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Accurate calculations of the high-pressure elastic constants based on the first-principles 期刊论文  OAI收割
CHINESE PHYSICS B, 2015, 卷号: 24, 期号: 8, 页码: -
Wang Chen-Ju; Gu Jian-Bing; Kuang Xiao-Yu; Yang Xiang-Dong
收藏  |  浏览/下载:16/0  |  提交时间:2016/04/21
A strong coupled CFD-CSD method on computational aeroelastity (EI CONFERENCE) 会议论文  OAI收割
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China
Xi R.; Jia H.
收藏  |  浏览/下载:67/0  |  提交时间:2013/03/25
In this paper  a strong coupled CFD-CSD method is developed to simulate the aeroelastic phenomena. The CFD solver is based on the finite-volume algorithm for the Navier-Stokes equations on unstructured grid. The CSD solver solves the aeroelastic governing equations in the modal space. Their coupling is realized by a dual-time method. The spring-based smoothing method is adopted to deform and regenerate the aerodynamic grid. Two test cases are selected to validate the authors' method for static and dynamic aeroelastity .The results of the simulation for the static aeroelastic problems of a missile wing show that the Lift Coefficient and Drag Coefficient are severally 7% and 5% lower than those don't consider the elasticity of the wing. The results for the flutter boundary prediction of the AGARD 445.6 wing have been proved much closer to the experiment than using the DLM. This method can describe the effects of fluid viscosity more exactly for highly nonlinear transonic flight conditions. The calculation has proved reliable in the subsonic regime  but not accurate enough in the supersonic regime. 2011 IEEE.  
A new method for comparing Zernike circular polynomials with Zernike annular polynomials in annular pupils (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Jing S.; Dongmei M.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
To compare the difference between Zernike annular polynomial and Zernike circular polynomial  an approximate mathematic relationship between Zernike annular polynomial coefficients and SEIDEL coefficients is proposed. A new method is applied in comparing experiment. For real interferometric data of annular wave front  the SEIDEL aberration calculated in different ways is removed from the original wave front. Residual astigmatism aberration in annular polynomial way is close to zero  but defocus and sphere aberration are 0.002709  -0.00182. The residual SEIDEL using annular polynomial is least. Data used in comparison shows that Zernike annular polynomial is more accurate and meaningful for the decomposition of aberrations and the calculation of Seidel aberrations in annular pupil. The calculation in astigmatism aberration is most accurate and those in defocus and sphere aberration are least accurate  when the first 9 terms are used in approximate solving SEIDEL. More coefficients are needed to obtain the real SEIDEL. 2010 IEEE.  
A new accurate and fast algorithm of sub-pixel image registration (EI CONFERENCE) 会议论文  OAI收割
2010 IEEE 10th International Conference on Signal Processing, ICSP2010, October 24, 2010 - October 28, 2010, Beijing, China
作者:  
He B.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
In terms of large field view and multi-channel TDICCD remote sensing images  previous interpolation methods and curve fitting methods are not able to achieve the high accuracy and fast registration  and their noise immunity and robustness is not high. For that  this paper presents a more accurate and faster method  iterative pixel interpolation and surface fitting method. Firstly  the method uses the some overlapping pixels between multi-channel images. Secondly  the proposed technique  which is based on the maximization of the correlation coefficient function  combines an efficient pixel-moving interpolation scheme with surface fitting  which makes use of accurate interpolation calculation and fast surface fitting in the iterative process. Finally  the accuracy and speed of the algorithm is evaluated by sub-pixel registration of multi-channel images and comparison with other sorts of efficient methods. The experiment results show that the accuracy of the method reaches 0.01 pixels and it is 3 times faster than the interpolation method. In the registration of large field view and multi-channel TDICCD images  the method is accurate and fast  with greatly high stability  noise immunity and robustness. 2010 IEEE.  
Nonlinear analysis method for predicting optical surface deformations resulted from assembly process (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China
Dong W.; Yong Y.; Guang J.
