• Title/Summary/Keyword: signal adaptation

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Adaptation of the Cloth 3D Models to the Personal Characters for Fashion Coordination (패션코디를 위한 개인 캐릭터에 의복 3D모텔의 정합)

  • 조은규;최우혁;이용원;최창석;김효숙
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2001.06a
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    • pp.193-196
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    • 2001
  • 본 논문에서는 3D 패션 코디를 위해 의복의 3D 모델을 개인 캐릭터에 정합하는 방법을 제안한다. 정합 방법은 의복 모델의 변형, 인체와 의복의 역전 부위 검색, 의복 모델의 수정의 3단계로 나누어진다. 먼저, 인체와 의복이 부위별로 대응을 이루도록 각각에 특징점을 설정하고, 의복의 공극을 고려하여 의복 모델의 높이, 넓이, 두께를 부위별로 변형한다. 의복 3D모델의 정합 후에도, 부위에 따라 의복의 표면 위에 인체가 노출되는 역전현상이 일어난다. 이를 위해, z-버퍼를 개량한 거리-버퍼의 개념을 제안하여 역전을 효과적으로 검색한다(Collision Detection ). 검색된 부위에서 삼각형을 분할하여 의복 모델을 수정한다.

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Position control of Electro hydrostatic actuator (EHA) using a modified back stepping controller (백스테핑제어기를 이용한 전기유압액추에이터의 위치제어)

  • Nam, D.N.C.;Yoon, J.I.;Ahn, K.K.
    • Journal of Drive and Control
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    • v.9 no.3
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    • pp.16-22
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    • 2012
  • Nowadays, electro hydrostatic actuator (EHA) has shown great advantages over the conventional hydraulic actuators with valve control system. This paper presents a position control for an EHA using a modified back stepping controller. The controller is designed by combining a backstepping technique and adaptation laws via special Lyapunov functions. The control signal consists of an adaptive control signal to compensate for the nonlinearities and a simple robust structure to deal with a bounded disturbance. Experiments are carried out to investigate the effectiveness of the proposed controller.

A Study on an Adaptive Control for SCARA Robot Using Digital Signal Processor (TMS320C50) (디지털 신호 처리기 (TNS320C50)를 사용한 스카라 로봇의 적응제어에 관한연구)

  • 배길호
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1996.03a
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    • pp.114-118
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    • 1996
  • This paper proposes a new technique to the design of adaptive control system using DSPs(TMS320C50) for Digital signal processors are used in implementing real time adaptive control algorithms to provide motion for robotic manipulators. In the proposed scheme, adaptation laws are derived from the improved second stability analysis based on the indirect adaptive control theory. The proposed control scheme is simple in structure, fast in computation. an suitable for implementation of real-time control. Moreover, this scheme does not requre an accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the adaptive controller is illustrated by exeperimental reults for a SCARA robot.

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Design of a Real Time Adaptive Controller for Industrial Robot Using Digital Signal Processor (디지털 신호처리기를 사용한 산업용 로버트의 실시간 적응제어기 설계)

    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.5 no.4
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    • pp.26-37
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    • 1996
  • This paper presents a new approach to the design of adaptive control system using DSPs(TMS320C30) for robotic manipulators to achieve trajectory tracking by the joint angles Digital signal processors are used in implementing real time adaptive control algorithms to provide an enhanced motion control for robotic manipulators. In the proposed control scheme adaptation laws are derived from the improved Lyapunov second stability analysis method based on the adaptive model reference control theory. The adaptive controller consists of an adaptive feedforward controller. feedback controller. and PID type time-varying auxiliary control elements. The proposed adaptive control scheme is simple in structure, fast in computation, and suitable for implementation of real-time control. Moreover, this scheme does not require a an accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the adaptive controller is illustrated by simulation and experimental results for a SCARA robot.

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An OTA with Positive Feedback Bias Control for Power Adaptation Proportional to Analog Workloads

  • Kim, Byungsub;Sim, Jae-Yoon;Park, Hong-June
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.15 no.3
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    • pp.326-333
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    • 2015
  • This paper reports an adaptive positive feedback bias control technique for operational transconductance amplifiers to adjust the bias current based on the output current monitored by a current replica circuit. This technique enables operational transconductance amplifiers to quickly adapt their power consumption to various analog workloads when they are configured with negative feedback. To prove the concept, a test voltage follower is fabricated in $0.5-{\mu}m$ CMOS technology. Measurement result shows that the power consumption of the test voltage follower is approximately linearly proportional to the load capacitance, the signal frequency, and the signal amplitude for sinusoidal inputs as well as square pulses.

