• 제목/요약/키워드: IS Process

검색결과 90,264건 처리시간 0.079초

유연공정계획 표현을 위한 객체지향형 페트리네트 모델 (Object-Oriented Petri Net Model for Representation of Flexible Process Plan)

  • 이경휘
    • 대한산업공학회지
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    • 제23권4호
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    • pp.669-686
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    • 1997
  • In this research, an object-oriented Petri net model for representing a flexible process plan is proposed, which is hierarchically multi-faceted for supporting planning, scheduling, and shop floor control functions. The multi-faceted process plan model consists of the following: a) an object model which represents on object-oriented data model, b) a static model which represents a process flow model with process alternatives, and c) a dynamic model which represents a process activity model with resources alternatives, of a flexible process plan. Petri nets allow the static and the dynamic process plan models to be represented in a unified formalism with an ease of model transformation. The multi-faceted process plan model suggested in this paper, is illustrated with a prismatic port in comprehensive detail.

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용접조건 개선으로 불량률 감소 -6시그마 프로세스를 중심으로- (Reducing the Rate of Defective to Improve a Welding Condition -Based on Six Sigma Process-)

  • 박진영
    • 품질경영학회지
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    • 제31권1호
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    • pp.123-131
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    • 2003
  • This paper considers a six sigma project for reducing the defects rate of the welding process in manufacturing firms. The project follows a disciplined process of five macro phases. define, measure, analyze, improve and control(DMAIC). The need of customers is used to identify critical to quality(CTQ) of project. And a process map is used to identify process input factors of CTQ. Four key process input factors are selected by using an input factor evaluation of teams; an interval of welding, an abrasion, an electric current and a moving freely. DOE is utilized for finding the optimal process conditions of the three key process input factors. Another one key input factor improved to welding machine. The six sigma level of defects rate becomes a 2.01 from a 1.61 at the beginning of the project.

마이크로 광 조형 기술을 이용하여 미세 유체 시스템을 개발하기 위한 가상 조립 공정의 개발 (Development of Virtual Assembly Process for the Fabrication of Micro-fluidic Systems Using Micro-stereolithography Technology)

  • 강현욱;이인환;조동우
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2004년도 춘계학술대회 논문집
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    • pp.304-309
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    • 2004
  • As it is difficult to construct a micro-fluidic system composed of micro-mixers, micro-channels and/or micro-chambers in a single process, an assembly process is typically used. The assembling and bonding of micro-parts, however, introduces other problems. In this work, a virtual assembly process was developed that can be used to design various micro-fluidic systems before actual fabrication commences. In the process, the information required for the micro-stereolithography process is generated automatically. Consequently, complex micro-fluidic systems can be fabricated in a single process, thereby avoiding the need for additional assembly or bonding processes. Using the developed process, several examples were fabricated.

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인공씨감자 생육상태 모니터링을 위한 화상처리 알고리즘 개발에 관한 연구 (A Study of Vision Algorithm Development for Growth Monitoring of Potato Microtubers)

  • 최재완;정광조;임선종;최성락;정혁;남호원
    • Journal of Biosystems Engineering
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    • 제23권4호
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    • pp.373-380
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    • 1998
  • The contribution of this paper is to provide the methods for the production automation of potato microtuber using the vision process in growth monitoring. The first method deals with computation for the growth density in the primary growth process. The second method addresses cognition process to identify the number and the volume of potato microtuber in secondary growth process. The third is to decide whether potato microtubers are infected by a virus or bacteria in growth process. The computation for the growth density in the primary growth process uses the method of Labeling. The second and third methods use template matching based on color patterns. With the developed method using vision process, this experiment is capable of discriminating weekly growth-rate in primary growth process, 85% cognition rate in secondary process and identifying whether there are infections. Therefore, we conclude that our experimental results are capable of growth monitoring for mass production of potato microtubers.

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EPD 신호검출에 의한 플라즈마식각공정의 이상검출 (Malfunction detection in plasma etching process using EPD signal trace)

  • 이종민;차상엽;최순혁;우광방
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.1360-1363
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    • 1996
  • EPD(End Point Detection) is used to decide etching degree of layer which must be removed at wafer etching process in plasma etching process which is one of the most important process in semiconductor manufacturing. In this thesis, the method which detects malfunction of etching process in real-time will be discussed. Several EPD signal traces are collected in normal plasma etching condition and used as reference EPD signal traces. Critical points can be detected by applying differentiation and zero-crossing techniques to reference EPD signal. Mean and standard deviation of critical parameters which is memorized from reference EPD signal are calculated and these determine the lower and higher limit of control chart. And by applying statical control chart to EPD signals which are collected in real etching process malfunctions of process are detected in real-time. By means of applying this method to the real etching process we prove our method can accurately detect the malfunction of etching process and can compensate disadvantage of current industrial method.

