• 대한임베디드공학회논문지
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• 제5권2호
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• pp.67-76
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• 2010

Although both functional verification and performance evaluation are necessary for the development of effective and reliable communication systems, they have been often performed independently; by functional modeling with formal language tools and by performance modeling with professional network performance evaluation tools, respectively. Separate and repeated modeling of one system, however, would often result in cost increase and inconsistency between the models. This paper proposes an integrated model design approach in order to overcome this problem that evaluates the performance of a communication protocol designed in SDL with SDL-OPNET model conversion. The proposed technique generates OPNET skeleton code from Tau-generated C code of the SDL model by analyzing the relations between SDL and OPNET models. IEEE 802.2 LLC protocol was used as an example of model conversion to show the applicability and effectiveness of the proposed technique.

• 한국경영과학회지
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• 제27권4호
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• pp.87-109
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• 2002

A satisfiability problem in propositional logic is the problem of checking for the existence of a set of truth values of atomic prepositions that renders an input propositional formula true. This paper describes an empirical investigation of a particular integer programming approach, using the set covering model, to solve satisfiability problems. Our satisfiability engine, SETSAT, is a fully integrated, linear programming based, branch and bound method using various symbolic routines for the reduction of the logic formulas. SETSAT has been implemented in the integer programming shell MINTO which, in turn, uses the CPLEX linear programming system. The logic processing routines were written in C and integrated into the MINTO functions. The experiments were conducted on a benchmark set of satisfiability problems that were compiled at the University of Ulm in Germany. The computational results indicate that our approach is competitive with the state of the art.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 B
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• pp.546-549
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• 1995

Recently, electric utility is facing substantially new stream of business environment, such as pressure of business restructuring, competition with private IPPs, diversification of supply-side and demand-side resource options, environmental externalities and uncertainties. Integrated resource planning(IRP) is very useful and powerful approach for solving complex and diversified electricity supply and demand problems. This paper presents a standardized IRP procedure using multi-attribute decision analysis approach. The selection of the most desirable plan is based on multi-attribute trade-off/risk analysis method and score ranking method. As a case study, 50 plans with 12 scenarios are analyzed.

• 대한안전경영과학회지
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• 제12권3호
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• pp.1-11
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• 2010

Establishing a framework, to explain the path to safety accidents considering major safety management factors such as physical conditions including on-site activities and workplace, as well as human factors as to labor, supervisors, or managers, would be effective as the basis to control project's risks by preventing disasters. Therefore, this study aimed to clarify the mechanism in safety management and disaster occurrence. In order to accomplish the purpose, it identified and classified the factors related to accidents, reviewed the causal relationships among them, and suggested the influence diagram. The results of this research are expected to contribute to reinforcing the preventive management, and facilitating the development of integrated site control system based on safety risks.

• 산업경영시스템학회지
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• 제20권43호
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• pp.163-174
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• 1997

Development of control model and system for AMS (Automated Manufacturing Systems) has long been interested by researchers. Presented in the paper is a systematic approach to constructing a Petri-nets(PNs) model of AMS and method for design a graphical model of a AMS by using a new modeling tool which is called PNs. So, the procedure of modeling in the AMS is the same as current practice of AMS design and is based on the IOM (Integrated Object-oriented Modeling) paradigm. An AMS, which consists of various machine groups, can produce machine parts in different physical dimensions and lot size. To model such a system, the method which utilizes Sub-PNs are proposed. This enables the models according to part routings. The machine group which causes bottleneck is obtained and modified to relieve the problem. By iterating these steps which consist of modelling, simulation, and performance evaluation, an AMS can e obtained which satisfies the required manufacturing conditions. Finally, the implementation issues of PN modeling are addressed. The approach is the IOM from PN modeling by Sub-PNs and the other is a development of IOM tool for the performance evaluation of AMS.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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• pp.620-624
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• 2010

The Integrated Flood Management (IFM) concept intends to obtain the maximum of benefits from the use of floodplains and the minimum of losses from flooding which seems to be the ideal outcome of flood management. For this, different strategies are recommended in order to reach this objective. The implementation of this concept leads to a resilience approach for the adaptive management of floods and is currently on its way to be better understood and integrated as part of the water resources management. There exist a fair amount of strategies to adapt to flooding that have been recommended or already implemented either as planned or autonomous ways of adaptation but their effectivity depends on the specific case where they are applied. This is why this paper looks to give a better overview of the different recommended or implemented strategies by analyzing them regarding their inherent advantages and disadvantages.

• 한국정보처리학회논문지
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• 제4권8호
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• pp.2152-2162
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• 1997

본 논문은 파이프라인 방식의 ASIC 데이타 경로를 제어하기 위한 시간 정지형 콘트롤러의 자동합성에 관한 연구이다. 콘트롤 합성은 콘트롤 사양의 자동 생성과 유한상태기의 합성 및 최적화 단계로 구성된다. 이 유한상태기는 수평분할 방식을 응용하여 최적화되며 최소 면적의 콘트롤러가 합성된다. 실험을 통해 제안된 방식으로 생성된 콘트롤러와 기존 방식으로 합성된 유한상태기 콘트롤러를 비교하였는데 콘트롤러의 면적에서 있어서 큰 감소를 보여준다.

• 대한산업공학회지
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• 제18권1호
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• pp.121-139
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• 1992

AGVS(Automated Guided Vehicle Systems) in material handling have been used widely since late 1970s. Implementation of an AGVS generally requires substantial study to optimize the design and performance of guide-paths. Traditional mathematical approaches have been used with limited success to analyze AGVS. These approaches, however, do not provide a practical tool for guide-path designers. This paper presents a new approach based on rules in designing and assessing AGV guide-paths to improve the design of a closed-loop layout. A framework for the integrated approach is proposed, problem solving procedures are explained, and a case study is reported to demonstrate the framework. Deletion of seldom used guide-paths, and addition of bypasses to solve the congestion problem, are conducted interactively and iteratively through simulation experiments. To visualize the results, a graphic control program is developed and integrated with the AutoMod/AutoGram simulation package.

• 한국유기농업학회지
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• 제10권2호
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• pp.1-28
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• 2002

Regarding the dangers to soil, water and air, which come from current agricultural application measures for nitrogen, a sectoral approach for a non-polluting liquid manure utilization cannot be used any longer. Slurry was not any longer considered as a tiresome waste produced of animal husbandry, but as a valuable fertilizer. The goal of the largest possible utilization of slurry on the farm was and still is in the foreground, An Integrated system approach has to be found. leading to a drastic improvement of nutrient utilization and hence to a considerably reduced nutrient use. This can only be expected, if the organic manure can be applicated at times, when losses through leaching and volatilization can be minimized. The necessary investments for such concepts can clearly be reduced through cooperation.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권12호
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• pp.3338-3351
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• 2012

There is an intuitive connection between signcryption and key agreement. Such a connector may lead to a novel way to construct authenticated and efficient group key agreement protocols. In this paper, we present a primary approach for constructing an authenticated group key agreement protocol from signcryption. This approach introduces desired properties to group key agreement. What this means is that the signcryption gives assurance to a sender that the key is available only to the recipient, and assurance to the recipient that the key indeed comes from the sender. Following the generic construction, we instantiate a distributed two-round group key agreement protocol based on signcryption scheme given by Dent [8]. We also show that this concrete protocol is secure in the outsider unforgeability notion and the outsider confidentiality notion assuming hardness of the Gap Diffie-Hellman problem.