• Title/Summary/Keyword: Discrete signal

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New Mexican Hat, a Discrete Reconstruction Theorem of $L^1$-Wavelets and Their Applications (새로운 Mexican Hat, $L^1$-웨이브릿의 이산복원정리와 그 응용)

  • 안주원;허영대;권기룡;류권열;문광석
    • Journal of Korea Multimedia Society
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    • v.3 no.5
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    • pp.461-469
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    • 2000
  • A wavelet analysis in a field of analytics is to create a reconstruction theorem of Plancherel form. And a series of wavelet is to create a discrete is to create a discrete reconstruction theorem for a frame theory and a multiresolution analysis theory. As a generation of reconstruction theorem, a wavelet correspond to it is generated. That is to be like a basic wavelet which is satisfied an admissibility condition in CWT and a Daubechies wavelet using MRA in wavelet series and a Meyer wavelet using a frame theory. In this paper, we discover a discrete reconstruction theorem which is superior to a conventional discrete reconstruction theorem by extending admissibility condition used in CWT and develop a New $L^1$-wavelet group. A new $L^1$-wavelet is applied to a signal reconstruction and a signal analysis in time-frequency region.

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A Study of the Compression for the Power Quality Disturbance Signal by using the Phase Estimation of Stationary Signal (정상신호의 위상 추정을 이용한 전력 품질 왜곡 신호의 압축에 관한 연구)

  • Chung, Young-Sik;Park, Chan-Woong
    • Proceedings of the KIEE Conference
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    • 2005.07a
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    • pp.341-343
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    • 2005
  • This paper introduces a compression algorithm for power quality disturbance signal via the discrete wavelet transform, DWT. Algorithm to estimate a time delay from the power quality disturbance signal is proposed. Pseudo-stationary signal is constructed from the estimated time delay. A difference signal or nonstationary signal is obtained by removing a pseudo-stationary signal from a disturbance signal. DWT is applied to a difference signal. The threshold is applied to reduce a number of coefficients. Simulation results show the resonable compression ratio while keep low signal distortion.

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Advanced Sound Source Localization Study Using De-noising Filter based on the Discrete Wavelet Transform(DWT) (이산 웨이블릿 변환 기반 디-노이징 필터를 이용한 향상된 음원 위치 추정 연구)

  • Hwang, Bo-Yeon;Jung, Jae-Hoon;Lee, Jang-Myung
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.12
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    • pp.1185-1192
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    • 2015
  • In this paper, a study of advanced sound source localization is conducted by eliminating the noise of the sound source using the discrete wavelet transform. And experiments are conducted to evaluate the performance of the proposed system that the mobile robot follows sound source stably. In addition, we compare the position estimation performance by applying a discrete wavelet transform to improve the reliability of the sound signal. The experimental results reveal that the de-nosing filter which removes the noise component in sound source can make the performance of position estimation more precisely and help the mobile robot distinguish the objective sound source clearly.

Sensitivity Analysis of Power System Oscillation Modes Induced by Periodic Switching Operations of SVC by the RCF Method (RCF 기법을 이용한 SVC의 주기적 스위칭 동작에 의한 전력계통 진동모드 감도해석)

  • Kim, Deok-Young
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.3
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    • pp.363-368
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    • 2008
  • In this paper, the Resistive Companion Form(RCF) analysis method is applied to analyze small signal stability of power systems including thyristor controlled FACTS equipments such as SVC. The eigenvalue sensitivity analysis algorithm in discrete systems based on the RCF analysis method is presented and applied to the power system including SVC. As a result of simulation, the RCF analysis method is proved very effective to precisely calculate the variations of eigenvalues or newly generated unstable oscillation modes after periodic switching operations of SVC. Also the eigenvalue sensitivity analysis method based on the RCF analysis method enabled to precisely calculate eigenvalue sensitivity coefficients of controller parameters about the dominant oscillation mode after periodic switching operations in discrete systems. These simulation results are different from those of the conventional continuous system analysis method such as the state space equation and proved that the RCF analysis method is very effective to analyze the discrete power systems including periodically operated switching equipments such as SVC.

Decoupling of Free Decay Roll Data by Discrete Wavelet Transform (이산 웨이블렛 변환을 이용한 자유감쇠 횡요 데이타의 분리)

  • Kwon, Sun-Hong;Lee, Hee-Sung;Lee, Hyoung-Suk;Ha, Mun-Keun
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2001.10a
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    • pp.169-173
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    • 2001
  • This study presents the results of decoupling of free decay roll test data by discrete wavelet transform. Free roll decay test was performed to decide the coefficients of damping terms in equation of motion. During the experiment, a slight yaw motion was found while the model was in the free roll decay motion. Discrete wavelet transform was applied to the signal to extract the pure roll motion. The results were compared to those of the Fourier transform. DWT was able to decouple the two signals efficiently while the Fourier transform was not.

