendula & B. pubescens), lodgepole pine (Pinus contorta Dougl),
Norway spruce (Picea abies (L.) Karst.), Sitka spruce (Picea sitchensis (Bong.) Carr.), hybrid poplars (Populus
sp.),Eucalyptus delegatensis, andEucalyptus nitens. For each species, data is presented separately for the stern,
wood, top, bark, branch, and foliage. Tire database can be accessed at www.forestenergy.ie.
Keywords; Biomass, biomass characterization, fuel quality, database
Irish Wood Fuel Database - O bază de date WEB pentru parametrii combustibililor lemnoși
Rezumat
Lucrarea de față prezintă metodologia de dezvoltare a unei baze de date ce conține detalii legate de
caracteristicile combustibililor lemnoși pentru mai multe dintre speciile forestiere caracteristice Irlandei. Baza
de date include valori ale umidității la recoltare, densității, conținutului de cenușă și a parametrilor de topire
a cenușei, valorii calorifice, conținutului în carbon, hidrogen, azot, clor, sulf, oxigen, arsenic, cadmiu, crom,
cupru, mercur, nichel, plumb și zinc. Informația care populează baza de date a fost colectată prin doborâre și
eșantionare destructivă a specimenelor de arbori. Informația este prezentată în format disponibil online, în
care utilizatorii pot interoga parametrii disponibili pentru a vizualiza datele sub formă de grafice și de unde
pot descărca grafice și tabele conținând informația în cauză, informație ce este disponibilă gratuit. Speciile
disponibile în prezent în baza de date sunt aninul (Alnus glutinosă), frasinul (Fraxinus excelsior L), mesteacănul
(Betula pendula & B. pubescens), pinul (Pinus contorta Dougl ), molidul (Picea abies (L.) Karst.), molidul de
Sitka (Picea sitchensis (Bong.) Carr ), plopii hibrizi (Pcpulus sp.), și eucaliptul (Eucalyptus delegatensis, E.
nitens). Pentru fiecare specie, datele sunt prezentate separat pentru lemnul din trunchi și vârf, coajă, crăci și
masa foliară. Baza de date dezvoltată poate fi accesată la www.forestenergy.ie.
Cuvinte cheie: biomasă, caracterizarea biomasei, calitatea combustibililor lemnoși, bază de date
28
Revisia pădurilor • Anul 132 • 2017-Nr. 1
A New M.S. Excel - V.B.A. Tool for
Postural Data Processing and
Analysis in Forest Operations
Mădălina FORNEA
1.	Introduction
To stay competitive on a dynamic market,
nowadays industries tend to automate most
of their specific processes as a result of the
constant pressure to reduce the products and
Services development cycle time, enabling this
way an improved customer satisfaction, as
well as to reduce the development and market
releasing costs with obvious benefits in terms of
competitiveness. Nevertheless, many industries
are still relying on manual labor either as a
consequence of underdeveloped technology in
their fields or due to the lack of such technology
in the underdeveloped countries.
In particular, forest operations may be
characterized by an important contribution of
manual and motor-manual labor. That’s because
the mechanization level depends to a great extent
on factors such as forest type, management
approach, terrain and climate conditions (Vusic
et al., 2013). At the same time, there is a number
of harvesting systems that are currently used
around the world in forest operations (Oprea,
2008), but many of them still make a substanțial
use of manual labor. For instance, motor-manual
tree felling and processing is a practice well
spread across the globe both, in the tradițional
forestry (Borz and Ciobanu, 2013; Ghaffariyan et
al., 2013; Ghaffariyan and Sobhani, 2007; Ignea
et al., 2017; Jourgholami et al., 2013) and short
rotation coppice (Talagai et al., 2017). In forestry,
it aims to convert the standing trees into logs that
are then extracted to the roadside using other
kind of forest equipment. Examples of operations
that involve manual labor are those of animal
logging (Borz and Ciobanu, 2013; Jourgholami et
al., 2010), manual bunching (Borz and Ciobanu,
2013), manual splitting, manual stacking, cable
yarding (Gaffariyan et al., 2010; Spinelli et al.,
2010), cable skidding (Borz, et al., 2013; Borz et
al., 2015), chute logging (Eroglu and Acar, 2007),
cable rigging (Ottaviani et al., 2011; Stampfer et al.,
2006) etc. Excepting few harvesting systems such
as those coupling harvesters with forwarders,
most of the equipment used in timber harvesting
operations still involves, under operațional point
of view, manual labor. On the other hand, forest
work is particularly difficult (Alexandru, 1997)
and dangerous. First of all, forest workers are
required to cope with difficult terrain, rigors of
open sky work and to handle heavy equipment
and tools while wearing also heavy and,
sometimes, uncomfortable protective equipment.
Secondly, they are required to work with or near
hazardous equipment that sometimes needs to be
handled in very steep terrain or at considerable
heights above the ground (Corella-Justavino et
al., 2015; Stampfer et al., 2006). In addition, they
often disregard the best practices in operations
(Borz et al., 2014c) a fact that may have serious
consequences.
Tire U.S. report on ”National Census cf Fatal
Occupational Injuries in 201^ classifies the logging
work as oue of the most dangerous due to its
difficulty level and high risk to which the workers
falling in this industry are exposed to (Bureau of
Labor Statistics, 2016). Obviously, the technical
procedures are quite complex in this industry,
requiring a high level of physiological (Oprea, 2008)
and physical workload and exposing the workers
to musculoskeletal disorders (MSD) (Calvo, 2009).
In addition, the work with power tools (Alexandru,
1997; Tsioras et al., 2014), and with other kind of
forest equipment such as skidders, forwarders and
chippers (Poje et al., 2015) exposes the workers
to other stressors such as vibration (Axelsson,
1998; Bovenzi, 1996; Bovenzi and Betta, 1994;
Rottensteiner et al., 2013; Tsioras et al., 2011)
and noise (Humann et al., 2012; Poje et al., 2015;
Rottensteiner et al., 2013).
Therefore, one of the most important scientific
parts and concerns of forest operations engineering
and management as a discipline is the forest
operations ergonomics (Heinimaim, 2007).
Ergonomie studies are often carried on with the
purpose to evaluate, classify and, if necessary, to
take corrective actions related to postural behavior
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
29
during work, aiming to tind the most convenient
way to balance the two main parts of a work
system - the human capabilities and the work
conditions - without affecting work productivity or
increasing significantly the labor costs (Vieira and
Kumar, 2004). Therefore, an ergonomie assessment
of postures taken by the workers during their
production tasks can give valuable Information
for those concerned to design or re-design work
places and tools that will help in the attempt to
maximize work performance while not exceeding
the safety level of musculoskeletal workload.
Tire internațional literature on ergonomie
methods developed and used in the assessment of
work postures is characterized by a wide variety,
with methods specifically designed for certam
research objectives (Chiasson, 2011; David, 2005).
Tire main advantages of these methods are that
they can be easily adapted to specific Industries,
depending on the scope of the ergonomie
assessment.
OWAS (Ovako Working Analysis System) is
only one of the methods currently used in postural
assessment for certain Industries or jobs. This
method is used to analyze, classify and undertake
corrective actions for the most frequent work
postures including the force exertion during the
work tasks based on an analysis carried on four
components (Karhu et al., 1977). It has been used
for assessments in various Industries, including
forest operations (Calvo, 2009; Corella-Justavino et
al., 2015), where it still has a lot of potențial.
As the work Science and the work system itself
evolved, researches and professionals concerned
with finding the right combination between the
capabilities of a worker and his job requirements,
have tried by the development and use of certain
assessment methods to test and analyze the
implications of workload and posture on worker’s
health. Initially, all the developed methods used
pen-and-paper approaches to collect the needed
data. Examples are described in studies of Karhu
et al. (1977), Keyserling et al. (1992), McAtamney
and Corlett (1993). At the same time, in work
Science applied to forest operations, the pen-and-
paper approach usually involves a great amount
of resources to collect data and there is a need
to automate as much as possible data collection
activities with obvious benefits in terms of resource
allocation (Borz, 2016). Tire same applies to data
processing and analysis where computers have a
lot of potențial in automating some of the tasks and
producing reliable results. Such an approach may
be used, for instance to process video-collected
data. To this end, video-collected data has several
advantages over the tradițional approaches because
it enables the reproduction of field operations as
they were carried out (Borz et al., 2014a), gives the
possibility to review the data at any time and, most
importantly, enables an adequate data treatment
for different purposes with virtually no restrictions
related to the separation on work tasks (Mușat et
al., 2016). Therefore, the variability of postures
taken during the operations can be addressed
properly. This is particularly useful in the research
of that job tasks characterized by rapid changes in
terms of work postures, dynamism and variability
of movements, as described in Corella-Justavino et
al. (2015). Variability in time of such tasks often
comes from the variability in size of the work
object and variability of operațional conditions.
