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IEEE International Conference on Communications (ICC)

作者： Ruiqi Wang Shibo He Jiming Chen Zhiguo Shi Fen Hou State Key Lab. of Industrial Control Technology Zhejiang University China Department of Electrical and Computer Engineering University of Macau Macau

ISBN: (纸本)9781467364300

By taking advantage of active radio waves, radar sensors can provide high-accuracy target detection over traditional passive sensors. In this paper, we study barrier coverage in bistatic radar sensor networks (BRSNs), which consist of a set of transmitter radars and receiver radars. Barrier coverage in BRSNs is much more difficult than that in traditional sensor networks as the sensing area of a bistatic radar depends on the positions of both transmitter and receiver, and is typically a Cassini oval. Moreover, different transmitters and receivers can pair with each other by choosing the same frequency and thus the sensing network topology can be quite different in different time slots. To tackle this challenge, we first investigate the characteristic of the ε-covered area of a bistatic radar, then we represent a bistatic radar with a virtual point at the middle point of the line segment formed by the transmitter and receiver. With these representations, we formulate the barrier coverage problem in BRSNs as (k, ε)-Minimum Weight Barrier Coverage Problem ((k, ε)-MWBCP). By constructing a directed coverage graph, we transform the (k, ε)-MWBCP into finding k node-disjoint shortest paths and propose an energy-efficient algorithm called (k, ε)-MWBCA to solve the problem within polynomial time. Extensive simulations are conducted to demonstrate the performance of our proposed algorithm.

关键词： Bistatic radar Receivers Belts Signal to noise ratio Radio transmitters

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Ultrasonic Power Closed-loop control on Wire Bonder

Ultrasonic Power Closed-loop Control on Wire Bonder

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IEEE ELectronics Packaging Technology Conference

作者： He Yunbo Hu Yongshan Chen Xin Gao Jian Yang Zhijun Zhang Kai Chen Yun Zhang Yu Tang Hui Ao Yinhui Guangdong Provincial Key Lab. of Computer Integrated Manufacturing Systems Key Laboratory of Mechanical Equipment Manufacturing and Control Technology of Ministry of Education School of Electromechanical Engineering Guangdong University of Technology

ISBN: (纸本)9781509043705

Ultrasonic is one important factor of ultrasonic wire bonding process, which is widely used in semiconductor packaging industry. control effect of ultrasonic power determines the quality and speed of wire bonding. Based on analysis of ultrasonic frequency characteristics and current response, this paper proposes a closed-loop control method of automatic frequency tracking and output current control, to improve the effectiveness of ultrasonic power, shorten the response time, and enhance the stability of ultrasonic generation. Automatic frequency tracking is based on phase lock method. Phase difference of voltage and current signals works as the feedback of the close-loop control of frequency to realize automatic frequency tracking and ensure that the ultrasonic transducer always works at resonance point. And output current control is working at constant current mode so that the vibration amplitude of ultrasonic can be better controlled by adjusting the ultrasonic current. The experimental results show that with the frequency automatic tracking method, the ultrasonic transducer system can achieve wider frequency bands, with faster phase locking and higher tracking precision. With close loop control, real-time tracking can be realized and less rise time and less overshoot of ultrasonic current can be achieved.

关键词： Ultrasonic Power Closed-loop

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Modeling parameter interactions in ranking SVM 15

Modeling parameter interactions in ranking SVM

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24th ACM International Conference on Information and Knowledge Management, CIKM 2015

作者： Zhang, Yaogong Xu, Jun Lan, Yanyan Guo, Jiafeng Xie, Maoqiang Huang, Yalou Cheng, Xueqi College of Computer and Control Engineering Nankai University China CAS Key Lab. of Network Data Science and Technology Institute of Computing Technology Chinese Academy of Sciences China College of Software Nankai University China

