• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.9
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• pp.688-698
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• 2009

Using the multi-dimensional, multi-phase, nonisothermal Polymer Electrolyte Fuel Cell (PEFC) model presented in Part I, the effects of land/channel flow-field on temperature and liquid saturation distributions inside PEFCs are investigated in Part II. The focus is placed on exploring the coupled water transport and heat transfer phenomena within the nonisothermal and two-phase zone existing in the diffusion media (DM) of PEFCs. Numerical simulations are performed varying the land and channel widths and simulation results reveal that the water profile and temperature rise inside PEFCs are considerably altered by changing the land and channel widths, which indicates that oxygen supply and heat removal from the channel to the land regions and liquid water removal from the land toward the gas channels are key factors in determining the water and temperature distributions inside PEFCs. In addition, the adverse liquid saturation gradient along the thru-plane direction is predicted near the land regions by the numerical model, which is due to the vapor-phase diffusion driven by the temperature gradient in the nonisothermal two-phase DM where water evaporates at the hotter catalyst layer, diffuses as a vapor form and then condenses on the cooler land region. Therefore, the vapor phase diffusion exacerbates DM flooding near the land region, while it alleviates DM flooding near the gas channel.

• Journal of the Korean association of regional geographers
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• v.18 no.4
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• pp.414-432
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• 2012

Land price is a kind of text to read urban spatial structure. The purpose of this paper is to inquire into the characteristics of Daegu's urban structure and its change in time through exploring spatio-temporal variations of land price with a detailed spatial and temporal resolution. To achieve this, land value surfaces were represented using the officially assessed land price every other year from 1995 to 2011. Through mapping and exploring spatio-temporal patterns and fluctuation rates of land price for this period, changes in urban structure, the effects of local decision makings such as Greenbelt adjustment, housing site development, and gentrification, and the effects of business fluctuations or policies at global or national scales could be caught. In addition, the trends for suburbanization and multi-centric urban form could be examined from the results of a negative exponential model explaining the effect of distance from an urban center on spatial variation of land price. These results demonstrate that urban analysis using land price mirroring spatial decision making at various scales could deepen understanding for internal structure and change of a city and provide useful information for establishing regional and urban development policies and evaluating their effects.

• Journal of the Korean Institute of Landscape Architecture
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• v.13 no.1
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• pp.43-66
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• 1985

Korea needs proper and rational public policies on conservation and use of forest land and other natural resources because of the accelerating expansion of national land developments in recent years. Unfortunately, there is no systematic planning system to support the needs. Generally, forest land use planning needs suitability analysis based on efficient land classification system. The goal of this study was to classify a forest land using multivariate satistical methods. A case study was carried out in winter of 1983 on a mountainous area higher than 100m above sea level located at Mt. Kwanak in Anyang -city, Kyung-gi-do (province). The study area was 19.80 km$^2$wide and was divided into 1, 383 Operational Taxonomic Units (OTU's) by a 120m$\times$120m grid. Fourteen descriptors were identified and quantified for each OTU from existing national land data : elevation, slope, aspect, terrain form, geologic material, surface soil permeability, topsoil type, depth of the solum, soil acidity, forest cover type, stand size class, stand age class, stand density class, and simple forest soil capability class. For this study, a FORTRAN IV program was written for input and output map data, and the computer statistics packages, SPSS and BMD, were used to perform the multivariate statistical analysis. Fourteen variables were analyzed to investigate the characteristics of their fire quench distribution and to estimate the correlation coefficients among them. Principal component analysis was executed to find the dimensions of forest land characteristics, and factor scores were used for proper samples of OTU throughout the study area. In order to develop the classes of forest land classification based on 102 surrogates, cluster and discriminant analyses of principal descriptor variable matrix were undertaken. Results obtained through a series of multivariate statistical analyses were as follows ; 1) Principal component analysis was proved to be a useful tool for data selection and identification of principal descriptor variables which represented the characteristics of forest land and facilitated the selection of samples.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.6
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• pp.911-920
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• 2010

