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Review of prediction for thermal contact resistance

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Science china(Technological Sciences) 2010年第7期53卷 1798-1808页

作者： WANG AnLiang1 & ZHAO JianFeng2 1 School of Astronautics, Beihang University, beijing 100191, china china academy of space technology, beijing 100094, china 1. School of Astronautics Beihang University Beijing 100191 China2. China Academy of Space Technology Beijing 100094 China

Theoretical prediction research on thermal contact resistance is reviewed in this paper. In general, modeling or simulating the thermal contact resistance involves several aspects, including the descriptions of surface topography, the analysis of micro mechanical deformation, and the thermal models. Some key problems are proposed for accurately predicting the thermal resistance of two solid contact surfaces. We provide a perspective on further promising research, which would be beneficial to understanding mechanisms and engineering applications of the thermal contact resistance in heat transport phenomena.

关键词： thermal contact resistance thermal contact conductance surface topography deformation assumption prediction model numerical simulation

COMBINATION OF CFD AND CSD PACKAGES FOR FLUID-STRUCTURE INTERACTION

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Journal of Hydrodynamics 2008年第6期20卷 756-761页

作者： WANG Yi-wei LIN Yong-wen Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China china academy of space technology Beijing 100094 China

In this article the UDF script file in the Fluent software was rewritten as the ＂connecting file＂ for the Fluent and the ANSYS/ABAQUS in order that the joined file can be used to do aero-elastic computations. In this way the fluid field is computed by solving the Navier-Stokes equations and the structure movement is integrated by the dynamics directly. An analysis of the computed results shows that this coupled method designed for simulating aero-elastic systems is workable and can be used for the other fluid-structure interaction problems.

关键词： CFD/CSD fluid-structure interaction aero-elasticity fluttering

Fractional Fourier domain equalization for single carrier broadband wireless systems

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Science china(Information Sciences) 2012年第10期55卷 2257-2268页

作者： HUANG KeWu 1,2,TAO Ran 1 & WANG Yue 1 1 Department of Electronic Engineering,beijing Institute of technology,beijing 100081,china 2 Institute of Manned space System Engineering,china academy of space technology,beijing 100094,china 1. Department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China2. Institute of Manned Space System Engineering China Academy of Space Technology Beijing 100094 China

In this paper,a novel single carrier equalization approach in the fractional Fourier domain(FRFD) is *** can remove all the inter-symbol interference(ISI) and avoid the considerable noise enhancement of the frequency domain-zero forcing(FD-ZF) *** the fractional Fourier transform makes a chirp spread,the impulse response of the deep fading channel may be flattened in some orders of the FRFD while it would be greatly attenuated in the *** searching for an optimal order under certain criterion,we take advantages of the ZF algorithm to mitigate the effects of the ISI *** approach can overcome the contradiction between the ISI mitigation and the noise enhancement of the FD-ZF *** analysis and simulation results show that the proposed FRFD-ZF equalizer can achieve a significant performance and have the same computation cost O(N log N) as the conventional FD linear equalizer,especially in the frequencyselective deep-fading channels.

关键词： fractional Fourier transform single carrier systems zero-forcing equalizer frequency domain linear equalizer

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地球静止卫星位置自主确定方法与仿真研究

系统仿真学报 2008年第18期20卷 4798-4801,4805页

作者：杨慧中国空间技术研究院北京100094

给出了利用星敏感器测量信息自主确定地球静止卫星位置的方法,利用不同精度的星敏感器测量数据和不同控制精度的卫星姿态测量数据,可以直接计算卫星位置。同时又对测量数据应用卡尔曼滤波进行卫星位置计算仿真,比较两种处理结果的精度... 详细信息

给出了利用星敏感器测量信息自主确定地球静止卫星位置的方法,利用不同精度的星敏感器测量数据和不同控制精度的卫星姿态测量数据,可以直接计算卫星位置。同时又对测量数据应用卡尔曼滤波进行卫星位置计算仿真,比较两种处理结果的精度。仿真结果表明,提出的方法可以实时自主获取静止卫星的轨道位置,满足静止卫星定点的不同精度需求。

关键词：静止卫星自主位置确定滤波仿真

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基于STK二次开发的全球导航星座部署研究

系统仿真学报 2008年第23期20卷 6560-6562页

作者：胡伟王劼中国空间技术研究院总体部北京100094

利用C++进行二次开发,驱动STK Connect链接覆盖模块仿真研究全球星座部署策略问题,最终确定出优先覆盖我国境内的星座部署顺序。整个仿真过程分为三个阶段:链接准备和场景建立阶段、部署策略的设计和选取阶段、数据处理和评估阶段。针... 详细信息

