• Journal of Advanced Navigation Technology
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• v.16 no.4
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• pp.641-648
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• 2012

The up-streams of the continuous streaming of data packets with lower importance level in the wireless sink node can cause congestion and delay, they affect on energy efficiency, memory size, buffer size, and throughput. This paper proposes a new wireless sink congestion control mechanism based on tournament scheduling. The proposed method consists of two module parts: stream decision module part and service differentiation module part. The final winner in the tournament controls congestion effectively, minimizes packet loss due to congestion, decreases energy consumption, and improves QoS. The simulation result shows that the proposed method is more effective and has better performance compared with those of congestion descriptor-based control method, reliability-based control method, and best-effort transmission control method.

• The Journal of the Korea Contents Association
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• v.11 no.6
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• pp.59-66
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• 2011

Resource constrained project scheduling problem with multiple resource constraints as well as precedence constraints is well-known as one of the NP-hard problem. Since these problems can't be solved by the deterministic method during reasonable time, the heuristics are generally used for getting a sub-optimal during reasonable time. In this paper, we introduce an efficient genetic algorithm for resource constrained project scheduling problem using crossover which is applying schema theory and real world tournament selection strategy. Experimental results showed that the proposed algorithm is superior to conventional algorithm.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.528-532
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• 2005

한국 프로야구 일정계획은 SLSP(Sports League Scheduling Problem)분야의 문제로서 전형적인 조합최적화 문제이다. 본 연구는 한국 프로야구 일정계획 문제의 제약 조건을 분석하고, 다양한 목적함수에 대해 검토하였다. 또한 이를 효과적으로 풀기 위하여 TTSA(Simulated Annealing for the Traveling Tournament)을 사용하였다. TTSA는 TTP(Traveling Tournament Problem) 문제를 풀기 위해 제안된 방법으로 가능해와 비가능해 영역을 동시에 탐색하여 빠른 시간 안에 좋은 해를 구할 수 있다. 실험은 2005년도 한국 프로야구 리그 일정을 바탕으로 하였으며, 그 결과 팀들의 이동 거리의 총합 최소화, 가장 이동거리가 긴 팀의 이동거리 최소화, 팀 간의 이동거리차이 최소화 측면에서 각각 14%, 22%, 21% 더 좋은 일정을 얻을 수 있었다.

• Journal of Korean Institute of Industrial Engineers
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• v.14 no.2
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• pp.53-61
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• 1988

Games such as baseball, soccer are scheduled by a given game type such as tournament, league or their mixed form. The objective of this paper is to find an efficient game-scheduling method with respect to traveling distance, break-time and other conditions. In this paper we first present two models which minimize traveling distance. The first model that a match is played once each other is solved by a heuristic method. In the second model that a match is played more than once, teams are paired by a modified 0 - 1 programming, and the pairs are rearranged in order to generate a number of workable schedules. Then Expert Systems is applied to solve breake-time and other conditions. In order to represent expertise's knowledge effectively, we present a new design of knowledge-base and data-base, inference engine including many rules and meta-rules which controls the global system. In knowledge-base, binary relation among various attributes is used to ease not only knowledge acquisition but also system execution.