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Research of improving the dynamic scheduling algorithm in the CAN bus control networks

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Journal of Systems Engineering and Electronics 2008年第6期19卷 1250-1257页

作者： Wang Liming Shao Ying Wang Mingzhe Shan Yong Electric and information coll. Naval Engineering Univ. Wuhan 430033 P. R. China Huazhong Univ. of science and Technology Wuhan 430074 P. R. China

Currently, the article analyzes the CAN bus＇s rule of priority＇s arbitration bit by bit without destroy. It elicits the conclusion that if static priority based on the affirmatory system model is used, the lower priority＇s messages will be delayed considerably more, even some data will be lost when the bus＇s bandwidth is widely used. The scheduling cannot be modified neither during the system when static priority is used. The dynamic priority promoting method and the math model of SQSA and SQMA are presented; it analyzes the model＇s rate of taking in and sending out in large quantities, the largest delay, the problems and solutions when using SQMA. In the end, it is confirmed that the method of improving dynamic priority has good performances on the network rate of taking in and sending out in large quantities, the average delay, and the rate of network usage by emulational experiments.

关键词： CAN static scheduling dynamic scheduling single queue single algorithm single queue multi algo-rithm average delay network load rate

Time-delay Compensation Method for Networked Control System Based on Time-delay Prediction and Implicit PIGPC

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International Journal of Automation and computing 2015年第6期12卷 648-656页

作者： Zhong-Da Tian Xian-Wen Gao Bi-Lian Gong Tong Shi School of information science and Engineering Shenyang University of Technology School of information science and Engineering Northeastern University Department of Humanities Liaoning Forestry Vocation-Technical College

A network time-delay compensation method based on time-delay prediction and implicit proportional-integral-based generalized predictive controller(PIGPC) is proposed. The least squares support vector machine(LSSVM) is used to predict the current time-delay, the parameters of the least squares support vector machine are optimized by particle swarm optimization(PSO) algorithm,and the predicted time-delay is used instead of the actual time-delay as the parameters of the network time-delay compensation controller. In order to improve the compensation effect of implicit generalized predictive controller(GPC), this paper puts forward an implicit generalized predictive control algorithm with proportional-integral-based(PI) structure and designs the controller based on implicit PIGPC. Through the simulation results, the effectiveness of this design in the paper is verified.

关键词： Networked control system time-delay compensation p

Multi-attribute decision making model based on optimal membership and relative entropy

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Journal of Systems Engineering and Electronics 2009年第3期20卷 537-542页

作者： Rao Congjun Zhao Yong Inst. of Systems Engineering Huazhong Univ. of Science and Technology Wuhan 430074 P. R. China coll. of Mathematics and information science Huanggang Normal Univ. Huanggang 438000 P. R. China

To study the problems of multi-attribute decision making in which the attribute values are given in the form of linguistic fuzzy numbers and the information of attribute weights are incomplete, a new multi-attribute decision making model is presented based on the optimal membership and the relative entropy. Firstly, the definitions of the optimal membership and the relative entropy are given. Secondly, for all alternatives, a set of preference weight vectors are obtained by solving a set of linear programming models whose goals axe all to maximize the optimal membership. Thirdly, a relative entropy model is established to aggregate the preference weight vectors, thus an optimal weight vector is determined. Based on this optimal weight vector, the algorithm of deviation degree minimization is proposed to rank all the alternatives. Finally, a decision making example is given to demonstrate the feasibility and rationality of this new model.

关键词： multi-attribute decision making optimal membership relative entropy deviation degree

Virtualized Platform for Multicast Services in Software Defined Networks

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Chinese Journal of Electronics 2017年第3期26卷 453-459页

作者： LIAO Shengquan WU Chunming HONG Xiaoyan ZHU Kai CHEN Shuangxi coll.ge of Computer science and Technology Zhejiang University Department of Computer science The University of Alabama Division of information Technology Jiaxing Vocational Technical College

With the growing trend of deploying Software defined networks(SDN) in Internet and data centers,it is necessary to investigate the operation of multicast services in this paradigm shift. We propose an Open Flowbased virtualized platform to support multiple multicast services simultaneously, each with their own customized multicast algorithms and performance-enhancing strategies for its service requirements. The contributions include:1) systematic discussions of the technical challenges regarding to implementing multicast services in SDN, with the proposed architectural components addressing these issues; 2) a virtualized platform enabling user-defined multicast services, independent of current Internet-based protocols; 3) experiments validating the necessity and efficiency of the platform in supporting its design goals and functionalities, with two additional real multicast applications further confirming the feasibility and operability of the proposed prototype.

