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On the new results of global attractive set and positive invariant set of the Lorenz chaotic system and the applications to chaos control and synchronization

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Science in china(Series F) 2005年第3期48卷 304-321页

作者： LIAO Xiaoxin 1, 2, 3., FU Yuli 4 & XIE Shengli 4 1. Department of Control Science & Control Engineering, Huazhong university of Science & Technology, wuhan 43.074, china 2. {3. of Automation, wuhan university of Science & Technology, wuhan 43.070, china 3. school of information, central south university of economy, politics and law, wuhan 43.064, china 4. {3. of Electronics & information Engineering, south china university of Technology, Guangzhou 510640, china Correspondence should be addressed to Liao Xiaoxin (email: xiaoxin_liao@***) Department of Control Science & Control Engineering Huazhong University of Science & Technology Wuhan 430074 China

Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies the complex proofs of the two famous estimations presented by the Russian scholar Leonov. Our uniform formula can derive a series of the new estimations. Employing the idea of intersection in set theory, we extract a new Leonov formula-like estimation from the family of the estimations. With our method and the new estimation, one can confirm that there are no equilibrium, periodic solutions, almost periodic motions, wandering motions or other chaotic attractors outside the global attractive set. The Lorenz butterfly-like singular attractors are located in the global attractive set only. This result is applied to the chaos control and chaos synchronization. Some feedback control laws are obtained to guarantee that all the trajectories of the Lorenz systems track a periodic solution, or globally stabilize an unstable (or locally stable but not globally asymptotically stable) equilibrium. Further, some new global exponential chaos synchronization results are presented. Our new method and the new results are expected to be applied in real secure communication systems.

关键词： Lorenz chaotic system global attractive set positive invariant set globally exponential tracking globally exponential synchronization.

Relaxed resource advance reservation policy in grid computing

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The Journal of china Universities of Posts and Telecommunications 2009年第2期16卷 108-113页

作者： XIAO Peng HU Zhi-gang school of information Science and Engineering,central {3. university,Changsha 410083.china school of information Science and Engineering Central South University Changsha 410083 China

The advance reservation technique has been widely applied in many grid systems to provide end-to-end quality of service （QoS）. However, it will result in low resource utilization rate and high rejection rate when the reservation rate is high. To mitigate these negative effects brought about by advance reservation, a relaxed advance reservation policy is proposed, which allows accepting new reservation requests that overlap the existing reservations under certain conditions. Both the benefits and the risks of the proposed policy are presented theoretically. The experimental results show that the policy can achieve a higher resource utilization rate and lower rejection rate compared to the conventional reservation policy and backfilling technique. In addition, the policy shows better adaptation when the grid systems are in the presence of a high reservation rate.

关键词： grid computing advance reservation reservation violation computing economy

A novel method of systematic error compensation for a position and orientation system

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Progress in Natural Science:Materials International 2008年第8期18卷 953-963页

作者： Xiuxiao Yuan* school of Remote Sensing and information Engineering, wuhan {3., wuhan 43.079, china school of Remote Sensing and information Engineering Wuhan University Wuhan 430079 China

A novel method is introduced for self-calibration and elimination of systematic errors for a position and orientation system (POS). The method uses a combined bundle block adjustment with POS data (named the POS-supported bundle block adjustment) without a calibration field. On the basis of delivering strict observation equations for POS data, the specific scheme of compensating the translation and drift systematic errors in a POS is given, and a prototype system WuCAPS is developed. The effects of eliminating POS systematic errors using the POS-supported bundle block adjustment for different ground control conditions are tested using two sets of actual aerial photos. The first set was taken over a flat region in the suburbs of the city of Yingkou in china and tested at a scale of 1:2500. The second set was taken over a high mountainous region in the desert region of Xinjiang in china and tested at a scale of 1:3.,000. The empirical results verified that the POS systematic errors can be completely eliminated and the photo elements of exterior orientation obtained by the POS-supported bundle block adjustment can satisfy the requirements of aerial photogrammetric topographic mapping when four full ground control points (GCPs) are emplaced in the corners of the adjustment block for large-scale images of flat regions, but only one full GCP emplaced in the center of the adjustment block is needed for medium-small scale images of mountainous regions. This not only demonstrates the validity of the established mathematical model and the feasibility of the method proposed in this paper, but also avoids the use of a special calibration field. Therefore, it can simplify the existing POS operation rules and dramatically save on practical application costs, laying the theoretical foundation for widespread use of POS.

