• Journal of the Korean Wood Science and Technology
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• v.24 no.1
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• pp.11-16
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• 1996

The purpose of this paper is to present a summary of assignment design values according to domestic softwood structural lumber grading rules. Allowable stresses for visually graded lumber were determined from basic data on small. clear specimens. The data corrected for variability such as natural defects and other factors. The procedure adopted by Japan was used for assigning allowable design values. Strength ratios in relation to each defect were taken from ASTM D 245-81. Korean pine(Pinus koraiensis S. et Z.), Korean red pine(Pinus densiflora S. et Z.), Japanese larch(Larix leptolepis Gordon) and Needle fir(Abies holophylla Max) were applied to this study. The calculated allowable stresses were same in Korean pine and Korean red pine. These values were highest in Japanese larch lowest in Needle fir. So, it is desirable for these species to be classified into different catagories Species Group. However, accurate comparison in design values on lumber grading rules among U.S., Japan and Korea was somewhat difficult. And full scale testing will be necessary for accurate determination of the correction factors to setting up design values.

• Journal of the Korean Wood Science and Technology
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• v.21 no.3
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• pp.22-29
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• 1993

나뭇잎으로부터 발생되는 저분자량 유기산을 이온크로마토그래피를 이용하여 분석하였다. 이 방법은 자연상태의 나뭇잎 (needle litter)을 유기용매의 추출 없이 그대로 이용할 수 있어서 사용하기에 편리하다. 본 논문에서는 이온 크로마토그래피의 사용방법과 침엽수잎(Pacific Silver Fir)의 부후정도에 따른 유기산의 종류와 농도의 변이를 간략하게 소개한다. 초기의 침엽수잎 여과액으로부터는 $C_2$에서 $C_4$까지의 아세트산(acetic acid), 프로피온산(propionic acid), 옥살산(oxalic acid) 그리고 포름산(formic acid) 등이 주종을 이루지만 부후정도가 커짐에 따라 방향핵을 가진 방향핵 유기산(aromatic organic acid)이 발생한다.

• Journal of Korean Society of Forest Science
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• v.108 no.2
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• pp.200-207
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• 2019

The aim of this study was to provide the basic information necessary to identify Korean fir (Abies holophylla), momi fir (A. firma), and Nikko fir (A. homolepis), and other fir trees planted in South Korea that are protected by law. Analysis of the morphological characteristics of the needles from each sample was investigated. The shape of the needle-leaf tip from A. holophylla was acute, whereas that from A. firma and A. homolepis was emarginate and that from the protected fir trees was obtuse. The number of stomata on the needles was not significantly different between A. holophylla and A. firma, and the number of stomata on the needles from A. homolepis and the protected fir trees were highly similar. In addition, the genetic differences among the Abies species were analyzed using the sequences of five chloroplast DNA regions-matK, atpF-atpH, rpoC2-rps2, rpoC1, and psbA-trnH.The atpF-atpH and psbA-trnH regions were useful for discriminating A. firma from the other species, but there were no differences among A. holophylla, A. homolepis, and the protected fir trees. The same chloroplast sequences were found in both A. holophylla and A. homolepis, which suggests that additional genetic studies might be necessary to identify the Abies species planted in both South Korea and Japan.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.2
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• pp.11-19
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• 2019

The study was done to analyze the records of planting time of Gwangneung needle firs referring to the historical literatures, the Annals of Joseon Dynasty(朝鮮王朝實錄), Seungjeongwonilgi(承政院日記: Journal of the Royal Secretariat). Bibyeonsadeungnok(備邊司謄錄: Records of the Bibyeonsa Defense Council, a government agency during the Joseon Dynasty), Ilseongnok(日省錄: Journal on Dynasty affairs of the kings in the 36th year of Youngjo to 1910) to lay the historical ground for needle firs in Gwangneung. The following results were derived from previous research, Report on Gwangneung Forest Ecosystem, and overlaid fir tree rings. The research findings are as follow. First, since the system of making the grave is the most conservative system, the planting during the Gwangneung construction would have been preceded by precedent. Second, the problem of cutting the tree in the late Joseon Dynasty became serious. It is published the Law of Muo In the 22nd year of Jeongjo, and then planted trees regularly in spring and autumn. Third, the Law of Muo was preserved for 31 years during the reign of King Gojong, and the type of specific tree, the number of trees, from the 22nd year until the 25th year of King Gojong, four years of fir trees were planted in Gwangneung, and Gwangneung was the only place where korean pine trees were planted. Fourth, it was possible to identify the age of the tree through fallen fir tree rings, and the period of planting fir trees growing in the existing mausoleum is judged to be the equivalent year of King Gojong's reign from the 10th year of King Cheoljong's reign.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.565-572
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• 2001

The spatial genetic structure of Needle fir(Abies holophylla Max.) seedlings on forest gap within a Needle fir forest at Mt. Odae in Korea was analyzed on the basis of ISSR(inter-simple sequence repeats) marker analysis. The gap size was $1,500m^2(50m{\times}30m)$, and we sampled 416 one- or two-year-old seedlings by 2m intervals. Some trees at the upper crown layer except Needle firs and all trees at the middle and lower crown layers were removed, and Needle firs at the upper crown layer showed very weak growth strength or to be withering to death. The results of spatial autocorrelation using 31 polymorphic ISSR markers revealed that it was genetically homogeneous within spatial distance of 15.6m and the randomness of genetic distribution was from 15.6m to 31.2m. The genetic patch size of seedlings in forest gap might be restricted by the density of mother trees, making allow for the average height of adult Needle firs, the seed dispersal area, and the average distance between adults. For the directionality of seedling distribution, we investigated the variography using 'genetic configuration' which was the value of configuration in Multidimensional Scaling by genetic distance. In directional variogram, the increment of spatial distance from East to West direction was inversely proportional to genetic homogeneity. We presumed that this anisotrophy of seedling distribution at this forest gap resulted from the directionality of seed dispersal rather than the difference of fecundity between mother trees or the microhabitat variation, taking the evenness of forest floor condition, a vast seed production and the random distribution of seedlings at the studied site into consideration.

