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Approach to WTA in air combat using IAFSA-IHS algorithm

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Journal of Systems Engineering and Electronics 2018年第3期29卷 519-529页

作者： LI Zhanwu CHANG Yizhe KOU Yingxin YANG Haiyan XU An LI You college of Electronic communication Northwestern Polytechnical University Aeronautics Engineering college Air Force Engineering University

In this paper, a static weapon target assignment（WTA）problem is studied. As a critical problem in cooperative air combat,outcome of WTA directly influences the battle. Along with the cost of weapons rising rapidly, it is indispensable to design a target assignment model that can ensure minimizing targets survivability and weapons consumption simultaneously. Afterwards an algorithm named as improved artificial fish swarm algorithm-improved harmony search algorithm（IAFSA-IHS） is proposed to solve the problem. The effect of the proposed algorithm is demonstrated in numerical simulations, and results show that it performs positively in searching the optimal solution and solving the WTA problem.

关键词： air combat weapon target assignment improved artificial fish swarm algorithm-improved harmony search algorithm(IAFSA-IHS) artificial fish swarm algorithm(AFSA) harmony search(HS)

Circuitry implementation of a novel nonautonomous hyperchaotic Liu system based on sine input

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Chinese Physics B 2009年第8期18卷 3304-3308页

作者：罗小华 college of communication and Information Engineering Chongqing University of Posts and Telecommunications

Based on the three-dimensional Liu system with a nonlinear term of square, this paper appends a state variable to the system, and further adds a driving signal of the sine signal to construct a novel 4-demensional nonautonomous hyperchaotic Liu system. The appended variable is formed by the product of the nonlinear quadratic term of the original state variables and the driving signal. Through adjusting the frequency of the driving signal, the system can be controlled to show some different dynamic behaviors. By numerical simulations, the Lyapunov exponent spectrums, bifurcation diagrams and phase diagrams of the novel systems are analyzed. Furthermore, the corresponding hardware circuits are implemented. Both the experimental results and the simulation results confirm that the method is feasible. The method, which adjusts the frequency of the input sine signal to control the system to show different dynamic behaviors, can make the dynamic property of the system become more complex, but easier to be controlled accurately as well.

关键词： chaos hyperchaos Liu system frequency control

Tunable time delay in active fiber Bragg grating coupler

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Optoelectronics Letters 2012年第6期8卷 433-436页

作者：李齐良王紫阳张勇王天枢曾然胡淼 Institute of communication and Information College of Communication EngineeringHangzhou Dianzi University

Slowing down velocity and controlling time delay of optical pulses in fiber have many potential applications in optical com-munication systems,and a number of theoretical and experimental studies have been *** this paper,the transmission spectrum and reflective spectrum of active fiber Bragg grating(FBG)couplers are studied,and the analytic expressions of dispersion and time delay are *** changing the detuning and gain coefficient,different dispersions and time delays in active fiber Bragg grating coupler are *** results show that different detunings and gain coefficients can result in various time delays,and thus tunable time delay could be achieved by changing signal frequency or gain coefficient.

关键词： Fiber Bragg gratings Fibers

Unvoiced/voiced classification and voiced harmonic parameters estimation using the third-order statistics

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 85-89页

作者： YING Na ZHAO Xiao-hui DONG Jing communication Engineering college of Hangzhou Dianzi University Hangzhou 310018 China communication Engineering college of Jilin University Changchun 130022 China

Unvoiced/voiced classification of speech is a challenging problem especially under conditions of low signal-to-noise ratio or the non-white-stationary noise environment. To solve this problem, an algorithm for speech classification, and a technique for the estimation of palrwise magnitude frequency in voiced speech am proposed. By using third order spectrum of speech signal to remove noise, in this algorithm the least spectrum difference to get refined pitch and the max harmonic number is given. And this algorithm utilizes spectral envelope to estimate signal-to-noise ratio of speech harmonics. Speech classification, voicing probability, and harmonic parameters of the voiced frame can be obtained. Simulation results indicate that the proposed algorithm, under complicated background noise, especially Gaussian noise, can effectively classify speech in high accuracy for voicing probability and the voiced parameters.

