中国科学院机构知识库网格系统: 检索

Performance of snow density measurement systems in snow stratigraphies 期刊论文 OAI收割
HYDROLOGY RESEARCH, 2021, 页码: 13
作者: Jiansheng, Hao; Mind'je, Richard; Ting, Feng; Lanhai, Li

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收藏 | 浏览/下载：26/0 | 提交时间：2021/08/19

dielectric permittivity measuring systems gravimetric measuring systems precision and accuracy snow density snow stratigraphies

Performance of snow density measurement systems in snow stratigraphies 期刊论文 OAI收割
HYDROLOGY RESEARCH, 2021, 页码: 13
作者: Jiansheng, Hao

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收藏 | 浏览/下载：15/0 | 提交时间：2021/08/19

dielectric permittivity measuring systems gravimetric measuring systems precision and accuracy snow density snow stratigraphies

A line mapping based automatic registration algorithm of infrared and visible images 会议论文 OAI收割
5th International Symposium on Photoelectronic Detection and Imaging (ISPDI) - Infrared Imaging and Applications, Beijing, June 25-27, 2013
作者: Ai R(艾锐); Shi ZL(史泽林)

收藏 | 浏览/下载：36/0 | 提交时间：2013/12/26

There exist complex gray mapping relationships among infrared and visible images because of the different imaging mechanisms. The difficulty of infrared and visible image registration is to find a reasonable similarity definition. In this paper, we develop a novel image similarity called implicit linesegment similarity(ILS) and a registration algorithm of infrared and visible images based on ILS. Essentially, the algorithm achieves image registration by aligning the corresponding line segment features in two images. First, we extract line segment features and record their coordinate positions in one of the images, and map these line segments into the second image based on the geometric transformation model. Then we iteratively maximize the degree of similarity between the line segment features and correspondence regions in the second image to obtain the model parameters. The advantage of doing this is no need directly measuring the gray similarity between the two images. We adopt a multi-resolution analysis method to calculate the model parameters from coarse to fine on Gaussian scale space. The geometric transformation parameters are finally obtained by the improved Powell algorithm. Comparative experiments demonstrate that the proposed algorithm can effectively achieve the automatic registration for infrared and visible images, and under considerable accuracy it makes a more significant improvement on computational efficiency and anti-noise ability than previously proposed algorithms.

AUV buoyancy regulating device design and simulation analysis 会议论文 OAI收割
2013 International Conference on Material Engineering and Manufacturing Engineering (ICMEME 2013), Hunan, China, November 24-25, 2013
作者: Zheng R(郑荣); Wang Y(王雨); Wu JG(武建国)

收藏 | 浏览/下载：28/0 | 提交时间：2013/12/26

AUV buoyancy regulating device measuring accuracy sensitivity analysis AMESim simulation

The research of round raster readheads scheme (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
Cong J.-F.

收藏 | 浏览/下载：29/0 | 提交时间：2013/03/25

The round raster is extensively applied in all kinds of high accuracy angular displacement measurement and control system. With the development of precise mechanotronics measuring instrument machining center CNC machine and various precise location testing technology a higher request is put forward to the accuracy and the function of raster measurement system. In this article it is concluded that double readheads is the most reasonable configuration scheme through tests of single readhead scheme two readheads and four readheads. (2012) Trans Tech Publications.

Comparison of radiation temperature measurement precision between middlewave and longwave thermal-imaging systems (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
作者: Sun Z.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

A comparison study on temperature measurement precision between middlewave 3-5m and longwave 8-12m measuring thermal imaging systems has been conducted. The study was limited to systems working in indoor conditions and the target's temperature is in the range of 270K900K. First the Disturb Resisting Function (DRF) of infrared systems is deduced. On the base of DRF curve we find that the middlewave infrared system get the smaller influences under the same size disturb compared with the longwave system. A theory of the influence of target's physical characteristic and measurement conditions on the accuracy of temperature measurements has been developed. On the basis of the developed formulas an analysis of the influence of signal disturbances (because of incorrectly assumed emissivity limited transmittance of the atmosphere radiation reflected by the object and shift of optics radiation) on the accuracy of temperature measurement has been made. It has been found that the middlewave systems in typical temperature range offer generally better accuracy in temperature measurement than the longwave ones do. 2012 IEEE.

