检索结果-内蒙古大学图书馆

Analysis of security in cyber-physical systems

Science China. Technological Sciences 2017年第12期60卷 1975-1977页

作者： Chen Jie Zhang Fan Sun Jian School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081

In recent years, cyber-physical systems (CPSs) have received much attention from both the academic world and the industrial world, which refer to a deep integration and coordination of physical and computational resources [1,2]. Typical examples of CPSs can be found in smart grids, smart transportation systems, industrial control systems, water supply systems, and so on. Furthermore, many military systems are also CPSs. The key characteristic of CPSs is the integration of computing, control and communication. The increased interconnection between the cyber and physical spaces make CPSs vulnerable to various malicious attacks. A well-known example of an attack of CPSs is the Stuxnet which infected the control system of nuclear-fuel centrifuges of Bushehr nuclear power plant in Iran. Stuxnet makes people beware of the grave consequences of a cyber-attack on a CPS. Since many national critical infrastructures are applications of CPS, ensuring security and safety of such systems is of great importance.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Optimal switching integrity attacks in cyber-physical systems

Optimal switching integrity attacks in cyber-physical system...

引用

Youth Academic Annual Conference of Chinese Association of Automation (YAC)

作者： Guangyu Wu Jian Sun The Key Laboratory of Intelligent Control and Decision of Complex System Beijing Institute of Technology Beijing China

ISBN: (纸本)9781538629024

In this paper, an optimal switching data integrity attack schedule method is presented. It is assumed that an attacker is able to inject false data to partial actuators of a healthy system at each instant. Optimal switching attack represents a growing class of cyber-physical attacks that aim to damage a target system via a controlled switching of attacked units. A feedback attack law is proposed to maximize a weighted quadratic performance. Two switching conditions are designed to obtain the optimal sequence of the attacked actuators via the Maximum Principle. Finally, numerical results are provided to illustrate the effectiveness of the proposed method.

关键词： Switches Actuators Cyber-physical systems Jamming Optimal control System performance

来源：评论

学校读者我要写书评

暂无评论

Torque Ripple Reduction of a Modular-Stator Outer-Rotor Flux-Switching Permanent-Magnet Motor

Torque Ripple Reduction of a Modular-Stator Outer-Rotor Flux...

引用

Annual Conference of the IEEE Industrial Electronics Society

作者： Jing Zhao Yun Zheng Congcong Zhu Hao Chen Liu Yang Key laboratory for Intelligent Control & Decision of Complex Systems Beijing Institute of Technology Beijing China

In order to reduce the permanent magnet (PM) volume and combine the advantages of in-wheel motor, a novel modular-stator outer-rotor flux-switching permanent-magnet motor (MSOR-FSPM) whose PM volume is half of that in conventional outer-rotor flux-switching permanent-magnet (COR-FSPM) motor is proposed. However, cogging torque and torque ripple of MSOR-FSPM motor are especially worse due to the inherent double salient effect and the back-EMF harmonics caused by module stator structure. In this paper, structure and operation principle of MSOR-FSPM motor are described simply. Secondly, cogging torque and torque ripple are reduced by using traditional rotor two-step skewing method, but the result is unsatisfactory. Thirdly, a new rotor two-step skewing method is adopted since the ratio of back-EMF period to cogging torque period is the odd. Compared with traditional rotor step skewing method, the new method eliminates the even harmonics of back-EMF and remains the amplitude of fundamental waveform;the odd harmonics of cogging torque and electromagnetic torque are eliminated. Finally, the results of the new rotor step skewing method is verified by 3D finite element method (FEM) and further improved by embedding non-magnetic blocks in the middle of the stator and rotor.

关键词： Rotors Torque Forging Harmonic analysis Brushless motors Torque measurement AC motors

来源：评论

学校读者我要写书评

暂无评论

Design and analysis of a novel double-sided five-phase modular linear permanent magnet machine

Design and analysis of a novel double-sided five-phase modul...

