• 대한토목학회논문집
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• 제26권6A호
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• pp.1023-1032
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• 2006

본 논문에서는 기존 교량 유지관리방법의 한계를 극복하고 예방유지관리 체계의 구현을 위하여 새로운 교량 유지관리기법을 제안하였다. 제안된 방법은 생애주기비용뿐만 아니라 생애주기성능을 함께 고려하여 열화되는 교량의 최적 유지관리전략을 수립할 수 있다. 교량의 성능변화는 신뢰성에 기초한 안전도와 상태등급을 세분화한 상태지수에 의해 평가되며, 생애주기 비용은 직접유지관리비용뿐만 아니라 도로이용자비용과 파손비용을 고려하여 추정하였다. 교량수명 동안의 성능 및 비용과 관련된 다중목적 조합 최적화 문제인 교량 유지관리 시나리오 집합의 생성을 위해 유전자알고리즘을 적용하였다. 개발된 방법을 실교량에 적용하여 유지관리전략 수립의 과정과 효과를 고찰하였다. 이러한 결과를 통해, 개발된 방법은 유지관리를 위한 의사결정과정에 효과적으로 활용될 수 있을 것으로 판단된다.

• International Journal of Safety
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• 제10권2호
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• pp.27-31
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• 2011

As safety-related regulations for signaling systems are standardized to IEC 61508 and 62425, and others at the international level, safety activities and its verification are required. And also there is need to develop technologies for safety improvement to secure safety signaling systems in terms of technologies for safety activities on each life-cycle. In this paper it is reviewed the safety activity processes and technologies each steps of proposed processes respectively for railway signaling systems.

• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.75-80
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• 2002

Cycle life tests have been carried out to evaluate the influence of safety valve pressure on valve regulated lead/acid batteries under deep cycling applications. Batteries were cycled at 5 hour rates at 100% DOD, and safety valve pressure was set to 1.08 and 2.00 bar, respectively. The batteries lost 248.3 g and 235.3 g of water for each case after about 1,200 cycles, but the cyclic performances of the batteries were comparable. Most of the gas of the battery during discharging was hydrogen, and the oxygen concentration increased to 18% after 3 hours of charging. The micro structure of the positive active materials was completely changed and the corrosion layer of the positive grid was less than $50{\mu}m$, regardless of the pressure of the safety valve after cycle life tests. The cause of discharge capacity decrease was found to be water loss and the shedding of the positive active materials. The pressure of safety valve does not give little effect to the cyclic performances and the failure modes of the gelled electrolyte valve-regulated lead acid batteries.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1167-1173
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• 2011

This study is described for the RAMS activities of performed to 2008.12 ~ 2010.10 KTX CTC Project. RAMS activities follow EN50126, EN50128, EN50129. CENELEC standards(EN50126, EN50128, EN50129) to the System Development Life-cycle are defined. This study is RAMS activities of life-cycle that can be found to satisfy SIL2. In addition, assessment of the ISA was completed. This paper is describe RAMS activities results of each phase and Safety Case according to Verification/Validation result.

• 대한안전경영과학회지
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• 제17권3호
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• pp.239-246
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• 2015

Enforced environmental regulations call for extending the domain of manufacturers' responsibility to the entire product life cycle. To comply with the environmental regulations, manufacturers have constructed reverse logistics networks to re-collect their leftover waste for recycling consumed resources. However, the operational activities associated with storage, loading and transportation processes within the networks inevitably impose environmental burdens. Particularly, the transportation process largely influences environmental performance due to perpetual uses of transportation vehicles. Therefore, there is a need to develop an environmentally-conscious transportation model that can efficiently manage the uses of transportation vehicles. Additionally, it is vital to analyze its significances of environmental performance to compare quantitatively it with existing models. This paper proposes a transportation model for improving environmental performance in a reverse logistics network. This paper also presents a case study to perform its comparative analysis using Life Cycle Assessment that evaluates potential environmental impacts of a product system.

• 한국안전학회지
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• 제33권6호
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• pp.1-7
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• 2018

The Continuous Ship Unloader (CSU) is an equipment that unloads freight from the ship docked in the port to the land. And the design target life time is designed to be 30 to 50 years, and it is classified as a semi-permanent large facility. However, cracks may occur due to structural defects, abnormal loads, and corrosion, and fatigue failure may occur before the design life is reached. In this study, we predicted the remaining life time of the main component of the CSU considering crack. And also proposed inspection cycle for maintenance of CSU based on the results of the remaining life time prediction. For this purpose, the structure, operational stresses of the CSU were analyzed and main members were selected. And tensile tests and fatigue crack propagation tests were performed with SM490YA and SM570TMC, which are used as main materials for CSU.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.968-973
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• 2007

The systems such as the railway control system, satellite control system and nuclear power plant control system are the safety critical systems because the failure of them could lead to risk significant events. These softwares of digital systems must follow the life cycle process from the beginning of software development to guarantee their safety and reliability. The NRC(Nuclear Regulatory Commission) Reg Guide of nuclear fields, the RTCA/DO-178B standard which is used to acquire the certification for software in industrial aero field in European Union and United State, the DEF STAN 00-55 standard for the safety of electronic weapon in England, the IEC 601-1-4 for medical equipment and the IEC 62279 for railway system recommended the development life cycle. This paper introduces the development process and compares each other. Also it indicates applicable development criteria for the software of systems related to railway fields and describes the detailed procedure of development criteria. We describe the procedure to make the software development criteria in nuclear filed. For the software development related to railways, the process from plan phase to maintenance phase must be satisfied. The safety and reliability is guaranteed through these standards.

