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Chinese Journal of Electronics 2019年第2期28卷 237-245页

作者： WEN Quangang LIANG Yanchun Adriano Tavares Ricardo Teixeira WU Chunguo Key Laboratory of Symbol Computation and Knowledge Engineering of Ministry of Education College of Computer Science and Technology Jilin University Zhuhai Laboratory of Key Laboratory of Symbol Computation and Knowledge Engineering of Ministry of Education Zhuhai College of Jilin University Department of Industrial Electronics University of Minho Campus de Azurm

The servo motor’s flexible acceleration/deceleration(acc/dec) control is an emerging research topic in the automation field. A velocity control algorithm based on trigonometric function is proposed in this paper.With required parameters, it transforms trigonometric calculations into elementary mathematical operations and calculates the velocity controlling values iteratively, which could avoid trigonometric calculation and reduce the computation time. Experimental results show that the proposed algorithm is suitable for implementation on field programmable gate arrays and achieves a flexible controlling, enhancing both the equipment’s stability and reliability. It is promising to significantly improve the high-speed computerized numerical control equipment’s controlling accuracy, without a huge hardware resource consumption.

关键词： Acceleration Velocity control algorithm design and analysis Field programmable gate arrays Servomotors

Fast and scalable routing protocols for data center networks

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Digital Communications and Networks 2023年第6期9卷 1340-1350页

作者： Mihailo Vesovic Aleksandra Smiljanic Dusan Kostic School of Electrical Engineering University of Belgrade11120BelgradeSerbia Amazon Web Services(AWS) ZurichSwitzerland

Data center networks may comprise tens or hundreds of thousands of nodes,and,naturally,suffer from frequent software and hardware failures as well as link congestions.Packets are routed along the shortest paths with sufficient resources to facilitate efficient network utilization and minimize delays.In such dynamic networks,links frequently fail or get congested,making the recalculation of the shortest paths a computationally intensive problem.Various routing protocols were proposed to overcome this problem by focusing on network utilization rather than speed.Surprisingly,the design of fast shortest-path algorithms for data centers was largely neglected,though they are universal components of routing protocols.Moreover,parallelization techniques were mostly deployed for random network topologies,and not for regular topologies that are often found in data centers.The aim of this paper is to improve scalability and reduce the time required for the shortest-path calculation in data center networks by parallelization on general-purpose hardware.We propose a novel algorithm that parallelizes edge relaxations as a faster and more scalable solution for popular data center topologies.

关键词： Routing protocols Data center networks Parallel algorithms Distributed algorithms algorithm design and analysis Shortest-path problem Scalability

algorithms for automatic measurement of SIS-type hysteretic underdamped Josephson junction’s parameters by current-voltage characteristics

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Journal of Electronic Science and Technology 2023年第4期21卷 60-74页

作者： Aleksey G.Vostretsov Svetlana G.Filatova Laboratory of Quantum Cryogenic Electronics Novosibirsk State Technical UniversityNovosibirsk630073Russia Chinakal Institute of Mining Siberian BranchRussian Academy of SciencesNovosibirsk630091Russia

Some electrical parameters of the SIS-type hysteretic underdamped Josephson junction(JJ)can be measured by its current-voltage characteristics(IVCs).Currents and voltages at JJ are commensurate with the intrinsic noise level of measuring instruments.This leads to the need for multiple measurements with subsequent statistical processing.In this paper,the digital algorithms are proposed for the automatic measurement of the JJ parameters by IVC.These algorithms make it possible to implement multiple measurements and check these JJ parameters in an automatic mode with the required accuracy.The complete sufficient statistics are used to minimize the root-mean-square error of parameter measurement.A sequence of current pulses with slow rising and falling edges is used to drive JJ,and synchronous current and voltage readings at JJ are used to realize measurement algorithms.The algorithm performance is estimated through computer simulations.The significant advantage of the proposed algorithms is the independence from current source noise and intrinsic noise of current and voltage meters,as well as the simple implementation in automatic digital measuring systems.The proposed algorithms can be used to control JJ parameters during mass production of superconducting integrated circuits,which will improve the production efficiency and product quality.