ISBN: (纸本)9781450337946

Ranking SVM, which formalizes the problem of learning a ranking model as that of learning a binary SVM on preference pairs of documents, is a state-of-the-art ranking model in information retrieval. The dual form solution of Ranking SVM model can be written as a linear combination of the preference pairs, i.e., w = Σ(i,j)αij(xi - xj), where αij denotes the Lagrange parameters associated with each pair (i,j). It is obvious that there exist significant interactions over the document pairs because two preference pairs could share a same document as their items. Thus it is natural to ask if there also exist interactions over the model parameters αij, which we may leverage to propose better ranking model. This paper aims to answer the question. Firstly, we found that there exists a low-rank structure over the Ranking SVM model parameters αij, which indicates that the interactions do exist. Then, based on the discovery, we made a modification on the original Ranking SVM model by explicitly applying a low-rank constraint to the parameters. Specifically, each parameter αij is decomposed as a product of two low-dimensional vectors, i.e., αij = (υi,υj), where vectors vi and vj correspond to document i and j, respectively. The learning process, thus, becomes to optimize the modified dual form objective function with respect to the low-dimensional vectors. Experimental results on three LETOR datasets show that our method, referred to as Factorized Ranking SVM, can outperform state-of-the-art baselines including the conventional Ranking SVM. © 2015 ACM.

关键词： Information retrieval

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Cooperative Spectrum Sensing Based on Double Thresholds Energy Detection over Imperfect Reporting Channels

Cooperative Spectrum Sensing Based on Double Thresholds Ener...

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International Conference on Instrumentation, Measurement, computer, Communication and control (IMCCC)

作者： Zi Zhang Xinbin Li Zhixin Liu Key Lab of Industrial Computer Control Engineering of Hebei Province Yanshan University Hebei China

ISBN: (纸本)9781467377249

In this paper, the problem of hierarchical cooperative spectrum sensing using double thresholds energy detector over imperfect reporting channels will be investigated. When taking error effect on reporting decision into consideration, the sensing performance will be affected. In the proposed scheme, we analyze the performance of hierarchical cooperative spectrum sensing over imperfect reporting channels and the "majority-decision-aided" weighting rule will be used in the fusion center. The analysis and simulation results show that there is a significant performance loss when the decisions based on hierarchical spectrum sensing are transmitted over imperfect reporting channels and the sensing performance is improved by employing the new weighting rule.

关键词： Sensors Cognitive radio Signal to noise ratio computers Propagation losses Reliability Fading channels

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controlling velocity of armature based on the multi-pulse forming network

Controlling velocity of armature based on the multi-pulse fo...

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International Conference on Pulsed Power

作者： Zhenchun Wang Zhiyong Bao Fucai Liu Lijie Jia Key Lab of Industrial Computer Control Engineering of Hebei Province Yanshan University QinHuangDao China

Given the accuracy of the muzzle velocity of railgun, based on the capacitive energy-stored type of pulse forming network, electromechanical model of railgun is established, a multistage multi-module velocity control strategy based on velocity closed-loop control is proposed. Through the simulate analyze of the multiple of PFU by using electromechanical model of railgun, the best PFU electrical parameters and the best multi-stage control strategy are obtained, test shows that the system model and the control strategy can be applied to the actual system experiment, and achieve good results.

关键词： Interference Load modeling Accuracy Velocity control Electromagnetics Capacitors

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Robust Iterative Learning control of Single-phase Grid-connected Inverter

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International Journal of Automation and computing 2014年第4期11卷 404-411页

作者： Zhong-Qiang Wu Chun-Hua Xu Yang Yang Key Lab of Industrial Computer Control Engineering of Hebei Province Yanshan University

For the single phase inductance-capacitance-inductance(LCL) grid-connected inverter in micro-grid, a kind of robust iterative learning controller is designed. Based on the output power droop characteristics of inverter, the current sharing among the inverters is achieved. Iterative learning strategy is suitable for repeated tracking control and inhibiting periodic disturbance, and is designed using robust performance index, so that it has the ability to overcome the uncertainty of system parameters. Compared with the repetitive control, the robust iterative learning control can get high precision output waveform, and enhance the tracking ability for waveform, and the distortion problem of the output signal can be solved effectively.

关键词： Inductance-capacitance-inductance (LCL) filter iterative learning robust control power droop-characteristics repetitive control

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Hydraulic System Reliability Modelling and Analysis Based on Convex Model Bayesian Network

Hydraulic System Reliability Modelling and Analysis Based on...

