• Korean Journal of Medicinal Crop Science
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• v.14 no.6
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• pp.347-353
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• 2006

This study was conducted to evaluate the vegetation structure and ordination of the Peucedanum japonicum Thunb. community by the Phytosociological method, floristic composition table on east coast of South Korea. The vegetation of Peucedanum japonicum Thunb. community was classified into 2 communities such as the Aster Spathulifolius community and the calystegia soldanella-Artemisia princeps community. Vegetation of the Peucedanum japonicum Thunb. community with the Aster spathulifolius community was shown southward, whereas vegetation of Peucedanum japonicum Thunb. community with the calystegia soldanella-Artemisia princeps community was shown northward from the base line of Pohang at North latitude of 36" 05'. Accordingly, the Peucedanum japonicum Thunb. community was grown commonly with the Aster spathulifolius community southward of the base line of Pohang, whereas it was grown commonly with the calystegia soldanella-Artemisia princeps community northward on the east coast. All environmental conditions of habitat taken together, the optimum habitat of Peucedanum japonicum Thunb. was at Ulsan geographically and the middle region of sea cliff topography, and was suitable for alkali. sandyloam.

• Journal of the Korean Institute of Landscape Architecture
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• v.19 no.3
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• pp.41-54
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• 1991

This study was executed to analyze the vegetational landscape structure and administration planning of Younguan Royal Tomb forest by the classification and DCA ordination were applied to the study are in order to classify them into several groups based on environmental variables. Also Younguan Royal Tomb forest comparison of a pair of photographs taken in 1920s and 1990. Sixteen sites were sampled with clumped sampling method in september 1990 and five quadrats were examined in each site. By classification and DCA, the plant community were divided into two groups(A. japonica community, P. densiflora, Quercus acutissima community) by the humus. Pinus densiflora community of actual vegetion covered 15.9%, Alnus japonica 6.5% and Quercus community 65.6% of the total area. And the afforested vegetation of P. koraiensis. P. rigida and Juglans mandshurica covered 13.2%. DCA ordination showed that successional trends of tree species seem to be from P. densiflora, Q. aliena to Q. acutissima in P. densiflora community and from A. japonica community of the upper layer. By the comparison of couple photographs between 1920s and 1990 we can recognize the change of historical landscape composed of P. densiflora community, A. japonaca and those community shall be conserved by the disclimax method, i.e. the broadleaf vegetation in the underlayer in the P. densiflora community should be cleared out. Otherwise the vegetational landscape sructure in Younguan Royal Tomb is successed to progress succession to Q. acutissima landscape.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.1
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• pp.24-31
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• 2010

This study was carried out to analyze vegetation and soil characteristic, and ordination of Scrophularia takesimensis population, Ulleung Island. The Scrophularia takesimensis population was classified into Aster spathulifolius for. oharai dominant population, Vitis amurensis dominant population and Scrophularia takesimensis typical population. The Scrophularia takesimensis population was located in elevation of 1m to 6m, in Ulleung Island. In the study sites, soil organic matter, nitrogen, available phosphorous, exchangeable potassium, exchangeable calcium, exchangeable magnesium and exchangeable sodium concentration, and cation exchange capacity, and soil pH were 9.1~19.1%, 0.19~0.52%, 87.1~196.7mg/kg, 2.0~2.8cmol+/kg, 5.4~5.9cmol+/kg, 5.9~8.8cmol+/kg, 4.4~4.8cmol+/kg, 20.3~26.7cmol+/kg, and 6.8~8.0, respectively. The Vitis amurensis dominant population was mainly found in the high percentage of total nitrogen, organic matter, CEC in comparison with Aster spathulifolius for. oharai dominant population.

• Korean Journal of Environment and Ecology
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• v.18 no.3
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• pp.279-287
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• 2004

To investigate the vegetation structure of the section of Nakdong-jeongmaek from Gajisan to Neungdongsan, fifty plots of 100$m^2$ at ten locations were set up. In accordance with the requirements of DCA(detrended correspondance analysis), which is an ordination technique, the sites were chosen contiguously with each other. The vegetation structure analysis showed Quercus dentata, Pinus densiflora, Q. mongolica to be the major species at canopy layer, Rhododendron schlippenbachii at the layer below the canopy and Tripterygium regelii at the shrub level. Shannon's diversity index was 1.5315～2.4005 per unit area of 500$m^2$. It appeared that the Quercus dentata forest of this ridge section of Nakdong-jeongmaek is about 30 or 40 years old.

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.4 s.27
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• pp.233-239
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• 2006

This paper aims to evaluate the operation efficiency of Korean RCC(Rescue Co-ordination Center)/RSC(Rescue Sub-Center) using DEA(Data Envelopment Analysis). for this evaluation, this paper use the quantitative data for DEA analysis with two inputs and four outputs and a qualitative data analysis with the use of expert assessment. The tool for integrating heterogeneous data is fuzzy logic model to decision support system. In this paper, therefore, RCC/RSC evaluates the priority for operation efficiency. The result are found as order as Inchon, Mokpo, Jeju, Donghae, Busan, Pohang, Yosu, Sokcho, Tongyeong, Ulsan, Taean, Gunsan RSC.