关键词： algorithm design and analysis Critical current Current-voltage characteristics(IVCs) Josephson junction(JJ) Measurement errors Parameter estimation

Application of algorithm CARDBK in Document Clustering

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Wuhan University Journal of Natural Sciences 2018年第6期23卷 514-524页

作者： ZHU Yehang ZHANG Mingjie SHI Feng College of Economics and Management Xi'an University of Posts and Telecommunications Xi'an 710121 Shaanxi China Information Business Department Puyang Technician College Puyang 457000 Henan China

In the K-means clustering algorithm, each data point is uniquely placed into one category. The clustering quality is heavily dependent on the initial cluster centroid. Different initializations can yield varied results; local adjustment cannot save the clustering result from poor local optima. If there is an anomaly in a cluster, it will seriously affect the cluster mean value. The K-means clustering algorithm is only suitable for clusters with convex shapes. We therefore propose a novel clustering algorithm CARDBK—＂centroid all rank distance（CARD）＂ which means that all centroids are sorted by distance value from one point and ＂BK＂ are the initials of ＂batch K-means＂—in which one point not only modifies a cluster centroid nearest to this point but also modifies multiple clusters centroids adjacent to this point, and the degree of influence of a point on a cluster centroid depends on the distance value between this point and the other nearer cluster centroids. Experimental results showed that our CARDBK algorithm outperformed other algorithms when tested on a number of different data sets based on the following performance indexes： entropy, purity, F1 value, Rand index and normalized mutual information（NMI）. Our algorithm manifested to be more stable, linearly scalable and faster.

关键词： algorithm design and analysis clustering documentanalysis text processing

An Adaptive Obstacle Avoidance algorithm for Unmanned Surface Vehicle in Complicated Marine Environments

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IEEE/CAA Journal of Automatica Sinica 2014年第4期1卷 385-396页

作者： Rubo Zhang Pingpeng Tang Yumin Su Xueyao Li Ge Yang Changting Shi the College of Computer Science and Technology Harbin Engineering UniversityHarbin 150001China College of Electromechanical and Information Dalian Nationalities University the College of Computer Science and Technology Harbin Engineering UniversityHarbin 150001China Wuhan Second Ship design and Research Institute the National Key Laboratory of Science and Technology on Autonomous Underwater Vehicle Harbin Engineering University

Unmanned surface vehicles(USVs) are important autonomous marine robots that have been studied and gradually applied into practice. However, the autonomous navigation of USVs, especially the issue of obstacle avoidance in complicated marine environment, is still a fundamental problem. After studying the characteristics of the complicated marine environment, we propose a novel adaptive obstacle avoidance algorithm for USVs,based on the Sarsa on-policy reinforcement learning algorithm.The proposed algorithm is composed of local avoidance module and adaptive learning module, which are organized by the “divide and conquer” strategy-based architecture. The course angle compensation strategy is proposed to offset the disturbances from sea wind and currents. In the design of payoff value function of the learning strategy, the course deviation angle and its tendency are introduced into action rewards and penalty policies. The validity of the proposed algorithm is verified by comparative experiments of simulations and sea trials in three sea-state marine environments. The results show that the algorithm can enhance the autonomous navigation capacity of USVs in complicated marine environments.

关键词： algorithm design and analysis Collision avoidance Learning (artificial intelligence) Marine technology Mobile robots Navigation Sea surface Unmanned aerial vehicles “divide and conquer” strategy Sarsa on-policy reinforcement learning algorithm Unmanned surface vehicle adaptive obstacle avoidance algorithm complicated marine environment Obstacle avoidance vehicle UNMANNED sublittoral zone Unmanned Aerial Vehicle algorithm design and analysis Divide and conquer navigation Marine technology Ground vehicles drone honey bees Collision avoidance algorithms sea surface Mobile robots

Clique-based Cooperative Multiagent Reinforcement Learning Using Factor Graphs

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IEEE/CAA Journal of Automatica Sinica 2014年第3期1卷 248-256页

作者： Zhen Zhang Dongbin Zhao the State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of Sciences Department of Electric Engineering College of Automation EngineeringQingdao University

In this paper,we propose a clique-based sparse reinforcement learning(RL) algorithm for solving cooperative tasks.The aim is to accelerate the learning speed of the original sparse RL algorithm and to make it applicable for tasks decomposed in a more general manner.First,a transition function is estimated and used to update the Q-value function,which greatly reduces the learning time.Second,it is more reasonable to divide agents into cliques,each of which is only responsible for a specific subtask.In this way,the global Q-value function is decomposed into the sum of several simpler local Q-value functions.Such decomposition is expressed by a factor graph and exploited by the general maxplus algorithm to obtain the greedy joint action.Experimental results show that the proposed approach outperforms others with better performance.

