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Composition Operator From Qk Space to Bloch-type Space

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Composition Operator From Qk Space to Bloch-type Space

RESPONSE’S ANALYSIS OF NONLINEAR MAGNETIC LEVITATION CONTROL SYSTEM TO RANDOM VIBRATION

不确定性——新内涵、新魅力、新机遇、新挑战——第十届中国不确定系统年会暨第十四届中国青年信息与管理学者大会

作者： Guangrong Liu,Jia Liu science of college,air force engineering university,Xi'an 710051,China

Necessary and sufficient conditions are given for a composition operator Cf = fo（?） to be bounded and compact from Q space to Bloch-type space.

关键词： Bloch-type spaces Qk space composition operator

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RESPONSE’S ANALYSIS OF NONLINEAR MAGNETIC LEVITATION CONTRO...

The Research on Navigation and Position Augmentation System Based Cloud Computing

The Second International Conference on Dynamics Vibration and Control

作者： Hong Yao Xueren Li and Guangjun Zhang Math and Physics Department science college of air force engineering university Xi ’an 710049 China

＜正＞Based on the theory of nonlinear control system, there is much phenomenon in the nonlinear control system that will never appear in the linear system, that is so called essential nonlinear phenomenon, such as leap, self-oscillation, sub resonance and high resonance, chaos and so on. In this case, if linear system were used to predict random response of nonlinear system, usually, incorrect conclusions will be educed. I have to note, although there are many methods to predict random response of nonlinear control system

关键词： magnetic levitation random vibration response control system

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The Research on Navigation and Position Augmentation System ...

第三届中国卫星导航学术年会

作者： Lu Hu*,SHEN Shuwei,JI ZHengzhou,WANG Congmin The science college,air force engineering university,XI’AN, China.P.R

This paper introduced cloud computing into navigation and positioning field to improve the capability of current system. The basic principle and network topology, which based on navigation and positioning cloud platform technology, were presented. Then the cloud computing was implemented in the wide-area DGNSS to broadcast the navigation augmentation information on real time. The cloud navigation based wide area differential augmentation （CNBW） system was analyzed in detail, and presented the network topology and mathematical model under cloud computing model. The performance of CNBW system is analyzed, the results show that CNBW allowed real time communication and the throughput of server was lower than other network systems, so it could meet the need of applications for large scale and real time broadcasting for the augmentation messages of GNSS through internet.

关键词： Cloud Computing GNSS augmentation information Real time broadcasting

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基于三点法的地空导弹攻击过程可视化仿真

系统仿真学报 2009年第22期21卷 7172-7175页

作者：杨宇袁修久王胜勇刘欣空军工程大学理学院西安710051

地空导弹攻击过程可视化仿真包括数学模型的建立和可视化场景的实现,精确的数学模型是场景高度逼真的前提。分析了地空导弹在空气动力、发动机推力和重力作用下的受力情况,建立了在三点法引导时导弹攻击过程的运动方程组,并给出了目标... 详细信息

地空导弹攻击过程可视化仿真包括数学模型的建立和可视化场景的实现,精确的数学模型是场景高度逼真的前提。分析了地空导弹在空气动力、发动机推力和重力作用下的受力情况,建立了在三点法引导时导弹攻击过程的运动方程组,并给出了目标在蛇形机动时导弹相应的三维弹道曲线。最后运用OpenGL图形库,研究了天空、地面以及导弹飞行尾焰和爆炸场景等特殊效果的生成方法,实现了导弹攻击过程的可视化仿真,较精确地再现了三点法引导时地空导弹的飞行过程。

关键词：可视化仿真三点法导弹运动方程组三维弹道

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推广的三维L-系统及在树木模拟中的应用

系统仿真学报 2011年第11期23卷 2308-2311页

作者：袁修久王胜勇刘欣赵学军空军工程大学理学院西安710051

L-系统是植物模拟的重要方法之一。然而用L-系统模拟既有弯曲又有扭曲的枝条,需要大量的产生式,并且很难提炼出这些产生式。通过把空间曲线理论同L-系统相结合,将L-系统的表示图形的字符联系了曲率函数和挠率函数,并且对L-系统中的字符... 详细信息

L-系统是植物模拟的重要方法之一。然而用L-系统模拟既有弯曲又有扭曲的枝条,需要大量的产生式,并且很难提炼出这些产生式。通过把空间曲线理论同L-系统相结合,将L-系统的表示图形的字符联系了曲率函数和挠率函数,并且对L-系统中的字符进行了新的龟解释,得到了三维函数L-系统。使用三维函数L-系统绘制既有弯曲又有扭曲的枝条的植物时,L-系统简洁,参数解释自然,同时在编程时,容易控制枝条的长度。实验结果表明,通过调整函数L-系统中的曲率函数和挠率函数可以得到拓扑结构相同但形态差异较大的树。

