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An auto-focus algorithm of fast search based on combining rough and fine adjustment (EI CONFERENCE) 会议论文  OAI收割
3rd international Conference on Manufacturing Science and Engineering, ICMSE 2012, March 27, 2012 - March 29, 2012, Xiamen, China
作者:  
Zhang S.;  Zhang Y.
收藏  |  浏览/下载:25/0  |  提交时间:2013/03/25
A coarse and fine combined fast search and auto-focusing algorithm was suggested in this paper. This method can automatically search and find the focal plane by evaluating the image definition. The Krisch operator based edge energy function was used as the big-step coarse focusing  and then the wavelet transform based image definition evaluation function  which is sensitivity to the variation in image definition  was used to realize the small-step fine focusing in a narrow range. The un-uniform sampling function of the focusing area selection used in this method greatly reduces the workload and the required time for the data processing. The experimental results indicate that this algorithm can satisfy the requirement of the optical measure equipment for the image focusing. (2012) Trans Tech Publications.  
Thermal-structure analysis of supersonic dome based on three materials (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
Jiang Z.; Ai X.; Wei Q.; Liu B.; Jia H.
收藏  |  浏览/下载:25/0  |  提交时间:2013/03/25
To a supersonic missile  a seeker could enhance the aerodynamic ability due to decrease the resistance in flying. At the same time  the primary function of a seeker has been considered as the most important equipment for a missile  due to the importance for cueing of targets and tracking for the final approach. However  the dome of a seeker  which is made up of glass  has poor mechanical performance. Especially  in the higher altitude  for a dome  in which the aerothermal and pressure loads could destroy the structure easily  it is necessary to do the thermal-structure coupled analysis due to varied materials. In the paper  to take the spherical dome of a seeker as a example  the analysis has been completed according to the varied materials consist of MgF2  Al2O3 and ZnS. The temperature loads and the pressure loads derived from the results of fluent analysis has been forced on the surface of dome  which simulates the actual Mach 2.5 in flying. According to the results of coupled analysis  the SEQV stress of the dome radium 80mm based on three materials had reached to 31MPa  which shows that the strength is sufficient for Mach 2.5  and offered the warranty to design the attaching to missile for the dome. At the same time  the results required the flexible mounting for the dome due to the displacements results  which the crystal material couldn't accept. 2011 IEEE.  
Research on the the device of non-angular vibration for opto-electronic platform (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Smart Structures and Materials in Manufacturing and Testing, April 26, 2010 - April 29, 2010, Dalian, China
An Y.; Song C.-P.; Kuang R.-J.; Jin G.
收藏  |  浏览/下载:31/0  |  提交时间:2013/03/25
The opto-electronic platform is the main equipment for aviation reconnaissance. It is a surveillance system with the function of search  recognition orientation and tracking by opto- electronic instruments. It is made up of opto-electronic instruments which are used to get high quality image  and stabilization tracking system to control stabilization and gesture of platform for exact tracking. The opto-electronic platform purpose is to achieve high quality image. Besides the impact of optic system  the image quality of the system is influenced greatly in the vibration environment. The research worked by Zhao peng which demonstrated the affection caused by angular vibration was worse than which caused by line vibration  and what was multiplied direct ratio with plane altitude. So it is necessary to design a new device which could be used widely and has good angular vibration isolation effect. According to the theory of parallelogram  the non-angular vibration device had been designed with spatial links  and the theory of non-angular vibration was analyzed. The three-dimensional model was set with UG  the analysis was done by ADAMS/vibration software. The acceleration and displacement response of the device in each direction was calculated by inspiriting it with sine wave of the acceleration in three directions  and the stiffness and damp were studied. All the work prove the design principle of the device is reasonable  and the device is adopted to keep the platform motion moving horizontally  at the meantime the device is good at isolating vibration in all directions. 2010 SPIE.  
The experiment of broad band I-4C type OBS in the Southwest India ridge 期刊论文  OAI收割
CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION, 2010, 卷号: 53, 期号: 4, 页码: 1015-1018
Ruan, AG; Li, JB; Chen, YS; Qiu, XL; Wu, ZL; Zhao, MH; Niu, XW; Wang, CL; Wang, XG
收藏  |  浏览/下载:33/0  |  提交时间:2011/07/03
Graph fitting test method for the interpolation error of Moire fringe (EI CONFERENCE) 会议论文  OAI收割
9th International Conference on Electronic Measurement and Instruments, ICEMI 2009, August 16, 2009 - August 19, 2009, Beijing, China
作者:  
Sun Y.;  Sun Y.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
In order to realize the fast test for the interpolation error  the graph fitting test method for the interpolation error of Moire fringe is put forward in this paper. Firstly  the triangular wave Moire fringe photoelectric signal of the encoder whose phase difference is 90 are sampled to get the Lissajous graph of the two signals. Secondly  the single wave represented by the founded subsection function is used to fit the practical Moire fringe Lissajous graph. Then  the fitting result is tested to verify whether it satisfies the accuracy requirement. Lastly  the founded subsection function instead of the practical wave function is used to calculate the interpolation error. Using the graph fitting method to sample the Moire fringe single of 15-bits photoelectric encoder to get the interpolation error curve  the tested maximum interpolation error is 70" and the minimum error is - 69". Comparing with the interpolation error which is received from traditional test method  the change trend of the interpolation error curve is similar  and peak-peak value is almost equality. The results of experiment indicate that: the equipment is convenient and the examination method is efficient and feasible. The measure speed is fast and the manifestation result is intuitionistic. The system can be used in the working field. The method can avoid the speed influence and realize the dynamic interpolation error measure  which is significant for the research of encoder's dynamic accuracy characteristics. 2009 IEEE.  
The spectral feature analysis of semiconductor thin disk laser (EI CONFERENCE) 会议论文  OAI收割
Optoelectronic Materials and Devices II, November 2, 2007 - November 5, 2007, Wuhan, China
作者:  
Li J.;  Wang L.-J.;  Wang L.-J.;  Ning Y.-Q.;  Li J.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
The semiconductor thin disk laser is a new type of semiconductor laser. This work gives the basic operation function of semiconductor disk laser  and analyses the heat effect by the experimentally measured photoluminescence spectrum of the laser chip at different pump power and different temperature. We can see that: with increasing pump power  the thermal effects of the gain material becomes seriously and causes the saturation of carrier lifetime  so the electron-hole pair created in the absorbtion layer have no enough time to rate to one of the wells  and the non-radiative recombination happens in the barrier. When the thermal effects becomes stronger  the chip will not lasing. This phenomenon is from the smaller energy offset between barrier and quantum well. We optimize the original structure design and experimental technology. A non-absorbing AlGaAs layer who is transparent to the pumping and laser wavelength is added to confine the carriers in the quantum wells. At the same time a DBR with double reflecting band is induced to improve the absorbing efficiency of the pumping light. The single QW is replaced by the three narrow QWs  This three QWs structure can add the quantum state of QW  increase the recombination probability of carriers in the QWs and reduce the heat effect. The chemical etch equipment is also improved to control the surface unevenness to be within 50 nm.