关键词： Sensors Games Learning (artificial intelligence) Approximation algorithms algorithm design and analysis Heuristic algorithms Sparse matrices

Distributed Average Consensus in Multi-agent Networks with Limited Bandwidth and Time-delays

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IEEE/CAA Journal of Automatica Sinica 2014年第2期1卷 193-203页

作者： Wenhui Liu Feiqi Deng Jiarong Liang Haijun Liu College of Automation Science and Engineering South China University of Technology School of Computer Electronics and InformationGuangxi University School of Mathematics and Statistics Zhengzhou University

This paper studies the distributed average consensus problem of multi-agent digital networks with time-delays. For the network, each agent can only exchange symbolic data with its neighbours. We provide a distributed average consensus protocol which uses the quantized and time-delay information. We consider two types of dynamic encoders/decoders in our protocol.One uses inverse proportion function as scaling function, while the other uses exponential function as scaling function. All agents can reach average consensus asymptotically with our protocol.Furthermore, we show that the average consensus protocol is robust to finite symmetric time-delays, but is sensitive to asymmetric time-delays that will destroy the average consensus of the networks. Finally, simulations are presented to illustrate validity of our theoretical results.

关键词： algorithm design and analysis Bandwidth Communication channels Decoding Protocols Quantization (signal) Multi-agent networks average consensus communication constraints quantization time-delays NETWORKING AGENT Bandwidth Quantization time delay scaling function algorithm design and analysis Communication channels DECODING protocols

Remote monitoring cost minimization for an unreliable sensor network with guaranteed network throughput

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Information Processing in Agriculture 2014年第2期1卷 83-94页

作者： Xu Xu Weifa Liang Zichuan Xu Research School of Computer Science The Australian National UniversityCanberraACT 2601Australia

In this paper we consider a link-unreliable remote monitoring scenario where the monitoring center is geographically located far away from the region of the deployed sensor network,and sensing data by the sensors in the network will be transferred to the remote monitoring center through a third party telecommunication service.A cost associated with this service will be incurred,which will be determined by the number of gateways employed and the cumulative volume of data successfully received within a specified monitoring period.For this scenario,we first formulate a novel constrained optimization problem with an objective to minimize the service cost while a pre-defined network throughput is guaranteed.We refer to this problem as the throughput guaranteed service cost minimization problem and prove that it is NP-complete.We then propose a heuristic for it.The key ingredients of the heuristic include identifying gateways and finding an energy-efficient forest of routing trees rooted at the gateways.We also perform theoretical analysis on the solution obtained.Finally,we conduct experiments by simulations to evaluate the performance of the proposed algorithm.Experimental results demonstrate the proposed algorithm outperforms other algorithms in terms of both the service cost and the network lifetime.

关键词： Remote sensing monitoring Wireless sensor networks Service cost minimization Constrained optimization algorithm design and analysis

Parameters Tuning of Model Free Adaptive Control Based on Minimum Entropy

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IEEE/CAA Journal of Automatica Sinica 2014年第4期1卷 361-371页

作者： Chao Ji Jing Wang Liulin Cao Qibing Jin the China National Offshore Oil Corporation Research Institute the College of Information Science and Technology Beijing University of Chemical Technology

Dynamic linearization based model free adaptive control(MFAC) algorithm has been widely used in practical systems, in which some parameters should be tuned before it is successfully applied to process industries. Considering the random noise existing in real processes, a parameter tuning method based on minimum entropy optimization is proposed,and the feature of entropy is used to accurately describe the system uncertainty. For cases of Gaussian stochastic noise and non-Gaussian stochastic noise, an entropy recursive optimization algorithm is derived based on approximate model or identified model. The extensive simulation results show the effectiveness of the minimum entropy optimization for the partial form dynamic linearization based MFAC. The parameters tuned by the minimum entropy optimization index shows stronger stability and more robustness than these tuned by other traditional index,such as integral of the squared error(ISE) or integral of timeweighted absolute error(ITAE), when the system stochastic noise exists.

关键词： Adaptive control algorithm design and analysis Entropy Heuristic algorithms Learning (artificial intelligence) Mathematical model Noise measurement Stochastic processes Tuning Mode free adaptive control minimum entropy optimization index non-Gaussian stochastic noise parameter tuning Stochastic Processes entropy Mathematical Model tuning Shot noise system uncertainties algorithm design and analysis Heuristic algorithms Noise measurement Markov chain adaptive control