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The Decentralized Robust control of Hydroelectric Units on AGC Operating Condition

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The Decentralized Robust Control of Hydroelectric Units on A...

Chitosan——L-Lactic Acid Scaffold for the Regeneration of Peripheral Nerve and Its NGF Release Properties

2.09中国控制与决策会议

作者： Luo Nanhua~1,Yang Xiaoju~1,Wang Wei~2.1.Department of Energy Source,Changchun Institute of technology,Changchun,130012.2.research center of information and control,{2.,dalian,11602.

＜正＞Aiming at the unmatched interconnections and uncertainties of hydroelectric units on the automatic generation control operating condition,a new decentralized robust control method is present in this *** two-step method,the advantages of interconnections can be made better use and unmatched uncertainties are considered,which usually can not be studied in the problem of decentralized robust *** using the proposed method,all hydropower units can be controlled in each optimized control strategy on the AGC operation *** results show that the interconnection disturbance among the hydroelectric units of cascade power plants can be effectively solved by proposed method.

关键词： Automatic Generation control(AGC) Hydroelectric Units Interconnection Unmatched Decentralized Robust control

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Journal of Wuhan university of technology(Materials Science) 2009年第6期24卷 961-964页

作者：徐海星 Department of Pharmaceutical Engineering School of Chemical EngineeringWuhan University of Technology

Chitosan—L-lactic acid composite scaffold for the regeneration of peripheral nerve is obtained by grafting L-lactic acid onto the amino groups in chitosan with combined vacuum freezer drier. The composite scaffold was characterized by ATR-FTIR and SEM. The scaffold has a better graft efficiency and has a dense inner layer and a loose outer layer with porous structure, and the pore size is about 100 μ*** NGF release properties of the scaffold were investigated. The experimental results showed that, at the 1st day, 15.2.ng of NGF on average was released from the scaffold. From day 2.to day 10, the release rate obviously slowed down and 1.64 ng of NGF was released on average every day. After 10 days, the release rate was slower and 10.3 ng of NGF was released on average every day. After 60 days, NGF could also maintained a certain concentration. These properties show that the scaffold is a better carrier for NGF which can be more advantageous to the regeneration of the damaged peripheral nerve. As a result, this composite scaffold would be an ideal candidate for the regeneration of damaged peripheral nerve.

关键词： chitosan L-lactic acid peripheral nerve NGF release properties

Spray and forward:Efficient routing based on the Markov location prediction model for DTNs

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Science China(information Sciences) 2012年第2期55卷 433-440页

作者： DANG Fei1,YANG XiaoLong1,2.& LONG KePing2.1 research center for Optical Internet and Mobile {2. Networks(COIMIN),university of Electronic Science and technology of China,Chengdu 611731,China 2.School of Computer and Communications Engineering,university of Science and technology Beijing,Beijing 100083,China 1. research center for Optical Internet and Mobile {2. Networks (COIMIN) University of Electronic Science and Technology of China Chengdu 611731 China2. School of Computer and Communications Engineering University of Science and Technology Beijing Beijing 100083 China

Typical delay tolerant networks(DTNs)often suffer from long and variable delays,frequent connectivity disruptions,and high bit error *** DTNs,the design of an efficient routing algorithm is one of the key *** existing methods improve the accessibility probability of the data transmission by transmitting many copies of the packet to the network,but they may cause a high network *** address the tradeoff between a successful delivery ratio and the network overhead,we propose a DTN routing algorithm based on the Markov location prediction model,called the spray and forward routing algorithm(SFR).Based on historical information of the nodes,the algorithm uses the second-order Markov forecasting mechanism to predict the location of the destination node,and then forwards the data by greedy routing,which reduces the copies of packets by spraying the packets in a particular *** contrast to a fixed mode where a successful-delivery ratio and routing overhead are contradictory,a hybrid strategy with multi-copy forwarding is able to reduce the copies of the packets efficiently and at the same time maintain an acceptable successful-delivery *** simulation results show that the proposed SFR is efficient enough to provide better network performance than the spray and wait routing algorithm,in scenarios with sparse node density and fast mobility of the nodes.

