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[Author] Yan ZHANG(15hit)

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  • CCP-Based Plant-Wide Optimization and Application to the Walking-Beam-Type Reheating Furnace

    Yan ZHANG  Hongyan MAO  

     
    PAPER-Fundamentals of Information Systems

      Pubricized:
    2016/06/17
      Vol:
    E99-D No:9
      Page(s):
    2239-2247

    In this paper, the integration of dynamic plant-wide optimization and distributed generalized predictive control (DGPC) is presented for serially connected processes. On the top layer, chance-constrained programming (CCP) is employed in the plant-wide optimization with economic and model uncertainties, in which the constraints containing stochastic parameters are guaranteed to be satisfied at a high level of probability. The deterministic equivalents are derived for linear and nonlinear individual chance constraints, and an algorithm is developed to search for the solution to the joint probability constrained problem. On the lower layer, the distributed GPC method based on neighborhood optimization with one-step delay communication is developed for on-line control of the whole system. Simulation studies for furnace temperature set-points optimization problem of the walking-beam-type reheating furnace are illustrated to verify the effectiveness and practicality of the proposed scheme.

  • Exploring the Outer Boundary of a Simple Polygon

    Qi WEI  Xiaolin YAO  Luan LIU  Yan ZHANG  

     
    PAPER-Fundamentals of Information Systems

      Pubricized:
    2021/04/02
      Vol:
    E104-D No:7
      Page(s):
    923-930

    We investigate an online problem of a robot exploring the outer boundary of an unknown simple polygon P. The robot starts from a specified vertex s and walks an exploration tour outside P. It has to see all points of the polygon's outer boundary and to return to the start. We provide lower and upper bounds on the ratio of the distance traveled by the robot in comparison to the length of the shortest path. We consider P in two scenarios: convex polygon and concave polygon. For the first scenario, we prove a lower bound of 5 and propose a 23.78-competitive strategy. For the second scenario, we prove a lower bound of 5.03 and propose a 26.5-competitive strategy.

  • TCP Flow Level Performance Evaluation on Error Rate Aware Scheduling Algorithms in Evolved UTRA and UTRAN Networks

    Yan ZHANG  Masato UCHIDA  Masato TSURU  Yuji OIE  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E91-B No:3
      Page(s):
    761-771

    We present a TCP flow level performance evaluation on error rate aware scheduling algorithms in Evolved UTRA and UTRAN networks. With the introduction of the error rate, which is the probability of transmission failure under a given wireless condition and the instantaneous transmission rate, the transmission efficiency can be improved without sacrificing the balance between system performance and user fairness. The performance comparison with and without error rate awareness is carried out dependant on various TCP traffic models, user channel conditions, schedulers with different fairness constraints, and automatic repeat request (ARQ) types. The results indicate that error rate awareness can make the resource allocation more reasonable and effectively improve the system and individual performance, especially for poor channel condition users.

  • Radar Constant-Modulus Waveform Design for Multiple Extended Targets

    Wenzhen YUE  Yan ZHANG  Jingwen XIE  

     
    LETTER-Digital Signal Processing

      Vol:
    E100-A No:3
      Page(s):
    888-892

    The problem of radar constant-modulus (CM) waveform design for the detection of multiple targets is considered in this paper. The CM constraint is imposed from the perspective of hardware realization and full utilization of the transmitter's power. Two types of CM waveforms — the arbitrary-phase waveform and the quadrature phase shift keying waveform — are obtained by maximizing the minimum of the signal-to-clutter-plus-noise ratios of the various targets. Numerical results show that the designed CM waveforms perform satisfactorily, even when compared with their counterparts without constraints on the peak-to-average ratio.

  • SEM Image Quality Assessment Based on Texture Inpainting

    Zhaolin LU  Ziyan ZHANG  Yi WANG  Liang DONG  Song LIANG  

     
    LETTER-Image Processing and Video Processing

      Pubricized:
    2020/10/30
      Vol:
    E104-D No:2
      Page(s):
    341-345

    This letter presents an image quality assessment (IQA) metric for scanning electron microscopy (SEM) images based on texture inpainting. Inspired by the observation that the texture information of SEM images is quite sensitive to distortions, a texture inpainting network is first trained to extract texture features. Then the weights of the trained texture inpainting network are transferred to the IQA network to help it learn an effective texture representation of the distorted image. Finally, supervised fine-tuning is conducted on the IQA network to predict the image quality score. Experimental results on the SEM image quality dataset demonstrate the advantages of the presented method.

