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Robust fuzzy sliding-mode control for T-S model based permanent magnet synchronous motor

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中南大学学报（自然科学版） 2009年第S1期40卷 68-73页

作者：张细政王耀南 school of Computer and communication Hunan Institute of Engineering school of Electrical and information engineering Hunan University

A fuzzy sliding-mode control (FSMC) scheme based on T-S fuzzy models was proposed for the permanent magnet synchronous motor (PMSM) drive system to solve the speed tracking problem. A T-S fuzzy model was firstly formed to represent the nonlinear system of PMSM. For converting the tracking control into a stabilization problem, a new control design was proposed to define the internal desired states. Then, the FSMC controller for PMSM system with parameter variation and load disturbance was designed based on the fuzzy model. The performance of the proposed controller was verified by experimental results on PMSM system. The results show that the FSMC scheme can drive the dynamics of PMSM into a designated sliding surface in finite time and guarantee the property of asymptotical stability. The information of upper bound of modeling errors as well as perturbations is not required when using the FSMC controller.

关键词： permanent magnet synchronous motor (PMSM) uncertain T-S nonlinear systems sliding-mode control fuzzy sliding surfaces linear matrix inequalities (LMIs)

NIR Chemical-Image Analysis Based on Adaptive Local Optimization PSO

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Chinese Journal of Electronics 2014年第1期23卷 115-118页

作者： YANG Xiukun ZHONG Mingliang JING Xiaojun WANG Jianli CHEN Xuqi College of information and communication engineering Harbin Engineering University school of information and communication engineering Beijing University of Posts and Telecommunication

Principal component analysis(PCA) combined with cluster analysis has become an effective approach for Near-infrared(NIR) chemical image *** cluster algorithms are sensitive to initial starting conditions and can be trapped into local optimal solutions. To overcome the drawbacks, we develop a new algorithm in this paper which improves Particle swarm optimization with Adaptive local optimization(ALO-PSO).Simulation experiments performed on NIR image of tablet verify the feasibility and effectiveness of the proposed algorithm. Experimental results of the clustering performances indicate that ALO-PSO algorithm offers an alternative approach for solving data clustering problems in NIR chemical image analysis.

关键词： Near-infrared chemical image Principal component analysis Cluster analysis Particle swarm optimization(PSO) Adaptive local optimization(ALO)

Efficient and secure outsourcing of bilinear pairings with single server

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Science China(information Sciences) 2018年第3期61卷 240-242页

作者： Min DONG Yanli REN school of communication and information engineering Shanghai University

Dear editor,Cloud computing is playing important role at the era of big data,and its availability makes outsourcing computations possible[1].By outsourcing computations,mobile devices with weak computational ability can outsource complex operations to powerful cloud servers so that the time cost can be greatly reduced[2].Despite of unique advantages,there are also some security challenges we need pay attention to.

关键词： Efficient and secure outsourcing of bilinear pairings with single server

Self-Interference Elimination by Physical Feedback Channel in CCFD for 3-D Beamforming communication

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China communications 2017年第9期14卷 62-71页

作者： Naveed Ali Kaimkhani Zhe Chen Fuliang Yin school of information and communication engineering Dalian University of Technology

The 3-D beamforming scheme has elite as evolving interest because of its efficiency to empower assorted techniques such as vertical and horizontal domains and emanation beamforming according to subscriber's provisions. Usually, 3-D beamforming communication is set up on FDD/TDD approach those effects on the performance of spectrum and energy efficiency. Co-frequency and CoTime Full Duplex(CCFD) is an effective solution to improve the spectrum and energy efficiency by transmitting and receiving simultaneously in frequency and time domain. While, CCFD communication often face the self-interference issue when communication occurs, simultaneously. Consequently, in this paper a self-interference elimination by physical feedback channel in CCFD for 3-D Beamforming communication scheme is proposed to improve the over-all system performance in terms of energy and spectrum efficiency. The simulation and analytical outcomes demonstrated that the proposed system is superior than the traditional one.

