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A computer simulation of nucleation and growth of thin films

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Science China(Physics,Mechanics & Astronomy) 2004年第4期47卷 442-451页

作者： ZHENG Xiaoping1,ZHANG Peifeng2,HE Deyan2,LIU Jun2& MA Jiantai3.1. Key Laboratory of Opto-electronic technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong university, Lanzhou 73.070, China 2.{3. of Physical Science and technology, Lanzhou university, Lanzhou 73.000, China 3.{3. of Chemistry and Chemistry Engineering, Lanzhou university, Lanzhou 73.000, China 1. Key Laboratory of Opto-electronic technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University 730070 Lanzhou China 2. school of Physical Science and technology Lanzhou University 730000 Lanzhou China 3. school of Chemistry and Chemistry Engineering Lanzhou University 730000 Lanzhou China

A three-dimensional kinetic Monte Carlo technique has been developed for simulating the nucleation and growth of thin films. This model involves incident atom attachment, surface diffusion of the atoms on the growing surface and atom detachment from the growing surface. It takes some new effects into account, such as a significant improvement in calculation of activation energy for the atom diffusion, which renders the model more reasonable. In addition three optimum temperatures and the consistency of their dependence on deposition rate have been found out; the dependence of the surface roughness and relative density on the deposition rate has been discussed; and the approximation of freezing neighbour atoms and periodic boundary conditions has been applied.

关键词： Monte Carlo, thin film, nucleation, surface roughness, relative density.

Normalized Cut As Basic Tool For Remote Sensing Image

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Normalized Cut As Basic Tool For Remote Sensing Image

Dynamics of the generalized 3. + 1 function determined by its fractal images

2010 International Conference on Intelligent Computing and Integrated Systems

作者： WEM JING school of Computer and Control guilin university of electronic technology guilin 541004 China JIANG HUA school of Computer and Control guilin university of electronic technology guilin 541004 China WANG YUBIN school of Computer and Control guilin university of electronic technology guilin 541004 China

＜正＞Some remote sensing image segmentation algorithm can not make full use of local and global information and Normalized has NP-hard *** order to solve the problems,image can be described through the graph model and the Normalized cut can be used to cut graph for image *** algorithm is applied to create the initial segments,and then Normalized cut is used to segment among *** result shows that the method is effective.

关键词： remote sensing image image segmentation watershed graph theory normalized cut

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Progress in Natural Science:Materials International 2008年第2期18卷 217-223页

作者： Xingyuan Wang ,Xuejing Yu school of electronic & information Engineering,Dalian{3. of technology,Dalian 116024,China school of electronic & information Engineering Dalian University of Technology Dalian 116024 China

Two different complex maps were obtained by generalizing 3. + 1 function to the complex plane,and fractal images for these two complex maps were constructed by using escape time,stopping time and total stopping time arithmetic. The dynamics of the generalized 3. + 1 function based on the structural characteristics of the fractal images was studied. We found that: (1) the size and structure of the stable regions,stopping regions,total stopping regions,and divergent regions for the three types of fractal images depend on convergence rate of the map on the x and y axes. (2) The black stable regions constructed,respectively,by escape time and total stopping time are almost overlapped,demonstrating that 3. + 1 function converged steadily. (3. All of the three fractal images are symmetric to the real axis. The structures on the neighborhood of positive integer number are symmetric to a perpendicular line,which is corresponding to the point or its nearby points on the x axis. And the structures have complicated fractal structure characteristics. These findings indicate that the generalized 3. + 1 function on integer number and its neighborhood contains plentiful information in the complex plane.

关键词： Generalized 3. + 1 function Fractal images Dynamics

Secure, dependable and publicly verifiable distributed data storage in unattended wireless sensor networks

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Science China(information Sciences) 2010年第5期53卷 964-979页

作者： REN Wei 1 , REN Yi 2 & ZHANG Hui 3.1 school of Computer Science, China university of Geosciences (Wuhan), Wuhan 43.074, China 2 Department of information and{3. technology, university of Agder (UiA), Norway 3.Department of electronics, Politecnico di Torino (POLITO), Italy 1. school of Computer Science China University of Geosciences (Wuhan) Wuhan 430074 China2. Department of Information and Communication Technology University of Agder (UiA) Kristiansand Norway3. Department of Electronics Politecnico di Torino (POLITO) Torino Italy

In unattended wireless sensor networks (UWSNs), sensed data are stored locally or at designated nodes and further accessed by authorized collectors on demand. This paradigm is motivated by certain scenarios where historical or digest data (e.g., average temperature in a day), instead of real-time data, are of interest. The data are not instantly forwarded to a central sink upon sensing, thereby saving communication energy for transmission. Such a paradigm can also improve data survivability by making use of distributed data storage in cheap flash memory on nodes. However, the security and dependability of such data storage are critical for the future data accessibility in UWSNs. To address this issue, we propose a secure and dependable distributed storage scheme for UWSNs. Our scheme takes advantages of both secret sharing and Reed-Solomon code, which can achieve computational security and maintain low communication overhead in terms of shortened data dispersing size. We also propose a general coding method to publicly verify data integrity in a distributed manner, with low communication and storage overhead, and without the need of holding original data. The extensive analysis justifies that our scheme can provide secure, dependable and publicly verifiable distributed data storage in UWSNs even in the presence of node compromise and Byzantine failure.