引用

Annual Conference of Industrial Electronics Society

作者： keyu Guo Jing Zhao Xiangdong Liu Liu Yang Hao Chen Key laboratory for Intelligent Control & Decision of Complex Systems Beijing Institute of Technology Beijing China

In this paper, in order to replace a conventional electric linear actuator which is consist of rotary PM machine and ball screw, a novel double-sided five-phase modular linear permanent magnet synchronous machine (MLPMSM) is proposed and designed with the same volume. The basic structure of the machine is firstly described and the major dimensions of one module are then optimized to acquire the largest thrust force. Through these methods, the average force of the MLPMSM reaches 206N, which is 58.4% larger than the conventional linear actuator. After that, the 5 th order harmonic in thrust ripple is analyzed and diminished by adjusting the distance between slot openings of the module. As the result the 5 th order harmonic is diminished greatly by 57%.

关键词： Force Optimization Stator cores Actuators Harmonic analysis Iron

来源：评论

学校读者我要写书评

暂无评论

Adaptive optimal control for a class of uncertain systems with saturating actuators and external disturbance using integral reinforcement learning

Adaptive optimal control for a class of uncertain systems wi...

引用

Asian control Conference

作者： Jingang Zhao Minggang Gan Jie Chen Dongyang Hou Meng Zhang Yongqiang Bai State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing Institute of Technology Beijing

ISBN: (纸本)9781509015740;9781509015733

The problem of adaptive optimal control for a class of nonlinear uncertain systems with saturating actuators and external disturbance is investigated in this paper. Considering the saturating actuators, a non-quadratic cost function is adopted. The key of this optimal control problem is to find the solution to the Hamilton Jacobi Bellman equation (HJB). An online intergral reinforcement learning (IRL) algorithm based-Neural Network (NN) is given to approximate the solution. Unlike traditional integral reinforcement learning algorithms, data onto a period of time stored together with current data are used to update the neural network weights in place of persistence of excitation (PE) condition. This method overcomes the shortcomings of the PE condition which is not easy to be checked online. Finally, numerical examples are given to show the effectiveness of the proposed methods.

关键词： Optimal control Actuators Nonlinear systems Approximation algorithms Artificial neural networks System dynamics

来源：评论

学校读者我要写书评

暂无评论

Adaptive robust controller for electric cylinder with fast parameter estimation based on modified lugre model

Adaptive robust controller for electric cylinder with fast p...

引用

第36届中国控制会议

作者： Duo yang Li Jun Zheng Wang Ren Jian Hao Shou Kun Wang Wei Shen Key Laboratory of Intelligent Control and Decision of Complex Systems School of Automation Beijing Institute of Technology

In this paper,the adaptive robust control（ARC） algorithm is proposed for tracking control of the electric cylinder *** to the analysis of the working principle of the electric cylinder servo system,the model of the system is established on the modified Lugre friction model,and single observer is designed for calculating friction as *** the ARC controller and adaptive law are designed for on-line parameters estimation,frictional compensation and the suppression external *** the Lyapunov approach,the stability of this system can be obtained in this *** simulation result shows that ARC can suppresses external disturbances effectively and realize real-time online parameter estimation.

关键词： adaptive robust control Lugre model parameter estimation

来源：评论

学校读者我要写书评

暂无评论

A Modified System Model and its Application on SINS/GPS Integrated System

A Modified System Model and its Application on SINS/GPS Inte...

引用

IEEE International Conference on Cyber Technology in Automation, control, and intelligent Systems

作者： Xuan Xiao Xiang Guo Yuan Liang Chao Shi Songtian Shang Hong Hu School of Automation and State Key Laboratory of Complex System Intelligent Control and Decision Beijing Institute of Technology

ISBN: (纸本)9781538604915

Kalman filter has been extensively applied in vast areas. However, the performance of Kalman filter rests on the accuracy of prior information such as model construction. In the integrated system of Strapdown Inertial Navigation System (SINS)/Global Positioning System (GPS), the model construction is affected by a certain error sources. The most significant one is computational errors, which are caused by improper reference frame and the absence of true values. To solve the problem, this paper presents a modified system model which reduce the impact of computational errors by selecting computational frame as reference coordinate frame and removing all true values. Simulation results have demonstrated that modified system model effectively improves the performance of Kalman filter in SINS/GPS integrated system.