关键词： spectrum efficiency energy effi-ciency co-frequency and co-time full duplex self-interference suppression 3-D beamform-ing

A novel active-passive protection strategy endows carbonyl iron with excellent intelligent anti-corrosion and microwave absorption dual functional characteristics

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Nano Research 2025年第1期18卷 487-500页

作者： Wei Tian Quanyuan Feng Linbo Zhang Yinfan Liu Xian Jian Longjiang Deng Institute of Microelectronics School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 611756China National engineering Researching Centre of Electromagnetic Radiation Control Materials Key Laboratory of Multi-Spectral Absorbing Materials and Structures of Ministry of EducationState Key Laboratory of Electronic Thin Films and Integrated DevicesSchool of Electronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu 611731China school of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China The Yangtze Delta Region Institute(Huzhou)&school of Electronic Science and engineering University of Electronic Science and Technology of ChinaHuzhou 313001China

Carbonyl iron absorbers(CI)face significant challenges in practical applications,such as corrosion,interface bonding failure,detachment,and high maintenance ***,we have developed intelligent self-healing technology based on proactive/passive mechanisms via in situ synthesis of self-healing factors(polydopamine/benzotriazole(PDA/BTA))and physical barrier layers(SiO_(2)/1,1,1,3,3,3-hexamethyl disilazane,SiO_(2)/HMDS)to enhance corrosion resistance,while also being compatible with efficient microwave absorption *** unique multiscale structure gives full play to the utilization of the roles of each functional layer,including the intelligent self-healing features of PDA/BTA,physical shielding and spatial confinement characteristics of SiO_(2)/HMDS,and magnetic-dielectric synergistic mechanism resulted from the good impedance matching characteristics,the conduction loss,the interfacial polarization loss and natural *** asfabricated composites achieved an exceptional minimum reflection loss value of-55.4 dB at 10.7 GHz and the effective absorption band of 7.6 ***,it still exhibits obvious self-healing and corrosion resistance characteristics after 360 h corrosion treatment,ascribed to the self-healing mechanism of PDA/BTA and the blocking intervention effect of SiO_(2)/*** work is considered to pave the way for the synthesis of high-performance magnetic absorbers,especially in enhancing their intelligent self-healing ability in corrosive environments.

关键词： microwave absorption intelligent self-healing technology carbonyl iron multiscale structure magneticdielectric synergistic mechanism

Collaborative beamforming based on directional perturbation using one bit feedback

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Journal of Systems engineering and Electronics 2016年第3期27卷 549-554页

作者： Haifen Yang Ning Ding Zhi Zheng Shuisheng Lin Zhongpei Zhang Guangjun Li school of communication & information engineering University of Electronic Science and Technology of China

A novel collaborative beamforming algorithm is proposed in a wireless communication system with multiple transmitters and one receiver. All transmitters take part in the collaboration and the weighted message is transmitted simultaneously. In order to maximize the beamforming gain, the transmitters use one bit feedback information to adjust the phase offset. It tracks the direction in which the signal strength at the receiver can increase. The directional search and perturbation theory is used to achieve the phase alignment. The feasibility of the proposed algorithm is proved both experimentally and theoretically. Simulation results show that the proposed algorithm can improve the convergent speed of the phase alignment.

关键词： collaborative beamforming one-bit feedback directional perturbation convergent speed

Capacity and Spatial Correlation Measurements of Compact MIMO Antennas

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China communications 2021年第6期18卷 137-145页

作者： Dazhi Piao Meng Wang Jie Zuo Hao Zhou school of information and communication engineering Communication University of ChinaBeijing 100024China

