• Communications for Statistical Applications and Methods
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• v.16 no.3
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• pp.429-436
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• 2009

This paper considers the integrated process control procedure for detecting special causes in an IMA(1,1) process that is being adjusted automatically after each observation using a minimum mean squared error adjustment policy. When the control chart signals after the occurrence of a special cause, the special cause will be detected and eliminated from the process by the rectifying action. However, when the elimination of the special cause costs high or is not practically possible, an alternative action is to readjust the process with appropriately modified adjustment scheme. In this paper, we propose the readjustment procedure after having a true signal, and show that the use of the readjustment can reduce the deviation of a process from the target.

• Journal of the Korean Data and Information Science Society
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• v.21 no.5
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• pp.841-852
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• 2010

An integrated process control (IPC) procedure is a scheme which simultaneously applies the engineering control procedure (EPC) and statistical control procedure (SPC) techniques to reduce the variation of a process. In the IPC procedure, the observed deviations are monitored during the process where adjustments are repeatedly done by its controller. Because the effects of the noise, the special cause, and the adjustment are mixed, the use and properties of the SPC procedure for the out-of-control process are complicated. This paper considers efficiency of EWMA charts for detecting special causes in an ARMA(1,1) noise model with a minimum mean squared error adjustment policy. And we propose the readjustment procedure after having a true signal. This procedure can be considered when the elimination of the special cause is not practically possible.

• Journal of the Korean Data and Information Science Society
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• v.22 no.6
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• pp.1123-1135
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• 2011

This paper considers the multivariate integrated process control procedure for detecting special causes in a multivariate IMA(1, 1) process. When the multivariate control chart signals, the special cause will be detected and eliminated from the process. However, when the elimination of the special cause costs high or is not practically possible, an alternative action is to readjust the process with approximately modified adjustment scheme. In this paper, we propose the readjustment procedure after having a true signal, and show that the use of the readjustment can reduce the deviation of a process from the target.

• Journal of KIISE:Databases
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• v.30 no.2
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• pp.184-196
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• 2003

Mobile transactions updating spatial objects are long transactions that can update independently local objects of mobile clients during disconnection. Validation based protocols that are well known to be appropriate for mobile transactions are required to abort a conflicted transaction in order to keep data consistent. Since abortion leads to cancel of all of tile updates, it is not desirable to use the abortion for resolving conflicts of mobile transactions. In this paper, we propose a reprocessing transaction model to resolve the update conflicts between mobile transactions without aborting them. We also design a mobile transaction server to support the reprocessing transaction and build a prototype of a mobile field system. The reprocessing transaction is a subtransaction of a newly committed mobile transaction and re-executes only conflicted objects with foreign conflicted objects. We also introduce a progressive reprocessing scheme to expose non-conflicted objects of the mobile transaction to other transactions in order to reduce starvation of reprocessing transactions.

• Journal of the Korean Data and Information Science Society
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• v.24 no.6
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• pp.1275-1283
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• 2013

This paper considers the multivariate integrated process control procedure for detecting special causes in a multivariate IMA(1, 1) process. When the multivariate control chart signals, the special cause will be detected and eliminated from the process. However, when the elimination of the special cause costs high or is not practically possible, an alternative action is to readjust the process with approximately modified adjustment scheme. In this paper, we estimate parameters in the readjustment procedure after having a true signal in the multivariate integrated process control.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.3
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• pp.310-315
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• 1996

엔진 배기가스의 동력과 유량이 배기행정의 직전 단계에서 관찰되었다. 배기가스 양을 적당히 조정함으로써 터보 과급의 입구 압력을 증가시킬 수 있었으며 엔진의 흡기, 소기 및 배기과정에서 가스질량과 엔진의 동력, 그리고 터보과급 효과도 감소하였다. 터보 과급장치를 기하학적으로 적절화시킴으로써 싸이클의 동기화 및 동력의 효율이 고려된 열교환 과정의 효율 기준도 제기되었으며 디젤엔진의 연소싸이클을 재수정하는 과정과 터빈의 동역학적 특성도 제시되었다.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10a
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• pp.202-204
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• 2001

무선이동 단말기가 발전함에 따라 GPS등의 측량 장치를 이용하여 현장에서 무선이동 단말기의 공간 데이터를 수정한 후에 수정된 공간 데이터를 무선 네트워크를 통하여 즉시 GIS 서버에 반영할 수 있게 되었다. 기존의 비관적 기법 기반의 트랜잭션 모델을 이용하는 경우에 잠금 충돌이 발생하면 충돌하는 모바일 트랜잭션들이 오랜 기간 동안 온라인 상태로 대기하는 문제가 있다. 또한 낙관적 기법 기반의 트랜잭션 모델을 이용할 경우에 변경 충돌(conflict)이 발생하면 현장에서 수행했던 모든 수정 작업을 취소하고 새로 공간 데이터 수정 작업을 재수행해야 하는 문제가 있다. 이 논문에서는 낙관적 기법에 기반한 모바일 트랜잭션 모델을 제시한다. 이 모델은 영역 잠금을 이용하여 트랜잭션 시작시 변경 의도를 표시한다. 그리고 완료 작업 수행시에 잠금을 이용하여 변경 충돌 검사를 한다. 변경 충돌이 발생하면 변경 충돌 해소를 위하여 해당 트랜잭션을 대기시키고 충돌이 발생한 부분에 대하여 사용자가 재수정 할 수 있도록 한다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.04a
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• pp.755-755
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• 1995

• Proceedings of the Korean Vacuum Society Conference
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• 2006.02a
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• pp.55-55
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• 2006

• Proceedings of the Korean Vacuum Society Conference
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• 2006.02a
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• pp.50-50
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• 2006