• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2013년도 춘계학술발표대회
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• pp.418-420
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• 2013

Issues on design of routing scheme and routing metric for multicast in multi-channel multi-radio (MCMR) wireless mesh networks (WMNs) are discussed. Emphasis is placed on channel-diversity oriented routing metrics. From case study the conclusion to be drawn is that the key for design of channel-diversity oriented routing metrics is how to construct an optimization function to quantify interdependence between channel assignment and multicast routing throughput.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권4호
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• pp.651-669
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• 2013

In this paper, we study a novel routing algorithm based on load balancing for multi-channel wireless mesh networks. In order to increase the network capacity and reduce the interference of transmission streams and the communication delay, on the basis of weighted cumulative expected transmission time (WCETT) routing metric this paper proposes an improved routing metric based on load balancing and channel interference (LBI_WCETT), which considers the channel interference, channel diversity, link load and the latency brought by channel switching. Meanwhile, in order to utilize the multi-channel strategy efficiently in wireless mesh networks, a new channel allocation algorithm is proposed. This channel allocation algorithm utilizes the conflict graph model and considers the initial link load estimation and the potential interference of the link to assign a channel for each link in the wireless mesh network. It also utilizes the channel utilization percentage of the virtual link in its interference range as the channel selection standard. Simulation results show that the LBI_WCETT routing metric can help increase the network capacity effectively, reduce the average end to end delay, and improve the network performance.

• 대한전자공학회논문지TE
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• 제42권1호
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• pp.1-6
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• 2005

채널 배선은 VLSI 설계 과정중의 하나로, 글로벌 배선을 수행한 후 각 배선 영역에 할당된 네트들을 트랙에 할당하여 구체적인 네트들의 위치를 결정하는 문제이며, 네트들이 할당된 트랙의 수를 최소화하는 문제이다. 본 논문에서는 4-레이어 채널 배선 문제에 대하여 유전자 알고리즘(genetic algorithm; GA)을 이용한 해 공간 탐색(solution space search) 방식을 제안하였으며, 제안한 방식을 기존의 4-레이어 채널 배선 알고리즘과 비교, 분석하였다.

• 전자공학회논문지C
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• 제34C권7호
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• pp.9-17
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• 1997

This paper proposes a routing model based on the HVHD for four-layer routing problems. Differing from the HVHV and HVHH models, the proposed HVHD model permits diagonal routing on the fourth laye rwith a grid of 45.deg., 90.deg. and 135.deg. directions. The developed algorithm which uses a channel-graph including weights routes a layer using diagonal model and the othe rthree layers using HVH model. Applications to several benchmark examples verify that approximately 10~25 percent reduction of channel density can be achieved compared to the conventional four-layer channel routing algorithms.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권5호
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• pp.2362-2378
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• 2017

To mitigate the performance degradation caused by performance anomaly, a number of channel assignment algorithms have been proposed for multi-rate wireless mesh networks. However, network conditions have not been fully considered for routing process in these algorithms. In this paper, a joint scheme called Multi-rate Dijkstra's Shortest path - Rate Separated (MDSRS) is proposed, combining routing metrics and channel assignment algorithm. In MDSRS, the routing metric are determined through the synthesized deliberations of link costs and rate matches; then the rate separated channel assignment is operated based on the determined routing metric. In this way, the competitions between high and low rate links are avoided, and performance anomaly problem is settled, and the network capacity is efficiently improved. Theoretical analysis and NS-3 simulation results indicate that, the proposed MDSRS can significantly improve the network throughput, and decrease the average end-to-end delay as well as packet loss probability. Performance improvements could be achieved even in the heavy load network conditions.

• 융합신호처리학회논문지
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• 제3권3호
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• pp.63-69
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• 2002

디테일드 라우팅은 VLSI 설계 과정중의 하나로, 글로벌 라우팅을 수행한 후 각 라우팅 영역에 할당된 네트들을 트랙에 할당하여 구체적인 네트들의 위치를 결정하는 문제이며, 디테일드 라우팅에서 최적의 해를 얻기 위해 left-edge 알고리즘, dogleg 알고리즘, greedy 채널 라우팅 알고리즘등이 이용된다 본 논문에서는 디테일드 라우팅 문제에 대하여 유전자 알고리즘(genetic algorithm; GA)을 이용한 해 공간 탐색(solution space search) 방식을 제안하였으며, 제안한 방식을 greedy 채널 라우팅 알고리즘과 비교, 분석하였다.

• 대한전자공학회논문지
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• 제25권5호
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• pp.572-579
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• 1988

In this paper, a system of automatic placement and routing for gate array layout design is proposed. In the placement stage, the circuit is partitioned and using the concept of min-cut slicing, and each partitioned module is placed, so that the routing density over the entire chip be uniformized and the total wiring length be minimized. In the global routing stage, the concept of the probabilistic routing density is introduced to unify the wiring congestions in each channel. In the detailed routing stage, the multi-terminal nets are partitioned into the two-terminal nets. The ordered channel graph is proposed which implies the vertical and the horizontal constranint graphs simultaneously. And using the ordered channel graph, the proposed routing algorithm assigns the signal nets to the tracks. Also the proposed placement and routing algorithms are implimented on IBM/PC-AT to construct PC-level gate array layout system.

• 한국수자원학회논문집
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• 제43권12호
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• pp.1051-1061
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• 2010

본 연구에서는 Muskingum 하도추적모형을 수문학적으로 재해석하여 지체효과만을 고려하는 선형하천모형과 저류효과만을 고려하는 선형저수지모형의 선형결합으로 나타내었다. 유도된 모형은 일종의 순간단위도의 형태가 되며, 그 매개 변수는 Muskingum 모형의 매개변수와 동일하다. 즉, 추적시간간격 ${\Delta}t$ 또는지체시간 $T_c$ 후에 최초의 유출이 발생하게 되고, 총 유입량 중 x 만큼은 선형하천모형에 의해 저류효과 없이 빠져나가고 나머지(1-x) 만큼은 선형저수지모형에 의해 저류상수 $K_c$로 대변되는 저류효과를 나타내며 빠져나가는 형태이다. Muskingum 하도추적 모형과 그에 대응하는 순간단위도를 가상하도에 적용해 본 결과, 두 모형이 근본적으로 하도추적결과가 동일함을 확인하였다. 이러한 결과는 대청댐 방류량에 대한 금남 및 공주지점까지의 하도추적결과에서도 확인할 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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• pp.591-593
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• 1998

As evolution of the process technology, we proposed the Over-The-Cell channel routing algorithm for the advanced three-layer process. The proposed algorithm simplifies the channel routing problem, and then makes use of Simulated Annealing Technique to converge at global optimal solution. Also, we proposed a new method to remove the cyclic vertical constraints which are known to be the hardest element in the channel routing problem and a way to detect the local minimal solution and escape from it successfully.

• 상하수도학회지
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• 제12권2호
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• pp.127-139
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• 1998

The objectives of this study is at the development of the channel routing model which can be used for flood prediction. Among the routing models, the hydraulic technique of the implicit scheme in the dynamic equation is selected to route the unsteady varied flow in the open channel. The channel routing model is catchment runoff which computed by the conceptual and transfer function model. The conceptual and transfer function model can simulate the catchment runoff accurately. As a result of investigating the channel routing model, the optimal weighting factor ${\theta}$ which fixes two points between time line is chosen, and also, the optimal error tolerance which satisfies computing time and converge of solution is determined in this study.