• Journal of Korean Society of Transportation
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• v.23 no.8 s.86
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• pp.7-17
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• 2005

Transportation is from an individual mobility. Various efforts to propose specific values or the individual mobility have been conducted in diverse transportation environment. However, mobility studies for multimodal public transportation are rare especially on not the range of line but area. This study propose a method to calculate transit mobility indices as expanding mobility analysis from point-to-point to area-to-area, considering access time to transit facility, running time and transfer time of passengers. To extract mobility indices, we included walking as a lowest category of mode and set passenger car as a competitive mode to transit mode. This study propose three public transportation mobility indices as 1) how competitive public transportation facility is offered against passenger car 2) how convenient transit mode including walking is provided against passenger car from origin to destination and 3) how many various paths are presented to support passenger's travel between regions. These indices are tested on the Seoul metropolitan area with 10 lines of urban rail and about 420 lines of bus. In addition, we proposed two political applications of proposed mobility indices to increase public transportation mobility between two regions and to maximize the mobility of study area when a line is added in the area.

• Analytical Science and Technology
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• v.13 no.3
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• pp.269-276
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• 2000

Chromatographic retention mechanism of seven benzoic acids in RPLC were investigated. Inorganic salt is pertinent for the measurement of dead time in benzoic acid. Logarthims of capacity factor (log k') and Hildebrand solubility parameter (${\delta}$) showed proportional relationship which imply the hydrophobic effect of the retention mechanism in RPLC. Enthalpies of solute transfer showed inverse proportion to temperature and organic modifier ratio of the mobile phase. It was found that the S value showed positive slope in plot of log k' vs. volume fraction of water in mobile phase. Free energy change increases with increasing organic volume fraction. The hydrophobicity index, ${\varphi}_0$(organic volume fraction) is inversely proportional to column temperature.

• Journal of Environmental Impact Assessment
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• v.6 no.1
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• pp.33-45
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• 1997

Nowadays, the environmental conservation has become a hot issue. Also the sustainable city issue is recognized as one of the most important tasks to be solved urgently for urban development. Therefore, the current indicator for sustainable city has been analyzed only as a segment of the environmental indicator which is one kind of branch of social indicator. However, considering the degree of pollution and heightened concern, it is time to develop a new and improved framework for the analysis of the sustainable city indicator. This study aims for the development of sustainable city indicator and the examination of practical method for the use of them. Urban sustainable city indicators are based on the "Pressure-State-Response (PSR) framework" which has been adopted by Organization for Economic Cooperation and Development (OECD). The indicators suggested in this study is composed of the following categories: 1. Indicators of natural environment itself, such as land structure (available land use index etc.), bio-species (bio-diversity index etc.), environment resources (water quantity index etc.) 2. Indicators of relationship between man and environment, such as sustainability of using material (recycle of water index etc.), pressure size (pressure index on air etc.), effort of prevention (environmental basic facility index, etc.) 3. Indicators of environmental state, such as landscape and culture (historical & cultural index etc.), environmental pollution (air pollution index etc.) A sustainable city environment is necessary and obtainable, yet its realization seems to be difficult. The urban pollution problems have become more serious than ever before thus requiring much interest. Therefore, this kind of study is meaningful for the establishment of policy objective, and the development and management environmentally sound and sustainable cities.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.5
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• pp.64-72
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• 2008

The purpose of this study is to compare a habitat suitability grid unit included within a radius of 100m and $1km^2,\;2km^2,\;4km^2$ watershed units in order to predict suitable habitats for Chungcheong province's endangered leopard species(Prionailurus bengalensis). Other developed countries have carried out habitat assessment and established management policies for species conservation using such methods as HEP(Habitat Evaluation Procedures), HSI(Habitat Suitability Index) and GAP(Gap Analysis Program), etc. In accordance with these studies, many evaluation methods for habitat conservation have been proposed in Korea, but these studies are lacking in consideration of analytic units and general application of analysis results. This study predicted leopard habitat using a logistic regression analysis according to analytic units by data from 56 location and 8 sources of environmental data, including elevation, slope, forest area, land cover, roads, water, broadleaf trees, and human habitation. Moreover, the habitat suitability assessment unit was confirmed by a model comparison process encompassing model explanation. verification, and application on a regional scale. Results showed that assessment methods that took into consideration areas in and around the location points were beneficial in predicting habitat and that the assessment unit was appropriate for a 30m grid unit including areas within a radius of 100m and a $1km^2$ watershed unit in Chungcheong Province. This study suggests a method for regional habitat conservation to complement existing conservation area selection methods, and the results are expected to be used in conservation area selection and ecosystem management policies for endangered species.

• Journal of radiological science and technology
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• v.42 no.3
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• pp.217-222
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• 2019

The purpose of this study is to evaluate the dose distribution by gantry rotation and MLC moving speed on treatment planning system(TPS) and linear accelerator. The dose analyzer phantom(Delta 4) was scanned by CT simulator for treatment planning. The planning target volumes(PTVs) of prostate and pancreas was prescribed 6,500 cGy, 5,000 cGy on VMAT(Volumetric Modulated Arc Therapy) by TPS while MLC speed changed. The analyzer phantom was irradiated linear accelerator using by planned parameters. Dose distribution of PTVs were evaluated by the homogeneity index, conformity index, dose volume histogram of organ at risk(rectum, bladder, spinal cord, kidney). And irradiated dose analysis were evaluated dose distribution and conformity by gamma index. The PTV dose of pancreas was 4,993 cGy during 0.1 cm/deg leaf and gantry that was the most closest prescribed dose(5,000 cGy). The dose of spinal cord, left kidney, and right kidney were accessed the lowest during 0.1 cm/deg, 1.5 cm/deg, 0.3 cm/deg. The PTV dose of prostate was 6,466 cGy during 0.1 cm/deg leaf and gantry that was the most closest prescribed dose(6,500 cGy). The dose of bladder and rectum were accessed the lowest during 0.3 cm/deg, 2.0 cm/deg. For gamma index, pancreas and prostate were analyzed the lowest error 100% at 0.8, 1.0 cm/deg and 99.6% at 0.3, 0.5 cm/deg. We should used the optimal leaf speed according to the gantry rotation if the treatment cases are performed VMAT.