The basic principles in the "Spleen-stomach theory(脾胃論)" sets up the phases and roles of spleen-stomach (脾胃) by establishing Earth(地 坤 土) and exposing the reality of spleen-stomach(脾胃) of human body which has its own shape and form with Heaven's reality exhibited. The meaning of Earth is based on the constant meaning of Earth in 'Earth Original-Earth as extended and stable ground(坤元一正之土)' giving form and shape, and Earth's movement with circulation, then exposes itself as 'Earth as plowing land(耕種之土)' concerning both the application of Five Phases and the physical characteristics of Earth. The Yin-Yang recognition on Earth is revealed as Yin Earth(陰土)-Yang Earth(陽土). Spleen(脾) was established as Yin Earth(陰土) and Stomach(胃) as Yang Earth(陽土). The seasonal assignment of Earth is Indian Summer(長夏), which is divided from Summer, and becomes Heat(熱), and the Yin-Yang recognition of Earth comes to be the meaning of the center and border. According to the Five Phasic recognition, it becomes Earth(土) and gets to be Dampness(濕) in accordance with Six Qi(六氣). 'Extreme Yin(至陰)' indicates Qi's status exposing the fundamental meaning regarding the role of creating, changing, and propelling Spleen-Stomach(脾胃) as a characteristic Yin Earth. Earth comprehends 'Four Courses(四維)' meaning, recognizes them as four parts of the 12 Earth's Branches(辰戌丑未) and the terminals of four seasons(四季之末), and has the meaning of the president of the change in four seasons. The theory of principle in the "Spleen-stomach theory(脾胃論)" stands on the basis of the 'Form Qi theory(形氣論)' and that of 'Upbearing, Downbearing, Floating, and Sinking theory(升降浮沈論)'. It manifests the theory of movement in the interaction between Form(形) and Qi(氣), and 'Qi Interior Form Exterior(氣裏形表)' indicates that Qi(氣) moves interiorly and Form(形) exteriorly.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.2
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• pp.104.1-104.1
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• 1997

The purpose of this study is to grasp the characteristics of user''''s response to perceived safety and visual preferences for outdoor green spaces by the types of campus layouts. This research was investigated by color slide ratings and questionnaire survey to the students who are majoring in Landscape architecture in three universities locating at Taegu area. Two research sites have similarities in many ways but have differences in campus land form and design type such as ''''Closed'''' and ''''Open'''' types. Major results were summarised as follows ; 1. As a result of the slide test, the high degree of visual preference was shown in the campus that is ''''Closed'''' type. However the degree of perceived safety was lower than that of in Youngnam Univ. campus. 2. According to the result of the comparative analysis between user''''s perceived safety and visual preferences in each campus, the degree of perceived safety at ''''Closed'''' type was lower than that of ''''Open'''' type, but the degree of visual satisfactioni was higher at ''''Closed'''' type. 3. The factors affecting visual preference in campus were shown as density of wood, land form, and diverse type of the spaces. On the other hand, the factors affecting perceived safety were ''''enclosed space by wood'''' at the day time, and ''''the condition of lighting'''' at night. 4. Regarding gender differences in sensation of each space variables, female users showed higher satisfactio on the scenic beauty. 5. Regression analysis showed that general satisfation was determined by the variables such as ''''arrangement'''', familiarity'''', ''''cleanness'''', and ''''closed feeling'''', in Kyungbook Univ. And in Youngnam Univ. , the variables were ''''texture'''', ''''perceived beauty'''', ''''cleanness'''', and ''''complexity'''' respectively. 6. In conclusion, campus users wanted the outdoor spaces that have various land form and somewhat ''''open-closed'''' mixture type, which has a good ''''Edge Effect'''' to satisfy both aspects in safety and visual preferneces.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.2
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• pp.104-116
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• 1997

The purpose of this study is to grasp the characteristics of user's response to perceived safety and visual preferences for outdoor green spaces by the types of campus layouts. This research was investigated by color slide ratings and questionnaire survey to the students who are majoring in Landscape architecture in three universities locating at Taegu area. Two research sites have similarities in many ways but have differences in campus land form and design type such as 'Closed' and 'Open' types. Major results were summarised as follows ; 1. As a result of the slide test, the high degree of visual preference was shown in the campus that is 'Closed' type. However the degree of perceived safety was lower than that of in Youngnam Univ. campus. 2. According to the result of the comparative analysis between user's perceived safety and visual preferences in each campus, the degree of perceived safety at 'Closed' type was lower than that of 'Open' type, but the degree of visual satisfactioni was higher at 'Closed' type. 3. The factors affecting visual preference in campus were shown as density of wood, land form, and diverse type of the spaces. On the other hand, the factors affecting perceived safety were 'enclosed space by wood' at the day time, and 'the condition of lighting' at night. 4. Regarding gender differences in sensation of each space variables, female users showed higher satisfactio on the scenic beauty. 5. Regression analysis showed that general satisfation was determined by the variables such as 'arrangement', familiarity', 'cleanness', and 'closed feeling', in Kyungbook Univ. And in Youngnam Univ. , the variables were 'texture', 'perceived beauty', 'cleanness', and 'complexity' respectively. 6. In conclusion, campus users wanted the outdoor spaces that have various land form and somewhat 'open-closed' mixture type, which has a good 'Edge Effect' to satisfy both aspects in safety and visual preferneces.

