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[Keyword] Support Vector Regression(11hit)

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  • Study on Wear Debris Distribution and Performance Degradation in Low Frequency Fretting Wear of Electrical Connector

    Yanyan LUO  Jingzhao AN  Jingyuan SU  Zhaopan ZHANG  Yaxin DUAN  

     
    PAPER-Electromechanical Devices and Components

      Pubricized:
    2022/10/13
      Vol:
    E106-C No:3
      Page(s):
    93-102

    Aiming at the problem of the deterioration of the contact performance caused by the wear debris generated during the fretting wear of the electrical connector, low-frequency fretting wear experiments were carried out on the contacts of electrical connectors, the accumulation and distribution of the wear debris were detected by the electrical capacitance tomography technology; the influence of fretting cycles, vibration direction, vibration frequency and vibration amplitude on the accumulation and distribution of wear debris were analyzed; the correlation between characteristic value of wear debris and contact resistance value was studied, and a performance degradation model based on the accumulation and distribution of wear debris was built. The results show that fretting wear and performance degradation are the most serious in axial vibration; the characteristic value of wear debris and contact resistance are positively correlated with the fretting cycles, vibration frequency and vibration amplitude; there is a strong correlation between the sum of characteristic value of wear debris and the contact resistance value; the prediction error of ABC-SVR model of fretting wear performance degradation of electrical connectors constructed by the characteristic value of wear debris is less than 6%. Therefore, the characteristic value of wear debris in contact subareas can quantitatively describe the degree of fretting wear and the process of performance degradation.

  • Programmable Analog Calculation Unit with Two-Stage Architecture: A Solution of Efficient Vector-Computation Open Access

    Renyuan ZHANG  Takashi NAKADA  Yasuhiko NAKASHIMA  

     
    PAPER

      Vol:
    E102-A No:7
      Page(s):
    878-885

    A programmable analog calculation unit (ACU) is designed for vector computations in continuous-time with compact circuit scale. From our early study, it is feasible to retrieve arbitrary two-variable functions through support vector regression (SVR) in silicon. In this work, the dimensions of regression are expanded for vector computations. However, the hardware cost and computing error greatly increase along with the expansion of dimensions. A two-stage architecture is proposed to organize multiple ACUs for high dimensional regression. The computation of high dimensional vectors is separated into several computations of lower dimensional vectors, which are implemented by the free combination of several ACUs with lower cost. In this manner, the circuit scale and regression error are reduced. The proof-of-concept ACU is designed and simulated in a 0.18μm technology. From the circuit simulation results, all the demonstrated calculations with nine operands are executed without iterative clock cycles by 4960 transistors. The calculation error of example functions is below 8.7%.

  • Low Bit-Rate Compression Image Restoration through Subspace Joint Regression Learning

    Zongliang GAN  

     
    LETTER-Image Processing and Video Processing

      Pubricized:
    2018/06/28
      Vol:
    E101-D No:10
      Page(s):
    2539-2542

    In this letter, an effective low bit-rate image restoration method is proposed, in which image denoising and subspace regression learning are combined. The proposed framework has two parts: image main structure estimation by classical NLM denoising and texture component prediction by subspace joint regression learning. The local regression function are learned from denoised patch to original patch in each subspace, where the corresponding compression image patches are employed to generate anchoring points by the dictionary learning approach. Moreover, we extent Extreme Support Vector Regression (ESVR) as multi-variable nonlinear regression to get more robustness results. Experimental results demonstrate the proposed method achieves favorable performance compared with other leading methods.

  • Blind Source Separation and Equalization Based on Support Vector Regression for MIMO Systems

