• 산업경영시스템학회지
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• 제27권4호
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• pp.141-146
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• 2004

This research considers the problem of scheduling jobs on unrelated parallel machines with a common due date. The objective is to minimize the total absolute deviation of job completion times about the common due date. This problem is motivated by the fact that a certain phase of printed circuit board manufacturing and other production systems is bottleneck and the processing speeds of parallel machines in this phase are different for each job. A zero-one integer programming formulation is presented and two dominance properties are proved. By these dominance properties, it is shown that the problem is reduced to asymmetric assignment problem and is solvable in polynomial time.

• 산업경영시스템학회지
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• 제27권4호
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• pp.42-48
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• 2004

This paper concerns on a multiprocessor task scheduling problem with precedence relation, in which each task requires several processors simultaneously. Meta-heuristic generally finds a good solution if it starts from a good solution. In this paper, a tabu search is presented to find a schedule of minimal time to complete all tasks. A modified tabu search is also presented which uses a new initial solution based on the best solution during the previous run as the new starting solution for the next iteration. Numerical results show that a tabu search and a modified tabu search yield a better performance than the previous studies.

• 산업경영시스템학회지
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• 제23권56호
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• pp.9-18
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• 2000

This paper considers the problem of two-machine, M-parallel flow shop scheduling to minimize makespan, and proposes a series of heuristic algorithms and a branch and bound algorithm. Two processing times of each job at two machines on each line are identical on any line. Since each flow-shop line consists of two machines, Johnson's sequence is optimal for each flow-shop line. Heuristic algorithms are developed in this paper by combining a "list scheduling" method and a "local search with global evaluation" method. Numerical experiments show that the proposed heuristics can efficiently give optimal or near-optimal schedules with high accuracy. with high accuracy.

• 산업경영시스템학회지
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• 제29권4호
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• pp.107-112
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• 2006

This study presents the new dispatching rules for improving performance measures of job shop scheduling related to completion time and due dates. The proposed dispatching rule considers information, which includes the comparison value of job workload, work remaining, operation time, and operation due dates. Through computer experiments, the performance of the new dispatching rules is compared and analyzed with the existing rules. The results provide a guidance for the researchers to develop new dispatching rules and for practitioners to choose rules of job shop scheduling.

• Journal of Electrical Engineering and information Science
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• 제1권1호
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• pp.118-128
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• 1996

In safety critical hard real-time systems, a timing fault may yield catastrophic results. In order to eliminate the timing faults from the fast responsive real-time control systems, it is necessary to schedule a code based on high precision timing analysis. Further, the schedulability enhancement by having multiple processors is of wide spread interest. However, although an instruction level parallel processing is quite effective to improve the schedulability of such a system, none of the real-time applications employ instruction level parallel scheduling techniques because most of the real-time scheduling models have not been designed for fine-grain execution. In this paper, we present a timing constraint model specifying high precision timing constraints, and a practical approach for constructing static schedules for a VLIW execution model. The new model and analysis can guarantee timing accuracy to within a single machine clock cycle.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.137-139
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• 2012

This paper presents a system architecture and database of construction quality management system which encourages real time information tracking and monitoring. It improves the real time quality record tracking by using QR code technology in the project delivery. The advantages and issues relative to QR code and the database structures of the tracking system are presented. Conventional project scheduling system, operation modeling and analysis system, and quality management system are hybridized using QR code technology. The system improves project quality management by tracking the atomic tasks which consists of a construction process at the lowest level of construction hierarchy. It analyzes the quality records to determine the causes of abnormality and/or nonconformity. Using QR code technology, the construction quality management system may be more effective than the conventional one. It was confirmed that the quality management processes in construction project delivery can be more visible and controllable by integrating QR code technology, project scheduling system, and quality management system.