An accuracy requirement analysis for LED brightness and color correction system (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Transportation, Mechanical, and Electrical Engineering, TMEE 2011, December 16, 2011 - December 18, 2011, Changchun, China
作者: Wang R.

收藏 | 浏览/下载：62/0 | 提交时间：2013/03/25

Brightness and color correction system is working for the color uniform problem of LED display. The correction system can improve LED display's quality greatly. The accuracy of the LED system must consider the accuracy requirements of the color correction system. This paper analyze the accuracy requirements from two aspects. One is that the accuracy requirements should consider the chromatic tolerance for the human eyes the other one is that the accuracy requirements should be associated with the precision of measuring equipment. This paper discuss the accuracy requirement with the CIE1976LUV as a color space to meet the chromatic tolerance of the human eyes and also give an explanation on how the accuracy of the measuring equipment affect the the correction system. Then this paper give a method to ensure the accuracy requirement for the correction system of a LED display. 2011 IEEE.

Laser pulse coded signal frequency measuring device based on DSP and CPLD (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Laser Sensing and Imaging; and Biological and Medical Applications of Photonics Sensing and Imaging, May 24, 2011 - May 26, 2011, Beijing, China
作者: Zhang H.-B.

收藏 | 浏览/下载：37/0 | 提交时间：2013/03/25

Laser pulse code is an anti-jamming measures used in semi-active laser guided weapons. On account of the laser-guided signals adopting pulse coding mode and the weak signal processing it need complex calculations in the frequency measurement process according to the laser pulse code signal time correlation to meet the request in optoelectronic countermeasures in semi-active laser guided weapons. To ensure accurately completing frequency measurement in a short time it needed to carry out self-related process with the pulse arrival time series composed of pulse arrival time calculate the signal repetition period and then identify the letter type to achieve signal decoding from determining the time value number and rank number in a signal cycle by Using CPLD and DSP for signal processing chip designing a laser-guided signal frequency measurement in the pulse frequency measurement device improving the signal processing capability through the appropriate software algorithms. In this article we introduced the principle of frequency measurement of the device described the hardware components of the device the system works and software analyzed the impact of some system factors on the accuracy of the measurement. The experimental results indicated that this system improve the accuracy of the measurement under the premise of volume real-time anti-interference low power of the laser pulse frequency measuring device. The practicality of the design reliability has been demonstrated from the experimental point of view.

Study on sub-pixel techniques for accurate image measurement of displacement (EI CONFERENCE) 会议论文 OAI收割
2011 2nd International Conference on Advanced Measurement and Test, AMT 2011, June 24, 2011 - June 26, 2011, Nanchang, China
作者: Zhang X.; Zhang X.; Zhang X.

收藏 | 浏览/下载：16/0 | 提交时间：2013/03/25

The high resolving power camera was often used to improve the precision of measuring system although its price is high because the accuracy of image measure was limited by the pixel resolving ability of camera. A method of one dimension gray level quadrature sub-pixel to detect edge was presented. This method was applied to measure the displacement of measuring head on 3-coordinate measuring machine. The data of test was shown that this system can distinguish displacement 0.001mm. it is higher accuracy than pixel level. So this method is convenient and fast fit to track and measure the moving object. It is obvious that this method can save the cost of hardware.

Imaging system effects on the measuring accuracy of the optical surface in interferometer (EI CONFERENCE) 会议论文 OAI收割
3rd International Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2011, January 6, 2011 - January 7, 2011, Shanghai, China
Yang W.; Liu M.; Xu W.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

In order to measure high accuracy or mid spatial frequency optical surfaces this study investigated imaging system in Fizeau interferometer. Interferometer is a transferring phase information system. General transfer function can't evaluate the ability of imaging system in interferometer that transfers the phase information of the optical surface. So this paper deduced instrument transfer function (ITF) and used ITF to evaluate the phase information transfer ability of interferometer. We obtained some results about ITF of imaging system by numerical simulation when there are different aberrations in imaging system or measuring optical surfaces were different. Our results indicate that ITF can evaluate the ability of transferring phase information in interferometer and the distortion of imaging system evidently affects the accuracy of interferometric measurements. 2010 IEEE.