• Journal of Korean Association for Spatial Structures
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• v.5 no.4 s.18
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• pp.79-90
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• 2005

The purpose of this study is development of a finite element algorithm to find out the stressed condition, slipped direction and slipped dimension when some elements of cable-membrane structures are slipped from it's initially designed coordinates by external loads as wind or non uniform load and so on. In order to search the slipped behaviors of cable-membrane structures, a Arbitrarily-Lagrangian-Eulerian(ALE) finite element formulation is introduced. In these procedures, a stiffness matrix related with ALE concept is formulated and a FE analysis program for cable-membrane structures with slipped elements is developed. Various examples for cable and membrane structures are presented to verify the program's validation. The results are shown good agreement with that of existed one.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2023.11a
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• pp.230-233
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• 2023

우리 헌법은 인간의 존엄과 가치 그리고 행복을 추구할 권리를 보장하고 있으며, 편의증진법과 교통약자법을 통해 장애인등이 교통수단, 여객시설 및 도로 등을 비장애인들과 차별 없이 이용하여 이동하고, 도로와 대중교통수단, 공공 건축물과 주거 등 생활 필수시설에 자유롭게 접근하기 위한 접근권을 보장하고 있다. 우리나라는 이동권의 보장을 편의시설 제도라는 독자적인 체계를 통해 이루어지고 있으며, 이를 실질적으로 보장하기 위하여 장애물 없는 환경 인증 제도(BF 인증제도)를 도입하였다. 시행 15년을 맞은 BF 인증제도는 양적으로는 많은 발전을 가져왔지만, 질적으로 특정 건축물 등 일부에 대한 인증 편중 현상이 있으며 안전취약계층에 대한 재해 안전확보에 대한 고려가 포함되지 않아 부진정한 이동성과 접근성의 보장이라는 한계를 가지고 있다. 이동권 보장이 얼마나 잘 이루어지느냐는 그 나라의 사회 안전망이 얼마나 잘 갖추어져 있는지 판단하는 척도라 할 것이며, 따라서 이러한 이동권 보장은 위험상태에서의 안전한 피난을 함축하고 있으며 중첩적으로 국가의 기본권 보호 의무의 이행과 관련된다. 이에 따라 이동권과 접근권의 증진을 위한 BF 인증 규정을 안전 규범으로 보완하여 장애인과 비장애인이 사회의 일원으로서 평등한 인격적 주체로 공동체에 기여하는 안전한 사회적 환경의 조성이 긴절히 요청된다고 할 수 있다.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11b
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• pp.643-646
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• 2003

이 논문은 작업 대상물(object)을 최소 시간으로 interception 하기 위한 방법에 대하여 기술한다. 목표는 로봇이 world coordinate system을 기준으로 x축으로 이동하는 컨베이어 라인 상에서 이동되는 작업 대상물을 intercept 하는 것이다. 컨베이어 시스템이 최소의 시간으로 작업 대상물을 intercept하기 위해서는 다음의 주요 계획이 필요하다. 첫째는 최적의 object과 end effector의 meeting point 선택, 두 번째는 첫 번째 계획이 실효를 이루기 위한 로봇의 trajectory선택이다. 두 가지의 계획 중 여기서는 두 번째 계획이 최적이라고 가정하고 첫 번째 계획법 즉, 컨베이어 시스템 로봇을 이용한 작업 대상물의 gripping 동작을 행함에 있어서 최소 시간으로 작업대상물을 gripping 하기 위한 컨베이어 시스템과 minimum time gripping 알고리즘이 제시된다.

• Journal of Korean Society on Water Environment
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• v.29 no.4
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• pp.489-496
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• 2013

Ground water underlying soil is vulnerable to pollution by organic chemicals through their percolation through the soil system. This study was conducted to provide information on the seepage behavior of organic chemical contaminants in clay, silty and sandy soils. Chloroform, 1,1,1-trichloroethane and trichloroethylene are readily transported through the soil; their percolated mass were 4.6-19.2 percent of the total mass applied. Tetrachloroethylene, 1,2-dichlorobenzene and 1,3-dichlorobenzene were retarded by soils due to sorption. Between 0.6 and 4.8 percent of the material applied to the surface percolated within the experimental period. Carbon tetrachloride was attenuated considerably by passage through soils. Only 0.1-0.4 percent of the mass reached the groundwater. Significant degradation of bromoform was observed. Apparent breakdown of intermediates of the brominated compounds were detected. Transformations of the brominated compounds appear to be the result of both biological and chemical processes. The effect of soil type on the mobility of organic chemical contaminants was considerable. The organic contaminants moved faster in sandy soil than in either clay or silty soils.