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Robust Design of a Discrete System Using Taguchi's Standard Signal-to-Noise Ratio (다구치의 표준 SN비를 이용한 이산형 시스템의 로버스트설계)

  • Kim, Seong-Jun
    • Journal of Korean Society for Quality Management
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    • v.27 no.2
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    • pp.101-111
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    • 1999
  • The purpose of Taguchi's robust design lies in quality improvement by making the performance of a system robust against noise. Robust design with continuous performance characteristics has been the subject of much interest. However relatively little work has been done for discrete characteristics such as 0-1, good-medium-bad, etc. This paper is concerned with robust design of a discrete dynamic system. We first investigate the Taguchi method for robust design with discrete dynamic characteristics and discuss his standard error probability (SEP). Then we propose a generalized SEP, which makes it possible to encompass a wider class of robust design problems. An illustration is also given by example.

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Parallel Processing Implementation of Discrete Hartley Transform using Systolic Array Processor Architecture (Systolic Array Processor Architecture를 이용한 Discrete Hartley Transform 의 병렬 처리 실행)

  • Kang, J.K.;Joo, C.H.;Choi, J.S.
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.14-16
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    • 1988
  • With the development of VLSI technology, research on special processors for high-speed processing is on the increase and studies are focused on designing VLSI-oriented processors for signal processing. This paper processes a one-dimensional systolic array for Discrete Hartley Transform implementation and also processes processing element which is well described for algorithm. The discrete Hartley Transform(DHT) is a real-valued transform closely related to the DFT of a real-valued sequence can be exploited to reduce both the storage and the computation requried to produce the transform of real-valued sequence to a real-valued spectrum while preserving some of the useful properties of the DFT is something preferred. Finally, the architecture of one-dimensional 8-point systolic array, the detailed diagram of PE, total time units concept on implementation this arrays, and modularity are described.

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Modeling of The Fuzzy Discrete Event System and It s Application (퍼지 이산사건 시스템의 모델링과 응용)

  • Kim, Jin-Kwon;Kim, Jung-Chul;Hwang, Hyung-Soo
    • Journal of the Korean Institute of Intelligent Systems
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    • v.14 no.4
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    • pp.487-492
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    • 2004
  • This paper deals with modeling method and application of Fuzzy Discrete Event System(FDES). FDES have characteristics which Crisp Discrete Event System(CDES) can't deals with and is constituted with the events that is determined by vague and uncertain judgement like biomedical or traffic control. In general, the modeling method of CDES has been studied many times, but that of FDES hasn't been nearly studied by qualitative character and scarcity of applicated system. This paper models traffic system with FDES's character in FTTPN and designs a traffic signal controller.

The Digital Image Processing Method Using Triple-Density Discrete Wavelet Transformation (3중 밀도 이산 웨이브렛 변환을 이용한 디지털 영상처리 기법)

  • Shin, Jong Hong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.3
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    • pp.133-145
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    • 2012
  • This paper describes the high density discrete wavelet transformation which is one that expands an N point signal to M transform coefficients with M > N. The double-density discrete wavelet transform is one of the high density discrete wavelet transformation. This transformation employs one scaling function and two distinct wavelets, which are designed to be offset from one another by one half. And it is nearly shift-invariant. Similarly, triple-density discrete wavelet transformation is a new set of dyadic wavelet transformation with two generators. The construction provides a higher sampling in both time and frequency. Specifically, the spectrum of the first wavelet is concentrated halfway between the spectrum of the second wavelet and the spectrum of its dilated version. In addition, the second wavelet is translated by half-integers rather than whole-integers in the frame construction. This arrangement leads to high density wavelet transformation. But this new transform is approximately shift-invariant and has intermediate scales. In two dimensions, this transform outperforms the standard and double-density discrete wavelet transformation in terms of multiple directions. Resultingly, the proposed wavelet transformation services good performance in image and video processing fields.

Lung Sound Classification Using Hjorth Descriptor Measurement on Wavelet Sub-bands

  • Rizal, Achmad;Hidayat, Risanuri;Nugroho, Hanung Adi
    • Journal of Information Processing Systems
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    • v.15 no.5
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    • pp.1068-1081
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    • 2019
  • Signal complexity is one point of view to analyze the biological signal. It arises as a result of the physiological signal produced by biological systems. Signal complexity can be used as a method in extracting the feature for a biological signal to differentiate a pathological signal from a normal signal. In this research, Hjorth descriptors, one of the signal complexity measurement techniques, were measured on signal sub-band as the features for lung sounds classification. Lung sound signal was decomposed using two wavelet analyses: discrete wavelet transform (DWT) and wavelet packet decomposition (WPD). Meanwhile, multi-layer perceptron and N-fold cross-validation were used in the classification stage. Using DWT, the highest accuracy was obtained at 97.98%, while using WPD, the highest one was found at 98.99%. This result was found better than the multi-scale Hjorth descriptor as in previous studies.