• 한국안전학회지
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• 제30권1호
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• pp.87-93
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• 2015

Most incidents and accidents involved human during operating NPPs have a tendency to be structured by complicated and various organizational, individual, and environmental factors. The salient feature of the human error in NPP was extremely low frequency, extremely high complicated and extremely serious damage of human life and property. Our research team defined as 'rare human errors'. To prevent the rare human errors, the most researchers and analysts insist invariably that the root causes be made clear. The making them clear, however, is difficult because their root causes are very various and uncertain. However, These tools have limits that they do not adapt all operating situations and circumstances such as design base events. The purpose of this study is to improve the rare human error hazards consider the situational contex. Through this challenging try based on evidences to the human errors could be useful to prevent rare and critical events can occur in the future.

• 제어로봇시스템학회논문지
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• 제9권10호
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• pp.774-781
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• 2003

The important factors that cause position error in X-Y robot are inertial force, frictions and spring distortion in screw or coupling. We have to estimate these factors precisely to correct position errors, Which is very difficult. In this paper, we makes systems to inspect metal stencil which is used to print solder paste on pads of SMD of PCB with low precision X-Y robot and vision system. To correct position error that is caused by low precision X-Y robot, we defines position error vector that is formed with position of objects that exist in reference and camera image. We apply MHT(Modified Hough Transformation) for the aim of determining the dominant position error vector. We modify reference image using extracted dominant position error vector and obtain reference image that is the same with camera image. Effectiveness and performance of this method are verified by simulation and experiment.

• 한국항공운항학회지
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• 제25권3호
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• pp.81-88
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• 2017

Aircraft maintenance failure doesn't only threaten flight safety but also causes significant economic losses such as flight delays, flight cancellations, air turn backs and diversion and so on. Therefore, the efforts should be made to detect the contributing factors that cause such maintenance failure and eliminate them. In this study, by analyzing factors contributing to system failure using the Maintenance Error Decision Aid (MEDA) model based on stochastic relations between the contribution factors, system failure and events, we will draw a improvement plan to aircraft maintenance defects.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 추계학술대회 논문집
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• pp.47-52
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• 2002

There are many factors in machine tool error. These are thermal deformation, geometric error, machine's part assembly error, error caused by tool bending. Among them thermal error is 70% of total error of machine tool . Prediction of thermal error is very difficult. because of nonlinear tendency of machine tool deformation. In this study, we tried thermal error prediction by using multi regression analysis.

• 터널과지하공간
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• 제24권5호
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• pp.386-394
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• 2014

발파를 이용한 채광작업에 있어서 천공의 정확성은 발파의 효율성을 결정할 수 있는 중요한 요소 중의 하나이며, 따라서 천공오차의 발생 원인에 대한 분석과 천공오차의 발생 정도를 줄일 수 있는 대책 마련은 발파의 효율성 및 안전성 확보에서 매우 중요하다. 본 연구에서는 천공오차의 발생 원인을 제어가능 요인과 제어불가능 요인으로 나누어 분석하였으며 현장조사와 AHP 분석을 통하여 천공오차를 유발하는 요인들의 영향성을 살펴보았다. 또한 이들 간의 가중치 분석을 통해 천공오차를 낮출 수 있는 효과적인 대책을 제시하였다.

• 한국항해항만학회지
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• 제34권2호
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• pp.145-152
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• 2010

The management of safety at sea is based on a set of internationally accepted regulations and codes, governing or guiding the design and operation of ships. The regulations most directly concerned with human safety and protection of the environment are, in general, agreed internationally through the International Maritime Organization(IMO). IMO has continuously dealt with safety problems and, recognized that the human element is a key factor in both safety and pollution prevention issues(IMO, 2010). This paper proposes a human error analysis methodology which is based on the human error taxonomy and theories (SHELL model, GEMS model and etc.) that were discussed in the IMO guidelines for the investigation of human factors in marine casualties and incidents. In this paper, a cognitive process model, a human error analysis technique and a marine accident causal chains focused on human factors are discussed, and towing vessel collision accidents are analyzed as a case study in order to examine the applicability of the human error analysis technique to marine accidents. Also human errors related to those towing vessel collision accidents and their underlying factors are discussed in detail.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1996년도 춘계학술대회논문집
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• pp.113-127
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• 1996

In Human Reliability Analysis(HRA), the uncertainties involved in many factors that affect human reliability have to be represented as the quantitative forms. Conventional probability- based human reliability theory is used to evaluate the effect of those uncertainties but it is pointed out that the actual human reliability should be different from that of conventional one. Conventional HRA makes use of error rates, however, it is difficult to collect data enough to estimate these error rates, and the estimates of error rates are dependent only on engineering judgement. In this paper, the error possibility that is proposed by Onisawa is used to represent human reliability, and the error possibility is obtained by use of fuzzy reasoning that plays an important role to clarify the relation between human reliability and human error. Also, assuming these factors are connected to the top event through Fault Tree structure, the influence and correlation of these factors are measured by fuzzy operation. When a fuzzy operation is applied to Fault Tree Analysis, it is possible to simplify the operation applying the logic disjuction and logic conjuction to structure function, and the structure of human reliability can be represented as membership function of the top event. Also, on the basis of the the membership function, the characteristics of human reliability can be evaluated by use of the concept of pattern recognition.

• 한국공작기계학회논문집
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• 제12권4호
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• pp.36-42
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• 2003

Theodolite measurement system is non-contacted 3-dimensional measurement system. The system accuracy is ${\pm}0.5mm$or better for distance 0~100m. And the system is used for the measurement of a product of middle and large scale. This study is performed for the measurement error factors of the system. We could know that the main measurement error factors are temperature, illumination and skill. Also, we performed the study for the effect according to the height difference of scale bar.

• 한국안전학회지
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• 제12권1호
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• pp.113-121
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• 1997

Human reliability attempts to make precise quantitative analyses and predictions of the performance of human-machine(or product) systems. In order to yield more precise human error analysis, precise human error probabilities(HEPs) must be used in the analysis. However, because human behavior is influenced by factors that are called performance shaping factors(PSFs), the effects of PSFs must be considered to obtain precise HEPs, These are called basic HEPs or situation-specific HEPs. This paper presents a theoretical method for obtaining basic HEPs (i.e. , considering PSFs) in quantitative human error analysis. In this method, the weight which characterizes the degree of importance of several PSFs is obtained by the analytic hierarchy process. The quality scores of PSFs in the task situation are obtained by percentile concept. These scores are used in conjunction with the relative Importance weights of PSFs to compute the composite quality percentile score of PSFs in the task situation. Then, a new mapping method of the composite quality percentile score of PSFs into a situation-specific basic HEP is proposed with a numerical example.

• 대한인간공학회지
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• 제11권2호
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• pp.35-45
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• 1992

This study is to define a congitive paradigm including a new model of common cause human behavior error domain and to analyze their causal factors and their properties of common cause human error characteristics in software engineering. A laboratory study was performed to analyze the common causes of human behavior domain error in software development and to identify software design factors contributing to the common cause effects in common cause failure redundancy. The results and analytical paradigm developed in this research can be applied to reliabbility improvement and cost reduction in software development for many applications. Results are also expected to provide training guidelines for software engineers and for more effective design of ultra-high reliable software packages.