• 급식외식위생학회지
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• 제3권1호
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• pp.19-27
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• 2022

The use of cultured meat, also known as in vitro meat, is claimed to be a way of meeting the growing demand for meat worldwide in a safe and disease-free manner, without sacrificing animal and lowering greenhouse gas emissions. However, its economic feasibility is limited by its cost, scale-up complexity, public neophobia and technophobia, and an imperfect knowledge of its impacts on human health. Cultured meat, which is obtained from stem cells using tissue engineering techniques, has been described as a potential alternative to the current meat production systems, which have extensive negative effects. To ensure that a food product is safe for human consumption, it is important to consider all aspects of its life cycle. In this context, the current review analyzes the major elements of the cultured meat life cycle, including the incorrect use of chemicals, such as pesticides or antibiotics, as well as improper processing and storage methods that determine the food safety of cultured meat. The purpose of this review is to determine food safety, health issues, and the potential risks associated with cultured meat production.

• 한국건설관리학회논문집
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• 제6권4호
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• pp.164-171
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• 2005

최근 생애주기비용 분석의 중요성이 대두됨에 따라 공동주택 리모델링 사업에서의 생애주기비용 분석을 위한 이론적 모델, 표준지침 및 소프트웨어 등이 개발되어지고 있다. 그러나 현재까지도 실질적인 안전진단에 대한 과거 보수이력데이터의 부재로 인한 LCC분석 결과에 대한 신뢰수준이 여전히 미흡하다. 본 연구에서는 사례 공동주택의 신뢰성에 기초한 LCC분석을 통해 리모델링 전략을 평가하고, 장래 요구되는 리모델링 조치수준의 비교 $\cdot$ 분석을 통해 적정 경제성지수를 제시함과 동시에 최근 연구가 활발히 진행 중인 공동주택 리모델링에 대한 실적 LCC 기초자료를 얻고자 하였다. 본 연구에서 제안된 퍼지로직에 기초한 안전성평가와 LCC분석모델은 공동주택 리모델링사업에서의 가치 지향적 설계대안 선정, 경제성평가 및 합리적인 예산의 분배 등에 크게 기여할 것으로 기대된다.

• 한국건설관리학회논문집
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• 제21권4호
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• pp.50-61
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• 2020

건설산업에서 안전관리가 오랫동안 중요한 화제중의 하나로 대두되고 있으며 수많은 노력에도 불구하고 여전히 타 산업에 비해 높은 재해율을 보이고 있다. 이와 관련되어 많은 연구들이 진행되었으며, 대부분 시공자 또는 시공단계를 중심으로 진행되었다. 그러나 사업초기단계가 건설안전에 미치는 영향이 가장 높고 발주자 등 사업초기단계의 의사결정자들이 중요한 작용을 함에도 불구하고, 아직까지 건설사업 생애주기를 포괄하는 안전관리체계가 미흡한 실정이다. 게다가 건설사업에서 방대한 정보가 생성되지만, 이러한 정보들은 각 생애주기를 거듭할수록 정보들의 가치가 증가하는 반면에 비효율적인 측면을 보이고 있다. 이는 참여자들 간의 부족한 정보 공유 및 전달과 미흡한 표준으로 인한 것으로 판단되며, 이는 또한 정보가치들의 손실을 야기한다. 따라서 본 연구에서는 건설산업 측면에서 안전관리 정보이양의 효율성을 분석하는 것을 목적으로 하며, 이를 위해 우선적으로 건설안전 정보를 체계적이고 효율적으로 관리 및 활용하기 위한 안전관리 Framework을 '안전관리 업무기능', '건설사업 생애주기', '산업위계'를 포괄하여 제안하고, '안전관리 업무기능'을 계층적 구조로 5개의 대분류, 13개의 중분류, 32개의 소분류로 세분화함으로써 Framework을 구체화하였다. 다음으로, 안전정보이양의 효율성을 분석하기 위해 '업무기능의 중요도'와 '정보이양의 효율성'을 평가지표로 설정하고 전문가 인터뷰를 통해 평가를 실시하였다. 본 연구결과는 건설산업에서 안전관리를 보다 체계적이고 효율적으로 구현하는 기반을 마련하고 나아가 안전관리 역량을 강화하기 위한 기초자료로의 활용을 기대한다.