• Journal of the Korean Geotechnical Society
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• 제22권2호
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• pp.19-28
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• 2006

Long-term field observations were performed in three excavation sites in order to investigate the displacement behavior of adjacent ground during overall excavation procedure, where the depths of deep excavations were 15 m$\∼$29 m. In this study, ground settlements and lateral displacements of braced wall measured during installation of retaining wall and removal of bracing were specially focused to evaluate the behavior quantitatively according to three-stage-divided procedure, i.e. pre-excavation, main excavation, and removal of bracing. Through field measurements on three excavation sites, lateral displacements induced during removal of bracing are approximate to 40$\%$ of the amount found during main excavation stage and additional adjacent ground deformation during post-excavation procedure ranges from 18$\%$ to 33$\%$ of that found during main excavation stage, based on the settlement volume. In conclusion, it was quantitatively identified in this study that the deformations of adjacent ground during pre- and post-excavation stage were not negligible.

• Explosives and Blasting
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• 제27권1호
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• pp.62-78
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• 2009

Recently, construction techniques have been rapidly developed with reconstruction of old buildings, urban regeneration and efforts of restoring natural ecology, so demolition of deteriorated buildings has been rapidly increasing. Demolition work of building should be executed without damaging surrounding environments according to relevant regulations. There are various demolition methods and among them, explosives demolition is the most practical way for expenses and safety of work. As a part of Daejeon stream ecological restoration project, this thesis is a case of executing demolition of Chung-Ang Department Store which was built 35 years ago as covered structure on the upper part of Daejeon stream with explosives demolition. This structure is 8 stories high, total height of 41.6 m including basement floor, $1,650m^2$ for building area and $18,351m^2$ for total floor area. It is located in the center of Daejeon city where shopping centers and buildings are crowded and main facilities are Daejeon subway (18m), backside shopping center (20m), underground shopping center(15m), Mokchuk bridge, Eunjung bridge(0.25m) and fiber-optic cable(0.25m). In this project, implosion was selected for explosives demolition methods by considering this area being a busy urban area, and this project was executed after examining collapse movement of structure in advance using simulation program not to damage main facilities. Total 80kg of explosives and 1,000 detonators were being used. This project will be a good case of executing explosives demolition successfully by applying implosion on urban area in the country.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 한국항해항만학회 2013년도 춘계학술대회
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• pp.563-565
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• 2013

해양플랜트 구난기술은 상당 부분 선박구난과 동일하여 수중절단, 인양, 계류, 기름의 이송 및 예인 등은 공통적으로 적용이 가능하다. 그러나 구조물이 복잡하고 대형이며, 심해 설치 등의 특성이 있으므로 해양플랜트 구난작업에는 유형별 구조에 대한 정확한 이해가 필요하다. 해양플랜트 설치, 이송 및 해체 분야에 대한 기술은 구난 분야에도 적용이 가능하므로 해양플랜트 특성에 적합한 구난기술 개발 방향을 제안하였다.

• Journal of Digital Convergence
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• 제13권4호
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• pp.303-310
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• 2015

Game technologies are now applied in various engineering areas such as the simulation of surgical operation or the implementation of a cyber model house. One of the essential and important technology in these applications is cutting of the 3D polygon model in real time. Real-time cutting technology is an essential technology needed to implement the simulation of a building demolition or a car assembly for training or educational purpose. Previous cutting method using the conventional BSP-Tree structure has some limitations in that they divide the whole world including the 3D model and its environment, only into two parts with respect to an infinite plane. In this paper, we show a technique cutting the 3D model in a finite extent in order to solve this problem. Specifically, we restricted the cut surface in a finite rectangular area and constructed the mesh for the divided surface. To show the usefulness of our partial cutting technique, an example of the dismantling process simulation of a nuclear reactor polygon model was illustrated.

• The Journal of the Convergence on Culture Technology
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• 제8권5호
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• pp.469-475
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• 2022

As the recent structure construction is constructed as a large-scale and deep underground excavation in close proximity to the building, the installation of retaining wall and supporters (Struts) has become complicated, and the number of supporters to avoid interference of the structural slab has increased. This construction process becomes a factor that causes an increase in construction joints of a structure, leakage and an increase in wall cracks. In addition, this reduced the durability and workability of the structure and led to an increase in the construction period. This study planned to dismantle the two struts simultaneously as a plan to reduce the construction joints, and corrected the earth pressure by assuming the reaction force value by the initial earth pressure and the measured data as the response ratio. After recalculating the corrected earth pressure through the iterative trial method, it was verified by numerical analysis that simultaneous disassembly of the two struts was possible. As a result of numerical analysis applying the final corrected earth pressure, the measured value for the design reaction force was found to be up to 197%. It was analyzed that this was due to the effect of grouting on the ground and some underestimation of the ground characteristics during design. Based on the result of calculating the corrected earth pressure in consideration of the response ratio performed in this study, it was proved analytically that the improvement of the brace dismantling process is possible. In addition, it was considered that the overall construction period could be shortened by reducing cracks due to leakage and improving workability by reducing construction joints. However, to apply the proposed method of this study, it is judged that sufficient estimations are necessary as there are differences in ground conditions, temporary facilities, and reinforcement methods for each site.

