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Water exchange frequency affects the fractions of sulfur and heavy metals in mariculture sediments 期刊论文  OAI收割
MARINE ENVIRONMENTAL RESEARCH, 2025, 卷号: 204, 页码: 9
作者:  
Li, Zhaoran;  Sheng, Yanqing
  |  收藏  |  浏览/下载:12/0  |  提交时间:2025/01/10
Synthesis of Reduced Graphene Oxide/Zinc ferrite/Nickel nanohybrids: As a Lightweight and High-performance Microwave Absorber in the low frequency 期刊论文  OAI收割
Journal of Materials Science: Materials in Electronics, 2019, 卷号: 30, 期号: 20, 页码: 18496–18505
作者:  
Yang Zenghui;  Yang Rui;  Ma Wei;  Duan Chunjian;  Wang Tingmei
  |  收藏  |  浏览/下载:119/0  |  提交时间:2019/11/14
Structural design of large aperture rectangular mirror for space telescope (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Civil Engineering and Transportation, ICCET 2012, October 27, 2012 - October 28, 2012, Guilin, China
作者:  
Li Z.;  Li Z.
收藏  |  浏览/下载:43/0  |  提交时间:2013/03/25
Structural design of large aperture mirror is one of the key technologies for space telescope development. To meet the requirements of high stiffness  strength and thermal dimensional stability  some factors such as support scheme  materials selection  lightweight design and flexible support design were taken into account. The three supports location of the mirror was determined according to the modal analytical solution. By adjusting the parameters of flexure hinge  influences of gravity  assembly stress and thermal stress on the mirror were reduced obviously. Finite element analysis (FEA) results indicate that the surface accuracy reach to rms10.2nm and 10.8nm under the gravity along optical axis direction and 5C uniform temperature rise respectively  the fundamental frequency of the mirror component is 268Hz. Dynamics test shows that the first order natural frequency is 256Hz  which shows an error less than 5% compared to FEA results. (2013) Trans Tech Publications  Switzerland.  
Lattice Boltzmann Simulations of a pitch-up and pitch-down maneuver of a span-wise flexible wing in a free stream flow Read More: http://arc.aiaa.org/doi/abs/10.2514/6.2012-300 会议论文  OAI收割
50th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition, Nashville, TN, United states, JAN 09-12, 2012
作者:  
Qi DW;  He GW(何国威);  Liu YM
收藏  |  浏览/下载:60/0  |  提交时间:2013/02/26
Adaptive Wiener filtering with Gaussian fitted point spread function in image restoration (EI CONFERENCE) 会议论文  OAI收割
2011 IEEE 2nd International Conference on Software Engineering and Service Science, ICSESS 2011, July 15, 2011 - July 17, 2011, Beijing, China
作者:  
Yang L.;  Zhang X.;  Zhang X.;  Zhang X.;  Yang L.
收藏  |  浏览/下载:44/0  |  提交时间:2013/03/25
In the imaging process of the space remote sensing camera  there was degradation phenomenon in the acquired images. In order to reduce the image blur caused by the degradation  the remote sensing images were restored to give prominence to the characteristic objects in the images. First  the frequency-domain notch filter was adopted to remove strip noises in the images. Then using the ground characters with the knife-edge shape in the images  the point spread function of the imaging system was estimated. In order to improve the accuracy  the estimated point spread function was corrected with Gaussian fitting method. Finally  the images were restored using the adaptive Wiener filtering with the fitted point spread function. Experimental results of the real remote sensing images showed that almost all strip noises in the images were eliminated. After the denoised images were restored  its variance and its gray mean gradient increased  also its laplacian gradient increased. Restoration with Gaussian fitted point spread function is beneficial to interpreting and analyzing the remote sensing images. After restoration  the blur phenomenon of the images is reduced. The characters are highlighted  and the visual effect of the images is clearer. 2011 IEEE.  
Application of particulate reinforced aluminum matrix composite in airborne photoelectric turret (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China
作者:  
Wang P.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
In order to design and manufacture more excellent airborne photoelectric stable turret  modulus of elasticity of 213 GPa and thermal expansion coefficient of 7.9106/K. The frame has decreased the maximum deformation by by 60% and increased the fundamental frequency by 65% as compared with those of aluminum alloy materials  a new type of aeronautical material-particulate reinforced aluminum matrix composite (SiC/Al composite) is investigated. Several crucial technologies  respectively as shown by finite element analysis results. Those are confirmed by vibration test furthermore. Therefore  such as pressureless infiltration technology  a significant lightening effect is achieved and the thermal control load is also reduced. The test result indicates that the stable accuracy of the system achieves 19.8rad and the optical-axis parallelism of pay load is 0.1mrad. The research applies the SiC/Al composites to airborne photoelectric platforms  interface reaction controls and plate's welding are systematically studied. Then  which makes a effective exploration for the new aeronautical material's application. 2011 IEEE.  using SiC/Al composites  the airborne photoelectric stable turret frame is successfully prepared in density of 2.94 g/ cm3  
Contrast research on interpolation and subpixel imaging in CCD geometric superresolution reconstruction (EI CONFERENCE) 会议论文  OAI收割
1st Asia Pacific Conference on Postgraduate Research in Microelectronics and Electronics, PrimeAsia 2009, November 19, 2009 - November 21, 2009, Shanghai, China
作者:  
Xu Y.-S.;  Yang S.-W.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
In order to enhance the resolution of Charge Coupled Device (CCD) pixel with the pixel dimension and focal length of optical system unchanged  the problem of CCD geometric superresolution is educed. The problem is discussed in terms of software and hardware. In software  the bicubic interpolation is introduced  while in hardware  the subpixel imaging method is utilized. The subpixel imaging method integrates two uniform linear CCDs staggered by half dimension of pixel in one device. In operation  the line frequency is doubled. At last  the collected data is interweaved to synthesize a high resolution image. The two methods  bicubic interpolation and subpixel imaging  are simulated with Matlab7.0.1. The qualitative and quantitative analyses are given. The simulated results of lanczos and cubic spline interpolation methods are given simultaneously to show the performance of interpolation. The simulation result shows that the result images quality becomes better in both methods  but compared with bicubic interpolation method  the synthesized image PSNR gained from sub-pixel imaging is averagely enhanced by 2.1682dB  while the elapsed time is reduced to be about one forth. The subpixel imaging method could significantly mitigate the image blur introduced by undersample. 2009 IEEE.