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Chinese Physics B 2013年第2期22卷 559-564页

作者：伊国胜王江邓斌魏熙乐韩春晓 school of electrical and Automation engineering Tianjin University Tianjin Key Laboratory of Information Sensing & Intelligent Control Tianjin University of Technology and Education

To investigate whether and how manual acupuncture（MA） modulates brain activities,we design an experiment where acupuncture at acupoint ST36 of the right leg is used to obtain electroencephalograph（EEG） signals in healthy *** adopt the autoregressive（AR） Burg method to estimate the power spectrum of EEG signals and analyze the relative powers in delta（0 Hz-4 Hz）,theta（4 Hz-8 Hz）,alpha（8 Hz-13 Hz）,and beta（13 Hz-30 Hz） *** results show that MA at ST36 can significantly increase the EEG slow wave relative power（delta band） and reduce the fast wave relative powers（alpha and beta bands）,while there are no statistical differences in theta band relative power between different acupuncture *** order to quantify the ratio of slow to fast wave EEG activity,we compute the power ratio *** is found that the MA can significantly increase the power ratio index,especially in frontal and central *** the results highlight the modulation of brain activities with MA and may provide potential help for the clinical use of *** proposed quantitative method of acupuncture signals may be further used to make MA more standardized.

关键词： manual acupuncture electroencephalograph autoregressive Burg method relative power

Coal–rock interface detection on the basis of image texture features

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International Journal of Mining Science and Technology 2013年第5期23卷 681-687页

作者： Sun Jiping Su Bo school of Mechanical Electronic & Information engineering China University of Mining & Technology College of electrical engineering and Automation Henan Polytechnic University

Based on the stability and inequality of texture features between coal and rock,this study used the digital image analysis technique to propose a coal–rock interface detection *** using gray level co-occurrence matrix,twenty-two texture features were extracted from the images of coal and *** dimension of the feature space reduced to four by feature selection,which was according to a separability criterion based on inter-class mean difference and within-class *** experimental results show that the optimized features were effective in improving the separability of the samples and reducing the time complexity of the *** the optimized low-dimensional feature space,the coal–rock classifer was set up using the fsher discriminant *** the 10-fold cross-validation technique,the performance of the classifer was evaluated,and an average recognition rate of 94.12%was *** results of comparative experiments show that the identifcation performance of the proposed method was superior to the texture description method based on gray histogram and gradient histogram.

关键词： Coal–rock interface detection Texture Gray level co-occurrence matrix Feature selection Fisher discriminant method Cross-validation

A multi-task deep learning model for short-term taxi demand forecasting considering spatiotemporal dependences

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Journal of Traffic and Transportation engineering(English Edition) 2021年第1期8卷 83-94页

作者： Huimin Luo Jianming Cai Kunpeng Zhang Ruihang Xie Liang Zheng school of Traffic and Transportation engineering Central South UniversityChangsha 410075China College of electrical engineering Henan University of TechnologyZhengzhou 450001China

Short-term taxi demand forecasting is of great importance to incentivize vacant cars moving from over-supply regions to over-demand regions,which can minimize the wait time for passengers and *** the consideration of spatiotemporal dependences,this study proposes a multi-task deep learning(MTDL)model to predict short-term taxi demand in multi-zone *** nonlinear Granger causality test is applied to explore the causality relationships among various traffic zones,and long short-term memory(LSTM)is used as the core neural unit to construct the framework of the multi-task deep learning *** addition,several hyperparameter optimization methods(e.g.,grid search,random search,Bayesian optimization,hyperopt)are used to tune the *** the taxi trip data in New York City for validation,the multi-task deep learning model considering spatiotemporal dependences(MTDL*)is compared with the single-task deep learning model(STDL),the full-connected multi-task deep learning model(MTDL#)and other benchmark algorithms(such as LSTM,support vector machine(SVM)and k-nearest neighbors(k-NN)).The experiment results show that the proposed MTDL model is promising to predict short-term taxi demand in multi-zone level,the nonlinear Granger causality analysis is able to capture the spatiotemporal correlations among various traffic zones,and the Bayesian optimization is superior to the other three methods,which verified the feasibility and adaptability of the proposed method.

