• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 춘계 학술논문 발표대회 학계
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• pp.163-166
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• 2009

All sorts of technique for schedule progress management is being developed recently, These can change and develop the abstractive concept model to a detailed model that describes the visual 3D image about a schedule plan. but, this technique is troublesome, because this requires the handwork by means of connection between 3D-CAD and scheduling Program. In this study, the process of real-time schedule progress control system using the integrated database by 3D-CAD object information system and schedule module is presented. This study present the process of a schedule progress management using UML, and the process of real-time schedule progress management using RFID system. Through this study, we want to realize the rapid generation of estimated schedule information and to simulate and analyze actual schedule information by real-time.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1028-1031
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• 1996

Dynamic scheduling is very important in constructing CIM and improving productivity of chemical processing systems. Computation at the scheduling level requires mostly a long time to generate an optimal schedule, so it is difficult to immediately respond to actual process events in real-time. To solve these problems, we developed dynamic scheduling algorithms such as DSMM(Dynamic Shift Modification Method), PUOM(Parallel Unit Operation Method) and UVVM(Unit Validity Verification Method). Their main functions are to minimize the effects of unexpected disturbances such as process time variations and unit failure, to predict a makespan of the updated dynamic schedule and to modify schedule desirably in real-time responding to process time variations. As a result, the algorithms generate a new pertinent schedule in real-time which is close to the original schedule but provides an efficient way of responding to the variation of process environment. Examples in a shampoo production batch process illustrate the efficiency of the algorithms.

• Journal of Information Processing Systems
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• 제5권3호
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• pp.135-144
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• 2009

Most of the tasks in wireless sensor networks (WSN) are requested to run in a real-time way. Neither EDF nor FIFO can ensure real-time scheduling in WSN. A real-time scheduling strategy (RTS) is proposed in this paper. All tasks are divided into two layers and endued diverse priorities. RTS utilizes a preemptive way to ensure hard real-time scheduling. The experimental results indicate that RTS has a good performance both in communication throughput and over-load.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.886-891
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• 2007

최근 공정관리를 위한 각종 기법들이 개발되고 있으며, 실질적인 시공프로세스를 구체적인 3차원 이미지로 형상화하여 보여줌으로써, 공정계획에 대한 추상적인 개념 모델을 구체적인 것으로 변환하여 발전시킬 수 있다. 하지만 이는 3D-CAD와 공정프로그램을 연계하여 사용하는 방식으로 사람이 정보를 옮겨주거나 입력을 해야 하는 번거로움이 수반된다. 본 연구에서는 3D-CAD 객체 정보 시스템 활용 및 공정자동생성 모듈을 활용하여 통합DB 구축을 통한 실시간 철골공사 공정관리 시스템 프로세스를 구축하였다. 본 연구는 IDEF0 모델을 이용하여 철골공정 관리 프로세스를 제시하였으며, RFID 시스템 설계를 통하여 실시간 진도관리 및 분석 프로세스를 제시하였다. 이를 통해 예상공정정보의 신속한 생성과 실시간으로 실제공정정보와의 비교 ${\cdot}$ 분석 및 시뮬레이션을 실현하고자 한다.

• 한국철도학회논문집
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• 제13권1호
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• pp.23-30
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• 2010

4D CAD에 의한 건설공사 공정관리시스템은 가상건설기법의 그래픽에 의한 계획일정위주 공정관리에 중점을 두고 있으므로 실제 현장상황의 판단에 의한 진도관리가 어려운부분이 있다. 본 연구는 4D CAD기반의 공정관리에 현장 웹카메라를 갖춘 Telepresence 기법을 이용한 원격현장 실시간 진도관리 모니터링체계를 연동하는 공정관기시스템 개발을 시도하고 있다. 개발된 시스템은 철도시설공사에 적용하여 활용성을 검증하였으며, 4D CAD에 의한 계획 공정현황과 웹카메라에 의한 실시간 실제현장 영상을 비교하여 시각적 진도관리를 가능하게 할 수 있다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.153-156
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• 2005

Real-time monitoring and controlling manufacturing process is important because of the unexpected events. When unexpected event like mechanical trouble occurs, prior plan becomes unacceptable and a new schedule must be generated though manufacturing schedule is already decided for order. Regenerating the whole schedule, however, spends much time and cost. Thus automated system which monitors and controls manufacturing process is required. In this paper, we present a system which uses radio-frequency identification and computer vision system. The system collect real-time information about manufacturing conditions and generates new schedule quickly with those information.

• Journal of Information Technology Applications and Management
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• 제14권3호
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• pp.227-236
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• 2007

Students in cyber universities can take every course because there are no physical constraints such as class rooms. On the other hand. cyber universities should take a heavy burden to schedule real-time exams in a designated time period. Any two courses a student takes must not be simultaneously allocated to a time slot in such a schedule. It is well known that the complexity of this kind of scheduling problem increases exponentially as the number of courses does. This research provides a heuristic method to make on-line real-time exam timetables with minimal exam time span. It considers the constraint of not allocating courses a student takes to simultaneous exam time and prioritizes courses by the number of students.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.487-487
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• 2000

The scheduling of real-time tasks needs both correctness and timeliness. But it is not easy to schedule real-time tasks having different characteristics in a single system. In this paper we solve the problem through an approach using the performance evaluation of real-time tasks through fuzzy-random variables. Using the performance evaluation through fuzzy-random variable, we can achieve flexible and efficient scheduling for real-time systems.

• 전기학회논문지
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• 제63권12호
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• pp.1627-1636
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• 2014

In real-time electricity price environment, the energy management system can provide the significant advantage to the residential, commercial and industrial customers since it can reduce the electricity charge by controlling the load operation effectively in response to time-varying price. However, the earlier studies for load management mainly focus on the residential and commercial customers except for the industrial customers because most of load operations in industrial sector are intimately related with production schedule. So, it is possible that the inappropriate control of loads in industrial sector causes huge economic loss. In this paper, therefore, we propose load control algorithm for factory energy management system(F-EMS) to achieve not only minimizing the electricity charges but also maintaining production efficiency by considering characteristics of load operation and production schedule. Considering characteristics of load operation and production schedule, the proposed load control algorithm can reflect the various characteristics of specific industrial customer and control their loads within the range that the production efficiency is maintained. Simulation results show that the proposed load control algorithm for F-EMS leads to significant reduction in the electricity charges and peak power in industrial sector.

• Journal of Information Processing Systems
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• 제7권4호
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• pp.613-626
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• 2011

In this paper, we focus on the pinwheel task model with a variable voltage processor with d discrete voltage/speed levels. We propose an intra-task DVS algorithm, which constructs a minimum energy schedule for k tasks in O(d+k log k) time We also give an inter-task DVS algorithm with O(d+n log n) time, where n denotes the number of jobs. Previous approaches solve this problem by generating a canonical schedule beforehand and adjusting the tasks' speed in O(dn log n) or O($n^3$) time. However, the length of a canonical schedule depends on the hyper period of those task periods and is of exponential length in general. In our approach, the tasks with arbitrary periods are first transformed into harmonic periods and then profile their key features. Afterward, an optimal discrete voltage schedule can be computed directly from those features.