For instance, the time spent in a given posture
when felling trees will vary in direct relation to
the tree size (Borz and Ciobanu, 2013; Ghaffariyan
and Sobhani, 2007; Jourgholami et al., 2013) while
the time spent in winching operations will vary in
direct relation to the winching distance, slope and
direction (Borz et al., 2014b). For this reason, a work
cycle or activity in the forest operations industry
may not be characterized by a constant duration
between the replications as it may be the case of
other Industries (Beheshti et al., 2015). Therefore,
in situ sampling at regular periods of time that
is further characterized by large time intervals
between the replications, as well as data analysis
based on such measurements, may produce
biased results and constitutes yet another reason
to collect data by video-recording. On the other
hand, postural data collection by video-recording
can sometimes be impaired due to some reasons
such as the gaps in the continuously collected
data reasoned by observer’s safety or by the work
conditions. Following this idea, in the tradițional
pen-and-paper approach of postural data analysis,
an observer may need to remake the observations
until a proper level of data accuracy is reached
while in the video-collected data approach he (she)
only needs to set an adequate sampling rate.
At the same time, processing and analysis of
video-collected data may be challenging (Borz
and Adam, 2015; Mușat etal., 2016) supporting the
idea of developing software tools able to process
30
Revista pădurilor • Anul 132 • 2017 • Nr. 1
such or derived data while the postural assessment
using software tools should automate operations
to a certain extent. Among the capabilities and
functionalities of existing software tools that
implement the OWAS method are the code
Identification and matching of the intervention
categories. In some cases, the software tools can
give recommendations based on the results (de
Anchieta Messias and Okuno, 2012; Ketan and
Al-Zuheri, 2008; Costa et al., 2015).
The postural assessment may also be eased
by the integration of sampled pictures for
each posture in the evaluation window. This is
particularly important to save time and effort
as presented in this study. Nevertheless, such
capabilities were not identified in the existing
software tools. Then, the developed tools should
cope with and treat the limitations of the video-
collected data approach, they should be able to
produce the relevant statistics as well as to build
databases to enable further analysis if needed.
By considering the above mentioned, the
development of software products to integrate the
premises and specifications of a certain method
or theory, can save a lot of time and money and
also can provide a better data management. There
are many examples of simple tools coming from
the forest industry (i.e. cost calculation tools) that
support forest practitioners and scientists in their
work. On the other hand, such tools need to step
up by adding value and by improving the existing
capabilities and functionalities. This often means
that new capabilities and functionalities need to
be developed and aligned to the newly identified
needs as being specific to Science and practice.
Tire added value is sometimes referred as
the improvement of scientific research by
easing its resource management. Therefore, the
transposition of a certain theory or method in
computațional code represents a path for the
development of scientific research (Lane and
Gobet, 2012) while important Science relies on
models and the software implementing them
(Joppa et al., 2013) meaning that a professional
end-user (Segal, 2004) needs to cope with modern
requirements of the scientific world by adapting
classical methods and theories to tools that can
ease the scientific research in a comprehensive
way. To this end, Segal et al. (2005) define
the so-called „reflective practitioners” as those
people concerned with the improvement of their
discipline by developing software tools.
Tire aim of this study was to develop and
test in terms of added value a software tool for
video-collected data work posture processing and
analysis by implementing the OWAS method.
2.	Materials and Methods
In order to develop a software tool for the
ergonomie assessment of work postures based on
OWAS specifications, it was mandatory to carry
on a bibliographical research that aimed to build
knowledge and a better understanding related to
the needs of such a tool.
In particular, the industries that use such
methods in the ergonomie assessment, pros and
contras, as well as the existing software tools
were benchmarked in a comprehensive approach.
The literature survey included also those
problems related to forest operations and wood
processing industry. The issues related to the
tradițional approaches were addressed, and the
existing software capabilities and functionalities
were assessed. This part of the methods section
was used to build the background of this paper
and also to sketch the targeted capabilities and
functionalities of the software product to be
developed. Based on the identified needs, and for
convenience (since many people use Microsoft
Office applications), the software tool was
developed using the Visual Basic for Applications
- V.B.A. ® development environment running
under Microsoft Excel - MS Excel ®, version 2013.
While the added value can be measured in a
number of ways, including the newly integrated
capabilities and functionalities, one key issue is
that of resource management, especially time
consumption in data processing activities. To this
end, following the release of the first funcțional
version of the software tool, a comparative study
was designed and implemented to test the added
value in terms of time resources requirements. For
this purpose, the comparison was made between
the tradițional way of doing an ergonomie
evaluation and that implementing the developed
tool (FORERGO).
Therefore, this paper was organized differently
compared to classic research papers. Firstly,
it gives an overview on the developed tool’s
interface, capabilities and functionalities, then it
develops and discuss the results of comparative
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
31
study aud, finally, it concludes on the added value
of the product.
3.	Description of Key Capabilities and
Functionalities
3.1.	Inițial Data Window
Tire software tool was built to work with
frames extracted at a certain (equal) time interval
from video files, a capability that is aligned to
the OWAS method specifications that analyses
the postures at a given time interval. Usually,
the video files can be broken into a number of
frames that stand for images sampled at a given
time interval from the original video file. To this
end, there is a number of freely available tools
able to undertake such conversions and to code
sequentially the extracted frames. Therefore, the
accuracy requirements of a given study can be
met by extracting the frames at a sampling rate
that is aligned to the study goal.
The tool is simply initialized by opening the
containing Excel workbook. As it was developed
in order to be included also other ergonomie
assessment methods, the first screen (not given
herein) introduces the user into the available
evaluation sub-tools. Here, the user may choose
the method used in the evaluation. If the OWAS
evaluation method is selected then the next
window pops up (Figure 1). It allows the user
to define a project name that has to be unique
(otherwise the tool pops up a message instructing
the user to choose another name) as well as to
define up to 10 tasks (work elements) and their
corresponding abbreviations.
This functionality is particularly helpful when
observing forest operations tasks where the
number of work elements within a work cycle
can reach such numbers (Borz et al., 2014a). Then
the user proceeds to the project data validation
that is transposed into the creation of a new sheet
named by the project name and fully formatted for
the evaluation. This sheet serves as a data storage
database for the evaluations made according to
those presented in Figure 2. It is fully updated
based on the actions undertaken by the user and
it also serves to build statistics and to allocate the
action categories specific to the method. The third
step to be undertaken under the window shown
in Figure 1 is the input of a value for the number
of frames per second. This is particularly helpful
for those projects aiming to derive also the time
spent in different work postures, work elements,
work cycles and work postures.
Tire time spent is such subdivisions is actually
calculated by using the value set for the fps
variable, the number of digital images falling
into a specific category and the declared and
attributed work phases to each analyzed image.
Based on the comments added by the user in
the next window and the updated database, oue
may choose to conduct externally other detailed
analyses as being specific to time and motion
studies.
FORERGO- Inițial data input, OWAS method
Project parametres
1. Insert project name
| project 1
2. Insert work phases names
5.Select photo folder
Fig.l. FORERGO’s inițial data window
Tire last step in this window is the one
corresponding to the selection of a folder
containing the digital images to be analyzed.
Once the folder was selected, the user needs to
click on the arrow button located to the bottom
right corner to move on to the evaluation window.
This action builds a list of strings into the
database that is used afterwards to locate the user
between the analyzed images each time a given
image is shown on the screen.
32
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
3.2.	The Evaluation Window
The evaluation window enables the users to
perform a number of tasks that are specific to
most of the software products implementing
the OWAS method, but it gives also newly built
capabilities and functionalities. Firstly, when the
window is shown, the upper part indicates in
green the path and the name of the first or current
image that is shown within the main window.
This functionality helps the user to go back or
forth to a given image and to analyze (reanalyze)
it as mentioned below.
Depending on the clarity and the visibility of
the image, the user may choose to magnify it or
to reduce its size using the Controls placed in the
upper right corner. One of the new functionalities
is that allowing the user to navigate between the
images loaded using the previous window. This
functionality is supported by a dedicated code
written to characterize the clicking events of the
two arrow buttons located in the lower left side
corner of the window. This way, the user may
navigate between the loaded images, may choose
his options based on the evaluation buttons and
may reconsider some already processed images
by searching them.
Tire database behind the window is dynamic,
in the sense that once the user chooses and
validates given parameters they are written in
the corresponding space until the user chooses
to modify them. In addition to the possibility to
select a work phase and a work cycle for each of
the analyzed images using the combo and the text
boxes located in the left bottom corner, the user is
enabled also to make observations or comments
to each of the analyzed body segments using
the corresponding text boxes. Once a decision
is made on a given image that was analyzed, the
user validates the data using the “Validate image
data” button. This event triggers the modification
of the background database.
It should be montioned here that FORERGO
was specifically designed in order to cover
other situations that may occur, based on those
described by Corella-Justavino et al. (2015). An
example is that specific to those images that
may be interpreted as being not valid as they
are incomplete or are showing only a part of
the worker’s body. For this purpose, FORERGO
implements a special value for each body segment
as well as a special action category named “0”.
They enable the user to partially evaluate an
image, as it can be used, for instance, in a time and
motion study but also it helps to exclude those
images form the ergonomie postural analysis.
For convenience, most of the buttons were
Fig.2. FORERGO’s evaluation window
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
33
built as suggestive as possible. The images used
to represent typical postures as being specific
to OWAS analysis, were built using the free
software tool MakeHuman (available at: www.
makehumancommunity.org/), based on the
description provided in Helander (2005). As
shown in Figure 2, each body segment was
included as typical for an OWAS analysis and a
supplementary button was added to cover the
above-mentioned problems related to inconsistent
images.
