• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 심포지엄 논문집 정보 및 제어부문
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• pp.275-277
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• 2005

In a lithium-ion battery which is being used in many portable electronic goods, electrolyte is disaggregated and then the gas is happened when electric charging volt is over the 4.5V. So, the pressure on the safety valve is increased and electrolyte is leaked out in the cell. It leads to the risk of explosion. On the other hand, in the case which the battery is discharged excessively, the negative pole is damaged and the performance of the battery is deteriorated. The protection module of a lithium-ion battery is used for preventing such risk and the inspection system is needed to check the performance of such protection module. In this research, a PC-based auto inspection system is developed for the inspection of a battery protection module using Dallas chipset. In the inspection system, AVRl28 chip is used as a controller and the communication protocol is developed for the data communication between the protection module and the AVR128 chip. And GPIB interface is used for the control of measuring devices. Also, MMI environment is developed using LabView for convenient monitoring by the tester.

• 한국가스학회지
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• 제23권3호
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• pp.33-39
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• 2019

2010년대에 들어서 노후화된 공정으로 인하여 많은 공장들의 안전이 보장되지 않은 채로 가동되고 있다. 공정 및 설비의 노후화 문제를 근본적으로 해결하기는 어렵지만, 사전에 위험성 평가로 위험을 예방할 수있다. 본 연구는 CDU(Crude Distillation Unit)의 탈황 장비에 있는 배관에서 황으로 인한 부식을 타겟으로 지정하였고, API RP 581를 참고한 RBI(Risk Based Inspection)기법으로 위험성 평가를 실시하였다. RBI 기법은 Frequency와 Consequence의 조합으로 Risk를 표현하고, 이들을 바탕으로 Risk Matrix를 만든다. 본 연구는 배관의 Hole Size를 Small과 Medium으로, Frequency의 감도는 'Low'로 선택하여 진행하였다. 기준을 통해 만들어진 Risk Matrix를 참고하여 배관에서 황으로 인한 부식의 사고 위험성을 평가하고 향후 사고 방지 계획을 세울 수 있다. 또한 이와 비슷한 방법으로 노후화에 대한 예방을 한다면 보이지 않는 크고 작은 사고들도 예방 할 수 있다.

• 설비공학논문집
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• 제25권2호
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• pp.70-78
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• 2013

Plants which are having conditions of high temperature and pressure always are exposed to danger. In order to prevent unexpected accidents, safety management that can effectively and appropriately examine facilities is required in plant operation. RBI(Risk-Based Inspection) technology in API 581 is one of standard management technique for evaluating risk on petroleum plants. There are qualitative and quantitative assessments in RBI methodology. Quantitative evaluation step is complex and required much information, so high-risk facilities in plant are selected firstly by qualitative method. Qualitative RBI is performed by choosing the answer in prepared questionnaire. However, it is difficult to believe thoroughly results from survey including ambiguous information. In this study, the procedure of qualitative RBI analysis with considering probability distribution concept were proposed by using Monte Carlo simulation method in order to increase reliability in spite of uncertain factors. In addition, qualitative risk of cooling system for LNG plant was evaluated using proposed procedure. Although 20 items of total 39 assessment items are applied to uncertain factors, risk section of high probability(89%) were verified. The detailed results were described in manuscript.

• 대한기계학회논문집A
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• 제29권10호
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• pp.1392-1398
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• 2005

API 581 guideline provides a methodology for calculating the risks of equipments in refinery or petrochemical plant. However, especially in part of the consequence of failure, there is a major limitation of its application to the petrochemical plant directly since only a representative material is considered in calculating the risk while the equipment is composed of numerous materials. The objectives of this paper are to propose an enhanced risk-based inspection (RBI) technique to resolve shortcomings inclusive of the above issue and to assess the risks of typical petrochemical equipments. In this respect, a program incorporating material database was developed to fully incorporate the characteristics of different materials. The proposed RBI program consists of qualitative, semi-quantitative and quantitative risk evaluation modules in which toxic materials as well as representative materials were selected automatically for comparison to those in the current guideline. It has been applied to assess the risks of equipments in ethylene facilities of petrochemical plants. Thereby, more realistic evaluation results were obtained and applicability of the proposed RBI program was proven.

• 대한조선학회논문집
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• 제57권1호
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• pp.1-7
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• 2020

In general, an inspection schedule is established based on the long-term fatigue life during the design stage. However, in the design stage, it is difficult to clearly identify the uncertainty factors affecting long-term fatigue life. In this study, the probabilistic fatigue life assessment was conducted in accordance with the methodology of DNV-GL. Firstly, The initial crack distribution estimated through the initial crack propagation analysis was updated by reflecting the results of crack inspection. Secondly, the updated crack distribution was compared with the initial crack distribution, and the probability of failure was updated with the effect of crack inspection.

