• Journal of the Korean GEO-environmental Society
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• v.12 no.12
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• pp.47-54
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• 2011

Consolidation behavior of soft clay is generally to be affected by its compressibility and deformation characteristics. Especially, soil permeability depends on soil characteristics including its type of anisotropy. Coefficient of permeability of soft clay is mostly estimated by using laboratory(Oedometer test) and in-stiu piezocone test. The permeability characteristics of soft clay is estimated by excess pore pressure dissipation test results. In this study, the tests were performed to find out the validity of the existing theoretical formula in clay by pore pressure dissipation test and laboratory test results. After grasping of variation the coefficient of permeability ratio(${k_{h}/k_{v}}$) in different clay soils, it was found out adequate solution of in-stiu permeability ratio(${k_{h}/k_{v}}$). Piezocone tests and laboratory tests were performed at the site of pilot project of ground improvement at Yangsan-Mulgeum, Gyeongsangnam-do. Comparisons of the estimated values of ${k_{h}/k_{v}}$ using piezocone tests results and those from laboratory consolidation tests were carried out. Test results show that values of ${k_{h}/k_{v}}$ by piezocone test result(5.85) is similar of it's laboratory test(5.28).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.1
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• pp.81-91
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• 2019

Although the number of users of urban railways is greatly influenced by the land use plan around the railway station, Korea has been studying this problem in a small scale, so that the entrance width is uniformly calculated irrespective of the land use plan, And there is little deviation. Therefore, this study aims to establish a demand estimation model for the entrance and exit of urban railway stations. For this purpose, the demand, land use area, and socioeconomic indicators for each of the 20 urban railway stations were surveyed at 200m and 500m Regression model. The model is based on the assumption that the dependent variable (response variable) of the model is set to 1 day, peak 1 hour, peak time 5 minutes, Education, and park) and socioeconomic indicators (population, employer, employee, and student) as independent variables (explanatory variables). As a result, it was analyzed that the fit of the model is more statistically significant when the use area of the land use by 500 meters of the center radius of the city rail is used as an independent variable and the demand for the daily use of the railway station is used as a dependent variable. The purpose of this study is to estimate the optimal size of urban railway entrance in order to improve the mobility of the user and the transportation weak in urban railway station.

• Journal of the Korean Association of Geographic Information Studies
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• v.1 no.2
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• pp.14-25
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• 1998

The purpose of this paper is to select proposed waste facilities sites after consideration of relative importance of siting factors. From the literature review we have established the siting factors affecting selecting waste facilities sites, and constructed hierarchy of siting factors to evaluate the relative importance of the factors using Analytical Hierarchy Process(AHP). After mail surveying of expert group, we have analyzed the relative importance of siting factors affecting waste facilities. We have constructed Geographic Information System(GIS) of raster type, based on seventeen theme maps of siting factors on waste facilities, to select the proposed waste facilities sites after consideration of the relative importance of the siting factors for Gyongsan city, in Korea. After applying linear combination method, and factor combination method to overcome the methodological limitations of land suitability analysis, we have found five proposed sites, where intersected with proposed sites obtained from the two methods. From this research we have found that 1) methodologically, using GIS for selection of proposed waste facilities sites turned out to be highly useful, 2) application of relative importance of siting factors and two methods of land suitability analysis in selection of proposed waste facilities sites are pertinent enough to provide valid and reliable results, and 3) the research methods and approach employed in this research will be highly useful in site selection of other major facilities.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.337-337
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• 2018

