• Title/Summary/Keyword: signal adaptation

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A Study on ECLMS Algorithm with Robustness for Echo Cancellation in Double-Talk Environment (동시통화 환경에서 강인한 반향제거 성능을 가진 ECLMS 알고리즘에 관한 연구)

  • Oh, Hak-Joon;Lee, Seung-Whan;Lee, Hae-Soo;Koo, Choon-Keun;Jung, Chan-Soo
    • Proceedings of the KIEE Conference
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    • 2001.11c
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    • pp.142-145
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    • 2001
  • In the double-talk situation where both the near-end and far-end signal present, the performance of echo cancellation using the NLMS algorithm is degraded easily since it freezes the adaptation in this situation. To solve this problem, which utilize the correlation function values of input signal instead of the input signal itself, have been proposed. Because this algorithm could be used to adapt the filter's parameters continuously even in the double-talk situation, give good convergence property compared with the NLMS. In this paper, we compare and analyze its performance. The computer simulation was performed and the results showed as that ECLMS algorithms were robust and kept the desirable performance even in the double-talk situation.

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Software Development for PC-PC Remote Measurement of Automobile's Fault Detection using the Bluetooth (브루투스를 이용한 자동차 고장 진단신호의 PC-PC 원격계측 소프트웨어 개발)

  • 윤여흥;정진호;서진원;이영춘;권대규
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.257-260
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    • 1997
  • Bluetooth is the most promising network paradigm which ca open the new area in the information technology. Especially, bluetooth can link all the electrical products and PCs(Personal Computer) to cellular phone or PDA. In this paper, the data from ECU which are gathered by scanner are communicated between tow PCs using the bluethooth modules. The acquired data are ECU's self diagnosis signal and sensor output signal. Self diagnosis signals are very important to check the ECU's state and sensor output signals. Using these data, the possibility of wireless communication with ECU is developed and verified. Protocol stack of bluetooth is L2CAP through HCI and wireless communication software of ECU's signal is developed using VC++ in Windows 98 environment.

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A Study on Development of App-Based Electric Fire Prediction System (앱기반 전기화재 예측시스템 개발에 관한 연구)

  • Choi, Young-Kwan;Kim, Eung-Kwon
    • Journal of Internet Computing and Services
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    • v.14 no.4
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    • pp.85-90
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    • 2013
  • Currently, the electric fire prediction system uses PIC(Peripheral Interface Controller) for controller microprocessor. PIC has a slower computing speed than DSP does, so its real-time computing ability is inadequate. So with the basic characteristics waveform during arc generation as the standard reference, the comparison to this reference is used to predict and alarm electric fire from arc. While such alarm can be detected and taken care of from a remote central server, that prediction error rate is high and remote control in mobile environment is not available. In this article, the arc detection of time domain and frequency domain and wavelet-based adaptation algorithm executing the adaptation algorithm in conversion domain were applied to develop an electric fire prediction system loaded with new real-time arc detection algorithm using DSP. Also, remote control was made available through iPhone environment-based app development which enabled remote monitoring for arc's electric signal and power quality, and its utility was verified.

Design of an Adaptive Fuzzy Controller using Genetic Algorithm (유전알고리즘을 이용한 적응 퍼지 제어기의 설계)

  • Huh, Sung-Hoe;Seo, Ho-Joon;Park, Jang-Hyun;Yun, Pil-Sang;Park, Gwi-Tae
    • Proceedings of the KIEE Conference
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    • 1999.11c
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    • pp.530-532
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    • 1999
  • In adaptive fuzzy control, system designer develops an adaptive law for the output of the unknown plant to track a given signal. The adaptation gains of the adaptive law are critical elements in the overall system, however, they were used to be selected by the designer's experience or intuition. In this paper, genetic algorithm is used to search an optimal adaptation gain and simulation results will be presented to show the improved tracking responses.

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Molecular Mechanism of Plant Adaption to High Salinity (식물의 고염 스트레스에 대한 반응 및 적응기작)

  • Yun Dae-Jin
    • Journal of Plant Biotechnology
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    • v.32 no.1
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    • pp.1-14
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    • 2005
  • Plant responses to salinity stress is critical in determining the growth and development. Therefore, adaptability of plant to salinity stress is directly related with agriculture productivity. Salt adaptation is a result of the integrated functioning of numerous determinants that are regulated coordinately through an appropriate responsive signal transduction cascade. The cascade perceives the saline environment and exerts control over the essential mechanisms that are responsible for ion homeostasis and osmotic adjustment. Although little is known about the component elements of salt stress perception and the signaling cascade(s) in plant, the use of Arabidopsis plant as a molecular genetic tool has been provided important molecular nature of salt tolerance effectors and regulatory pathways. In this review, I summarize recent advances in understanding the molecular mechanisms of salt adaptation.