• Economic and Environmental Geology
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• v.37 no.3
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• pp.311-324
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• 2004

We investigated the contamination and behavior of heavy metals in stream sediments within the watershed of Juam Reservoir. Many abandoned mines within the reservoir can act as a potential contaminant source for water quality. Heavy metal concentrations (Cr, Cu, Ni, Pb and Zn) in stream sediments from watershed are very low, indicating that content of heavy metals in the sediments probably do not affect the water quality in Juam Reservoir. However Pb concentration in the stream sediments increases downward streams, suggesting the possible diffusion of Pb contamination. According to the leaching ratio for stream sediments at a strong acidic condition in the abandoned mine areas, the relative mobility for metals decreases in the order of Pb＞Zn=Cu＞Ni＞Cr, indicating that Pb can have a bad effect upon the water quality in Jum Reservoir. Moreover, if contaminated sediment is placed in the bottom of reservoir (i.e., reducing condition), the relative mobility of Pb is the highest, indicating that Pb in the bottom sediments can be leached to water at interface between water and sediment with changing in physicochemical conditions.

• Journal of Software Assessment and Valuation
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• v.15 no.2
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• pp.51-57
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• 2019

On increasing illegal software copyright, the need for similarity analysis is now rising. The reliability of object material are becoming important when it's moving from developer to evaluation experts. Object material as a comparison data, is the important data to the evaluation expert which is delivered from agencies such as courts and police stations. The object material is submitted at first to the Copyright Commission and then delivered to the evaluation expert with safe. However, if the similarity result is not satisfied to the both side, they will claim to the reliability of the object material such as source code modification or revision etc. Software objects is produced in a file format and are recognized as being able to be modified. Therefore, the reliability to the object material is studied in various ways, and a forensic is proposed as one method. This study showed the suggestion to keep reliability of the object material through the actual evaluation cases.

• Korean Journal of Crystallography
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• v.5 no.1
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• pp.39-50
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• 1994

Diamond thin films were deposited on silicon, molybdebum, titanum and tugsten substrates, and were chlwntnizen using scanning electron microscopy, X-ray diffraction analysis and Raman spectroscopy. From the result of experiment in various deposition periods, it was found that found that were nucleated and grown on interlayed carbide layers, which were formed on refractory metal substrates at the initial stage of.

• Elastomers and Composites
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• v.44 no.4
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• pp.397-400
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• 2009

Ozone caused the crack on the surface of a rubber article by oxidation of double bond at room temperature. Wax migrates to the surface of a rubber article and makes a physical barrier to prevent process of ozonation. We investigated change of molecular weight distribution of waxes in unfilled NR, SBR, and BR vulcanizates before and after aging at room temperature for 6 months. Migration and evaporation behaviors of wax in a rubber article at ambient conditions help understand a role of wax as an antidegradant and appearance contamination of a rubber article. The relative intensity distribution of n-alkanes of the NR specimen after the aging was shifted to higher molecular weight compared with the relative intensity distribution before the aging, while those of the SBR specimen before and after the aging did not show a big difference.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.4
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• pp.247-256
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• 2002

Distribution of surface and suspended sediments was studied to understand sedimentary processes of finegrained sediment near the cooling water intake of Pyongtaek power plant on the west coast of Korea. The grainsize of surface sediment during the winter was coarser in the opened northern area than sheltered southern area. During the summer, finer sediment was found in the east (landward) than west due under dominantly the influence of tidal current. The concentration of suspended sediments was higher in the winter than summer and in the mid- to deep waters than surface waters. Asymmetry of tidal current induced net landward transport of suspended sediments. Landward transport of suspended sediments was most significant at the beginning of flood time when water level is low. Net suspended sediment fluxes ranged from 3.4$\times$10$^{-3}$ kg.m$^{-2}$ .s$^{-1}$ to 5.7$\times$10$^{-3}$ kg.m$^{-2}$ .s$^{-1}$ This large landward transport of suspended sediments is attributable to combination of enhanced flow induced by intake of cooling water and artificial structures near the water intake.

• Water for future
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• v.32 no.3
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• pp.104-108
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• 1999