关键词： delay tolerant networks spray and forward Markov position prediction routing algorithm

A formal model of fair exchange protocols

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Science in China(Series F) 2005年第4期48卷 499-512页

作者： QING Sihan1,2.3 & LI Gaicheng1,2.3 1. Engineering research center for {2. Security technology, Institute of Software, Chinese Aca- demy of Sciences, Beijing 100080, China 2. Beijing Zhongke Ansheng Corporation of {2. technology, Beijing 100080, China 3. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 1. Engineering research center for {2. Security technology Institute of Software Chinese Academy of Sciences 100080 Beijing China 2. Beijing Zhongke Ansheng Corporation of information technology 100080 Beijing China 3. Graduate School of the Chinese Academy of Sciences 100039 Beijing China

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

Channel-aware and queue-aware joint-layer resource optimization for cognitive radio networks

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Science China(information Sciences) 2010年第12期53卷 2576-2583页

作者： GUO KunQi 1,2.SUN LiXin 1,LI Yong 2.& JIA ShiLou 3 1 School of Computer Science and Telecommunication Engineering,Jiangsu university,Zhenjiang 2.2.13,China 2.research {2. for Wireless Communication,Shanghai Institute of Microsystem and information technology,Chinese Academy of Sciences,Shanghai 2.0050,China 3 Communication research {2.,Harbin Institute of technology,Harbin 150001,China 1. School of Computer Science and Telecommunication Engineering Jiangsu University Zhenjiang 212013 China2. Research Center for Wireless Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China3. Communication Research Center Harbin Institute of Technology Harbin 150001 China

An optimization model is derived to maximize the utilization efficiency of the idle channels of primary users(PU) in cognitive radio *** the optimization model,Lyapunov optimization method is used to allocate the idle channels of PU to secondary user(SU) most *** time distribution of the idle channels of PU is predicted by a low-pass time *** algorithm is proposed to implement the optimization *** algorithm is efficient because of using a greedy selection *** efficiency of the algorithm is demonstrated by mathematic analyses and simulation results.

关键词： cognitive radio networks Lyapunov optimization resource utilization primary user secondary user

Electric-stimulus rate encoding algorithm of Mandarin tonal information in cochlear implant

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Progress in Natural Science:Materials International 2006年第12期16卷 1315-1321页

作者： GUAN Tian~1, GONG Qin~1 and YE Datian~2.*(1. Department of Biomedical Engineering, Tsinghua university, Beijing 100084, China 2. research {2. of Biomedical Engineering, Graduate School at Shenzhen, Tsinghua university, Shenzhen 518055, China) [a]Department of Biomedical Engineering Tsinghua University Beijing China [b]research center of Biomedical Engineering Graduate School at Shenzhen Tsinghua University Shenzhen China

The modern multi-channel cochlear implants usually extract and encode the temporal envelope cues. This kind of algorithms can hardly satisfy the users who speak tonal languages, such as Mandarin. Many studies have tried to enhance the recognition ability of Mandarin through encoding tonal information and made suggestions to frequency-modulate the fixed pulse-rate carrier with the extracted tonal information based on the rate-pitch theory in electric hearing. However, how to encode and deliver the tonal information such as F_0by changing electric-stimulus rate has not got further study in clinical electric-stimulus mode. The present paper focuses on this matter by piecewise calculating the appreciable electric-stimulus rates. Then an electric-stimulus encoding algorithm of Mandarin tone is brought forward and testified through acoustic simulations. Such conclusion can be drawn that this algorithm of electric-stimulus rate could convey tonal information well and help to enhance the Mandarin speech recognition ability.

关键词： cochlear implant tone fundamental frequency electric-stimulus rate.