Design and Implementation of the Quality Performance Improvement for Process System Using Neural Network (가공시스템에서 신경회로망을 이용한 품질의 성능 개선에 관한 설계 및 구현)

  • 문희근;김영탁;김수정;김관형;탁한호;이상배
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2002.12a
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    • pp.179-182
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    • 2002
  • In this paper, this system makes use of the analog sensor and converts the feature of fish analog signal when sensor is operating with CPU(80C196KC). Then, After signal processing, this feature Is classified a special feature and a outline of fish by using the neural network, one of the artificial intelligence scheme. This neural network classifies fish pattern of very simple and short calculation. This has linear activation function and the error backpropagation is used as a learning algorithm. And the neural network is learned in off-line process. Because an adaptation period of neural network is too long time when random initial weights are used, off-line learning Is induced to decrease the Progress time We confirmed this method has better performance than somewhat outdated machines.

Efficient Link Adaptation Scheme using Precoding for LTE-Advanced Uplink MIMO (LTE-Advanced에서 프리코딩에 의한 효율적인 상향링크 적응 방식)

  • Park, Ok-Sun;Ahn, Jae-Min
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.2B
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    • pp.159-167
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    • 2011
  • LTE-Advanced system requires uplink multi-antenna transmission in order to achieve the peak spectral efficiency of 15bps/Hz. In this paper, the uplink MIMO system model for the LTE-Advanced is proposed and an efficient link adaptation shceme using precoding is considered providing error rate reduction and system capacity enhancement. In particular, the proposed scheme determines a transmission rank by selecting the optimal wideband precoding matrix, which is based on the derived signal-to-interference and noise ratio (SINR) for the minimum mean squared error (MMSE) receivers of $2{\times}4$ multiple input multiple output (MIMO). The proposed scheme is verified by simulation with a practical MIMO channel model. The simulation results of average block-error-rate(BLER) reflect that the gain due to the proposed rank adapted transmission over full-rank transmission is evident particularly in the case of lower modulation and coding scheme (MCS) and high mobility, which means the severe channel fading environment.

Transform Domain Adaptive Filtering with a Chirp Discrete Cosine Transform LMS (CDCTLMS를 이용한 변환평면 적응 필터링)

  • Jeon, Chang-Ik;Yeo, Song-Phil;Chun, Kwang-Seok;Lee, Jin;Kim, Sung-Hwan
    • The Journal of the Acoustical Society of Korea
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    • v.19 no.8
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    • pp.54-62
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    • 2000
  • Adaptive filtering method is one of signal processing area which is frequently used in the case of statistical characteristic change in time-varing situation. The performance of adaptive filter is usually evaluated with complexity of its structure, convergence speed and misadjustment. The structure of adaptive filter must be simple and its speed of adaptation must be fast for real-time implementation. In this paper, we propose chirp discrete cosine transform (CDCT), which has the characteristics of CZT (chrip z-transform) and DCT (discrete cosine transform), and then CDCTLMS (chirp discrete cosine transform LMS) using the above mentioned algorithm for the improvement of its speed of adaptation. Using loaming curve, we prove that the proposed method is superior to the conventional US (normalized LMS) algorithm and DCTLMS (discrete cosine transform LMS) algorithm. Also, we show the real application for the ultrasonic signal processing.

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Application of Adaptive Line Enhancer for Detection of Ball Bearing Defects (볼 베어링의 결함검출을 위한 Adaptive Line Enhancer의 적용)

  • Kim Young Tae;Choi Man Yong;Kim Ki Bok;Park Hae Won;Park Jeong Hak;Kim Jong Ock;Lyou Jun
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.14 no.2
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    • pp.96-103
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    • 2005
  • The early detection of the bearing defects in rotating machinery is very important since the critical failure of bearing causes a machinery shutdown. However it is not easy to detect the vibration signal caused by the initial defects of bearing because of the high level of random noise. A signal processing technique, called the adaptive line enhancer(ALE) as one of adaptive filter, is used in this study. This technique is to eliminate random noise with little a prior knowledge of the noise and signal characteristics. Also we propose the optimal methods fir selecting the three main ALE parameters such as correlation length filter order and adaptation constant. Vibration signals f3r three abnormal bearings, including inner and outer raceways and ball defects, were acquired by Anderon(angular derivative of radius on) meter. The experimental results showed that ALE is very useful f3r detecting the bearing defective signals masked by random noise.

Improvement for Hearing Aids System Using Adaptive Beam-forming Algorithm (적응 빔포밍 기법을 적용한 보청기 시스템의 성능 향상에 관한 연구)

  • 이채욱;오신범
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.5C
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    • pp.673-682
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    • 2004
  • The adaptive beam-forming is promising approach for noise reduction in hearing aids. This approach has come in the focus of interest only recently, because of the availability of new and powerful digital signal processors. The adaptation U using usually a Least Mean Squares algorithm, updates the weight vector. In this Paper, we propose a fast wavelet based adaptive algorithm using variable step size algorithm which varies adaptive constant by the change of signal environment. We compared the performance of the proposed algorithm with the known adaptive algorithm using computer simulation of multi channel adaptive bemformer in hearing aids. As the result the proposed algorithm is suitable for adaptive signal processing area using hearing aids and has advantages reducing computational complexity. And we show the beam-forming system using proposed algorithm converges stably in a sudden change of system environment.