关键词： Customized multicast service Open Flow Software defined networks(SDN)

Decentralized and overall condition monitoring system for large-scale mobile and complex equipment

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Journal of Systems Engineering and Electronics 2007年第4期18卷 758-763页

作者： Cao Jianjun Zhang Peilin Ren Guoquan Fu Jianping Dept. of Artillery Engineering Mechanical Engineering Coll. Shijiazhuang 050003 P. R. China coll. of Mechanical Engineering Nanjing Univ. of Science and Technology Nanjing 210094 P. R. China

It is an urgent project to realize online and overall condition monitoring and timely fault diagnosis for large-scale mobile and complex equipment. Moreover, most of the existing large-scale complex equipment has quite insufficient accessibility of examination, although it still has quite a long service life. The decentralized and overall condition monitoring, as a new concept, is proposed from the point of view of the whole system. A set of complex equipment is divided into several parts in terms of concrete equipment. Every part is processed via one detecting unit, and the main detecting unit is connected with other units. The management work and communications with the remote monitoring center have been taken on by it. Consequently, the difficulty of realizing a condition monitoring system and the complexity of processing information is reduced greatly. Furthermore, excellent maintainability of the condition monitoring system is obtained because of the modularization design. Through an application example, the design and realization of the decentralized and overall condition monitoring system is introduced specifically. Some advanced technologies, such as, micro control unit （MCU）, advanced RISC machines （ARM）, and control area network （CAN）, have been adopted in the system. The system＇s applicability for the existing large-scale mobile and complex equipment is tested.

关键词： condition monitoring fault diagnosis micro control unit information fusion

PD-type iterative learning control for nonlinear time-delay system with external disturbance

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Journal of Systems Engineering and Electronics 2006年第3期17卷 600-605页

作者： Zhang Baolin Tang Gongyou Zheng Shi coll. of information science and Engineering Ocean Univ. of China Qingdao 266071 P. R. China Dept. of information and Mathematics sciences China Jiliang Univ. Hangzhou 310018 P.R. China

The PD-type iterative learning control design of a class of affine nonlinear time-delay systems with external disturbances is considered. Sufficient conditions guaranteeing the convergence of the n-norm of the tracking error are derived. It is shown that the system outputs can be guaranteed to converge to desired trajectories in the absence of external disturbances and output measurement noises. And in the presence of state disturbances and measurement noises, the tracking error will be bounded uniformly. A numerical simulation example is presented to validate the effectiveness of the proposed scheme.

关键词： time-delay system nonlinear system iterative learning control convergence external disturbance.

Rule Generation Based on Dominance Matrices and Functions

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Transactions of Tianjin University 2004年第1期10卷 54-58页

作者：安利平陈增强袁祉仝凌云 coll.ge of International Business Nankai UniversityTianjin 300071ChinaCollege of Information Technical Science Nankai UniversityTianjin 300071 China coll.ge of information technical science Nankai University

Rough set theory has proved to be a useful tool for rule induction. But, the theory based on indiscernibility relation or similarity relation cannot induce rules from decision tables with criteria. Greco et al have proposed a new rough set approach based on dominance relation to handle the problems. The concept of dominance matrix is put forward and the dominance function is constructed to compute the minimal decision rules which are more general and applicable than the ones induced by the classical rough set theory. In addition, the methodology of simplification is presented to eliminate the redundancy in the rule set.

关键词： Decision tables Mathematical techniques

New direction of arrival estimation method for wideband coherent signals

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Journal of Systems Engineering and Electronics 2008年第3期19卷 473-478页

作者： Wang Ling Yin Jihao Chen Tianqi coll. of Electronic Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

To estimate the direction-of-arrival （DOA） of wideband coherent signals, a new method by modifying the orthogonality of the projected suhspaces method is proposed. And it can deal with randomly position perturbed arrays by using the Toeplitz method. This method needn＇t the primary information of DOA for focusing matrix and the sector dividing of interpolated method, which improving the precision of estimation and reducing the computational complexity. Simulations illustrate the effectiveness of this method.

关键词： DOA estimation array signal processing orthogonal projection array perturbation wideband coherent signals

Approach to Anomaly Traffic Detection in a Local Network

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Journal of Donghua University(English Edition) 2009年第6期26卷 656-661页

作者：王秀英肖立中邵志清 Department of Computer information Shanghai Xinqiao Vocational and Technical College School of information science and Engineering East China University of Science and Technology Department of Computer science and information Engineeting Shanghai Institute of Technology

The research intends to solve the problem of the occupation of bandwidth of local network by abnormal traffic which affects normal user's network ***,a new algorithm in this paper named danger-theory-based abnormal traffic detection was *** an advanced ID3 algorithm was presented to classify the abnormal *** a new model of anomaly traffic detection was built upon the two algorithms above and the detection results were integrated with *** firewall limits the bandwidth based on different types of abnormal *** show the outstanding performance of the proposed approach in real-time property,high detection rate,and unsupervised learning.

关键词： clanger theory information enlropy ID3 algorithm abnormal traffic