• Journal of the Korean Wood Science and Technology
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• v.47 no.2
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• pp.239-248
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• 2019

This research presents an improvement of the physical and mechanical properties of composite board (com-ply) made of Oriented Strand Board (OSB) coated with wood veneer of Pine (Pinus merkusii), Avocado (Persea Americana) and Mahogany (Swietenia mahogany). 1.5 mm thick veneers of those three wood types were adhered to the surface of OSB using two adhesive types: epoxy and isocyanate. The adhesive with the glue spread of $250g\;m^{-2}$ applied using single glue line was spread and then cold pressed with the pressure of $15kg\;cm^{-2}$ for 3 hours. The research result showed an improving dimension stability of com-ply, but not found on all parameters of physical property test. The moisture content seemed to be influenced by the com-ply type, yet not related to its thickness swelling, water absorption and linear expansion. The exception took place in the parallel linear expansion when immersed for 2 hours. The highest to the lowest increases of MOE and MOR were consecutively found on OSB coated with wood veneer of Pine, Mahogany and Avocado. However, the increases were statistically insignificant. The highest increasing screw hold power was found at the com-ply type AE (avocado veneer and epoxy adhesive) that was by 28%.

• Journal of Korean Society of Forest Science
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• v.101 no.4
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• pp.695-702
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• 2012

The chestnut management standard diagnostic table is developed and would be utilized in order that a manager raising chestnuts checks where the own level of management is and grasps current state of own for the purpose of planning aims and advancing toward a higher level. The developed 'Chestnut management standard diagnostic table' consisted of 3 first classified items, 19 second classified items and 2 product indicator items by the chestnut experts consultative meeting. A survey of 212 farmhouses in 4 major producing area was conducted. Except invalid survey of 53 farmers, 159 farmhouses interviewed were used in analysis. Total score was calculated with sum of each item's score. According to the survey results, average score is 68.0 and Buyeo received the highest score of 69.7 and Suncheon received the lowest score of 61.8 by regional groups. The higher the group in score, the better it is in output per hectare. But the property of 'the ratio of the best products in total products' does not show a statistical correlation. Generally the score of 'management-based evaluation indicator part' and 'management and sale capacity indicator part' in Suncheon was low because of many elderly people. In part of 'manufacturing technology indicator' as Environmentally-Friendly production is progressed in over 70% of four regions, when comes to a disease and insect pest control there are rarely farmhouses having a way of crop dusting.

• Journal of the Korean Wood Science and Technology
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• v.51 no.5
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• pp.334-344
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• 2023

Dregs from the sugar palm (Arenga pinnata) starch industry are considered a waste product of the agricultural industry and have not yet been optimally utilized. Therefore, this study aimed to manufacture particleboards from dregs using different amounts of adhesive and particle size ratios. Sugar palm dregs, which had been separated into fibers and powder/fine particles, were used as raw material for making particleboards. The fiber had an average length of 6.84 ± 3.23 cm, while the fine particles were of a size that passed through size 10 mesh and remained in size 60 mesh. Three ratios of fiber to fine particles (100:0, 75:25, and 50:50 wt%) with three different amounts of sucrose-citric acid adhesive (10, 15, and 20 wt%) were used in this study. Increasing the amount of fine particles and the resin content can improve the physical properties and the internal bond strength of boards made from sugar palm dregs. The fine particles possibly filled the gap between the fibers in the particleboard, while the fibers exhibited a high bending strength. As a result, a high-performance particleboard can be attained by combining the composition ratio of fiber/fine particles and resin content. In this study, particleboards made from fiber/fine particles (75:25 wt%) and adhesive content of 15 wt% and 20 wt% had the mechanical properties that met the requirements of Japanese Industrial Standard (JIS) A 5908 type 18. Sugar palm dregs have the potential to be used as raw materials to create value-added particleboards.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.3
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• pp.177-186
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• 2002

This experiment was conducted to examine possibility and suitability of forest by-product as a roughage source of deer. As a experimental diet, forest by-product silage(FPS) and commercial mixed ration(CMR) were prepared to compare dry matter intake, digestibility, nitrogen balance and feeding behavior in feeding trials with spotted deer. The digestibility of dry matter was higher(P<0.05) in CMR than in FPS. The digestibility of crude protein was higher in CMR than in FPS and there was significant difference(P＜0.05). CMR had more digestibility of crude fiber than FBS but the difference was not significant. Dry matter intake were similar in both diets. Digestible dry matter intake was higher in CMR than FPS, however, there was no significant difference between experimental diets. Nitrogen intake, urinary and digestible nitrogen were significantly higher(P<0.05) in CMR than FPS. The efficiency of nitorgen utilization was higher for FPS than for CMR. Feeding behavior were similar in FPS and CMR. Consequently. It would be expected that FPS that composed with various feed sources can be used as a good roughage source of deer. Because it has high digestibility, dry matter intake and internal availability of nitrogen.

