• Journal of Korean Society of Forest Science
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• v.109 no.2
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• pp.145-156
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• 2020

In 2000 and 2018, phytosociological surveys were carried out in the forest vegetation of Mt. Yeompo, a representative isolated urban forest in Ulsan city. The trends of change in forest structure, composition, and spatial distribution were compared between years. Total percent coverage per 100 squaremeters of forest vegetation was similar, but natural vegetation showed a 9% increase. The importance of constituent species changed slightly. Specifically, Lindera erythrocarpa and Styrax japonicus showed very high growth rates of 835% and 269%, respectively. Species richness (S) and diversity (H') decreased by about 22% and 8%, respectively. Both S and H' showed slightly higher rates of decrease in artificial compared with natural vegetation. The constituent species life form spectrums were the same in 2000 and 2018 as 'MM-R5-D4-e'. The similarity (Jaccard coefficient) in the species composition of the forest vegetation was almost homogeneous at approximately 75%. The number of indicator species decreased from 16 species in 2000 to 7 species in 2018. This decrease was mostly due to a decline in herbaceous plants, such as Hemicryptophytes, Geophytes, and Therophytes, which are sensitive to disturbances. The spatial distribution of forest vegetation did not change significantly. The number of forest landscape elements (patches) increased by approximately 25% from 537 in 2000 to 721 in 2018, while the average size decreased by about 20% from 1.28 ha in 2000 to 1.03 ha in 2018.

• Journal of the Korean Wood Science and Technology
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• v.41 no.1
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• pp.42-50
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• 2013

Since 1990's, a plywood for flooring base has gotten customers' demand. Costs of raw material and production increased because of changed environment of industry. Tropical timber such as Red Meranti (Shorea acuminate) used for raw material of the floor has been depleting beside countries in South Eastern Asia changed species of afforestation. As a result, it gets hard to secure good quality of raw material for plywood. Moreover plywood price is increased suddenly after earthquake in Japan. Eucalyptus (Eucalyptus globulus) in china has been using for raw material as a countermeasure of changed environment of industry. In this study, possibility of using flooring consisted of Eucalyptus veneer as crossband layers was checked by deflection experiments. Flooring consisted of Red Meranti was used for comparison. Two factors which impact on deflection are a type of density gradient and density difference between Long-grain veneer and Short-grain veneer. Red Meranti samples are M type of density gradient on the other hand Eucalyptus samples are W type of density gradient. The more samples have high density difference, the more deformation was checked. A sample which has big density difference between core and cross bands layer warp more also deform. Flooring was deformed smaller than plywood and samples which have big density difference was deformed more.

• Food Science and Preservation
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• v.17 no.1
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• pp.139-144
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• 2010

This study was carried out to investigate potential applications of the extract of Castanopsis cuspidata var. sieboldii $N_{AKAI}$ nut as a functional food ingredient. The pH and $^{\circ}Brix$ of nut were 6.43 and 3.17, respectively. L, a and b values as Hunter's color were 83.07, 1.49 and 10.48, respectively. Total content of monosaccharide was 54.26 mg% and organic acids were composed of oxalic acid 495.37 mg%, formic acid 200.03 mg%, malic acid 93.65 mg%, citric acid 27.80 mg%, and succinic acid 16.61 mg%. Total phenolic contents in various solvent extracts were as follows: water 27.69 mg%, 75% ethanol 16.50 mg%, ethyl acetate 16.50 mg%, and methanol 10.30 mg%. The antioxidant activity ($SC_{50},\;{\mu}g/mL$) of the nut extracts by various solvents was in the order of ethyl acetate 74.88 > methanol 155.00 > n-hexane 213.33 > ethanol 249.33 > butanol 274.78 > chloroform 314.67 > 75% ethanol 848.33 > water extracts 869.67. The results indicated that the extract of C. cuspidata nut contained a potential food ingredient.

• Journal of Applied Biological Chemistry
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• v.63 no.2
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• pp.161-168
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• 2020