3.3.	Building Statistics and Showing Results
FORERGO also provides a simple way to build,
compute and showbasic statistics of the ergonomie
postural assessment under the framework of
OWAS. For a more detailed analysis, the user may
work on the database that is automatically built
and updated in the background (MS Excel sheets).
For basic statistics on the ergonomie
assessment, FORERGO provides functionalities to
build and show category frequencies, proportions
and time percentages only by selecting the
appropriate buttons and chart types.
Frequency of a given category is the result of
identifying and counting the number of identical
entries, from 0 to 4 (Figure 3). Tire proportions
are computed by dividing the frequency value for
each category by total number of category entries
and multiplying the result by 100.
Fig.3. FORERGO’s statistics building function
Time consumption for each postural category
is computed by multiplying two numerical values,
namely the category frequencies and the time for
each postural category followed by the result’s
division by 100.
4.	FORERGO’s Added Value in Terms of
Time Consumption
4.1.	Design cf the Comparative Study
In order to emphasize the FORERGO’s added
value in terms of time consumption, a comparative
study has been designed and implemented in two
experimental setups: FORERGO as a modern
approach vs. pen-and-paper as a tradițional
approach.
By this study, time consumption was used
as the main variable describing the resource
requirement intensity. For this purpose, a set of
500 digital images characterizing the work tasks
specific to tradițional manual handling of wood
were selected randomly from a set containing
more than 5000 images. A number of 50 images
were randomly selected from the inițial selection
set and were used in the analysis that followed
the specific paths of both approaches: modern
vs. tradițional. Therefore, the pen-and-paper
tradițional approach took into consideration all
of the phases required by postural assessment
including the development of paperwork needed
to gather and analyze the data. Tire paperwork
needed to analyze the data was developed prior
to the implementation of the comparative study,
therefore this step was not included in the study
even if, for given setups, it could take additional
time and resources such as paper sheets. Basically,
in this setup, one researcher analyzed the images
shown on a computer screen, wrote the codes
for each body segment on a paper sheet, then
concluded the study by identifying the action
categories in a printed matrix and by writing
down all the codes on the sheets. Statistical
analysis was excluded from the tradițional study
as the FORERGO builds those statistics in an
automated way and the comparison did not make
any sense as the statistics are built in few time.
In the modern approach, the same images
were analyzed following the analysis and
computațional steps presented in this paper.
In both experimental setups, the time needed
to analyze each image was counted at a one
second accuracy by a continuous timing method
(Bjorheden et al., 1995) using a professional
stopwatch. In addition, the time needed to
synthetize the codes and to extract the action
values for each category were separately timed
for the pen-and-paper approach. Timing results
34
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
of each approach were translated and processed
into a MS Excel sheet by applying basic operations
to compnte the time differences, to develop
descriptive statistics and to plot graphically the
results.
4.2.	Results cfthe Comparative Study
The results showing the added value of using
FORERGO compared to the tradițional approach
are shown in Figure 4 and in Table 1. The descriptive
statistics shown in Table 1 stand for obvious
differences in terms of time consumption between
the two approaches. For instance, individual
analysis of each image took in average almost
13 seconds when using FORERGO and almost 30
seconds in the tradițional approach. This indicates
that using the tradițional approach would take,
in average, more than 2.3 times more time to
analyze individual images. Standard deviations
in both cases indicate the variability in this task
suggesting that in the case of FORERGO this task
is less variable in terms of time compared to the
tradițional approach as a result of automation.
Tire same may be observed in the data ranges as
being specific to the two approaches. In the case
of FORERGO it was of 29 seconds while in the
case of tradițional approach it was of 49 seconds
(not shown in the Table 1). Both, minimum and
maximum time consumptions to analyze a given
image were smaller when using FORERGO.
On the other hand, the individual image
analysis was responsible for a share of about
38% of the total analysis time in the tradițional
approach. Also, matching the intervention
categories took between 3 and 66 seconds, as
this activity was fully manual. Obviously, here
may be one of the greatest benefits of using the
developed tool as it automatically assigns and
extract the intervention categories.
Altogether, image analysis and category
matching took more than 50% of the total study
time in the tradițional approach. Globally, the
time consumption in the tradițional approach
was almost 4 times higher compared to the
modern approach as shown in Figure 4, a result
that clearly shows the benefits of using the
developed software tool. If only the time spent in
image analysis is taken into consideration then
the tradițional approach took almost 2.3 times
more time resources than the modern approach.
4500
S 4000
C 3500
3000
| 2500
g 2000
8 1500
u
E 1000
H 500
0
Tradițional [s] FOROWAS [s]
Approach
Fig.4. Comparison of the time consumption as being
specific to the two tested approaches
As the experiment was setup and conducted by
the author of this study, most of the differences
found in the presented figures come from the time
needed to alternatively focus the researcher’s at-
tention to the computer screen to identify the
posture of each body segment followed by the fo-
cus of attention to the paper sheet to write down
the results.
While it is a pure speculation, as this study co-
vered the analysis and processing of only 50 di-
gital images, it is possible for a researcher using
the tradițional approach to get tired very soon as
a consequence of the frequent refocus of his (her)
attention between a computer screen or other
media to the paper sheets. Also, the results of this
comparative study are indicative. To this end,
for conclusive results and improved estimations,
Table 1
Results of the comparative study
Undertaken task	Tradițional approach				Modern approach			
	tmin	tmax Sum	Average+St. dev.	%	tmin	tmax Sum	Average±St. dev.	%
Image analysis (s)	11	60	1477	29.54 ± 10.55	37.6	1	30	630	12.60 ± 6.22	-
Matching intervention categories (s)	3	66	542	10.84 ± 9.36	13.8	-	-	-	-
Other Activities (s)	-	-		48.7	-	-	-	-
Total analysis and processing time (s)		393;	5			988		
Revisia iadurilor • Anul 132 • 2017 • Nr. 1
35
the two approaches should be tested by a greater
sample of users to cover other variability factors
including their perception as described in Mușat
et al. (2016).
5.	Conclusions
In this study, a tool for postural evaluation
as being specific to ergonomie assessment was
developed and tested. The main purpose of
FORERGO as a software tool was to provide an
improved resource management by easing the
process of data processing and analysis while
incorporating also other functionalities and
capabilities aligned to the current needs in the
field.
As a significant step up, with obvious benefits
in research tasks in terms of resource allocation, it
allows digital image integration in the assessment
window. This capability removes the necessity
to switch the researcher’s attention and focus
from the screen or other media to paper sheets
or other tools to process the data. Also, it has the
capability to use specific parameters such as the
number of frames per second enabling this way
the computation of the time spent by a worker in
a certain posture, work element or task.
Relative to the tradițional approach, another
benefit of using FORERGO was the automation
of those time-consuming activities such as
identifying the postures codes, matching the
intervention categories, computing the category
frequencies, proportions and time percentages.
In addition, FORERGO builds and dynamically
maintains a background database that can be
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Tire author would like to thank prof. Stelian
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Eng. Mădălina FORNEA
Department of Forest Engineering, Forest Management Planning and Terrestrial Measurements,
Faculty of Silviculture and Forest Engineering, Transilvania University of Brașov, Șirul Beethoven
No. 1, Brașov 500123, Romania
e-mail:fornea.madalina@unitbv.ro
A New M.S. Excel - V.B.A. Tool for Postural Data Processing and Analysis in Forest Operations
Abstract
As described by many studies, forest operations have always been ones of the most difficult and hazardous
jobs, requiring a careful design of tools, workplaces and technical procedures. Postural assessment of a job is an
important field of ergonomics. The ergonomie assessment of work postures may require a great amount of data
to be collected, processed and analyzed, involving significant resources. To ease such tasks, IT applications may
be developed and used to process and analyze data in less time and to increase the accuracy of results. OWAS
38
Revisu pădurilor • Anul 132 • 2017 • Nr. 1
(Ovako Working Posture Analysis System) is one of the most used methods aiming to evaluate the risks to work-
related disorders. In the last years, a number of applications framed around OWAS have been developed but
the field of forest operations requires more specific parameters. With the help of Microsoft Excel’s Visual Basic
component (VBA), an application (FORERGO) was developed in order to facilitate the postural analysis in such
jobs. Based on frames extracted from video files, the application may be used to compute also the time spent
in different postures. After describing the main capabilities of the developed software tool, this paper presents
the results of a comparative study, mainly focused on resource requirements for two approaches of the OWAS
method such as the tradițional pen-and-paper and FORERGO emphasizing obvious benefits of using the tool
instead of the tradițional approaches.
Keywords: forest operations, ergonomics, postural assessment, efficiency, data processing, automation
Unealtă M.S. Excel - V.B.A. pentru procesarea și analiza datelor de natură posturală în operații
forestiere
Rezumat
După cum se descrie în multe studii, operațiile forestiere au fost întotdeauna unele dintre cele mai dificile
și periculoase activități, necesitând un design atent al uneltelor, locurilor de muncă și a procedeelor tehnice.
