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The 2012 International Conference on Advanced Material and Manufacturing science (ICAMMS 2012)

作者： YANG Tao HU Zhengdong YANG Libo Beijing Institute of Special Electromechanical Technology Science and Technology on Complex Systems Simulation Laboratory

This paper investigates a methodology for group coordination and cooperative control of satellites with the aim to achieve formation reconfiguration such as radius enlargement and phase angle *** proposed approach separates the control law into two distinct stages:planar movement control and orthogonal displacement *** in plane approach is based on a cyclic pursuit strategy,where satellite i pursues satellite i +*** phase angle adjustment,a control law that makes use of "beacon's guidance" is synthesized to maintain the circling centre *** the orthogonal direction,a linear feed back control on displacement and velocity is *** of two missions with low thrust are provided,which high light the over all effectiveness of the proposed approach.

关键词： Cyclic pursuit Beacon's guidance Satellite formation reconfiguration

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The simulation of cluster bombs' damage efficiency and analysis of damage factor

The simulation of cluster bombs' damage efficiency and analy...

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2014 International Conference on Future Communication technology and Engineering (FCTE 2014)

作者： S.Liu X.J.Zhao F.Zhao X.Wei W.F.Li Science and Technology on Complex Land Systems Simulation Laboratory Chinese Defense Science and Technology Information Centre

First, the paper emulated cluster bombs' random point of fall, the radius of damage of the bombs,drew the bombs' damage range, and counted the damage effect. The final damage efficiency of cluster bombs was calculated and the influence from each damage factor of the cluster bombs was studied through many random experiences. The method solved the tough problem of the precise calculation of damage efficiency, which was caused by the overlapped damage size.

关键词： The simulation of cluster bombs damage efficiency and analysis of damage factor simulation

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Improvement of a current measurement method with loop probes

Improvement of a current measurement method with loop probes

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Electromagnetic Launch technology

作者： Ronggang Cao Jun Li Beijing Institute of Technology Beijing China Science and Technology on Complex Land Systems Simulation Laboratory Beijing China

A new structure of B-dot probes for the rail-gun speed measurement is introduced, which combines several separate loops together. It is benefit for the digital data storage equipments to control its cost. In the past, each B-dot used single channel of the data recording equipment. If there were ten B-dot probes, we used ten channels for the probes to record data. However, it is no need to use so many channels. Because the core output waveforms of B-dot probes distribute in different time, several probes can be connected together to form one new probe. Extremely speaking, it is possible to use only one channel to record the data, and all the probes are combined into only one B-dot probe. The new B-dot probes' data was used to improve the current waveform measurement method with loop probes. Loop probes in the breech measure the magnetic field decided by the main current. If the current's position is fixed, the waveform of current can be easily calculated by the measured magnetic field. The armature's speed information is brought to reduce the influence of the nominal current position which is always changing. The experiment results show that it works fine to measure the current in low cost.

关键词： Probes Current measurement Magnetic field measurement Rails Magnetic fields Mathematical model Antenna measurements

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Study on methods based on Sobol indices method for analyzing sensitivity of army equipment effectiveness

Study on methods based on Sobol indices method for analyzing...

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2014 International Conference on simulation and Modeling Methodologies, Technologies and Applications (SMTA 2014)

作者： Zhiqiang Zhao Zhigang Wang Liu Yi Science and Technology on Complex land Systems Simulation Laboratory College of Mechaeronics Engineering and Automation National University of Defense Technology

Sensitivity analysis on weapons and equipment is the foundation for determining the priorities of development and construction of army weapons and equipment, constitutes the important contents of system optimization. In this paper, the applicability Sobol index method in the analysis of sensitivity of army equipment system effectiveness was explained, the model of Sobol index method theory was established, examples of sensitivity of army equipment system effectiveness was offered, and the applicability of this method was described through the comparisons of several common sensitivity indexes and the sensitivity index in Sobol index method.

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Comparisons of STRETCH meat grinders based on two different topologies of ICCOS

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Journal of Beijing Institute of technology 2013年第4期22卷 432-439页

作者：刘辉毕世华李军刘培柱陈阵 School of Aerospace Engineering Beijing Institute of Technology Science and Technology on Complex Land Systems Simulation Laboratory

Inductive energy storage systems （IES）require opening switches which are technically much more difficult to realize than closing switches. Institute of Advanced technology （ IAT ） puts forward a meat grinder with an inductive pulse power topology called slow transfer of energy through capacitive hybrid （STRETCH）. In this topology, an integrated gate-commutated thyristor （IGCT） is capable of breaking the charging currents on the order of 4 kA, and it may encounter difficulties in expanding to higher energy systems. German-French Institute of Saint Louis （ISL） has developed a high-power opening switch based on standard high-power thyristors by using their so-called inverse current commutation with semiconductor devices （ICCOS） countercurrent commutation principle. Two topologies of the STRETCH meat grinder with ICCOS are analyzed. And they are compared based on the voltage across the main switch, the current multiplication factor and other aspects by u- sing Matlab simulations. The advantages and disadvantages of the two topologies are shown through the comparisons. Therefore a more suitable topology can be chosen for realistic applications accord- ing to their performances.

关键词： inductive pulse power supplies STRETCH meat grinder IGCT inverse current commu-tation with semiconductor devices （ICCOS） comparisons

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Unified information modeling for achieving high-performance information sharing in the information grid

Unified information modeling for achieving high-performance ...

