• Title/Summary/Keyword: wavelet function

Search Result 408, Processing Time 0.027 seconds

Design of the Structure for Scaling-Wavelet Neural Network Using Genetic Algorithm (유전 알고리즘을 이용한 스케일링-웨이블릿 복합 신경회로망 구조 설계)

  • 김성주;서재용;연정흠;김성현;전홍태
    • Proceedings of the IEEK Conference
    • /
    • 2001.06c
    • /
    • pp.25-28
    • /
    • 2001
  • RBFN has some problem that because the basis function isn't orthogonal to each others the number of used basis function goes to big. In this reason, the Wavelet Neural Network which uses the orthogonal basis function in the hidden node appears. In this paper, we propose the composition method of the actual function in hidden layer with the scaling function which can represent the region by which the several wavelet can be represented. In this method, we can decrease the size of the network with the pure several wavelet function. In addition to, when we determine the parameters of the scaling function we can process rough approximation and then the network becomes more stable. The other wavelets can be determined by the global solutions which is suitable for the suggested problem using the genetic algorithm and also, we use the back-propagation algorithm in the learning of the weights. In this step, we approximate the target function with fine tuning level. The complex neural network suggested In this paper is a new structure and important simultaneously in the point of handling the determination problem in the wavelet initialization.

  • PDF

Adaptive High-order Variation De-noising Method for Edge Detection with Wavelet Coefficients

  • Chenghua Liu;Anhong Wang
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.17 no.2
    • /
    • pp.412-434
    • /
    • 2023
  • This study discusses the high-order diffusion method in the wavelet domain. It aims to improve the edge protection capability of the high-order diffusion method using wavelet coefficients that can reflect image information. During the first step of the proposed diffusion method, the wavelet packet decomposition is a more refined decomposition method that can extract the texture and structure information of the image at different resolution levels. The high-frequency wavelet coefficients are then used to construct the edge detection function. Subsequently, because accurate wavelet coefficients can more accurately reflect the edges and details of the image information, by introducing the idea of state weight, a scheme for recovering wavelet coefficients is proposed. Finally, the edge detection function is constructed by the module of the wavelet coefficients to guide high-order diffusion, the denoised image is obtained. The experimental results showed that the method presented in this study improves the denoising ability of the high-order diffusion model, and the edge protection index (SSIM) outperforms the main methods, including the block matching and 3D collaborative filtering (BM3D) and the deep learning-based image processing methods. For images with rich textural details, the present method improves the clarity of the obtained images and the completeness of the edges, demonstrating its advantages in denoising and edge protection.

Analysis of the Vibration of High Speed Trains and the Irregularity of Railway Using a Wavelet-based Frequency Response Function (웨이브렛 기반 주파수 응답함수를 이용한 고속철도차량의 진동 및 궤도불규칙 특성 분석)

  • Lee, Jun-Seok;Choi, Sung-Hoon;Kim, Sang-Soo;Park, Choon-Soo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2008.04a
    • /
    • pp.766-771
    • /
    • 2008
  • In this paper, the vibration of high speed trains and the irregularity of railway are examined using a wavelet-based frequency response function. To investigate their characteristics, non-stationary acceleration data are acquired and processed using the wavelet transform. Also, the railway irregularity is examined by acquiring the data from the on-board laser-based measurement system. The correlation between the train vibration and the railway irregularity has been investigated. From the analysis, the wavelet-based frequency response function is a promised method for the dynamic characteristics of high speed trains.

  • PDF

Rotation-invariant pattern recognition using an optical wavelet circular harmonic matched filter (광웨이브렛 원형고조 정합필터를 이용한 회전불변 패턴인식)

  • 이하운;김철수;김정우;김수중
    • Journal of the Korean Institute of Telematics and Electronics S
    • /
    • v.34S no.1
    • /
    • pp.132-144
    • /
    • 1997
  • The rotation-invariant pattern recognition filter using circular harmonic function of the wavelet transforme dsreference image by morlet, mexican-hat, and haar wavelt function is proposed. The rotated reference images, the images sililar to the reference image, and the images which are added by random noise are used for the inpt images, and in case of the input images with random noise, they are applied to the recognition after removing the random noise by the transformed moving average method with proper thresholding value and window size. The proposed optical wavelet circular harmonic matched filter (WCHMF) is a type of the matche dfilter, so that it can be applied to the 4f vander lugt optical correlation system. SNR and discrimination capability of the proposed filter are compared with those of the conventional HF, the POCHF, and the BPOCHF. The proper wavelet function for the reference image used in this paper is achieved by applying morlet, mexican-hat, and harr wavelet function ot the proposed filter, and the proposed filter has good SNR and discrimination capability with rotation-invariance in case of the morlet wavelet function.

