• 품질경영학회지
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• 제31권2호
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• pp.183-193
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• 2003

A special cause producing temporary deviation in the underlying process can influence on process adjustment in responsive feedback control system. In this paper, the impact of special causes on the EWMA(Exponentially Weighted Moving Average) forecasts and the process adjustment that is based on the EWMA forecasts are derived. For some special causes with patterned type of contamination, the influence of the causes on the output process are explicitly investigated. A data set, contaminated by a special cause of level shift, is analyzed to evaluate the impact numerically.

• 품질경영학회지
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• 제32권2호
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• pp.201-211
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• 2004

Process adjustment is a complimentary tool to process monitoring in process control. Process adjustment directs on maintaining a process output close to a target value by manipulating another controllable variable, by which significant process improvement can be achieved. Therefore, this approach can be applied to the 'Improve' stage of Six Sigma strategy. Though the optimal control rule minimizes process variability in general, it may not properly function when special causes occur in underlying process, resulting in off-target bias and increased variability in the adjusted output process, possibly for long periods. In this paper, we consider a responsive feedback control system and the minimum mean square error control rule. The bias in the adjusted output process is investigated in a general framework, especially focussing on stationary underlying process and the special cause of level shift type. Illustrative examples are employed to illustrate the issues discussed.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2004년도 품질경영모델을 통한 가치 창출
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• pp.425-429
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• 2004

Process adjustment Is a complimentary tool to process monitoring in process control. Process adjustment directs on maintaining a process output close to a target value by manipulating another controllable variable, by which significant process improvement can be achieved. Therefore, this approach can be applied to the 'Improve' stage of Six Sigma strategy. Though the optimal control rule minimizes process variability in general, it may not properly function when special causes occur in underlying process, resulting in off-target bias and increased variability in the adjusted output process, possibly for long periods. In this paper, we consider a responsive feedback control system and the minimum mean square error control rule. The bias in the adjusted output process is investigated in a general framework, especially focussing on stationary underlying process and the special cause of level shift type. Illustrative examples are employed to illustrate the issues discussed.

• 대한산업공학회지
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• 제32권3호
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• pp.210-218
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• 2006

Traditional statistical process control (SPC) applied to discrete part industry in the form of control charts can look for and eliminate assignable causes by process monitoring. On the other hand, engineering process control (EPC) applied to the process industry in the form of feedback control can maintain the process output on the target by continual adjustment of input variable. This study presents controlling and monitoring rules adopted by variable sampling interval (VSI) to change sampling intervals in a predetermined fashion on the predicted process levels under integrated EPC and SPC systems. Twelve rules classified by EPC schemes(MMSE, constrained PI, bounded or deadband adjustment policy) and type of sampling interval combined with EWMA chart of SPC are proposed under IMA (1,1) disturbance model and zero-order (responsive) dynamic system. Properties of twelve control rules under three patterns of process change (sudden shift, drift and random shift) are evaluated and discussed through simulation and control rules for integrated VSI EPC and SPC systems are recommended.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2005년도 춘계공동학술대회 발표논문
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• pp.723-729
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• 2005

Traditional statistical process control(SPC) applied to discrete part industry in the form of control charts can look for and eliminate assignable causes by process monitoring. On the other hand, engineering process control(EPC) applied to the process industry in the form of feedback control can maintain the process output on the target by continual adjustment of input variable. This study presents controlling and monitoring rules adopted variable sampling interval(VSI) to change sampling intervals in a predetermined fashion on the predicted process levels for integrated EPC and SPC systems. Twelve rules classified by EPC schemes(MMSE, constrained PI, bounded or deadband adjustment policy) and type of sampling interval combined with EWMA chart of SPC are proposed under IMA(1,1) disturbance model and zero-order (responsive) dynamic system. The properties of twelve control rules under three patterns of process change(sudden shift, drift and random shift) are evaluated and discussed through simulation and control rules for integrated VSI EPC and SPC systems are recommended.

• Communications for Statistical Applications and Methods
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• 제19권3호
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• pp.395-403
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• 2012

Process adjustment, also called engineering process control(EPC), is applied to maintain process output close to a target value by manipulating controllable variables, but special causes may still make the process deviate from the target and result in significant costs. Thus, it is important to detect and mediate deviations as early as possible. We propose a one-step detection method, the moving search block(MSB), with which the time and type of a special cause can be identified in short periods. A modified control rule that can entertain the effects of the special cause is proposed. A numerical example is presented to evaluate the performance of the proposed scheme.

• 한국보육학회지
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• 제18권4호
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• pp.247-265
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• 2018

본 연구는 장애 유아 통합보육을 위한 교사 지원이 어린이집 교사의 교사 효능감에 미치는 영향을 알아보고자 하였다. 연구에는 서울과 경기 지역 4개 어린이집 12명의 어린이집 교사가 실험 집단에 선정되었고, 5개 어린이집 12명의 교사가 통제 집단에 선정되었다. 교사 지원은 교사 교육과 현장 관찰 및 자문, 온라인 자문을 통해 실시되었다. 교사 교육은 집단 교육을 통해 발달 영역의 이해, 교육과정 수정, 활동중심삽입교수, 협동 학습, 직접 교수, 장애 이해 교육, 행동 지원, 가족 지원 등에 대한 교육을 실시하고, 개별 교육을 통해 각 교사들의 장애유아 통합보육의 요구를 반영한 장애유아 보육의 실제에 대한 교육을 실시하고 자문을 제공하였다. 실험집단 어린이집 당 10회씩 현장 관찰 및 자문을 실시하였고, 이메일과 핸드폰 자문을 통해 교사들의 수업을 지원 하였다. 교사의 교사 효능감 변화를 측정하기 위해 사전-사후 검사 통제 집단 설계를 적용하였으며, 장애 통합에 대한 일반 교사의 교사 효능감 척도(Teachers' Efficacy in Inclusive Practices: TEIP)로 사전-사후 검사를 실시하였다. 연구 결과의 분석을 위해 두 집단 간 교사 효능감의 사전-사후 검사 간 차에 대해 두 독립표본 t 검정을 실시하였고, 결과 두 집단 간 교사 효능감과 하위 영역인 통합교육 효능감, 협력 효능감, 행동관리 효능감의 사전 사후 변화에 유의미한 차이를 보였다. 본 연구에서 장애 유아 통합보육 현장에서 즉각적인 피드백을 제공하고, 어린이집 교사들의 통합보육 전문성을 향상시키고, 교사들의 실제적 요구에 반응적이고, 장애 유아 통합의 다양한 변인을 반영하고, 참여자들 간의 대등한 협력적 관계를 강조한 교사 지원을 제공한 점이 연구 결과에 긍정적 영향을 주었다. 본 연구 결과는 장애 유아 통합보육 지원에 대한 연구가 부족한 현장의 실질적인 자료로 활용될 수 있을 것이다.