中国科学院机构知识库网格系统: 检索

Development of the advanced high-enthalpy test facility for hypersonic vehicles 会议论文 OAI收割
The 29th International Symposium on Rarefied Gas Dynamics, 中国陕西西安, 2014-07-13
作者:

收藏 | 浏览/下载：16/0 | 提交时间：2015/09/10

enthalpy facility challenging capable aerospace promoting detonation viewing facilities tunnel

A new low-bandwidth and wireless transmission scheme for CCd image (EI CONFERENCE) 会议论文 OAI收割
2012 International Symposium on Photonics and Optoelectronics, SOPO 2012, May 21, 2012 - May 23, 2012, Shanghai, China
作者: Zhang Y.

收藏 | 浏览/下载：34/0 | 提交时间：2013/03/25

The CCD (Charge-coupled Device) image sensor with its high resolution is capable of providing high definition image. However transmission requires high bandwidth which makes it very difficult to process and transmit in a long distance. The purpose of this paper is to propose a new method to process and transmit CCD image which can guarantee a low-bandwidth and long-distance data transmission. The innovation is that the transmission content of CCD image data can be flexibly selected and compressed firstly which will reduce the transmission data. Then it is processed on the base of communication protocol so that it can be fit for wireless transmission. At last it is transformed into wireless signal and transmitted using 3G technology. As a result the paper presents a wireless transmission scheme with the rate of 1.5Mbps for CCD image. 2012 IEEE.

The optical design of cubic phase plate testing system (EI CONFERENCE) 会议论文 OAI收割
2011 Symposium on Photonics and Optoelectronics, SOPO 2011, May 16, 2011 - May 18, 2011, Wuhan, China
作者: Zhang X.; Zhang X.; Zhang X.; Zhang Y.

收藏 | 浏览/下载：19/0 | 提交时间：2013/03/25

Computer-generated holograms (CGH) have been widely used for years in optical testing of aspheric surfaces in combination with Fizeau interferometers. With the development of diffraction optics computer technology and micro-processing technology the accuracy of the CGH testing can achieve a hundredth of a wave and the cost is reduced greatly. CGH is capable of producing an optical wavefront with any desired shape. So it is fascinating and will have good prospects to test free-form surfaces using CGH. As the CGH can create any wavefront shape it can also be used in unsymmetrical aspherical surfaces testing. Taking the cubic surface as an example this paper gives a method to test unsymmetrical surfaces. This paper gives the design to test a cubic surface. And the separation of the diffraction orders and the binary process of the continuous CGH phase function are discussed in detail. The alignment tolerance of the test system and the CGH fabrication tolerance are analyzed. We also present an idea using a CGH and two spherical lenses as null lens to test the cubic surface when the surface deviation is great. 2011 IEEE.

An advanced LEO satellite network model based on MPLS-TP (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on Advanced Intelligence and Awareness Internet, AIAI 2010, October 23, 2010 - October 25, 2010, Beijing, China
作者: Zhang Y.

收藏 | 浏览/下载：18/0 | 提交时间：2013/03/25

LEO (Low Earth Orbit) satellite networks are capable of providing broadband access to end users in any part of the world. With the characteristics of high-speed movement and rapid dynamic topology of LEO satellites networking has always been one of the key issues in LEO satellite network. MPLS-TP (Multi-Protocol Label Switching-Transport Profile) is an excellent packet transport network (PTN) technology in terrestrial networks which can support multi-service and have perfect function of QoS (Quality of Service) OAM (Operation Administration Maintenance) and survivability. In this paper the characteristics of LEO satellite network and functional architecture of MPLS-TP are introduced. Then an advanced LEO satellite network model based on MPLS-TP (ALSN-M) is proposed which can guarantee a connection-oriented seamless data transmission. Furthermore topology and routing algorithms of proposed LEO satellite network model is analyzed. In the end the paper describes how to setup and remove a LSP (Label Switched Path) and how to maintain an exiting LSP when a handover happens.

An intelligent video surveillance system (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on E-Product E-Service and E-Entertainment, ICEEE2010, November 7, 2010 - November 9, 2010, Henan, China
Gao S.

收藏 | 浏览/下载：16/0 | 提交时间：2013/03/25

This paper presents an intelligent video surveillance system. The system is composed of one or more nodes flexibly according to the application scenarios such as private properties banks and museums. Each node is an autonomous vision-based device capable to perform intelligent tasks. It is able to digitize and compress the acquired analog video signals in MPEG-4 standard and then transmit the compressed video stream to the control center. At the same time the node makes use of a statistical approach for real-time detecting moving object and online alarm generation to enable a single human operator to monitor activities over a complex area using a distributed network of active video sensors. The node is implemented on a platform with high performance to ensure that the algorithm is able to run in real-time. Applications demonstrate that the intelligent system has an excellent performance in many scenarios to help people make decisions more accurately and rapidly. 2010 IEEE.

