• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.324-327
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• 2001

This paper shows an example of the Design Review and Common-Cause Failure (CCF) Modeling of mechanical Parts. Reliability should be continuously monitored during the entire period of design. Design Review is the procedure to improve the reliability for the product. We proposed the reliability assessment and design review method. CCF Model is the general dependent model considering the failure mode effects several component simultaneously. This study considers the computation of the network with dependent components. It is important that CCF model is applied for mechanical pars.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2010년도 춘계학술대회
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• pp.254-261
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• 2010

The increase in hazard level is attributed to the industrial hazard environment; complete national environmental hazards to human health include climate change. The damage level in Korea from 1993 to 2009 has exceeded the Increase In adverse environmental conditions. Priority areas of concern will include those risks that are most likely to occur and are expensive when they do take place such as accident or injury at a community pool. Therefore, in this paper, we suggest the System Engineering method for application to the railway RAMS. Recently, the requirement of high-integrity level of infrastructure has been deemed important. The systems level approach is defined through the assessment of the RAMS interactions between elements of complex system applications.

• 한국신뢰성학회:학술대회논문집
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• 한국신뢰성학회 2002년도 정기학술대회
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• pp.387-401
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• 2002

The Digital Engineered Safety Feature Actuation System (DESFAS) of nuclear power plants actuates safety systems to mitigate severe accidents occurred in nuclear power plants. The reliability of the system should be evaluated in order to meet the reliability criteria of nuclear power plants. In this work, we have calculated and evaluated the lifetime of DESFAS by using Reliability Block Diagram (RBD) and failure rates of digital control components. Surveillance test is assumed in the evaluation. The result shows that the digital control component can be used in DESFAS system.

• 한국암반공학회:학술대회논문집
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• 한국암반공학회 2000년도 암반공학문제의 수치해석(Numerical Analysis in Rock Engineering Problems)
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• pp.223-228
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• 2000

본 연구에서는 발파 설계를 쉽게 하기 위하여 RBD(Rock Blasting Design)프로그램을 개발하였다 이 프로그램은 시험 발파 설계, 벤치 발파 설계, 그리고 발파 진동 해석의 기능을 가지며, 지질 특성 값과 발파 상수를 데이터베이스로 제공하고, 여러 상수 값을 재 입력함으로써 보다 빠르고 간편하게 설계할 수 있고 한번 입력한 상수 값을 사용자가 재사용 할 수 있도록 하였다.

• Earthquakes and Structures
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• 제11권6호
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• pp.967-982
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• 2016

Current codes design the buildings based on life safety criteria. In a performance-based design (PBD) approach, decisions are made based on demands, such as target displacement and performance of structure in use. This type of design prevents loss of life but does not limit damages or maintain functionality. As a newly developed method, resilience-based design (RBD) aims to maintain functionality of buildings and provide liveable conditions after strong ground movement. In this paper, the seismic performance of plain and strengthened RC frames (an eight-story and two low-rise) is evaluated. In order to evaluate earthquake performance of the frames, the performance points of the frames are calculated by the capacity spectrum method (CSM) of ATC-40. This method estimates earthquake-induced deformation of an inelastic system using a reduced response spectrum. Finally, the seismic performances of the frames are evaluated and the results are compared with a resilience-based design criterion.

• 수산해양기술연구
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• 제33권4호
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• pp.334-345
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• 1997

Reliability-based design approaches are needed for cylindrical shell structure whose design and operational experiences are few and which are subjected to external loads of random loads. In designing new type of structure, it is very difficult to evaluate the safety factors due to lack of previous design data and operational experience. To solve the above mentioned problem, much attention is being focussed on rational reliability based design approaches. This paper deals with weight-optional reliability-based design of cylindrical shell structure subjected to structural reliability constraints taking into account of the effect of local buckling and interactive behavior between local and global buckling. Present mentioned is compared with the exiting optional design method based only on safety factors. Numerical simulation reveals that the present method leads to lighter structure (4% reduction in weight compared to the existing optimal design) with the same reliability index. For larger structures with more number of structural members and possible failure modes, the present W0RBD procedure will be an efficient tool in designing cost-effective rationalized economic design.

