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Effect of design parameters on the reduction of top piston ring friction (EI CONFERENCE) 会议论文
2nd International Conference on Computer-Aided Design, Manufacturing, Modeling and Simulation, CDMMS 2012, September 21, 2012 - September 23, 2012, Chongqing, China
Wu B.; Zhang Z.; Wang P.
收藏  |  浏览/下载：129/0  |  提交时间：2013/03/25
Image quality assessment based on complex representation of structure information (EI CONFERENCE) 会议论文
2011 International Conference on Electrical, Information Engineering and Mechatronics, EIEM 2011, December 23, 2011 - December 25, 2011, Jiaozuo, Henan, China
Wang Y.; Zhao X.; Mo X.; Wang Y.
收藏  |  浏览/下载：23/0  |  提交时间：2013/03/25
Local variance and single pixel value are combined to describe image structure information using complex method in this paper in order to improve the consistency of objective image assessment result with that of subjective method. The effect of the detail structure information on the image quality was emphasized by this method accordingly. Singular value decomposition was performed on local variance distribution complex matrix. The angle between the singular value vectors of the reference image and the disturbed image was used to measure their structural similarity. Then the quality assessment process was achieved. Results from experiments show that the proposed method is better consistent with human visual system characteristics than MSE  PSNR  and SSIM. 2012 Springer-Verlag London Limited.  
Image mosaic technique based on the information of edge (EI CONFERENCE) 会议论文
2012 3rd International Conference on Digital Manufacturing and Automation, ICDMA 2012, July 31, 2012 - August 2, 2012, Guilin, Guangxi, China
Wu Z.-G.; Wang M.-J.; Wang Y.-Q.
收藏  |  浏览/下载：27/0  |  提交时间：2013/03/25
Image mosaic is an important branch in the field of image processing. This paper designs and realizes an image mosaic technique based on the information of edge. The technology is suitable for engineering application. First of all  two images of the adjoining frames are processed by convolution operation  get the edge images. And then we cut edge image into pieces and compute their spatial frequency. According to the value of the spatial frequency select reasonable registration model group. We compute correlation strength and the value of movement offset which are the model group and the current frame edge image. We can complete image mosaic by them. We use video sequence which of the resolution is 1024 * 768 do the experiment. The results show that the method has good effect and strong adaptability. Algorithm is high efficiency which running time is 24 ms. It is suitable for real-time processing requirements of the application. This method is an effective mosaic technique which is suitable for engineering application. 2012 IEEE.  
Influence of sensitizer concentration on the upconversion luminescence of NaYF4: Yb3+, Er3+ nanoparticles (EI CONFERENCE) 会议论文
2012 2nd International Conference on Machinery, Materials Science and Engineering Applications, MMSE 2012, June 16, 2012 - June 17, 2012, Wuhan, China
Zhao J.; Shi D.; Zhao Y.; Kong X.
收藏  |  浏览/下载：14/0  |  提交时间：2013/03/25
A series of NaYF4: Yb3+  Er3+ nanoparticles with different doping concentration were successfully prepared by the combination of coprecipitation and hydrothermal methods using sodium citrate as chelator. Upconversion luminescence can be observed in all of the samples at room temperature. Fixed the Er3+ concentration with 1 mol% unchanged  the effect of the Yb3+ concentration on the upconversion luminescence of NaYF4: Yb3+  Er3+ samples were studied when the doped Yb3+ concentrations were 0 mol%  1 mol%  2 mol%  5 mol%  10 mol% and 20 mol%  respectively. As increasing the Yb 3+ concentration  the total intensity of the upconversion luminescence of the samples is increasing while the ratio of red to green emission increases firstly and then decreases. The maximum ratio value is 22.1 when the Yb3+ concentration is 10 mol%. It is found that the cross relaxation and cooperative sensitization effect are the reasons for the phenomenon above. (2012) Trans Tech Publications.  
Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Gu S.; Yan Y.; Xu K.; Jin G.
收藏  |  浏览/下载：37/0  |  提交时间：2013/03/25
With the development of aerospace remote sensing technology  the ground resolution of remote sensing camera enhances continuously. Since there is relative motion between camera and ground target when taking pictures  the target image recorded in recording media is moved and blurred. In order to enhance the imaging quality and resolution of the camera  the image motion had to be compensated. In order to abate the effect of image motion to image quality of space camera and improve the resolution of the camera  the compensation method of image motion to space camera is researched. First  the reason of producing drift angle and adjustment principle are analyzed in this paper. This paper introduce the composition and transmission principle of image motion compensation mechanism. Second  the system adopts 80C31 as controller of drift angle  and adopts stepping motor for actuators  and adopts absolute photoelectric encoder as the drift Angle measuring element. Then the control mathematical model of the image motion compensation mechanism are deduced  and it achieve the closed-loop control of the drift angle position. At the last  this paper analyses the transmission precision of the mechanism. Through the experiment  we measured the actual precision of the image motion compensation mechanism  and compared with the theoretical analysis. There are two major contributions in this paper. First  the traditional image motion compensation mechanism is big volume and quality heavy. This has not fit for the development trend of space camera miniaturization and lightweight. But if reduce the volume and quality of mechanism  it will bring adverse effects for the precision and stiffness of mechanism. For this problem  This paper designed a image motion compensation that have some advantages such as small size  light weight at the same time  high precision  stiffness and so on. This image motion compensation can be applicable to the small optics cameras with high resolution. Second  the traditional mechanism control need to corrected  fitting and iterative for the control formula of mechanism. Only in this way  we can get the optimal control mathematical model. This paper has high precision of the control formula derived. It can achieve the high precision control without fitting  It also simplify the difficulty of control mathematical model establishment. This paper designed the range of adjusting of image motion compensation mechanism between -5 +5. Based on choosing-5  -4  -3  -2  -1  0  +1  +2  +3  +4  +4 as the expectation value of the imaginary drift angle  we get ten groups of the fact data in adjusting drift angle measured. The test results show that the precision of the drift angle control system can be achieved in 1. It can meet the system requirements that the precision of the control system is less than 3'  and it can achieve the high-precision image motion compensation. 2011 SPIE.  