关键词： secure storage dependability data integrity wireless sensor networks wireless network security

A 2.5GHz Low Phase Noise LC VCO for WLAN Applications in 0.18-μm CMOS technology

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A 2.5GHz Low Phase Noise LC VCO for WLAN Applications in 0.1...

Decentralized H-infinity state feedback control for discrete-time singular large-scale systems

2009 3.d IEEE International Symposium on Microwave,Antenna,Propagation and EMC Technologies for Wireless communications

作者： Ji-hai Duan 1 , Jian-ping Li 2 , Chao Qin 3.school of information & communication{3., GUET guilin, China

A 2.5GHz LC voltage controlled oscillator with low phase noise design and optimization is presented. The LC VCO is implemented in 0.18-μm CMOS technology and used for wireless local area network. The proposed VCO achieves phase noise of -128.7dBc/Hz at 1MHz offset, -105.4dBc/Hz at100KHz offset, 11% tuning range while consuming 3.A in 0.18V supply.

关键词： phase noise LC-tank accumulation MOS VCO

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控制理论与应用（英文版） 2010年第2期8卷 200-204页

作者： Songlin WO 1 , Yun ZOU 2 , Shengyuan XU 2 (1.school of Electrical and information Engineering, Jiangsu Teachers university of{3., Changzhou Jiangsu 213.01, China 2.school of Automation, Nanjing university of Science and{3., Nanjing Jiangsu 210094, China) school of Electrical and information Engineering Jiangsu Teachers University of Technology Changzhou Jiangsu China school of Automation Nanjing University of Science and Technology Nanjing Jiangsu China

The decentralized H-infinity control problem for discrete-time singular large-scale systems is considered. Based on the bounded real lemma of discrete-time singular systems, a sufficient condition for the existence of decentralized H-infinity controller for discrete-time singular large-scale systems is presented in terms of the solvability to a certain system of linear matrix inequalities by linear matrix inequality (LMI) approach, and the feasible solutions to the system of LMIs provide a parameterized representation of a set of decentralized H-infinity controller. The given example shows the application of the method.

关键词： Discrete-time singular large-scale system Linear matrix inequality (LMI) Decentralized H-infinity control

Study On communication Scheduling of Fieldbus

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Study On Communication Scheduling of Fieldbus

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

2009中国控制与决策会议

作者： Zhang Xiang-li information & communication College,guilin{3. of electronic technology,541004 guilin,Guangxi,P.R.China

＜正＞The communication tasks of fieldbus system often include the information transfer among the field devices. However,fieldbus is not an absolute system,which is a component of entire ***,as to fieldbus scheduling,not only the communication tasks of fieldbus but also the restrains from the other tasks in the system should be *** this paper,a dynamic fieldbus scheduling algorithm is used to cope with the dynamic scheduling of the task system including cyclic real-time tasks,acyclic real-time tasks,non-real-time tasks and time slot tasks under distributed multi-processor *** model of the task system is presented and the algorithm is *** last,a real-time communication scheduling of computer numerical control（CNC） fieldbus system is illustrated to apply the algorithm,and the time and space cost of this algorithm is analyzed.

关键词： Fieldbus communication Task Scheduling Multi-processor

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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 technology 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

CAD/CAE OF THE WORKING CHARACTERISTICS OF A NEW TYPE OF FLUID COUPLING SHOCK ABSORBER

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Chinese Journal of Mechanical Engineering 2002年第3期15卷 222-227页

作者： Yang Ping Zhong Yifang Zhou Jischool of Mechanical Science and Engineering, Huazhong university of Science and technology,Wuhan 43.074, ChinaLiu Yong{3. Institute of electronic technology *** school of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

For purpose of simulation of the working characteristics of a new type offluid coupling shock absorber for vibration protection of sensitive equipment, a physical model ispresented by analyzing the internal fluid dynamic phenomenon with respect to the coupling shockabsorber and implemented in MATLAB software package. Using the model it is possible to evaluate theimportance of different factors for design of the shock absorber. In the meantime, the key-modelmachine is designed for coupling dynamic test. Comparisons with experimental results confirm thevalidity of the model. So the CAD/CAE software has been developed in MATLAB for design andexperimental test of the new coupling shock absorber.

关键词： Fluid coupling shock absorber Working characteristics Model Simulation