The dual-port compact multiple-input multiple-output(MIMO)dipole antennas with close spacing d of 0.5λand 0.3λare designed,and some electromagnetic band gap(EBG)structures are inserted between them to reduce mutual *** MIMO antennas with d=0.5λand 0.3λ,and with different mutual couplings are fabricated and measured,the channel capacity and correlation coefficient(CC)are analyzed and compared in a rich multipath reverberation chamber(RC),an office and a conference *** show that if d is reduced from 0.5λto 0.3λ,in the RCs,channel capacities of all the antennas are very close to that of the *** channel,although the average CCs are increased from 0.168 in the nonlossy RC to 0.269 in the lossy *** the office and conference rooms,compared with the RC,the average capacities of those antennas get a slight reduction,however,in most cases,the capacity of d=0.5λis larger than that of d=0.3λ,and the antennas with EBG have a larger capacity compared with the antennas without EBG,with a corresponding reduction of CC.A non-line-of-sight(NLOS)scenario of through-the-wall is also investigated.

关键词： compact MIMO antenna channel capacity spatial correlation measurement

Radio map updated method based on subscriber locations in indoor WLAN localization

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Journal of Systems engineering and Electronics 2015年第6期26卷 1202-1209页

作者： Ying Xia Zhongzhao Zhang Lin Ma school of Electronics and information engineering Harbin Institute of Technology school of communication and Electronic engineering Qiqihar University

With the rapid development of wireless local area network （WLAN） technology, an important target of indoor positioning systems is to improve the positioning accuracy while reducing the online calibration effort to overcome signal time-varying. A novel fingerprint positioning algorithm, known as the adaptive radio map with updated method based on hidden Markov model （HMM）, is proposed. It is shown that by using a collection of user traces that can be cheaply obtained, the proposed algorithm can take advantage of these data to update the labeled calibration data to further improve the position estimation accuracy. This algorithm is a combination of machine learning, information gain theory and fingerprinting. By collecting data and testing the algorithm in a realistic indoor WLAN environment, the experiment results indicate that, compared with the widely used K nearest neighbor algorithm, the proposed algorithm can improve the positioning accuracy while greatly reduce the calibration effort.

关键词： subscriber location wireless local area network(WLAN) positioning accuracy calibration effort hidden Markovmodel (HMM).

Performance analysis for MU-MIMO enabled LTE-U networks coexisting with D2D and WiFi network

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Digital communications and Networks 2024年第5期10卷 1289-1296页

作者： Errong Pei Chenkai Ren Wei Li Qimei Chen Bingguang Deng Jiarui Song school of communication and information engineering Chongqing University of Posts and Telecommunications Chongqing Jinmei communication Co. Ltd Electronic information school Wuhan University

LTE-Unlicensed(LTE-U) network is a type of cellular communication network operating the unlicensed *** cellular traffic to WiFi or Device-to-Device(D2D) network can lead to interference among *** Multiple-Input Multiple-Output(MIMO) technology in Cellular Base Station(CBS) and WiFi Access Point(WAP) can effectively reduce interference among D2D,WiFi and cellular *** our best knowledge,there is still no literature to explicitly study the characteristics of the traffic offloading in the Multiple-User MIMO(MU-MIMO) enabled network coexisting with D2D and WiFi *** this article,we thoroughly investigate the impact of D2D communication and MU-MIMO enabled WAP and CBS on the performance of the LTE-U *** specifically,we derive the expressions of the downlink rates for cellular users,D2D users,and WiFi users with incomplete Channel State information(CSI) feedback,and we validate our analysis through Monte-Carlo *** results illustrate the following conclusions.(ⅰ) Increasing the number of WiFi users,the length of CSI feedback,and the quantity of D2D pairs that reuse the channel with a single cellular user can increase the total throughput of the heterogeneous network.(ⅱ) The total throughput decreases when more than two users are offloaded to D2D pairs,and increases as the number of offloaded users increases when less than six users are offloaded to WiFi network.(ⅲ) Simultaneously offloading traffic to D2D pairs and WiFi network can obtain higher total throughput than offloading traffic to only one of them.

关键词： LTE-unlicensed WiFi AP MU-MIMO D2D