It is known that different plant species have ability to deposit different amounts of particulate matter (PM) on their leaves and plants can absorb heavy metals in PM through their leaves. Heavy metals in PM can have toxic effect on human body and plants. Therefore, PM on different roadside trees at Chungbuk national University including box tree (Buxus koreana), yew (Taxus cuspidate), royal azalea (Rhododendron yedoense), and retusa fringetree (Chionanthus retusa) was quantified based on particle size (PM_>10 and PM_2.5-10). The metal concentration in PM accumulated on leaves was analyzed using inductively coupled plasma-mass spectroscopy. In this study, the mass of PM_>10 deposited on the surface of the tree leaves ranged from 6.11 to 32.7 ㎍/㎠, while the mass of PM_2.5-10 ranged from 0 to 14.8 ㎍/㎠. The royal azaleas with grooves and hair on the leaf surface retained PM particles for longer time, while the yews and box trees with wax on leaf surfaces accumulated more PM. The PM contained elements in crustal material such as Al, Ca, Mg, and Fe and heavy metals including Cu, Pb and Zn. The concentration of elements in crustal material was higher in the coarser size, while heavy metal concentration was relatively higher in the finer size fraction. The Mn, Cd, Cu, Ni, Pb, and Zn concentrations of leaves and PM_2.5-10 were significantly correlated indicating that PM was taken up through tree leaves.

• Journal of the Korean Wood Science and Technology
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• v.27 no.3
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• pp.39-50
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• 1999

This research was carried out to investigate the development of fire-retardancy treatment technology and performance evaluation of fire-retardant treated plywoods. Radiata pine, keruing, dillenia, calophyllum and terminalia veneers were treated by normal(conventional) pressure soak(NPS) and vacuum-pressure-soak(VPS) using 20% water solution of diammonium phosphate. Then, 4.8mm thick, 3ply plywoods were fabricated with combination of fire-retardant treated, untreated or water-immersion types and several composition types of radiata pine and keruing veneers, i,e. the uniform and the mixed types in species composition, and the homogenious and the alternate layer types in veneer treatment. In composed species, the retention and the treatment effects of fire-retardant chemicals III radiata pine was still greater than those of keruing. The effect of VPS treatment was larger than that of NPS treatment, however, adhesive bonding strength and bending strength of plywoods treated by these two methods were not necessarily lowered, compared to those of untreated plywood. And also, fire endurance performance of the urea melamine resin-bonded plywood was greater than that of the phenol resin-bonded plywood. In result, the appropriate combination in veneer species and layer as well as alternate fire-retardant treatments would be more efficiently available in service.

• Journal of Korean Society of Forest Science
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• v.98 no.3
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• pp.247-254
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• 2009

In this study, linear programming was applied to a case study in Gwangreung Experimental Forest of Korea Forest Research Institute investigating the effect of the desired future conditions on forest management. Considering the social, economic and ecological demands of people from the forest, the forest functions were classified into four including natural conservation, timber production, water yield and scenic conservation. The forest land areas were divided into four-types of forest functional zones and forest management prescriptions including the desired future conditions by the forest function type were established. The Model II linear programming was used in optimizing the forest management planning. The model includes management policies, as the constraints, for non-declining yield, allowable cutting area, allowable % age class distribution and allowable % species allocation as well as the land and other accounting regimes. Maximization of timber production was used the objective function. Based on the Model II formulations, the effects of the desired future conditions by the forest function type on forest management planning were investigated in terms of timber production, net present value and stand structures over time.

• Journal of Korean Society of Forest Science
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• v.95 no.6
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• pp.729-734
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• 2006

This paper aimed to suggest decision-making method for forest management planning using integer programming. Thus, the study examined 85 stands consisting of Korean pine, Japanese larch and oak stands-all of which were at the most suitable time for tending, selection thinning, commercial thinning and final cutting-in the experimental forest of Kangwon National University. The forest management model comprised one objective function, maximizing harvest volume in each stand according to tree species and the kinds of practices, and seven constraints: frequency and stands of practices, minimum and maximum yields, even yields, maximum production, and decision-making varialbes. Besides, the entire period intended by the study was 10 years, divided into 5 management periods. In conclusion, the forest management planning model using integer programming proved that among 85 stands, forest practices were conducted over 68 stands (202.8 ha), producing the total harveted volume of $20,000m^3$, while the rest was reserved. This case study could help make decisions on whether and when the forest practices and harvests could be done in a specific condition.

• Korean Journal of Ecology and Environment
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• v.40 no.3
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• pp.468-480
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• 2007