• 산업경영시스템학회지
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• 제30권1호
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• pp.1-7
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• 2007

This paper addresses a the maintenance system based on the concept of RAMS (Reliability, Availability, Maintenance, Safety) for the effective maintenance of the urban transit. A systematic approach for developing a cost-effective maintenance strategy based on the component reliability of the system in question is performed according to the following steps : definition of function, functional failures of the systems, construction of RBD (Reliability Block Diagram), and the calculation of reliability indices. The developed preventive maintenance system generates maintenance plan and repair request based on the analysed RAMS data of components and maintenance experience.

• 대한기계학회논문집A
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• 제28권5호
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• pp.593-602
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• 2004

We have developed a digital control rod control system not only to improve its performance but also to improve its reliability and speed of response so that it can replace the old fashioned analog system. However, a new developed digital control system should be tested to prove the validity by using any prototype or mock-up before application. The reliability prediction and the reliability block diagram analysis methods were adopted to verify the reliability of the developed hardware. For the case of software, especially fur a new developed control algorithm it has been tested to prove performances and validation by using a dynamic simulator and mock-up of control rod drive mechanism altogether. Here we want to present some key factors regarding to the new developed digital system with some verification procedures.

• Journal of the Korean Wood Science and Technology
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• 제31권5호
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• pp.72-79
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• 2003

신뢰성 설계에서 재료강도의 분포 특성은 기본적인 입력 변수로 사용된다. 따라서 강도특성의 분포형태 및 그에 따른 인자들을 정확하게 결정하는 것은 신뢰성 설계를 위한 필수적인 작업이다. 지금까지 강도성능 평가는 주로 무결점 소시편에 대한 실험결과가 사용되어 왔다. 그러나 이러한 방법은 부재가 실재 사용되는 조건을 제대로 반영하지 못함에 따른 오차를 포함하게 된다. 본 연구에서는 구조재로 많이 사용되는 2×6부재(38 mm×140 mm, 길이 3.0 m) 498본에 대하여 육안검사를 통해 등급을 구분하고, 휨시험을 실시하였다. 신뢰성 설계로 전환을 위해 각 등급의 강도특성에 대한 분포형태 및 인자를 결정하였다. 분포형태의 결정을 위해 정규분포, 대수정규분포, 웨이블분포의 세가지 분포형태에 대한 square error를 비교하고, KS test를 통하여 결정된 분포형태의 적합성을 확인하였다. 모든 등급에서 휨강도(MOR)의 가장 적합한 분포형태는 웨이블분포로 나타났으며, 휨탄성계수의 경우는 정규분포가 가장 적합한 것으로 나타났다.

• IMMUNE NETWORK
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• 제20권5호
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• pp.41.1-41.11
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• 2020

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) is a positive-sense single-stranded RNA (+ssRNA) that causes coronavirus disease 2019 (COVID-19). The viral genome encodes twelve genes for viral replication and infection. The third open reading frame is the spike (S) gene that encodes for the spike glycoprotein interacting with specific cell surface receptor - angiotensin converting enzyme 2 (ACE2) - on the host cell membrane. Most recent studies identified a single point mutation in S gene. A single point mutation in S gene leading to an amino acid substitution at codon 614 from an aspartic acid 614 into glycine (D614G) resulted in greater infectivity compared to the wild type SARS-CoV2. We were interested in investigating the mutation region of S gene of SARS-CoV2 from Korean COVID-19 patients. New mutation sites were found in the critical receptor binding domain (RBD) of S gene, which is adjacent to the aforementioned D614G mutation residue. This specific sequence data demonstrated the active progression of SARS-CoV2 by mutations in the RBD of S gene. The sequence information of new mutations is critical to the development of recombinant SARS-CoV2 spike antigens, which may be required to improve and advance the strategy against a wide range of possible SARS-CoV2 mutations.