• Journal of Bio-Environment Control
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• v.15 no.1
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• pp.100-106
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• 2006

A hypertonic solution of sorbitol was used to precondition Douglas-fir and Western hemlock plug seedlings to improve desiccation resistance. Seedlings were preconditioned by soaking their root balls in water, -0.75 or -1.50 MPa sorbitol solution for 22 hr, and then exposed to desiccation conditions for 8 days. During the desiccation period, a transpirational water loss was significantly reduced by the sorbitol preconditioning, with its effect positively depending on concentration. This preconditioning-induced reduction in water loss was mainly caused by the decline in needle stomatal conductance. Sorbitol-induced stomatal control was more closely associated with reduction in plant water potential, rather than increase in abscisic acid concentrations. After rehydration of stressed-plants, most of the preconditioned seedlings with sorbitol were survived, while only 35% of Douglas-fir and 28% of Western hemlock seedlings treated with water were alive. The post-growth was significantly greater in the preconditioned seedlings than only water-treated seedlings. These results suggested that the earlier stomatal control with sorbitol-facilitated preconditioning could play a role in improving desiccation resistance of evergreen woody plants at transplanting in the field where water supply is limited or dry conditions are prevailing.

• Journal of the Korean Wood Science and Technology
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• v.19 no.3
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• pp.72-76
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• 1991

The new preparative separation techneque of dihydroquercetin (2, 3-trans-dihdroxy-3, 3', 4', 5, 7-pentahydroxydihydroflavonol) was investigated by liquid chromatography. Also some typical coniferous wood bark were examined for the sources of dihydroquercetin. The good sources of dihydroquercetin were Douglas-fir[Pseudotsuga menziesii] bark and pitch pine [Pinus rigida] bark. There is no dependance the produced place and species dihyroquercetin which is separated by silica-gel column chromatography was taken with white needle-like crystals. This crystals were very stable in the humidity and on the light. It also can stored very long without derivatives.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.366-377
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• 2016

Water use efficiency (WUE) is considered as an important ecological indicator which may provide information on the process-structure relationships associated with energy-matter-information flows in ecosystem. The WUE at ecosystem-level can be defined as the ratio of gross primary productivity (GPP) to evapotranspiration (ET). In this study, KoFlux's long-term (2007-2015) eddy covariance measurements of $CO_2$ and water vapor fluxes were used to examine the WUE of needle fir plantation in Korea National Arboretum. Our objective is to ascertain the seasonality and inter-annual variability in WUE of this needle fir plantation so that the results may be assimilated into the development of a holistic ecological indicator for resilience assessment. Our results show that the WUE of needle fir plantation is characterized by a concave seasonal pattern with a minimum ($1.8-3.3g\;C{\cdot}(kg\;H_2O)^{-1}$) in August and a maximum ($5.1-11.4g\;C{\cdot}(kg\;H_2O)^{-1}$) in February. During the growing season (April to October), WUE was on average $3.5{\pm}0.3g\;C\;(kg\;H_2O)^{-1}$. During the dormant seasons (November to March), WUE showed more variations with a mean of $7.4{\pm}1.0g\;C{\cdot}(kg\;H_2O)^{-1}$. These values are in the upper ranges of WUE reported in the literature for coniferous forests in temperate zone. Although the growing season was defined as the period from April to October, the actual length of the growing season (GSL) varied each year and its variation explained 62% of the inter-annual variability of the growing season WUE. This is the first study to quantify long-term changes in ecosystem-level WUE in Korea and the results can be used to test models, remote-sensing algorithms and resilience of forest ecosystem.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.7
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• pp.106-111
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• 1989

A new EMG signal processing algorithm for SMUAP pattern classification is proposed. It checks the combination and regularity of ISI using a spike counter as a decision making routine, and performs SMUAP waveform alignment in frequency domain and selects spikes through FIR filtering. As a result, with the EMG signals recorded during 5 seconds at 10-50% MVC force level, the SMUAP ranged from five to nine units were classified and identification rate is greater than 55 percent using a concentric needle electrode. In the IBM PC/AT the processing time typically required 2 minutes.

• The Korean Journal of Ecology
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• v.12 no.3
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• pp.191-202
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• 1989

This study was carried out to investigate the relationship between soil mites(Acarina:Cryptostigmata) and vegetation in sampled area. From July 1984 to June 1985, samples were taken monthly from coniferous forests; a pinenut (Pinus koraiensis S. et Z.) forest (site C-1), a whitepine(Pinus strobus L.) forest (site C-2), a needle fir tree(Abies holophyla Max.) forest (site C-3), and three broad-leaved forests; site B-1, B-2, and B-3 in Cholanamdo province, southerm part of Korea. Vascular plants of 152 species belonging to 115 genera (53 families) were identified. The flora in the coniferous forests were more diverse than in the broad-leaved forest. Similarity coefficient to the flora was shown highly between the neighbouring sites. The oribatid species in the coniferous forests were more diverse than those in the broadleaved forests. The similarity index suggested that oribatid mites in those surveying sites could be divided into "coniferous forest type" and "broad-leaved forest type".d forest type".uot;.