• 한국지진공학회논문집
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• 제24권4호
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• pp.157-167
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• 2020

In this study, a field bridge test was conducted to find the dynamic properties of cable supported bridges with resilient-friction base isolation systems (R-FBI). Various ambient vibration tests were performed to estimate dynamic properties of a test bridge using trucks in a non-transportation state before opening of the bridge and by ordinary traffic loadings about one year later after opening of the bridge. The dynamic properties found from the results of the tests were compared with an analysis model. From the result of the ambient vibration tests of the cable supported bridge with R-FBI, it was confirmed that the dynamic properties were sensitive to the stiffness of the R-FBI in the bridge, and the seismic analysis model of the test bridge using the effective stiffness of the R-FBI was insufficient for reflecting the dynamic behavior of the bridge. In the case of cable supported bridges, the seismic design must follow the "Korean Highway Bridge Design Code (Limit State Design) for Cable supported bridges." Therefore, in order to reflect the actual behavior characteristics of the R-FBI installed on cable-supported bridges, an improved seismic design procedure should be proposed.

• 한국연안방재학회지
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• 제5권4호
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• pp.173-182
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• 2018

As the research about increasing the efficiency of dredging soil transport, the technology, which reduce the friction between pipe wall and fluid in the pipe and disturbed generating pipe blockage, has been developed. So for the purpose of applying this technology to real construction site, main test has been tried at the real scale test in field. As a test result, this paper will show 30% flow efficiency increasing by permitted electro magnetic force to the pipe. And test result was evaluated as a ultra sonic velocity profiler. To propose the design technique and the execution manual of the high efficiency dredging material transport technic, this research have confirmed flow status changing depending on a soil material kind under electro-magnetic field and analyze the effect of electro-magnetic field which affects to each dredged soil material transportation. For achieving this research, EMF(Electro-Magnetic Field) generator is installed on the dredger(20,000HP) and through monitored flow status, dredging soil flow rate and sampled material specification is confirmed. Also dredger operating condition is measured and dredger power for soil transportation, hydraulic gradient and flow rate are compared, as transportation efficiency is calculated by this parameter, it is possible to check transportation efficiency improvement depending on each dredged soil material under electro-magnetic field. To verify the technique of dredged soil transfer using electromagnetic field, which is the core technique of the high efficiency dredged soil transfer, and the technique of expert system for pipeline transfer and the flow state. This could lead to a verification of transfer efficiency according to the characteristics of the dredged soil (sand, clay, silt) and the transfer distance (5km, 10km, 15km), which is planned to be used for a technology development of pump power reduction and long-distance transfer applying the high efficiency dredged soil transfer technology.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.230-233
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• 2008

Stainless steels are alloy steels with iron as the primary constituent and chromium, nickel, and manganese as principal alloying elements. In addition to automotive, construction, and transportation industries, stainless steels have a variety of applications in the food, chemical, and pharmaceutical industries. Some common products made from stainless steel are sinks, wash basins, kitchen vessels, and cutlery. Among ferritic stainless steels, type 409 can be cold-formed easily and are used for deep-drawn parts such as vessels for the chemical and food industries. In this study, forming analyses and experiments to prevent the occurrence of inferiority such as wrinkles, crack, and neck for automotive muffler part are carried out to save the optimal conditions during forming by modifying the blank size and shape, blank holding force etc.

• 대한조선학회논문집
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• 제40권6호
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• pp.20-29
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• 2003

When Arctic offshore development in the 1970's first led to the consideration of ice capable tankers, there was a high level of uncertainty over design requirements for both safety and ship performance. Also here was a lack of reliable methods to evaluate design proposals. Since that time, improved understanding of the ice environment has raised the confidence of design specifications. Parallel developments have resulted in a suite of engineering tools for ship performance evaluation at the design stage Recent development of offshore and near shore oil and gas reserves in several countries together with economic studies of increased transportation through the Russian Arctic has newly introduced the interest in ice capable tanker design. in response, Samsung Heavy Industries (SHI) applied its experience in tanker design and construction to the design of a specialized tanker with ice capability. SHI produced two prototype hull designs for further study. The performance of both hulls and of the propellers was evaluated at the Institute for Marine Dynamics (IMD) in St. John's, Newfoundland This paper discusses the development of the design, describes the model experiments to determine performance and variations, and presents the results.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.2034-2039
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• 2010

As a mass transportation system, a railway contains potential risks that may result in a high death rate and property losses. Accordingly, Railroad Safety Technology R&D Corps. is adopting the plan of the construction of Railway Safety Test Facilities as a part of the Railway Total Safety Project to enhance the railway safety, and carrying out researches on effective project management methods with Systems Engineering techniques. When a system or a service is realized, such as the Railway Total Safety Project, it needs to be verified by requirements and the process of verification is to check whether customers/stakeholders requirements have been properly transformed into a system or a service. Recently, building the standardized verification system up could be the solution to reduce possible system-failed risks. To support that, we propose the more effectual verification method of constructing the Railway Safety Test Facilities applying the systems engineering tool to the research.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1964-1969
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• 2008

