• Journal of the Ergonomics Society of Korea
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• v.30 no.5
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• pp.645-650
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• 2011

Objective: The aim of this study is to design a sampling inspection plan with human error which is changing according to inspection time. Background: Typical sampling inspection plans have been established typically based on an assumption of the perfect inspection without human error. However, most of all inspection tasks include human errors in the process of inspection. Therefore, a sampling inspection plan should be designed with consideration of imperfect inspection. Method: A model for single sampling inspection plans were proposed for the cases that visual inspection error rate is changing according to inspection time. Additionally, a sampling inspection plan for an optimal inspection time was proposed. In order to show an applied example of the proposed model, an experiment for visual inspection task was performed and the inspection error rates were measured according to the inspection time. Results: Inspection error rates changed according to inspection time. The inspection error rate could be reflected on the single sampling inspection plans for attribute. In particular, inspection error rate in an optimal inspection time may be used for a reasonable single sampling plan in a practical view. Conclusion: Human error rate in inspection tasks should be reflected on typical single sampling inspection plans. A sampling inspection plan with consideration of human error requires more sampling number than a typical sampling plan with perfect inspection. Application: The result of this research may help to determine more practical sampling inspection plan rather than typical one.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.145-146
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• 2008

The appearance inspection of various electronic products and parts has been executed by the eyesight of human. But inspection by eyesight cannot bring about uniform inspection result. Because the appearance inspection result by eyesight of human is changed by condition of physical and spirit of the checker. So machine vision inspection system is currently used to many appearance inspection fields instead of the checker. However the inspection result of machine vision is changed by the illumination of workplace. Therefore we proposed histogram specification in this paper for machine vision inspection accuracy. As a result of histogram specification algorithm, we could increase the exactness of visual inspection and prevent system error from physical and spirit condition of human. More specifically, average inspection error rate was 7.5[%] in existing inspection method but we could see 0.6[%] error rate after applying the algorithm which is presented in this paper.

• Nuclear Engineering and Technology
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• v.26 no.1
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• pp.9-18
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• 1994

The engineered safeguards of Wolsung nuclear power plant unit 1 contain redundant systems of 2-out-of-3 logic which are not operating under normal conditions but are called upon to act when emergency conditions develop. To ensure their operability, the systems are periodically tested. In this work, we develop the unavailability formulae for 2-out-of-3 logic configurations which take into account the failure probability of the channels tested due to human error in the simultaneous testing scheme. We also develop the model for the probability that the reactor is tripped during the surveillance test due to either system failure or human error. We determined the optimal inspection periods of safety systems, taking into account both the unavailability of the safety system and the probability that the reactor is tripped during the surveillance test. We compared the results with the inspection periods currently used at Wolsung NPP Unit 1. As a result, the inspection periods obtained using a minimum human error (8.24 $\times$ 1$^{-6}$ ) are shorter than those currently used in Wolsung NPP unit 1 whereas the inspection periods obtained using a maximum human error are (4.44 $\times$ 10$^{-4}$ ) longer than those used in Wolsung NPP unit 1.

• Journal of the Korean Professional Engineers Association
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• v.34 no.3
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• pp.22-27
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• 2001

About 70% -80% of the serious injury that occure in the chemical product small manufacturing industries is caused by human error. but technical development for analysis and inspection to preestimate and exclude such human error is still insufficient. Small - to - medium sited enterprises are economically vulnerable and technical foundations for safety management is week Under such circumstances development of easy to use computerized support programs that can be operated without the help of professioanals are keenly needed.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.431-433
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• 2006

The goal of this paper is improvement of vision inspection accuracy by using histogram specification operation. The histogram is composed of horizontal axis of image intensity value and vertical axis of pixel number in image. In appearance vision inspection, the histogram of reference image and input image are different because of minutely lighting distinction. The minutely lighting distinction is main reason of vision inspection error in many cases. Therefore we made an effort for elevation of vision inspection accuracy by making the identical histogram of reference image and input image. As a result of this area separation histogram specification algorithm, we could increase the exactness of vision inspection and prevent system error from physical and spirit condition of human. Also this system has been developed only using PC, CCD Camera and Visual C++ for universal workplace.