• 한국정보통신학회논문지
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• 제4권5호
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• pp.919-930
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• 2000

본 논문은 정수계획 문제로 수리모형화 되는 선박운항 일정계획 문제에 대한 컴퓨터 그래픽기반의 상호대화식 모델링 시스템의 개발에 관해서 논한다. 선박운항 일정계획 문제는 "최대의 운임수익을 얻기 위하여 선박과 화물을 적절히 배정하는 문제"로 요약되며 수리모형과 해법에 대한 많은 연구가 있어왔다. 1970년 후반부터 컴퓨터의 발전에 힘입어 수학적 모델링 뿐만 아니라 컴퓨터 그래픽을 활용한 시각적 상호대화식 모델링에 관한 연구가 시도되었고 현재는 MS/OR(management Science / Operational Research) 및 경영정보시스템(Management Information System : MIS)의 중요한 한 분야가 되었다. 시각적 상호대화식 모델링(Visual Interactive Modeling : VIM)이란 자료의 입력과 모델의 생성 및 해의 표현에 이르는 모델링 생명주기 전체에 걸쳐 의사결정자가 직접 개입하여 의사결정자가 원하는 해를 얻는 과정을 말한다. 본 논문에서는 선박운항일정계획 문제에 있어 컴퓨터 그래픽을 이용한 자료의 입력, 모델의 생성 및 검증, 적절한 해법의 선택 그리고 해의 표현 방법을 제안하고 개발된 프로토타입 시스템을 소개한다.시스템을 소개한다.

• 지능정보연구
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• 제11권3호
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• pp.83-101
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• 2005

고객유지는 갈수록 경쟁이 심화되고 있는 생명보험산업에서 핵심이슈 중에 하나이다. 생명보험사들은 고객을 유지하기 위해서 많은 활동들을 한다. 그 가운데 대표적인 것이 바로 지속적으로 고객과 접촉하는 것이다. 본 연구는 접촉스케줄링시스템(CSS: Contact Scheduling System)의 설계에 대한 것으로 해촉된 모집설계사의 고객을 관리해야만 하는 지원설계사의 고객관리를 돕는 것을 목표로 한다 지원설계사는 모집설계사의 고객관리 경험과 지식을 공유할 수 없다. 이런 지원설계사의 고객접촉을 지원하기 위해서, 본 연구에서는 CSS를 설계한다. CSS설계는 두 단계로 이루어지고, CART(Classification And Regression Tree)와 SPM(Sequential Pattern Mining)의 데이터 마이닝 기법을 활용한다. 단계 1에서는 CART 기법을 이용하여 고객을 8개의 고객군으로 분류한다. 단계 2에서는 각 분류고객군에 적합한 접촉내용, 접촉간격 그리고 접촉방법 등의 접촉스케줄링 정보를 생성한다. 접촉내용은 스케줄 접촉내용, 이벤트접촉내용 그리고 비즈니스규칙에 의한 접촉내용의 결합으로 결정되는데 스케줄접촉내용은 SPM 모델의 결과를 통해 생성된다. 또한 본 연구에서 설계한 CSS가 실제상황에서 어떻게 작동하는지를 제시함으로써 CSS가 효율적이고 효과적인 고객접촉에 실용적임을 보인다.

• 제어로봇시스템학회논문지
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• 제7권1호
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• pp.1162-1170
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• 2001

This paper proposes a practical gain-scheduling control law considering robust stability and performance of Linear Parameter Varying(LPV) systems in the presence of nonlinearities and uncertainties. The proposed method introduces LMI-based pole placement synthesis and also associates with a recently developed fuzzy control system based on Takagei-Sugenos fuzzy model. The sufficient conditions for robust controller design of linearized local dynamics and robust stabilization of fuzzy control systems are reduced to a finite set of Linear Matrix inequalities(LMIs) and solved by using co-evolutionary algorithms. The proposed method is applied to the longitudinal acceleration control of high performance aircraft with linear and nonlinear simulations.

• Journal of Electrical Engineering and Technology
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• 제11권2호
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• pp.329-337
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• 2016

With the increasing deployment of distributed generators in the distribution system, a very large search space is required when dynamic programming (DP) is applied for the optimized dispatch schedules of voltage and reactive power controllers such as on-load tap changers, distributed generators, and shunt capacitors. This study proposes a new optimal voltage and reactive power scheduling method based on dynamic programming with a heuristic searching space reduction approach to reduce the computational burden. This algorithm is designed to determine optimum dispatch schedules based on power system day-ahead scheduling, with new control objectives that consider the reduction of active power losses and maintain the receiving power factor. In this work, to reduce the computational burden, an advanced voltage sensitivity index (AVSI) is adopted to reduce the number of load-flow calculations by estimating bus voltages. Moreover, the accumulated switching operation number up to the current stage is applied prior to the load-flow calculation module. The computational burden can be greatly reduced by using dynamic programming. Case studies were conducted using the IEEE 30-bus test systems and the simulation results indicate that the proposed method is more effective in terms of saving electric charges and improving the voltage profile than loss minimization.