Evaluarea posturală a unui tip de muncă reprezintă o latură importantă a ergonomiei care poate necesita
colectarea, procesarea și analiza unor seturi mari de date, implicând resurse substanțiale. Pentru a ușura astfel
de activități, pot fi dezvoltate și utilizate aplicații software pentru a procesa și analiza datele în timp mai scurt,
precum și pentru a crește acuratețea rezultatelor. OWAS (Ovako Working Posture Analysis System) este una
dintre cele mai utilizate metode ce vizează evaluarea nivelului de expunere la riscuri de îmbolnăvire profesională,
în ultimii ani, s-a dezvoltat un număr de aplicații software ce implementează metoda OWAS, dar pentru analizele
specifice operațiilor forestiere, astfel de aplicații necesită includerea unor capabilități suplimentare. Utilizându-
se Microsoft Excel și componenta V.B.A. specifică acestuia, s-a dezvoltat o aplicație (FORERGO) pentru a se
facilita analiza posturilor de muncă în astfel de activități. Pe baza unor imagini extrase din înregistrări video,
aplicația poate fi utilizată pentru a calcula inclusiv timpul consumat în diferite posturi de muncă. După descrierea
principalelor funcționalități ale uneltei software dezvoltate, lucrarea de față prezintă rezultatele unui studiu
comparativ care s-a realizat pentru a se identifica consumul de resurse pentru două abordări ce utilizează metoda
OWAS precum cea tradițională și cea bazată pe utilizarea aplicației FORERGO, punând în evidență beneficiile
evidente ale utilizării aplicației dezvoltate în locul abordării tradiționale.
Cuvinte cheie: operații forestiere, ergonomie, evaluare posturală, eficiență, procesarea datelor,
automatizare
Revista pădurilor • Anul 132 • 2017 • Nr. 1
39
Application of PERT & CPM for
Forest Utilization Planning
Majid LOTFALIAN
Mahboobe SABZI
Aii Hosseini YEKANI
Saba PEIROV
1.	Introduction
Increase of technical, economic, political
and social complexity is one of the important
aspects in the technology development. Projects
usually involve a collection of extensive, costly
and highly risky commitments which should be
finished with a defined budget during a certain
time and according to an expected efficiency level
(Williams, 1995), therefore, a project manager
should be able to identify and then evaluate the
uncertainties of the project and ultimately control
them in order to achieve success in the project
(Amiri, 2013).
Working in forest is very difficult and
overwhelming and it is also associated with
frequent limitations including shortage of human
force, loss of trained subjects, loss of professional
machines, high costs of buying machines, duration
limitation for working in forest, ruggedness of
some tracks, topography, costly procedures etc.
On the other hand, while performing all the forest
utilization projects, consideration of timetable
and accurate scheduling of operațional phases
causes timely utilization and valuable time, cost
and financial and human resources saving, so
that the longer the project time period, the less
certainly the finishing time and costs could be
estimated.
Tlius, optimum and helpful management
planning methods, scheduling, assessment
and coordination should be used in the field of
management for utilization procedures. In this
context, modern methods such as PERT and
CPM could be used (Soltani et al., 1999). PERT
and CPM are majorly designed for planning and
control purposes (Chizari and Amirnezhad, 2000).
PERT was designed to use a statistical method
for estimating the possible time of doing a task
(Haj Shir Mohammadi, 1999). It is the fastest and
the most common method in large-scale projects
planning and control (Azaron et al., 2005, Chen
and Chang, 2001).
PERT was developed in 1950 so as to help
managers with planning and managing large scale
and important projects. These days, it is widely
used in various industrial and service units. Using
this method, managers could gain the following
capabilities (Azaron et al., 2006; Stevenson, 2002):
- appropriate networks graphs expressing the
situation of doing tasks;
-	acceptable estimation of project finishing time;
-	analysis of criticai activities;
-	delay analysis of project tasks without affecting
total time of the project.
Tire Criticai Path Method (CPM) is one of the
important tools applicable in project planning
and control. It includes the determination
of criticai path, criticai activities and criticai
incidents in a project network by considering
the earliest possible finishing time of the project.
In project management and control, when the
time of activities is certain, application of classic
techniques such as CPM will be an appropriate
tool in project planning and control (Krajewski
and Ritzman, 2005).
Chen and Hsueh (2008) provided an algorithm
for forward and backward pass calculation in
a CPM network. In this algorithm, the project
criticai path was determined based on a linear
programming model and a number as a criticality
level was attributed to each available path in the
CPM network.
Chizari and Amirnezhad (2000) investigated
the application of PERT and CPM in project
management for planning, understanding of
management responsibilities and determination of
the realistic time. Results showed how much extra
cost should be paid according to the definition of
criticai paths using PERT and CPM in order to
reduce the time of doing different activities.
Asghari et al. (2004) carried out a study about
project planning, control and coordination
between time and cost using the Criticai Path
Method (CPM). In their study, besides the
investigation of characteristics related to Criticai
Path Method (CPM) and the determination of
criticai activities, a cost-time curve was also
suggested, and subsequently, the minimum cost
limit (i.e. direct and indirect costs) was obtained.
Tire results indicated that, in any conditions, cost
would not be reduced with increasing time, since
40
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
when time increases, effect of indirect costs would
be greater and thereafter would lead to improved
total project cost.
Jebel Ameli and Saeedi (2007) examined
the development of an information system in
project planning and control by applying the
CPM. They obtained results such as help in a fast
implementation (without reworking) of CPM by
project planning and control sector; possibility
of adding and updating the date; determination
of project starting activities and updating buffers
situation in system and following up their
situa tion; creation of a context in order to facilitate
informative and operațional performance of CPM.
In timber harvesting operations, Oprea and
Borz (2007) used the CPM and MPM (Metha
Potențial Method) to allocate, distribute and
operationalize timber harvesting operations
based on time constraints respectively activity
timing and overlapping for timber harvesting
blocks.
Yousefi-Nezhad Attari and Neishabouri Jami
(2009) mentioned that the lack of a valid criticai
methodtolimitthe resources not only has disturbed
the extensive use of principal path programming
software in management procedures, but also has
made the basis of any sophisticated investigation,
cost or base time analysis of CPM unstable in the
structure research planning. Therefore, it seems
necessary to develop an initiated and totally
automated method for CPM with limit resources
which is called a simulated-base planning system.
Considering that forest logging is an important
part which links biological to industrial
production, in this study, we have tried to manage
the forest utilization operations costly and timely
using PERT and CPM methods, and we have also
tried to determine those operations acting as
bottlenecks based on these methods.
2.	Materials and Methods
2.1.	Study Location
Tire studied forest, called district 1 - Darab-Kola
is located about 15 km east of Sari city. We have
selected a parcei for this study in which the team
included one chainsaw-man, two chainsaw-man
assistants, one supplier and a machine deriver.
The harvested volume and the number of trees
were 1600 m3 and 311, respectively.
Tire used equipment included a rubber-tired
skidder, a tracked skidder, a tractor and GMC
machines. In this study, common project planning
methods such as the Criticai Path Method
(CPM) and Program Evaluation and Review
Technique (PERT) were used (Sadri and Sakaki,
2004). Different tasks as being specific to forest
operations are shown in the Table 1.
Table 1
Tasks taken into study
No.	Code	Activity	No.	Code	Activity
1	Al	Workers’ safety tools and provision of work tools	23	C6	Marking logs and cut waste
2	A2	Workers’ planning	24	CO	Volume re-measurement Official administration procedures,
3	A3	Official request for sending out the tree marking team	25	Dl	reporting volume re-measurement proceedings to administrator
		Sending out the administrative tree marking		D9	Determining the contractor and
		team to determine the harvesTable volume			providing tender offer time
5	A5	Presentation time of tree marking team	27	D3	Provision of bucking license
6	A6	Adjusting the marking documents	28	D4	Providing the equipment
7	A7	Going through official administration procedures	29	D5	Workers’ planning
8	A8	Going through official procedures	30	DO	Bucking
9	A9	Issuance of cutting license	31	El	Adjusting the bucking proceedings
10	A10	Cutting permission	32	E2	Reporting the proceedings to the administrator
11	AII	Tender offer time	33	E3	Providing the tools
12	Al 2	Determining the contractor	34	E0	Extraction
13	A0	Tree cutting	35	FI	Providing the machines
14	Bl	Determination of skid trails	36	F2	Personnel
15	B2	Map surveying	37	F0	Primary transportation
16	B3	Constructing the trails in the field	38	G0	Sales and marketing
17	B0	Mapping	39	HI	Temporary storage at landing
18	CI	Reporting cutting to the administrator	40	HO	Loading
19	C2	Providing operation team equipment	41	11	Providing the personnel and equipment
20	C3	Mission tab	42	12	Issuance of transportation permission
21	C4	Providing vehicles	43	10	Secondary transportation
22	C5	Landowner’s share payment			
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
41
2.2.	Solving the Question Using CPM Parameter
in QSB Scftware
In QSB software, input data were completed
by “SELECT CPM DATA FIELD” option and then
by solving the question in CPM environment.
The next step used the outputs of criticai path
program such as the earliest start time and the
latest start time to calculate the earliest finish
time and the latest finish time.
