• 제목/요약/키워드: rate of convergence

검색결과 3,458건 처리시간 0.041초

Stable Tracking Control to a Non-linear Process Via Neural Network Model

  • Zhai, Yujia
    • 한국융합학회논문지
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    • 제5권4호
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    • pp.163-169
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    • 2014
  • A stable neural network control scheme for unknown non-linear systems is developed in this paper. While the control variable is optimised to minimize the performance index, convergence of the index is guaranteed asymptotically stable by a Lyapnov control law. The optimization is achieved using a gradient descent searching algorithm and is consequently slow. A fast convergence algorithm using an adaptive learning rate is employed to speed up the convergence. Application of the stable control to a single input single output (SISO) non-linear system is simulated. The satisfactory control performance is obtained.

THE CONVERGENCE RATES IN THE ASYMMETRIC LAWS OF LARGE NUMBER FOR NEGATIVELY ASSOCIATED RANDOM FIELDS

  • Ko, Mi-Hwa
    • 호남수학학술지
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    • 제34권2호
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    • pp.209-217
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    • 2012
  • Convergence rates in the law of large numbers for i.i.d. random variables have been generalized by Gut[Gut, A., 1978. Marc inkiewicz laws and convergence rates in the law of large numbers for random variables with multidimensional indices, Ann. Probab. 6, 469-482] to random fields with all indices having the same power in the normalization. In this paper we generalize these convergence rates to the identically distributed and negatively associated random fields with different indices having different power in the normalization.

Performance of Bipolar Optical Spectral Encoding CDMA with Modified PN Codes

  • Chang, Sun-Hyok;Kim, Bong-Kyu;Park, Heuk;Lee, Won-Kyoung;Kim, Kwang-Joon
    • ETRI Journal
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    • 제28권4호
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    • pp.513-516
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    • 2006
  • Experimental demonstration of bipolar spectral encoding code-division multiple-access with modified pseudorandom noise codes is presented. Bipolar spectral encoding is achieved with an erbium-doped fiber amplifier amplified spontaneous emission source and arrayed waveguide gratings. The bit-error rate performance of 1.25 Gbps signal transmission over 80 km single mode fiber is measured in a multiple-user environment.

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적응추정자에 대한 파라메터 수렴속도의 해석 (Analysis of the Parameter Convergence Rate for an Adaptive Identifier)

  • Kim, Sung-Duck
    • 대한전기학회논문지
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    • 제38권2호
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    • pp.127-136
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    • 1989
  • This paper describes the parameter convergence properties of an adaptive system to identify a single-input single-output plant model. It is demonstrated that, by using power spectrum analysis, the persistency of excitation (PE) condition in order to guarantee the exponential stability of the adaptive control system can be transformed into the positive definite behavior for the auto-correlation function matrix of adaptive signal. The existence of parameter nominal values can be analyzed by this condition and the convergence rates of parameter are determined by examining the auto-correlation function. We may use the sufficient richness (SR) of input spectrum instead of the PE condition to analyze the parameter boundedness. It can be shown that the eigen values of the auto-correlation function are always related with adaptive gain, input amplitude and positions or numbers of input spectra. In each case, the variation of parameter convergence rate can be also verified.

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옥상녹화에서 혼합식재에 따른 블루페스큐와 지피초화류의 생육 반응 (Effect of Companion Planting on Growth of Festuca glauca 'Elijah Blue' and Flowering Ground-cover Plants on Green Roofs)

  • 윤용한;서수현;이선영;오득균;주진희
    • 한국환경복원기술학회지
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    • 제24권5호
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    • pp.15-23
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    • 2021
  • This study was carried out to suggest an appropriate plant combination by evaluating the growth of flowering ground-cover plants planted with Festuca glauca 'Eljiah Blue' on the roof-top environment. As for the plant materials, Allium senescens and Chrysanthemum coreanum which are shorter than Festuca glauca 'Eljiah Blue' and Sedum takesimense and Agastache rugosa which are taller than Festuca glauca 'Eljiah Blue' were selected. Festuca glauca 'Eljiah Blue' was planted on Conrol, and Festuca glauca 'Eljiah Blue' with Allium senescens (T1), Festuca glauca 'Eljiah Blue' with Sedum takesimense (T2), Festuca glauca 'Eljiah Blue' with Agastache rugosa(T3), and Festuca glauca 'Eljiah Blue' with Chrysanthemum coreanum (T4) were planted in each experimental plot. Plant height and covering rate were measured to evaluate the growth of Festuca glauca 'Eljiah Blue'. Also, relative growth rate (RGR) of plant height, RGR of plant width, and mortality rate of the flowering ground-cover plants were estimated. Plant height and cover rate of Festuca glauca 'Eljiah Blue' was greatest in T3. RGR of plant height was greater in the order of Agastache rugosa, Allium senescens, Chrysanthemum coreanum, and Sedum takesimense. In particular, RGR of plant width was also greatest for Agastache rugosa. Mortality rates of Agastache rugosa and Allium senescens were lowest at 11%. Therefore, based on good growth of Festuca glauca 'Eljiah Blue' planted with Agastache rugosa, these results were suggested as a desirable combination of plant species for rooftop gardening.

