• Journal of the Korean Geographical Society
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• v.33 no.3
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• pp.365-376
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• 1998

The goal of this study is to find the geomorphic variables contolling gully development on hillslopes following deforestation. Two possible geomorphic processes, surface erosion and mass movement were reviewed to compare the characteristics and geomorphic variables involved. The research objective in this paper is to find the variables and the statistical model which can explain gully density in the study area. Gully density was selected as a response variable. For log gully density, the best subset regression was found to have the variables such as area, surface length, and surface width. Log area is the most significant predictor. Even with several outliers, the normal probability plot of the residuals from this regression looks straight. So, area, surface length, and surface width explain half of the variance in gully density.

• Journal of the Korean housing association
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• v.22 no.3
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• pp.101-111
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• 2011

This study was conducted to investigate the indiscriminate development occuring as a result of high-density land use per lot in residential areas of Seoul, which mainly consist of detached houses. The primary goals of this study were: (1) to suggest a block unit development method as an alternative architectural method of the current uniform development, in which high-rise and high-density apartments are usually built; and (2) to check the feasibility of the suggested method. Based on the analyses of the existing block composition types of residential areas, the prerequisite planning indices for applying a collective housing model were investigated. Subsequent to applying a collective housing type within each unit block, the collective housing model was analyzed. The results of the analyses showed that indiscriminate development was rampant in detached urban houses areas, and more than 70% of the buildings constructed before the 1980s needed re-development. The feasibility of the models was investigated depending on the models of low-rise and high-density collective housing, which utilize various block arrangements such as the court type, linear type, villa type, and composite type. The results of this study showed that the newly applied low-rise and highdensity multiple dwelling housing model in urban individual residential area significantly contributed to creating a good living environment in terms of both physical and psychological aspects.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.2
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• pp.244-251
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• 2009

Porous media have especially large surface area per volume, which contain complex fluid passage. If porous media can be applied to cool a CPU or an electronic device with large heat dissipation, it could result in heat transfer enhancement due to the enlargement of the heat transfer area and the flow disturbance. This study is aimed to identify the heat transfer and pressure drop characteristics of high-porosity metal foams in a horizontal channel. Experiment is performed with the various heat flux, velocity and pore density conditions. Permeabilities, which is deduced from Non-Darcy flow model, become lower with increasing pore density. Nusselt number also decreases with higher pore density. High pore density with same porosity case shows higher pressure loss due to the increase of surface area per unit volume. The fiction factor decreases rapidly with increase of Reynolds number in Darcy flow region. However, it converges to a constant value of the Ergun coefficient in Non-Darcy flow region.

• Journal of environmental and Sanitary engineering
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• v.21 no.4 s.62
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• pp.61-76
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• 2006

A Line Density algorithm was developed to quantify the sea surface temperature distribution using NOAA Sea Surface Temperature(SST) data and Geographic Information Systems(GIS), In addition, a GIS based automation model was designed to extract the Line Density Indices were determined by applying K-means Cluster. SST data in terms of March to May obtained on the coastal area of the Uljin from 2001 to 2004 in spring were used to make two data sets of average sea water temperature map in terms of year as well as month. From the result it was formed that water temperature gradient in April was the strongest among the other months, In particular very strog formation of oceanic front as well as temperature gradients were observed in front of the coastal area around Wonduk and Jukbyeon countries. Because those coastal area is a confront zone of two cold and a warm. It is expected that the development of a Line Density Algorithm would contribute to quantify of the SST for the research of Sea Surface Front(SSF) related to marine life management and the sea environmental conservation.

• The Journal of the Korea Contents Association
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• v.11 no.5
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• pp.466-473
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• 2011

The purpose of this study is to analyze the distribution of the building area and find the characteristics of development density where the areas to perform special functions as residential, commercial, and business area in Seoul. As a result of classification of the regions with the component ratio of building area ratio by types, the greater part of Seoul is residential areas and only a small part of Seoul have business function. Contrary to the Kang-Nam business districts, the central business districts have few or no houses. It is concerned that the redevelopment projects, such as New-Town, make Seoul more high- density. The industrial area lost the attractiveness as a resident in spite of businesses or infrastructures. So the industrial area will be the best place for reduce journey-to-work distance if improve housing conditions. As well as management of density, management of use is also required for effective landuse and green-growth city.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1243-1244
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• 2006

Five kinds of double stacked 385 (55 x7) filamentary Bi2212/Ag round wires and 55 filamentary tapes with different Ag ratios (silver area/superconductor area) have been fabricated via PIT method, and the effects of Ag ratio and processing factors on critical current density were studied. The effects of the maximum temperature and average filament diameter on critical current density were also studied. The wire of 0.74 mm diameter having Ag ratio 3.7 showed critical current density of $2,218\;A/mm^2$ at 4.2 K, 0 T.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.29 no.1
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• pp.87-103
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• 1999

