• Title/Summary/Keyword: Fairness and Efficiency

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Game Theory for Transmission Power Control of Cognitive Radio (CR의 송신 전력 제어를 위한 게임 이론 연구)

  • Hwang, In-Kwan;Lee, Ryoung-Kyoung;Cho, Hae-Keun;Lim, Yeon-Jun;Ko, Eun-Kyoung;Song, Myoung-Sun
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.18 no.4 s.119
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    • pp.448-454
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    • 2007
  • In this paper, the game theory based power control for CDMA system is studied, which has attained intensive interest as a core artificial intelligent technology fur cognitive Radio and its efficiency is evaluated using performance metrics such as system throughput and fairness. Utility Function for joint user centric and network centric power control is defined and simulation results show that game theory based power control is far better than closed loop power control. The contribution of this raper is to formalize the game theory based power control toward the cognitive radio that recognizes and adapts to the radio communication environments.

Optimal Power and Spectrum Allocation Scheme in Multicell WRAN (Multicell WRAN에서의 최적 전력 및 주파수 할당 기법)

  • Hwang, In-Kwan;Lim, Yeon-Jun;Cho, Hae-Keun;Song, Myoung-Sun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.6A
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    • pp.666-675
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    • 2008
  • The IEEE 802.22 standard is being developed with the target of improving the efficiency of spectrum utilization and importing the new wireless communication service. The WRAN standard based on Cognitive Radio is being processed for sharing TV bands. In this paper, the efficient spectrum allocation scheme and the optimal power allocation scheme, Partial Constant Power Water Filling (PCPWF), are proposed to maximize the channel capacity and spectrum efficiency and minimize the interference between adjacent cells. And we maximize the system throughput and fairness by using proposed dynamic cell plan that efficiently allocates channel. The results of the simulations are presented to verify the utilization of our proposed scheme.

Joint Subcarrier and Power Allocation for a Downlink OFDMA Relay Network in Multi-Cell Environments (다중 셀 환경에서 하향 링크 OFDMA 중계 네트워크를 위한 부반송파 및 전력 할당 기법)

  • Choi, Dong-Wook;Lee, Jae-Hong
    • Journal of Broadcast Engineering
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    • v.15 no.2
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    • pp.173-181
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    • 2010
  • In this paper, we propose a new resource allocation scheme for an OFDMA relay network with multicells. In the proposed scheme, by sharing the channel state information (CSI) between base stations, resources are allocated to users and relays to maximize the overall sum of the achievable rate under fairness constraints. In order to reduce the computational complexity, a resource allocation scheme is proposed by separating subcarrier allocation and power allocation into two parts. First of all, by considering inter-cell interference (ICI), a subcarrier is allocated to a user-relay pair, and power is allocated relays. Simulation results show that the proposed scheme achieves higher spectral efficiency per subcarrier than the static scheme and reduces the outage probability compared to the static and greedy schemes.

Comparative Analysis of the 2030 GHG Reduction Target for Eleven Major Countries and Its Implications (주요국의 2030 온실가스 감축목표에 대한 비교분석과 시사점)

  • Oh, Jin-Gyu
    • Journal of Climate Change Research
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    • v.9 no.4
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    • pp.357-368
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    • 2018
  • The Paris Agreement, adopted in 2015, requires global mitigation actions by all countries, whether they are developed or developing countries. All member countries prepared and communicated a greenhouse gas reduction target, formally called the Intended Nationally Determined Contribution (INDC). There has been some concern regarding whether the INDCs communicated are sufficient to achieve the emissions reduction needed to hold the increase in global temperature to $2^{\circ}C$ above pre-industrial levels. How to address this emissions gap in an equitable and fair manner remains controversial. Beginning in the year 2023, global stocktaking under the Paris Agreement will be performed by the Conference of the Parties to assess progress towards temperature goals. The present study, based on various composite indicators reflecting equity, fairness, ability and efficiency, analyzed the GHG reduction targets of eleven major countries and the ambitiousness of these targets. Employing share indicators and comparative ratio indicators (resulting in eight composite indicators), this study showed that when share indicators are applied, Korea's appropriate reduction requirement rate is relatively low at 1~2%. However, when comparative ratio indicators are applied, Korea's appropriate reduction requirement rate increases dramatically to 6~11%. In a similar vein, when share indicators are applied, Korea's 2030 target is very ambitious compared to other countries, while the opposite is seen with comparative ratio indicators. This strongly suggests that Korea needs to apply more share indicators than comparative ratio indicators when discussing the equitable and ambitious role of Korea in the climate debate.

A Feasibility Study on Construction of the Youth Complex Center (청소년수련과 건설사업 타당성분석)

  • No, Byeong-Ok;Song, Jin-U;Choe, Sang-Hyeon;Lee, Sang-Beom
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2003.11a
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    • pp.125-128
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    • 2003
  • This study aims to feasibility study of the Youth Center. Welfare of adolescents is appeared to a matter of concern and interest as social problems of various kinds related adolescents including the fire at a beer bar in Inchon occur recently. In view of government, in addition to fairness of facility location, location of such facilities arc to be determined the respect to cost of locating facilities and developmental direction in the future. A feasibility study is and effective tool in determining the decision of investment or not and the level of investment priority on projects requiring a sizeable investment and the feasibility of a project. The first, it is to select reasonable location. It was selected three and two by consideration of facilities distribution and connection with others. Five proposal selected was estimated by five element of approach, demand, symbol, reality, environment. In result proposal I was chosen. The next, it is to estimate scales. It was estimated by analysis of catchment area, similar facilities, programs, in result 7,260㎡ come into analysis to the best gross area. The finally, it is to study on economical efficiency. Income Statement estimated was came out ₩1,7billion. in addition, it offer various benefit by public facilities.