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2015 International Conference on Fluid Power and Mechatronics

作者： Dongning Chen Yuliang Zhang Chengyu Yao Shijun Lv Key Lab of Heavy Machinery Fluid Power Transmission and Control of Hebei Province Yanshan University Key Lab of Industrial Computer Control Engineering of Hebei Province Yanshan University

Compared with the probabilistic method, the nonprobabilistic convex model only requires a small number of samples and experiences to obtain the variation bounds of the ambiguous and imprecise parameters, and whereby makes the reliability analysis very convenient. In this paper, hydraulic lifting system reliability model is established and the reliability of the system is analyzed by convex model Bayesian network, then the reliability indices are described in the form of interval parameters. Using ellipsoid model to constrain interval model, the more accurate reliability indices are obtained. Finally the convex model Bayesian network is compared with traditional Bayesian network. All the reliability indices obtained by convex model Bayesian network provide the basis for condition-based maintenance, fault diagnosis and reliability design.

关键词： reliability analysis hydraulic system Bayesian network convex model

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Hydraulic System Reliability Modelling and Analysis Based on Convex Model Bayesian Network

Hydraulic System Reliability Modelling and Analysis Based on...

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International Conference of Fluid Power and Mechatronics

ISBN: (纸本)9781479987719

Compared with the probabilistic method, the non-probabilistic convex model only requires a small number of samples and experiences to obtain the variation bounds of the ambiguous and imprecise parameters, and whereby makes the reliability analysis very convenient. In this paper, hydraulic lifting system reliability model is established and the reliability of the system is analyzed by convex model Bayesian network, then the reliability indices are described in the form of interval parameters. Using ellipsoid model to constrain interval model, the more accurate reliability indices are obtained. Finally the convex model Bayesian network is compared with traditional Bayesian network. All the reliability indices obtained by convex model Bayesian network provide the basis for condition-based maintenance, fault diagnosis and reliability design.

关键词： Reliability analysis Hydraulic system Bayesian network Convex model

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Two-Stage Force Particle Swarm Optimization Algorithm and Application in Hydraulic System Reliability Optimization

Two-Stage Force Particle Swarm Optimization Algorithm and Ap...

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2015 International Conference on Fluid Power and Mechatronics

作者： Chengyu Yao Xueyun Tan Dongning Chen Shijun Lv Key Lab of Industrial Computer Control Engineering of Hebei Province Yanshan University Key Lab of Heavy Machinery Fluid Power Transmission and Control of Hebei Province Yanshan University

In view of the particle swarm optimization(PSO) algorithm's shortages of easily trapping into local optimum and premature convergence, an improvement research from the perspective of interaction mechanism among particles is made in this paper. Consider advantages and disadvantages of the current improved PSO algorithms from the aspect of force, the two-stage force particle swarm optimization(TFPSO) algorithm is proposed. The proposed algorithm, which employs staged search strategy to achieve a trade-off between global exploration and local exploitation abilities, divides search process into two stages and constructs corresponding force rules combining with the idea of attractive and repulsive forces in artificial physics. In order to demonstrate the performance of the proposed algorithm in solving optimization problems, TFPSO algorithm is compared with some well-known PSO algorithms in reliability optimization for hydraulic system. Comparison results show that TFPSO algorithm obtains the best optimization results and enhances the performance of PSO in terms of accuracy of the optimal solution and local search ability.

关键词： PSO algorithm force rule TFPSO algorithm reliability optimization hydraulic system

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Privacy Preserving Maximum Consensus

Privacy Preserving Maximum Consensus

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IEEE Annual Conference on Decision and control

作者： Xiaoming Duan Jianping He Peng Cheng Yilin Mo Jiming Chen The State Key Lab. of Industrial Control Technology Zhejiang University China School of Electrical and Electronics Engineering Nanyang Technological University

ISBN: (纸本)9781479978878

Maximum consensus is useful in many applications such as leader selection and time synchronization, and it is advantageous for its decentralization and finite time convergence. However, without preservation mechanisms for maximum consensus, nodes' initial states and especially the identity of the node with the maximum initial state will be disclosed, which is undesirable in some application scenarios. To preserve the privacy of maximum consensus while maintaining its advantages, we propose a Privacy Preserving Maximum Consensus (PPMC) algorithm, where all nodes independently generate and transmit random numbers before sending out their initial states. We prove that PPMC converges in finite time. Meanwhile, explicit formulas are given to characterize the probability that the maximum state owner's identity is inferred by its neighbors. Extensive simulations are conducted to demonstrate the effectiveness of the proposed algorithm.

关键词： Privacy Convergence Nickel Security Topology Network topology Broadcasting

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