  • MCFO Compensation and Performance Analysis for Localized DFT-S-OFDM Uplink Cooperative System

    Zhiyan ZHANG  Jianhua ZHANG  Wei XU  Yanyan ZHANG  Yi LIU  

     
    LETTER-Transmission Systems and Transmission Equipment for Communications

      Vol:
    E94-B No:1
      Page(s):
    285-289

    In the localized Discrete Fourier Transform-Spread-Orthogonal Frequency Division Multiplexing (DFT-S-OFDM) uplink cooperative system, multiple carrier frequency offsets (MCFO), arising from the nodes' separate oscillators and Doppler spreads, drastically degrade the performance of the receiver. To solve the problem, this letter proposes an efficient MCFO compensation method which fully exploits the diversity gain of space frequency block coded (SFBC) and the characteristic of inter-carrier interference (ICI). Moreover, the bit error ratio (BER) lower bound of the proposed algorithm is theoretically derived. Simulation results validate the theoretical analysis and demonstrate that the proposed MCFO compensation method can achieve robust BER performance in a wide range of MCFO in the multipath Rayleigh fading channel.

  • Receiver Differential Code Bias Estimation under Disturbed Ionosphere Status Using Linear Planar Model Based Minimum Standard Deviation Searching Method with Bias Detection Open Access

    Yan ZHANG  Lei CHEN  Xiaomei TANG  Gang OU  

     
    PAPER-Satellite Communications

      Pubricized:
    2019/09/20
      Vol:
    E103-B No:3
      Page(s):
    272-282

    Differential code biases (DCBs) are important parameters that must be estimated accurately for precise positioning and Satellite Based Augmentation Systems (SBAS) ionospheric related parameter generation. In this paper, in order to solve the performance degradation problem of the traditional minimum STD searching algorithm in disturbed ionosphere status and in geomagnetic low latitudes, we propose a linear planar based minimum STD searching algorithm. Firstly, we demonstrate the linear planar trend of the local vertical TEC and introduce the linear planar model based minimum standard variance searching method. Secondly, we validate the correctness of our proposed method through theoretical analysis and propose bias detection to avoid large estimation bias. At last, we show the performance of our proposed method under different geomagnetic latitudes, different seasons and different ionosphere status. The experimental results show that for the traditional minimum STD searching algorithm based on constant model, latitude difference is the key factor affecting the performance of DCB estimation. The DCB estimation performance in geomagnetic mid latitudes is the best, followed by the high latitudes and the worst is for the low latitudes. While the algorithm proposed in this paper can effectively solve the performance degradation problem of DCB estimation in geomagnetic low latitudes by using the linear planar model which is with a higher degree of freedom to model the local ionosphere characteristics and design dJ to screen the epochs. Through the analysis of the DCB estimation results of a large number of stations, it can be found that the probability of large estimation deviation of the traditional method will increase obviously under the disturb ionosphere conditions, but the algorithm we proposed can effectively control the amplitude of the maximum deviation and alleviate the probability of large estimation deviation in disturb ionosphere status.

  • A Constructive Method of Algebraic Attack with Less Keystream Bits

    Xiaoyan ZHANG  Qichun WANG  Bin WANG  Haibin KAN  

     
    LETTER-Cryptography and Information Security

      Vol:
    E94-A No:10
      Page(s):
    2059-2062

    In algebraic attack on stream ciphers based on LFSRs, the secret key is found by solving an overdefined system of multivariate equations. There are many known algorithms from different point of view to solve the problem, such as linearization, relinearization, XL and Grobner Basis. The simplest method, linearization, treats each monomial of different degrees as a new variable, and consists of variables (the degree of the system of equations is denoted by d). Thus it needs at least equations, i.e. keystream bits to recover the secret key by Gaussian reduction or other. In this paper we firstly propose a concept, called equivalence of LFSRs. On the basis of it, we present a constructive method that can solve an overdefined system of multivariate equations with less keystream bits by extending the primitive polynomial.

