• Geotechnical Engineering
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• v.5 no.2
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• pp.45-56
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• 1989

The influence of stress path on the deformation characteristics of clay has been studied through a series of stress-path controlled triaxial tests on artificially sedimented and normally con- solidated Kaolinite. It has been found that there exists a critical stress increment ratio, Kc, in which stress·strain characteristics possesses a linear relationships and beyond Kc, strain hardening. A modified hyperbolic constitutive model for the strain hardening behavior has been formulated based on the Drnevich's hyperbolic function. And, a method of settlement analyses has been Proposed wherein the effect of stress path during consolidation is taken into account.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.2
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• pp.177-189
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• 1992

This paper aims at developing a finite element program to predict undrained behavior of granular soil by using elasto-plastic constitutive model. A computer program developed by authors based on Christian's techniques for undrained behaviour of the soil has been employed coupled with Lade's single work-hardening model. Modification of the program for drained behaviour, considering restraint of volumetric strain, makes it possible to analize the underained behaviour. To validate the newly developed program, comparison of results was performed between numerical values and experimental data for Baekma river sand as well as Sacrmento river sand studied by Seed and Lee. The program is evaluated to have high accuracy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.3
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• pp.69-78
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• 1993

A testing system has been developed to evaluate the seasonal variation of the resilient modulus of granular subgrade soils. Two sites were successfully instrumented with soil moisture-temperature cells to monitor over a period of one year, the field temperature and moisture content underneath the pavement. Multiple regression equations were developed to determine the resilient modulus under environmental conditions. It is noted that the use of the effective resilient modulus at the location of the Average Depth of Significant Stress (ADSS) provides a reasonable basis for determining subgrade properties. In addition, a theoretical model has been developed to predict the resilient modulus due to the change of temperature and moisture condition.

• Spatial Information Research
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• v.5 no.2
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• pp.177-183
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• 1997

S1he concept of a class in the land-use classification system can be equally applied to a class in the land-use-change classification. The maximum likelihood method using linear discriminant function and Markov transition matrix method were integrated to a synthetic modeling effort in order to project spatial allocation of land-use-change and quantitative assignment of that prediction as a whole. The algorithm of both the multivariate discriminant function and the Markov chain matrix were discussed and the test of synthetic model on the study area was resulted in the projection of '90 year as well as '95 year land -use classification. The accuracy and the issue of modeling improvement were discussed eventually.

• The Journal of Engineering Geology
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• v.12 no.4
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• pp.459-469
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• 2002

We have remolded marine clay sample collected along the vertical and horizontal directions and investigated the characteristics of the consolidation constants by SCT and CRSC methods. We have studied also on consolidation chracteristics and application for weathered granite soil using SCT and CRSC methods for undisturbed and disturbed samples. As the result, values of pre-consolidation stress, compression index, excessive pore pressure, pore water pressure ratio of the marine-clay were different due to different test methods(SCT and CRSC) and sampling directions(vortical and horizontal directions). Disturbed and undisturbed samples of the weathered granite soil have showed similar change aspect like marine clay during over-consolidatied and normally consolidatied stages.

• 한국정보교육학회:학술대회논문집
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• 2004.08a
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• pp.633-639
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• 2004

본 연구는 웹의 비동기적 상호작용의 하나인 게시판의 교육적 효과에 대해 연구하는데 있다. 전자게시판의 활용은 주로 학생 상호간의 의사소통 수단으로 활용되어 왔다. 본 논문은 교사의 개입이 없는 방임형 게시판과 교사가 직접 개입하는 교사 개입형 게시판의 의사소통 능력과 상호작용의 질적 수준을 학습효과라는 관점에서 분석한다. 내용 분석을 위한 적절한 도구를 고안하고 교사 개입의 방법과 수준 등에 대한 논의를 한다.

• Proceedings of the Korea Society of Design Studies Conference
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• 1999.05a
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• pp.18-19
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• 1999

우리나라는 그동안 세계가 놀랄만큼 빠른 경제발전을 이룩하였는데 그렇게 된데에는 무엇보다도 교육을 통해서 싸고 질좋은 노동력을 확보할 수 있었기 때문이라고 보아진다. 그런데 다가오는 21C의 변화는 인류사회의 관심이 산업 사회적특징에서 정보 사회적특징으로 전환되고, 가치관과 지식관도 근대 사회적 기준에서 초근대 사회적 기준으로 바뀌면서 새로운 전환기를 맞이하는 디자인 교육에도 많은 영향을 주고 있다.(중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.11a
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• pp.20-32
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• 2001

국내의 원예산업은 대규모 온실의 설립과 이를 이용한 시설원예작물의 생산을 통해 재배농가의 소득을 증대시키기 위하여 많은 시설투자가 이루어지고 있고, 온실산업이 발달함에 따라 플러그 및 분화 등 용기재배를 통한 생산량도 급격히 증가하고 있다(농촌진흥청, 1995). 이러한 추세를 반영하듯 국내에는 여러 중소업체가 상토를 생산 및 시판하고 있으나, 재배농가 쪽에서는 어떤 회사에서 제조된 상토를 작물재배에 이용해야 할지, 또는 어떤 업체에서 시판하고 있는 상토가 내가 재배하는 작물에 적합한지에 관한 확신이 없는 상태에서 상토를 구매하여 작물재배에 이용하고 있는 상황이다. (중략)

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.5 no.4
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• pp.414-426
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• 1993

A description is given of the recent techniques employed for the measurement of currents in the East China Sea continental shell The variability of the currents in the region is briefly discussed as it affects the measurement Data sources have been collated to develop an inventory of current observations in the shelf seas around Korea.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.11a
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• pp.341-346
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• 2002

우리나라의 남해안은 양식업에 의한 어업 활동이 활발하다. 특히 굴양식은 남해안 주민의 주소득원으로 생산량이 급격히 증가하고 있으나, 굴패각 형태의 폐기물 또한 급격히 증가하여 폐기물로 처리하여야 하는 굴패각의 처리비용의 부담으로 방치되거나 무단 투기됨으로 인해 해안 지역의 환경 오염이 날로 심각해지고 있다. 지금까지 굴패각의 처리는 매립에 의존하였으나 보다 확실한 처리 방법을 찾기 위해 많은 연구가 이루어지고 있다.(중략)