• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.652-659
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• 2003

이 논문은 TOC(Theoyv of Constraints) 기반의 DBR(Dyum-Buffey-Rope) 스케줄링 기법의 기본 개념을 소개하고. 이 기법이 저음 개발되어 오늘에 이르기까지 실제 생산기업에 적용되고 이론적으로 발전되어온 역사를 문헌을 중심으로 고찰하는 것이다. DBR 스케줄링 기법의 기본 개념 및 구조를 간단한 사례를 중심으로 설명하였으며. 1998년 처음 개발된 이후 발표된 논문을 중심으로 프로세스 산업적용, 반도체 산업 적용, DBR과 ERP 통합, MPS 문제, 버퍼 크기 문제, 공급망 관리와의 연계, VAT 분석, JIT와의 연계, 서비스 산업에의 적용. 일반 산업응용 사례, DBR 시스템 개발 등으로 나누어 문한 분석을 한 결과를 제시하였다. 마지막으로 향후 DBR 기법의 발전 방향 등에 대하여 논의하였다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.381-385
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• 2003

We consider the bandwidth parking problem arising from telecommunication networks The problem is to determine the set of calls to be routed and an assignment or them to the paths in arc capacitated network. The objective is to maximize profit. We formulate the problem as an integer programming and propose an algorithm to solve it. Column generation technique to solve the linear programming relxation is proposed with two types of columns in addition, to obtain an optimum integer solution, we consider a new branching strategy. Computational experiments show that the algorithm gives option at solutions within reasonably small time limits.

• Proceedings of the CALSEC Conference
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• 2005.03a
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• pp.261-266
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• 2005

Web services provide an effective means to carry out coordinated transactions between multiple, independent business parties. While there are several specific protocols currently being discussed to address the coordination of web services-enabled business transactions, we consider the tentative hold protocol (THP) that allows the placement of tentative holds on business resources prior to actual transactions in order to provide increased flexibility in coordination. In this paper, we present a formal coordination framework for applying THP in conjunction with 2PC to the problem in which service providers independently manage resources and clients seek to acquire the resources from multiple providers as a single atomic transaction. The proposed framework facilitates the performance optimization of THP through effective parameterization with the notion of overhold size and hold duration. The simulation results show that the proposed adaptive approach yields a significant improvement over other non-adaptive policies.

• The Journal of Society for e-Business Studies
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• v.5 no.1
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• pp.159-192
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• 2000

In spite of seemingly conflicting findings, a meta-analysis of studies published between 1971 and 1998 demonstrates an unambiguous relationship between attitude and IS use. The apparent contradictions arise principally because of methodological inconsistencies in the way that attitude was measured (belief or affect) and the timing of the measurement of attitude vis-5-vis the use of the technology. We found that the affective dimension of attitude is more powerful than the cognitive dimension for explaining IS use. However, neither is particularly strong in predicting future use.

• Journal of ILASS-Korea
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• v.15 no.3
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• pp.150-156
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• 2010

Ethanol has properties of a lower setting point, higher oxygen contents, lower cetane numbers, and also higher volatility compared to biodiesel. Thus, biodiesel fuel can be improved in the fluidity of blending fuel and exhaust emissions by blended ethanol fuel. This research aims to understand combustion characteristics of biodiesel-ethanol blending fuel inside a constant volume chamber. High speed camera was applied to visualize the physics of development of combustion processes, and combustion pressure and exhaust emissions were measured at several blending ratios of ethanol and biodiesel fuel. This information may contribute to improve the performance of biodiesel engine and reduce emissions in future.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.664-667
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• 2001

Segregation of binary particle systems in a horizontally gyrated bed has been experimentally studied to recover the heavy metals from municipal waste incineration (MWI) ash. Differences in density and size had less effect on segregation. Effective segregation took place under the centrifugal effect of 1 or less for any particle size ratio. Zn, Cu and Pb were concentrated in the upper side of bed by the horizontal vibration. However, there was less change in concentration for other metals such as Mg, Al and Fe etc. The separation system with the horizontal gyrating separator proved to be an effective method for the pretreatment of recovering Zn, Cu and Pb from incineration residues.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.691-692
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• 2001

Until tile 1980s, the disposal of End of Life Vehicles (ELV) was considered unproblematic in Japan, Korea. and Taiwan. But in recent years, as environmental problems have attracted increasing attention. the processing oi ELV has become one of the most critical environmental issues. Discarded ELV represent a serious source of waste generation and pollution. In this paper, I will analyze the ELV problem from three view points: 1) ELV abandoned in the environment; 2) Significant environmental hazards caused by dismantling operations; and 3) Problems of how to deal with Automobile Shredder Residue (ASR).

• Proceedings of the IEEK Conference
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• 2003.07a
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• pp.446-449
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• 2003

In recent years, the research of an efficient transmission method is going to meet a demand for high speed and large capacity radio communication. These systems make use of ultra-short duration pulses which yield UWB(Ultra Wide Band) signals characterized by low power spectral densities. The wavelet synthesis wave is able to set up the scale freely. So it is possible to use as the transmission wave of UWB by compressing time. In this paper, we present a general analytical expression for the average BER(Bit Error Rate) performance of UWB data transmission using wavelet system as a function of the cross-correlation between the users' signatures in an additive white Gaussian noise(AWGN) channel.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.9
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• pp.47-56
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• 1994

In this paper, we demonstrate how to design a redundant robot which is suitable for the multiple task execution without any constraints on the work space. The implementation is possible by the rigid connection of a cacro-robot and a micro-robot. A 5 d.o.f. articulated robor designed for commercial purpose is utilized as a micro-robot which can perform a general task with the appropriate adjustment of its base location. The base of a micro-robot is located at a suitable position by the macro-robot designed and implemented through this research. A task assigned to this redundant robot is performed mainly by the micro-robot. However, when the micro-robot cannot perform the task by itself or when the micro-robot has difficulties in performing the task, the coordination of the macro-robot is requited. To monitor the task execution efficiency of the micro-robot, we used the 'Manipulability Measure' as a cost function. The coordination between the two robots are verified both by the simulation and the experiment.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.38 no.12
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• pp.58-66
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• 2001

Input queueing is useful for high bandwidth switches and routers because of lower complexity and fewer circuits than output queueing. The input queueing switch, however, suffers HOL-Blocking, which limits the throughput to 58%. To get around this low throughput, many input queueing switches have centralized scheduler, which centralized scheduler restrict the design of the switch architecture. To overcome this problem, we propose a simple scheduler called PRR(Pipelined Round Robin), which is intrinsically distributed and presents to show the effectiveness of the proposed scheduling.