关键词： Kalman filters Systems modelling Integrated system strapdown inertial navigation system Error Sources Modified

来源：评论

学校读者我要写书评

暂无评论

Automatic design of hybrid optimizers based on particle swarm optimization and differential evolution 5

Automatic design of hybrid optimizers based on particle swar...

引用

5th International Workshop on Advanced Computational Intelligence and intelligent Informatics, IWACIII 2017

作者： Wang, Yipeng Xin, Bin School of Automation Beijing Institute of Technology Beijing100081 China Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing Institute of Technology Beijing100081 China Beijing Advanced Innovation Center for Intelligent Robots and Systems Beijing Institute of Technology Beijing100081 China

Hybridization is termed as an efficient strategy to improve the performance of many optimizers, and the design of efficient hybrids for difficult optimization problems remains a challenging field. In this study, an automatic method is proposed to generate various hybrid optimizers based on particle swarm optimization and differential evolution for a given problem. Based on the unified framework for hybridization proposed in our recent work, the proposed method can provide plenty of hybrid optimizers for a specific problem with given parent optimizers. Besides, an approach which can provide the unified representation of different kinds of hybridization levels is developed. Moreover, all the generated hybrids are evaluated on the CEC2017 benchmark problems, and the results of the statistic analysis and the Wilcoxon's rank-sum tests demonstrate that the hybrid optimizer utilizing the hybridization strategy performs obviously better than the others on the test functions.

关键词： Particle swarm optimization (PSO)

来源：评论

学校读者我要写书评

暂无评论

Small-scale intersection scan model for UGV in urban environment

Small-scale intersection scan model for UGV in urban environ...

引用

American control Conference (ACC)

作者： Yi Yang Hao Li Hao Zhu Ningyi Lyu Wenjie Song School of Automation and State Key Laboratory of Complex System Intelligent Control and Decision Beijing Institute of Technology Beijing Beijing CN School of Automation and State Key Laboratory of Complex System Intelligent Control and Decision Beijing Institute of Technology Beijing China

Intersection detection is a critical capacity for an Unmanned Ground Vehicle (UGV) to drive safely in structured urban environment. Large-scale intersections stamped on maps have plenty of features for detection while some unmapped small-scale urban intersections are hard to be identified. In this paper, we propose a novel intersection detection method conducted on the basis of Hidden Markov Model (HMM). This method is based on the intersection scan model to obtain the traversable directions to classify the intersection. The scan model is effective in dealing with both LIDAR and visual data. Combination of the scan model and the HMM can accurately estimate the traversable directions in consideration of both real-time and historic data. Results from simulations and real-world experiments have shown the functionality of the presented approach.

关键词： Hidden Markov models Roads Global Positioning System Three-dimensional displays Urban areas Laser radar Autonomous vehicles

来源：评论

学校读者我要写书评

暂无评论

Joint task management of sensor and weapon based on distributed management system

Joint task management of sensor and weapon based on distribu...

引用

Chinese control Conference (CCC)

作者： Zhang Mingyang Chen Chen Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing School of Automation Beijing Institute of Technology Beijing

ISBN: (纸本)9781538629185

In the modern war, many combat units combat collectively has become the main form. In the task management of the combat units, the calculation is large and the real-time requirement is high. To solve the problem better, a joint task management method of sensor and weapon based on distributed management system is proposed. Firstly, the distributed management system is constructed according to the target trajectory and the distribution of combat units. In the system, all the combat units are divided into several combinations, which only consist of a few combat units. As a result, the problem scale is reduced, and the real-time requirement of battlefield is met. Secondly, joint task management model of sensor and weapon is established. We consider time constraints and resource constraints to ensure the feasibility of the attack scheme, and consider the impact between sensor and weapon to achieve better combat effect. A discrete particle swarm optimization algorithm based on crossover strategy (CDPSO) is proposed to solve the model. The results show that the performance of the proposed algorithm is satisfactory in joint task management of sensor and weapon.

关键词： Weapons Distributed management Command and control systems Time factors Mathematical model Data processing Real-time systems

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：