• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 1992년도 학술논문발표요지
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• pp.27-28
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• 1992

장래 우리나라의 원예시설은 국내외 여건, 경제성장도, 식생활습관 및 농업정책 등에 의하여 그 형태와 규모, 피복재의 종류, 환경조절장치, 배지의 종류 및 사용에너지 등의 변화형태가 다소 차이가 있겠지만, 재배면적, 철골재의 사용, 경질필름이나 경질판의 사용이 증대될 것이며, 환경조절 및 작업의 자동화, 난방용 화석에너지의 대체에너지화가 가속화될 것으로 판단된다. (중략)

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(II)
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• pp.892-897
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• 2002

The research was requested by Meridian Rail Corporation in United States. The Swing Motion Bogie can application by Korea style if synthesize study result of bogie strength evaluation, bogie dynamic characteristics analysis, actual test(maximum speed, derailment coefficient, lateral force, vertical force, vibration acceleration, steady state lateral acceleration) etc..

• Smart Structures and Systems
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• 제15권4호
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• pp.1121-1137
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• 2015

This study presents probabilistic-based damage identification technique for highlighting damage in metallic structures. This technique utilizes distributed piezoelectric transducers to generate and monitor the ultrasonic Lamb wave with narrowband frequency. Diagnostic signals were used to define the scatter signals of different paths. The energy of scatter signals till different times were calculated by taking root mean square of the scatter signals. For each pair of parallel paths an error function based on the energy of scatter signals is introduced. The resultant error function then is used to estimate the probability of the presence of damage in the monitoring area. The presented method with an autofocusing feature is applied to aluminum plates for method verification. The results identified using both simulation and experimental Lamb wave signals at different central frequencies agreed well with the actual situations, demonstrating the potential of the presented algorithm for identification of damage in metallic structures. An obvious merit of the presented technique is that in addition to damages located inside the region between transducers; those who are outside this region can also be monitored without any interpretation of signals. This novelty qualifies this method for online structural health monitoring.

• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 2004년도 춘계학술대회 논문집
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• pp.155-158
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• 2004

• 한국조경학회지
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• 제36권1호
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• pp.38-48
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• 2008

This study examines the characteristics of the herbaceous vegetation structure of Haneul Park District in World Cup Park, which had previously been used as a landfill for 15 years. The survey was carried out through actual vegetation and vegetation structures from 2003 to 2006, biannually. Firstly, as a result of analysis of actual vegetation, the autumn season changed more quickly over the 2 year span than did the spring season in terms of actual vegetation area. Annual plants increased for the initial $3{\sim}4$ years and then perennial plants increased. Secondly, the results of analysis in vegetation structure are as follows: 1. The number of planted species gradually decreased. 2. Miscanthus sinensis var. purpurascens of the control region was maintained but Imperata cylindrica var. koenigii of the non-control region was invaded by Miscanthus sacchariflorus, Glycine soja and Phragmites communis etc. 3. Planted species in the control region were maintained in superior state, but the non-control region was changed by natural occurrence plants until 2006, the fourth year. 4. Physostegia virginiana and Aster koraiensis which were planted in the non-control region were maintained but most of planted species weakened and changed by natural occurrence plants including Erigeron annuus, Artemisia princeps, Setaria faberii and Phragmites communis etc. Based on the results, we suggested the management method of herbaceous vegetation in the Haneul Park District.

• 한국건설관리학회논문집
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• 제7권5호
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• pp.167-176
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• 2006

현재 재건축사업은 추진 의사결정과 관련한 확정된 지표나 기준이 없이 막연한 수익성에 대한 기대를 토대로 시행되고 있으며, 사업시행과정 에서 직면하게 되는 제반 위험 에 대해 경험 적으로 대응하고 있는 실정이다. 또한 재건축조합이나 시공예정 회사들이 제공하는 관리처분계획에 포함된 수익성에 관한 정보는 결정론적 분석을 통한 단순한 예측에 불과하여 재건축을 시행하는 과정에서 결과가 수정되는 것이 일반적이다. 즉 수익성에 대한 예측이 재건축시행 과정상의 유동적인 상황에서 변경됨에 따라 예측결과에 대한 신뢰도는 근본적으로 내 외적인 한계를 갖고 있다. 본 연구는 재건축사업의 수익성에 영향을 미치는 변수들을 확률적으로 평가하여 수익과 위험을 동시에 분석하는 수익성예측모델을 개발하고, 사례연구를 통해 개발모델의 적합성을 검증하여 기존의 결정론적 접근방식이 갖는 한계를 극복하고자 한다.