Driving techniques for high frame rate CCD camera (EI CONFERENCE) 会议论文 OAI收割
Electronic Imaging and Multimedia Technology V, November 12, 2007 - November 15, 2007, Beijing, China
Guo W.; Jin L.; Xiong J.

收藏 | 浏览/下载：30/0 | 提交时间：2013/03/25

This paper describes a high-frame rate CCD camera capable of operating at 100 frames/s. This camera utilizes Kodak KAI-0340 an interline transfer CCD with 640(vertical)480(horizontal) pixels. Two output ports are used to read out CCD data and pixel rates approaching 30 MHz. Because of its reduced effective opacity of vertical charge transfer registers interline transfer CCD can cause undesired image artifacts such as random white spots and smear generated in the registers. To increase frame rate a kind of speed-up structure has been incorporated inside KAI-0340 then it is vulnerable to a vertical stripe effect. The phenomena which mentioned above may severely impair the image quality. To solve these problems some electronic methods of eliminating these artifacts are adopted. Special clocking mode can dump the unwanted charge quickly then the fast readout of the images cleared of smear follows immediately. Amplifier is used to sense and correct delay mismatch between the dual phase vertical clock pulses the transition edges become close to coincident so vertical stripes disappear. Results obtained with the CCD camera are shown.

Contour extracting with combination particle filtering and em algorithm (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Related Technologies and Applications, September 9, 2007 - September 12, 2007, Beijing, China
Meng B.; Zhu M.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

The problem of extracting continuous structures from images is a difficult issue in early pattern recognition and image processings[1]. Tracking with contours in a filtering framework requires a dynamical model for prediction. Recently Particle filter is widely used because its multiple hypotheses and versatility within framework. However the good choice of the propagation function is still its main problem. In this paper an improved particle filter EM-PF algorithm is proposed which using the EM (Expectation-Maximization) algorithm to learn the dynamical models. The EM algorithm can explicitly learn the parameters of the dynamical models from training sequences. The advantage of using the EM algorithm in particle filter is that it is capable of improve tracking contour by having accurate model parameters. Though the experiment results we show how our EM-PF can be applied to produces more robust and accurate extracting.

CCD imaging system for the EUV Solar telescope (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
Yan G.; Qian S.; Bing-Xun Y. E.

收藏 | 浏览/下载：17/0 | 提交时间：2013/03/25

In order to develop the detector adapted to the space solar telescope moreover We have employed the mesh experiment to calibrate and test the CCD camera system in 15-24nm we have built a CCD camera system capable of working in the extra ultraviolet (EUV) band the position resolution of about 19 m is obtained at the wavelength of 17.1nm and 19.5nm. which is composed of one phosphor screen one intensified system using a photocathode/micro-channel plate(MCP)/ phosphor one optical taper and one chip of front-illuminated (FI) CCD without screen windows. All of them were stuck one by one with optical glue. The working principle of the camera system is presented

CMOS APS imaging system application in star tracker (EI CONFERENCE) 会议论文 OAI收割
Advanced Materials and Devices for Sensing and Imaging II, November 8, 2004 - November 10, 2004, Beijing, China
作者: Li J.; Liu Y.; Liu Y.

收藏 | 浏览/下载：58/0 | 提交时间：2013/03/25

Small satellites are capable of performing space explore missions that require accurate attitude determination and control. However low weight size power and cost requirements limit the types of attitude sensor of small craft such as CCD are not practical for small satellites. CMOS APS is a good substitute for attitude sensors of small craft. Some of the technical advantages of CMOS APS are no blooming single power low power consumption small size and little support circuitry direct digital output simple to system design in particular radiation-hard characteristic compare with CCD. This paper discusses the application probability of CMOS APS in star tracker for small satellites further more a prototype ground-based star camera based on STAR250 CMOS image sensor has been built. In order to extract stars positions coordinates subpixel accuracy centroiding algorithm has been developed and tested on some ground-based images. Moreover the camera system star sensitivity and noise model are analyzed and the system accuracy is been evaluated. Experimental results indicate that a star camera based on CMOS APS is a viable practical attitude sensor appropriate for space small satellites.

A POSSIBLE NEW PICTURE TO EXPLAIN THE EXPERIMENTS ON THE NEW PARTICLES——TWO NEUTRAL VECTOR GLUON MODEL 期刊论文 OAI收割
Science in China;Ser.A, 1976, 期号: 3, 页码: 347-350
作者:

收藏 | 浏览/下载：8/0 | 提交时间：2015/12/07

picture consistently speaking neutral assumption capable trying explain quark ordinary