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High precise control method for a new type of Piezoelectric electro-hydraulic servo valve

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Journal of Central South university of Technology 2007年第6期14卷 832-837页

作者：周淼磊田彦涛高巍杨志刚 college of communication Engineering Jilin University college of Machinery Science and Engineering Jilin University

A new type of piezoelectric electro-hydraulic servo valve system was proposed. And then multilayer piezoelectric actuator based on new piezoelectric ceramic material was used as the electricity-machine converter of the proposed piezoelectric electro-hydraulic servo valve. The proposed piezoelectric electro-hydraulic servo valve has ascendant performance compared with conventional ones. But the system is of high nonlinearity and uncertainty, it cannot achieve favorable control performance by conventional control method. To develop an efficient way to control piezoelectric electro-hydraulic servo valve system, a high-precise fuzzy control method with hysteresis nonlinear model in feedforward loop was proposed. The control method is separated into two parts: a feedforward loop with Preisach hysteresis nonlinear model and a feedback loop with high-precise fuzzy control. Experimental results show that the hysteresis loop and the maximum output hysteresis by the PID control method are 4.22% and 2.11 μm, respectively; the hysteresis loop and the maximum output hysteresis by the proposed control method respectively are 0.74% and 0.37 μm, respectively; the maximum tracking error by the PID control method for sine wave reference signal is about 5.02%, the maximum tracking error by the proposed control method for sine wave reference signal is about 0.85%.

关键词： piezoelectric electro-hydraulic servo valve hysteresis nonlinearity Preisach model fuzzy control

Investigation on random access in a VLC system with multipacket reception in the presence of hidden devices and obstructions

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Optoelectronics Letters 2016年第6期12卷 455-460页

作者：蔡文静迟学芬赵琳琳 college of communication Engineering Jilin University

Due to the directionality of light, the hidden device problem and the obstruction cannot be ignored for carrier sense multiple access with collision avoidance(CSMA/CA)-based uplink visible light communication(VLC). In this paper, we introduce multipacket reception(MPR) to handle the hidden device problem in VLC system. We model the traffic of the device with on/off Markov source. With the unsaturated traffic, we formulate a two dimensional(2D) Markov chain to model the CSMA/CA-based slotted random access procedure to evaluate the effects of hidden devices and obstructions on the performance of MPR-aided VLC system, which are mapped into the transition probabilities of the Markov chain. Then, we analyze the throughput and the reception power efficiency(RE) of MPR-aided VLC system with the obstructed optical channel. Numerical results show that the effect is negative when hidden devices or obstructions appear solely. But when they appear simultaneously, they will interact with each other to mitigate the negative effects.

关键词： hidden CSMA throughput collision obstruction interact solely traffic handle aided

Membrane-inspired quantum bee colony optimization and its applications for decision engine

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Journal of Central South university 2014年第5期21卷 1887-1897页

作者：高洪元李晨琬 college of Information and communication Engineering Harbin Engineering University

In order to effectively solve combinatorial optimization problems,a membrane-inspired quantum bee colony optimization(MQBCO)is proposed for scientific computing and engineering *** proposed MQBCO algorithm applies the membrane computing theory to quantum bee colony optimization(QBCO),which is an effective discrete optimization *** global convergence performance of MQBCO is proved by Markov theory,and the validity of MQBCO is verified by testing the classical benchmark *** the proposed MQBCO algorithm is used to solve decision engine problems of cognitive radio *** hybridizing the QBCO and membrane computing theory,the quantum state and observation state of the quantum bees can be well evolved within the membrane *** results for cognitive radio system show that the proposed decision engine method is superior to the traditional intelligent decision engine algorithms in terms of convergence,precision and *** experiments under different communication scenarios illustrate that the balance between three objective functions and the adapted parameter configuration is consistent with the weights of three normalized objective functions.

关键词： quantum bee colony optimization membrane computing P system decision engine cognitive radio benchmarkfunction

Wideband Signal Detection Based on MWC Discrete Compressed Sampling Structure

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Transactions of Nanjing university of Aeronautics and Astronautics 2017年第2期34卷 105-114页

作者： Chen Tao Liu Lizhi Guo Limin college of Information and communication Engineering Harbin Engineering University

In order to solve the cross-channel signal problem caused by the uniform channelized wideband digital receiver when processing wideband signal and the problem that the sensitivity of the system greatly decreases when the bandwidth of wideband digital receiver increases,which both decrease the wideband radar signal detection performance,a new wideband digital receiver based on the modulated wideband converter(MWC)discrete compressed sampling structure and an energy detection method based on the new receiver are ***,the proposed receiver utilizes periodic pseudo-random sequences to mix wideband signals with baseband and other *** the mixed signals are low-pass filtered and downsampled to obtain the baseband compressed sampling data,which can increase the sensitivity of the ***,the cross-channel signal will all appear in any subbands,so the cross-channel signal problem can be solved easily by processing the baseband compressed sampling ***,we establish the signal detection model and formulate the criterion of the energy detection *** we directly utilize the baseband compressed sampling data to carry out signal detection without signal reconstruction,which decreases the complexity of the algorithm and reduces the computational ***,simulation experiments demonstrate the effectiveness of the proposed receiver and show that the proposed signal detection method is effective in low signal-to-noise ratio(SNR)compared with the conventional energy detection and the probability of detection increases significantly when SNR increases.

