• 품질경영학회지
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• 제33권1호
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• pp.22-31
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• 2005

With the common objective to improve process productivity and product quality, statistical process control (SPC) and engineering process control (EPC) have been widely used in the discrete-parts industry and the process industry, respectively. The major focus of SPC is on process monitoring, while that of EPC is on process adjustment. The emergence of the hybrid industry necessitates a synergistic combination of the two methods for an effective process control. This paper investigates the existing studies on SPC, EPC, and the integration of the two methods. This paper also presents future research issues in this field.

• 한국건설관리학회논문집
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• 제1권4호
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• pp.74-81
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• 2000

대부분의 건설현장에서 기후에 대한공기산정은 정확한 자료 없이 현장관리자의 경험과 직관에 의해 일률적인 작업불가능일수를 정함으로써 잦은 공기 조정으로 인한 경제적 손실은 물론 공사 주체들간의 이해관계에서도 많은 문제점을 안고 있다. 따라서 본 연구는 공기에 영향을 미치는 기후를 요소별로 분석하고 가상기후 시뮬레이션을 실시하여 공기산정과 연계함으로써 공정표 작성 시 현장관리자들의 효율적인 공기산정을 위한 의사결정 지원모델을 제시하고, 기대 효과는 다음과 같다. (1) 제한된 과거(1990년-1999년) 기후자료를 요소별로 분석함으로써 단위공종에 대한 기후요소의 영향을 과학적인 방법으로 자료를 제공하였다. (2) 공정계획 시 단위공종에 각 기후요소별로 인자를 추가함으로써 불확실한 기후에 대한 사전 공정계획의 효율성 제고가 기대된다. (3) 기존의 현장관리자들의 경험적이고 직관적인 기후에 대한 대처를 확률분포를 이용한 통계적 처리에 의해 공기산정에 관한 신뢰성 있는 의사결정이 가능하게 되었다. 본 연구에서 제안한 공기산정 의사결정 지원모델은 공정계획 입안 시 불확실한 기후에 대한 과학적인 의사결정에 도움이 될 것이다.

• 한국산업정보학회논문지
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• 제4권3호
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• pp.71-78
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• 1999

이 논문은 영상처리기법을 이용하여 자동차 엔진 조림공정에 대한 통합적인 자동검사시스템의 개발에 관한 연구이다. 본 시스템은 머신비전에 의한 검사데이터를 통계적 공정관리시스템으로 직접 입력이 가능하며, 이러한 특성은 품질 이상이나 공정에 문제가 발생하였을 때 즉각적인 수정 조치가 가능한 기술이다. 검사부분에 대한 영상처리는 PC 내부에 설치되어 있는 IVP-150 머신비전 보드에 의하여 이루어지며, 품질요소를 정확히 확인하기 위해 템플리트 매칭 기술이 적용되었다. 본 시스템을 생산현장에 적용한 결과, 잡음이나 영상의 삐뚤어짐 흑은 방향성 등의 문제에도 적응력이 강함이 입증되었다.

• 대한기계학회논문집A
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• 제24권4호
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• pp.811-823
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• 2000

In design and manufacturing airframe structures which are composed of a lot of sub-assemblies and large complex profile shapes it is difficult to reduce so called hardware variations. Accordingly cost increasing factors for manufacturing airframe parts are much more than other machine parts because of the variability of fabricated details and assemlies. To improve cost and quality, accurate assembly methods and DPD techniques are proposed in this paper which are based upon using CAD/CAM techniques, the concept of KC's and the coordinated datum and index throughout the design, tooling, manufacturing and inspection. The proposed methods are applied to produce fuselage frame assemblies and related engineering aspects are described regarding the design of parts and tools in the context of concurrent digital definition. First articles and consequent mass production of frame assemblies shows a great improvement of the process capability ratio from 0.7 by the past processes to 1.0 by the proposed methods in addition to the cost reduction due to the less number of tools, reduced total assembly times and the space compaction needed by massive inventory. The need to achieve better Cpk, however, and future studies to be investigated will be addressed briefly.

• 품질경영학회지
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• 제27권4호
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• pp.256-265
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• 1999

In this paper, we Present the implementation of statistical process control software by using XLISP-STAT which is a kind of object oriented language under Windows environment. This software can be used to generate the graphic objects for various control charts, histogram and plots using the full-down menu system. This software can also be used to calculate control limits, process capability indices and test procedures for normality.

• 품질경영학회지
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• 제31권3호
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• pp.126-135
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• 2003

A basic assumption in standard applications of control charts is that the observations are statistically independent. However, this assumption is often violated from processes in many industries. The presence of autocorrelation has a serious impact on the performance of control charts, causing a dramatic increase in the frequency of false alarms. This paper considers a process in which the observations can be modeled as a first order autoregressive(AR(1)) process, and develops (equation omitted) charts with the variable sample size(VSS) scheme for monitoring the mean of this process.

• 한국산업정보학회논문지
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• 제1권1호
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• pp.111-125
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• 1996

This paper presents a statistical process control(SPC) system in the electronic parts manufacturing process. In this system, an SPC method is integrated into the automated inspection technology on a real time base. It shows how the collected data can be analyzed with the SPC to provide process information. also presented are stuided of subpixel image processing technology to improve the accuracy of parts mearements , and the cumulative-sum(CUSUM) control chart for fraction defectives.An application of the developed system to connector manufacturing process as a part of computer integrated manufacturing (CIM) is presented.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2006년도 춘계학술대회
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• pp.313-318
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• 2006

Many control charting methods for both i.i.d and autocorrelated data can be viewed as charting the output of a linear filter applied to the process data. We propose a generalization of this concept, in which the filter parameters are optimally selected to minimize the out-of-control ARL while constraining the in-control ARL to some desired value. A number of interesting characteristics of the optimal fitters are discussed.

• 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.

• 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.