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2012 2nd International Conference on Management, Manufacturing and Materials Engineering, ICMMM 2012

作者： Zhang, Ying-chao Zhang, Jing Qin-Zhang, Yu Feng, Ye Wei, Li Zhi-Ming, Shen National Key Laboratory of Science and Technology on Complex Systems Simulation Beijing China

ISBN: (纸本)9783037855423

In this paper, an unified information description model ("UIDM" for short) is proposed to model information from multiple sources in the Information Grid uniformly. In the UIDM: 1) An unified information description language derived from the ODLI 3 is presented to describe information uniformly to resolve the information heterogeneity;2) A set of diagrammatized information modeling symbols are defined to model the information diagrammatically to illustrate the semantic relationships between information classes;3) An information capability model is advanced to model the capability of information from different information sources, based on which the high-performance global views for information sharing are to be constructed. © (2013) Trans Tech Publications, Switzerland.

关键词： Semantics

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Predictions of a supersonic jet-in-crossflow: Comparisons among CFD solvers and with experiment 32

Predictions of a supersonic jet-in-crossflow: Comparisons am...

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32nd AIAA Applied Aerodynamics Conference 2014

作者： DeSpirito, James Kennedy, Kevin D. Mikkelsen, Clark D. Chaplin, Ross A. U.S. Army Research Laboratory Aberdeen Proving Ground RDRL-WML-E Weapons and Materials Resarch Directorate MD 21005 United States U.S. Army Aviation and Missile Research Development and Engineering Center RDMR-SSM-A System Simulation and Development Directorate Redstone Arsenal AL 35898 United States Defence Science and Technology Laboratory Air and Weapons Systems Fareham Hampshire PO17 6AD United Kingdom

ISBN: (数字)9781624102882

ISBN: (纸本)9781624102882

A supersonic jet interaction flowfield with pressure ratios of 2.8-16.7 exhausting into subsonic and transonic crossflows (Mach 0.5-0.8) was simulated using computational fluid dynamics and compared to experimental particle image velocimetry data. Three independent studies using different Reynolds-averaged Navier-Stokes flow solvers and a variety of turbulence models were used to assess the accuracy level of the predicted downsteam flow physics of the jet interaction problem. Evaluation of the prediction of the downstream flow structure was made via comparisons of the three components of velcocity and turbulent kinetic energy. In general, the predicted jet interaction flowfield was highly sensitive to the turbulence model used, with performance of the turbulence model being dependent on the flow solver, and relatively insensitive to crossflow Mach number in the range investigated.

关键词： Turbulence models

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Metastable States and Wetting Transition of Submerged Superhydrophobic Structures

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Physical Review Letters 2014年第19期112卷 196101-196101页

作者： Pengyu Lv Yahui Xue Yipeng Shi Hao Lin Huiling Duan State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering Science College of Engineering Peking University Beijing 100871 China Key Laboratory of High Energy Density Physics Simulation Center for Applied Physics and Technology Peking University Beijing 100871 China Mechanical and Aerospace Engineering Rutgers The State University of New Jersey 98 Brett Road Piscataway New Jersey 08854 USA

Superhydrophobicity on structured surfaces is frequently achieved via the maintenance of liquid-air interfaces adjacent to the trapped air pockets. These interfaces, however, are subject to instabilities due to the Cassie-Baxter-to-Wenzel transition and total wetting. The current work examines in situ liquid-air interfaces on a submerged surface patterned with cylindrical micropores using confocal microscopy. Both the pinned Cassie-Baxter and depinned metastable states are directly observed and measured. The metastable state dynamically evolves, leading to a transition to the Wenzel state. This process is extensively quantified under different ambient pressure conditions, and the data are in good agreement with a diffusion-based model prediction. A similarity law along with a characteristic time scale is derived which governs the lifetime of the air pockets and which can be used to predict the longevity of underwater superhydrophobicity.

关键词： HYDROPHOBIC surfaces RESEARCH METASTABLE states WETTING LIQUID air PHYSICS research

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Markerless tracking algorithm based on 3D model for augmented reality system

Markerless tracking algorithm based on 3D model for augmente...

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3rd Sino-Foreign-Interchange Workshop on Intelligent science and Intelligent Data Engineering, IScIDE 2012

作者： Yao, Peng Chen, Can Weng, Dongdong School of Optoelectronics Beijing Institute of Technology Beijing China Science and Technology on Complex Land Systems Simulation Laboratory Beijing China

ISBN: (纸本)9783642366680

We present a markerless augmented reality(AR) system based on 3D model. First, the feature of environment was extracted using SIFT operator, then the method of stratified reconstruction was used to reconstruct the 3D scene, after that we constructed the database of prior knowledge using the KDTree. Finally, we tracked the 3D model based on these prior knowledge via feature matching and pose estimation in real time. Experimental results demonstrated that this method is sufficient for markerless tracking registration. With the prior knowledge, key frame selection problem can be avoided and the running speed is also increased. © Springer-Verlag 2013.

关键词： Augmented reality

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Statistic inference for inertial instrumentation error model using Bayesian network

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5th International Conference on Mechanical and Electrical technology, ICMET 2013

作者： Hu, Zheng Dong Zhang, Liu Xin Zhou, Fei Yue Li, Zhi Jun Science and Technology on Complex Land Systems Simulation Laboratory Beijing China Southwest Computer Co. Ltd Chongqing China

ISBN: (纸本)9783037858349

For the parameter estimation problem of inertial instrumentation error models, a Bayesian network is founded to fuse the calibration data and make error coefficients statistical inference in this paper. First the fundamental of Bayesian network is stated and then how to establish network for a typical case of inertial instrumentation error coefficients estimation is illustrated. Since the difficult high-dimension integral calculus for model parameter can be avoidable, WinBUGS software based on MCMC method is used for calculation and inference. The simulated results show that using Bayesian network to make statistical inference for inertial instrumentation error model is reasonable and effective. © (2013) Trans Tech Publications, Switzerland.

关键词： Bayesian networks

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