  • Adaptive Object Tracking with Complementary Models

    Peng GAO  Yipeng MA  Chao LI  Ke SONG  Yan ZHANG  Fei WANG  Liyi XIAO  

     
    LETTER-Image Recognition, Computer Vision

      Pubricized:
    2018/08/06
      Vol:
    E101-D No:11
      Page(s):
    2849-2854

    Most state-of-the-art discriminative tracking approaches are based on either template appearance models or statistical appearance models. Despite template appearance models have shown excellent performance, they perform poorly when the target appearance changes rapidly. In contrast, statistic appearance models are insensitive to fast target state changes, but they yield inferior tracking results in challenging scenarios such as illumination variations and background clutters. In this paper, we propose an adaptive object tracking approach with complementary models based on template and statistical appearance models. Both of these models are unified via our novel combination strategy. In addition, we introduce an efficient update scheme to improve the performance of our approach. Experimental results demonstrate that our approach achieves superior performance at speeds that far exceed the frame-rate requirement on recent tracking benchmarks.

  • RMF-Net: Improving Object Detection with Multi-Scale Strategy

    Yanyan ZHANG  Meiling SHEN  Wensheng YANG  

     
    PAPER-Multimedia Systems for Communications

      Pubricized:
    2021/12/02
      Vol:
    E105-B No:5
      Page(s):
    675-683

    We propose a target detection network (RMF-Net) based on the multi-scale strategy to solve the problems of large differences in the detection scale and mutual occlusion, which result in inaccurate locations. A multi-layer feature fusion module and multi-expansion dilated convolution pyramid module were designed based on the ResNet-101 residual network. The ability of the network to express the multi-scale features of the target could be improved by combining the shallow and deep features of the target and expanding the receptive field of the network. Moreover, RoI Align pooling was introduced to reduce the low accuracy of the anchor frame caused by multiple quantizations for improved positioning accuracy. Finally, an AD-IoU loss function was designed, which can adaptively optimise the distance between the prediction box and real box by comprehensively considering the overlap rate, centre distance, and aspect ratio between the boxes and can improve the detection accuracy of the occlusion target. Ablation experiments on the RMF-Net model verified the effectiveness of each factor in improving the network detection accuracy. Comparative experiments were conducted on the Pascal VOC2007 and Pascal VOC2012 datasets with various target detection algorithms based on convolutional neural networks. The results demonstrated that RMF-Net exhibited strong scale adaptability at different occlusion rates. The detection accuracy reached 80.4% and 78.5% respectively.

  • Community Discovery on Multi-View Social Networks via Joint Regularized Nonnegative Matrix Triple Factorization

    Liangliang ZHANG  Longqi YANG  Yong GONG  Zhisong PAN  Yanyan ZHANG  Guyu HU  

     
    PAPER-Artificial Intelligence, Data Mining

      Pubricized:
    2017/03/21
      Vol:
    E100-D No:6
      Page(s):
    1262-1270

    In multi-view social networks field, a flexible Nonnegative Matrix Factorization (NMF) based framework is proposed which integrates multi-view relation data and feature data for community discovery. Benefit with a relaxed pairwise regularization and a novel orthogonal regularization, it outperforms the-state-of-art algorithms on five real-world datasets in terms of accuracy and NMI.

  • A Two-Stage Crack Detection Method for Concrete Bridges Using Convolutional Neural Networks

    Yundong LI  Weigang ZHAO  Xueyan ZHANG  Qichen ZHOU  

     
    LETTER-Artificial Intelligence, Data Mining

      Pubricized:
    2018/09/05
      Vol:
    E101-D No:12
      Page(s):
    3249-3252

    Crack detection is a vital task to maintain a bridge's health and safety condition. Traditional computer-vision based methods easily suffer from disturbance of noise and clutters for a real bridge inspection. To address this limitation, we propose a two-stage crack detection approach based on Convolutional Neural Networks (CNN) in this letter. A predictor of small receptive field is exploited in the first detection stage, while another predictor of large receptive field is used to refine the detection results in the second stage. Benefiting from data fusion of confidence maps produced by both predictors, our method can predict the probability belongs to cracked areas of each pixel accurately. Experimental results show that the proposed method is superior to an up-to-date method on real concrete surface images.

