• Title/Summary/Keyword: Outage Capacity

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Estimation of the proper capacity of Dispersed Storage and Generation system for uninterruptable service in one bank outage case in 154/22.9KV S/S (154/22.9 KV S/S의 1 BANK 사고시 무정전 전력공급을 위한 분산형 전원의 적정용량 산정 검토)

  • Kim, Jae-Eon;Rho, Dae-Suk;Kim, Ho-Yong
    • Proceedings of the KIEE Conference
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    • 1989.11a
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    • pp.216-219
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    • 1989
  • Over the last decade or so, there has been an increase in activity devoted to the development of renewable resources for generating electric energy. Many of these generators are small and can only be economically connected to the distribution system or to ths subtransmission system. Those which involve storage, a secondary source of energy, can provide a means to achieve more efficient use of existing generating plant. Such systems are known collectively as Dispersed Storage and Generation devices, or DSGs. So, in this paper, for uninterruptable service in one bank outage in 154/22.9KV substation, the proper capacity of DSGs is examined through the configuration and the reliability.

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Increasing Throughput using Bandwidth and Region Division with Frequency Overlay over Multicell Environments (다중 셀 환경에서 주파수 오버레이를 이용한 대역 및 영역 분할 기법에서의 데이터 전송률 향상)

  • Oh, Tae-Geun;Son, Hyuk-Min;Lee, Sang-Hoon
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.245-246
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    • 2008
  • A cell planning and resource allocation scheme called the proposed is presented for improving channel capacity and for maintaining a proper QoS (Quality of Service) over the downlink OFDMA (Orthogonal Frequency Division Multiple Access) system. Through an optimal combination of sectorization and frequency overlay, the proposed scheme accomplishes an improvement in both channel capacity and outage probability. In the simulation, the proposed scheme outperforms 3-sectorization in terms of throughput and outage probability.

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Dynamic Subchannel Grouping Algorithm using Local Gateways for Enterprise Small-cell Networks

  • Kim, Se-Jin
    • Journal of Internet Computing and Services
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    • v.18 no.6
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    • pp.7-13
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    • 2017
  • In this paper, we propose a novel dynamic subchannel grouping (DSG) algorithm to maximize the system capacity considering intended proper outage probability for the downlink of enterprise small-cell networks (ESNs). In the proposed DSG scheme, a local gateway (LGW) which is installed in a building dynamically divides the frequency bandwidth into different numbers of subchannel groups (SGs) based on the numbers of small-cell access points (SAPs) and small-cell user equipments (SUEs) per floor. Then, the LGW assigns the SGs to SAPs and the SAPs allocate them to their serving SUEs. Through simulation results, we show that the proposed DSG scheme is appropriate for the ESNs compared to the conventional small-cell networks in which all SAPs use the number of fixed SGs in terms of the system capacity and outage probability.

Performance Analysis of Hybrid Decode-Amplify-Forward Incremental Relaying Cooperative Diversity Protocol Using SNR-Based Relay Selection

  • Tran, Trung Duy;Kong, Hyung-Yun
    • Journal of Communications and Networks
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    • v.14 no.6
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    • pp.703-709
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    • 2012
  • In this paper, we propose a hybrid decode-amplify-forward incremental cooperative diversity protocol using SNR-based relay selection. In the proposed protocol, whenever destination unsuccessfully receives the source's signal, one of relays that exploit hybrid decode-amplify-forward technique is chosen to retransmit the signal. We derive approximate closed-form expressions of outage probability and average channel capacity. Monte-Carlo simulations are presented to verify the theoretical results and compare the performance of the proposed protocol with the direct transmission protocol and conventional incremental relaying protocols.

Partial Relay Selection for Decode and Forward over Rayleigh Fading Channels (레일리페이딩 환경에서 복호 후 재전송방식을 위한 부분적 릴레이 선택방식 연구)

  • Bao, Vo Nguyen Quoc;Kong, Hyung-Yun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.7A
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    • pp.523-529
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    • 2009
  • This paper provides closed form expressions for the evaluation of the end-to-end outage probability, symbol error rate, bit error rate and average capacity of the partial-based Decode-and-Forward (DF) relay selection scheme with an arbitrary number of relays. In a comparison with the performance of systems that exploit Amplify-and-Forward (AF), it can be seen that the performance of our proposed protocol converges to that of partial-based AF relay selection in high SNR regime. We also perform Monte-Carlo simulations to validate the analysis.

