• Journal of the Korea Computer Industry Society
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• v.2 no.9
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• pp.1225-1232
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• 2001

In this paper, we investigate the scheduling algorithm of router system for Internet services on large scale ATM networks based on the quality-of-service(QoS) level of the input source traffics. We suggest an approprite scheduling algorithm in order to satisfy their QoS requirements. For this purpose, we first study the service requirements of the multiplexer in Internet. Second, we suggest functional architecture of the multiplexer for real time services and the scheduling algorithm to satisfy various QoS requirements. Finally, the performance measures of interest, namely steady-state average delay time and fairness of network resources, are discussed by simulation results.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.329-331
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• 2013

IEEE 802.11 has become the main technology in wireless network. However, in terms of fairness, arise in its use in ad hoc networks. Two independent emitters nodes can easily monopolize the medium, preventing other nodes to send packets. This paper proposes the modified (m,k)-firm scheme which is based on T-MAC to improve fairness. Also, the proposed scheme uses different TA period according to the number of collision in the node. The simulation result shows that the proposed scheme helps improve the fairness of the DCF.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04d
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• pp.469-471
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• 2003

TCP는 패킷손실이 발생할 경우에 이를 혼잡에 의한 것이라고 판단하여 혼잡제어를 수행하는 프로토콜이다. 그러나 무선망은 그 특성상 에러가 많기 때문에 기존의 TCP프로토콜을 그대로 적용할 경우 불필요한 혼잡제어를 수행하게 되어 결국 전체 망의 성능을 떨어뜨리게 된다. 본 논문에서는 링크상태에 따라 송신률을 조절하는 TCP-ELSA 메커니즘 이용하여 링크상태 예측 방법을 개선하였다. TCP-ELSA는 무선링크의 링크상태를 예측하여 송신률을 조절하여 대역폭의 효율을 증가시키고 링크의 공평성을 보장하는 메커니즘이다. 본 논문에서 제안하는 개선된 TCP-ELSA는 링크상태 예측방법에 있어서 오류가 발생할 수 있는 경우를 고려함으로써 공평성을 유지하면서도 좀더 정확한 링크상태의 예측이 가능하도록 한다. 그리고 실시간 패킷을 비실시간 패킷과 구분하여 전송하도록 하여 Qos를 제공하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2019.10a
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• pp.113-114
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• 2019

클라우드 환경에서는 가상머신의 고성능 연산을 지원하기 위해 Graphic Processing Unit(GPU)를 사용한다. 가상머신들은 공평성을 위해 독립적인 가상머신 스케줄러를 사용하기 때문에 컴퓨팅 자원의 초과 사용으로 인한 성능 저하가 발생해도 동일한 작업을 수행하는 가상머신들의 성능은 균등하게 측정된다. 하지만 GPU 연산의 경우 다중 작업을 수행할 때 하드웨어 기반 스케줄러를 사용하며 가상머신의 입출력 작업을 위한 하이퍼바이저의 First In First Out(FIFO) 기반 스케줄링 기법으로 인해 가상머신 사이의 공평성을 보장할 수 없다. 본 논문에서는 GPU 메모리를 초과 사용하는 환경에서 가상머신들의 성능을 측정하고 성능 불균형으로 인한 문제를 분석한다.

• Proceedings of the Korean Family Resource Management Association Conference
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• 2000.05a
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• pp.80-94
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• 2000

• The KIPS Transactions:PartC
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• v.10C no.3
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• pp.305-310
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• 2003

The performance of various GFR implementations has been recently studied due to the interest to provide bandwidth guarantees with a simpler implementation than ABR in ATM networks. One of the important factors is buffer management for guaranteeing QoS in GFR service. An efficient buffer management algorithm is necessary to guarantee MCR for untagged cell in ATM switch. In this paper, we propose and evaluate a buffer management scheme to provide the GFR service guarantees. The proposed scheme can control the cell discarding for fairness in each VC, and compared with Double-EPD and DFBA. Our results show that the proposed buffer management with per-VC queuing achieves significant enhancement on goodputs and fairness index than those of existing methods.

• Journal of Internet Computing and Services
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• v.6 no.3
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• pp.121-128
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• 2005

Recently, as the research of effective resource management for supporting of various next generation internet service, the admission control mechanisms using the dynamic provisioning methods in differentiated service networks are studied. However, even though admission control mechanism is applied to the network, there exits the unfairness of call blocking probability among the different bandwidth requested services. In this paper, we propose the new admission control policy heuristic algorithm that provides fairness of call blocking probability between the large bandwidth requested service and the small bandwidth requested service. The simulation results show that the proposed algorithm provides not only blocking probability fairness but also high bandwidth utilization.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.1
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• pp.37-44
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• 2016

It is important that using of efficient radio resource because of deficiency spectrum problem, so that related to this problem many researches are have proceeded. To solve this problem, Cognitive Radio(CR) was suggested. The channels are allocated to the secondary users when the primary users don't use the channels, and unfairness of secondary users can be serious problem and channel quality of multichannel can be different due to the different traffic pattern of primary users. In this paper, we propose MAC prtocol both of the user's fairness and channel quality in CR networks. Simulation results show the comparison with CR MAC protocols.

• 주택과사람들
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• s.220
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• pp.39-40
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• 2008

주택 관련 조세 제도를 조세 원칙에 부합되도록 재정비해야 한다는 목소리가 높아지고 있다. 주택 가격 안정 대책 차원에서 단기적으로 다룰 문제가 아니라는 이야기다. 효율성.공평성 등 조세 원칙에 부합되는 합리적인 주택 관련 조세 제도는 무엇인지 해외 사례와의 비교를 통해 알아보자. 자료는 김경환-말페지-김정호의<재산권, 규제, 주택시장(자유기업원, 2008.8.)>을 토대로 했다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.2
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• pp.130-139
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• 2013

In recent, the communication networks of wind power farm are becoming crucial technologies for monitoring and controlling the large-scale offshore wind power farm. In this paper, EPON based communication network architectures are proposed in order to combat the problems of conventional Ethernet based communication network such as delay, data processing overhead and the fairness of data transmission among turbines in offshore wind power farm. The proposed architecture constructs the point to multi-point network by using OLT and ONUs installed in central control center and wind turbines respectively. The EPON based communication network architecture has low cost, high reliability, and fair transmission capability. To evaluate the performance of proposed architectures, the wind power farm based on IEC 61850 is modelled by using OPNET The simulation results are analyzed and compared with conventional Ethernet based communication network in terms of the overhead, delay and fairness of data transmission.