Purpose: This study was undertaken to quantitatively estimate the degree of the damage and recovery of the irradiated rat condylar cartilage using the Image Analyzer. Materials and Methods: Experimental animals were 16 male rats of the Sprague-Dawley strain at the age of 20 day irradiated with the dose of 10 Gy in their head and neck region. Four rats were sacrificed at the each of the following time intervals - 1, 4, 7 and 14 days, respectively. The same number of control group animals were sacrificed at the each age of 21. 24, 27 and 34 days, respectively. The specimens were stained with 0.5％ toluidine blue and examined with light microscope. The condylar cartilage was divided into 4 zones; fibrous zone, proliferating zone, upper hypertrophic zone, and lower hypertrophic zone. And then, the proliferating zone was subdivided into 2 layers - upper and lower layer, and upper and lower hypertrophic zone were subdivided into three layers, respectively - upper, middle and lower layer. With the aid of Image Analyzer, morphometric analysis was performed. The thickness, the numerical density of cells, the cell area density, the extracellular matrix area density, the mean area of single cell, the mean area of extracellular matrix per single cell were measured and analysed. Results: In the experimental group, the thickness of the fibrous zone was slightly increased and that of the proliferating zone and the upper and the lower hypertrophic zone was markedly decreased. With time, the thickness of the fibrous zone was gradually increased and that of the proliferating zone and the upper and the lower hypertrophic zone was steadily in the decreased state. The numerical density of cells of the proliferating zone was increased on post-irradiated 1 day, but decreased after post-irradiated 4 day, and that of the upper hypertrophic zone was decreased. The numerical density of cells of the lower hypertrophic zone was decreased in the early stage and then was decreased or not significantly different from that of the control group with time. In the experimental group, the cell area density of the fibrous zone and the proliferating zone was decreased in the early stage and then gradually increased or not significantly different from that of the control group with time. The cell area density of the upper and the lower hypertrophic zone was varied with time. The extracellular matrix area density value were totally opposite to the cell area density values: The mean area of single cell of the fibrous zone and the proliferating zone was .decreased on post-irradiated 1 day, and increased after post-irradiated 4 day. The mean area of single cell of the upper hypertrophic zone was varied with each layer and time. In the experimental group, the mean area of extracellular matrix per single cell of the fibrous zone was not significantly different with control group, and that of the proliferating zone was decreased on post-irradiated 1 day, and increased after post-irradiated 4 day. The mean area of extracellular matrix per single cell of the lower hypertrophic zone was increased in the early stage. and that of upper hypertrophic zone was varied with each layer and time. Conclusion: The condylar cartilages of rats were affected by irradiation, but the changes were vaned with each layer and time. By morphometric analysis. the changes of the cells of the condylar cartilage of irradiated rat could be calculated quantitatively.

• Korean Journal of Environment and Ecology
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• v.18 no.2
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• pp.236-248
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• 2004

This study was carried out to propose improvement planting method by the research and analysis of planting concept, planting density, planting style and pattern in apartment complex, Seoul. Survey sites were selected by reflecting the change of green area ratio : Hawgok Jugong apartment complex, Gangseo-gu(1974), Samik-green apartment complex, Gangdong-gu(1980), Dongsindaea apartment complex, Gangseo-gu(1992). Green area in apartment complex was classified with front green area, side green area, and back-side green area. Planting concept that composed of landscape planting concept but anyother concept was not, was similar to all sites not differ from creation time. And planted species was not differ from planting style. Planting density was of both conopyㆍunder story layer was 0.0∼0.2 tree/$m^2$, and that of shrub layer was 0.0∼0.5 tree/$m^2$ Shrub layer planting density was insufficient and the density was not changed according to the creation time. Canopyㆍunderstory and shrub was planted to another green space, not concern with multi-layer structure. Planting pattern was utilized to single planting, linear planting, and random triangle planting, but it was not to the change that in each green space planting concept. Green area in apartment complex should be variety according to planting density, planting structure and planting pattern. And we should get the function of covering and beauty in case of front green space, that of ecological environment and increasing green volume in case of back-side green area, that of increasing green volume in case of side green area, apartment complex.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.1 no.1
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• pp.105-111
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• 2006

Objective : The aim of this study was to evaluate association between lumbar spinal stenosis, one of degenerative diseases, and bone mineral density. Methods : We monitored 9 lumbar spinal stenosis patients in women above 50 years, visiting outpatient clinic of the Jaseng Oriental Medicine Hospital between January 5 2006 and March 31, 2006. They were diagnosed by radiologist ist after taking Magnetic Resonance Imaging(MRI). The cases were Investigated the bone mineral density using Dual Energy X-ray Absorptiomerty(DEXA). and then Picture Archiving Communication System(PACS) were used to assess correlation between lumbar spinal stenosis and bone mineral density. Results : 1. In comparison of the spinal canal area and lumbar spine 2 level bone mineral density, the data showed a significant result 2. The data, between spinal canal area and lumbar spine 1-2 level bone mineral density, indicated a significant result. 3. Also, the result of comparison between spinal canal area and the lowest value of bone mineral density showed significance. Conclusions : It showed that there is a statistically significant correlation between lumbar spinal stenosis and bone mineral density.

• Asian Journal of Turfgrass Science
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• v.3 no.1
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• pp.5-12
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• 1989

Tiller numbers per Unit area were increased as plant density heightened followed by little difference in tiller number in 110 days after transplanting(ll0DAT), this being caused by the immediate increment of tiller since' 90DAT During the growth period, the greatest number of green leaves per unit area was attained in 90DAT of both 160-density and 200-density plots, and in l00DAT of 40-, 80-, and I 20-density plots. Thus, the period to reach the maximum green leaf number with the high plant density was earlier than with the' low plant density. The increment of plant density increased the DM weight of ahoveground part and, with 40-densitytreatment. DNI weight was increased 6.1 times as much up to 110DAT as up to 7ODAT but 2 to 2.9 times with other ehe'nsity treatments. The' rate of increase in stolon length was greatest at the period between 80 and 90DAT when DM weight of stolon showed a large increment. Meanwhile, the average number of stolon was 1.7 at 70DAT but was increased up to 10 at 110DAT probably due to accelerative appeance of Ist stolon branch since 8.0DAT. DM weight of stolon was found to exceeded that of root after 90DAT Thus it was concluded that, when turfs is estahlished from sprig. it may be desirable for first mowing practice to be made at least within l00 days after planting.