• Journal of the Korea Institute of Building Construction
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• v.11 no.3
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• pp.301-309
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• 2011

Apartment housings that adopt a bearing wall structure design, which account for a majority of the housing units available in Korea, are not free from structural constraints that limit the extension of their service life. The resulting need for reconstruction from the ground up requires a massive consumption of resources and energy, and triggers environmental pollution resulting from construction wastes. As a solution to such issues, the government enforces incentive schemes to promote a remodeling-friendly rahmen structure design. Green Frame, which is a novel concept of composite precast concrete structure to support rahmen structure apartment housing buildings, can address the constraints of bearing wall structure and conventional rahmen structure designs that limit the potential for remodeling projects, while reducing the term of construction. Therefore, this study aims to analyze the characteristics of Green Frame and its absolute term of construction, and compare the terms of frame work construction in apartment housing projects adopting different structural design approaches to illuminate their differences. In the end, Green Frame is found to be capable of reducing the term of construction in apartment housing projects. As the term of construction is a very critical element of a construction project, Green Frame will ultimately prove to be one of the key enablers to ensure the success of apartment housing construction projects.

• Explosives and Blasting
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• v.28 no.2
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• pp.99-107
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• 2010

Domestic explosive demolition techniques have been developed and applied for low-rise structures up to now. However, the demand for the development of those techniques that can be applied economically, safely and environment-friendly rapidly increases because the old high-rise RC rahmen structures that were built since around 1970s are now required to rebuild. As a result, element technologies of explosive demolition for low-rise structures were applied to take advantage of technology in high-rise structures that performed application testing at Chungang Department demolition field in Daejeon city. It could judge elements technology establishment for high-rise structure demolition and field application and suggest the improvements when the problems occurred to develop High-rise building demolition techniques for method of protection a field test and the dust reduction test. The water cannon test was applied to reduce the dust site and the drilling tests are performed to select the best components for explosives demolition elements techniques of the reliability. This paper shows that we have the ability to remove a high-rise building using environmentally friendly safe and economical explosives demolition method. It would contribute to prevent a foreign company from entering the domestic market and should contribute to acquire competitiveness of domestic demolition industry.

• Journal of Bio-Environment Control
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• v.20 no.1
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• pp.50-57
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• 2011

This study investigates the structural safety of typical greenhouse to be utilized for developing plant factory. New long-span greenhouse systems were presented according to the results of structural analyses performed by finite-element program, ABAQUS. Reasonable values of design loads such as wind and snow loads in the Greenhouse Design Specifications (1995) were applied to check the new greenhouse systems. It was concluded that the new greenhouse systems were consistently safe enough to resist to both wind load and snow load. The new greenhouse system can be used to make simple and economic plant factory.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.250-256
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• 1996

In order to estimate production cost of rice per ha of large farm, a detail survey of 104ha farm was made in 1994. Amount of labor input and labor cost per ha was calculated as 270, 000won and 108hours. Direct production cost of the farm was 1, 092, 000won(l00) and was lower than that of average farms 2, 067, 000won(189) in Korea. But it still was higher than that of Sac1amento farms 717, 000won(66) and that of Buter Area's, 845, 000won(77). It seems feasible to cut down the cost about 10~15% provided the labor and machinery may be used more efficiently. Some cost down may also be possible on marketing and processing sectors. Therefore it may not be pessimistic in competing with U.S. rice farms if we establish 100ha size well managed and arranged farms in Korea.

• Journal of the Korea Concrete Institute
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• v.24 no.3
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• pp.249-258
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• 2012

Integral and rigid frame bridges have advantages in bridge maintenance and structural efficiency by eliminating expansion joints and bridge supports. However, the detail of typical girder-abutment connection is rather complex and increases construction cost depending on construction detail. For the purpose of compensating disadvantages such as complexity and additional cost, a new type of bridge is proposed in this study, which improves the efficiency of construction by simplifying the construction detail of girder-abutment connection. The proposed bridge has the connection detail of steel girder and abutment integrated by prestressed PS bar installed in the connection. In this study, finite element analysis and fatigue load test are conducted to evaluate the fatigue capacity of the proposed girder-abutment connection. The results of the finite element analysis revealed that the possibility of the fatigue damage in the girder-abutment connection is very low. The results of the fatigue load test verified that the integrity of the girder and abutment connection is maintained after 2,000,000 cycles of fatigue loading.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.10a
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• pp.348-355
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• 2000

The characteristics on non linear behavior and the failure mechanism of RC space frame structure serving railway under seismic action have been investigated by numerical analysis in time domain. The structure concerned is modeled in 3 dimensional extent and RC frame elements with fibers are employed. Fibers are characterized as RC one and PL one to distinguish different energy release after cracking. Due to deviation of mass center and stiffness center of entire structure the complex behavior under seismic action is shown. The excessive shear force is concentrated on the pier beside flexible one relatively, which leads to failure of bridge concerned.

• JOURNAL OF ELECTRICAL WORLD
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• no.6 s.30
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• pp.45-52
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• 1979

서독은 에너지면에서 있어서, 석탄 이외는 국내자원이 부족하며, 중화학공업이 발달한 결과 석유에 대한 의존도가 높아져 에너지의 해외의존도가 급상승하고 있으며, 에너지수요의 안정화를 위해 원자력개발을 강력하게 추진하고 있는 등. 이런 사정으로 말미암아 에너지 연구개발에 가장 열심인 나라의 하나이다. 즉 석유 위기 직후에 에너지 연구 개발 전체계획(즉 ${\ulcorner}$라멘프로그램${\lrcorner}$)을 책정하고 종래부터 강력하게 추진하여 온 원자력 연구 개발에 덧붙이어 태양에너지, 풍력에너지, 석탄가스화${\cdot}$액화 등의 비핵에너지 연구 개발을 종합적으로 개시하고 있는 것이다. 본호에서는 1977년 4월에 책정된 에너지 연구 개발 종합계획$(1977{\~}80)$을 중심으로 서독의 에너지 연구 개발을 살펴보기로 한다.

• Proceedings of the Korea Concrete Institute Conference
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• 1993.04a
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• pp.207-212
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• 1993

Rail carrying structures in international routes as well as domestic ones shall be designed to carry HL(High Speed Railway live Load) loads, The loads shall be placed in the most unfavourable position for the part of the structure in question. In general, influence lines may be used to determine the maximum bending moments and maximum shear forces in the reinforced concrete rahmen bridge structures. In this study, based on the finite element analysis, equivalent distributed loads of HL loading for design of the rahmen bridges are deterimined.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.309-314
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• 2000

Stress concentration at haunches of Rahmen bridges was evaluated by means of FEM analysis. The selected haunches were of three different types; straight, skew and curved ones with$55^{\circ}$of angle respectively. The result showed that the effect of stress distribution was the lowest at the curved haunch and the highest at the straight one. Such a result could be used to provide some guidelines for revising related standard specifications.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.239-241
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• 2005

Reliability analysis of the design of reinforced concrete rahmen bridge is performed. Statistical properties for loads and resistances are taken into account in the analysis and the reliability indices are calculated for strength limit state of the current bridge design specification. Results are presented and discussed for different span lengths and wall heights.