关键词： Position and orientation system (POS) Systematic error POS-supported bundle block adjustment Self-calibration Accuracy

Dynamic scheduling model of computing resource based on MAS cooperation mechanism

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Science in china(Series F) 2009年第8期52卷 1302-1320页

作者： JIANG WeiJin1,2, ZHANG LianMei3.& WANG Pu4 1 school of Computer and Electronic Engineering, Hunan university of Commerce, Changsha 410205, china 2 school of information Engineering, Xiangtan university, Xiangtan 411000, china 3.Electrical Engineering College, wuhan university, wuhan 43.072, china 4 school of Commerce, central {13. university, Changsha 410083. china school of Computer and Electronic Engineering Hunan University of Commerce school of information Engineering Xiangtan University Electrical Engineering College Wuhan University school of Commerce Central South University

Allocation of grid resources aims at improving resource utility and grid application performance. Currently, the algorithms proposed for this purpose do not fit well the autonomic, dynamic, distributive and heterogeneous features of the grid environment. According to MAS （multi-agent system） cooperation mechanism and market bidding game rules, a model of allocating allocation of grid resources based on market economy is introduced to reveal the relationship between supply and demand. This model can make good use of the studying and negotiating ability of consumers＇ agent and takes full consideration of the consumer＇s behavior, thus rendering the application and allocation of resource of the consumers rational and valid. In the meantime, the utility function of consumer is given; the existence and the uniqueness of Nash equilibrium point in the resource allocation game and the Nash equilibrium solution are discussed. A dynamic game algorithm of allocating grid resources is designed. Experimental results demonstrate that this algorithm diminishes effectively the unnecessary latency, improves significantly the smoothness of response time, the ratio of throughput and resource utility, thus rendering the supply and demand of the whole grid resource reasonable and the overall grid load balanceable.

关键词： multi-agent system (MAS) resource scheduling model evolutionary game cooperation mechanism utility function

On the design of compensator for quantization-caused input-output deviation

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Science china(information Sciences) 2011年第4期54卷 824-835页

作者： GUO YuQian,GUI WeiHua & YANG ChunHua school of information Science and Engineering,central {3. university,Changsha 410083.china school of information Science and Engineering Central South University

This paper considers the design of compensators for systems with quantized inputs in order to reduce the influence of *** systems with (vector) relative degrees,we propose a kind of compensators which can compensate for the accumulated output deviation completely caused by *** proposed compensators are capable of keeping the differences of the input-output responses between the systems with quantized inputs and the original systems without considering quantization within certain small *** show that the compensators in this paper are robust with respect to model uncertainties,disturbance and measurement noise and can significantly improve the input-output responses of systems with both input quantization and packet dropouts.

关键词： networked control systems quantization packet dropout I/O deviation compensation

Boron rings containing planar octa- and enneacoordinate cobalt, iron and nickel metal elements

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Science china Chemistry 2008年第7期51卷 607-613页

作者： LUO Qiong school of Chemistry and Chemical Engineering, central south {3., Changsha 410083. china school of Chemistry and Chemical Engineering Central South University Changsha China

For a series of boron rings with planar hyper-coordinate 8th group transition metal atoms, singlet 1FeB8-2, multiplet kFeB9n (n = -1, k = 1; n = 0, k = 2), singlet 1CoB8n(n = -1, +1, +3., multiplet kCoB9n (n = +1, k = 2; n = 0, k = 1) and singlet 1NiB9+, the geometry structures have been optimized to be local minima on corresponding potential hyper-surfaces. The electron structures are discussed by orbital analysis and the aromaticity is predicted by nucleus-independent chemical shifts calculation at both the B3.YP/6-3.1+G* and BP86/6-3.1+G* levels of theory, respectively. The results suggest that all these structures with high symmetry planar geometries are stable and have aromatic properties with six π valence electrons.