关键词：三维植物模拟弯曲枝条 L-系统空间曲线理论

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连通的开口和闭口谐振环构成的磁超材料设计

物理学报 2011年第8期60卷 209-215页

作者：陈春晖屈绍波王甲富马华徐卓何花空军工程大学理学院西安710051 西安交通大学电子陶瓷与器件教育部重点实验室西安710049

在已有的磁超材料和左手材料结构中,负等效磁导率主要通过开口谐振环、平行短金属线对或者它们的变形结构来实现.这些结构要求入射电磁波的电场方向平行于基板.针对这一特点,利用将开口和闭口的谐振环相连通的思想,设计出了入射电磁波... 详细信息

在已有的磁超材料和左手材料结构中,负等效磁导率主要通过开口谐振环、平行短金属线对或者它们的变形结构来实现.这些结构要求入射电磁波的电场方向平行于基板.针对这一特点,利用将开口和闭口的谐振环相连通的思想,设计出了入射电磁波的电场方向垂直于基板型的三维磁超材料,并予以实验验证.该对称结构中金属线线宽的变化对磁谐振频率影响很小,有利于实际的加工和应用.同时,该结构对于设计三维以及具有极化无关、均匀各向同性等特点的磁超材料和左手材料具有参考价值.

关键词：磁超材料谐振环电场方向

MHD Flow Control of Oblique Shock Waves Around Ramps in Low-temperature Supersonic Flows

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Chinese Journal of Aeronautics 2010年第1期23卷 22-32页

作者： Su Changbing,Li Yinghong,Cheng Bangqin,Wang Jian,Cao Jun,Li Yiwen engineering college,air force engineering university,Xi’an 710038,China engineering college Air Force Engineering University Xi'an 710038 China

This article is devoted to experimental study on the control of the oblique shock wave around the ramp in a low-temperature supersonic flow by means of the magnetohydrodynamic （MHD） flow control technique. The purpose of the experiments is to take advantage of MHD interaction to weaken the oblique shock wave strength by changing the boundary flow characteristics around the ramp. Plasma columns are generated by pulsed direct current （ DC ） discharge, the magnetic fields are generated by Nd-Fe-B rare-earth permanent magnets and the oblique shock waves in supersonic flow are generated by the ramp. The Lorentz body force effect of MHD interaction on the plasma-induced airflow velocity is verified through particle image velocimetry（PIV）measurements. The experimental results from the supersonic wind tunnel indicate that the MHD flow control can drastically change the flow characteristics of the airflow around the ramp and decrease the ratio of the Pitot pressure after shock wave to that before it by up to 19.66% ,which leads to the decline in oblique shock wave strength. The oblique shock waves in front of the ramp move upstream by the action of the Lorentz body force. The discharge characteristics are analyzed and the MHD interaction time and consumed energy are determined with the help of the pulsed DC discharge images. The interaction parameter corresponding to the boundary layer velocity can reach 1.3 from the momentum conservation equation. The velocity of the plasma column in the magnetic field is much faster than that in the absence of magnetic field force. The plasma can strike the neutral gas molecules to transfer momentum and accelerate the flow around the ramp.

关键词： aerospace propulsion system magnetohydrodynamic flow control plasma shock wave

AERODYNAMIC CHARACTERISTICS ABOUT MINING DUMP TRUCK AND THE IMPROVEMENT OF HEAD SHAPE

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Journal of Hydrodynamics 2008年第6期20卷 713-718页

作者： WEI Xiu-ling WANG Guo-qiang FENG Su-li college of Mechanical science and engineering Jilin University Changchun 130022 China Department of Aeronautic Mechanical engineering Aviation University of Air force Changchun 130022 China Fundamental science Department Armor Technique Institute Changchun 130117 China

The external flow field around a certain mining dump truck was simulated. The airflow structure and the aerodynamic drag were discussed, and the relationship between airflow characteristics and aerodynamic drag were obtained. In order to solve the problem of head shape of the truck, three scenarios including edge rounding, installing splitter planes and their combination were put forward to improve the head shape through numerical simulation and analysis. The model and method were selected to be three dimensional and time-independent. The Reynolds-averaged Navier-Stokes equations were solved using the finite volume method. The RNG k-ε model was chosen for the closure of the turbulent quantities. The results show that the third scenario is the best one, because of its aerodynamic characteristics being better than those of unimproved model.

关键词： dump truck external flow field numerical simulation

STUDY ON SHIFT SCHEDULE AND SIMULATION OF AUTOMATIC TRANSMISSION

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Chinese Journal of Mechanical engineering 2001年第3期14卷 250-253页

作者： Gong Jie,Zhao Dingxuan (college of Mechanical science and engineering ,Jilin university) 吉林大学机械科学与工程学院吉林长春

From the point of view of saving energy, a new shift schedule and auto-controlling strategy for automatic transmission are proposed. In order to verify this shift schedule, a simulation program using a software package of Matlab/ Simulink is developed. The simulation results show the shift schedule is correct. This shift schedule has enriched the theory of vehicle automatic maneuvering and will improve the efficiency of hydrodynanic drive system of the vehicle.

关键词： engineering vehicle Automatic transmission Shift schedule Simulation Saving energy