시민들은 삶의 질 향상 및 친환경적 어메니티의 수요 증가로 수변지역에 대한 관심이 집중되고 있다. 수변지역은 물에 인접한 지역이라 친수 공간으로서의 긍정적 기능을 많이 포함하고 있으나, 방재 측면에서는 많은 위험성을 내포하고 있다. 수변지역에 적합한 물순환 기준을 정립하여 보다 안전하고 건강한 친수공간의 접근성을 시민들에게 제공하여야 한다. 본 연구에서는 수변지역을 물수지 분석 방법으로 접근하여 강우, 침투, 증발산, 유출 등의 변수들이 LID(Low Impact Development) 기술 적용에 의해 빗물의 저장과 침투가 유출의 감소로 이어질 수 있도록 물순환 기준을 산정해보았다. 물순환은 강우를 기준으로 처리할 목표량을 계획한 후, 침투량을 우선 산정하고 나머지 유량은 저장으로 처리하도록 프로세스화 하였다. 먼저, 물순환 목표량은 대상지의 강우와 유출 특성을 분석하여 기준을 수립한다. 이후 대상지의 토지이용과 토양 등의 지형학적 상태를 고려하여 각각의 세분화된 소유역의 침투량 규모를 산정한다. 목표량에서 침투량을 제한 나머지 유출량은 빗물통과 같은 LID 저장 기술로 해결할 수 있도록 저장 규모를 산정한다. 이상의 프로세스로 수변지역의 물순환 목표량을 LID 기술의 저장과 침투의 방법으로 해결할 수 있다. 이와 같은 방식으로 전국 각지의 수변지역 특성에 맞는 적합한 물순환 기준을 제시하여 보다 안전하고 건강한 친수 공간을 설계할 수 있도록 한다.

• Korean Journal of Environmental Biology
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• v.40 no.2
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• pp.214-223
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• 2022

Among migratory insect pests, Mythimna seperata and Cnaphalocrocis medinalis are invasive pests introduced into South Korea through westerlies from southern China. M. seperata and C. medinalis are insect pests that use rice as a host. They injure rice leaves and inhibit rice growth. To understand the distribution of M. seperata and C. medinalis, it is important to understand environmental factors such as temperature and humidity of their habitat. This study predicted current and future habitat suitability models for understanding the distribution of M. seperata and C. medinalis. Occurrence data, SSPs (Shared Socio-economic Pathways) scenario, and RCP (Representative Concentration Pathway) were applied to MaxEnt (Maximum Entropy), a machine learning model among SDM (Species Distribution Model). As a result, M. seperata and C. medinalis are aggregated on the west and south coasts where they have a host after migration from China. As a result of MaxEnt analysis, the contribution was high in the order of Land-cover data and DEM (Digital Elevation Model). In bioclimatic variables, BIO_4 (Temperature seasonality) was high in M. seperata and BIO_2 (Mean Diurnal Range) was found in C. medinalis. The habitat suitability model predicted that M. seperata and C. medinalis could inhabit most rice paddies.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.123-123
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• 2017

기후변화의 영향으로 개발밀도가 높은 도시지역은 호우로 인한 피해가 지속적으로 증가하고 있다. 최근, 극한 호우에 의해 발생되는 도시침수의 피해를 저감하기 위해 시설물 대책에만 의존하기 보다는 지자체가 수립하는 공간계획을 통해 토지이용, 건축물 등을 아우르는 종합적인 예방전략 마련이 강조되고 있다. 하지만 지자체 도시계획 담당자가 기후변화를 고려해 방재대책을 마련하는데는 국가 차원의 표준화된 방법론의 부재, 침수해석을 위한 전문적 지식이 요구되는 등의 한계가 있다. 본 연구에서는 지자체가 도시계획에 실효성 있는 방재대책을 마련하는데 직접적으로 활용할 수 있는 도시침수에 대한 상세 위험도 주제도를 개발하고자 한다. 이를 위해, 우선적으로 중장기적인 측면에서 기후변화의 영향과 도시지역의 유출 특성을 고려해 방재계획을 수립할 수 있는 강우 시나리오 기준으로 지속시간 1시간에 대한 재현빈도 30년과 100년을 제시하였다. 기후변화의 영향을 고려한 강우 시나리오 기준에 따라 도시지역 내 내수 외수의 침수발생 원인을 고려해 침수심 지도를 생성하고자 한다. 이를 위해 범용적으로 적용할 수 있는 침수해석 모형인 HEC-RAS와 SWMM을 선정하고, 공간적 제약이 없이 폭 넓게 적용할 수 있도록 모형의 구축 절차를 간소화한 방법을 제안하였다. 간소화된 침수해석 모형 결과를 토대로 강우 시나리오별 침수심 지도를 제작하고, 강우 시나리오와 침수심을 기준으로 위험정도에 따라 Red zone, Orange zone, Yellow zone, Green zone으로 영향권을 설정하였다. 실질적으로 각 영향권에 적합한 도시계획 차원에서의 방재대책 수립이 가능하도록 노출특성과 취약성 분석을 실시하였다. 노출특성은 영향권에 노출된 토지이용면적(m2)과 거주인구수(명)로 평가하고 취약성은 영향권 내 취약한 건축물 수(지하 또는 노후 건축물), 보호대상시설물 수로 평가하였다. 침수 발생이 예상되는 영향권별 노출특성과 취약성 분석 결과를 토대로 위험이 높은 지역(Red zone)은 공간규모를 축소해 상세 위험도 공간정보 주제도를 개발하였다. 또한 위험도가 높은 지역은 작은 공간 단위로 노출특성과 취약성을 분석해 상세 위험도 주제도를 개발하였다. 본 연구에서 개발한 상세 위험도 공간정보는 지자체가 도시계획 수립단계에서 실질적인 방재대책을 강구하는데 활용할 수 있을 것으로 기대한다.