关键词： Traffic engineering Short-term traffic prediction Deep learning Multi-task model Spatiotemporal dependences

A Survey and Taxonomy of Resource Allocation Methods in Wireless Networks

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Journal of Communications and Information Networks 2021年第4期6卷 372-384页

作者： Hui Liang Wei Zhang school of electrical engineering and Intelligentization Dong-guan University of TechnologyDongguan 523808China Peng Cheng Laboratory Shenzhen 518055China school of electrical engineering and Telecommunications the University of New South WalesSydneyNSW 2052Australia

Resource allocation is a fundamental and vital issue for arbitrary wireless networks,which can guarantee the network to run efficiently and ***,in the 5G and future 6G networks,numerous distinct wireless network service demands will be requested from various vertical *** to select the most suitable one from these countless methods accurately and efficiently is still a far unsolved *** this survey,we give a comprehensive review of the domain of resource allocation in wireless *** survey begins with an overview of the resource allocation problem in present wireless networks and related works about the review of resource allocation *** then give a novel unified framework by using a six-tuple model for existing resource allocation methods of wireless *** to this model,we categorize these methods into two main classifications,namely single decision maker and multiple decision maker resource *** discussion and representative research results about the above taxonomy are subsequently ***,the conclusion and some promising research opportunities are presented at the end of the survey paper.

关键词： resource allocation optimization theory game theory wireless networks

Effect of Preparation Methods on Mechanical Properties of PVA/HA Composite Hydrogel

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Journal of Bionic engineering 2010年第3期7卷 235-243页

作者： Dekun Zhang~1, Junjie Duan~1, Dagang Wang~2, Shirong Ge~2 1. school of Materials Science and engineering, China University of Mining and Technology Xuzhou 221116, P. R. China 2. school of Mechanical and electrical engineering, China University of Mining and Technology, Xuzhou 221116, P. R. China school of Materials Science and engineering China University of Mining and Technology Xuzhou P. R. China school of Mechanical and electrical engineering China University of Mining and Technology Xuzhou P. R. China

Poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) composite hydrogel specimens were prepared with 15% PVA and 1%,2%, 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical properties were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical properties of PVA/HA compositehydrogel. The results of static mechanical tests showed that the PVA/HA composite hydrogel with 3% HA and ninefreezing-thawing cycles had excellent stress relaxation properties, higher relaxation ratio, lower stress equilibrium value andpresented better properties of creep and recovery. The results of dynamic mechanical test showed that the PVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus, so was the PVA/HA compositehydrogel with 3% HA.

关键词： composite hydrogel HA contents freezing-thawing cycles static properties dynamic properties

Performance Analysis and Comparison of Two Fault-Tolerant Model Predictive Control Methods for Five-Phase PMSM Drives

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CES Transactions on electrical Machines and Systems 2021年第4期5卷 311-320页

作者： Wentao Huang Wei Hua Qigao Fan the school of Internet of Things engineering Jiangnan UniversityWuxi214122China the school of electrical engineering Southeast UniversityNanjing 210096China

Model predictive current control(MPCC)and model predictive torque control(MPTC)are two derivatives of model predictive *** two control methods have demonstrated their strengths in the fault-tolerant control of multiphase motor *** explore the inherent link,the pros and cons of two strategies,the performance analysis and comparative investigation of MPCC and MPTC are conducted through a five-phase permanent magnet synchronous motor with open-phase *** MPCC,the currents of fundamental and harmonic subspaces are simultaneously employed and constrained for a combined regulation of the open-circuit fault *** MPTC,apart from the torque and the stator flux related to fundamental subspace,the x-y currents are also considered and predicted to achieve the control of harmonic *** principles of two methods are demonstrated in detail and the link is explored in terms of the cost ***,the performance by two methods is experimentally assessed in terms of steady-state,transition,and dynamic ***,the advantages and disadvantages of each method are concluded.

关键词： Permanent magnet motor five-phase fault-tolerant control model predictive control

APU-D* Lite: Attack Planning under Uncertainty Based on D* Lite

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Computers, Materials & Continua 2020年第11期65卷 1795-1807页

作者： Tairan Hu Tianyang Zhou Yichao Zang Qingxian Wang Hang Li State Key Laboratory of Mathematical engineering and Advanced Computing Zhengzhou450001China school of electrical engineering and Telecommunications UNSW KensingtonNSW 2033Australia

With serious cybersecurity situations and frequent network attacks,the demands for automated pentests continue to increase,and the key issue lies in attack *** the limited viewpoint of the attacker,attack planning under uncertainty is more suitable and practical for pentesting than is the traditional planning approach,but it also poses some *** address the efficiency problem in uncertainty planning,we propose the APU-D*Lite algorithm in this ***,the pentest framework is mapped to the planning problem with the Planning Domain Definition Language(PDDL).Next,we develop the pentest information graph to organize network information and assess relevant exploitation actions,which helps to simplify the problem ***,the APU-D*Lite algorithm is introduced based on the idea of incremental heuristic *** method plans for both hosts and actions,which meets the requirements of *** the pentest information graph as the input,the output is an alternating host and action *** experiments,we use the attack success rate to represent the uncertainty level of the *** result shows that APU-D*Lite displays better reliability and efficiency than classical planning algorithms at different attack success rates.

