• 제목/요약/키워드: Process

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네트 모델을 이용한 대체 공정 계획 생성 (Generation of Alternative Process Plan by Net Model)

  • 박지형;박면웅;강민형
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1994년도 추계학술대회 논문집
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    • pp.743-747
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    • 1994
  • A process planning system that generates alternative process plans offers multiple process plans for a part, thereby provides the flexibility to cope with the changes in shop floor status. In this paper, we introduce the concept of process net as a model for the generation of alternative process plans. We also show the usefulness of process net model by implementing the developed system to generate alternative process plans for rotational parts.

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붓스트랩 $C_{pp}$ 다공정 수행분석차트 (Bootstrap $C_{pp}$ Multiple Process Performance Analysis Chart)

  • 장대흥
    • 품질경영학회지
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    • 제38권2호
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    • pp.171-179
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    • 2010
  • Pearn et al.(2002) supposed the $C_{pp}$ multiple process performance analysis chart. This chart displays multiple processes with the process variation and process departure on one single chart. But, this chart can not display the distribution of the process variation and process departure and is inappropriate for processes with non-normal distributions. With bootstrapping method, we can display the distribution of the process variation and process departure on the $C_{pp}$ multiple process performance analysis chart.

A Study on Process Safety Incident Precursors to Prevent Major Process Safety Incidents in the Yeosu Chemical Complex

  • Baek, Seung-Hyun;Kwon, Hyuck-Myun;Byun, Hun-Soo
    • Korean Chemical Engineering Research
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    • 제56권2호
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    • pp.212-221
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    • 2018
  • Process safety incidents and loss events can be prevented if we identify and adequately take measures on process safety incident precursors in a timely manner. If we look into and take action against the process safety hazard factors causing the incident in the refinery and petrochemical plant, major process safety incidents can be prevented through eliminating or decreasing hazardous factors. We conducted a survey for the major process safety incident precursor to look specifically into the potential process safety hazardous factors of refineries and petrochemical plants in the Yeosu chemical complex. A self-assessment checklist, which was published by Center for Chemical Process Safety "Recognizing catastrophic incident warning signs in the process industry" on major incidents warning sign, was used for the survey. Through this survey, the major process safety incident leading indicators in the process industry were found by process safety management elements, and each site and/or facility can use these leading indicators for activities for process safety incident prevention. In addition, we proposed action items required to eliminate the root cause of those process safety incident leading indicators.

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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기대손실을 이용한 다변량 공정능력지수 (A Multivariate Process Capability Index using Expected Loss)

  • 정영배
    • 산업경영시스템학회지
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    • 제28권4호
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    • pp.116-123
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    • 2005
  • The traditional process capability indices Cp, Cpk, Cpm, $Cpm^+$ have been used to characterize process performance on the basis of univariate quality characteristics. Cp, Cpk consider the process variation, Cpm considers both the process variation and the process deviation from target and Cpm+ considers economic loss for the process deviation from target. In manufacturing industry, there is growing interest in quantitative measures of process variation under multivariate duality characteristics. The multivariate process capability index incorporates both the process variation and the process deviation from target or considers expected loss caused by the process deviation from target. This paper proposes multivariate capability index based on the expected loss derived from multivariate normal distribution.

공정능력지수와 비공정능력지수의 차이분석 (Analysis of Difference Between the Process Capability Indices and the Process Incapability Indices.)

  • 양정문;이보근;김정자
    • 산업경영시스템학회지
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    • 제21권45호
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    • pp.347-356
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    • 1998
  • For assessing the capability of a process, the quantification of process location and variation is central to understanding the quality of units produced from the manufacturing process. Conventional process capability indices is insufficient to drive out the information for process condition, furthermore it is very difficult to evaluate the process capability accurately when the target value is not consistent with the center of specification, and/or the shape of distribution is changed, but the process incapability indices is enable to provide more detailed information to evaluate the process capability by dividing information about the process mean and variance. In this paper, we have a brief review and comparison about these indices, provide an understanding of the relationships between the process capability indices and the incapability indices. And we explore the strengths and weakness of these indices as they apply to normally distributed process, and to examine the effect that non-normality has on these indices.

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데이터마이닝을 이용한 공정변수 확인 및 공정개선 (Identification Process Variables and Process Improvement Using Data Mining)

  • 정영수;강창욱;변성규
    • 산업경영시스템학회지
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    • 제28권3호
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    • pp.166-171
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    • 2005
  • With development of the database, there are too many data on process variables and the manufacturing process for the traditional statistical process control methods to identify the process variables related with assignable causes. Data mining is useful in this situation and provides variety of approaches for improving the process. In this paper, we applied control charts to monitor the process and if assignable causes are detected, then we applied the SVM technique and the sequence pattern analysis to find out the process variables suspected. These techniques made possible to predict the behavior of process variables. We illustrated our proposed methods with real manufacturing process data.

