• Korean Journal of Environment and Ecology
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• v.9 no.2
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• pp.156-165
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• 1996

To investigate the forest structure and to suggest the management of vegetation landscape in Noinbong area, Pdaesan National Pa, twelve plots were set up and surveyed. According to the acalysis of classification by TWINSPAN, the community was divided by two groups of Carpinus laxiflora - Quercus mongolica community and the other is Betula costata - schmidtii - C. laxiflora community. It was found out that the successional stage of Noinbong forests was climax and introduced-climax by the analysis of species structure, similarity index and species diversity. The number of individuals was about 120~130 and species was 17 per 100m$^{2}$. Through the analysis of basal area and DBH class distribution, it was estimated that C. laxiflora, B. costata, and B. schmidtii will be clmax species instead of Q. mongolica in tree layer, and in the subtree layer, Acer pseudo-sieboldianum will be dominant species.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.3
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• pp.209-214
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• 2018

This paper suggests simple algorithm of facility location problem in perishable commodities that satisfy with minimum total transportation cost and within the transportation time constraint $L^*$. For this problem, Lee[4] suggests very complex algorithm that decides candidate facility locations, computes total transportation cost for each candidate facility location, then moving the location to optimal location for top two facilities. On the other hand, this paper simply determines the candidate facility locations within $L^*$ using subtree concept, and decides optimal minimal total transportation cost for top two locations in centralized area of required quantity using neighborhood concept.

• The Korean Journal of Ecology
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• v.17 no.2
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• pp.120-130
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• 1994

Stages of vegetation development on talus area were studied to examine temporal changes in species composition and vegetation structure, and to elucidate the mechanism of early patch formation. While ground coverage of lichens, which may form substrate for moss colonization and mitigate the heat-stress on rocks, decreased gradully, coverage of mosses increased slightly during primary succession. Ecological role of mossess related with water retention in community may be very important not only at pioneer stage but also at later stages because of little soil development on this talus area. Species diversity and species richness increased during the early stages of succession. Parthenocis년 tricuspidata and Sorbaria sorbifolia var. stellipa dominated in liana stage, Ulmus davidiana for. suberosa and Lindera obtusiloba in shrub stage, and Fraxinus rhynchophylla and Actinidia arguta in subtree stage, however, was composed of mixed forest of several tree species. U. davidiana for. suberosa, L. obtusiloba, Securinega suffruticosa and Rhus chinensis were relatively important woody species in early patch forming process. The results, however, suggested that early establishment on talus area might be strongly associated with chance for safe-site because both pioneer species and later species could take part in early patch forming process.

• The Korean Journal of Ecology
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• v.16 no.4
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• pp.459-476
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• 1993

Vegetational structure and successional sere were investigated for the evergreen and nearby deciduous broad-leaved forests in inland areas (Turyunsan, Pulgapsan) and south- western island areas (Hongdo, Chindo). The evergreen broad-leaved forests of the four areas showed a sera1 stage with an age structure mostly under fifty years old. Dominant evergreen broad-leaved species in canopy layer were Castanopsis cuspidata var. sieboldii, Machilus thunbergii, Quercus acuta, Q. stenophylla, Q. glauca, and Ncolitsea serzceu. Succession of the forest vegetation in the surveyed areas was proceeding from deciduous broad-leaved trees to evergreen broad-leaved trees. The species of climax stage were assumed to be Machilus thunbergii, iVeolitseu sericea and Dendropanax morbifera in canopy layer, Aucuba japonica and Machilus japonica in subtree and shrub layer.

• Journal of Ecology and Environment
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• v.30 no.4
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• pp.347-356
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• 2007

The structure and dynamics of Korean red pine stands established in the riparian zone were studied in the Tsang stream in Mt. Seorak National Park, in east-central Korea. Pine stands were classified into four successional stages, the initial, establishing, competitive, and stabilizing stages, based on the age distribution of a dominant tree, Pinus densiflora, the vegetation stratification, and the microtopography of the riverine environment. The stages usually corresponded to disturbance frequencies, depending on the horizontal and vertical distances from the watercourse. Stands of the initial and establishing stages lacked tree or subtree layers, or both. As stands progressed through the developmental stages, soil particle size became finer and moisture retention capacity was improved. The stand ordination reflected the developmental stage, and the species ordination differentiated species specializing in relatively dry and wet habitats. The results of the analysis of vegetation dynamics provided ecological information which will be useful for understanding the developmental processes of vegetation established in riparian zones. Species diversity indices usually increased across developmental stages, following the typical pattern for successional processes. We discuss the importance and necessity of riparian vegetation in Korea, where most riparian forests have disappeared due to excessive human land use.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.5
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• pp.38-46
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• 2004