Performance Analysis of an AF Dual-hop FSO Communication System with RF Backup Link

  • Alhamawi, Khaled A.;Altubaishi, Essam S.
    • Current Optics and Photonics
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    • v.3 no.4
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    • pp.311-319
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    • 2019
  • A hybrid free-space-optical/radio-frequency (FSO/RF) communication system is considered, with the help of amplify-and-forward (AF) relaying. We consider various weather conditions to investigate their effects on the system's performance. We begin by obtaining the cumulative distribution function and probability density function of the end-to-end signal-to-noise ratio for the AF dual-hop FSO communication system with RF backup link. Then, these results are used to derive closed-form expressions for the outage probability, average bit-error rate, and average ergodic capacity. The results show that the considered system efficiently employs the complementary nature of FSO and RF links, resulting in impressive performance improvements compared to non-hybrid systems.

Outage Probability Analysis of Dual-Polarized Antenna System (이중 편파 안테나시스템의 오수신 확률 분석)

  • Wang, Hanho;Noh, Gosan;Bahng, Seungjae;Park, Youn Ok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39A no.12
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    • pp.771-773
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    • 2014
  • Dual-polarization antenna system has been being researched for wireless communications under short range line-of-sight channel environments. In this paper, probability density function of signal-to-interference-ratio(SIR) for the dual-polarization antenna system is derived, and SIR outage is analyzed. It is shown that the upper bound capacity of a dual-polarization antenna system without polarization alignment is 4.5324 bps/hz.

Performance analysis of cellular CDMA networks with power control error in nakagami fading channel (Nakagami 페이딩 채널에서 전력 제어 오차를 고려한 셀룰라 CDMA 네트워크의 성능 분석)

  • 이동도;김동희;박용서;황금찬
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.1
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    • pp.1-11
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    • 1997
  • We examine the DS/SSMA system which is employing coherent BPSK with RAKE receiver. We adop Nakagami m-distribution as a multipath fading model. First, we analyze the performances of the system in the single cell environment and obtain the other-cell interference according to power control error. And considering the other-cell interference into the analysis of single cell system, we examine the cellular CDMA network. The average BER and outage probability are the figures of merit that characterize the system performance. The required BER, 1E-3, and required outage probability are the figures of merit that characterize the system performance. The requeired BER, 1E-3, and required outage probability, 1% for the voice transmission is considered to acquire the capacity of system.

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Improved SIR-based call admission control for DS-CDMA cellular system (DS-CDMA 셀룰라 시스템을 위한 SIR기반의 개선된 호 수락 제어)

  • 김호준;박병훈;이진호;황금찬
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.23 no.4
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    • pp.957-966
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    • 1998
  • In this paper an imrpoved Signal-to-Interference ratio(SIR)-based call admission control(CAC) algorithm for DS-CDMA cellular system is proposed and its performance is analyzed. This algorithm uses Residual-Capacity defined asthe additional number of initial calls that a base station can accept such that system-wide outage probability will guaranteed to remain below a certain level. the residual capcity at each cell is calculated according to the reverse-link SIR measured not only at the home cell but also the adjacent cells. Then the adjacent cell interference-coupling coefficient .betha. is used. In this work we propose an improved algorithm that .betha. varies according to the traffic load of the home cell. The influence of traffic condition on system performance, namely blocking probability and outage probability, is then examined via simulation. The performance of the improved algorithm is evaluated both under homogeneous and hot spot traffic loads. The results show that the improved algorithm outperforms conventional algorithms under all load values. Under over-load situation, especially, the improved algorithm gives almost constant outage performance the QoS(quality of service) can be guranted.

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A Study on Construction of the CMELDC at Load Points (각 부하지점별 유효부하지속곡선 작성법에 관한 연구)

  • Kim, Hong-Sik;Mun, Seung-Pil;Choe, Jae-Seok
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.49 no.4
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    • pp.195-198
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    • 2000
  • This paper illustrates a new method for constructing composite power system effective load duration curve(CMELDC) at load points. The main concept of proposed method is that the CMELDC can be obtain from convolution integral processing of the outage probabilistic distribution function of not supplied power and the load duration curve given at each load point. The effective load duration curve (ELDC) at HLI plays an important part in probabilistic production simulation, reliability evaluation, outage cost assessment and power supply margins assesment for power system planning and operation. And also, the CMELDC at HLII will extend the application areas of outage cost assessment and reliability evaluation at each load point. The CMELDC at load points using the Monte Carlo method and a DC load flow constrained LP have already been developed by authors. The effective load concept at HLII, however, has not been introduced sufficiently in last paper although the concept is important. In this paper, the main concept of the effective load at HLII which is proposed in this study is defined in details as the summation of the original load and the probabilistic loads caused by the forced outage of generators and transmission lines at this load point. The outage capacity probabilistic distribution function at HLII can be obtained by combining the not supplied powers and the probabilities of the not supplied powers at this load point. It si also expected that the proposed CMELDC can be applied usefully to research areas such as reliability evaluation, probabilistic production cost simulation and analytical outage cost assessment, etc. at HLII in future. The characteristics and effectiveness of this methodology are illustrated by case study of IEEE-RTS.

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