  • Interference-Aware Power Control for Relay-Enhanced Multicell Networks

    Xiaoyan HUANG  Yuming MAO  Supeng LENG  Yan ZHANG  Qin YU  

     
    PAPER-Wireless Communication Technologies

      Vol:
    E95-B No:12
      Page(s):
    3845-3854

    This paper focuses on power control in relay-enhanced multicell networks with universal frequency reuse for maximizing the overall system throughput, subject to interference and noise impairments, and individual power constraints at both BSs and RSs. With a high signal-to-interference-plus-noise ratio (SINR) approximation, an energy efficiency based power allocation algorithm is proposed to achieve the maximum sum throughput with the least power consumption. Moreover, an iterative quasi-distributed power allocation algorithm is also presented, which is suitable for any SINR regime. Numerical results indicate that the proposed algorithms approach the optimal power allocation and the system performance can be significantly improved in terms of network throughput and energy efficiency.

  • A Spectral Analyzer Based on Dual Coprime DFT Filter Banks and Sub-Decimation

    Xueyan ZHANG  Libin QU  Zhangkai LUO  

     
    PAPER-Fundamental Theories for Communications

      Pubricized:
    2021/06/23
      Vol:
    E105-B No:1
      Page(s):
    11-20

    Coprime (pair of) DFT filter banks (coprime DFTFB), which process signals like a spectral analyzer in time domain, divides the power spectrum equally into MN bands by employing two DFT filter banks (DFTFBs) of size only M and N respectively, where M and N are coprime integers. With coprime DFTFB, frequencies in wide sense stationary (WSS) signals can be effectively estimated with a much lower sampling rates than the Nyquist rates. However, the imperfection of practical FIR filter and the correlation based detection mode give rise to two kinds of spurious peaks in power spectrum estimation, that greatly limit the application of coprime DFTFB. Through detailed analysis of the spurious peaks, this paper proposes a modified spectral analyzer based on dual coprime DFTFBs and sub-decimation, which not only depresses the spurious peaks, but also improves the frequency estimation accuracy. The mathematical principle proof of the proposed spectral analyzer is also provided. In discussion of simultaneous signals detection, an O-extended MN-band coprime DFTFB (OExt M-N coprime DFTFB) structure is naturally deduced, where M, N, and O are coprime with each other. The original MN-band coprime DFTFB (M-N coprime DFTFB) can be seen a special case of the OExt M-N coprime DFTFB with extending factor O equals ‘1’. In the numerical simulation section, BPSK signals with random carrier frequencies are employed to test the proposed spectral analyzer. The results of detection probability versus SNR curves through 1000 Monte Carlo experiments verify the effectiveness of the proposed spectrum analyzer.

  • Perceptual Distributed Compressive Video Sensing via Reweighted Sampling and Rate-Distortion Optimized Measurements Allocation

    Jin XU  Yan ZHANG  Zhizhong FU  Ning ZHOU  

     
    LETTER-Image Processing and Video Processing

      Pubricized:
    2017/01/06
      Vol:
    E100-D No:4
      Page(s):
    918-922

    Distributed compressive video sensing (DCVS) is a new paradigm for low-complexity video compression. To achieve the highest possible perceptual coding performance under the measurements budget constraint, we propose a perceptual optimized DCVS codec by jointly exploiting the reweighted sampling and rate-distortion optimized measurements allocation technologies. A visual saliency modulated just-noticeable distortion (VS-JND) profile is first developed based on the side information (SI) at the decoder side. Then the estimated correlation noise (CN) between each non-key frame and its SI is suppressed by the VS-JND. Subsequently, the suppressed CN is utilized to determine the weighting matrix for the reweighted sampling as well as to design a perceptual rate-distortion optimization model to calculate the optimal measurements allocation for each non-key frame. Experimental results indicate that the proposed DCVS codec outperforms the other existing DCVS codecs in term of both the objective and subjective performance.