2.3.	Solving the Question Using PERT Parameter
in QSB Scftware
To solve the problem by using the PERT
parameter and to estimate the required time for
each activity, a random variable with possibility
assumes that the time needed for each activity is
a random variable with a normal distribution
(Formulas 1 and 2).
t = a+4(m)+ba+4 (m)+b	(i)
6
Standard deviation:
b-ab-a b-ab-a
sd = ——7—Z—7"	(2)
6	6	6	6	v 7
Tire project costs under the assumptions of
normal and criticai States were mentioned in
Table 2. Tire needed triple time for PERT model is
proposed, as well.
Table 2
Utilization project costs (in short)
Activity Code	Optimistic time (days)	The most Possible time (days)	Pessimistic time (days)	Normal cost (Dollar)	Prerequisite activity
Al	4	4	4	250	-
A2	1	1	1		-
A3	2	2	2		-
A4	10	15	20		A3
A5	8	15	20	300	-
A6	4	5	10		A4
A7	5	7	10		A6
A8	15	15	25		A7
A9	10	15	20	12.5	A8
A10	2	2	2		A9
All	10	20	30	12.5	-
A12	1	2	3		All
AO	20	20	30	237.5	A10
Bl	5	5	7	10	A0
B2	3	3	3	50	Bl
B3	30	50	70	2500	B2
of distribution is considered in order to measure
the expected time for each activity through a
certain formula.
Optimistic estimate is shown as an “a” which
is the least time needed for each activity; when
everything would have been done fully and on
time, it would come true. This is the lower limit
of the possibility distribution.
Tire most possible estimation is shown as “m”.
It suggests the time needed for each activity under
a normal condition and it is the top of possibility
distribution.
Pessimistic estimate shown as “b” suggests
the time needed for each activity under the most
unfavorable condition and it is the highest limit of
possibility distribution. Thus, the time needed or
the time mathematical expectation (t) of a project
3.	Results
3.1.	CPM Model Results
Results of this model include inputs of CPM
model that have been analyzed in a normal time
frame. Tire inputs of CPM model are shown in
Table 1. Data analysis in terms of normal time is
given in Table 3. As shown, finishing time and
the number of criticai paths have been estimated
to 229 days and 3, respectively. There are 43
key activities in Table 3 which have their own
analysis.
For instance, activity number 1 (Al) includes
workers’ safety tools and provision of work tools.
Al is not considered as being a criticai activity
since it is the activity that triggers the following
events and activities.
42
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
On the other hand, as it is a kind of activity
which does not need any prerequisites, the earliest
start time cannot be the same as the project start
time. Tire earliest finish time of activity 1 has
been considered to be of 4 days since it does
not need any prerequisites. Therefore, the latest
finish time of this activity has been considered to
be 4 days before finishing the activity or the 225th
working day. Accordingly, the latest finish time
is the last day of the project i.e. the 229th working
day. Hence, the time interspace of this activity is
225 days.
more concentration since if one of these is carried
out with delay, it will affect the project. The path
which the mentioned activities are placed on is the
criticai path and managers should give it special
attention. In this procedure, the time required for
activity A4 includes 15 days. As its prerequisite
activity is activity A3 and also its earliest finish
time is 2 days, the earliest start time for activity
A4 is 17 days. Also, the earliest finish time and the
latest finish time are 2 and 17 days, respecțively.
Finally, the interspace of this activity is considered
0 which is the result of the subtraction of the latest
Table 3
Analysis of CPM model inputs (in short)
Analysis of Forest Utilization (using normal time)
No.	Activity Code	Criticai path	Average time	The first start	The first finish	The last finish	The last start	The first start the last start
1	Al	No	4	0	4	229	225	225
2	A2„	No	1	0	1	229	228	228
3	A3	Yes	2	0	2	2	0	0
4	A4	Yes	15	2	17	17	2	0
5	A5	No	15	0	15	229	214	214
6	A6	Yes	5	17	22	22	17	0
7	A7	Yes	7	22	29	29	22	0
8	A8	Yes	15	229	44	44	29	0
9	A9	Yes	15	44	59	59	44	0
10	A10	Yes	2	59	61	61	59	0
11	All	No	20	0	20	227	207	207
12	A12	No	2	20	22	229	227	207
13	A0	Yes	20	61	81	81	61	0
14	Bl	No	5	81	86	220	215	134
15	B2	No	3	86	89	223	220	134
16	B3	No	3	89	92	226	223	134
Project finishing time: 229 days.
Total cost: 31827.5$ (cost of criticai path: 1887.5$).
No. of criticai paths: 3.
Activity A3 is the starting point of the criticai
path. Interpretation of activities 2, 5,11,12, 14, 15,
16, 17, 19, 21, 22, 25, 26, 28, 29, 33, 34, 35, 36, 37,
38, 39, 40, 41, 42 and 43 are the same as activity
1 since these ones do not need a prerequisite
activity, so they could be carried out while other
activities are ongoing. Since A3 (Official request
for sending out the tree marking team) is the start
point of the criticai path, it is essential to start and
finish at the considered time, because any gaps
in work could disturb the working procedures.
Criticai activities include A3, A4, A6, A7, A8,
A9, A10, A0, CI, C3, C6, C0, D3, DO, El and E2.
Their interspace is equal to 0 and they require
start time from the earliest start time. Analysis of
activities A3, A4, A6, A7, A8, A9, A10, A0, Cl, C3,
C6, C0, D3, DO, El and E2 are interpreted in the
same way. Tire criticai path of finished activities
is shown in Figure 1. In this study, three criticai
paths for the forest utilization operations were
taken into software analysis (Table 4). The criticai
path No. 1 includes criticai activities A3, A4, A6,
A7, A8, A9, A10, A0, Cl, C3, C6, C0, D3, DO, El
and E2. Tire criticai path No. 2 consists of criticai
activities A3, A4, A6, A7, A8, A9, A10, A0, Cl, C3,
DO, El and E2. Tire criticai No. 3 includes criticai
activities A3, A4, A6, A7, A8, A9, A10, A0, C0, D3,
DO, El and E2.
Revisia pădurilor • Anul 132 •2017" Nr. 1
43
Fig- 1- Forest utilization project network with 43 activities.
Table 4
Criticai paths of forest utilization in CPM (in short)
	 Criticai Paths of Forest Utilization (using Normal Time)			
No.	Criticai Path 1	Criticai Path 2	Criticai Path 3
1	A3	A3	A3
2	A4	A4	A4
3	A6	A6	A6
4	A7	A7	A7
5	A8	A8	A8
6	A9	A9	A9
7	A10	A10	A10
8	A0	A0	A0
9	CI	CI	CO
10	C3	D3	D3
11	C6	DO	DO
12	CO	El	El
Project finish time:	Project finish time:	Project finish time:	Project finish time
229 days	229 days	229 days	229 days
Project total cost: 31827.5$ (cost of criticai path: 1887.5$)
No. of criticai path: 3
3.2.	Results cfPERT Model
Primary data include prerequisite activities,
the most optimistic time of each activity, the most
pessimistic time of each activity and the most
probable time of each activity. These figures are
shown in Table 5. The input data, activity time,
the earliest start time, the latest finish time, the
earliest start time, the latest start time and inter-
space time were calculated using the criticai path
software while analyzing the data. The project
finish time and the number of criticai paths were
estimated to 229 and 3 respectively, as shown in
Table 6.
Regarding the available data, the criticai path
network for the PERT model was provided using
the interest software (Figure 2). Criticai activities
and criticai paths are presented in Table 7.
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Revisia pădurilor • Anul 132 • 2017 • Nr. 1
Table 5
Primary inputs of PERT model (in short)
No.	Activity Code		Pessimistic time (b)		The most possible time (m)			Optimistic time (a)	Immediate Predecessor	
1		A1	5			4		4		
2		A2	1			1		1		
3		A3	2			2		2		
4		A4	15			15		15	A3	
5		A5	15			15		15		
6		A6	5			5		5	A4	
7		A7	7			7		7	A6	
8		A8	15			15		15	A7	
9		A9	15			15		15	A8	
10		A10	2			2		2	A9	
11		A11	20			20		20		
12		A12	2			2		2	A11	
13		A0	20			20		20	A10	
14		B1	5			5		5	A0	
15		B2	3			3		3	B1	
16		B3	3			3		3	B2	
									Table 6	
Analysis of PERT model inputs (in short)										
No.	Activity Code	On critical path	Average time	First start	First finish	Last start	Last finish	First start- last start	Time scattering	SD
1	A1	No	4	0	4	225	229	225	3-time estimate	0
2	A2	No	1	0	1	228	229	228	3-time estimate	0
3	A3	Yes	2	0	2	0	2	0	3-time estimate	0
4	A4	Yes	15	2	17	2	17	0	3-time estimate	0
5	A5	No	15	0	15	214	229	214	3-time estimate	0
6	A6	Yes	5	17	22	17	22	0	3-time estimate	0
7	A7	Yes	7	22	29	22	29	0	3-time estimate	0
8	A8	Yes	15	29	44	29	44	0	3-time estimate	0
9	A9	Yes	15	44	59	44	59	0	3-time estimate	0
10	A10	Yes	2	59	61	59	61	0	3-time estimate	0
11	A11	No	20	0	20	207	227	207	3-time estimate	0
12	A12	No	2	20	22	227	29	207	3-time estimate	0
Project finish time: 229 days Number of criticai path: 3										
Fig. 2, PERT model network
Revista pădurilor • Anul 132 • 2017 • Nr. 1
45
Table 7
Forest utilization criticai paths in PERT
Forest Utilization Criticai Paths			
No.	Criticai Path 1	Criticai Path 2	Criticai Path 3
1	A3	A3	A3
2	A4	A4	A4
3	A6	A6	A6
4	A7	A7	A7
5	A8	A8	A8
6	A9	A9	A9
7	A10	A10	A10
8	A0	A0	A0
9	CI	CI	CO
10	C3	D3	D3
11	C6	DO	DO
12	CO	El	El
13	D3	E2	E2
14	DO		
15	El		
16	E2		
Finish time:	229	229	229
SD:	0	0	0
4.Discussion
According to the analysis of CPM, the
calculated time and cost were 229 days and
31827.5$, respectively, out of which 1887.5$ were
allocated to the criticai path. Tire used software
provides this capability enabling this way the
development of various projects based on time
allocation.