A railway is a complex system integrated with a lot of technical elements such as rolling stock, power, signal control, communications, tracks, stations, operation control systems, and so on. As a mass transportation system, a railway could contain potential risks that may result in a high death rate and property losses. Accordingly, Railroad Safety Technology R&D Corps. is adopting the plan of the construction of Railway Safety Test Facilities as a part of the Railway Total Safety Project to enhance the railway safety, and carrying out researches on effective project management methods with Systems Engineering techniques. To support that, we propose the more effectual management method of constructing the Railway Safety Test Facilities applying the model-based systems engineering tool to the research.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1505-1510
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• 2008

A railway is a complex system integrated with a lot of technical elements such as trains, track facilities, human factors, operation & control and maintenance. As a mass transportation system, a railway could contain potential risks that may result in a high death rate and property losses. Accordingly, Railroad Safety Technology R&D Corps. is adopting the plan of the construction of Railway Safety Test Facilities as a part of the Railway Total Safety Project to enhance the railway safety, and carrying out researches on effective project management methods with Systems Engineering techniques. Recently, various systems engineering tools such as CORE or Cradle are applied to manage the system requirements and the project management process in the part of the aerospace engineering and automobile engineering so on. The railway industry also makes an effort to develop an efficient management skills using systems engineering tools as the railway system is multi-disciplinary. Therefore, we propose the more effectual management method of constructing the Railway Safety Test Facilities applying the systems engineering tool to the research.

• 유기물자원화
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• 제8권4호
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• pp.121-128
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• 2000

본 연구에서는 매립 폐기물 분해와 사전안정화를 위한 최적 산소 전달 방식을 평가하기 위하여 대상 매립지와 모형매립조 실험을 수행하였다. 매립년한이 오래된 매립지의 경우 낮은 유기물 함량으로 인해 저압/저유량의 연속 공기 주입방식이 효과적인 것으로 나타났다. 또한, 공기 주입 및 매립가스 추출은 유기물의 생분해 보다 매립지 내부의 공기 치환에 의한 SVE (Soil Vapor Extraction)효과가 보다 큰 것으로 나타났다. 따라서, 매립지의 공기주입 방식은 매립지의 조기안정화뿐만 아니라 매립지 굴착, 선별 및 이송시 발생될 수 있는 가스 문제를 사전에 저감할 수 있을 것으로 판단된다.

• 한국가스학회지
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• 제19권6호
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• pp.85-91
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• 2015

전 세계적으로 수소에너지에 대한 관심이 점차 증가함에 따라 수소 생산, 저장, 운송, 이용 분야에서 응용 기술의 개발이 활발히 진행되고 있다. 국내에서도 울산 수소타운을 조성하여 시범운영 중에 있어 수소에너지 응용처 확대에 대한 가능성을 높이고 있다. 울산 수소타운은 가스 사용 압력에 따라 고압부와 저압부로 구분할 수 있는데 고압부는 '고압가스안전관리법'을 적용하여 안전관리를 하고 있고 저압부는 '수소타운 시범사업의 안전관리에 관한 지침'을 적용하여 운영 중에 있다. 본 논문에서는 울산 수소타운 내 0.1MPa 이하 저압 수소 사용시설의 안전관리 효율성 향상을 위해 저압 수소사용 시설 및 안전관리 항목 분석을 통해 안전관리 방향성을 검토하고 향후 개선 방향을 제시하고자 하였다. 본 연구의 결과를 통해 국내 수소타운 활성화 및 안전 관리 효율성 증대에 도움이 될 수 있을 것으로 기대한다.

• 한국건설관리학회논문집
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• 제22권6호
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• pp.96-106
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• 2021

OSC (Off-Site Construction)기반의 PC구조는 기존의 시공 환경을 현장중심에서 공장생산-운반-현장조립의 단계로 전환하는 건설산업 혁신의 대표적 방안으로 거론된다. 그러나, 최근까지의 PC공법 관련 연구는 개별 부재의 기능개선과 생산성 증대를 위한 생산 체계 개선을 중심으로 이루어지고 있으며, 발주/설계/시공의 생애주기 단계에 보편적으로 적용할 수 있는 제도적/정책적 연구 개발은 부족한 실정이다. 특히, 표준화 된 비용산출 기준의 부재는 객관화된 적정공사비의 산출과 검증을 어렵게하여 PC공법 활성화에 장애가 되고 있다. 본 연구에서는 국내외 PC공법 공사비 기준을 조사하고 유사 표준품셈 항목을 분석하여 PC공법에 적합한 품셈 구조를 확인하였다. 이후, 현장조사를 통해 PC부재별 시공절차와 투입자원 을 확인하여 부재별 품 구성요소를 도출하였으며, 시공특성(높이, 부재중량)에 따른 품의 변화요소를 검증하여 공동주택 PC공법 현장설치에 적합한 표준품셈 체계를 제시하였다.