• Clean Technology
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• 제18권4호
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• pp.373-378
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• 2012

The end-of-life vehicles (ELV) are important recycling sources, and there are several stages involved in the recycling such as dismantling, shredding, and treatment of shredder residues (ASR). The legal recycling rate should be at least 95% on and after 2015, while we need a proper system to monitor recycling of ELV components and to calculate the practical recycling rate. The paper suggests a monitoring system that calculates practical recycling rates of dismantled components by use of a database of standard recycling rate as well as a web-based monitoring, which is linked to the Eco Assurance system for electric & electronic equipment and vehicle (EcoAS). Also the system supports dismantling and monitoring process by incorporating a standard vehicular component database, which facilitates recording dismantled weight data but also monitoring of dismantled components.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1244-1247
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• 2004

In the last year, the number of registered vehicles in Korea surpassed the 14 million mark, and increase in number continuously. Nowdays, this tendency has raised some problems inevitably in the view of expansion of ELV and earth environment pollution resulted from it. Currently, the domestic recycle rate of ELV is about 75％. the reason of the row rate of it is due to that dismantling company can not obtain the needed recycling technology. State of art for recycling technology of ELV in domestic & foreign was introduced.

• Proceedings of the KIEE Conference
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• 대한전기학회 2004년도 추계학술대회 논문집 전기설비전문위원
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• pp.53-55
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• 2004

부분방전 검출을 이용한 XLPE 케이블 진단은 중간 및 종단 접속재의 계면에 존재하는 결합을 검출할 수 있는 가장 효과적인 방법으로 제시되고 있지만 현장의 큰 노이즈로 인하여 신뢰성 있는 진단이 쉽지 않다. 하지만 국내에서 많은 연구가 이루어진 송전케이블 진단 기술을 바탕으로 배전케이블 진단에 적용하여 종단접속부에서 발생된 부분방전을 성공적으로 검출하였고 해체 조사를 통하여 결함을 검출하였다. 본 논문은 참고문헌[1]에 발표한 논문에 연결되는 논문으로 전편은 2004년 2월 부분방전 검출사례를 보고한 논문이고 본 논문에서는 8월 계획정전을 통하여 문제된 접속함을 교체한 후 해체조사를 통하여 결함을 검출한 사례보고이다.

• Journal of Korea Foundry Society
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• 제4권2호
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• pp.134-139
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• 1984

25% 크롬주철의 제조에 필요한 중요사항을 실험한 결과 다음 결론을 얻었다. 1) Sound 한 제품을 얻기 위하여는 Riser의 Modulus 가 제품 Modulus에 대해 1.1 배 이상이어야 한다. 2) 선수축율은 측정 결과 18/1,000 이었으며, 3) 주입온도는 $1440^{\circ}C\;{\sim}\;1460^{\circ}C$가 적당하며 후육제품은 가급적 낮은 쪽으로 박육제품은 높은 쪽으로 주입온도를 선택하는 것이 바람직하다. 4) 형상이 단순한 제품은 상온에서 해체할 수 있으나 형상이 복잡한 제품은 $500^{\circ}C\;{\sim}\;400^{\circ}C$ 사이에서 해체한 후 로에 장입 로냉하므로 Crack발생을 피할 수 있다. 5) 본 실험에서 주형 재료의 효과는 Chromite Sand에 Zircon Base의 도형재의 적용이 가장 효과적 이었으나 Silica Sand 적용으로도 미려한 표면을 얻을 수 있었다.

• Defense and Technology
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• 1호통권203호
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• pp.42-55
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• 1996

미국을 비롯한 선진 7개국에 의해 '87년 4월에 미사일 관련 부품 및 기술에 대하여 수출 통제가 합의된 이후, 지금까지 MTCR에 가입한 회원국은 25개국에 이르며, 비회원국중에서도 주요 미사일 수출국들은 MTCR지침을 준수하겠다고 약속하였다. 이에 정부는 구 COCOM 해체 후 급변하는 세계 정세 및 산업 고도화를 고려함과 동시에 국제적 지위 향상을 위해 미사일 비확산 체제의 회원국에 가입하고자 현재 추진중에 있다. 국내의 미사일 관련 전략 물자 수출 통제 제도를 원활히 운영해 나가기 위해서는 MTCR의 역사적 배경, 국제 활동 및 현안 문제점, 그리고 향후 예상되는 발전 과정을 이해하는 것이 중요하다고 생각한다. 따라서 이 글에서는 MTCR과 관련된 내용들의 문헌을 정리 요약하여 소개한다.