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Improving the ability of the photochemical reflectance index to track canopy light use efficiency through differentiating sunlit and shaded leaves 期刊论文  OAI收割
REMOTE SENSING OF ENVIRONMENT, 2017, 卷号: 194, 页码: 1-15
作者:  
Zhang, Qian;  Chen, Jing M.;  Ju, Weimin;  Wang, Huimin;  Qiu, Feng
  |  收藏  |  浏览/下载:42/0  |  提交时间:2019/09/25
Lagrangian model of zooplankton dispersion:numerical schemes comparisons and parameter sensitivity tests CNKI期刊论文  OAI收割
2011
作者:  
Qiu ZF(丘仲锋);  Andrea M.DOGLIOLI;  He YJ(何宜军);  Francois CARLOTTI
  |  收藏  |  浏览/下载:0/0  |  提交时间:2024/12/18
Lagrangian model of zooplankton dispersion: numerical schemes comparisons and parameter sensitivity tests 期刊论文  OAI收割
CHINESE JOURNAL OF OCEANOLOGY AND LIMNOLOGY, 2011, 卷号: 29, 期号: 2, 页码: 438-445
作者:  
Qiu Zhongfeng;  Doglioli, Andrea M.;  He Yijun;  Carlotti, Francois
  |  收藏  |  浏览/下载:20/0  |  提交时间:2012/07/03
The ship-borne infrared searching and tracking system based on the inertial platform (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者:  
Li Y.;  Zhang H.;  Zhang H.;  Li Y.;  Li Y.
收藏  |  浏览/下载:38/0  |  提交时间:2013/03/25
As a result of the radar system got interferenced or in the state of half silent  it can cause the guided precision drop badly In the modern electronic warfare  therefore it can lead to the equipment depended on electronic guidance cannot strike the incoming goals exactly. It will need to rely on optoelectronic devices to make up for its shortcomings  but when interference is in the process of radar leading  especially the electro-optical equipment is influenced by the roll  pitch and yaw rotation  it can affect the target appear outside of the field of optoelectronic devices for a long time  so the infrared optoelectronic equipment can not exert the superiority  and also it cannot get across weapon-control system "reverse bring" missile against incoming goals. So the conventional ship-borne infrared system unable to track the target of incoming quickly  the ability of optoelectronic rivalry declines heavily.Here we provide a brand new controlling algorithm for the semi-automatic searching and infrared tracking based on inertial navigation platform. Now it is applying well in our XX infrared optoelectronic searching and tracking system. The algorithm is mainly divided into two steps: The artificial mode turns into auto-searching when the deviation of guide exceeds the current scene under the course of leading for radar.When the threshold value of the image picked-up is satisfied by the contrast of the target in the searching scene  the speed computed by using the CA model Least Square Method feeds back to the speed loop. And then combine the infrared information to accomplish the closed-loop control of the infrared optoelectronic system tracking. The algorithm is verified via experiment. Target capturing distance is 22.3 kilometers on the great lead deviation by using the algorithm. But without using the algorithm the capturing distance declines 12 kilometers. The algorithm advances the ability of infrared optoelectronic rivalry and declines the target capturing time by using semi-automatic searching and reliable capturing-tracking  when the lead deviation of the radar is great. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Scene matching based on directional keylines and polar transform (EI CONFERENCE) 会议论文  OAI收割
2010 IEEE 10th International Conference on Signal Processing, ICSP2010, October 24, 2010 - October 28, 2010, Beijing, China
作者:  
Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
Scene matching under complex background is a priority and difficulty in the field of computer vision  it has the characteristics of rotation and scaling invariance  commonly used in matching real-time collected images and photos for navigation. Scene matching techniques are faced with complex natural scenes  anti-light and anti-slight-distortion  the image distortion exist  applicable for complex scene matching. The project has a new idea: combining the keylines with the vectors description based on polar image translation  such as light  and utilize the rotation-scale-invariance vectors to describe the extracted keylines  change of gray levels  this method includes three steps: keylines extraction  perspective  description and matching. Preliminary experiments show that this keylines-based scene matching algorithm is applicable for image matching under complex background. 2010 IEEE.  scaling and other differences  which cause matching difficult. This paper aims to find a scene matching algorithm  
SoC test data compression technique based on RLE-G (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Advanced Measurement and Test, AMT 2010, May 15, 2010 - May 16, 2010, Sanya, China
作者:  
收藏  |  浏览/下载:35/0  |  提交时间:2013/03/25
Test data compression has been an effective way to reduce test data volume and test time  as well as to solve automatic test equipment (ATE) memory and bandwidth limitation. We analyze the limitations of current test data compression algorithm and draw on the previous experience to deduce an optimal compression coding model suitable for SoC test data. In addition  in this paper we make full use of the relevance of the test vectors and the advantages of statistical coding to present an efficient test data compression method RLE-G based on the coding model  and give the RLE-G the optimal compression efficiency of the boundary conditions and realization steps. The experimental results for ISCAS 89 benchmark circuits demonstrate RLE-G have the excellent advantages of high compression ratio. (2010) Trans Tech Publications.  
