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Approach to the Geopolitical Influences of Great Powers in Southeast Asia: Case Studies of China and the US 期刊论文  OAI收割
CHINESE GEOGRAPHICAL SCIENCE, 2019, 卷号: 29, 期号: 2, 页码: 341-351
作者:  
Qin Qi;  Cheng Shengkui;  Li Fei;  Zhang Shuwen;  Wu Liang
  |  收藏  |  浏览/下载:64/0  |  提交时间:2019/05/22
Approach to the Geopolitical Influences of Great Powers in Southeast Asia: Case Studies of China and the US 期刊论文  OAI收割
CHINESE GEOGRAPHICAL SCIENCE, 2019, 卷号: 29, 期号: 2, 页码: 341-351
作者:  
Qin Qi;  Cheng Shengkui;  Li Fei;  Zhang Shuwen;  Wu Liang
  |  收藏  |  浏览/下载:29/0  |  提交时间:2019/05/22
Approach to the Geopolitical Influences of Great Powers in Southeast Asia: Case Studies of China and the US 期刊论文  OAI收割
CHINESE GEOGRAPHICAL SCIENCE, 2019, 卷号: 29, 期号: 2, 页码: 341-351
作者:  
Qin Qi;  Cheng Shengkui;  Li Fei;  Zhang Shuwen;  Wu Liang
  |  收藏  |  浏览/下载:13/0  |  提交时间:2019/05/22
Physical layer design for free space optical communication (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Control Engineering and Communication Technology, ICCECT 2012, December 7, 2012 - December 9, 2012, Shenyang, Liaoning, China
作者:  
Wang H.;  Zhang Q.;  Guo J.;  Guo J.;  Wang H.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
A small size Free Space Optical Communication System is introduced  including the hardware and the hardware specified physical layer protocol. In detail  the rapid synchronization method to reduce the handshake bandwidth requirement is demonstrated. The hardware of the system includes the laser driver system  the signal amplifying and shaping system  the data interface system. The hardware specified physical layer protocol is used to interface the outer data  serialize and deserialize the data stream  check transmission errors and schedule the data transmission. The overall system is a FIFO-like system and the user can use it as if he's operating a FIFO. The system is designed mainly for terrestrial FSO link whose signal channel is the atmosphere. Due to the complex composition and activity of the atmosphere  this signal channel brings in great influence on the transmitting laser in it  for example  the absorption and scattering of the atmosphere molecules and aerosols  the scintillation of received laser power caused by the turbulence of the atmosphere  all of which results in a much higher Bit Error Rate (BER) of the communication system than wired communication systems leading to frequent resynchronization. In our system  the sampling clock is generated locally using multi-phase sampling technique rather than PLLbased clock recovery  which helps to rapid synchronization. 2012 IEEE.  
Evaluation of the operating range for ground-based infrared imaging tracking system (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:  
Zhang Z.-D.
收藏  |  浏览/下载:48/0  |  提交时间:2013/03/25
Ground-based infrared imaging tracking system (GIITS) is of great importance for aerial target warning and guard. The operating range is one of the key performance specifications  on the other  which should be calculated  calculate the radiation power received on the detector in order to analysis whether the output signal meets the detection requirements or not  analyzed and studied during the whole GIITS design process. The operating range is mostly influenced by a few factors  without considering the effect of the background radiation. By improving of the traditional method  including atmospheric attenuation  a new operating range calculation model of the GIITS was established based on two requirements. One is that the image size of observed target should meet the requirement of the processor signal extraction. The number of the pixel occupied by target image should be more than 9. The other is that the signal noise ratio (SNR) of the GIITS should not be less than 5 to meet the requirements of the target detection probability and spatial frequency. The SNR calculation equation in form of energy is deduced and the radiation characteristic of the observed target and background are analyzed. When evaluate the operating range of the GIITS using the new method  the performance of GIITS and feature of target and background. This paper firstly makes analysis and summarization on the definite localizations of the traditional operating range equation of the GIITS. The localizations are mainly in two aspects. On one hand  we should successively calculate two operating range values according to two requirements mentioned above and choose the minimum value as the analytic result. In the end  the dispersion of the image and the effect of image dispersion are not considered in the traditional method  an evaluation of operating range for fighter aircraft is accomplished as an example. The influence factors in every aspect on operating range were explored by the calculated result. The new operating range calculation model provides the theoretical basis for the design and applications as well as the comprehensive evaluation of a GIITS. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
System design on a field emission with phosphor detection (EI CONFERENCE) 会议论文  OAI收割
2009 International Symposium on Liquid Crystal Science and Technology, August 2, 2009 - August 5, 2009, Kunming, China
作者:  
Li Y.;  Sun T.;  Li Y.;  Li Y.;  Li Y.
