中国科学院机构知识库网格系统: 检索

浏览/检索结果: 共7条，第1-7条

帮助

条数/页：排序方式：
	Evaluating the SEBS-estimated evaporative fraction from MODIS data for a complex underlying surface SCI/SSCI论文 OAI收割 2013 作者: Wu H. 收藏 \| 浏览/下载：30/0 \| 提交时间：2014/12/24 EF SEBS MODIS complex surface large-aperture scintillometer balance system sebs energy-balance diurnal behavior evapotranspiration estimation self-preservation algorithm fluxes heat radiation
	Neural network based online traffic signal controller design with reinforcement training (EI CONFERENCE) 会议论文 OAI收割 14th IEEE International Intelligent Transportation Systems Conference, ITSC 2011, October 5, 2011 - October 7, 2011, Washington, DC, United states Dai Y.; Hu J.; Zhao D.; Zhu F. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 Traffic congestion leads to problems like delays decreasing flow rate and higher fuel consumption. Consequently keeping traffic moving as efficiently as possible is not only important to economy but also important to environment. Traffic system is a large complex nonlinear stochastic system. Traditional mathematical methods have some limitations when they are applied in traffic control. Thus computational intelligence (CI) technologies gain more and more attentions. Neural Networks (NNs) is a well developed CI technology with lots of promising applications in traffic signal control (TSC). In this paper a neural network (NN) based signal controller is designed to control the traffic lights in an urban traffic road network. Scenarios of simulation are conducted under a microscopic traffic simulation software. Several criterions are collected. Results demonstrate that through online reinforcement training the controllers obtain better control effects than the widely used pre-time and actuated methods under various traffic conditions. 2011 IEEE.
	Research on infrared dim-point target detection and tracking under sea-sky-line complex background (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: Dong Y.-X.; Zhang H.-B. 收藏 \| 浏览/下载：116/0 \| 提交时间：2013/03/25 Target detection and tracking technology in infrared image is an important part of modern military defense system. Infrared dim-point targets detection and recognition under complex background is a difficulty and important strategic value and challenging research topic. The main objects that carrier-borne infrared vigilance system detected are sea-skimming aircrafts and missiles. Due to the characteristics of wide field of view of vigilance system the target is usually under the sea clutter. Detection and recognition of the target will be taken great difficulties.There are some traditional point target detection algorithms such as adaptive background prediction detecting method. When background has dispersion-decreasing structure the traditional target detection algorithms would be more useful. But when the background has large gray gradient such as sea-sky-line sea waves etc.The bigger false-alarm rate will be taken in these local area.It could not obtain satisfactory results. Because dim-point target itself does not have obvious geometry or texture feature in our opinion from the perspective of mathematics the detection of dim-point targets in image is about singular function analysis.And from the perspective image processing analysis the judgment of isolated singularity in the image is key problem. The foregoing points for dim-point targets detection its essence is a separation of target and background of different singularity characteristics.The image from infrared sensor usually accompanied by different kinds of noise. These external noises could be caused by the complicated background or from the sensor itself. The noise might affect target detection and tracking. Therefore the purpose of the image preprocessing is to reduce the effects from noise also to raise the SNR of image and to increase the contrast of target and background. According to the low sea-skimming infrared flying small target characteristics the median filter is used to eliminate noise improve signal-to-noise ratio then the multi-point multi-storey vertical Sobel algorithm will be used to detect the sea-sky-line so that we can segment sea and sky in the image. Finally using centroid tracking method to capture and trace target. This method has been successfully used to trace target under the sea-sky complex background. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Micro-motion exposure method based on PZT piezoelectric ceramics (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Material and Device Technology for Sensors, June 17, 2009 - June 19, 2009, Beijing, China 作者: Meng Z.; Meng Z. 收藏 \| 浏览/下载：106/0 \| 提交时间：2013/03/25 There mainly is laser digital photofinishing technique and digital photofinishing technique based on LCD consisting of TFT and LCOS in the digital photofinishing field at the present time. The former have a good many merit such as wide color gamut high processing rate large output size and high brightness but his cost is very high his maintain technique being comparatively complex that result in difficult use for people. The utilization ratio of the latter is low because of lower resolution and lower aperture ratio for LCD but the digital photofinishing based on LCD have lower cost and higher utilization ration being suitable for people's current standard of living. Considering above mentioned problem a micro-motion exposure method based on PZT piezoelectric ceramics used in digital image photofinishing is presented. The two-dimension micro-motion exposure system consisting of PZT piezoelectric ceramics LCD panel polarizing film and spring strip is designed. By means of PZT piezoelectric ceramics the LCD panel is removed about the one half of the pixel size of the LCD panel for four times from the original place at the same time imaging system is exposed four times at the printing paper. The software is used to control the time synchronization the exposure time and motion range of the LCD panel. The system has advantages such as shorter response time than 0.1seconds lesser motion error than 0.01 microns high stability and repeatability. Experimental results show that the proposed micro-motion exposure method improve the picture brightness and enlarge output size at the meantime reducing the cost of the system. 2009 SPIE.
	Optical system design with high resolution and large field of view for the remote sensor (EI CONFERENCE) 会议论文 OAI收割 Chang J.; Weng Z.-C.; Wang Y.-T.; Cheng D.-W.; Jiang H.-L. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 In this paper we are presenting a design method and its results for a space optical system with high resolution and wide field of view. This optical system can be used both in infrared and visible configurations. The designing of this system is based on an on-axis three-mirror anastigmatic (TMA) system. Here the on-axis concept allows wide field of view (FOV) enabling a diversity of designs available for the Multi-Object Spectrometer instruments optimized for low scattered and low emissive light. The available FOVs are upto 1 in both spectrum ranges whereas the available aperture range is F/15 - F/10. The final optical system is a three-mirror telescope with two on-axis and one off-axis segment and its resolution is 0.3m or even lower. The distinguished feature of this design is that it maintains diffraction-limited image at wide wavelengths. The technological developments in the field of computer generated shaping of large-sized optical surface details with diffraction-limited imagery have opened new avenues towards the designing techniques. Such techniques permit us to expand these technological opportunities to fabricate the aspherical off-axis mirrors for a complex configuration.
	Method for computer-aided alignment of complex optical system (EI CONFERENCE) 会议论文 OAI收割 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 2, 2005 - November 5, 2005, Zian, China 作者: Yu J. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 For making complex optical system meet the design requirement such as the space camera used in remote sensing and UVX lithophotography especially for off-axis all-reflecting optical system alignment technology is so necessary. In this paper a method is presented. Based on the ideas of linearity instead of non-linearity and difference quotient instead of differential quotient a mathematical model for computer-aided alignment is proposed. This model included the characteristics of the optical system wavefront difference of its exit pupil and its misalignment of the misaligned optical system. Then comparing self-compiled software with alignment package of CODE V as a result this self-compiled software is much more valid than alignment package of CODE V. For a large aperture long focal length and off-axis three-mirror optical system computer-aided alignment is successful. Finally the wavefront error of the middle field is 0.094 waves RMS and the wavefront error of +0.7 field is 0.106 waves RMS and the wavefront error of -0.7 field is 0.125 waves RMS at =632.8nm are obtained.
	Multiple objective-integrated methodology of global optimum decision-making on mineral resources exploitation 期刊论文 OAI收割 COMPUTERS & INDUSTRIAL ENGINEERING, 2004, 卷号: 46, 期号: 2, 页码: 10,363-372 Xu, WX; Wei, YM 收藏 \| 浏览/下载：24/0 \| 提交时间：2012/11/12 complex large system multiple objective decision-making integrated methodology mineral resource exploitation