• KIISE Transactions on Computing Practices
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• v.23 no.10
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• pp.605-610
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• 2017

In distributed environments, dynamic partitioning is needed to resolve the load on a particular server or the load caused by communication among servers. In heterogeneous environments, existing dynamic partitioning schemes can distribute the same load to a server with a low physical performance, which results in a delayed query response time. In this paper, we propose a dynamic partitioning scheme for large RDF data in heterogeneous environments. The proposed scheme calculates the query loads with its frequency and the number of vertices used in the query for load balancing. In addition, we calculate the server loads by considering the physical performance of the servers to allocate less of a load to the servers with a smaller physical performance in a heterogeneous environment. We perform dynamic partitioning to minimize the number of edge-cuts to reduce the traffic among servers. To show the superiority of the proposed scheme, we compare it with an existing dynamic partitioning scheme through a performance evaluation.

• Proceedings of the IEEK Conference
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• 2003.07d
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• pp.1661-1664
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• 2003

The transcoding is a method which converts a multimedia stream to an adaptive format, such as frame rate and resolution, that can be played in the mobile devices. Due to the heavy consumption of CPU power for transcoding, the server in charge cannot supply all streams requested from clients if it is already occupied by several streams. The load balancing among proxies is a common approach for solving such problem. In addition to collaborative works for load balancing, the mobility must be taken into account in the mobile environments. Thus, the wired-network based algorithm is not suitable for the streams service in the mobile environments. In this paper, we propose an alternative scheme for cooperative proxy architecture that considers the case in which mobile devices are moving over other zones.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.2
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• pp.33-39
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• 2015

Power supplying capacity of the distribution feeder should be maintained within thermal capacity of the wire. This paper presents the minimum spanning tree based load balancing technique to release multiple overloading of distribution feeders. In order to minimize number of involved backup feeders, Dijkstra and Prim algorithm are adopted to construct minimum spanning tree. Simulation testing result based on part of KEPCO's commercial distribution systems shows effectiveness of proposed scheme.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.6
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• pp.683-687
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• 2010

In this paper, we propose an anycast routing scheme for large-scale wireless mesh networks, which requires only one-hop local information with no flooding overhead. We develop an analytical model for anycast mesh networks based on an electrostatic theory. A finite difference method contributes to achieving gateway load balancing with constant control overheads. We verify the performance of the proposed scheme by simulations.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06d
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• pp.273-276
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• 2011

최근 소셜 네트워킹, 멀티미디어 서비스의 사용량이 증가됨에 따라 인터넷의 트래픽은 이전보다 빠르게 증가되고 있다. 이에 링크나 노드의 failure 같은 네트워크 failure 발생은 서비스 이용자들에게 큰 영향을 미치게 된다. 이러한 failure로 부터 빠르게 회복하기 위한 다양한 Fast Reroute scheme들이 제안되었다. 하지만 이러한 Fast Reroute의 Back-path는 특정 링크에게 과도한 트래픽을 유발하게 된다. 본 논문에서는 이러한 점을 해결하기 위한 실제적인 Link Cost를 고려한 Load-Balancing기법을 제안한다. 실험결과 평균 degree가 높을수록 대체가능한 경로들이 증가되기 때문에 FIR에 비해 성능이 향상됨을 확인할 수 있었다.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.5
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• pp.417-424
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• 2022

This study proposes a current-balancing technique for an interleaved buck converter using a variable inductor and a snubber capacitor. The proposed scheme balances the inductor current by using the variable inductor and enables zero voltage switching under all load ranges. With the variable inductor, the ripple of inductor current changes according to load variation. In addition, a 1.6 kW prototype is built to verify the validity of the proposed scheme, and the experimental results are successfully obtained.

• Journal of Internet Computing and Services
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• v.3 no.6
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• pp.53-61
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• 2002

This paper propose an dynamic load balancing algorithm for heterogeneous distributed systems. The algorithm allows this tasks to be relocated. The key of the algorithm is to transfer a suitable amount of processing demand from senders to receivers. This amount is determined dynamically during sender-receiver negotiations. Factors considered when this amount is determined include processing speeds of different nodes, the current load state of both sender and receiver, and the processing demands of tasks eligible for relocation. This paper also propose a load state measurement scheme which is designed particularly for heterogeneous systems. This results of the study show that the proposed algorithm outperforms the existing algorithms and is stable over a range of system attributes.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.11C
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• pp.140-147
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• 2001

In this paper, we propose a scheme of calculating resources\` costs for precomputation in QoS routing schemes. This scheme is effective in respect to the g1oba1 network utilization and the balanced use of network resources. We also propose a QoS routing scheme for transit and intra traffic in a large scale of domain-based network. For a domain in the network, the routing scheme first precomputes multiple paths between all pairs of ingress and egress border routers while considering balancing of the expected load and then selects paths with the probability of path selection. We, therefore, expect that the paths are better than any other paths in respect to reserving the network resources on paths. The routing scheme combines inter and intra domain routings seamlessly and uses the same cost calculation scheme. And for analysis of a load balancing cost calculation proposed a simulation is done.

• The KIPS Transactions:PartC
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• v.11C no.7 s.96
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• pp.889-894
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• 2004

Most ad-hoc routing protocols such as AODV(Ad Hoc On-Demand Distance Vector) and DSR(Dynamic Source Routing) do not try to search for new routes if the network topology does not change. Hence, with low node mobility, traffic may be concentrated on several nodes, which results in long end-to-end delay due to congestion at the nodes. Furthermore, since some specific nodes are continuously used for long duration, their battery power may be rapidly exhausted. Expiration of nodes causes connections traversing the nodes to be disrupted and makes many routing requests be generated at the same time. Therefore, we propose a load balancing approach called Simple Load-balancing Approach (SLA), which resolves the traffic concentration problem by allowing each node to drop RREQ (Route Request Packet) or to give up packet forwarding depending on its own traffic load. Meanwhile, mobile nodes nay deliberately give up forwarding packets to save their own energy. To make nodes volunteer in packet forwarding. we also suggest a payment scheme called Protocol-Independent Fairness Algorithm (PIEA) for packet forwarding. To evaluate the performance of SLA, we compare two cases where AODV employs SLA or not. Simulation results show that SLA can distribute traffic load well and improve performance of entire ad-hoc networks.

• The KIPS Transactions:PartA
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• v.11A no.4
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• pp.257-266
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• 2004

Mobile agents are defined as processes which can be autonomously delegated or transferred among the hosts in a network in order to perform some computations on behalf of the user and co-operate with other agents. Currently, mobile agents are used in various fields, such as electronic commerce, mobile communication, parallel processing, search of information, recovery, and so on. In pure P2P network environment, if mobile agents that require computing resources rashly migrate to another peers without consideration on the peer's capacity of resources, the peer may have a problem that the performance of the peer is degraded due to lack of resources. To solve this problem, we propose resource reservation based load balancing scheme of using RMA(Resource Management Agent) that monitors workload information of the peers and that decides migrating agents and destination peers. In mobile agent migrating procedure, if the resource of specific peer is already reserved, our resource reservation scheme prevents other mobile agents from allocating the resource.