收藏  |  浏览/下载:19/0  |  提交时间:2013/03/25
Study of three-mode parametric instability (EI CONFERENCE) 会议论文  OAI收割
8th Edoardo Amaldi Conference on Gravitational Waves, June 21, 2009 - June 26, 2009, New York, NY, United states
Liang F.; Zhao C.; Gras S.; Ju L.; Blair G.
收藏  |  浏览/下载:21/0  |  提交时间:2013/03/25
The effect of parametric instability in advanced interferometric gravitational wave detectors is a potential problem for their proper operation. Great efforts have been made to study the onset of parametric instabilities and to find ways to control them. Here we present an experimental design for studying parametric instability in a 72 m cavity with suspended high quality fused silica mirrors. With 5 W input power and 20 kW circulation power inside the cavity  it is predicted that parametric instability will occur. The resonant condition of parametric instability can be met by thermally tuning the radius of curvature of a test mass. We will present simulation results of parametric gains for different radii of curvature of a test mass. The simulation results will provide the basis for designing the thermal tuning and observation parametric instability experiments. This will provide a test bed for studying parametric instability and its control for next generation detectors. 2010 IOP Publishing Ltd.  
Inhibition of electromagnetic interference in control system based on DSP of high-power TEA CO2 laser (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
作者:  
Meng F.-J.;  Guo L.-H.;  Wang H.-Q.
收藏  |  浏览/下载:40/0  |  提交时间:2013/03/25
The strong electromagnetic interference (EMI) generated in high-power TEA C02 laser system mainly comes from main discharge circuit  pulse spark switch and power supply. Such strong EMI causes great damage and interference to the control system based on DSP. In this paper  we present the interference sources and their distribution and propose the methods of anti-interference. Measures for hardware design include weakening transient ground potential difference by using equipotential lines between devices  using signal isolation interface to inhibit the transient ground potential interference  and rational layout  shielding and filtering to the control system. And methods for software design include range-limited filter  self-diagnosis and self-repair for the critical data and anti-interference during abnormal reset. The EMI has been inhibited effectively by the anti-interference method proposed above. The result shows that: the software anti-interference method is as important as the hardware anti-interference method for the control system in a complex environment of strong EMI. 2010 IEEE.  
Transceiving protocol designc for a free space optical communication system (EI CONFERENCE) 会议论文  OAI收割
2008 International Conference on Optical Instruments and Technology: Optical Systems and Optoelectronic Instruments, November 16, 2008 - November 19, 2008, Beijing, China
Hualong W.; Wanxin S.; Zhongbao X.
收藏  |  浏览/下载:58/0  |  提交时间:2013/03/25
A new transceiving protocol is demonstrated for a Free Space Optical (FSO) communication system  and it's discussed in two parts: the transmitting protocol and the receiving protocol. During the discussion of these two parts  the cooperation of them is also discussed. Different from wired communication  an FSO system modulates the data on a narrow beam of laser transmitting through the free space or the atmosphere  and the protocol presented in this paper is mainly optimized for terrestrial Free Space Optical links  in which the signal channel of the system is mainly the atmosphere. Due to the complex composition and activity of the atmosphere  this signal channel brings in great influence on the transmitting laser in it  for example  the absorption and scattering of the atmosphere molecules and aerosols  the scintillation of received laser power caused by the turbulence of the atmosphere  all of which results in a much higher Bit Error Rate (BER) of the communication system. Thus in designing a protocol for an FSO system  more effort should be taken in the encoding of the data stream  the synchronization of the data stream  error checking and exception handling. The main function of the transmitting protocol includes interfacing the outer input data with a parallel port  buffering the input data  encoding the input data stream  serializing the parallel data and output the serialized data. It also has an output management unit to manage the activity of each part of the transmitting protocol. The main function of the receiving protocol includes filtering and synchronizing the input serial data stream  paralleling the serial data stream  decoding the input data  error checking  exception handling and interfacing the outer receiver with a parallel port. The entire transceiving protocol could be programmed into a single FPGA chip to improve system integrity and reduce the system cost. The presented protocol could be taken as "protocol transparent" for outer interfaces  meaning that when interfacing the presented system to an outer system  you don't have to consider what protocol the outer system transceiving data stream is under  for example  the TCP/IP protocol or anything else  in the case that its I/O interface is a parallel port. Simulation and final experiment prove that the protocol presented is working fine at a certain bit rate scale. 2009 SPIE.  
Research on method of measuring the time of remote explosion point (EI CONFERENCE) 会议论文  OAI收割
27th International Congress on High-Speed Photography and Photonics, September 17, 2006 - September 22, 2006, Xi'an, China
作者:  
Zhou J.;  Fu Y.
收藏  |  浏览/下载:21/0  |  提交时间:2013/03/25