• 제목/요약/키워드: update rate

검색결과 285건 처리시간 0.035초

Distributed Constrained Power Control with Fast Outage Convegence in CDMA systems

  • Lee, Moo-Young;Oh, Do-Chang;Kwon, Woo-Hyen
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.2121-2125
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    • 2003
  • This paper proposes a fast distributed constrained power control (FDCPC) with non-stationary relaxation factor to next power update in CDMA cellular power control system. We review unconstrained control algorithms, the distributed power control (DPC), unconstrained second order power control (USOPC) and DPC with stationary relaxation factor (DPCSRF). Under the unconstrained condition, the convergence analysis shows theoretically that the convergence rate of DPC is the fastest one. However, under the constrained control algorithms, DCPC is not the fastest one any more because of transmission power constraint. To improve the convergence speed, the DCPC with non-stationary relaxation factor (FDCPC) are proposed. Under the constrained condition, the convergence rate of FDCPC outperforms that of DCPC and CSOPC.

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역전파 신경회로망의 수렴속도 개선을 위한 학습파라메타 설정에 관한 연구 (On the configuration of learning parameter to enhance convergence speed of back propagation neural network)

  • 홍봉화;이승주;조원경
    • 전자공학회논문지B
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    • 제33B권11호
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    • pp.159-166
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    • 1996
  • In this paper, the method for improving the speed of convergence and learning rate of back propagation algorithms is proposed which update the learning rate parameter and momentum term for each weight by generated error, changely the output layer of neural network generates a high value in the case that output value is far from the desired values, and genrates a low value in the opposite case this method decreases the iteration number and is able to learning effectively. The effectiveness of proposed method is verified through the simulation of X-OR and 3-parity problem.

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Cooperative Beamformer Design for Improving Physical Layer Security in Multi-Hop Decode-and-Forward Relay Networks

  • Lee, Han-Byul;Lee, Jong-Ho;Kim, Seong-Cheol
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권1호
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    • pp.187-199
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    • 2016
  • In this paper, we consider secure communications in multi-hop relaying systems, where multiple decode-and-forward (DF) relays are located at each individual hop and perform cooperative beamforming to improve physical layer security. In order to determine the cooperative relay beamformer at each hop, we propose an iterative beamformer update scheme using semidefinite relaxation and bisection techniques. Numerical results are presented to verify the secrecy rate performance of the proposed scheme.

Wireless ATM 망에서의 위치관리 및 핸드오프 제어에 대한 연구 (A study on Location Management and Handoff control mechanism in Wireless ATM Networks)

  • 성태경;조문성;김동일;조형래
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 1999년도 춘계종합학술대회
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    • pp.295-300
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    • 1999
  • 무선 ATM망에서 현재와 같은 멀티미디어 이동통신 서비스 제공을 위한 단말의 이동성 관리기법들이 많이 연구되고 있다. 본 논문에서는 이들 이동성 관리기법중 위치등록, 갱신, 그리고 핸드오프 제어기법에 대해 특성을 비교한다. 또한, 점차 소규모화되는 현재의 셀룰라 환경에서와 같이 빈번한 핸드오프 발생환경에 대하여 핸드오프 지연 및 통신단절시간과 속도변화에 따른 호 차단율 및 호 절단율을 비교하였다.

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An Effective Maneuver Detection Strategy with Computational Load Saving

  • Ahn, Byeong-Wan;Park, Jae-Weon;Song, Taek-Lyul
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.63.5-63
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    • 2002
  • In this paper, we are concerned with a maneuver detection algorithm which uses the 'lost' measurements down-sampled for computation load saving when a target is in quiescent motion. In general applications of estimation, measurements are available at a relatively high rate, while the estimation processing equipment can only operate at a lower sampling rate. Furthermore, when a target is in nearly quiescent motion, the update of the tracking filter need not to be implemented with maxim urn process power of the filter since the states of the target vary relatively slowly. This does not give serious degradation on the estimation performance. We consider the maneuver detection problem at the case...