A Study of Physiology Signal Change by Air Conditioner Temperature Change (에어컨 온도변동에 따른 생리신호 변화에 관한 연구)

  • Kum, Jong-Soo;Kim, Dong-Gyu;Kim, Hyung-Chul
    • Journal of Fisheries and Marine Sciences Education
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    • v.19 no.3
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    • pp.502-509
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    • 2007
  • This study evaluates thermal comfort by air conditioner temperature raising at the point of time that human body begins to adapt. Thermal comfort according to change of time enters by uncomfortable area gradually at general cold room temperature that magnetic pole is in human body. However, can know that keep continuous thermal comfort in case raise temperature in human body adaptation visual point. Experiments were performed in environmental chamber. Subjects were selected 4 men and 4 women whose life cycle were proved that are similar. The subjects stay in the pretesting room during the 30 minutes and enter the testing room under each experiment conditions. During the experiment, brain wave, electrocardiogram, blood pressure and thermal comfort and sensation responses were measured. In this study, physiological and psychological responses correspond under temperature raising at human body adaptation.

Step-Size Control for Width Adaptation in Radial Basis Function Networks for Nonlinear Channel Equalization

  • Kim, Nam-Yong
    • Journal of Communications and Networks
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    • v.12 no.6
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    • pp.600-604
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    • 2010
  • A method of width adaptation in the radial basis function network (RBFN) using stochastic gradient (SG) algorithm is introduced. Using Taylor's expansion of error signal and differentiating the error with respect to the step-size, the optimal time-varying step-size of the width in RBFN is derived. The proposed approach to adjusting widths in RBFN achieves superior learning speed and the steady-state mean square error (MSE) performance in nonlinear channel environment. The proposed method has shown enhanced steady-state MSE performance by more than 3 dB in both nonlinear channel environments. The results confirm that controlling over step-size of the width in RBFN by the proposed algorithm can be an effective approach to enhancement of convergence speed and the steady-state value of MSE.

A Study on the Robust Direct Adaptive Controller Design in the presence of Unmodelled Dynamics and Disturbances (비모형화 특성과 외란을 고려한 강인한 직접 적응제어기 설계에 관한 연구)

  • Park, Kwan-Jong;Kim, Eung-Seok;Kim, Hong-Pil;Yang, Hai-Won
    • Proceedings of the KIEE Conference
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    • 1990.07a
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    • pp.77-80
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    • 1990
  • This paper presents a continuous-time robust direct adaptive algorithm in the presence of bounded disturbances and / or unmodeled dynamics. In the new algorithm, Narendra's adaptation law is adapted. And a term, proportional to the product of tracking error and normalizing signal, is added to the conventional control law. It is shown that the performance of the adaptive schemes is improved if a proportional adaptation tera is added to the control law. The scalar case is only discussed in the stability analysis. Computer simulation is presented to complement the theoretical result.

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Image Restoration Using OS Filters with Adaptive Windows (적응적 창을 갖는 OS 여파기를 이용한 잡음열화화상의 복원)

  • 양경호;이상길;이충웅
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.1
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    • pp.112-119
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    • 1990
  • Two adaptation procedures are proposed for image restoration, in which the window shapes of OS filters are changed according to the order statistics of signal. In the first procedure, the 2-dimensional window is the union of the 1-dimensional subwindows whose sizes are fixed. In the second procedure, the 2-dimensional window is the union of the 1-dimensional subwindows whose sizes are variable. Compared with existing procedures, our adaptation procedures using order statistics are computationally efficient. Simulation results show that the filters with adaptive window shapes have good performance for the preservation of edges and details of image, and the noise suppression.

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Dynamic Retry Adaptation Scheme to Improve Transmission of H.264 HD Video over 802.11 Peer-to-Peer Networks

  • Sinky, Mohammed;Lee, Ben;Lee, Tae-Wook;Kim, Chang-Gone;Shin, Jong-Keun
    • ETRI Journal
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    • v.37 no.6
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    • pp.1096-1107
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    • 2015
  • This paper presents a dynamic retry adaptation scheme for H.264 HD video, called DRAS.264, which dynamically adjusts the retry limits of frames at the medium access control (MAC) layer according to the impact those frames have on the streamed H.264 HD video. DRAS.264 is further improved with a bandwidth estimation technique, better prediction of packet delays, and expanded results covering multi-slice video. Our study is performed using the Open Evaluation Framework for Video Over Networks as a simulation environment for various congestion scenarios. Results show improvements in average peak signal-to-noise ratios of up to 4.45 dB for DRAS.264 in comparison to the default MAC layer operation. Furthermore, the ability of DRAS.264 to prioritize data of H.264 bitstreams reduces error propagation during video playback, leading to noticeable visual improvements.