• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.3
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• pp.163-173
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• 2011

This paper, as a case study on the evaluation of nationwide-unit forest functions, targeting the entire Gyeongsangnam-do region, examined the integration measures for the evaluation of national, public and private forest functions, as well as GIS data problems and GIS data building methods. Also, the distribution and characteristics of Gyeongsangnam-do's forest functions were examined. First, as integration measures for forest function evaluation, evaluation unit was proposed as watershed unit, and GIS techniques were proposed to correct some patterns of errors shown in the watershed maps. Also, of GIS data used for forest function evaluation, maps of locations of saw mills to be revised, expressway interchange location maps, and population distribution maps were built nationwide. Based on watershed units, the forest functions of 20 cities and counties in Gyeongsangnam-do were evaluated, revealing that wood production function and forest recreation function potentials, high-ranking was high distributed throughout the site, while most functions potentials, low-ranking was low distributed. In forest function maps with the application of priority by city and gun, the area size was ranked in the order of forest recreation, timber production, natural conservation, water yield, living environment conservation, and prevention of natural disaster. Case analysis results for large areas can be used in evaluating nationwide forest functions.

• Journal of Korean Society of Forest Science
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• v.90 no.2
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• pp.176-183
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• 2001

Loblolly pine (Pinus taeda L.) is the most economically important timber producing species in the southern United States. Much attention has been given to predicting diameter distributions for the solution of multiple-product yield estimates. The three-parameter Weibull diameter distribution yield prediction systems were developed for loblolly pine plantations. A parameter recovery procedure for the Weibull distribution function based on four percentile equations was applied to develop diameter distribution yield prediction models. Four percentiles (0th, 25th, 50th, 95th) of the cumulative diameter distribution were predicted as a function of quadratic mean diameter. Individual tree height prediction equations were developed for the calculation of yields by diameter class. By using individual tree content prediction equations, expected yield by diameter class can be computed. To reduce rounding-off errors, the Weibull cumulative upper bound limit difference procedure applied in this study shows slightly better results compared with upper and lower bound procedure applied in the past studies. To evaluate this system, the predicted diameter distributions were tested against the observed diameter distributions using the Kolmogorov-Smirnov two sample test at the ${\alpha}$=0.05 level to check if any significant differences existed. Statistically, no significant differences were detected based on the data from 516 evaluation data sets. This diameter distribution yield prediction system will be useful in loblolly pine stand structure modeling, in updating forest inventories, and in evaluating investment opportunities.

• Journal of Korean Society of Forest Science
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• v.84 no.4
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• pp.437-446
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• 1995

This study was carried out to estimate the Korean Pine stand structure such as coefficient of variation of mean DBH, number of trees and volume per ha by Weibull distribution for each age class from I to V, based on photo measurement and timber cursing in Kangwon National University Experimental Forests. The results were summarized as follows: 1) Coefficient of variation of mean DBH for each age class from I to V, which was obtained by converting DBH estimated from crown diameter by photo measurement into quadratic mean DBH, was estimated as 28.88%, 24.13%, 23.29%, 20.27%, and 18.79%, respectively. 2) Number of trees per ha of each age class by Weibull distribution was obtained as 2875, 2100, 1875, 800, and 325, respectively. 3) Volume per ha of each age class was estimated as $22.9m^3$, $66.8m^3$, $101.3m^3$, $209.6m^3$, and $266.8m^3$, respectively. 4) Therefore, aerial photographs will be helpful to estimate the stand structure effectively.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.115-121
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• 2016

This study was conducted to provide the basic policy information for establishing efficient forest-road networks. Synthetic forest-road networks that consist of main and spur roads and forest-road networks with only main road (hereafter called "main-road network") were planned for the five forest-road experimental districts of Korea Forest Service in this study. Road density of the synthetic forest-road networks was calculated and compared with the road density of the main-road networks. The results showed that the optimum road density of the synthetic forest-road networks was 10.1~15.9 m/ha, and the road density of the main-road networks was 8.4~12.4 m/ha. The construction cost of the synthetic forest-road networks was estimated about 1~8% lower than the main-road networks, while the road density was 20~30% greater than the main-road networks. As timber volume and hauling cost increased, the optimum road density of the synthetic forest-road networks increased, within which the road density of highstandard main road rapidly increased. On the other hand, the spur road density increased with slope gradient.

• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.490-502
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• 2014

This study investigates the cultivation processes of major nuts and fruits such as Ginkgo biloba L., Vitis coignetiae, Actinidia arguta Planch, Rubus coreanus Miq., and Rubus crataegifolius and analyzes standard income in order to provide foundational data necessary to make reasonable policies related with the criteria of compensating the loss of forest products or diagnosis of forestry management. According to the research results, the types of cultivation by items can be largely divided into open field culture and mountainous culture. Regarding the average annual income per unit area (3.3) by items, the open field culture of Ginkgo biloba L. was 1,060 Won, mountainous culture of Ginkgo biloba L. was 618 Won, open field culture of Vitis coignetiae was 5,891 Won, mountainous culture of Actinidia arguta Planch was 8,113 Won, open field culture of Rubus coreanus Miq. was 14,701 Won, and open field culture of Rubus crataegifolius was 17,482 Won or so; thus, the average annual income of Rubus coreanus Miq. and Rubus crataegifolius was very higher than that of the other items. In particular, because the production of Rubus crataegifolius starts two years after the planting and they rely on family labor mainly for the cultivation, the expenses for employment and labor were analyzed to be low. In addition, the analysis shows that at most of the nuts and fruits cultivation, initial investment costs for facilities or seedlings occupy a great part as about 30% averagely out of the management cost, so it is thought that the government should provide proper support to vitalize the cultivation.

• Journal of Korean Society of Forest Science
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• v.102 no.4
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• pp.484-490
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• 2013

This study was conducted to develop a simulation model for estimating the amount of such products as round wood, dimension lumber and the residual wood biomass produced by processing the individual trees of Larix kaempferi. In the model, the stem volume is assessed using the taper equations of the species to estimate the stem forms. Then, the model simulates the conversion processes of logs to round wood or lumber and assesses the maximum amount of the wood products by the lumber dimensions or round wood size. Also the model provides information on the amount of residuals for kerf and slabs produced on the conversion processes for sawn timber or round wood. According to the results of an application of the model to a L. kaempferi process, the trees greater than 12 cm of DBH can be converted to logs for lumber or round wood production. For the trees, of which DBH is available for log conversion, the maximum amount of final products by dimensions were analyzed. In this analysis, production of the bigger dimension lumber was assumed to be preferred to that of the smaller or round wood. This model can be used for assesment of forest economic value through estimation of merchantable volume for the trees, and assessment of mill residues which has the potential to provide significant amount of feedstock for bioenergy production as well.

• Journal of Korean Society of Forest Science
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• v.105 no.3
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• pp.342-350
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• 2016

This study aims to make the stand density management diagram which is very useful for establishing systematic management plan and obtaining management goal in Pinus densiflora forest. To estimate 5 models mainly composed of stand density management diagram, we used total of 1,886 sample plots having more than 75% of the total basal area of the pine trees in each stand. To test the goodness of fit, $X^2$ was computed with a significance level of 5%, and the acceptable error range as 20%. Also standard deviation of the model was $34.59m^3{\cdot}ha^{-1}$, minimum acceptable error range was 16.59% and coefficient of variation was 22.11%. If we use the stand density management diagram, it would be useful to establish the timber yield and thinning plan understanding the pathway of stand density management.

• Korean Journal of Plant Resources
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• v.13 no.1
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• pp.1-10
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• 2000

