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Chinese Academy of Sciences Institutional Repositories Grid
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Improvement in thermal conductivity of through-plane aligned boron nitride/silicone rubber composites 期刊论文  OAI收割
MATERIALS & DESIGN, 2019, 卷号: 165, 页码: 8
作者:  
Xue, Yang;  Li, Xiaofei;  Wang, Haosheng;  Zhao, Feng;  Zhang, Donghai
  |  收藏  |  浏览/下载:70/0  |  提交时间:2019/04/03
Enhanced Thermal Conductivity of Polyimide Composites with Boron Nitride Nanosheets 期刊论文  OAI收割
SCIENTIFIC REPORTS, 2018, 卷号: 8
作者:  
Wang, Mengjie;  Yu, Jinhong;  Jiang, Nan;  Kang, Ruiyang;  Guo, Liangchao
  |  收藏  |  浏览/下载:50/0  |  提交时间:2018/12/04
Research on the torque characteristic of disc micromotor on axial magnetic field (EI CONFERENCE) 会议论文  OAI收割
2012 2nd International Conference on Consumer Electronics, Communications and Networks, CECNet 2012, April 21, 2012 - April 23, 2012, Three Gorges, China
Liu B.
收藏  |  浏览/下载:53/0  |  提交时间:2013/03/25
In order to increase the electromagnetic torque density of micromotor with axial magnetic field  numerical analysis of permanent magnetic field and electromagnetic torque were deduced and the key factors of increasing torque density of micromotor was obtained. The numerical analysis of three-dimensional magnetic field in air gap produced by spliced sector permanent magnetic poles is done  and the way of improving flux density and permanent magnet use efficiency are given through investigating the influence of magnet thickness  height of air gap and pole interval rate and other parameters to air gap flux density and leakage flux. Based on the test of axial magnetic field and torque characteristic of micromotor  the analysis of micromotor magnetic field and calculation of torque are verified  meanwhile using the plane stator with 0.7mm thickness assemble micromotor having minimum air gap height of 1mm and its torque constant up to 3.8mNm/A. 2012 IEEE.  
Simulation test research of using the Ritchey-Common method for the detection of large flat mirror (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Frontiers of Advanced Materials and Engineering Technology, FAMET 2012, January 4, 2012 - January 5, 2012, Xiamen, China
作者:  
Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:17/0  |  提交时间:2013/03/25
Mechanism of STED microscopy and analysis of the factors affecting resolution (EI CONFERENCE) 会议论文  OAI收割
6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China
Yang P.; Ai H.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
Stimulated emission depletion (STED) microscopy exploits nonlinear saturable optical transition of fluorescent molecules  allowed to overcome Abbe's diffraction-limit and provides diffraction-unlimited resolution in far-field optical microscopy. We elaborate the mechanism of STED and the conditions of depletion. The formula of STED microcopy resolution is deduced through effective point spread function (E-PSF). The STED system resolution is mainly dominated by the quality of the fluorescence depletion patterns in the focal plane. The depletion pattern is mainly affected by STED beam intensity  polarization  phase plate  primary aberrations  STED pulse shape  pulse duration and delay time. In this paper  we found related models and simulate the relationship between the depletion patterns and the parameters  and put forward effective approach to enhance the system resolution. 2010 SPIE.  
Station mode for attitude determination of small-multi-target with high speed (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on E-Product E-Service and E-Entertainment, ICEEE2010, November 7, 2010 - November 9, 2010, Henan, China
作者:  
Wang J.;  Zhao L.;  Li M.
收藏  |  浏览/下载:25/0  |  提交时间:2013/03/25
A key problem of attitude measurement of small-multi-target with high speed is how to decide the optimum of the CMOS stations. A multi-CMOS station mode is designed in this paper  multiple CMOS videos were placed on two parallel sides in measurement system  every two CMOS form an intersection viewing field  multiple viewing field join to cover shooting range  which can augment Effective Viewing Field(EVF)  increase capture ratio of objects with high speed and measurement precision of small objects. When an object passes through the joint area  it will be imaged separately on each CMOS focal plane. Multiple CMOS videos were triggered synchronously  a sequence of image information was extracted  the target attitude was confirmed by digital image processing technology. The merit of station mode is low cost  large measurement scope  extending freely and so on. 2010 IEEE.  
Design and image restoration research of a cubic-phase-plate system (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, April 26, 2010 - April 29, 2010, Dalian, China
作者:  
Zhang J.;  Zhang J.;  Zhang J.;  Shi G.;  Zhang X.
