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Multi-channel blind deconvolution algorithm for multiple-input multiple-output DS/CDMA system

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Journal of Systems Engineering and Electronics 2007年第3期18卷 454-461页

作者： Cheng Hao guo wei Jiang Yi National Key Lab of Communication Univ. of Electronic Science and Technology Chengdu 610054 P. R. China

Direct sequence spread spectrum transmission can be realized at low SNR, and has low probabilityof detection. It is aly problem how to obtain the original users＇ signal in a non-cooperative context. In practicality, the DS/CDMA sources received are linear convolute mixing. A more complex multichannel blind deconvolution MBD algorithm is required to achieve better source separation. An improved MBD algorithm for separating linear convolved mixtures of signals in CDMA system is proposed. This algorithm is based on minimizing the average squared cross-output-channel-correlation. The mixture coefficients are totally unknown, while some knowledge about temporal model exists. Results show that the proposed algorithm can bring about the exactness and low computational complexity.

关键词： DS/CDMA signal non-cooperative MBD stochastic gradient algorithms for MBD.

股总动脉斑块稳定性联合颈动脉斑块最大厚度检测对老年急性脑梗死复发的预测价值

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陕西医学杂志 2025年第1期54卷 57-61页

作者：苗涛卫国赵清空军军医大学第一附属医院陕西西安710032 空军军医大学空军第九八六医院干部病房陕西西安710054

目的:探讨股总动脉斑块稳定性联合颈动脉斑块最大厚度对老年急性脑梗死复发的预测价值。方法:前瞻性选择256例老年急性脑梗死患者为研究对象,按照发病后1年内是否复发分为复发组和未复发组。收集所有患者基线资料与超声指标,采用非条件... 详细信息

目的:探讨股总动脉斑块稳定性联合颈动脉斑块最大厚度对老年急性脑梗死复发的预测价值。方法:前瞻性选择256例老年急性脑梗死患者为研究对象,按照发病后1年内是否复发分为复发组和未复发组。收集所有患者基线资料与超声指标,采用非条件二分类Logistic回归分析影响脑梗死复发的相关因素。绘制受试者工作特征(ROC)曲线分析此类超声指标对脑梗死复发的预测价值。结果:与非复发组比较,复发组糖尿病史、入院卒中量表(NIHSS)评分、收缩压、低密度脂蛋白胆固醇(LDL-C)、C反应蛋白、D-二聚体、股总动脉斑块易损评分、股总动脉颈动脉内中膜厚度(IMT)、颈动脉斑块最大厚度、颈动脉IMT均较高,差异有统计学意义(均P<0.05)。多因素Logistic回归分析显示,股总动脉斑块易损评分、颈动脉斑块最大厚度是影响老年急性脑梗死复发的独立危险因素(均P<0.05)。ROC分析显示,股总动脉斑块易损评分、颈动脉斑块最大厚度预测脑梗死复发的曲线下面积(AUC)分别为0.752,0.814,灵敏度分别为69.28%和77.80%;特异度分别为84.35%和82.82%,最佳诊断值分别为4.65分和2.78 mm。两者联合预测的AUC为0.903,明显高于前两者(均P<0.05)。结论:股总动脉斑块稳定性、颈动脉斑块最大厚度与老年急性脑梗死复发具有相关性,两者联合检测对脑梗死复发具有良好的预测价值,有助于脑梗死复发的高危人群进行鉴别和危险分层。

关键词：股总动脉斑块稳定性颈动脉斑块最大厚度脑梗死复发预测价值老年人

Improving SIMD Utilization with Thread-Lane Shuffled Compaction in GPGPU

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Chinese Journal of Electronics 2015年第4期24卷 684-688页

作者： LI Bingchao wei Jizeng guo wei SUN Jizhou School of Computer Science and Technology Tianjin University

GPGPUs adopt SIMT execution model in which each logical thread in a warp corresponds to a SIMD lane while can still follow an independent control *** a branch divergence appears and threads within a warp take different execution paths, GPGPUs have to execute each path serially through SIMD lane masking, which potentially decreases the SIMD utilization and performance. We propose an efficient thread compaction mechanism to handle branch divergence with a novel register file structure. We also develop a new thread scheduling policy cooperating with our compaction mechanism. The simulation results show that our approach improves the SIMD utilization up to 74.4% and achieves a maximum 11.1%performance speedup with small hardware overhead.

关键词： Graphics processing unit(GPU) Singleinstruction multiple-data(SIMD) Branch divergence Register file

Investigation on full distribution CNC system based on SERCOS bus

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Journal of Systems Engineering and Electronics 2008年第1期19卷 52-57页

作者： guo wei Chen zongyu Li Congxin National Die & Mould CAD Engineering Research Center Shanghai Jiaotong Univ. Shanghai 200030 P. R. China

A full distribution CNC system based on SERCOS bus is studied in accordance with the limitations of traditional PC-based motion card. The conventional PC-based motion control card is dispersed into several autonomous intelligent servo-control units with the function of servo driver. The autonomous intelligent servocontrol units realize the loop control of position, velocity and current. Interpolation computation is completed in PC and the computational results are transferred to every autonomous intelligent servo-control unit by high speed SERCOS bus. Software or hardware synchronization technology is used to ensure all servomotors are successive and synchronously running. The communication and synchronization technology of SERCOS are also researched and the autonomous intelligent servo-control card is developed byself. Finally, the experiment of circle contour process on a prototype system proves the feasibility.

关键词： offline interpolation full distribution CNC autonomous intelligent servo-control unit SERCOS bus communication and synchronization.

