• Title/Summary/Keyword: Difference of Inspection

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An Effect of Similarity Judgement on Human Performance in Inspection Tasks (유사성(類似性) 판단(判斷)과 검사수행도(檢査遂行度)에 관한 연구)

  • Son, Il-Mun;Lee, Dong-Chun;Lee, Sang-Do
    • Journal of Korean Society for Quality Management
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    • v.20 no.2
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    • pp.109-117
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    • 1992
  • An inspection task largely can be seen as a job divided up into a series of visual search and classification subtasks. In these subtasks, an Inspector must performs to compare the standard references proposed in visual environments and recalled in his memory with the visual stimuli to be inspected. It means that the judgement of similarity should be demanded on inspection tasks. Therefore, the inspector's ability for the judgement of similarity and the difference similarity between inspection materials are important factors to effect on performances in inspection tasks. In this paper, to analysis the effect of these factors on inspection time, an inspection task is designed and suggested by means of computer simulator. Especially, the skin conductance responses(SCR) of subjects are measured to evaluate the complexity of tasks due to the difference of similarity between materials. In the results of experiment, the more similar or different the difference of similarity between materials is, the shorter the inspection time is because of the reduction of task complexity. And, When the inspector's cognition for similarity between materials is consistanct, the inpsection time is improved. Concludingly, the consistency of reponses for similarity judgement becomes a measurement to present the performance levels. And the information of inspection time that due to the difference of similarity between materials must be considered in planning and scheduling inspection tasks.

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Evaluation on the Effect of Ultrasonic Testing due to Internal Medium of Pipe in Nuclear Power Plant (원자력발전소 배관 내부 매질이 초음파검사에 미치는 영향 평가)

  • Yoon, Byung Sik;Kim, Yong Sik;Yang, Seung Han
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.9 no.1
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    • pp.25-30
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    • 2013
  • The periodic inspection of piping and pressure vessels welds in nuclear power plant has to provide reliable result related to weld flaws, such as location, maximum amplitude response, ultrasonic length, height and finally the nature or flaw pattern. The founded flaw in ultrasonic inspection is accepted or rejected based on these data. Specially, the amplitude of flaw response is used as basic parameter for flaw sizing and it may cause some deviation in length sizing result. Currently the ultrasonic inspections in nuclear power plant components are performed by specific inspection procedure which describing inspection technique include inspection system, calibration methodology and flaw characterizing. To perform ultrasonic inspection during in-service inspection, reference gain should be established before starting ultrasonic inspection by the requirement of ASME code. This reference gain used as basic criteria to evaluate flaw sizing. Sometimes, a little difference in establishing reference gain between calibration and field condition can lead to deviation in flaw sizing. Due to this difference, the inspection result may cause flaw sizing error. Therefore, the objective of this study is to compare and evaluate the ultrasonic amplitude difference between air filled and water filled pipe in nuclear power plant. Additionally, the accuracy of flaw sizing is estimated by comparing both conditions.

Car Engine Sealing Inspection System Based on Analysis of Difference Image (차영상 분석 기반의 자동차 엔진 실링상태 검사 시스템)

  • Choi, Sang-Bok;Ban, Sang-Woo;Kim, Ki-Taeg
    • Journal of Korea Multimedia Society
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    • v.14 no.3
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    • pp.356-367
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    • 2011
  • In this paper, we proposed a new car engine sealing inspection system based on image processing and understanding. The car engine sealing inspection plays very important role for protecting leakage caused by inappropriate sealing, which is a crucial point for productivity of car engines. The proposed inspection system has been aimed to enhance the previously proposed sealing inspection systems based on image processing, which have high computation complexity and low performance for correctly inspecting some contamination by oil with similar color with that of sealing. Moreover, the previously proposed system has a difficulty in installing the camera system on the sealing machine. The proposed system considers a difference of images before and after sealing obtained from one static camera. By utilizing a difference of images, the proposed system shows very robust performance using a proposed simple depth checking algorithm for some contamination cases by oil with similar color with that of sealing and the total inspection system is simple and cheap to implement. According to the experiments conducted in a real car product line, the proposed inspection system shows better inspection performance and needs smaller implementation cost than three other previously proposed system working in current car sealing inspection systems.

An Application of Cognitive Task Analysis for the Evaluation of Human Performance on Inspection Tasks (인지적 작업분석에 의한 검사작업의 인간 수행도 분석)

  • Lee, Sang-Do;Kwack, Hyo-Yean
    • Journal of Korean Society for Quality Management
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    • v.23 no.3
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    • pp.69-83
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    • 1995
  • In a large number of literature on of inspection tasks, one of the most consistent findings is the existence of large and consistent differences among inspectors. It is possible that the individual difference is described by the difference of cognitive skills, because cognitive skills are required more than manual skills in inspection tasks. Therefore, a set of cognitive factors in human information processing may underly human performance in inspection tasks. In this study, a cognitive skill was described as the relative importance of the cognitive factors involved. A hierarchical task analysis and a fuzzy hierarchical analysis were used to represent how the importance of cognitive factors contribute to inspection performance. An experiment was conducted using the computer simulations of PCB inspection tasks. The results revealed that the subject group with better performance showed the importance weights of cognitive factors in the following rank; (attention, perception, judgement, classification, recognition)<(detection)$\ll$(memory). The results of the experiment can serve as a selection criterion for efficient inspection performance and the information of skilled learning for an inspection training program. The usefullness of a hierarchical task analysis and a fuzzy hierarchical task analysis for the analysis of cognitive tasks are also confirmed.