收藏  |  浏览/下载:25/0  |  提交时间:2013/03/25
There are three main nonlinear elements in the large mirror assemblies  which are screw pretension  adhesive stress and state changes in the assembly process. The optical shape will be influenced seriously by these factors. But the impacts will not be shown in linear analysis results  because as the simplification  these factors have been ignored. The nonlinear analysis method for predicting optical surface deformations resulted from assembly process is discussed in detail. Take a typical mirror support structure for example  the nonlinear analysis model was established. Comparing the calculation results with the optical shape test  it is illustrated that nonlinear analysis is more accurate and closer to the test result. And according to the simulation result  the bowl-shaped depression which was discovered in the test can also be explained reasonably. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Dynamic data fixing for IR target radiation characteristics (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Lihua C.; Juan C.
收藏  |  浏览/下载:29/0  |  提交时间:2013/03/25
The main methods to measure the target IR features are the following two ways: test and then measurement  or theoretical and simulation calculation. The former is direct measurement so the results are more accurate but the test is costly and complicated  so that it is limited in the application. Theoretical and simulation calculation are widely used in the target IR radiation calibration. Here we give the basic configuration of the calibration platform for measuring the IR radiation of the large area low temperature blackbody source  and discuss the calibration flowchart and key technologies for atmospheric transmission correction. The dynamic data are analyzed in real time to determine the IR radiation features in the data fusion subsystem  and the experimental results show that the calibration method is feasible and practical. 2010 IEEE.  
System identification of tracking error and evaluation of tracking performance using BP neural network (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Advances in Infrared Imaging and Applications, June 17, 2009 - June 19, 2009, Beijing, China
Zhang N.; Shen X.-H.
收藏  |  浏览/下载:20/0  |  提交时间:2013/03/25
A novel approach for evaluating the tracking performance of optoelectronic theodolite is proposed. First  an equivalent mathematic model of tracking error is established. Then  the equivalent sine signal is inputted to the equivalent model  and the outputs are sampled. The results of evaluating the tracking performance are obtained based on the statistical calculation of output produced by equivalent model. Equivalent model using the BP (Backprogration) neural network structure is identified. The training method of BP neural network adopts the LM (Levenberg-Marquardt) algorithm for the sake of speeding up training process. The BP neural network is trained and tested by using the training and testing samples gotten from the simulation model of optoelectronic theodolite tracking system under MATLAB/SIMULINK. The estimate errors of equivalent model including average error  maximum error and standard error are 2.5872e-0060  2.8 and 1.9. The results show that the equivalent model identified based on BP neural network meets the needs of evaluating the tracking performance of optoelectronic theodolite. The accurate evaluation of tracking performance is achieved. 2009 SPIE.  
Study on color difference estimation method of medicine biochemical analysis (EI CONFERENCE) 会议论文  OAI收割
ICO20: Illumination, Radiation, and Color Technologies, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Zhou Y.;  Zhou F.;  Wang C.
收藏  |  浏览/下载:35/0  |  提交时间:2013/03/25
The biochemical analysis in medicine is an important inspection and diagnosis method in hospital clinic. The biochemical analysis of urine is one important item. The Urine test paper shows corresponding color with different detection project or different illness degree. The color difference between the standard threshold and the test paper color of urine can be used to judge the illness degree  therefore  it can be used in hospital  so that further analysis and diagnosis to urine is gotten. The color is a three-dimensional physical variable concerning psychology  the estimation method of color difference in urine test can have better precision and facility than the conventional test method with one-dimensional reflectance  calibrating organization and family  while reflectance is one-dimensional variable  it can make an accurate diagnose. The digital camera is easy to take an image of urine test paper and is used to carry out the urine biochemical analysis conveniently. On the experiment  so its application prospect is extensive.  the color image of urine test paper is taken by popular color digital camera and saved in the computer which installs a simple color space conversion (RGB &rarr XYZ &rarr L*a*b*) and the calculation software. Test sample is graded according to intelligent detection of quantitative color. The images taken every time were saved in computer  and the whole illness process will be monitored. This method can also use in other medicine biochemical analyses that have relation with color. Experiment result shows that this test method is quick and accurate  
Density-functional theory with optimized effective potential and self-interaction correction for ground states and autoionizing resonances 期刊论文  OAI收割
PHYSICAL REVIEW A, 1997, 卷号: 55, 期号: 5, 页码: 3406
Tong, XM; Chu, SI
收藏  |  浏览/下载:23/0  |  提交时间:2013/09/17