• The Korean Journal of Ecology
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• v.23 no.6
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• pp.439-444
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• 2000

Forest vegetation in Mt. Jangan County Park, Jeonlabuk-Do, Korea, was investigated by classification and ordination methods. By the cluster analysis (classification) method, nine groups were recognized as follows : Quercus serrata community, Quercus serrata- Carpinus laxiflora community, Cornus controversa community, Fraxinus mandshurica community, Carpinus laxiflora community, Quereus variabilis community, Quercus mongolica - Sasa borealis community. Quercus mongolica - Symplocos chinensis for. pilosa community and Quercus mongolica - Rhododendron schlippenbachii community. These groups showed differences in species composition and environmental characteristics, but Quercus mongolica - Sasa borealis community, Quercus mongolica - Symplocos chinensis for. pilosa community and Quercus mongolica - Rhododendron schlippenbachii community among them showed very similar floristic composition to each other. The interrelationship between the floristic composition of the vegetation and environmental factors was analysed by principal component analysis (PCA). Quercus mongolica community was distributed at a high altitude (900～1200 m above sea level). Fraxinus mandshurica community and Cornus controversa community were differentiated from the other communities with high contents of soil moisture and pH. On the other hand, Carpinus laxiflora community and Quercus variabilis community were distributed at places with adequate levels of soil moisture, soil organic matter. and at low altitude. In this study, the altitude and soil moisture were the main factors determining the forest vegetation. They were strongly correlated with the dominant compositional gradient at the localities examined.

• Journal of Ecology and Environment
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• v.34 no.4
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• pp.347-355
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• 2011

Effects of forest thinning on community level properties have not been understood yet in Korea. We investigated regeneration patterns and trajectories after a disturbance by applying a chronosequence approach. Light availability, litter and woody debris cover, and species composition were determined for twenty 50 m line-transect samples representing a disturbance duration gradient (within 11 years). Environmental factors such as light availability and coverage of woody debris and litter changed abruptly after thinning and then returned to the pre-disturbance state. Although species richness was gained at shrub and ground layer in a limited way in both forests, cover of various functional types revealed diversity in their responses. Notably, Alnus firma stands exhibited a larger increment of cover in woody plants. Ordination analysis revealed different regeneration trajectories between natural and planted stands. Based on ordination analysis, rehabilitated stands showed movement to alternative states compared with natural ones, reflecting lower resilience to perturbation (i.e., lower stability). Our results suggest that community resilience to artificial thinning depends on properties of the dominant species. But to get more explanatory ecological information, longer-term static observations are required.

• Journal of Korean Society on Water Environment
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• v.30 no.1
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• pp.68-79
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• 2014

There are marked differences in climate condition between east-facing slopes and west-facing slopes in Mt. Seorak (1,708 m). This study was conducted to find out the differences of benthic macroinvertebrate communities between both slopes of Mt. Seorak. Quantitative (Surber net; $30cm{\times}30cm$, mesh: 1mm) and qualitative (Hand net; mesh: 1mm) samplings ware carried out seasonally in each site which had 100-meter-high difference from November 2010 to November 2011. Most of the survey sites showed sound environmental conditions because they were located in the protection area of the national park. The benthic macroinvertebrates collected from all survey sites were composed of 158 species, 62 families, 17 orders, 7 classes and 5 phyla. DCA (Detrended Correspondence Analysis) ordination based on the abundance of benthic mactoinvertebrates showed that altitude was a major factor governing the structure of benthic macroinvertebrate community. There was no significant difference of the communities between both slopes.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.5
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• pp.27-38
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• 2013

This study was conducted to analyze the correlation between vegetation, environmental factors, and soil characteristic of an endangered species, Eleutherococcus senticosus. Eighteen quadrats in population zones of Seoraksan, Odaesan, Chiaksna, Duckhangsan, Sobaeksan, Juwangsan, and, Jirisan were set up and ordination was analyzed. In the study sites, soil pH, available phosphorous, organic matter and nitrogen were ranged from 5.06~5.43, 24.63~57.77mg/kg, 14.01~18.37%, and 0.63~0.75%, respectively. Eleutherococcus senticosus is classified into Morus bombycis dominant population, Cornus controversa dominant population, and Eleutherococcus senticosus typical population. The importance value of Acer pictum subsp. mono, Morus bombycis, Magnolia sieboldii, Cornus controversa, Tilia taquetii, and Ulmus laciniata in Eleutherococcus senticosus population were 23.76%, 23.61%, 18.06%, 17.82, 15.31%, and 13.57%, respectively. The correlation between vegetation and environmental factors of Eleutherococcus senticosus vegetation distribution were shown to be affected by altitude, slope, and direction.

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.340-343
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• 2001

In an electrical network, electrical power are transmitted by a various of protection, isolation and control electric circuit devices. This thesis deals with the protection function between circuit-breakers. The protective coordination concerns the behaviour of two devices placed in series in an electrical network, with a short-circuit downstream circuit-breaker. It has two basic principles: First, discrimination which is an increasing requirement of low voltage electrical distribution systems. Second, which is less well known: cascading, which consists of installing a device, whose breaking capacity is less than the three-phase short-circuit current at its terminals and helped by main circuit-breaker. The important advantage of cascading is to be able to install at a branch circuit-breaker of a lesser performance without endangering the safety of the installation for more economical usage. To determine and guarantee co-ordination between two circuit breakers, it is necessary to carry out a theoretical approach, first, and then confirm the results by means of standard tests. This is illustrated in appendix A of IEC 947-2.