    Chao SUN  Ling YANG  Juan DU  Fenggang SUN  Li CHEN  Haipeng XI  Shenglei DU  

     
    PAPER-Fundamental Theories for Communications

      Pubricized:
    2017/08/28
      Vol:
    E101-B No:3
      Page(s):
    698-708

    In this paper, we first propose two batch blind source separation and equalization algorithms based on support vector regression (SVR) for linear time-invariant multiple input multiple output (MIMO) systems. The proposed algorithms combine the conventional cost function of SVR with error functions of classical on-line algorithm for blind equalization: both error functions of constant modulus algorithm (CMA) and radius directed algorithm (RDA) are contained in the penalty term of SVR. To recover all sources simultaneously, the cross-correlations of equalizer outputs are included in the cost functions. Simulation experiments show that the proposed algorithms can recover all sources successfully and compensate channel distortion simultaneously. With the use of iterative re-weighted least square (IRWLS) solution of SVR, the proposed algorithms exhibit low computational complexity. Compared with traditional algorithms, the new algorithms only require fewer samples to achieve convergence and perform a lower residual interference. For multilevel signals, the single algorithms based on constant modulus property usually show a relatively high residual error, then we propose two dual-mode blind source separation and equalization schemes. Between them, the dual-mode scheme based on SVR merely requires fewer samples to achieve convergence and further reduces the residual interference.

  • Channel Impulse Response Measurements-Based Location Estimation Using Kernel Principal Component Analysis

    Zhigang CHEN  Xiaolei ZHANG  Hussain KHURRAM  He HUANG  Guomei ZHANG  

     
    LETTER-Digital Signal Processing

      Vol:
    E99-A No:10
      Page(s):
    1876-1880

    In this letter, a novel channel impulse response (CIR)-based fingerprinting positioning method using kernel principal component analysis (KPCA) has been proposed. During the offline phase of the proposed method, a survey is performed to collect all CIRs from access points, and a fingerprint database is constructed, which has vectors including CIR and physical location. During the online phase, KPCA is first employed to solve the nonlinearity and complexity in the CIR-position dependencies and extract the principal nonlinear features in CIRs, and support vector regression is then used to adaptively learn the regress function between the KPCA components and physical locations. In addition, the iterative narrowing-scope step is further used to refine the estimation. The performance comparison shows that the proposed method outperforms the traditional received signal strength based positioning methods.

  • A Speech Intelligibility Estimation Method Using a Non-reference Feature Set

    Toshihiro SAKANO  Yosuke KOBAYASHI  Kazuhiro KONDO  

     
    PAPER

      Vol:
    E98-D No:1
      Page(s):
    21-28

    We proposed and evaluated a speech intelligibility estimation method that does not require a clean speech reference signal. The propose method uses the features defined in the ITU-T standard P.563, which estimates the overall quality of speech without the reference signal. We selected two sets of features from the P.563 features; the basic 9-feature set, which includes basic features that characterize both speech and background noise, e.g., cepstrum skewness and LPC kurtosis, and the extended 31-feature set with 22 additional features for a more accurate description of the degraded speech and noise, e.g., SNR, average pitch, and spectral clarity among others. Four hundred noise samples were added to speech, and about 70% of these samples were used to train a support vector regression (SVR) model. The trained models were used to estimate the intelligibility of speech degraded by added noise. The proposed method showed a root mean square error (RMSE) value of about 10% and correlation with subjective intelligibility of about 0.93 for speech distorted with known noise type, and RMSE of about 16% and a correlation of about 0.84 for speech distorted with unknown noise type, both with either the 9 or the 31-dimension feature set. These results were higher than the estimation using frequency-weighed SNR calculated in critical frequency bands, which requires the clean reference signal for its calculation. We believe this level of accuracy proves the proposed method to be applicable to real-time speech quality monitoring in the field.

  • Analytical Modeling of Network Throughput Prediction on the Internet

    Chunghan LEE  Hirotake ABE  Toshio HIROTSU  Kyoji UMEMURA  

     
    PAPER-Network and Communication

      Vol:
    E95-D No:12
      Page(s):
    2870-2878

    Predicting network throughput is important for network-aware applications. Network throughput depends on a number of factors, and many throughput prediction methods have been proposed. However, many of these methods are suffering from the fact that a distribution of traffic fluctuation is unclear and the scale and the bandwidth of networks are rapidly increasing. Furthermore, virtual machines are used as platforms in many network research and services fields, and they can affect network measurement. A prediction method that uses pairs of differently sized connections has been proposed. This method, which we call connection pair, features a small probe transfer using the TCP that can be used to predict the throughput of a large data transfer. We focus on measurements, analyses, and modeling for precise prediction results. We first clarified that the actual throughput for the connection pair is non-linearly and monotonically changed with noise. Second, we built a previously proposed predictor using the same training data sets as for our proposed method, and it was unsuitable for considering the above characteristics. We propose a throughput prediction method based on the connection pair that uses ν-support vector regression and the polynomial kernel to deal with prediction models represented as a non-linear and continuous monotonic function. The prediction results of our method compared to those of the previous predictor are more accurate. Moreover, under an unstable network state, the drop in accuracy is also smaller than that of the previous predictor.