关键词： unvoiced/voiced classification harmonic extraction,the third-order eumulant sinusoidal speech model

Analysis of M-LWDF fairness and an enhanced M-LWDF packet scheduling mechanism

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 82-88页

作者： XIAN Yong-ju TIAN Feng-chun XU Chang-biao YANG Yue college of communication Engineering Chongqing University Chongqing 400030 China college of communication and Information Engineering Chongqing University of Posts and Telecommanications Chongqing 400065 China

Modified largest weighted delay first （M-LWDF） is a typical packet scheduling algorithm for supporting hybrid real-time services over wireless networks. However, so far, there is little literature available regarding the theoretic analysis of M-LWDF fairness. This paper gives a theoretic analysis of M-LWDF fairness, which shows that M-LWDF fairness is related to channel condition, packet＇s arrival process and the ratio of quality of service （QoS） requirements of different service queues. Given service QoS requirements and other parameters related to channel model and packet＇s arrival process, the fairness is merely related to the ratio of the number of users in the service queues. Based on the analysis, an enhanced M-LWDF algorithm （EM-LWDF） is proposed and demonstrated in this paper. EM-LWDF is strictly designed in light of the fairness criteria of QoS requirements, so its fairness is almost not related to the ratio of the number of users in the service queues, and the theoretical value of fairness index is equal to 1. Simulation results validate the theoretic analysis and show the effectiveness of EM-LWDF in improving fairness.

关键词： wireless resource management packet scheduling QoS M-LWDF EM-LWDF

New Feedback Control Model in the Lattice Hydrodynamic Model Considering the Historic Optimal Velocity Difference Effect

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communications in Theoretical Physics 2018年第12期69卷 803-807页

作者： Guang-Han Peng Shu-Hong Yang Hong-Zhuan Zhao college of Physics and Electronics Hunan University of Arts and Science college of Physical Science and Technology Guangxi Normal University School of Computer Science and communication Engineering Guangxi University of Science and Technology college of Architecture and Transportation Engineering Guilin University of Electronic Technology

A feedback control model of lattice hydrodynamic model is proposed by taking the information of the historic optimal velocity into account for the traffic system. The modern control theory is applied for the linear stability condition with feedback control signal. The result shows that the stability of traffic flow is closely related to the information of the historic optimal velocity. Furthermore, numerical simulations conform that the new feedback control did increase the stability of traffic flow efficiently, which is in accord with theoretical analysis.

关键词： traffic flow lattice hydrodynamic model control method traffic jam

Energy adaptive MAC protocol for IEEE 802.15.7 with energy harvesting

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Optoelectronics Letters 2016年第5期12卷 370-374页

作者：汪红桥迟学芬赵琳琳 college of communication Engineering Jilin University

The medium access control(MAC) protocol for indoor visible light communication(VLC) with energy harvesting is explored in this paper. The unfairness of throughput exists among devices due to the significant difference of their energy harvesting rates which changes with distance, acceptance angle and the obstruction probability. We propose an energy harvesting model, a new obstruction probability model and an energy adaptive contention algorithm to overcome the unfairness problem. This device can adjust its contention window according to the energy harvesting rate. As a result, the device with lower energy harvesting rate can get shorter contention window to improve its transmission opportunity. Simulation results show that our MAC protocol can achieve a higher degree of fairness.

关键词： harvesting throughput opportunity obstruction adjust transmit overcome acket acceptance CSMA

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

Research on image sentiment analysis technology based on sparse representation

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CAAI Transactions on Intelligence Technology 2022年第3期7卷 354-368页

作者： Xiaofang Jin Yinan Wu Ying Xu Chang Sun college of Information and communication Engineering Communication University of ChinaBeijingChina Academy of Broadcasting Science BeijingChina

Many methods based on deep learning have achieved amazing results in image sentiment ***,these existing methods usually pursue high accuracy,ignoring the effect on model training *** that when faced with large-scale sentiment analysis tasks,the high accuracy rate often requires long experimental *** view of the weakness,a method that can greatly improve experimental efficiency with only small fluctuations in model accuracy is proposed,and singular value decomposition(SVD)is used to find the sparse feature of the image,which are sparse vectors with strong discriminativeness and effectively reduce redundant information;The authors propose the Fast Dictionary Learning algorithm(FDL),which can combine neural network with sparse *** method is based on K-Singular Value Decomposition,and through iteration,it can effectively reduce the calculation time and greatly improve the training efficiency in the case of small fluctuation of ***,the effectiveness of the proposed method is evaluated on the FER2013 *** adding singular value decomposition,the accuracy of the test suite increased by 0.53%,and the total experiment time was shortened by 8.2%;Fast Dictionary Learning shortened the total experiment time by 36.3%.

关键词： FDL image sentiment analysis model efficiency sparse representation SVD