• Journal of the Ergonomics Society of Korea
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• v.30 no.1
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• pp.19-28
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• 2011

Objective: The aim of this study is to reclassify human errors and to develop hands-on tools to apply the new classification for preventing human error accidents in highway construction site. Background: The main cause of accidents in highway construction was reported as the carelessness of workers. However, such diagnosis could not help us operationally prevent accidents in real workplace. Method: The accidents in highway construction were reanalyzed and the causes of human error were reclassified in order to educate and improve the awareness of human error in highway construction. Field survey and interview with safety managers and workers were conducted to find the causal relationship between the actual accidents and the human errors. Results: The most frequently observed human errors in highway construction were classified into six categories such as mis-perception, distraction, memory fail, slip, cognition error and mis-judgment. In order to provide hands-on tools to increase the awareness of human error in construction field, the human error checklist and card sorting diary were developed. Especially, the card sorting diary was designed to increase the ability in human error inspection of safety manager at construction site. Moreover, posters were developed based on actual accident cases. Conclusion: We suggested that the improved awareness and analytical report on checklist, card sorting diary and posters for construction field could collectively prevent the accident. Application: The classification of human error, hands-on tools and posters can be directly applicable on highway construction site. This analytical and collective approach preventing human error-related accident could be extended to other construction workplaces.

• Journal of the Korean Institute of Navigation
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• v.24 no.1
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• pp.23-34
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• 2000

The human error or error involved with human is still the major portion of the causes of marine casualties and attracting a great concern in ship operation. However, there are not so many researches conducted to investigate or develop methodologies for analyzing such causes of human error in maritime industry, which may be caused by the variety of factors affecting the performance of ship operation and the characteristics of human being. This paper aims to study the methodologies used in investigating human factors or errors in maritime field through the investigation of researches performed so far. The methodology for human factors can be usually classified into one of three types; descriptive studies, experimental research and evaluation research. Also there are many different kinds of applied researches for some specific subjects. Prior to the investigation of the root cause of marine accident related with human error, clear concept of the human factors and systematic taxonomy shall be established. Moreover, it is very important considerations in case of casualty inspection on human factors that the inspector on the accident shall have adequate knowledges, understandings on the concept of human factors including the way of research more than those of methodologies and techniques.

• Journal of Advanced Navigation Technology
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• v.23 no.1
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• pp.8-19
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• 2019

Pilots have used checklist as a valuable tool to improve aviation safety and to reduce human error. A checklist however is too complex for a student pilot to use with less flight experience or time than a commercial pilot. It is agreed upon such complex checklist be a factor to threaten aviation safety for student pilots. This paper has focused on a checklist by dividing it into a couple of basic three flight procedures. Making exploratory case study of student pilots, researchers could analyze the correlation between checklist factors and those of human errors. First of all, it was necessary for student pilots to be educated professional knowledge regarding aircraft structures and engines to perform preflight inspection reducing human errors. Moreover it was recommended student pilots as well as maintenance crew confirm checklist together to enhance aviation safety.

• Korean Journal of Construction Engineering and Management
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• v.25 no.2
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• pp.69-80
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• 2024

Currently rebar spacing inspection is carried out by human inspectors who heavily rely on their individual experience, lacking a guarantee of objectivity and accuracy in the inspection process. In addition, if incorrectly placed rebars are identified, the inspector need to correct them. Recently, laser scanning and AR technologies have been widely used because of their merits of measurement accuracy and visualization. This study proposes a technology for rebar spacing inspection and fixing by combining laser scanning and AR technology. First, scan data acquisition of rebar layers is performed and the raw scan data is processed. Second, AR-based visualization and fixing are performed by comparing the design model with the model generated from the scan data. To verify the developed technique, performance comparison test is conducted by comparing with existing drawing-based method in terms of inspection time, error detection rate, cognitive load, and situational awareness ability. It is found from the result of the experiment that the AR-based rebar inspection and fixing technology is faster than the drawing-based method, but there was no significant difference between the two groups in error identification rate, cognitive load, and situational awareness ability. Based on the experimental results, the proposed AR-based rebar spacing inspection and fixing technology is expected to be highly useful throughout the construction industry.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.6
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• pp.80-85
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• 2010

BGA 409 chip currently the most as a visual inspection of the exterior inspection is conducted. Human depending on visual inspection of the exterior inspection of the current state of testers, depending on how the test results because the change is difficult to expect reliable results. Therefore, the challenges of visual inspection of BGA solder balls to improve the visual inspection technique was developed. However, BGA solder ball size of the microstructure and the characteristics of the distinction between hard test the accuracy of the fall orientation error has a problem. In this paper BGA solder balls exterior inspection of the accuracy to improve the edge detection algorithm, the complement of features and only the comparison proposed a pattern-matching techniques, based on the characteristics of spatial configuration of the area by improving the standard error of the orientation proposed improvements.