关键词： planar hyper-coordinate transition metal DFT

Training, simulation, restoration expert system for power grid

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Journal of central south university of Technology 2001年第1期8卷 69-73页

作者： LUO An,CHEN Qian (College of information Engineering, central south {3., Changsha 410083. china) College of information Engineering Central South University Changsha China

The paper introduces some technology for training, simulation, restoration expert system of power grid, the structure of the system including function composition, hardware and software composition are discussed, knowledge representation and the method to establish device graphical library for expert system are given, the fault setting and diagnosis for training and simulation as well as restoration technology with deep first searching arithmetic and heuristic inference are presented. The research provides a good base for developing the training, simulation, restoration system of power companies.

关键词： training simulation restoration expert system power grid

Characteristic atom arranging crystallogphy of alloy phases for Au-Cu system

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Science china(Technological Sciences) 2011年第6期54卷 1560-1567页

作者： XIE YouQing1,2,3.LIU XinBi1,2,3.PENG HongJian4,NIE YaoZhuang5,LI XiaoBo6 & LI YanFen1,2,3.1 school of Materials Science and Engineering,central south {3.,Changsha 410083.china 2 Powder Metallurgy Research Institute,central south {3.,Changsha 410083.china 3.State Key Laboratory of Powder Metallurgy,central south {3.,Changsha 410083.china 4 school of Chemistry and Chemical Engineering,central south {3.,Changsha 410083.china 5 school of Physical Science and Technique,central south {3.,Changsha,410083.china 6 College of Mechanical Engineering,Xiangtan {3.,Xiangtan 411105,china school of Materials Science and Engineering Central South University Powder Metallurgy Research Institute Central South University State Key Laboratory of Powder Metallurgy Central South University school of Chemistry and Chemical Engineering Centr

In this paper,it is pointed out that the descriptions of alloy phase structures are dependent on structural unit *** the systematic science of alloys(SSA),the alloy phase structures are described by means of the symmetry element sequence combining with characteristic atom *** is named the characteristic atom arranging structure,which can display the characteristic atoms at the lattice sites and the micro-inhomogeneity,besides the *** characteristic atom has its own characters:neighboring configuration,potential energy,volume and electronic *** micro-inhomogeneity of alloy phases can be described by concentrations and short-range ordered parameters of characteristic *** differences between the electronic structures of alloy phases and electronic structures of characteristic atoms in the alloy phases are also discussed.

关键词： systematic science of alloys Au-Cu system alloy phase structure micro-inhomogeneity

The feature study on the π and proton rapidity distributions at AGS, SPS and RHIC

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Science china(Physics,Mechanics & Astronomy) 2009年第2期52卷 198-206页

作者： FENG ShengQin1,2 & YUAN XianBao1,3.1 College of Science, china Three Gorges university, Yichang 443.02, china 2 {3. of Physics and Technology, wuhan university, wuhan 43.072, china 3.Institute of Particle Physics, central china Normal university, wuhan 43.070, china College of Science China Three Gorges University Yichang China school of Physics and Technology Wuhan University Wuhan China Institute of Particle Physics Central China Normal University Wuhan China

The features of nuclear stopping power and multi-hadron production systematically are studied by making an analysis of rapidity distributions of pion and proton at AGS, SPS and RHIC in this work. It is found that nuclear stopping power increases linearly with project rapidity yp at AGS and SPS, but that is not liner at RHIC. It is argued that the average rapidity loss is saturated at central rapidity region at RHIC. For pion distribution, it is found that the phase space of pion distribution distributes uniformly in the longitudinal direction,and a linear relationship of L with log s is given at AGS and SPS. Non-uniform flow model may explain the features of the distribution at AGS and SPS, but may not ex- plain those of at RHIC.

关键词： non-uniform flow model average rapidity loss baryon number density nuclear stopping power