The urbanization is altering the hydrology, water quality, channel form of waterway and changing the composition of biological communities in the aquatic ecosystem. Recently, towns grew bigger by the drift of large numbers of people and the medium and small leather and dyeing industries around the Pocheon and Youngpyeong streams. The discharges of sewage were increased by them. The UII (urban intensity index) was 85 (st. P-3) and 91 (st. P-6) in the Pocheon stream and about 20 in the Youngpyeong stream. A total 141 taxa of epilithic diatoms which were composed of 2 order, 8 family, 30 genera. Dominant species were Navicula saprophila, N. subminuscula, Nitzschia palea, Gomphonema pseudoaugur in the Pocheon stream and Achnanthes alteragracillima, A. convergens, A. minutissima, N. minima, N. fonticola, N. frustulum and Cymbella minuta var. silesiaca in the Youngpyeong stream. It Showed the different composition of dominant species by the urbanization near two streams. In the relationships between UII and environmental factors such as EC, BOD, COD, TN, TP and DAIpo, UII showed the high relations $(r^2>0.8)$. It was the difference of organic pollution according to urbanization. It therefore, was higher the relative abundance and more the numbers of saprophilous taxa in the Pocheon stream than the Youngpyeong stream. The water quality of two streams by biological indicators(DAIpo) was polysaprobic state(st. P-3, P-4, P-5) in the Pocheon stream and was oligosaprobic (Y-1), mesosaprobic (Y-2, 3) and polysaprobic state (Y-4) in the Youngpyeong stream during the investigation periods.

• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.51-65
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• 2024

Phyto-sociological methods were used in this study to assess the vegetation structure of a forest stand at Mt. Goehwa in Sejong-Si with the aim of providing vegetation information for urban forest utilization and management plans. The actual forest vegetation was classified into two types of community groups (Quercus serrata-Lindera obtusiloba and Coreopsis lanceolata community groups) at the highest hierarchical level. The Q. serrata-L. obtusiloba community group was classified into six units, which included artificial forest and natural forest vegetation. Artificial forests were classified into three communities (Pinus rigida, Castanea crenata, and Robinia pseudoacacia), whereas natural forests were classified into three communities (Quercus variabilis, Quercus acutissimaa, and Pinus densiflora). The Coreopsis lanceolata community group, which exhibited vegetative characteristics of urban forest edge areas, was categorized into four units. The urban forest edges were classified into four communities (Indigofera bungeana, Lespedeza bicolor, Amorpha fruticosa, and Lespedeza cuneata). Accordingly, the vegetation structure of Mt. Goehwa was categorized into 10 vegetation unit systems. An importance value analysis showed the highest importance value for C. crenata at 6.7%, followed by P. rigida at 6.4%, and R. pseudoacacia at 6.3%, indicating that the ecological impact of plantation species can be significant on Mt. Goehwa. A community coefficient of similarity analysis revealed that the artificial and natural forests had similar species compositions; however, both forests differed from the urban forest edge. This variation was further confirmed by Detrended correspondence analysis(DCA), with similar results. Canonical correspondence analysis(CCA) showed that the artificial forest and natural forest community types were positively correlated with altitude, bare rock, and the present species. By contrast, the urban forest edge community types were negatively correlated with these factors.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.2
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• pp.89-102
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• 2015

This study contemplates the tendency of the examination questions for History of Korean Landscape Architecture. The study targets the questions of 'Landscape Architecture History' which has been set in the written test for National Qualification Test of a landscape engineer for recent 10 years from 2005 to 2014 and derives analyzable items based on the guidelines of question-setting presented by Human Resources Development Service of Korea. The results of the study are drawn as follows. First, among 5 areas composing Landscape History, the proportion of Korean Landscape questions is getting increased while that of Western ones is decreasing. Second, about 30 traditional trees and 11 types of traditional landscape elements including traditional facilities were shown in Korean Landscape questions. Besides, history, geographic, practical science, horticulture, anthology books and the 25 tradition landscape-related historic documents categorized as the garden painting data were found. And the kings from ancient era to Choseon Dynasty who were associated with the time of palace garden building, the builders or owners of the villas, the authors of the document and Chinese scholars also appeared. Third, there were no the questions of prehistoric times and Balhae Kingdom, whereas those of Choseon Dynasty were dominantly focused. Among the traditional sites of Choseon Dynasty, Byeolseo(villas) were set most, followed by Dosung or Gung-gweol(castle towns or palaces), houses, Nu Jeong Dea(pavilions) and Seowon(local schools) in order. Nak-an eupseong and Yong-ju sa were the only cases for a castle town and a temple each. Fourth, being associated with tradition spaces, the questions asked for understanding the detailed contents of time of sites' construction, builders, location features, building structures, ground plan types and the components s of garden. In addition, as a result of checking whether traditional landscape sites were shown in the set questions in 9 Korean Landscape textbooks, Dongchundang, Pungamjeonsa, Simgogseowon did not appeared. As a result of reviewing the tendency of the examination questions for History of Korean Landscape Architecture, the questions which ask minor facts without generality and which include difficult information and site uncomprehended in the textbook should be reconsidered.