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The Journal of china Universities of posts and telecommunications 2009年第2期16卷 1-7页

作者： wang jian yang xun li dao-ben school of information engineering,beijing university of posts and telecommunications,beijing 100876,china school of information engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This article proposes a time/frequency synchronization algorithm in the multiple input multiple output （MIMO） systems, in which the perfect complete generalized complementary orthogonal loosely synchronous code groups are used as the synchronization sequence. The synchronization algorithm is divided into four stages： 1） synchronization in time domain by signal autocorrelation; 2） synchronization in frequency domain by fast Fourier transform （FFT）; 3） multipath dissociation using coherent detection and fine time synchronization; 4） fine frequency offset estimation by phase rotation. As per the perfect complete generalized complementary orthogonal loosely synchronous code groups, the cross-correlation and out-of-phase auto-correlation for any relative shift between any two codes is always zero. This ideal property makes the time/frequency synchronization algorithm simple and efficient. The simulation results show that even in the multipath fast fading channel with low signal noise ratio （SNR）, the MIMO system can get synchronized both in the time domain and frequency domain with high stability and reliability.

关键词： MIMO OFDM synchronization complementary orthogonal code loosely synchronous (LS) code

Performance of Gaussian waveform in OvTDM

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The Journal of china Universities of posts and telecommunications 2009年第1期16卷 32-37页

作者： yang xun wang jian li dao-ben Key Laboratory of information Processing and Intelligent Technology Beijing University of Posts and Telecommunications Beijing 100876 China

Waveforms play a key role in overlapping time division multiplexing （OvTDM） system. The OvTDM has been proved to be a novel transmission technique that can utilize time diversity to improve the bit error ratio （BER） performance in Rayleigh channel. According to the resulted law, the BER performance of Gaussian waveform in OvTDM also improves with the increase in the waveform parameter monotonically, and the rectangular waveform is the worst case of Gaussian waveform. In contrast, the spectrum effectiveness of Gaussian waveform OvTDM decreases with the increase in the waveform parameter. In the study, it is obtained that waveforms can achieve the best performance when the smallest correlation coefficient between neighbor symbols is e^-1 .

关键词： OvTDM inter symbol interference (ISI) Gaussian waveform rectangular waveforrn BER spectrum effectiveness

Course Group Development of Fundamental courses forElectronics and information Based on engineering Education

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Course Group Development of Fundamental courses forElectroni...

一种应用于协作MIMO-NOMA系统的符号检测算法

教育部中南地区高等学校电子电气基础课教学研究会第二十届学术年会

作者： Zu Yun-xiao,wang Wei-dong,Zhang jian-ming,liU li-hua,Ren Wei-zheng (school of Electronic engineering,beijing university of posts & telecommunications,beijing 100876,china)

During the college education the courses of fundamentals for every subject have a very important status in the knowledge framework of students’ *** study on contents and teaching methods and measures of the four fundamental courses for Electronics and information,which are ’Fundamentals of Circuit Analysis’,’Signals and Systems’,’Fundamentals of Electronic Circuits’,’Digital Circuit and Logic Design’,is introduced based on engineering education in this *** study on contents includes the optimization of courses’ contents,complementarity and strengthening between theory and experiment, combination of theory and engineering,and the hierarchical *** study on teaching methods and measures includes the change of teachers’ teaching notion and the training of the students’ ability in ideation, innovation,synthesis,induction,simulation and practice.

关键词： engineering education course group electronics and information professional fundamental courses

来源： cnki会议评论

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北京邮电大学学报 2024年第4期47卷 136-142页

作者：谢文武李攀肖健王骥杨亮湖南理工学院信息科学与工程学院岳阳414006 华中师范大学物理科学与技术学院武汉430079 湖南大学信息科学与工程学院长沙410082

受发射端的功率分配与叠加编码的影响,基于单任务神经网络的功率域非正交多址接入(NOMA)符号检测算法无法兼容不同用户的符号检测任务。针对用户辅助的协作多输入多输出(MIMO)-NOMA通信系统,设计基于多任务神经网络的符号检测算法,通过... 详细信息

受发射端的功率分配与叠加编码的影响,基于单任务神经网络的功率域非正交多址接入(NOMA)符号检测算法无法兼容不同用户的符号检测任务。针对用户辅助的协作多输入多输出(MIMO)-NOMA通信系统,设计基于多任务神经网络的符号检测算法,通过学习协作MIMO-NOMA系统中信号的深层共享特征,实现不同用户的联合符号检测。由于协作通信中不同用户接收信号的数据分布不同,并且存在数据孤岛问题,而机器学习模型要求训练数据和测试数据均独立采样于同一数据分布,因此提出多任务联邦学习框架来解决这一问题。实验结果表明,随着信噪比的提高,所提出的符号检测算法较传统符号检测算法展现出更好的性能。