  • PDF

ORTHOGONAL TWO-DIRECTION REFINABLE FUNCTION OF ORDER 3

  • KWON, SOON-GEOL
    • Journal of applied mathematics & informatics
    • /
    • v.37 no.3_4
    • /
    • pp.307-315
    • /
    • 2019
  • In this paper we construct orthogonal two-direction scaling function of order 3 and corresponding wavelet function. In this paper we propose a different approach using orthogonal symmetric/antisymmetric multiwavelets of order 3. An example for constructing orthogonal two-direction scaling function of order 3 and corresponding wavelet function is given.

Wavelet Shift Keying System Using a Binary Matching Filter (2진 정합필터를 이용한 웨이브릿 편이변조 시스템)

  • Oh, Hyoung-Jin;Jeong, Tae-Il;Lee, Tae-Oh
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.12 no.11
    • /
    • pp.1933-1938
    • /
    • 2008
  • There are the frequency shift keying(FSK), phase shift keying(PSK) and amplitude shift keying(ASK) in the conventional digital communications method. In this parer, We proposed the algorithm for wavelet shift keying system using a binary matching filter in the digital communication. Wavelet shift keying system are used to a scaling function(low frequency) and wavelet(high frequency) coefficients. The binary data is encoded by modulator which assigned the scaling function to 1(one), and wavelet to zero(0). Wavelet shift keying of the conventional method needs to a post-processing for the decoding. In this paper, wavelet shift keying signal is reconstructed by the decoder using a binary matching filter. So, it was able to the decoding without the post-processing. It was demonstrated by the experiment that the proposed algorithm is a validity.

A Study on Fuzzy Wavelet Basis Function for Image Interpolation

  • Byun, Oh-Sung;Moon, Sung-Ryong
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.4 no.3
    • /
    • pp.266-270
    • /
    • 2004
  • The image interpolation is one of an image preprocessing process to heighten a resolution. The conventional image interpolation used much to concept that it put in other pixel to select the nearest value in a pixel simply, and use much the temporal object interpolation techniques to do the image interpolation by detecting motion in a moving picture presently. In this paper, it is proposed the image interpolation techniques using the fuzzy wavelet base function. This is applied to embody a correct edge image and a natural image when expand part of the still image by applying the fuzzy wavelet base function coefficient to the conventional B-spline function. And the proposal algorithm in this paper is confirmed to improve about 1.2831 than the image applying the conventional B-spline function through the computer simulation.

Wavelet Generation and It's Application in Gravity Potential (중력 포텐셜에서의 웨이브렛 생성과 응용)

  • Kim, Sam-Tai;Jin, Hong-Sung;Rim, Hyoung-Rae
    • Journal of the Korean earth science society
    • /
    • v.25 no.2
    • /
    • pp.109-114
    • /
    • 2004
  • A wavelet method is applied to the analysis of gravity potential. One scaling function is proposed to generate wavelet. The scaling function is shown to be replaced to the Green’s function in gravity potential. The upward continuation can be expressed as a wavelet transform i.e. convolution with the scaling function. The scaling factor indicates the height variation. The multiscale edge detection is carried by connecting the local maxima of the wavelet transform at scales. The multiscale edge represents discontinuity of the geological structure. The multiscale edge method is applied to gravity data from Masan and Changwon.

A Study on Translation-Invariant Wavelet De-Noising with Multi-Thresholding Function (다중 임계치 함수의 TI 웨이브렛 잡음제거 기법)

  • Choi, Jae-Yong
    • The Journal of the Acoustical Society of Korea
    • /
    • v.25 no.7
    • /
    • pp.333-338
    • /
    • 2006
  • This paper proposes an improved do-noising method using multi-thresholding function based on translation-invariant (W) wavelet proposed by Donoho et al. for underwater radiated noise measurement. The traditional wavelet thresholding de-noising method causes Pseudo-Gibbs phenomena near singularities due to discrete wavelet transform. In order to suppress Pseudo-Gibbs Phenomena, a do-noising method combining multi-thresholding function with the translation-invariant wavelet transform is proposed in this paper. The multi-thresholding function is a modified soft-thresholding to each node according to the discriminated threshold so as to reject かon external noise and white gaussian noise. It is verified by numerical simulation. And the experimental results are confirmed through sea-trial using multi-single sensors.