Tire favorable time for the project studied
herein was considered to be 240 days. Based on
input data and on those 240 days, the possibility
percentage of activities was calculated as 100%,
since the normal time in this case was of 229 days.
Using the methods presented herein, it is
possible to save money and time. For instance,
the time could be reduced by 29 days while the
costs could be reduced by 90$. Also, the proposed
time (200 days) of input data has been reduced to
198 days. Moreover, the project total cost in this
case was of 31737.5$.
Using PERT, the project total time was set to
229 days which included three criticai paths, and
similar to the CPM, it used criticai activities in
terms of priority. According to this model, all
of the criticai activities will finish in 229 days.
In the simulation part of PERT, when using
the functionality "use dtfaull random seed”, the
project favorable time was considered to be 200
days. This simulation has been evaluated by
considering 1000 activities.
This study revealed that the forest utilization
operations in terms of cost and time could be
managed using PERT and CPM approaches,
eventually resulting in operațional improvements
by favorable effects associated with efficiency
increments. In addition, by using these
management methods, we could identify and
avoid barriers during the work procedures.
References
A m i r i, M., 2013: Provision cf a method to rank risks
cfprcject activities using fuzzy PERT and CPM network.
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A s g h a r i, O., S a k a k i, S.H., Y a v a r i, M.,
S o 11 a n i, F., 2004: Prcject planning and control and
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A z a r o n, A., P e r k g o z, C., S a k a w a, M., K a t o, K.,
M e m a r i a n i, A., 2006. A multi-otjective resource
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C h e n, S.M., C h a n g, T.H., 2001: Finding
multiple possible criticai paths using fuzzy PERT, IEEE
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transactions on system, man and Cybernetics-Part B:
Cybernetics, 31, pp 930-937.
Chen, S.P., H s u e h, YJ., 2008: A simple approach
to fuzzy path analysis in prcjects networks, Applied
Mathematical Modeling, 32, pp 1289-1297.
C h i z a r i, A.H., A m i r n e z h a d, H., 2000: Prcject
management cf constructing a corn drying unit using
PERT and CPM. Publication of Agricultural Economics
and Sustainable Development.
H a j S h i r M o h a m m a d i, A., 1999: Prcject
management and control: application cf CPM, PERT, PN
and GERT, University Jahad of Esfahan Industrial Unit
Pub, 425 p.
JebelAmeli, M.S., S a e e d i, H., 2007: Development
cf an Information system for prcject planning and
control with CPM chain criticai approach. 5th National
Industrial Management Conference, Tehran, Iran
University of Science and Technology.
Krajewski,LJ,Ritzman,L.P.,2005: Operațional
management: process and value chains, Prentice-Hall,
New Jersey.
Op r e a, L, B o r z, S.A., 2007: Organizarea șantierelor
de exploatare a lemnului [Planning cf Timber Harvesting
Sites]. Transilvania University Press, Brașov.
S a d r i, M., S a k a k i, S.H., 2004: Effective network
methods in exploration prcjects management, Iran
Mining Engineering Conference, 314 p.
S o 11 a n i, G.H., Z i b a y i, M., K e y k h a, A.A., 1999:
Application cf mathematical planning in Agriculture,
Agriculture Research and Training Institute Pub, 428 p.
Stevenson, W.J., 2002: Gperation Management,
7* Ed, McGraw-Hill, English Book, Online.
Williams,!., 1995: A classfed bibliography
cf recent research relating to prcject risk management,
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Y a k h s k e s h i, A., 2002:. Knowledge, Conservation
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Majid LOTFALIAN
Associate Professor, Forestry Department, Sari University of Agricultural Sciences and Natural Resources,
mlotfalian@sanni.ac.ir
Mahboobe SABZI
M.Sc. graduated, Sari University of Agricultural Sciences and Natural Resources,
sabzi_mahbobeh@yahoo.com
Aii Hosseini YEKANI, * Corresponding author
Assistant Professor, Department of Agricultural Economics,
Sari University of Agricultural Sciences and Natural Resources,
s.a.hosseini@sanm.ac.ir
Saba PEIROV
PhD student, Forest engineering, Sari University of Agricultural Sciences and Natural Resources,
peyrovsaba@gmail.com
Application of PERT & CPM for Forest Utilization Planning
Abstract
This study was carried out in order to test the applicability of PERT and CPM in forest utilization planning of
Darab-Kola forests. Firstly, the logging data of one cycle was collected and it was then processed and prioritized.
Then, the software inputs were determined. In the next stage, we ran the inputs in QSB software to obtain
simulation results. Data analysis showed that a duration of 229 days needed as a normal time to complete the
project can be reduced to 171 days using an appropriate management so that the quality of work would remain
the same. However, by using the tradițional path of utilization, it takes much more time than that estimated.
Accordingly, the project costs increase, an effect that can be properly managed by an accurate logging planning.
This study suggests that the time and costs of forest utilization operations could be managed using PERT and
CPM to obtain an appropriate outcome, by applying them in order to improve the work as well. Application of
the above-mentioned methods could have a favorable effect on increasing the efficiency of production. Moreover,
such management methods can identify and remove the bottlenecks on the pathway of forest utilization.
Keywords: QSB, forest utilization, criticai activities, wood extraction
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
47
Utilizarea PERT și CPM în planificarea operațiilor forestiere
Rezumat
Studiul de față s-a realizat pentru a se testa aplicabilitatea tehnicilor PERT și CPM în planificarea operațiilor
forestiere pentru un studiu de caz aplicat zonei forestiere Darab-Kola. în primul rând, s-au colectat date pentru
un ciclu de recoltare, date care s-au utilizat pentru procesare și prioritizarea activităților. Apoi, s-au determinat
intrările necesare pentru prelucrarea asistată de calculator a datelor în programul QSB în vederea obținerii
rezultatelor simulării. Analiza datelor a pus în evidență o durată de 229 zile necesare ca durată normală de
timp pentru completarea proiectului, durată ce poate fi redusă la 171 zile prin utilizarea unui management
adecvat, astfel încât calitatea prestării muncii să rămână aceeași. Cu toate acestea, utilizarea căii tradiționale de
implementare a operațiilor forestiere necesită mai mult timp comparativ cu cel estimat cu efecte în creșterea
costurilor, efecte ce pot fi controlate printr-o planificare adecvată a operațiilor de recoltare a lemnului. Studiul
de față sugerează că timpul și costurile asociate cu operațiile de recoltare ar putea fi gestionate utilizându-se
tehnicile PERT și CPM pentru a obține rezultate adecvate, ca și prin aplicarea acestora pentru îmbunătățirea
muncii. Aplicarea metodelor descrise ar putea să aibă un efect favorabil în creșterea eficienței producției. Mai
mult, astfel de metode de management pot identifica și elimina problemele ce apar în astfel de procese.
Cuvinte cheie: QSB, operații forestiere, activități critice, exploatarea lemnului.
48
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
Map of Stone Quarries and Gravei Pits
in Romania: Possibilities to Use the
Materials in Forest Road Construction
Iulian Mihai NENU
1.	Introduction
Natural aggregates can be divided in two
major categories: above or near ground surface
rock deposits that can be crushed, and deposits
of sand and gravei respectively (Fodor, 2011).
Although they are considered to be the most
abundant natural resources and even if they
are characterized as low-value resources, when
opening an extraction site, whether it is a stone
quarry or a gravei pit, several factors have to
be considered as follows: the quality of the
aggregates, the available quantity, the location
relative to the recipient, the environmental impact
and the existing legislation and regulations
(Knepper et al., 1995).
Natural aggregates, consisting of crushed
stone, sand and gravei, are the most abundant
natural resources on the planet (Bleischwith
and Bahn-Walkowiak, 2006). Nevertheless, they
cannot be considered as never-ending resources.
Consumption of natural aggregates has increased
significantly in the last century as it has been
related to the industrial development all over the
globe. Such resources are particularly used when
building houses, industrial facilities and public
spaces or to develop and maintain infrastructure
(***, 2011), consisting of railways, public
transportation and special use roads including
here forest, agriculture and industrial roads.
Romania is located in Central East Europe
and has a total surface of 237 500 km2 being
characterized by a highly complex geological
structure. According to Fodor (2011) most of
the territory is part of Alpine Orogen, covering
all of the major landscape forms such as young
mountains, hills, plateaus and plains. Such a
geological structure offers, beside solid fuel (coal),
iron ore and other minerals a great variety of
useful rocks (Table 1). The available deposits can
be divided in three large categories: magmatic
rocks, sedimentary rocks and metamorphic rocks.