关键词：协作非正交多址接入符号检测多任务联邦学习

Attention Matters: An Exploration of Relationship Between Google Search Behaviors and Crude Oil Prices

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Journal of Systems Science & Complexity 2019年第5期32卷 1438-1459页

作者： li Xin ZHANG xun wang Shouyang MA jian Donlinks school of Economics and Management University of Science and Technology BeijingBeijing 100083China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China school of Economics and Management University of Chinese Academy of SciencesBeijing 100190China Department of information Systems City University of Hong KongTat Chee AvenueKowloonHong KongChina.

Extant studies have suggested that Google search volume data can serve as a new and direct measure of investor attention in various research fields such as economy, financial and energy markets. However, it is not clear that whether investor attention influences prices in the same direction in different market states(prices increase or decrease). In this paper, the authors propose a measure of speculative attention, demonstrate its advantages by comparing it with several existing ones, and then adopt a Markov switching autoregressive model and an EGARCH model to examine its influences on crude oil prices in two market states. It is argued that the responses of crude oil prices to investor attention are asymmetrical in the two states of crude oil prices. The empirical study shows that one increase in searches causes a significant positive increase in crude oil prices during oil price surges, and a more significant reduction of prices during oil price collapses. The authors also conduct robustness checks by limiting the sample periods and using other measures, and the results support the asymmetric effect of web search behaviors on crude oil prices.

关键词： Asymmetric response crude oil prices Google search investor attention Markov switching autoregressive model

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模块化可重构三指灵巧手设计与抓取实验研究

应用基础与工程科学学报 2024年第4期32卷 1199-1210页

作者：张勤俭王鹏程魏建李海源李星帅北京信息科技大学机电工程学院北京100192 首都医科大学附属北京友谊医院北京100020 北京邮电大学智能工程与自动化学院北京100876

在服务和工业领域等非结构化环境中,因抓取对象、抓取部位、作业工艺等具备多样化、不确定等特点,灵巧地抓取物体是具有挑战性的.基于连杆传动机构,研制了一种新型的模块化可重构三指灵巧手.手指与手掌分别采用模块化设计,模块化手指的... 详细信息

在服务和工业领域等非结构化环境中,因抓取对象、抓取部位、作业工艺等具备多样化、不确定等特点,灵巧地抓取物体是具有挑战性的.基于连杆传动机构,研制了一种新型的模块化可重构三指灵巧手.手指与手掌分别采用模块化设计,模块化手指的两个关节均采用连杆传动,有效减小了手指体积,同时可以获得较大的指尖力,降低了制造维护的复杂性.可重构手掌可以变换模块化手指的空间位置,对不同抓取目标形成最优的抓取姿势.其具有以下特点:7个主动自由度,指尖力为25N,有效载荷为5kg,重量为1.55kg,体积小巧,具有力感知能力且易于集成.日常生活用品与工具的抓取实验验证了灵巧手的有效性和灵巧性.结果表明,模块化可重构三指灵巧手可以灵巧地抓取和操作日常生活用品和工具,可有效满足服务与工业领域中灵巧抓取的需求.

关键词：多指灵巧手模块化设计可重构连杆传动抓取实验

An Android Malware Detection System Based on Feature Fusion

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Chinese Journal of Electronics 2018年第6期27卷 1206-1213页

作者： li jian wang Zheng wang Tao TANG Jinghao yang Yuguang ZHOU Yihua school of Computer Science Beijing University of Posts and Telecommunications school of Computer Science Beijing University of Technology

In order to improve the detection efficiency of Android malicious application, an Android malware detection system based on feature fusion is proposed on three levels. Feature fusion especially emphasizes on ten categories, which combines static and dynamic features and includes 377 features for classification. In order to improve the accuracy of malware detection, attribute subset selection and principle component analysis are used to reduce the dimensionality of fusion features. Random forest is used for classification. In the experiment, the dataset includes 43,822 benign applications and 8,454 malicious applications. The method can achieve 99.4% detection accuracy and 0.6% false positive rate. The experimental results show that the detection method can improve the malware detection efficiency in Android platform.