SOME WEIGHTED APPROXIMATION PROPERTIES OF NONLINEAR DOUBLE INTEGRAL OPERATORS

  • Uysal, Gumrah;Mishra, Vishnu Narayan;Serenbay, Sevilay Kirci
    • Korean Journal of Mathematics
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    • 제26권3호
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    • pp.483-501
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    • 2018
  • In this paper, we present some recent results on weighted pointwise convergence and the rate of pointwise convergence for the family of nonlinear double singular integral operators in the following form: $$T_{\eta}(f;x,y)={\int}{\int\limits_{{\mathbb{R}^2}}}K_{\eta}(t-x,\;s-y,\;f(t,s))dsdt,\;(x,y){\in}{\mathbb{R}^2},\;{\eta}{\in}{\Lambda}$$, where the function $f:{\mathbb{R}}^2{\rightarrow}{\mathbb{R}}$ is Lebesgue measurable on ${\mathbb{R}}^2$ and ${\Lambda}$ is a non-empty set of indices. Further, we provide an example to support these theoretical results.

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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가변 상태궤환 이득을 이용한 CDMA 셀룰라 시스템의 제한된 분산전력제어 (A Distributed Constrained Power Control with Variable State Feedback Gain in CDMA Cellular Systems)

  • 이무영;오도창;권우현
    • 제어로봇시스템학회논문지
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    • 제9권12호
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    • pp.1065-1070
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    • 2003
  • We present a power control with variable state feedback gain (VFPC) to improve outage convergence rate of distributed constrained power control. The variable state feedback gain includes the information of the desired SIR changes and must be a decreasing sequence for the convergence. The proof of the convergence is given. The proposed algorithm can improve the outage convergence rate and SIR (Signal to Interference Ratio) response at transient as well as at steady state. The simulation results are given to demonstrate the feasibility of the proposed scheme.

Depression in family members of a patient with asthma: The Korean national health and nutrition examination survey 2007-2012

  • Lee, Kyoung Won;Kim, Hyekyeong;Choi, Jung Mi
    • 보건교육건강증진학회지
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    • 제33권2호
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    • pp.47-55
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    • 2016
  • Objectives: We investigated whether the rate of depressive symptom is higher among family members of asthmatic patient compared to people who had no asthmatic family member. Methods: This study used data from the fourth and fifth Korea National Health and Nutrition Examination Survey (2007-2012). In this cross-sectional study, 15,987 men (mean age 46.4) and 20,906 women (mean age 47.4) were included. To compare the rate of depressive symptoms in individuals who had a family member with asthma and those who did not have, we analyzed data using survey logistic regression. Results: Diagnosed depression was reported by 3.0% of the study population, by 4.2% of asthmatic patient's family member, and by 3.0% of individuals who did not have a family member with asthma. Family members of asthmatic patient increased odds of diagnosed depression compared with those who did not had an asthmatic family member (odds ratio = 1.56, p = 0.008). Conclusions: To prevent depression among family members of asthmatic patient, health education for entire family of asthmatic patient need to be considered. Also, government and policy makers should give more attention to caregivers who had a family member with asthma.

향상된 수렴속도를 가지는 부호 부밴드 적응 필터 (A New Sign Subband Adaptive Filter with Improved Convergence Rate)

  • 이은종;정익주
    • 한국음향학회지
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    • 제33권5호
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    • pp.335-340
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    • 2014
  • 본 논문에서는 충격성 잡음(impulsive noise) 환경 하에서 고유치 분포가 큰 입력 신호를 다루기 위해 제안된 부호 부밴드 적응 필터(Sign Subband Adaptive Filter, SSAF)의 성능을 향상시키기 위한 새로운 SSAF를 제안하였다. 기존에 제안된 SSAF는 각각의 부밴드 입력 신호를 모든 부밴드 입력 신호의 $l_2-norm$으로 정규화하기 때문에 밴드의 수를 증가시켜도 수렴속도가 향상되지 않는다. 본 논문에서는 부밴드 입력 신호를 각각의 부밴드 입력 신호의 $l_2-norm$으로 정규화하며 밴드의 수를 증가시킴에 따라 수렴속도가 증가하는 새로운 부호 부밴드 적응필터를 제안하였다. 시스템 식별 환경에서 두 알고리즘의 성능을 비교하는 컴퓨터 모의 실험을 수행하여 제안된 알고리즘의 수렴속도가 더 빠름을 보였다.