UML 기반 객체 지향 개발을 위해 ISO 12207을 조정한 객체지향 프로세스 (ISO12207 Tailored Object-Oriented Process for UML Based Object-Oriented Development)

  • 이상준;김병기
    • 한국정보처리학회논문지
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    • 제6권10호
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    • pp.2680-2692
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    • 1999
  • Software quality is classified by quality of process and product. In experience of Quality Management, it is known that quality level of product as it depends on goodness and badness of process and organization. As a result, improvement of software process has been important subject. According as this trends, ISO 12207 is publicated as standard of software life cycle process by ISO. For UML based object oriented development process, it is necessary that we should research detailed definition of activity and task of ISO 12207 process which is added, deleted or tailored in according to organization and project characteristics. In this thesis, by according with ISO 12207 software life cycle process, UML based object oriented development process is proposed. This process is composed of 7 steps and 19 activities including development phase, activity and product to improve quality of reliability. Usefulness of object oriented process for improvement of software quality is proved at three ways, which are comparative analysis of process characteristics, SPICE process evaluation and SPICE rick analysis.

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소프트웨어 프로세스 개선을 통한 프로세스 수준과 성과 향상 방안 (A Study on the Elevation of Software Process Level and Performance through Software Process Improvement)

  • 문송철;김현수
    • 정보처리학회논문지D
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    • 제13D권1호
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    • pp.75-86
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    • 2006
  • 소프트웨어 프로세스는 개선되는 추세에 있으나, 그 범위나 접근방법이 제한적인 것이 현실이다. 따라서 소프트웨어 프로세스 기반구조를 구축하고 구축된 기반구조를 개선해 나가며 지속적으로 관리, 활용해야 한다. 그러한 기반 구조를 통하여 소프트웨어 프로세스 수행 능력 수준을 높임과 아울러 조직의 프로세스 품질 문화가 합치되어 더욱 소프트웨어 프로젝트 품질과 조직의 프로세스 성과에 향상을 미칠 수 있는지 연구되었다. 연구 결과, 소프트웨어 사업자들이 지금까지 구축된 기술 기반구조와 함께 소프트웨어 프로세스 관리 및 조직 기반구조를 구축하여 근본적인 소프트웨어 프로세스 기반구조를 갖추는 것이 무엇보다 중요하며, 소프트웨어 프로세스 기반구조의 수준을 높이며 지속적인 관리활동으로 이어져 진행될 때, 프로세스 수행 능력 수준이 향상되고 프로세스 수행 능력 수준 향상과 더불어 프로세스 품질 문화 수준과의 적합을 통하여 프로세스 수준과 성과가 향상되는 것으로 분석되었다.

지속적 프로세스 개선을 위한 성과 중심의 생애 주기 기반 비즈니스 프로세스 관리 프레임워크 (A Life Cycle-Based Performance-Centric Business Process Management Framework For Continuous Process Improvement)

  • 한관희
    • 한국콘텐츠학회논문지
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    • 제17권7호
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    • pp.44-55
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    • 2017
  • 최근에 많은 기업들이 기업 목표를 달성하기 위해 프로세스 혁신이나 개선을 지속적으로 꾀하고 있으며, 이를 지원하는 도구로 BPM (Business Process Management)이 많이 도입되고 있다. BPM의 생애 주기는 프로세스 진단, (재)설계 및 실행으로 이루어지는데, 모든 BPM 활동들은 성과 척도와 밀접한 관련을 갖고 운영되어야 한다. 본 논문의 목적은 프로세스 기반 성과 측정 모델과 통합된 생애 주기 기반 BPM 프레임워크를 제안하는 것이다. 제안 프레임워크에서는 BPM 전 생애 주기 동안 비즈니스 프로세스와 성과 척도가 체계적인 상관관계를 가지고 밀접하게 운영된다. 기업의 혁신이나 개선 담당자들은 제안 프레임워크를 사용하여 프로세스 진단 단계에서는 기업 성과에 가장 영향을 주는 프로세스를 용이하게 확인할 수 있고, 프로세스 (재)설계 단계에서는 새롭게 설계된 프로세스의 성과를 측정할 수 있으며, 프로세스 실행 단계에서는 성과 척도를 모니터하여 비즈니스 활동 들을 조정할 수 있게 된다.