关键词： wideband digital receiver cross-channel signal modulated wideband converter(MWC) compressed sampling energy detection

High Frequency communication Network with Diversity: System Structure and Key Enabling Techniques

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China communications 2018年第9期15卷 46-59页

作者： Kun Xu Bin Jiang Zeyou Su Shengqing Wang Makun Guo Xiao Li Zhiyong Du college of Information and communication National University of Defense Technology

High frequency sky wave communication suffers from poor performance including poor link quality and low link success rate. To enhance performance, diversity technology is proposed in the high frequency communication network(HFCN) in this ***, we present the benefits and the challenges by introducing diversity technology into the existing HFCN. Secondly, to exploit the benefits fully and overcome the challenges, we propose a system structure suitable for deploying diversity technology in HFCN in large scale,based on the cloud radio access network and software defined network. Moreover, we present a general structure for the real-time updating frequency management system that plays a more important role especially when resource consuming(e.g., frequency) diversity technology is deployed. Thirdly, we investigate the key techniques enabling diversity technology deployment. Finally, we point out the future research directions to help the HFCN with diversity work more efficiently and intelligently.

关键词： high frequency high frequency communication network diversity technology access layer and core layer frequency management system

Learning Association Rules and Tracking the Changing Concepts on Webpages:An Effective Pornographic Websites Filtering Approach

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Journal of Electronic Science and Technology 2018年第1期16卷 24-36页

作者： Jyh-Jian Sheu college of communication National Chengchi UniversityTaipei 11605

We applied the decision tree algorithm to learn association rules between webpage’s category(pornographic or normal) and the critical *** on these rules, we proposed an efficient method of filtering pornographic webpages with the following major advantages: 1) a weighted window-based technique was proposed to estimate for the condition of concept drift for the keywords found recently in pornographic webpages; 2) checking only contexts of webpages without scanning pictures; 3) an incremental learning mechanism was designed to incrementally update the pornographic keyword database.

关键词： Concept drift data mining decision tree pornographic websites filtering

A low voltage and small hysteresis C_(60) thin film transistor

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Journal of Semiconductors 2011年第2期32卷 48-52页

作者：周建林陈仁钢 Department of Electronic Engineering College of Communication and ElectronicsChongqing University

Organic thin film transistors with C6O as an n-type semiconductor have been fabricated. A tantalum pentoxide （Ta2O5）/poly-methylmethacrylate （PMMA） double-layer structured gate dielectric was used. The Ta2O5 layer was prepared by using a simple solution-based and economical anodization technique. Our results demonstrate that double gate insulators can combine the advantage of Ta2O5 with high dielectric constant and polymer insulator for a better interface with the organic semiconductor. The performance of the device can be improved obviously with double gate insulators, compared to that obtained by using a single Ta205 or PMMA insulator. Then, a good performance n-type OTFT, which can work at 10 V with mobility, threshold voltage and on/off current ratio of, respectively, 0.26 cm2/（V.S）, 3.2 V and 8.31 × 10^4, was obtained. Moreover, such an OTFT shows a negligible ＂hysteresis effect＂ contributing to the hydroxyl-free insulator surface.

关键词： organic thin film transistors C60 double gate dielectrics

Antenna Selection and Power Allocation Design for 5G Massive MIMO Uplink Networks

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China communications 2019年第4期16卷 1-15页

作者： Hongyuan Gao Yumeng Su Shibo Zhang Ming Diao college of Information and communication Engineering Harbin Engineering University

Massive MIMO is one of the key technologies in future 5G communications which can satisfy the requirement of high speed and large capacity. This paper considers antenna selection and power allocation design to promote energy conservation then provide good quality of service(QoS) for the whole massive MIMO uplink network. Unlike previous related works, hardware impairment, transmission efficiency, and energy consumption at the circuit and antennas are involved in massive MIMO networks. In order to ensure the QoS, we consider the minimum rate constraint for each user and the system, which increases the complexity of power allocation problem for maximizing energy and spectral efficiency in massive MIMO system. To this end, a quantum-inspired social emotional optimization(QSEO) algorithm is proposed to obtain the optimal power control strategy in massive MIMO uplink networks. Simulation results assess the great advantages of QSEO which previous strategies do not have.

关键词： 5G massive MIMO antenna selection power allocation quantum-inspiredsocial emotional optimization

Improved Conditions for Global Asymptotic Stability of Cohen-Grossberg Neural Networks with Time-Varying Delays

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Chinese Physics Letters 2008年第11期25卷 3894-3897页

作者：陈君崔宝同高明 college of communication and Control Engineering Jiangnan University Wuxi 214122

The global asymptotic stability of delayed Cohen-Grossberg neural networks with impulses is investigated. Based on the new suitable Lyapunov functions and the Jacobsthal inequality, a set of novel sufficient criteria are derived for the global asymptotic stability of Cohen-Grossberg neural networks with time-varying delays and impulses. An illustrative example with its numerical simulations is given to demonstrate the effectiveness of the obtained results.

关键词： MATHEMATICAL physics -- Asymptotic theory NEURAL networks (Computer science) LYAPUNOV functions INEQUALITIES (Mathematics) NUMERICAL analysis SIMULATION methods & models