• 대한기계학회논문집A
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• 제30권1호
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• pp.90-96
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• 2006

Since Risk Based Inspection(RBI) was introduced to quality the risks for jet engine and nuclear power, the technique has been expanded to the area of petrochemical plant. Recently among USA and Europe, window-based computer programme for RBI has been rapidly developed. When local companies procure such program to apply to their plants, it is difficult to build up a proper database as well as expect a good result. In this regards, K-RBI programme accustomed to Korean environments was developed. After completion of the programme in 2004, it was tested by 2 local petrochemical plants and was produced fruitful results. By using these programme, we are expecting accident prevention through risk based planning and implementing of equipment inspection, and saving dollars caused by procuring foreign expensive programme.

• 한국가스학회:학술대회논문집
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• 한국가스학회 2006년도 추계학술발표회 논문집
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• pp.90-94
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• 2006

• Journal of Mechanical Science and Technology
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• 제20권4호
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• pp.437-446
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• 2006

Laser vision inspection systems are becoming popular for automated inspection of manufactured components. The performance of such systems can be enhanced by improving accuracy of the hardware and robustness of the software used in the system. This paper presents a new approach for enhancing the capability of a laser vision system by applying hardware compensation and using efficient analysis software. A 3D geometrical model is developed to study and compensate for possible distortions in installation of gantry robot on which the vision system is mounted. Appropriate compensation is applied to the inspection data obtained from the laser vision system based on the parameters in 3D model. The present laser vision system is used for dimensional inspection of car chassis sub frame and lower arm assembly module. An algorithm based on simplex search techniques is used for analyzing the compensated inspection data. The details of 3D model, parameters used for compensation and the measurement data obtained from the system are presented in this paper. The details of search algorithm used for analyzing the measurement data and the results obtained are also presented in the paper. It is observed from the results that, by applying compensation and using appropriate algorithms for analyzing, the error in evaluation of the inspection data can be significantly minimized, thus reducing the risk of rejecting good parts.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2007년도 춘계학술대회
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• pp.143-149
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• 2007

현행 우리나라의 검사제도는 사업장의 자율관리 능력을 고려하지 않고, 설비의 노후화 및 위험도와 무관하게 획일화된 방식으로 적용하여 설비의 안전성을 확보하지 못할 뿐만 아니라 정기 및 자체 검사를 병행하여 많은 불편이 있다. 따라서 사업장의 불편을 해소하고, 설비의 안전성과 신뢰도를 높일 수 있는 위험기반검사(risk based inspection, RBI)를 국내 실정에 적합하게 도입하기 위하여 사업장, 정부 및 관련 기관에서 향후 추진해야할 방향에 대하여 분석하였다. 국내에서 위험기반검사 제도가 정착될 수 있기 위해서는 먼저 법적 근거가 마련되어야 하며, 법적 제도가 마련되면 사업장에서 RBI를 적용 시 이를 검증하고, 관리할 수 있는 인증기구의 설치가 필요하다. 또한 위험기반검사를 수행하는 사업장에 대해서는 공정안전이행수준과 같은 위험기반검사 이행수준평가를 도입하고, 차등 적용하여 사업장을 관리하는 것이 바람직하다.

• Structural Engineering and Mechanics
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• 제64권3호
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• pp.347-352
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• 2017

The poor maintenance practice increases the possibility of system failure. Subsequently, the consequences of failure fall on the aspects of output, safety and healthy, environmental integrity, system quality, and customer satisfaction. Conditionbased maintenance is seen as a potential strategy to improve performance. Whereby, the key success factor of this maintenance strategy is identified as the system inspection. This study aims to investigate the association between system breakdown rate and frequency of inspection. A mixed method approach is implemented by distributing questionnaire and interviewing for data collection. Subsequently, descriptive analysis, correlation analysis and regression are adopted to analyse the collected data from 100 respondents and the results are validated with interview data of 10 interviewees. The research result establishes significant relationship between the system breakdown rate and the frequency of inspection. Additionally, the result of regression analysis confirms that the frequency of inspection is the significant predictor of system breakdown rate. Planning of accurate inspection frequency is crucial to secure the system performance. Hence, the research signifies the importance to carry out regular inspection towards the building systems and components. As a recommendation, the maintenance personnel should assess the risk criticality of the building systems. Then, continuously monitor the condition of critical building systems; regularly inspect the condition of non-critical building systems and randomly inspect all of them.