利用C++进行二次开发,驱动STK Connect链接覆盖模块仿真研究全球星座部署策略问题,最终确定出优先覆盖我国境内的星座部署顺序。整个仿真过程分为三个阶段:链接准备和场景建立阶段、部署策略的设计和选取阶段、数据处理和评估阶段。针对不同的部署目标选取适当的评估指标,实现了不同的卫星部署策略择优。

关键词：卫星导航系统星座部署 STK 二次开发

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平流层飞艇高度方向稳态运动建模与特性分析

系统仿真学报 2008年第24期20卷 6830-6833,6838页

作者：郑威王文隽姚伟吴志红李勇中国空间技术研究院研究发展中心北京100094

平流层飞艇高度方向稳态运动的特性和规律是飞艇运行高度预测和控制、内环境控制和系统设计等研究工作的重要基础之一,为全面阐明该特性与规律,建立了平流层飞艇在高度方向上的运动数学模型,计算得到了在高度方向稳态运动条件下艇内温... 详细信息

平流层飞艇高度方向稳态运动的特性和规律是飞艇运行高度预测和控制、内环境控制和系统设计等研究工作的重要基础之一,为全面阐明该特性与规律,建立了平流层飞艇在高度方向上的运动数学模型,计算得到了在高度方向稳态运动条件下艇内温度、压力与飞艇运行高度之间的关系,并对平流层飞艇在高度方向运动的稳态特性进行了详细分析。最后,分析结论提出了实现平流层飞艇在高度方向稳定安全运行需要满足的技术要求。

关键词：平流层飞艇建模稳态运动特性分析

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载人深空飞行返回再入模式仿真研究

系统仿真学报 2009年第16期21卷 4958-4960页

作者：闵学龙潘腾郭海林中国空间技术研究院总体部北京100094

建立了用于研究载人深空飞行返回再入模式问题的平面动力学模型,进行了基于弹道式和半弹道式模式再入的轨道仿真,分析比较了相同参数条件下两种再入模式的轨道动力学仿真结果,得出了载人深空飞行返回应采用半弹道式模式再入的结论,为进... 详细信息

建立了用于研究载人深空飞行返回再入模式问题的平面动力学模型,进行了基于弹道式和半弹道式模式再入的轨道仿真,分析比较了相同参数条件下两种再入模式的轨道动力学仿真结果,得出了载人深空飞行返回应采用半弹道式模式再入的结论,为进一步研究载人深空飞行返回再入策略和轨道优化设计提供了条件。

关键词：载人深空飞行再入模式再入轨迹仿真

R-D Optimized Image Coding with S-WT Based on Dyadic Rectangular Tiling

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R-D Optimized Image Coding with S-WT Based on Dyadic Rectang...

Onboard Laser Time Transfer Payload and Its Application for Chinese Navigation Satellites

The Seventh International Conference on Information and Management Sciences

作者： ~(a,b)Rongxia Zhang ~c Hui Liu ~a Shusheng Zhang a School of Mechatronics,Northwestern Polytechnical University,Xi’an 710072,china b china academy of space technology,beijing 100094,china c Department of Mathematical Sciences,Tsinghua University,beijing 100084,china

A new image coding method based on S-WT and dyadic rectangular tiling is proposed here,where the S-WT is a kind of transforms proposed in[1],and with the only difference with the standard wavelet transform is that the for- mer allows more *** the directional property in a small region is more regular than in a big block gen- erally,in order to sufficient make use of the multidirection- ality and directional vanishing moment(DVM)of S-WT,the input image is divided into many smaller *** of the popular quad-tree segmentation,we utilize dyadic rectan- gular tiling which is like the"dyadic CART"[2] to achieve spatial anisotropic segmentation,and all the tiles taken from the input image,are called dyadic *** splitting cri- terion is on the rate-distortion sense with empirical formula proposed in[3],where the empirical formula is used to de- termine optimal wavelet packet *** the dyadic rectangular tiling is more feasible than quad-tree,it is still constrained,so a neighboring nodes joint-coding strategy is implemented as in[4].After the optimal tiling is obtained,a resource bit allocation algorithm is fast implemented with the model proposed in[5].Because of the overcomplete property of the segmentation dictionary and its tree structure,the algo- rithm is fast and *** results indicate that our algorithms perform better compared to some state-of-the-art image coders.

关键词： Dyadic rectangular tiling Dominant directions S-WT DVM LZC Rate-distortion Joint-coding Deblocking

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Onboard Laser Time Transfer Payload and Its Application for ...