• Journal of Korean Society of Forest Science
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• v.97 no.1
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• pp.45-52
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• 2008

The objectives of this study are to explain a supply plan of domestic softwood log by long-term prospect of MDF production to stably promote industry of MDF. For it, we developed the long supply function as Ordinary Least Squares Method. Between 2005 and 2050, it was estimated that quantity of domestic production of MDF increased from 1,653 thousand $m^3$ to 2,041 thousand $m^3$. In 2050, quantities of domestic softwood log used by raw materials to product MDF of 2,041 thousand $m^3$ were estimated to be used about 1,355 thousand $m^3$. Exampling Pinus rigida used presently by raw materials to product MDF, cutting area of it is estimated to be 10,828 ha per year. And larch is cutted about 9,160 ha per year. This study estimated annual softwood log cutting amount and total afforestation area at 2050 year by 3 scenarios which are 35%, 45% and 55% about use of domestic softwood log for MDF production. If we do a criterion of cutting area, we advantage to plant larch. But the species of trees are use and growth property. We think that the afforestation policy must be performed on the base of those to supply raw materials of MDF. Although government plans hardwood afforestation policy after cutting Pinus rigida, it needs to support and manage certainly afforestation area of softwoods to need to supply raw materials of MDF to stably promote industry of MDF.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.1
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• pp.65-73
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• 2013

FDB(Feature DataBase) attributes have been produced by using the resource data prior to the year 2002. Due to this reason, the attributes need to be updated to the up-to-date ones. In this regards, this study focuses on the way of finding areas whose attributes need to be updated. Forest and crop classes were chosen as target classes among FDB features. MODIS Landcover data and FDB are, first, compared to detect the changed forest and crop areas from 2001 to 2008. Then, vegetation vitality changes are analyzed using MODIS annual NDVI data. Based on the change detection and the vegetation vitality analysis, the index of area selection for updating FDB attributes is proposed in this study.

• Fire Science and Engineering
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• v.24 no.1
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• pp.103-110
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• 2010

Farming activity was the second cause of forest fire following the carelessness. In this study, 74 forest fires caused by farming activity and waste burning in 2009 was investigated for analyzing ignition patterns. The main cause to bring about forest fire was the farming waste burning as 25 cases, burning of farming waste matter after product and household waste burning were the second causes as 19 cases. Landcovers which transfer flame from ignition point to forest were fallow field graveyard, field fruit farm, field levee fallow field. The average distance between ignition point and forest sleeve was 19 m, and the maximum distance was 130 m. The probability of forest fire ignition was high in the 100 m buffer zone from the forest sleeve that is the prohibition rule of fire use for forest fire prevention at the forest fire season.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.1
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• pp.10-18
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• 2000

To improve the physical properties of OCC (Old Corrugated Container) fibers, we used the mechanical pre-treatment on the fibers before refining . The mechanical action in the Hobart mixer induced high shear and compression on the fibers, which resulted in changes of fiber internal structure, and microcompressions on the surface of the fibers. We evaluated the amount of mechanical treatment on the fibers by fiber curl index for convenience. Four different refining techniques were applied to the pre-treated fibers (valley beater, Kady mill, PFI mill, and Impact refining) to find the best combination of the pre-treatment and the refining methods. Conclusions were summarized as followed. 1. Mechanical pre-treatment in Hobart mixer for more than 1 hour caused the increase of curl index of OCC fibers, and increased breaking length, burst index, and tear index the handsheets more than 10 % in this experiment. 2. Kady mill and PFI mill refining were effective in keeping fiber length from shortening Kady mill and Valley beater refining straightened out the fiber curls, and reduced the curl index. 3. Valley beating reduced fiber length very fast and generated fines more than other refining methods. 4. To increase breaking length and burst strength while keeping tear strength , combination of mechanical pre-treatment and Valley beating were most effective.

• Journal of Korean Society of Forest Science
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• v.95 no.2
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• pp.203-208
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• 2006

This study compared the roundwood demand prediction accuracy of econometric and time-series models using Korean data. The roundwood was divided into softwood and hardwood by species. The econometric model of roundwood demand was specified with four explanatory variables; own price, substitute price, gross domestic product, dummy. The time-series model was specified with lagged endogenous variable. The dummy variable reflected the abrupt decrease in roundwood demand in the late 1990's in the case of softwood roundwood, and the boom of plywood export in the late 1970's in the case of hardwood roundwood. On the other hand, the prediction accuracy was estimated on the basis of Residual Mean Square Errors(RMSE). The results showed that the softwood roundwood demand prediction can be performed more accurately by econometric model than by time-series model. However, the hardwood roundwood demand prediction accuracy was similar in the case of using econometric and time-series model.

• Journal of Korean Society of Rural Planning
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• v.15 no.4
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• pp.135-146
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• 2009

Urban forest area in South Korea has been increased up to 20.8% of national land as of 2007 by the mergence of municipalities and counties. The rate of park and green tract among urban forest averages out to about 4% nationally but the Capital, Seoul, almost 105% level, not easy to split the two. Park and green has positive management system because of its infrastructure attribute and relevant security obligation standard while urban forest left alone with no such concerns. The most important reason of the negligence comes from institutional inertia although it is possible to be managed functionally by forest laws as like forests of park, landscape, wind and noise protection, and timber product. As a results, it reaches below than 92.64% of the national average level of the timber stockpile especially in the metropolitan areas and loses broad acres rapidly due to the easy conversion system to the urban land usage. Therefore, there must be required some alternative methodologies to conserve and foster it. The paper proposes the four urban forest management types and their control methods. The four types divide into conservation, foster, development, and reservation ones. Also it suggests the five furtherance tract types with the combination among the four earlier types, optionally having one of the six aim climaxes and recommends the standardization of operation design. The total green quantity index of urban forest also suggested by the weight method according to location and DBH class. The case study of the suggested model was executed on the Daejon Metropolitan area and its index calculated as 110.4% level compared with the acreage.