收藏  |  浏览/下载:25/0  |  提交时间:2013/03/25
Wave-front coding technology is a novel jointly optical and digital imaging technology which can greatly extend the depth of focus of optical systems. The image restoration process is an important part of wave-front coding technology. Using wave-front coding makes the modulation transfer function(MTF) values of the optical systems change little over a range of several times the depth of focus  which means the system MTF is quite insensitive to defocus  and there is no zero in the passband. So we can design a single filter for the restoration of images in different defocus positions. However  it's hard to avoid noise during image acquisition and transmission processes. These noises will be amplified in the image restoration  especially in the high frequency part when the MTF drop is relatively low. The restoration process significantly reduces the system signal to noise ratio this way. Aimed at the problem of noise amplification  a new algorithm was proposed which incorporated wavelet denoising into the iterative steps of Lucy-Richardson algorithm. Better restoration results were obtained through the new algorithm  effectively solving the noise amplification problem of original LR algorithm. Two sets of identical triplet imaging systems were designed  in one of which the cubic-phase-plate was added. Imaging experiments of the manufactured systems were carried  and the images of a traditional system and a wave-front coded system before and after decoding were compared. The results show that the designed wave-front coded system can extend the depth of focus by 40 times compared with the traditional system while maintaining the light flux and the image plane resolution. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Thermal difference analysis and athermalization design of infrared optical system (EI CONFERENCE) 会议论文  OAI收割
Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China
作者:  
Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
When infrared optical system works in a large temperature range  the thermal effect of optical lens and optical tube will produce image plane shift and lead to imaging quality deterioration. In order to eliminate the thermal aberration  the athermalization design principles of infrared optical system were introduced  and some commonly used methods of thermal difference compensation were described. Proceeding from single lens  the thermal difference caused by temperature changing was analyzed  and the relationship between temperature and focus shift was obtained. Considering optical tube thermal expansion  a set of equations to estimate the thermal difference of lens group was given. Finally  an infrared optical imaging system that can work under the temperature range of -40C to 60C was design according to athermal technique  in which a new mechanical passive temperature compensation was proposed. Through simulation  the athermalization design could make imaging plane shift the smallest. The simulation results coincided with the theoretical formula  and the design had reference value in engineering. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Resolution performance of extreme ultraviolet telescope (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  
Yang L.;  Chen B.;  Chen B.;  Liang J.-Q.;  Ni Q.-L.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
Extreme Ultraviolet Telescope (EUT) will image solar corona in four EUV narrow bandpasses defined by multilayered coatings deposited on normal incidence optics. In order to make sure it will get sub-arcsecond angular resolution in the mission we have to test its resolution performance on ground. The EUT is aligned by Zygo interferometer first and a global wavefront error of 0.152 peak to valley is obtained ( = 632.8nm ). Because of the difficulty of angular resolution test for EUT at its operating wavelengths  we test its optical performance at visible and UV band. The method is to place the resolution test-target on the focal plane of collimator and illuminate the target by visible and UV light espectively  then the collimated light will go through EUT and image at focal plane on CCD. By analysis of the images obtained in experiments we conclude that the angular resolution of EUT is 1.22 at visible light ( = 570nm ) which is very close to diffraction limit (1.20) and according to these results we estimate that the operational wavelength resolution is better than 0.32  meets design requirements. While for UV light  the angular resolution is 1.53 that is different from diffraction limit (0.53)  the error comes mainly from large pixel of EUV camera. 2009 SPIE.  
Data preprocessing of the exterior field of vision assembling photogrammetric camera (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, July 8, 2007 - July 12, 2007, Chengdu, China
作者:  
Li J.;  Li J.;  Li J.;  Liu J.;  Liu J.
收藏  |  浏览/下载:81/0  |  提交时间:2013/03/25
Transmit array photogrammetric camera can obtain image which is high geometric fidelity and high photogrammetric quality. However  the single chip array CCD image sensor camera can't meet the need of measuring precision and photogrammetric covering area. In order to obtain large numbers of information and extensive photogrammetric covering area  we must increase field of vision angle and improve photogrammetric covering area. And all these objects can be realized by exterior field of vision assembling photogrammetric camera. Two side work must be done before images  which obtained by exterior field of vision assembling photogrammetric camera  be used in photogrammetry. First  all assembling camera focal plane need be converted to a benchmark coordinate focal plane to realize camera digital assembling. Second  images must be re-sampled and processing. Because of coordinate conversion  two images from different assembling cameras can be established function relation  which a pixel of image from a camera is corresponding to a pixel of another image from different camera. But through this conversion  some pixels maybe extrusion together and other pixels separate on an image area. So interpolation direction finding(IDF) is used to obtain these pixels and realize image re-sampling. In this paper  the structure of exterior field of vision assembling photogrammetric camera is analyzed  and the coordinate conversion method of exterior field of vision assembling photogrammetric camera and image gray re-sampling method also can be discussed. All the works are based to data pretreatment of exterior vision assembling photogrammetric camera.