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Improvement of trajectory tracking control performance by using ILC

  • Le, Dang-Khanh;Nam, Taek-Kun
    • Journal of Advanced Marine Engineering and Technology
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    • 제38권10호
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    • pp.1281-1286
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    • 2014
  • This paper presents an iterative learning control (ILC) approach for tracking problems with specified data points that are desired points at certain time instants. To design ILC systems for such problems, unlike traditional ILC approaches, an algorithm which updates not only the control signal but also the reference trajectory at each trial will be developed. The relationship between the reference trajectory and ILC control in tracking problems where there are specified data points through which the system should pass is investigated as the rate of convergence. In traditional ILC, the desired data is stored in a tracking profile file. Due to the huge size of the data file containing the target points, it is important to reduce the computational cost. Finally, simulation results of the presented technique are mentioned and compared to other related works to confirm the effectiveness of proposed scheme.

시변채널 모델에서 다중 탭 갱신 알고리즘에 관한 연구 (A Study on the Multi-Tap Update Algorithm in Time Variant Channel Model)

  • 이승대
    • 한국컴퓨터산업학회논문지
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    • 제7권1호
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    • pp.39-46
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    • 2006
  • 고속의 데이터 전송에 대한 채널의 왜곡을 보상하기 위해 다중 경로 다이버시티 수신을 수행하였다. 다이버시티 가지에 보상 알고리즘을 결합한 수신 구조를 갖는 DS/BPSK 시스템을 구성하고 시스템의 성능을 SNR에 따른 평균 비트 에러율 관점에서 평가하였다. 상호부호간 간섭을 극복하기 위해 L 개의 다이버시티 가지에 비선형 탭 지연선 구조를 사용하고 보상 알고리즘에 따라 탭 계수가 시변채널에 적응하도록 하였다. 그 결과 일반적인 보상 알고리즘에 비해 제안한 알고리즘의 평균 비트 에러율이 $10^{-2}$ 정도 개선되었다.

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A novel visual tracking system with adaptive incremental extreme learning machine

  • Wang, Zhihui;Yoon, Sook;Park, Dong Sun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권1호
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    • pp.451-465
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    • 2017
  • This paper presents a novel discriminative visual tracking algorithm with an adaptive incremental extreme learning machine. The parameters for an adaptive incremental extreme learning machine are initialized at the first frame with a target that is manually assigned. At each frame, the training samples are collected and random Haar-like features are extracted. The proposed tracker updates the overall output weights for each frame, and the updated tracker is used to estimate the new location of the target in the next frame. The adaptive learning rate for the update of the overall output weights is estimated by using the confidence of the predicted target location at the current frame. Our experimental results indicate that the proposed tracker can manage various difficulties and can achieve better performance than other state-of-the-art trackers.

계층적 위치 지역을 이용한 동적 위치 관리 기법 (Dynamic Location Management with Hierarchical Location Area)

  • Lee, Chan-Oh;Kim, Myung-Il;Kim, Sung-Jo
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (3)
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    • pp.661-663
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    • 2002
  • This paper introduces a dynamic location management with hierarchical location area, which helps in reducing location update(LU) and paging cost and hence total location management cost. Users are assigned to appropriate location area level utilizing the call-to-mobility ratio(CMR) value. CMR values are calculated each time a user enters a new cell by computing its mobility rate and incoming call rate, which are the two key factors for defining the size of the location area.

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Bayesian Method for Sequential Preventive Maintenance Policy

  • Kim Hee Soo;Kwon Young Sub;Park Dong Ho
    • 한국신뢰성학회:학술대회논문집
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    • 한국신뢰성학회 2005년도 학술발표대회 논문집
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    • pp.131-137
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    • 2005
  • In this paper, we propose a Bayesian approach to determine the adaptive preventive maintenance(PM) policy for a general sequential imperfect PM model proposed by Lin, Zuo and Yam(2000) that PM not only reduces the effective age of the system but also changes the hazard rate function. Assuming that the failure times follow Weibull distribution, we adopt a Bayesian approach to update unknown parameters and determine the Bayesian optimal sequential PM policies. Finally, numerical examples of the optimal adaptive PM policy are presented for illustrative purposes.

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