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	Design of motion adjusting system for space camera based on ultrasonic motor (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China 作者: Sun Z. 收藏 \| 浏览/下载：94/0 \| 提交时间：2013/03/25 Drift angle is a transverse intersection angle of vector of image motion of the space camera. Adjusting the angle could reduce the influence on image quality. Ultrasonic motor (USM) is a new type of actuator using ultrasonic wave stimulated by piezoelectric ceramics. They have many advantages in comparison with conventional electromagnetic motors. In this paper some improvement was designed for control system of drift adjusting mechanism. Based on ultrasonic motor T-60 was designed the drift adjusting system which is composed of the drift adjusting mechanical frame the ultrasonic motor the driver of Ultrasonic Motor the photoelectric encoder and the drift adjusting controller. The TMS320F28335 DSP was adopted as the calculation and control processor photoelectric encoder was used as sensor of position closed loop system and the voltage driving circuit designed as generator of ultrasonic wave. It was built the mathematic model of drive circuit of the ultrasonic motor T-60 using matlab modules. In order to verify the validity of the drift adjusting system was introduced the source of the disturbance and made simulation analysis. It designed the control systems of motor drive for drift adjusting system with the improved PID control. The drift angle adjusting system has such advantages as the small space simple configuration high position control precision fine repeatability self locking property and low powers. It showed that the system could accomplish the mission of drift angle adjusting excellent. 2011 SPIE.
	Displacement estimation by the phase-shiftings of fourier transform in present white noise (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Wu Y.-H. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 Displacement estimation is a fundamental problem in Real-time video image processing. It can be typically approached by theories based on features in spatial domain. This paper presents an algorithm which improves the theory for estimating the moving object's displacement in spatial domain by its Fourier transform frequency spectrum. Because of the characters of Fourier transform the result is based on all the features in the image. Utilizing shift theorem of Fourier transform and auto-registration the algorithm employs the phase spectrum difference in polar coordinate of two frame images sequence with the moving target1 2. The method needn't transform frequency spectrum to spatial domain after calculation comparing with the traditional algorithm which has to search Direc peak and it reduces processing time. Since the technique proposed uses all the image information including all the white noise in the image especially and it's hard to overcome the aliasing from noises but the technique can be an effective way to analyze the result in little white noise by the different characters between high and low frequency bands. It can give the displacement of moving target within 1 pixel of accuracy. Experimental evidence of this performance is presented and the mathematical reasons behind these characteristics are explained in depth. It is proved that the algorithm is fast and simple and can be used in image tracking and video image processing.
	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：44/0 \| 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 Lab*) 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
	Fabrication and electron emission of carbon microtubes (EI CONFERENCE) 会议论文 OAI收割 Technical Digest of the 18th International Vacuum Nanoelectronics Conference, IVNC 2005, July 10, 2005 - July 14, 2005, Oxford, United kingdom 作者: Liu L.; Liu L.; Wang W.; Wang W. 收藏 \| 浏览/下载：46/0 \| 提交时间：2013/03/25 Carbon nanotubes have been attracting attention because of their unique physical properties and their application potential for field emission cathode. Carbon nanotubes possess the following properties favorable for field emission material such as a high aspect ratio and sharp tip high chemical stability high mechanical strength stable at high temperature. Some research works on carbon nanotubes field emitter and field emission display have been reported. Here a kind of carbon microtubes and its field emission properties are introduced. They have some different properties with carbon nanotubes and the density is lower than carbon nanotubes bundles. These carbon microtubes are directly synthesized by liquidoid epitaxy method on silicon substrates at low temperature. The field emission properties of carbon microtubes are reported too. Carbon microtubes film is synthesized in liquid by electrolysis. The graphite plate is as anode and n-silicon substrate with resistivity of 4-8 cm is as cathode. The electrolysis current is about 5-8mA/cm2 and applied voltage is 800-1500V. Temperatures of the methanol base solution is maintained at 60C in process of deposition of carbon microtubes. Carbon microtubes film is observed by scanning electron microscopy(SEM) as shown in fig.1(a b). The wall's thickness of carbon microtube is about 60nm. The diameter of carbon microtube is about 0.8 m. Raman spectrum of carbon microtubes film shows the two peaks at 1342and 1560cm-1. The field emission properties of carbon microtubes are measured in high vacuum chamber(10-5Pa). The emission area of carbon microtubes is 0.5cm 0.5cm. The threshold of field emission of the carbon microtubes film is about 3.6V/ m. Field emission property of carbon microtubes film is shown in fig.2. Another when the electric field between anode and cathode is 10V/ m the electric field distribution on single carbon microtube is also given after calculation according to electric field theory. Fig 3 shows that electric field distribution vertical section on the of single carbon microtube top with 2 m of highness. These results may help us to understand field emission properties of carbon microtubes. According to research results it is found that liquidoid synthesis is simple method to produce carbon microtubes cold cathode material and the carbon microtubes have better field emission properties. 2005 IEEE.
	The three-dimensional focusing behaviors of the compound x-ray lenses (EI CONFERENCE) 会议论文 OAI收割 Optical Design and Testing II, November 8, 2004 - November 11, 2004, Beijing, United states Le Z.; Liu K.; Liang J.; Zhang M.; Quan B. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 A theoretical method for evaluating the three-dimensional focusing performances of the compound x-rays lenses is presented in the present paper. The relationship between the transverse and axial focusing behaviors is considered and a simple calculation that predicts the transverse and axial focusing behaviors of the compound x-ray lenses is also presented. As an example the three-dimensional focusing performance of a compound x-ray lens with Al material is predicted. The dependences of the three-dimensional focusing performances on the compound lenses' structural parameters are observed for the Al compound x-ray lens. Moreover the approximate tolerances in the setting of the receiving planes are also considered for x-rays of 4.95keV 14.99keV and 29.78keV.
	Validation and Analyses of The Simple method For Determining rm of aphids and Mites 期刊论文 OAI收割动物学研究, 1992, 卷号: 13, 期号: 1, 页码: 37-46 作者: Kuang RP; Fleming R \| 收藏 \| 浏览/下载：16/0 \| 提交时间：2010/08/24 Intrinsic Rate Of Increase Aphids Mites Simple Calculation Validation Analyses