Evaluation of the operating range for ground-based infrared imaging tracking system (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
Zhang B.; Zhang Z.-D.; Zhang S.-M.
收藏  |  浏览/下载：33/0  |  提交时间：2013/03/25
Ground-based infrared imaging tracking system (GIITS) is of great importance for aerial target warning and guard. The operating range is one of the key performance specifications  on the other  which should be calculated  calculate the radiation power received on the detector in order to analysis whether the output signal meets the detection requirements or not  analyzed and studied during the whole GIITS design process. The operating range is mostly influenced by a few factors  without considering the effect of the background radiation. By improving of the traditional method  including atmospheric attenuation  a new operating range calculation model of the GIITS was established based on two requirements. One is that the image size of observed target should meet the requirement of the processor signal extraction. The number of the pixel occupied by target image should be more than 9. The other is that the signal noise ratio (SNR) of the GIITS should not be less than 5 to meet the requirements of the target detection probability and spatial frequency. The SNR calculation equation in form of energy is deduced and the radiation characteristic of the observed target and background are analyzed. When evaluate the operating range of the GIITS using the new method  the performance of GIITS and feature of target and background. This paper firstly makes analysis and summarization on the definite localizations of the traditional operating range equation of the GIITS. The localizations are mainly in two aspects. On one hand  we should successively calculate two operating range values according to two requirements mentioned above and choose the minimum value as the analytic result. In the end  the dispersion of the image and the effect of image dispersion are not considered in the traditional method  an evaluation of operating range for fighter aircraft is accomplished as an example. The influence factors in every aspect on operating range were explored by the calculated result. The new operating range calculation model provides the theoretical basis for the design and applications as well as the comprehensive evaluation of a GIITS. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
An adaptive enhancement means adapt to CR medicine image (EI CONFERENCE) 会议论文
International Conference on Image Processing and Pattern Recognition in Industrial Engineering, August 7, 2010 - August 8, 2010, Xi'an, China
Zhang M.-H.; Zhang Y.-Y.
收藏  |  浏览/下载：17/0  |  提交时间：2013/03/25
Influence of spatial temperature distribution on high accuracy interferometric metrology (EI CONFERENCE) 会议论文
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
Gu Y.; Miao E.; Yan F.; Zhang J.; Yang H.
收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25
We calculate the influence of temperature change on the refractive index of air  establish a model of air temperature distribution and analyze the effect of different temperature distribution on the high accuracy interferometric metrology. First  a revised Edlen formula is employed to acquire the relation between temperature and refractive index of air  followed by introducing the fixed temperature gradient distribution among the spatial grid within the optical cavity between the reference flat and the test flat of the Fizeau interferometer  accompanied by a temperature change random function within each grid. Finally  all the rays through the air layer with different incident angles are traced by Matlab program in order to obtain the final output position  angle and OPD for each ray. The influence of different temperature distribution and the length of the optical cavity in on the testing accuracy can be analyzed through the RMS value that results from repeatable rays tracing. As a result  the horizontal distribution (vertical to optical axis) has a large effect on the testing accuracy. Thus  to realize the high accuracy figure metrology  the horizontal distribution of temperature must be rigorously controlled as well as to shorten the length of the optical cavity to a large extent. The results from our simulation are of great significant for the accuracy analysis of interferometric testing and the research of manufacturing a interferometer. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Modulation transfer function in seeker camera limits resulting from missile flutter caused by aerodynamic force (EI CONFERENCE) 会议论文
2010 2nd International Conference on Industrial Mechatronics and Automation, ICIMA 2010, May 30, 2010 - May 31, 2010, Wuhan, China
Ai X.; Zhang X.; Jiang Z.; Wei Q.; Jia H.
收藏  |  浏览/下载：24/0  |  提交时间：2013/03/25
The imaging quality of seeker in flight mode has been evaluated through analyzing the effects of missile flutter on optical modulation transfer function (MTF) of the optical system. Firstly the data of transverse vibration has been processed to eliminate the trend term caused by the trajectory  then obtained the displacement with two times trapezoidal integration. For the side rotation  the high frequency noise interference in the data has been filtered by using five-point moving average method. Took this model as the quivering rule between the object and the image  and then analyzed the effects of the transverse vibration and the side rotation on imaging quality through MTF. By calculation  the r.m.s value of the image motion caused by missile transverse vibration is 0.026mm  and the side rotation angle is 0.0044 . Through the establishment of two modulation transfer functions (MTF) of image random vibration and linear vibration  the results show that the image quality had declined  and the effect of transverse vibration on image quality is obvious. Through improving the rigidity of the missile and selection of small focal length optical system and shorten the time of exposure can improve the imaging quality of the seeker. 2010 IEEE.  
Thermal difference analysis and athermalization design of infrared optical system (EI CONFERENCE) 会议论文
Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China
Ai X.-Q.; Liu B.; Zhang X.; Jia H.
收藏  |  浏览/下载：25/0  |  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.  

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