Requirements of natural aggregates in many
industrial sectors have increased the number of
extraction sites that can be divided into two major
categories: quarries and gravei pits. In 2005-2006
there was a number of approximately 440 sites
in Romania (Bohmer et al., 2007), excavating a
total of 23 million tons of natural raw aggregates.
From these, gravei pits were used to extract
approximately 15.5 million of tons while the
rest of 6.5 million of tons were extracted from
quarries. Currently there are registered almost
1000 extraction sites (***, 2017).
Table 1
Types of rock deposits available in Romania. Source:
Fodor (2011)
Mechanical Proprieties
Rock type	p*104 [N/m3]	c [%]	^rc*101 [Mpa]	a sm [daNcm /cm2]	O c uf [g / cm2]
Andesite	2.30/	80/	700 /	3/100	0.02 /
	2.65	98	2500		0.4
Dacite	2.30/	88/	1300/	5.1/72	0.1 /0.3
	2.83	96	2000		
Granit	2.30/	92/	1200 /	30/65	0.2
	2.90	98	2800		
Granodiorite	2.30/	92 /	1200/	25/65	0.01 /
	2.90	95	2800		0.3
Basalt	2.50/	95/	2500 /	15/50	0.05 /
	3.2	97	3500		1.5
Diabase	2.50/	95/	2200 /	15/50	0.05 /
	3.7	97	3000		1.5
Hone	1.90/	88 /	400 /	40/90	0.1 / 0.5
	3.70	98	2500		
Limestone	1.4/	80 /	500 /	2.6/33	0.33/
	2.8	97	1500		0.57
Note: p - density, C - compaction rate, QrC - breaking strength in
dried state condition, O - strength to mechanical shock, Q r -
.	.	i ,sm n .	.	Uf
weanng resistance during tnction.
Paved forest roads are the most common option
in forest transportation systems. At the same
time, natural aggregates are commonly used as
construction materials on the entire life spân of
the forest roads (Bereziuc, 1981). Although it is
highly recommended to use the local materials
to build forest roads as a way to lower the
construction costs, the geological structure of
a given construction site will not always allow
such attempts. It is also more than likely for
given construction sites not to tind the necessary
quantities or the required qualities of the need
material. Furthermore, the local environmental
impact generated by the extraction of the needed
Revisia făduriloe • Anul 132 • 2017 • Nr. 1
49
natural aggregates cannot be neglected, due to the
fact that such activities may produce irreversible
landscape changes.
In forest road design and construction, it is
recommended to use quarry products when
building the wearing and base course (Bereziuc
et al., 2009). More precisely, hard or medium-
hard rocks such as the chopped stone (pavers,
blocks, curbs) or crushed stone in different sizes
or mixes of sizes (e.g. 40-63 mm) are to be used
in the construction of mentioned layers. At the
same time, the road design is often influenced by
some parameters as being specific to a given area.
Among them, are the climate as well as other
geographic parameters including the available
construction materials. Lack of given materials
into a specific area, as well as the need to use
adequate construction materials as a function
of local climate, topography and transportation
requirements often translates in the necessity
to procure such materials from other places.
Procurement costs depend to a great extent on
the sourcing location, local market prices and the
forecasted quantities and qualities. To manage and
plan their production, logistics and costs, road-
building practitioners need updated Information
including that related to the location of available
resources. To this end, interactive maps showing
the location, resource type and procurement
costs are particularly helpful because they enable
comparisons and best option analysis in the
procurement of raw materials. For instance, the
Romanian state forests are managed by the State
Forest Administration - RNP Romsilva. At the end
of 2014 they had in their administration a number
of 7,752 forest roads developed on 26,055 km out
of which about 9,068 km were not funcțional
(Vișan, 2017) needing specific repairing and
maintenance operations.
The goal of this paper was to develop a nation-
wide interactive map showing the available
resources such as the stone quarries and gravei
pits and to enable route and cost calculation
based on the routes taken into consideration in
the procurement activities.
2.	Materials and Methods
Tire aim of this study was to analyze and map
all of the available sources of raw materials that
could be used in road construction operations in
a nation-wide attempt. A first step was that of
developing a database containing the existing
stone quarries and gravei pits in Romania. Tire
developed database contains the name of the
extraction source, type of rock, county and the
name of company which owns the extraction
license. Based on a satellite imagery analysis,
the GPS coordinates of the extraction sources
were obtained. Then, a map was developed using
Google Maps ® - an open source platform - that
enables the analysis as well as online publishing
of maps. Different colors and layers were built
and used to represent the stone quarries as
a function of rock deposits identified in the
previous step. For those users interested in a
particular type of raw material, the application
enables the activation and deactivation of
layers. The developed map enables routing and
distance calculation functions that can be used to
determine the transportation distance between a
given source and a forest road construction site.
The map can be either used online or downloaded
as a printable portable document format (.PDF)
or as a .KML format that enables its use in more
complex software for further analysis.
This paper concludes by a case study that
demonstrates the functionality of the developed
map. By choosing an existing location of a forest
road, the distances from all nearby stone quarries
were determined.
3.	Results
Quarry products are obtained by dislocation
and processing of massive rock located near
or above the ground surface (Fodor, 2011). Tire
products resulted after the processing operations
have sharp edges and rough surfaces, generating
internai friction between particles, making them
suitable for the construction of a forest road.
The locations of the stone quarries were related
to the geo-morphological structure of Romania.
Table 2 shows the number of stone quarries per
county for each type of hard rock suitable for
the development and maintenance of forest road
infrastructure.
Tire most important stone quarries in Romania
are located near the Carpathian Mountains as well
as in the Dobrogea area (Southeastern Romania),
where it can be found the oldest mountainous
formation in the country. A sample of the map
50
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
Table 2
Number of quarry stone extraction licenses
available in Romania. Source: NARM (2017)
County	A	D	G	GD	B	DB	H	L	T
Alba	3	1	-	-	-	-	1	-	5
Arad	1	-	-	-	1	3	-	1	6
Argeș	-	-	-	-	-	-	-	2	2
Bihor	-	-	-	1	-	-	4	4	9
Bistrița- Năsăud	3	3	-	-	-	-	1	-	7
Brașov	-	-	-	-	2	-	1	-	3
Buzău	-	-	-	-	-	-	-	1	1
Caraș- Severin	1	1	2	-	-	-	-	2	6
Cluj	-	2	-	-	-	-	-	4	6
Constanța	-	-	-	-	-	-	-	9	9
Covasna	2	-	-	-	-	-	-	-	2
Gorj	-	-	3	-	-	-	-	-	3
Harghita	11	-	-	-	-	-	-	-	11
Hunedoara	1	-	-	-	-	-	-	-	1
Maramureș	11	-	-	-	-	-	-	2	13
Mehedinți	-	-	1	-	-	-	-	-	1
Mureș	1	-	-	-	-	-	-	-	1
Neamț	-	-	-	-	-	-	2	-	2
Prahova	-	-	-	-	-	-	1	-	1
Sălaj	-	-	-	-	-	-	-	3	3
Satu-Mare	1	-	-	-	-	-	-	-	1
Suceava	2	-	-	-	-	-	5	3	10
Timiș				-					0
Tulcea	-	-	2	1	-	2	-	5	10
Total	37	7	8	2	3	5	15	36	113
Note: A - Andesite, U - Diorilc, G - Granițe, GD -
Granodiorite, B - Basalt, DB - Diabase, H - Hone, L -
Limestone, T - Total
developed in Google Maps is shown in Figure 1,
giving an overview of the source locations. At the
moment, there were mapped 75 from the total of
113 identified stone quarries.
îndesite
Bajai't Quarry
Dacite Quarry	Granodiorite Quarry
Fig. 1. Map of stone quarries
Gravei pits are large deposits of gravei and
sand, usually located in riverbeds, near rivers
or into lakes. Tire main characteristics of the
gravei pit products are the round shapes, smooth
surfaces and absence of sharper edges.
In relation to the construction and maintenance
of forest road infrastructure, gravei pit products
are used for concrete manufacturing, subgrade
and in the case of low volume traffic roads and,
in some cases, even for base course and wearing
course if other materials are not available. Their
rounded edges and smooth surfaces often result
in a lack of friction and cohesion between the
particles following the compaction process
of the roads, which will subsequently lead to
deformations of the road surface.
Due to the Romanian geological characteristics
and to a rich hydrological network, gravei pits can
be found all across the country in a higher number
compared to stone quarries. Table 3 shows, for
each county, the number of licenses released
for gravei and sand extraction. Such resources
are often located near the cities where there is
a constant need of gravei or similar products.
Another characteristic of such extraction sites is
that they often change their location as the pits
are depleted. From this point of view, keeping
records on an interactive map becomes even
more important.