• Journal of Korean Society for Geospatial Information Science
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• v.3 no.1 s.5
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• pp.139-150
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• 1995

The assessment/evaluation of land use suitability is an important part of land use planning. In this paper, we developed. The Expert System for a suitability analysis including the function of data storage, analysis, assessment and display by using Borland C++ Language and could suggest the following results in the suitability analysis to select a site for an industrial complex using this system. 1. With the increase in volume and variety of geo-spatial data now available, it has become necessary to find more efficient ways of storing this data. This report presents the Quadtree structure, as a method of gaining significant savings over conventional raster processing in data storage. 2. In order to get the criteria of suitability analysis, the opinions of specialists, administrative officers and citizens were collected by a questionnaire, and used to calculate the weight of geo-spatial data. Also, The Expert System, which we developed, was designed to do overlay and spatial analysis, as well as reflect the various opinions we collected in the questionnaire. The Expert System is expected to be used in other land use planning.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.20 no.3
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• pp.273-282
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• 2002

Although the influence of GIS has been proved in a variety of applications, there also have been some research issues about that the coupling of GIS with other mathematical or engineering tools is necessary to meet various needs of specialized problem domains. Linear Programming, a mathematical technique used in optimal distribution of given quantity, can enhance its usability by integrating with GIS since LP basically does not include means to deal with spatial data. The limitation of the traditional LP technique is that it requires explicitly defined conditions, which is impractical or impossible in such decision making processes as in land use problems that use less crisp decision factors. This study develops a method to incorporate such fuzzy situations by integrating Fuzzy-LP that employs fuzzy logic and GIS. The GIS provides data to or displays data from the Fuzzy-LP processes in the integrated system. This methodology is illustrated to solve a land use distribution problem.

• Land and Housing Review
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• v.2 no.1
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• pp.47-52
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• 2011

Recent advances of technology in materials science have made it easy to respond to user's needs on high performance steel in civil and building structures. The high-performance and high-strength steel are required for large scale structure and high-rise building to have high-strength, high fracture toughness and better weldability etc. Therefore development of 600MPa class steel for mega structure is necessary. high strength steels, however, may have mechanical properties that are significantly different from those of the conventional steels. The application of high-strength steels to building structures should be reviewed as to whether inelastic behavior equivalent to that of conventional steels can be attained or not. This study researched the structural behavior of high strength circular tubes compression and under flexure. Three column tests and three flexural tests were carried out. The suitability of existing design formulae(KBC 2009) and the structural behavior were investigated through these columns and beams with various types.

• Land and Housing Review
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• v.6 no.3
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• pp.147-152
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• 2015

Site coefficient and amplification factor of current domestic Seismic Design Code based on American Seismic Code, have no consideration for the domestic ground condition in which the base rock is normally placed within 30m form the surface. By previous studies, the measured spectral acceleration of the result of dynamic centrifugal test and analysis was smaller than the design spectral acceleration for the period over 1.5 sec. Accordingly, in this study structural analysis and design using dynamic centrifugal test result for pile foundation were achieved, and the quantity of concrete and reinforcement of wall frame was compared with each other. Comparison results of cost using KBC the design spectral acceleration of SC, SD site and SDS, the quantity of reinforcement using SDS for SD site was 17~23% smaller than using the design code SD site.