• 한국해양공학회지
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• 제18권2호
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• pp.52-57
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• 2004

Preflex beam is a method of construction designed to hold the pre-compressive stresses over the concrete pier by the preflexion load. During the fabrication of the girder, welding causes residual stresses. The welding residual stresses must be relieved in order to generate the accurate compressive pre-stresses. In this study, to determine the thermal distribution characteristics on the girder by welding, both three-dimensional finite element analysis and two-dimensional finite element analysis, in a quasi-steady state, is carried out. After comparing each result between the three-dimensional analysis and the two-dimensional analysis, finite element analysis is carried out against the actual girder, and the welding thermal distribution characteristic over the preflex beam is analyzed. It is possible to provide the input data for the analysis of the welding residual stresses.

• 대한전기학회논문지
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• 제39권6호
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• pp.557-567
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• 1990

This paper describes the static and dynamic characteristic analysis of the Series Resonant DC to DC Converter with frequency control. The natural commutation of all switch element is realized when the switching frequency is below the resonant frequency of the tank circuit, and the analysis is limited to only this region. For the analysis method, state plane technique is adopted, and each operation mode is defined from normalized switching frequency Fsn. Under this condition, circuit performance is analyzed ideally. The physical characteristics of the series resonant converter is easily grasped by this analysis method with frequency control and this analytical results are directly applicable to the actual converter design. The validity of the analysis is verified by comparing with experimental results and the stability of the converter is confirmed against small variations around the operating point by conventional frequency domain analysis.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3253-3256
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• 2013

Lithium is a highly attractive material for high-energy-concentration batteries, since it has low weight and high potential. Rechargeable lithium-ion batteries (LIBs), which have the extremely high gravimetric and volumetric energy densities, are currently the most preferable power sources for future electric vehicles and various portable electronic devices. In order to improve the efficiency and lifetime, new electrode compounds for lithium intercalation or insertion have been investigated for rechargeable batteries. Solid-state nuclear magnetic resonance (NMR) is a very useful tool to investigate the structural changes in electrode materials in actual working lithium-ion batteries. To detect the in-situ microstructural changes of electrode and electrolyte materials, $^7Li-^{19}F$ double-resonance solid-state NMR probe with a static solenoidal coil for a 600-MHz narrow-bore magnet was designed, constructed, and tested successfully.

• 정보관리학회지
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• 제25권3호
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• pp.297-320
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• 2008

시대적으로 역사적 기록물과 지역의 향토자료가 중요하게 부각되고 있다. 향토자료의 수집과 체계적인 관리가 절실한 상황에서 현재 수집된 자료들이 어떻게 관리되고 있는지에 대한 연구가 필요하다. 이 글의 목적은 향토자료를 생산하고 관리하는 지방문화원의 향토자료 관리 실태를 조사하고 분석하여, 그 결과 나타난 문제점을 토대로 바람직한 향토자료 관리를 위한 대안을 제시하고자 하였다. 그 결과, 지방문화원에서 향토자료 관리는 열악한 인력과 재정적인 문제로 향토자료의 체계적인 자료수집과 관리가 이루어지지 못하고 있다. 또한 지자체의 향토자료의 인식의 정도가 달라 문화원마다 향토자료 관리정도의 편차가 심하며, 문화원의 발간사업이 지역민의 생활보다는 지역 권력사에 치중되어 풍부한 지역사를 담지 못하거나 이를 교육과 문화콘텐츠 제작에 제대로 활용하지 못하는 것으로 나타났다.