关键词： Android security Malware detection Feature fusion Machine learning information security

Incomplete fingerprint recognition based on feature fusion and pattern entropy

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The Journal of china Universities of posts and telecommunications 2013年第3期20卷 121-128页

作者： ZHANG Jie JING Xiao-jun CHEN Na wang jian-li school of information and Communication engineering Beijing University of Posts and Telecommunications Key Laboratory of Trustworthy Distributed Computing and Service Ministry of Education Beijing University of Posts and Telecommunications

Considering the inherent characteristics of incomplete fingerprint： local feature loss and global information distortion, the recognition progress has been mainly restricted by two critical problems： how to precisely extract informative features and still with compact representation of the incomplete fingerprint; and how to effectively measure the similarity between fingerprint images. In this paper, to handle the first problem, both the minutiae and orientation field feature are extracted and then fused to get a more comprehensive feature with scale and rotation invariability. Dealing with the second one, the pattern entropy is introduced to robustly measure the similarity of two incomplete fingerprints. Extensive experiments have been conducted on both those popular fingerprint databases and our extended databases containing more incomplete fingerprints. Meanwhile, thorough performance comparisons have been made with existing approaches. Experimental results show that our approach has more efficient ability especially in incomplete fingerprint recognition, and also performs well in both accuracy and efficiency.

关键词： incomplete fingerprint recognition feature fusion pattern entropy similarity measurement

Attention shifting during child-robot interaction:a preliminary clinical study for children with autism spectrum disorder

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信息与电子工程前沿：英文版 2019年第3期20卷 374-387页

作者： Guo-bin WAN Fu-hao DENG Zi-jian jianG Sheng-zhao liN Cheng-lian ZHAO Bo-xun liU Gong CHEN Shen-hong CHEN Xiao-hong CAI Hao-bo wang li-ping li Ting YAN Jia-ming ZHANG Shenzhen Maternal&Child Healthcare Hospital Institute of Robotics and Intelligent Manufacturing The Chinese University of Hong Kong(Shenzhen) school of Mechanical engineering Zhejiang University Institute of information engineering&Technology Huaqiao University school of information and Control engineering China University of Mining and Technology school of Mechanical and Electrical engineering Beijing Information Science and Technology University Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences

There is an increasing need to introduce socially interactive robots as a means of assistance in autism spectrum disorder(ASD) treatment and rehabilitation, to improve the effectiveness of rehabilitation training and the diversification of treatment, and to alleviate the shortage of medical personnel in china's Mainland and other places in the world. In this preliminary clinical study, three different socially interactive robots with different appearances and functionalities were tested in therapy-like settings in four different rehabilitation facilities/institutions in Shenzhen, china. Seventy-four participants, including 52 children with ASD, whose processes of interacting with robots were recorded by three different cameras, all received a single-session three-robot intervention. Data were collected from not only the videos recorded, but also the questionnaires filled mostly by parents of the participants. Some insights from the preliminary results were obtained. These can contribute to the research on physical robo it design and evaluations on robots in therapy-like settings. First, when doing physical robot design, some preferential focus should be on aspects of appearances and functionalities. Second, attention analysis using algorithms such as estimation of the directions of gaze and head posture of a child in the video clips can be adopted to quantitatively measure the prosocial behaviors and actions(e.g., attention shifting from one particular robot to other robots) of the children. Third, observing and calculating the frequency of the time children spend on exploring/playing with the robots in the video clips can be adopted to qualitatively analyze such behaviors and actions. limitations of the present study are also presented.

关键词： Human-robot interaction Robot-enhanced therapy Socially interactive robots Robot-mediated intervention

WPANFIS:combine fuzzy neural network with multiresolution for network traffic prediction

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The Journal of china Universities of posts and telecommunications 2010年第4期17卷 88-93页

作者： li Rui CHEN jian-ya liU Yun-jie wang Zhen-kai school of information and Telecommunication engineering Beijing University of Posts and Telecommunications Beijing 100876 China china Unicorn Beijing 100140 China

A novel methodology for prediction of network traffic, WPANFIS, which relies on wavelet packet transform （WPT） for multi-resolution analysis and adaptive neuro-fuzzy inference system （ANFIS） is proposed in this article. The widespread existence of self-similarity in network traffic has been demonstrated in earlier studies, which exhibits both long range dependence （LRD） and short range dependence （SRD）. Also, it has been shown that wavelet decomposition is an effective tool for LRD decorrelation. The new method uses WPT as extension of wavelet transform which can decoorrelate LRD and make more precisely partition in the high-frequency section of the original traffic. Then ANFIS which can extract useful information from the original traffic is implemented in this study for better prediction performance of each decomposed non-stationary wavelet coefficients. Simulation results show that the proposed WPANFIS can achieve high prediction accuracy in real network traffic environment.

关键词： network traffic prediction WPT ANFIS