Pecan is deciduous tree and belongs to the Julandaceae family. Pecan is an economically important as a nut and timber crop. Heterozygosity is expected to be high for typically cross-pollinated. Yet little is known about the nature of genetic variation within this species. In addition, the pedigree of many pecan cultivars remains unknown or is questionable. In this study, the phylogenetic relationships between 22 pecan cultivars and its analyzed by RAPD (randomly amplified polymorphic DNA). PCR Amplification used 40 randomly selected oligoes as primers. Based on their genetic similarities derived from the RAPD data, the 22 pecan cultivars were classified into different five groups in agarose gel. The 22 pecan cultivars were classified into five sectional groups by UPGMA clustering analysis, too. C. flacra and Black walnut showed the 0.9 of similarity index and Farley, Pawnee showed the 0.85 of similarity index. The 22 pecan cultivars were classified into different five groups by analysis of the 4% polyacrylamide gel fraction. (Group I : 1, 2, 3, 4, 13, 16, 17, 20, 21 Group II : 14,18 GroupIII : 6,12 GroupIV : 5, 11, 15, 19, 22 CroupV : 7, 8, 9, 10) Group V show the 1.0 of similarity index and Farley, Sturya, Clarke, Pawnee show the 0.98 of similarity index and Kiowa, Schley show the 0.92 of similarity index. Results from this study indicated that RAPD can be used to establish the genetic relationships among the 22 pecan cultivars. Similarity coefficients generally agreed with what would be predicted in cultivars with known pedigrees, and we could accurately construct relationships among cultivars. In addition, we have shown that RAPD provides useful information on the origin of unknown cultivars.

• Journal of the Korean Wood Science and Technology
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• v.13 no.2
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• pp.35-44
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• 1985

The purposes of this study were, first, to investigate retention levels of toxic elements and oxide individual plies for each panel and, second, to examine disproportioning of individual toxic elements Thirty five water gum plywood panels were treated with a copper-chromium-arsenic preservative (CCA) by the soaking process as the treament time were applied. Such individual plies at a distance of 2.5cm, 7.5cm from the edge were assayed for CuO, $CrO_3$, and $As_2O_5$ on the basis of copper, chromium and arsenic content by Atomic Absorption Spectrophotometry. In these experiments, 12mm thickness plywood panels made of water gum, which were selling, were selected for the preservative treatment. Treating solutions were prepared for 10%, dilute solution of copper-chromium-arsenic preservative and then 1, 3, 6, 12 and 24 hours soaking trements in CCA preservative were applied. The results obtained are as follows: 1. The retention of total oxide in the face and back plies (1+7) retained more than the retention of total oxide in the other plies. The total oxide retention for the individual plies except the face and back plies (1+7) was showed in the following orders; cross plies (3+5), cross plies (2+6), core ply (4). 2. The retentions of total oxide increased as the increase of treatment time. The CCA treated plywood retained high levels of total oxide retention in the face and back plies (1+7). 3. All the retentions in the face and back plies (1+7) is over 5Kg/$m^3$, New Zealand Timber Preservation Standards Specification, and after 6 hours, the retentions in the cross plies (3+5) is over 4. The relative penetration of copper, chromium, and arsenic were not affected by the treatment time. The proportion of arsenic decreased in relation to both copper and chromium and the proportion of copper increased in relation to both chromium and arsenic. 5. A disproportioning of copper, chromium occurred with longer distance from edge, and with longer distance from edge the leachability resistance of CCA treated specimens decreased. After 6 hours (soaking time), the proportion of active elements at a distance of 2.5cm from the edge was consistent. And after 24 hours-soaking, the proportion of active elements at a distance of 7.5cm from the edge was consistent.

• Journal of the Korean Wood Science and Technology
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• v.48 no.2
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• pp.217-230
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• 2020

Global warming has increased interest in reducing greenhouse gas emissions. And a policy has effort to reduce energy consumption as a greenhouse gas reduction plan. In Korea, 25% of total energy is consumed in the building sector. In order to reduce energy consumption of buildings, it is possible to expand the utilization of wood as a structural material or thermal insulation materials with low thermal conductivity. It is also reported that when used as an interior finishing material, the energy consumption of the building is reduced by up to 7% by insulation performance. In this study, the heat transfer characteristics and the heat capacity were compared according to the three type of finishing materials(cement, paulownia coreana, medium density fiberboard) normally used as indoor finish materials. Through this study, most of the heat transfer volumes are transferred in the form of radiant heat, and the result was derived from the highest amount of energy and heat transfer in the use of paulownia coreana. When indoor finishing materials are used as wood, it is deemed that energy efficiency inside the building will be improved.