The Integration of CPS, CPSS, and ITS: A Focus on Data

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Tsinghua Science and Technology 2015年第4期20卷 327-335页

作者： wei guo Yi Zhang Li Li Department of Automation Tsinghua University Jiangsu Province Collaborative Innovation Center of Modern Urban Traffic Technologies

Cyber-Physical System （CPS） and Cyber-PhysicaI-Social System （CPSS） computing are now challenging existing research in many realms, including Intelligent Transportation Systems （ITS）. In this survey, we highlight some advances in the coevolution of CPS, CPSS, and ITS, with an emphasis on traffic data. We first explain the hierarchical architecture of CPS-ITS in terms of five layers： perception, communication, computing, control, and application. Then, we analyze the characteristics of traffic data in CPS-ITS, and enumerate some new technologies for data operation and management. Two typical cases of CPS-ITS, vehicular-communication-based traffic control systems and smart parking systems, are illustrated to describe how CPS is changing our lives and influencing the development of future ITS.

关键词： intelligent transportation systems Cyber-Physical System (CPS) Cyber-PhysicaI-Social System(CPSS) big data

Thrust and Torque Characteristics Based on a New cutter-head Load Model

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Chinese Journal of Mechanical Engineering 2015年第4期28卷 801-809页

作者： LIU Jianqin REN Jiabao guo wei Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University

Full face rock tunnel boring machine（TBM） has been widely used in hard rock tunnels, however, there are few published theory about cutter-head design, and the design criteria of cutter-head under complex geological is not clear yet. To deal with the complex relationship among geological parameters, cutter parameters, and operating parameters during tunneling processes, a cutter-head load model is established by using CSM（Colorado school of mines） prediction model. Force distribution on cutter-head under a certain geology is calculated with the new established load model, and result shows that inner cutters bear more force than outer cutters, combining with disc cutters abrasion; a general principle of disc cutters＇ layout design is proposed. Within the model, the relationship among rock uniaxial compressive strength（UCS）, penetration and thrust on cutter-head are analyzed, and the results shows that with increasing penetration, cutter thrust increases, but the growth rate slows and higher penetration makes lower special energy（SE）. Finally, a fitting mathematical model of ZT（ratio of cutter-head torque and thrust） and penetration is established, and verified by TB880 E, which can be used to direct how to set thrust and torque on cutter-head. When penetration is small, the cutter-head thrust is the main limiting factor in tunneling; when the penetration is large, cutter-head torque is the major limiting factor in tunneling. Based on the new cutter-head load model, thrust and torque characteristics of TBM further are researched and a new way for cutter-head layout design and TBM tunneling operations is proposed.

关键词： TBM(full face rock tunnel boring machine) cutter-head load model CSM(Colorado school of mines) model cutter-head layout design t

Nonlinear multifunctional sensor signal reconstruction based on least squares support vector machines and total least squares algorithm

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 497-503页

作者： Xin LIU guo wei Jin-wei SUN Dan LIU Department of Automatic Measurement and Control Harbin Institute of Technology Harbin 150001 China

Least squares support vector machines (LS-SVMs) are modified support vector machines (SVMs) that involve equality constraints and work with a least squares cost function, which simplifies the optimization procedure. In this paper, a novel training algorithm based on total least squares (TLS) for an LS-SVM is presented and applied to multifunctional sensor signal reconstruction. For three different nonlinearities of a multifunctional sensor model, the reconstruction accuracies of input signals are 0.001 36%, 0.031 84% and 0.504 80%, respectively. The experimental results demonstrate the higher reliability and accuracy of the proposed method for multifunctional sensor signal reconstruction than the original LS-SVM training algorithm, and verify the feasibility and stability of the proposed method.

关键词： Least squares support vector machine Total least squares Multifunctional sensor Signal reconstruction

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Chinese Journal of Electronics 2016年第4期25卷 608-613页

作者： guo Jiansheng LUO wei WANG Kun Zhengzhou Information Science and Technology Institute Unit 78179 of the PLA

By constructing three types of related-key differential characteristics,we present three corresponding related-key differential attacks on the *** the independence of the characteristics,we could recover 64 bits of the cipher’s master key with 2;chosen plain-texts,2;full-round DDP-64 encryptions and 2;bits of storage *** break the cipher,we only need to implement an exhaustive search for the rest 64 bits of the master key.

关键词： Block cipher DDP-64 block cipher Data dependent permutations(DDPs) Multiple related-key differential attacks

High-precision time domain reactive power measurement in the presence of interharmonics

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第4期12卷 330-337页

作者： Bei ZHANG guo wei Jin-wei SUN Department of Electrical and Computer Engineering Auburn University Auburn 36830 USA School of Electrical Engineering andAutomatton Harbin Institute of Technology Harbin 150001 China

When interharmonics exist in power system signals,large errors emerge in traditional time domain reactive power *** this paper,we present a novel time domain integral method with good effect of restraining interharmonics,synchronization error,and white noise,as well as the principle of the selection of the sampling periods when employing this *** current signal and phase-shifted voltage signal are reconstructed after the harmonic components of signals are extracted,so that the interharmonics are *** influence of the synchronization error on the measurement is reduced through removing the weight coefficients of the reactive *** the simulation,we apply several cosine windows to the proposed method and analyze signals containing both harmonics and *** results show that,in the presence of interharmonics,synchronization error,and white noise (with a fundamental signal-to-noise ratio of 40 dB) all together,the relative errors are within the magnitude of 10 4,which perfectly satisfies the practical requirement.

关键词： Cosine window Interharmonics Reactive power Synchronization error Windowed discrete Hilbert transform