This study was carried out to analyze forest vegetation in Seodaesan of Geumsan, Chungnam Province. Employing the releve method of Braun-Blanquet and quadrat method, 36 plots were sampled in forest of Seodaesan. The sub-communities were classified into Pinus densiflora, Acer pseudosieboldianum, and Carpinus laxiflora sub-community of Quercus mongolica community. The importance values were 77.07 in Quercus mongolica, 40.79 in Pinus densiflora, 17.03 Fraxinus rhynchophylla, 14.06 in Fraxinus sieboldiana, 13.99 in Quercus serrata, 12.93 Acer pseudosiebotdianum. Coverage rate was 84.6% in tree layer, 52.8% in subtree layer, 29.1% in shrub layer, 27.9% in herb layer, respectively. Most of the DBH of Quercus mongolica and Pinus densiflora was between 5cm and 20cm. Therefore, Quercus mongolica and Pinus densiflora might be dominant species in the study area for several decades. Acer pseudosieboldianum and Carpinus laxiflora sub-communities were distributed mainly in a high-altitude and northern and north-western area. Pinus densiflora sub-community was distributed mainly in a low-altitude and western area.

• Korean Journal of Environment and Ecology
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• v.8 no.1
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• pp.58-67
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• 1994

Object of this study is to suggest the plan for natural vegetation restoration and management by ecological approach. The concept of biotope planting technique was introduced in order to restore the natural vegetation in the northern part of Mt. Nam in Seoul, and Quercus mongolica forests was surveyed so as to obtain the basic data. This study focused on the vegetational context between northern part of Mt. Nam and develop-reserved site. The results are following ; 1. It is suitable to plant 25~30 trees in $100\m^2$ with trees of DBH 10cm and below at intervals of about 2m in canopy layer. In the case of subtree layer of DBH 2cm, about 30 trees were planted at an Intervals of 1.5~2m around in $100\m^2$. 2. In the last step of nature vegetation restoration, it is desiable that canopy density is $5/100\m^2$ and 녀btree one is 10~20/$100\m^2$. 3. Management plans was proposed to use the native species of Mt. Nam around and to investigate the ecological situation once a year such as species introduce, dead-tree, soil, fauna etc.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.3
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• pp.358-363
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• 2014

In this paper, we present two constructions of the attribute-based broadcast encryption(ABBE) algorithm. Attribute-based encryption(ABE) algorithm enables an access control mechanism over encrypted data by specifying access policies among private keys and ciphertexts. ABBE algorithm can be used to construct ABE algorithm with revocation mechanism. Revocation has a useful property that revocation can be done without affecting any non-revoked uers. The main difference between our algorithm and the classical ones derived from the complete subtree paradigm which is apt for military hierarchy. Our algorithm improve the efficiency from the previously best ABBE algorithm, in particular, our algorithm allows one to select or revoke users by sending ciphertext of constant size with respect to the number of attributes and by storing logarithm secret key size of the number of users. Therefore, our algorithm can be an option to applications where computation cost is a top priority and can be applied to military technologies in the near future.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.2
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• pp.151-157
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• 1990

This paper presents a method for rapid wire frame drawing of the 3D objects represented by the CSG scheme. When the two CSG trees are combined into one, the intersection parts of the polygons constituting the object corresponds to each subtree are computed, and the boundary representation of the combined object is obtained according to the given combinational operator and stored in the root node. The boundary representation in the root node is used in the wireframe drawing of the object and later computation of boundary representation. Bezier surface is taken as one of the primitive object the scan-line algorithm is used, which subdivides each scan-line into the spans where no polygon is intersected, and renders each span with the CSG representation of the object.

• Korean Journal of Environment and Ecology
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• v.18 no.2
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• pp.131-141
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• 2004

To investigate the vegetation structure of mountain ridge from Namdeogyusan to Sosajae in Baekdudaegan which is the greatest chain as well as the major ecological axix of the Korean Peninsula, sixteen sites(size 500$m^2$) were set up and surveyed. By using TWINSPAN technique, the plants community was divided and summarized into five groups, those are four Quercus mongolica dominated communities and Quercus mongolica-Pinus densiflora community. Four Quercus mongolica dominated communities have differentiated from subtree dominant species. Vegetation structure of each community have explained using important percentage by layer. In descriptive analysis, average number of species is 27.8$\pm$7.5 and average number of individuals is 687.6$\pm$326.8 at unit area(500$m^2$).