In what concerns the utility of the developed
Table 3
Gravei Pits. Source: NARM (2017)
County	No of GP	County	No of GP
Alba	49	Harghita	12
Arad	17	Hunedoara	25
Argeș	27	Ialomița	2
Bacău	23	Iași	15
Bihor	25	Ilfov	2
Bistrița-Năsăud	13	Maramureș	45
Botoșani	14	Mehedinți	15
Brașov	20	Mureș	28
Buzău	21	Neamț	28
Călărași	1	Olt	24
Caraș-Severin	5	Prahova	37
Cluj	26	Sălaj	16
Constanța	7	Satu-Mare	16
Covasna	5	Sibiu	21
Dâmbovița	34	Suceava	38
Dolj	8	Teleorman	2
Galați	9	Timiș	19
Giurgiu	22	Vâlcea	23
Gorj	26	Vrancea	21
		Total	741
interactive map, a case study was designed to
demonstrate its capabilities and functionalities.
Figure 2 presents a simulation of distance
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
51
calculation for a specific point, marked by the
user on the map and considered as being a con-
struction site. For convenience, a forest road loca-
ted near Zărnești city (Brașov County) was taken
into consideration. As potențial supply sources, 3
of the closest raw material extraction sites were
considered for routing analysis as follows: B -
Vad 1 (gravei and sand - 28 km), C - Mateiaș Sud
Quarry (limestone - 78 km) and D - Valea Stânii
(basalt - 96 km).
Fig. 3. A case study of sourcing and raw material
transport routing
Distances were calculated using the public
road network up to the center of Zărnești city.
From there, all of the 3 supply routes merged into
a common road segment (route) of 23 km up to
the construction site. Although the closest source
is the gravei pit (B), such materials were not
considered as a viable solution for cover layers.
A comparison was carried out by considering
the two closest quarries (Table 4), namely Mateiaș
Sud Quarry (C) and Valea Stânii Quarry (D). Tire
analysis was done to evaluate the number of loads
needed to cover a given quantity of material, as
Table 4:
Analysis of scenarios. Sourcing of raw material
Location	Valea Stânii (B)	Mateiaș Sud (C)
Distance (km)	96	78
Rock type	Basalt	Limestone
Material Density (t/m3)	2.85	2.10
Required supply (m3)	1000	1000
Truck capacity (t)	24	
Truck load (m3)	8.42	11.43
No of required loads	119	88
Kilometers covered*	11400	6825
well as the number of kilometers to be covered
in the transportation between the source of
origin and the construction site. To this end, the
average rock density, a 24t truck and the volume
of 1000 m3 of crushed rock were considered as
parameters.
In order to enhance the functionalities given
by the map, one can use the density for each
type of rock as well as reference trucks used for
transportation to derive and estimate the fuel
consumption and the costs related to material
procurement. Also, the fuel consumption may be
further used to estimate the direct energy inputs
and environmental burdens associated with raw
material procurement for construction of forest
roads. In order to be able to obtain accurate results,
elevation data of each produced track should be
analyzed also because it is influencing the fuel
consumption, therefore the best provisioning
routes.
In the analyzed scenarios, the number of
covered kilometers was lower in the second option
both, due to the material density and distance. On
the other hand, this option needs transportation
of material over the Carpathian Mountains a
fact that could be negatively reflected into the
costs as an effect of the route topography, even
if the distance is shorter. However, this study was
designed only to give a tool for material routing
and distance calculation. As mentioned before,
such data can be exported and the best options
could be explored based on detailed analyses
using externai software.
4.	Conclusions
Distance from the source of raw materials
plays a key role in the procurement of materials
needed into the forest road construction activities.
Furthermore, the density of procured materials
affects the procurement activities due to the fact
that public transport limits the weight of trucks
to 40t including here the transported load. As a
large volume of natural aggregates are used for
each forest road project, each technical detail
could play an important role in establishing the
best provisioning source.
An interactive map with the stone quarries and
gravei pits as specific to Romania could help and
guide practitioners in the procurement process
of natural aggregates. Being an open source
(and public) map, it could be updated to cope
52
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
with the dynamics of some of the procurement
sources, enabling this way a reliable support for
practitioners.
Tire developed map was focused more on the
existing stone quarries and less on the gravei
pits. However, all of the existing gravei pits
were identified and the contact information was
included into the database.
Furthermore, the methodology proposed in this
paper could be developed further by integration
into a web portal. Such an attempt could result
in the provision of more details on the sourcing
and procurement of raw materials as well as a
more detailed map including those routes able to
provide significant savings in terms of time, fuel
and money.
References_
B e r e z i u c, R., 1981: Forest Roads [in Romanian],
Bucharest, 284 p.
B e r e z i u c, R., C i o b a n u, V., A 1 e x a n d r u, V.,
I g n e a, G., 2009: Elements supporting the development
cf the forest road design normative [in Romanian],
Transilvania University Press, Brașov, pp. 236-237.
B 6 h m e r, S., M o s e r, G., N e u b a u e r, C.,
Peltoniemi, M., S c h a c h e r m a y e r, E.,
T e s a r, M., W a 11 e r, B., W in t e r, B., 2007: Aggregates
case study. Final report referring to contract n° 150787-
2007 FI SC-AT, Aggregates case study - data gathering,
2007, 17 p.
Bleischwitz, R., Bahn-Walkowiak, B.,
2006: Sustainable Development in the European
aggregates industry: a case for sectoral strategies, 2006:
Acknowledgements
The author would like to thank the Romanian
National Agency of Natural Resources for
the support given and their guidance in the
procurement of data needed to build the database
and the map. Also, the author would like to
thank Prof.dr.eng. Stelian Alexandru Borz for his
advice and suggestions related to this paper, as
well as to the Department of Forest Engineering,
Forest Management Planning and Terrestrial
Measurements, Faculty of Silviculture and
Forest Engineering, Transilvania University of
Brașov for support and logistics needed in the
development of this study. This paper is also
supported by the PhD School of the Transilvania
University of Brașov.
Berlin Conference on the Human Dimensions of Global
Environment Change, p. 5.
F o d o r, D., 2011: Gravei Pits and Stone Quarries [in
Romanian], AGIR Publishing House, Bucharest, pp.
15-45.
K n e p p e r, D., L a n g e r, W., M i 11 e r, S., 1995: A
survey cf natural aggregate properties and characteristics
important in remote sensing and airborne geophysics.
Nonrenewable Resources Journal 4 (1), pp. 99-120.
V i ș a n, J., 2017: IT decision-making system for the
management and development cf the forest road network
[in Romanian], PhD Thesis, Brașov, pp. 22-23.
*** R e p o r t prepared for Sustainable Aggregates
Resource Management in SARMa Project 2011. ww.
sarmaprcject.eu
*** Agenția Națională pentru Resurse Minerale
[NARM], www.narm.ro, Accessed July 2017.
Eng. lulian-Mihai NENU
Faculty of Silviculture and Forest Engineering, Department of Forest Engineering, Forest Management
Planning and Terrestrial Measurements, Transilvania University of Brașov
iulian.nenu@yahoo.com
Map of Stone Quarries and Gravei Pits in Romania: Possibilities to Use the Materials in Forest
Road Construction
Abstract
As products of stone quarries or gravei pits, natural aggregates such as the crushed stone and gravei are essential
components in the construction of forest roads. Nevertheless, the road system choice is influenced by the types of
local or nearby existing material. At the same time, both in terms of economics and labor the road systems have a
significant share in the construction of a forest road and the choice of material sources should be done carefully.
This study aimed to identify, classify and map all of the Romanian stone quarries and gravei pits to provide a
spațial database containing the existing sources of supply for the development, maintenance and rehabilitation of
the forest road infrastructure in Romania. The developed database allows the analysis, in a sustainable approach,
Revisia pădurilor • Anul 132 • 2017 • Nr. 1
53
of technical and economic, social and ecological drivers, by offering the possibility of mnning various scenarios
to provide comparative resnlts between the effects of extracting natural aggregates on site or to source them from
quarries or gravei pits existing nearby.
Keywords: forest roads, spațial database, natural aggregates, quarry, gravei pit.
Hartă interactivă a carierelor de piatră și a balastierelor din România: Posibilități de utilizare a
materialelor în construcția de drumuri forestiere
Rezumat
Agregatele naturale, cum ar fi piatra spartă și balastul, sunt materiale esențiale în construirea de drumuri
forestiere. Cu toate acestea, în multe cazuri, alegerea sistemelor rutiere este influențată de tipurile de materiale
existente la nivel local sau în apropiere. în același timp, sistemele rutiere au o pondere semnificativă în construcția
unui drum forestier în ceea ce privește economia și forța de muncă, iar alegerea surselor de materiale ar trebui
făcută cu atenție. Acest studiu a urmărit identificarea, clasificarea și cartografierea tuturor carierelor de piatră
și a balastierelor din România pentru a furniza o bază de date spațiale care să conțină sursele de aprovizionare
existente pentru dezvoltarea, întreținerea și reabilitarea infrastructurii rutiere forestiere din România. Baza de
date dezvoltată permite analiza, într-o abordare sustenabilă, a factorilor tehnici și economici, sociali și ecologici,
prin oferirea posibilității de a analiza diverse scenarii pentru a furniza rezultate comparative între efectele
extragerii agregatelor naturale locale și cele specifice extragerii din cariere sau balastiere existente în apropiere.
Cuvinte cheie: drumuri forestiere, bază de date spațială, agregate naturale, carieră de piatră,
balastieră
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Revisla pădurilor • Anul 132 • 2017 • Nr. 1