• 제목/요약/키워드: statistical process control

검색결과 570건 처리시간 0.04초

A Hybrid Approach to Statistical Process Control

  • Giorgio, Massimiliano;Staiano, Michele
    • International Journal of Quality Innovation
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    • 제5권1호
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    • pp.52-67
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    • 2004
  • Successful implementation of statistical process control techniques requires for operational definitions and precise measurements. Nevertheless, very often analysts can dispose of process data available only by linguistic terms, that would be a waste to neglect just because of their intrinsic vagueness. Thus a hybrid approach, which integrates fuzzy set theory and common statistical tools, sounds useful in order to improve effectiveness of statistical process control in such a case. In this work, a fuzzy approach is adopted to manage linguistic information, and the use of a Chi-squared control chart is proposed to monitor process performance.

Statistical Process Control Procedure for Integral-Controlled Processes

  • Lee, Jaeheon;Park, Cangsoon
    • Communications for Statistical Applications and Methods
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    • 제7권2호
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    • pp.435-446
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    • 2000
  • Statistical process control(SPC) and engineering process control(EPC) are two strategies for quality improvement that have been developed independently. EPC seeks to minimize variability by adjusting compensatory variables in order to make the process level close to the target, while SPC seeks to reduce variability by monitoring and eliminating causes of variation. One purpose of this paper is to propose the IMA(0,1,1) model as the in-control process model. For the out-of-control process model we consider two cases; one is the case with a step shift in the level, and the other is the case with a change in the nonstationarity. Another purpose is to suggest the use of an integrated process control procedure with adjustment and monitoring, which can consider the proposed process model effectively. An integrated control procedure will improve the process control activity significantly for cases of the proposed model, when compared to the procedure of using either EPC or SPC, since EPC will keep the process close to the target and SPC will eliminate special causes.

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통계적 공정관리와 공정조절의 통합을 위한 이론에 대한연구 (A study on the theory for Integrating of Statistical Process Control and Process Adjustmen)

  • 정해운
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2005년도 추계학술대회
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    • pp.493-504
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    • 2005
  • Statistical Process Control and Process Adjustment theory is gaining recognition in the process industries where the process frequently experiences a shift mean. This paper aims to study, the theory difference between Statistical Process Control and Process Adjustment in simple terms and presents a case study that demonstrates successful integration of Statistical Process Control and Process Adjustment theory for a product in drifting industry.

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담배 제조 공정의 통계적 관리시스템 개발 (Development of Statistical Process Control System for Tobacco Manufacturing Process)

  • 김영호;송정호
    • 한국연초학회지
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    • 제23권1호
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    • pp.53-59
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    • 2001
  • To decrease of deviations from target specifications and excessive variability around targe, we exclusively designed statistical process control system involving general manager and expert tool for cigarette manufacturing process. This system is a unique programming environment for the development of total process control software including various control charts according to data type and process capability analysis. Also this system includes the statistical analysis module to analyze defective causes immediately when inferior products are made and the module to offer regular reports. This system is customized considering the manufacture environment based on the opinions of workers.

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A Combined Process Control Procedure by Monitoring and Repeated Adjustment

  • Park, Changsoon
    • Communications for Statistical Applications and Methods
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    • 제7권3호
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    • pp.773-788
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    • 2000
  • Statistical process control (SPC) and engineering process control (EPC) are based on different strategies for processes quality improvement. SPC reduces process variability by detecting and eliminating special causes of process variation. while EPC reduces process variability by adjusting compensatory variables to keep the quality variable close to target. Recently there has been needs for a process control proceduce which combines the tow strategies. This paper considers a combined scheme which simultaneously applies SPC and EPC techniques to reduce the variation of a process. The process model under consideration is an integrated moving average(IMA) process with a step shift. The EPC part of the scheme adjusts the process back to target at every fixed monitoring intervals, which is referred to a repeated adjustment scheme. The SPC part of the scheme uses an exponentially weighted moving average(EWMA) of observed deviation from target to detect special causes. A Markov chain model is developed to relate the scheme's expected cost per unit time to the design parameters of he combined control scheme. The expected cost per unit time is composed of off-target cost, adjustment cost, monitoring cost, and false alarm cost.

