• 한국시뮬레이션학회논문지
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• 제19권1호
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• pp.1-11
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• 2010

K 회사는 국내외 반도체 제조업체의 주문에 의해 반도체 패키지 제품을 생산 공급하는 기업이다. 생산 공정은 Die Sawing, 조립, 테스트로 구성된 기계중심의 조립라인 형태를 따르고 있다. 본 논문은 K 회사의 공정분석을 토대로 패키지 공정의 생산량을 늘리기 위한 3가지 방안을 제안하고, 이들을 실제 자료를 이용한 시뮬레이션 모델을 통해 평가하는 사례연구를 다룬다. 3가지 방안은 병목공정에 기계 추가에 의한 라인균형, 제품의 그룹 스케쥴링, 비병목공정에서 작업자의 재배치이다. 시뮬레이션 평가결과, 3가지 방안을 혼합 적용하는 경우에 2.8%의 납기위반율 감소 효과와 함께 17.3%의 가장 높은 일일 생산량 증가를 보여 주는 것으로 나타났다. 3가지 방안의 혼합 적용하는 경우의 투자회수기간은 1.37년으로 매우 짧게 구해졌다.

• 산업공학
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• 제7권3호
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• pp.125-135
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• 1994

This thesis reports the development of a Computer-Aided Process Planning system for rotational parts. The developed system ultimately generates process plans for rotational parts through a knowledge-base. The knowledge-base and decision-making algorithms are represented by Pascal computer programming language. We have developed a process planning system which adjusts the sequence of processes by itself to ensure the quality of the parts. This system generates more detailed job sequence and descriptions than other well-known process planning systems. We present realistic and efficient process plans through the integration of process planning and scheduling. This system optimizes flow time of parts by decreasing the number of machine set-ups.

• 산업경영시스템학회지
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• 제14권24호
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• pp.193-198
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• 1991

Is this paper the selection of a set of process plans is considered for a flexible manufacturing systems. This problem arises in the metal working industry when numerical controlled(N/C) machines are used to manufacture parts. In this paper a new concept to reduce the size of problem is proposed. A corresponding Integer programming model is formulated. The model formulated is to minimize corresponding manufacturing cost and minimize the number of tools and auxiliary devices such as fixtures, grippers, and feeders.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.729-730
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• 2011

• 대한산업공학회지
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• 제5권1호
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• pp.53-57
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• 1979

The concept of AOQL in designing Dodge's continuous sampling plans is modified to include probabilistic consideration reflecting the prior knowledge about the process average fraction defectives, and a new design criterion called AOQL, which eliminates some of the drawbacks of the AOQL criterion is proposed. AOQL, approach provides more economical sampling plans in many cases, and can be used even when only limited amount of prior information is available.

• 품질경영학회지
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• 제8권2호
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• pp.3-14
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• 1980

This paper is concerned with the design of an appropriate sampling plan or stopping rule and the construction of estimate for the estimation of process or lot fraction defective. Various sampling plans which are well known or have potential applications are unified into a generalized sampling plan. Under this sampling plan sufficient statistic, probability distribution, moment, and minimum variance unbiased estimate are obtained. Results for various sampling plans can be derived as special cases. Then, under given parameter values, the relative efficiencies of the various sampling plans are compared with respect to expected sample sizes and variances of estimates.

• 대한산업공학회지
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• 제22권4호
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• pp.719-739
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• 1996

A common control model used to implement computer integrated manufacturing(CIM) is based on the hierarchical decomposition of the shop floor activities, in which supervisory controllers are responsible for all the interactions among subordinates. Although the hierarchical control philosophy provides for easy understanding of complex systems, an emerging manufacturing paradigm, agile manufacturing, requires a new control structure necessary to accommodate the rapid development of a shop floor controller. This is what is called autonomous agent-based heterarchical control. As computing resources and communication network on the shop floor become increasingly intelligent and powerful, the new control architecture is about to come true in a modern CIM system. In this paper, heterarchical control is adopted and investigated, in which a controller for a unit of device performs three main functions - planning, scheduling and execution. Attention is paid to the planning function and all the detailed planning activities for heterarchical shop floor control are identified. Interactions with other functions are also addressed. In general, planning determines tasks to be scheduled in the future. In other words, planning analyzes process plans and transforms process plans into detailed plans adequate for shop floor control. Planning is also responsible for updating a process plan and identifying/resolving replanning activities whether they come from scheduling or execution.

• 품질경영학회지
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• 제25권3호
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• pp.22-38
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• 1997

In a traditional sequential acceptance sampling plan, it is assumed that the sampled items are independent each other. In this paper, stochastically dependent sequential acceptance sampling plans are dealt when there exists dependency between sampled items. Monte-Calro algorithm is used to find the acceptance and rejection probabilities of a lot. The number of defectives for the test to be accepted and rejected in probability ratio sequential test can be found by using these probabilities. The formula for measures of performance of these sampling plans is developed. Type I and II error probabilities are estimated by simulation. This research can be a, pp.ied to sequential sampling procedures in place of control charts where there is a recognized and necessary dependency during the production processes. Also, dependent multiple acceptance sampling plans can be derived by extending this sequential sampling procedure. As a numerical example, a Markov dependent process model is given, and the characteristics of the sampling plans are examined according to the change of the dependency factor.

• 산업경영시스템학회지
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• 제11권17호
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• pp.67-80
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• 1988

This study is concerned with the comparison of two time homogeneous Poisson processes. Traditionally, the methods of testing equality of Poisson processes were based on the binomial distribution or its normal approximations. The sampling plans used in these methods are to observe the processes concurrently over a predetermined time interval, possibly different for each process. However, when the values of the intensities of the processes are small, inverse type sampling plans are more appropriate since there may be cases where only a few or even no events are observed in the predetermined time interval. This study considers 9 inverse type sampling plans for the comparison of two Poisson processes. For each sampling plans considered, critical regions and the design parameters of the sampling plan are determined to guarantee the significance level and the power at some values of the alternative hypothesis. The Problem of comparing of two Weibull processes are also considered.

• 한국주거학회논문집
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• 제8권1호
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• pp.23-35
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• 1997

The purpose of this study is to analyze the original plans of the Railway official residence and process of the transfiguration of those plans based on the transition of social-culture, using 54 houses which were built from 1920 to 1945 in Taegu-Kyoungbuk province. In addition, this study was carried out by means of research on the form and pattern, and visual anthropological method by photograph and direct observation. The results of this study are as follows : 1) The original plans of Railway official residences were composed of the entrance hall, TADAMI Rooms, bathroom, toilet and HUSMA(wooden sliding doors). 2) After 1945, the room, kitchen, toilet of Japanese style had been trasfiguerated to Korean traditional style. 3) Since 1980's, those of Korean traditional style has been trasfigurated to the livingroom, dinningroom, entrance hall and etc. of western style.