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A Study on the Risk Analysis of Construction Method (건축공법 내부 리스크 분석에 관한 연구)

  • 윤여완;양극영
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2002.11a
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    • pp.117-121
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    • 2002
  • The purpose of this study was to Identification the Risk of construction method to protect and reduce the risk of construction period. For this study we are using the pre and during construction period Inspection list. The inspection list was used by construction company for check a flaw of Construction field. So we rearrange the individual item of inspection list to match the Risk factor. This inspection list usually has the difference of importance because this list is not made by Method which is not focused on Method. Therefore, To find the difference of these importance, We surveyed this matter by doing interview of specialist group. To find the application of field and the possibility of measurement of Risk status, We tested Risk occurring frequency and it's strength by checking the level of Risk. The results of this study were as follows; Each Method Check List made out through the rearrangement of Construction Inspection list which used in construction company. To solve and compensate the matter which happened by changing the each Method Check List to each General Inspection List, we added the each Method Check List by checking the importance of check list of each process. By doing this, The Check List for finding Risk level of Method was created by using the check list of each Method.

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A Study on the Risk Analysis of Construction Method (건축공법 내부 리스크 분석에 관한 연구)

  • Yoon, Yer-Wan;Yang, Keek-Young
    • Journal of the Korea Institute of Building Construction
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    • v.2 no.4
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    • pp.131-135
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    • 2002
  • The purpose of this study was to Identification the Risk of construction method to protect and reduce the risk of construction period. For this study we are using the pre and during construction period Inspection list. The inspection list was used by construction company for check a flaw of Construction field. So we rearrange the individual item of inspection list to match the Risk factor. This inspection list usually has the difference of importance because this list is not made by Method which is not focused on Method. Therefore, To find the difference of these importance, We surveyed this matter by doing interview of specialist group. To find the application of field and the possibility of measurement of Risk status, We tested Risk occurring frequency and it's strength by checking the level of Risk. The results of this study were as follows; Each Method Check List made out through the rearrangement of Construction Inspection list which used in construction company. To solve and compensate the matter which happened by changing the each Method Check List to each General Inspection List, we added the each Method Check List by checking the importance of check list of each process. By doing this, The Check List for finding Risk level of Method was created by using the check list of each Method.

A report on the preparation of signaling equipment procedures for the periodic inspection (신호설비 정기검사 절차서 작성에 대한 보고)

  • Ko, Yang-Ok;Seo, Moon-Seog
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.623-629
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    • 2008
  • A periodic inspection for facilities in operation is an inspection that is carried out regularly, in which inspection cycles are drawn up, and it is a series of tests to determine if the condition of all the equipment is maintained, and to identify whether they are to be used or replaced. Reliability should be enhanced, without a breakdown, by preliminary inspection and regular checks for each equipment item installed for equipment maintenance. It was noticed that there was a slight difference for the same facility, and for each organization in terms of inspection cycles and methods while preparing procedures of periodic inspection checklist, inspection methods and cycles for a related organization. Therefore, this paper reviews the optimal methods of inspection procedures for Seoul Metro.

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Interval Scan Inspection Technique for Contact Failure of Advanced DRAM Process using Electron Beam-Inspection System

  • Oh, J.H.;Kwon, G.;Mun, D.Y.;Kim, D.J.;Han, I.K.;Yoo, H.W.;Jo, J.C.;Ominami, Y.;Ninomiya, T.;Nozoe, M.
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.12 no.1
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    • pp.34-40
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    • 2012
  • We have developed a highly sensitive inspection technique based on an electron beam inspection for detecting the contact failure of a poly-Si plugged layer. It was difficult to distinguish the contact failure from normal landing plugs with high impedance. Normally, the thermal annealing method has been used to decrease the impedance of poly-Si plugs and this method increases the difference of charged characteristics and voltage contrast. However, the additional process made the loss of time and broke down the device characteristics. Here, the interval scanning method without thermal annealing was effectively applied to enhance the difference of surface voltage between well-contacted poly-Si plugs and incomplete contact plugs. It is extremely useful to detect the contact failures of non-annealed plug contacts with high impedance.

Analysis of Inspection Ability of Panel Using BMPC Method

  • Shinji, Ohyama;Kim, Doh-Hyun
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.158.6-158
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    • 2001
  • A band function model paired comparison(BMPC) method is a kind of paired comparison methods. Considering that human has ambiguity, the BMPC method uses a monotonous increase function with the width as the human judgment characteristic. Since panel´s judgments do not always have enough response, it is very important to examine inspection abilities of each panel. In this study. We focus on the difference of band functions in each panel, which is the characteristic function of judgment in the BMPC method, and examine the method of obtaining panels inspection abilities. Three kinds of evaluation functions, "the dispersion of judgments", "the resolution", and "the difference of the judgments" are defined from Panel´s characteristic function of ...

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Measurement of Sound Speed Following the Fluid Temperature Using Acoustic Inspection Device

  • Jeon, E.S.;Kim, W.T.;Kim, I.S.;Park, H.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.30 no.3
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    • pp.207-211
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    • 2010
  • In this paper, the fluid AID(acoustic inspection device) was developed to measure SOS(speed of sound) since fluids used in most of industrial fields have different properties and its equipment is highly expensive. From AID developed, it is intended to get potentially the capability to distinguish the kind of fluid using the measurement by the SOS at various fields. In order to measure the sound speed of specific fluids, the measurement system and ultrasonic sensors are composed. The fluid used in the experimental work are soybean oil, glycerin, diesel oil and the error of time difference due to the container wall is extracted for preliminary experiment. As results, the variations of sound speed according to the temperature change of target fluid were analyzed and the polynomial equations were proposed.