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불명확한 공정정보 처리를 위한 퍼지-통계적 관리도의 개발 (Development of Fuzzy-Statistical Control Chart for Processing Uncertain Process Information)

  • 김경환;하성도
    • 한국정밀공학회지
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    • 제15권2호
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    • pp.75-80
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    • 1998
  • Process information is known to have the continuous distribution in many manufacturing processes. Generalized p-chart has been developed for controlling processes by classifying the information characteristics into several groups. But it is improper to describe continuous processes with the classified process informal ion, which is based on the classical set concept. Fuzzy control chart, has been developed for the control of linguistic data, but it is also based on the dichotomous notion of classical set theory. In this paper, fuzzy sampling method is studied in order to process the uncertain data properly. The method is incorporated with the fuzzy control chart. Statistical characteristics of the fuzzy representative value are utilized to device the fuzzy-statistical control chart. The fuzzy-statistical control chart is compared with the generalized p-chart and both the sensitivity to the process information distribution change pared robustiness against the noise on the process information of the fuzzy-statistical control chart are shown to be superior.

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MS-EXCEL과 Visual Basic으로 개발한 통계적 공정관리 소프트웨어 (Statistical Process Control Software developed by MS-EXCEL and Visual Basic)

  • 한경수;안정용
    • 품질경영학회지
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    • 제24권2호
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    • pp.172-178
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    • 1996
  • In this study, we developed a software for statistical process control. This software presents $\bar{x}$, R, CUSUM, EWMA control chart and process capability index. In this system, statistical process control methods are integrated into the automated method on a real time base. It is available in process control of specified type and can be performed on personal computer with network system.

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100 PPM 관리체제하의 실시간 공정관리 방안 (Real Time Process Control System under 100 PPM Management System)

  • 조남호;신숙현
    • 품질경영학회지
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    • 제25권1호
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    • pp.116-134
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    • 1997
  • The present automated manufacturing environment is very different when the classical statistical process control method based on batch processing were used. Therefore these must be replaced by automated statistical process control method. In this point of view, this paper intends to develop the automated statistical process control method which can be implemented in the present automated manufacturing environment. Specially this study developed the rules to identify the special causes of the manufacturing process in the aspect of the 100 PPM management, and a numerical example is demonstrated to verify the usefulness of these rules.

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통계적 공정 제어에 전문가 시스템의 적용에 관한 연구 (Applying an Expert System to Statistical Process Control)

  • 윤건상;김훈모;최문규
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1995년도 추계학술대회 논문집
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    • pp.411-414
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    • 1995
  • Statistical Process Control (SPC) is a set of methodologies for signaling the presence of undesired sources of variation in manufacturing processes. Expert System in SPC can serve as a valuable tool to automate the analysis and interpretation of control charts. In this paper we put forward a method of successful application of Expert System to SPC in manufacturing process.

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통계적 공정관리를 위한 주요 통계패키지의 비교 (Comparison of statistical packages useful for statistical process control)

  • 조신섭;신봉섭
    • 응용통계연구
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    • 제10권1호
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    • pp.29-36
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    • 1997
  • 본 비교연구는 국내에 소개되어 있는 통계패키지 중에서 기업의 품질경영(관리)이나 업무분석 등 공정관리와 연관된 패키지의 특성이나 기능등을 비교하였다. 일반적으로 많이 사용되고 있는 윈도우즈 버젼의 MINITAB, RS, SAS, SPSS가 고려되었다. 각 패키지의 일반적 특성과 가격 등을 알아보고 관리도 및 공정능력분석, 실험계획법과 다구찌 방법 등의 공정관리와 연관된 프로시져들을 중심으로 비교하였으며, 패키지를 선택할 때 고려하여야 할 기본적인 사항에 대하여도 언급하였다.

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