Molecular dynamics simulation study on zwitterionic structure to maintain the normal conformations of Glutathione

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Science China Chemistry 2007年第5期50卷 660-664页

作者： YAN Han1, ZHU HaoMiao2.& SHEN Jian1,2.1 Jiangsu research center of Surface and Interface Chemical Engineering and {2., Nanjing university, Nanjing 2.0093, China 2.Jiangsu Engineering research center for Bio-medical function Materials, Nanjing Normal university, Nanjing 2.0097, China Jiangsu research center of Surface and Interface Chemical Engineering and{2. Nanjing UniversityNanjing 210093China Jiangsu Engineering research center forBio-medical function Materials Nanjing Normal UniversityNanjing 210097China

Molecular dynamics simulations were applied to normal conformational Glutathione (GSH) and GSH over zwitterionic and hydrophobic surfaces respectively. Conformational analysis of GSH during the simulation time on RMSD, conformational flexibility and dihedral distribution were performed. The re- sults showed that zwitterionic structure maintains the normal conformations of GSH to a better extent, which should be a first good proof of the hypothesis of "maintain of normal structure".

关键词： protein-surface interactions, molecular dynamics simulation, zwitterionic structure, Glutathione, conformational changes, antithrombotic material

Nano-scale Interfacial Friction Behavior between Two Kinds of Materials in MEMS Based on Molecular Dynamics Simulations

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Journal of Wuhan university of technology(Materials Science) 2006年第4期21卷 173-176页

作者：杨平 research center of Micro-Nano Science and {2. Jiangsu University Zhenjiang 212013ChinaResearch Center of Advanced Design & Manufacturing Guilin Institute of Electronic Technology Guilin 541004 China

The aim of this article was to provide a systematic method to perform molecular dynamics simulotion or evaluation for nano-scale interfacial friction behavior between two kinds of materials in MEMS design. Friction is an important factor affecting the performance and reliability of MEMS. The model of the nano-scale interracial friction behavior between two kinds of materials was presented based on the Newton＇ s equations of motion. The Morse potential function was selected for the model. The improved Verlet algorithm was employed to resolve the model, the atom trajectories and the law of the interfacial friction behavior. Comparisons with experimental data in other paper confirm the validity of the model. Using the model it is possible to simulate or evaluate the importance of different factors for designing of the nano-scale interfacial friction behavior between two kinds of materials in MEMS.

关键词： molecular dynamics simulation interfacial friction nano-scale friction MEMS

Integrative inversion of land surface component temperature

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Science China Earth Sciences 2005年第11期48卷 2011-2019页

作者： FAN Wenjie1 & XU Xiru1,2.1. Institute of Remote Sensing and Geographical information System, Peking university, Beijing 100871, China 2. {2. of Remote Sensing and GIS of Beijing Normal university, Beijing 100875, China 1. Institute of Remote Sensing and Geographical information System Peking University 100871 Beijing China 2. center of Remote Sensing and GIS of Beijing Normal university 100875 Beijing China

In this paper, the row winter wheat was selected as the example to study the com-ponent temperature inversion method of land surface target in detail. The result showed that the structural pattern of row crop can affect the inversion precision of component temperature evi-dently. Choosing appropriate structural pattern of row crop can improve the inversion precision significantly. The iterative method combining inverse matrix was a stable method that was fit for inversing component temperature of land surface target. The result of simulation and field ex-periment showed that the integrative method could remarkably improve the inversion accuracy of the lighted soil surface temperature and the top layer canopy temperature, and enhance inver-sion stability of components temperature. Just two parameters were sufficient for accurate at-mospheric correction of multi-angle and multi-spectral thermal infrared data: atmospheric trans-mittance and the atmospheric upwelling radiance. If the atmospheric parameters and component temperature can be inversed synchronously, the really and truly accurate atmospheric correction can be achieved. The validation using ATSRII data showed that the method was useful.

关键词： components temperature, inverse pattern, atmospheric correction