关键词： Attack planning under uncertainty automated pentest APU-D*Lite algorithm incremental heuristic search

Linear Precoder Design for Correlated Rician Fading Channel Under Imperfect CSI

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中国通信:英文版 2023年第9期20卷 160-170页

作者： S.B.M.Priya school of electrical and Electronics engineering SASTRA Deemed UniversityThanjavur 613401India

In this paper,we have modeled a linear precoder for indoor multiuser multiple input multiple output(MU-MIMO)system with imperfect channel state information(CSI)at *** Rician channel is presumed to be mutually coupled and spatially,temporarily *** imperfection with CSI is primarily due to the channel estimation error at receiver and feedback delay amidst the receiver and transmitter in CSI *** with,the insufficient spacing between the antenna at transmitter and receiver persuades mutual coupling(MC)among the array *** addition,the MIMO channel is presumed to be jointly correlated(Weichselberger correlation model).When we look back on the existing precoder design,it considered spatial correlation alone disregarding joint correlation of antenna array *** all above assumption,we have designed a linear precoder which minimizes mean squared error(MSE)subjected to total transmit power constraint for MUMIMO *** simulation results proven that proposed precoder shows substantial enhancement in bit error rate(BER)performance in comparison with the existing *** mathematical analysis corroborates the simulation results.

关键词： channel estimation error feedback delay MMSE linear precoder mutual coupling spatial cor-relation Weichselberger correlation model

Fibroblast proliferation alters cardiac excitation conduction and contraction： a computational study

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2014年第3期15卷 225-242页

作者： He-qing ZHAN Ling XI Guo-fa SHOU Yun-liang ZANG Feng LIU Stuart CROZIER Department of Biomedical engineering Zhejiang University Hangzhou 310027 China school of Information Technology and electrical engineering the University of Queensland Brisbane QLD 4072 Australia

In this study, the effects of cardiac fibroblast proliferation on cardiac electric excitation conduction and mechanical contraction were investigated using a proposed integrated myocardial-fibroblastic electromechanical model. At the cellular level, models of the human ventricular myocyte and fibroblast were modified to incorporate a model of cardiac mechanical contraction and cooperativity mechanisms. Cellular electromechanical coupling was realized with a calcium buffer. At the tissue level, electrical excitation conduction was coupled to an elastic mechanics model in which the finite difference method （FDM） was used to solve electrical excitation equations, and the finite element method （FEM） was used to solve mechanics equations. The electromechanical properties of the proposed integrated model were investigated in one or two dimensions under normal and ischemic pathological conditions. Fibroblast proliferation slowed wave propagation, induced a conduction block, decreased strains in the fibroblast proliferous tissue, and increased dispersions in depolarization, repolarization, and action potential duration （APD）. It also distorted the wave-front, leading to the initiation and maintenance of re-entry, and resulted in a sustained contrac- tion in the proliferous areas. This study demonstrated the important role that fibroblast proliferation plays in modulating cardiac electromechanical behaviour and which should be considered in planning future heart-modeling studies.

关键词： Cardiac model Electromechanics Fibroblast proliferation

Study on wave dispersion characteristics of piezoelectric sandwich nanoplates considering surface effects

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Applied Mathematics and Mechanics(English Edition) 2022年第9期43卷 1339-1354页

作者： Biao HU Juan LIU Yuxing WANG Bo ZHANG Jing WANG Huoming SHEN Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China school of Mechanical and electrical engineering Southwest Petroleum UniversityChengdu 610500China

In this study,the wave propagation properties of piezoelectric sandwich nanoplates deposited on an orthotropic viscoelastic foundation are analyzed by considering the surface effects(SEs).The nanoplates are composed of a composite layer reinforced by graphene and two piezoelectric surface *** the modified Halpin-Tsai model,the material parameters of composite layers are *** displacement field is determined by the sinusoidal shear deformation theory(SSDT).The Euler-Lagrange equation is derived by employing Hamilton’s principle and the constitutive equations of piezoelectric layers considering the ***,the nonlocal strain gradient theory(NSGT)is used to obtain the equations of ***,the effects of scale parameters,graphene distribution,orthotropic viscoelastic foundation,and SEs on the propagation behavior are numerically *** results reveal that the wave frequency is a periodic function of the orthotropic ***,the wave frequency increases with the increase in the SEs.

关键词： surface effect(SE) scale parameters orthotropic foundation functional gradient graphene piezoelectric sandwich nanoplate