  • Identification of Quasi-ARX Neurofuzzy Model with an SVR and GA Approach

    Yu CHENG  Lan WANG  Jinglu HU  

     
    PAPER-Systems and Control

      Vol:
    E95-A No:5
      Page(s):
    876-883

    The quasi-ARX neurofuzzy (Q-ARX-NF) model has shown great approximation ability and usefulness in nonlinear system identification and control. It owns an ARX-like linear structure, and the coefficients are expressed by an incorporated neurofuzzy (InNF) network. However, the Q-ARX-NF model suffers from curse-of-dimensionality problem, because the number of fuzzy rules in the InNF network increases exponentially with input space dimension. It may result in high computational complexity and over-fitting. In this paper, the curse-of-dimensionality is solved in two ways. Firstly, a support vector regression (SVR) based approach is used to reduce computational complexity by a dual form of quadratic programming (QP) optimization, where the solution is independent of input dimensions. Secondly, genetic algorithm (GA) based input selection is applied with a novel fitness evaluation function, and a parsimonious model structure is generated with only important inputs for the InNF network. Mathematical and real system simulations are carried out to demonstrate the effectiveness of the proposed method.

  • Image Quality Enhancement for Single-Image Super Resolution Based on Local Similarities and Support Vector Regression

    Atsushi YAGUCHI  Tadaaki HOSAKA  Takayuki HAMAMOTO  

     
    LETTER-Processing

      Vol:
    E94-A No:2
      Page(s):
    552-554

    In reconstruction-based super resolution, a high-resolution image is estimated using multiple low-resolution images with sub-pixel misalignments. Therefore, when only one low-resolution image is available, it is generally difficult to obtain a favorable image. This letter proposes a method for overcoming this difficulty for single- image super resolution. In our method, after interpolating pixel values at sub-pixel locations on a patch-by-patch basis by support vector regression, in which learning samples are collected within the given image based on local similarities, we solve the regularized reconstruction problem with a sufficient number of constraints. Evaluation experiments were performed for artificial and natural images, and the obtained high-resolution images indicate the high-frequency components favorably along with improved PSNRs.

  • Edge-Based Color Constancy via Support Vector Regression

    Ning WANG  De XU  Bing LI  

     
    LETTER-Image Recognition, Computer Vision

      Vol:
    E92-D No:11
      Page(s):
    2279-2282

    Color constancy is the ability to measure colors of objects independent of the light source color. Various methods have been proposed to handle this problem. Most of them depend on the statistical distributions of the pixel values. Recent studies show that incorporation image derivatives are more effective than the direct use of pixel values. Based on this idea, a novel edge-based color constancy algorithm using support vector regression (SVR) is proposed. Contrary to existing SVR color constancy algorithm, which is computed from the zero-order structure of images, our method is based on the higher-order structure of images. The experimental results show that our algorithm is more effective than the zero-order SVR color constancy methods.

  • Detection of Overlapping Speech in Meetings Using Support Vector Machines and Support Vector Regression

    Kiyoshi YAMAMOTO  Futoshi ASANO  Takeshi YAMADA  Nobuhiko KITAWAKI  

     
    PAPER-Engineering Acoustics

      Vol:
    E89-A No:8
      Page(s):
    2158-2165

    In this paper, a method of detecting overlapping speech segments in meetings is proposed. It is known that the eigenvalue distribution of the spatial correlation matrix calculated from a multiple microphone input reflects information on the number and relative power of sound sources. However, in a reverberant sound field, the feature of the number of sources in the eigenvalue distribution is degraded by the room reverberation. In the Support Vector Machines approach, the eigenvalue distribution is classified into two classes (overlapping speech segments and single speech segments). In the Support Vector Regression approach, the relative power of sound sources is estimated by using the eigenvalue distribution, and overlapping speech segments are detected based on the estimated relative power. The salient feature of this approach is that the sensitivity of detecting overlapping speech segments can be controlled simply by changing the threshold value of the relative power. The proposed method was evaluated using recorded data of an actual meeting.