A new spaceborne compression approach for remote sensing imagery (EI CONFERENCE) 会议论文  OAI收割
ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Xu S.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
After analyzing advantages and disadvantages of these typical encoding methods: SPIHT and VQ  a "DWT+MRLE" approach for spaceborne data compression was proposed in this paper. This approach includes two steps: Discrete Wavelet Transform (DWT) and Modified Run Length Encoding (MRLE). The former used CDF9/7 biorthogonal wavelet filters to powerfully get rid of correlation between pixels in imagery. The later put enlightening information into the lowest bit of some key-position transform coefficients. Consequently  CDF9/7 and MRLE together make hardware platform remain high real-time capability  and help reconstructed images keep good fidelity with PSNR being about 40dB  compared with the original ones. Comparison between experimentations on SPOT4's low-spatial-resolution (10m) imagery and Ikonos2's high-spatial-resolution (1m) imagery  shows this "DWT+MRLE" method having better performance for remote-sensed imagery  especially those of higher resolution. Although inferior to 8:1  Compression Ration (CR) here near 5:1 is greater than France SPOT5's 3:1 and American Ikonos2's 11:2.6 on-board data compression. More important  this method having less computational amount is good for spaceborne capability of real time. The consumed time of different image size is also presented in this paper  based on TI TMSC6416 DSP chip with 600MHz CPU cycle clock.  
High-accuracy real-time automatic thresholding for centroid tracker (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Zhang Y.
收藏  |  浏览/下载:37/0  |  提交时间:2013/03/25
Many of the video image trackers today use the centroid as the tracking point. In engineering  we can get several key pairs of peaks which can include the target and the background around it and use the method of Otsu to get intensity thresholds from them. According to the thresholds  it give a great help for us to get a glancing size  a target's centroid is computed from a binary image to reduce the processing time. Hence thresholding of gray level image to binary image is a decisive step in centroid tracking. How to choose the feat thresholds in clutter is still an intractability problem unsolved today. This paper introduces a high-accuracy real-time automatic thresholding method for centroid tracker. It works well for variety types of target tracking in clutter. The core of this method is to get the entire information contained in the histogram  we can gain the binary image and get the centroid from it. To track the target  so that we can compare the size of the object in the current frame with the former. If the change is little  such as the number of the peaks  the paper also suggests subjoining an eyeshot-window  we consider the object has been tracked well. Otherwise  their height  just like our eyes focus on a target  if the change is bigger than usual  position and other properties in the histogram. Combine with this histogram analysis  we will not miss it unless it is out of our eyeshot  we should analyze the inflection in the histogram to find out what happened to the object. In general  the impression will help us to extract the target in clutter and track it and we will wait its emergence since it has been covered. To obtain the impression  what we have to do is turning the analysis into codes for the tracker to determine a feat threshold. The paper will show the steps in detail. The paper also discusses the hardware architecture which can meet the speed requirement.  the paper offers a idea comes from the method of Snakes