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A Feasibility Study on Construction of the Youth Complex Center (청소년수련관 건설사업 타당성분석)

  • 노병옥;송진우;최상현;이상범
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2003.05a
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    • pp.125-128
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    • 2003
  • This study aims to feasibility study of the Youth Center. Welfare of adolescents is appeared to a matter of concern and interest as social problems of various kinds related adolescents including the fire at a beer bar in Inchon occur recently. In view of government, in addition to fairness of facility location, location of such facilities are to be determined the respect to cost of locating facilities and developmental direction in the future. A feasibility study is an effective tool in determining the decision of investment or not and the level of investment priority on projects requiring a sizeable investment and the feasibility of a project. The first, it is to select reasonable location. It was selected three and two by consideration of facilities distribution and connection with others. Five proposal selected was estimated by five element of approach, demand, symbol, reality, environment. In result proposal I was chosen. The next, it is to estimate scales. It was estimated by analysis of catchment area, similar facilities, programs, in result 7,260$m^2$ cone into analysis to the best gross area The finally, it is to study on economical efficiency. Income Statement estimated was came out \1.7billion. in addition, it offer various benefit by public facilities.

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A Study of Cell delay for ABR service in ATM network (ATM 네트워크에서 ABR 서비스의 셀 지연 방식에 관한 연구)

  • 이상훈;조미령;김봉수
    • Journal of the Korea Computer Industry Society
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    • v.2 no.9
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    • pp.1163-1174
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    • 2001
  • A general goal of the ATM(Asynchronous Transfer Mode) network is to support connections across various networks. ABR service using EPRCA(Enhanced Proportional Rate Control Algorithm) switch controls traffics in ATM network. EPRCA switch, traffic control method uses variation of the ACR(Allowed Cell Rate) to enhance the utilization of the link bandwidth. However, in ABR(Available Bit Rate) service, different treatments are offered according to different RTTs(Round Trip Times) of connections. To improve the above unfairness, this paper presents ABR DELAY mechanism, in which three reference parameters for cell delay are defined, and reflect on the messages of RM(Resource Management) cells. To evaluate our mechanism, we compare the fairness among TCP connections between ABR DELAY mechanism and ABR RRM mechanism. And also we execute simulations on a simple ATM network model where six TCP connections and a background traffic with different RTTs share the bandwidth of a bottleneck link. The simulation results, based on TCP goodput and efficiency, clearly show that ABR DELAY mechanism improves the fairness among TCP connections.

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A Collision Compensation Method for CSMA/CR Protocol in Wireless LAN (포화상태인 무선랜 네트워크에서 Carrier Sensing Multiple Access with Collision Resolution (CSMA/CR) 프로토콜의 실용화를 위한 충돌 보상 방법)

  • Kim, Ji-in;Park, Byung-hyun;Kwon, YongHo;Rhee, Byung Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.1033-1036
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    • 2013
  • A study about collision resolution is needed because huge file, video and multimedia information are transmitted to wireless LAN. CSMA/CR protocol guarantees fairness, but doesn't consider QoS. To practicalize CSMA/CR protocol in saturation fully-connected single hop network environments, this paper proposes method of collision compensation. previous CSMA/CR protocol chooses CR Slot only considering fairness, but this paper chooses front CR Slot for compensation of collision to station experiencing collisions. The station transmits jam signal and has channel priority of transmission. So transmitting efficiency and successful transmission probability rise. This proposed simple method can offer benefit to station experiencing collisions without additional hardware cost.

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양심의 자유와 대체복무제도에 관한 연구

  • Song, Ha-Yeong
    • Journal of the Korea society of information convergence
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    • v.7 no.1
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    • pp.1-16
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    • 2014
  • In this study, in light of the reality that the need for systematic development of military service resource management and alternative service discipline / switching service discipline has been discussed for illegal liquidation of military service obligations (Tekketsu) in connection with the military service system, and pluralistic it is assumed judgment if centralized military manpower administration (MMA) the recruitment structure that is, military service resource management that to effectively manage. Military service resources decision to systematic management of resources military service, military service of centralized resource management that MMA is the center, the efficiency of the plan. It is determined that it can improve the precision, thereby increasing and the resource-specific Service Discipline instruction, fairness to ensure consistency in the resource management of Alternate Service Discipline / Switching Service Discipline among, high quality and accessibility of such people petition I thought there may be a service provider is realized, that centralization of MMA is also realized, trying to allo improved fairness associated with the performance of military service obligation. Therefore, in this study, we are exploring a scheme that is able to achieve the unification of the human resource management of military service entity to perform the duty of national defense.

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A Study on an Adaptive AQM Using Queue Length Variation

  • Seol, Jeong-Hwan;Lee, Ki-Young
    • Journal of information and communication convergence engineering
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    • v.6 no.1
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    • pp.19-23
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    • 2008
  • The AQM (Active Queue Management) starts dropping packets earlier to notify traffic sources about the incipient stage of congestion. The AQM improves fairness between response flow (like TCP) and non-response flow (like UDP), and it can provide high throughput and link efficiency. In this paper, we suggest the QVARED (Queue Variation Adaptive RED) algorithm to respond to bursty traffic more actively. It is possible to provide more smoothness of average queue length and the maximum packet drop probability compared to RED and ARED (Adaptive RED). Therefore, it is highly adaptable to new congestion condition. Our simulation results show that the drop rate of QVARED is decreased by 80% and 40% compare to those of RED and ARED, respectively. This results in shorter end-to-end delay by decreasing the number of retransmitted packets. Also, the QVARED reduces a bias effect over 18% than that of drop-tail method; therefore packets are transmitted stably in the bursty traffic condition.