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하이드로 임베딩시 연결요소의 회전을 통한 체결력 개선 연구 (Improvement of Connection Force in Hydro-Embedding Process Through the Rotational Piercing of the Connection Element)

  • 김봉준;김동규;김동진;문영훈
    • 대한기계학회논문집A
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    • 제30권12호
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    • pp.1503-1508
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    • 2006
  • To increase the applicability and productivity of hydroforming process, hydro-embedding process was developed by combining the hydro-forming process with embedding process simultaneously. It is necessary in the automotive parts to form hollow bodies with connection elements which combine one part with another. The hydro-embedding process is embedding the connection element hydraulically during the operating steps of the hydroforming. In this study, technique of rotational piercing is added on the existing hydro-embedding to increase the connection force of hydro-embedded element. To estimate the feasibility of new trial process, integrated researches on the hydro-embedding process technology have been performed by analyzing the deformed mode of the tubes and the optimal process parameters for various shapes of the connection elements.

따라 말하기 과제에서의 음향적 처리와 음운적 처리 (Acoustic and phonological processes in the repetition tasks)

  • 유세진;이경민
    • 한국인지과학회:학술대회논문집
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    • 한국인지과학회 2010년도 춘계학술대회
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    • pp.42-47
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    • 2010
  • Speech shares acoustic features with other sound-based processing, which makes it difficult to distinguish phonological process from acoustic process in speech processing. In this study, we examined the difference between acoustic process and phonological process during repetition tasks. By contrasting various stimuli in different lengths, we localized neural correlates of acoustic process within bilateral superior temporal gyrus, which was consistent with the previous studies. The activated patterns were widely overlapped between words and pseudowords, i.e., contents-free. In contrast, phonological process showed left-lateralized activation in middle temporal gyrus located at anterior temporal areas. It implies that phonological process is contents-specific as shown in our previous study, and at the same time, more language-specific. Thus, we suggest that phonological process is distinguished from acoustic process in that it is always accompanied with the obligatory access to available phonological codes, which can be an entry of the mental lexicon.

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Business Process Change Design from Decision Model Perspective

  • Han, Hyun-Soo
    • Management Science and Financial Engineering
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    • 제9권2호
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    • pp.21-45
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    • 2003
  • Various organizational factors effect successful implementation of IT enabled business transformation. Among them, the most critical success factor is deemed to overcoming change management problem. Lots of studies have been made on implementation methodologies and business process formalizations to encourage organizational members to accept new business process changes. However, the logic of process redesign still depends on qualitative problem solving techniques mostly depending on basically human intuition such as brainstorming, cause-and-effect analysis, and so on. In this paper, we develop algorithmic procedure applicable to designing various business process changes such as process automation, business process resequencing, and more radical process integration. The framework is employed from dynamic programming approach in the literature, which is based on the decision making paradigm of organizations to abstract business processes as quantitative decision models. As such, our research can fill the gap of limited development of theory based analytic methodologies for business process design, by providing objective rationale to reach the consensus among the organizational members including senior management.

감도분석에 의한 제조공정연구 (A Study on the manufacturing process using the sensitivity analysis of stochastic network)

  • 박기주
    • 산업경영시스템학회지
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    • 제24권63호
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    • pp.65-77
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    • 2001
  • A more technical perspective is needed in estimating the effect of the Manufacturing Process for improving the Productivity, there are many statistical evaluation methods, convenience sampling, frequencies, histogram, QC seven tools, control chart etc. It is more important for the companies to use six sigma to reduce defective and improve the process control than the technical definition as a disciplined quantitative approach for improvement of process control and a new way of quality innovation. Process network analysis is a technique which has the potentiality for a wide use to improve the manufacturing process which other techniques can't be used to analyze effectively. It has some problems to analyze the process with feedback loops. The branch probabilities during quality inspections depend upon the number of times the product has been rejected. This paper presents how to improve the manufacturing process by statistical process control using branch probabilities, Moment Generating Function(MGF) and Sensitivity Equation.

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수리 가능 시스템의 신뢰성 분석 절차 및 사례 연구 (Reliability Analysis Procedures for Repairable Systems and Related Case Studies)

  • 이성환;염봉진
    • 한국군사과학기술학회지
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    • 제9권2호
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    • pp.51-59
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    • 2006
  • The purpose of this paper is to present reliability analysis procedures for repairable systems and apply the procedures for assessing the reliabilities of two subsystems of a specific group of military equipment based on field failure data. The mean cumulative function, M(t), the average repair rate, ARR(t), and analytic test methods are used to determine whether a failure process follows a renewal or non-renewal process. For subsystem A, the failure process turns out to follow a homogeneous Poisson process, and subsequently, its mean time between failures, availability, and the necessary number of spares are estimated. For subsystem B, the corresponding M(t) plot shows an increasing trend, indicating that its failure process follows a non-renewal process. Therefore, its M(t) is modeled as a power function of t, and a preventive maintenance policy is proposed based on the annual mean repair cost.