• Journal of the Korea Institute of Building Construction
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• v.8 no.2
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• pp.45-52
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• 2008

In today's construction, there has been an increase in the construction of high-rise buildings due to the need to maximize land usage. Framework affects not only the entire construction duration and cost, but also subsequency construction activities such as electrical, mechanical, and finishing works. Especially, proper formwork is a influential factor of productivity in the framwork of reinforced concrete construction. To that reason, a table form of system form is more frequently used than conventional form. However, an initial cost of the table form is high and a reused table form needs for workers to repair damaged table forms. Therefore, the goal of this study is to introduce euro-unit table form. The results from the application of euro-unit table form to high-rise residentia building construction are as follows : (1) The cost of producing table form reduced by 16%, and (2) The time of producing table form was slumped by 35%, and (3) The labor force needed for form work declined 21%.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.3
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• pp.1-22
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• 2020

This study was conducted as a basic data for preparing future management alternatives by analyzing the status and characteristics of invasive alien plants by land-use type based on the formation of a new town in Goyang Siksa district. As a result, the invasive alien plants in the Goyang Siksa district were 20 families 46 genera 57 taxa; according to the land-use type, the residential area(Wi City apartment complex) is 7 families 10 genera 12 taxa, the public facilities area(Dongguk University campus) is 17 families 40 genera 47 taxa, the mixed forest is 5 families 10 genera 10 taxa, the rice paddy is 5 families 6 genera 7 taxa, river(Mt. Gyeondal creek) is 7 families 13 genera 15 taxa were appeared. The life-form of invasive alien plants in Goyang Siksa district is annuals, the origin is America, the introduction time is third period(1962~the present), and the diffusion grade is wide spread(5 grade) species. It was higher than other types. The naturalization index by location was 31.9% in river(Mt. Gyeondal creek), 21.2% in rice paddy, 16.7% in mixed forest, 15.5% in public facilities area(Dongguk University campus), and 8.5% in residential area(Wi City apartment complex). As a result of comparing the naturalization index by regions with the previous studies, it is judged that there are differences due to the environment such as urbanization progress, size, area, population inflow and location conditions. Although many new towns have been established to date, there is a lack of research on flora (including invasive alien plants) as a basic data for preparing management alternatives. Therefore, Through this study, basic data on the management of exotic plants by land use unit in urban areas can be provided.

• Land and Housing Review
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• v.4 no.2
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• pp.193-200
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• 2013

Construction duration in construction project is an important factor which affects project cost. Advanced countries have reduced project cost by time shortening. Even though domestic construction companies have tried to time shortening, they yet failed to find systematic method for time shortening. Typically, duration of structural framework is affected by stripping time of form. Therefore, it need to shorten the stripping time of form for time shortening of structural framework. In this study, specimens of high-early-strength concrete were manufactured with variety conditions and compressive strength was tested. This study proposed stripping time of side and slab forms using test results. The stripping time of form was shortened when using high-early-strength concrete in structural framework by the test results. The result of this study will be useful for time shortening of structural framework.

• Journal of Environmental Impact Assessment
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• v.16 no.4
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• pp.267-275
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• 2007

In this study, relationship between the air pollution of Siheung city and the relative contribution of automobiles to the city's pollution was evaluated for the first time. Then, new air pollution exposure index was developed through simulation. Using the newly developed index, two different urban development scenarios were compared to present a sustainable urban development plan to reduce air pollution from the land utilization point of view. According to the result of this simulation, air quality of the city was found to be affected significantly by human activities. More populated area showed worse level of air quality. Any development in the city resulted in more automobile activity and deterioration of air quality. This simulation result thus explains that a rapid increase of automobiles accompanied by the land development near local roadsides in the city is the major cause of air pollution in Siheung city. In this study, if urban activities are vigorous in an area with high air pollution, people are more likely to be exposed to air pollutant under the bad environmental conditions. On the other hand, if urban activities are less vigorous in an area with high pollution or if urban activities are vigorous in an area with less pollution, the environmental condition was positive. The APEI (Air Pollution Exposure Index) was developed based on these considerations. Scenarios 1 and 2 were compared and analyzed using APEI. In result, scenario 1 is the case in which land is developed and used in an environmentally favorable manner. From this study, it was proved that the impact of air pollution on human health can be minimized with proper land use. The result form the current study can be used as the basic information to solve problems from improper land utilization and air pollution (by road traffic). It also can be utilized to evaluate air pollution level according to land use and road characteristics and to help to choose the best location of land use to comply with the road function and status.