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TSP和PM10监测指标对新疆城市空气质量级别的影响/Influence of monitoring index TSP and PM10 on ambient air quality grade at cities of Xinjiang, China[J] 期刊论文  OAI收割
干旱区地理, 2014, 卷号: 37, 期号: 4, 页码: 731-743
作者:  郭宇宏;  王自发;  康宏;  张小啸;  纪元
  |  收藏  |  浏览/下载：20/0  |  提交时间：2017/12/29
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.  
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：29/0  |  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.  
The research of the accurate measure of static transfer function for the TDI CCD camera (EI CONFERENCE) 会议论文  OAI收割
3rd International Photonics and OptoElectronics Meetings, POEM 2010, November 2, 2010 - November 5, 2010, Wuhan, China
Guo-Ning L.; Long-Xu J.; Jian-Yue R.; Wen-Hua W.; Shuang-Li H.
收藏  |  浏览/下载：23/0  |  提交时间：2013/03/25
In the test course of static transfer function of TDI CCD camera  because of the influence that gets environmental and artificial etc. factor  the value of static transfer function measured at any time is between unceasing fluctuation  so  make accuracy reduce. To solve this problem  a kind of accurate measurement technique of static transfer function is put forward. First  before carrying out the measure of static quiet of transfer function  the best test point of transfer function of the TDI CCD camera must be determined  it is parallel to guarantee the rectangle target surface of parallel optical pipe and camera focal plane maintenance parallel  and again guarantee target strip in rectangle target and TDI CCD in camera focal plane maintenance vertical. TDI CCD catches rectangle target image  per 1000 lines of target mark image as a measures sample of static transfer function  exclude because of atmosphere tremble twisted  vague rectangle target mark image  retain 500 distinct and steady target mark image as measure sample set. Then  calculate the static transfer function of each measure sample respectively  take the average of all static quiet transfer function in measure sample set as the static transfer function of camera. Finally  the measure of the static transfer function for TDI CCD camera makes error analysis. Experimental results indicate that the value of the static transfer function of TDI CCD camera measured with this kind of method is 0.2923  with before measurement technique comparison  the value of static transfer function has raised 0.02  makes the accuracy of the measure of static transfer function have gotten raising.  
Analysis of atmospheric pressure and temperature changes on the image quality of aerial camera (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China
Dong B.; Tian H.-Y.
收藏  |  浏览/下载：27/0  |  提交时间：2013/03/25
This paper starts from the study of the aerial camera's work environment  analyzes the temperature and atmosphere pressure changes on aerial camera's imaging quality of influence. Point out that when the altitude of the camera changes  atmospheric pressure and temperature of constant change  so the camera's optical focal surface position changes  thus affecting the image quality of the camera  causing changes in the camera's focal surface optical  and affecting the camera's image quality. Summarize the rules that the temperature and pressure influence the image quality of the camera in aerial environment. Analyze the various environmental conditions on the impact of camera's image quality. For different types of camera  put forward the corresponding convergence compensation method  and provides a reference value to the development of the aerial camera. 2011 IEEE.  
A study on atmospheric turbulence effects in full-optical free-space communication systems (EI CONFERENCE) 会议论文  OAI收割
2010 6th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2010, September 23, 2010 - September 25, 2010, Chengdu, China
作者:  Liu P.
收藏  |  浏览/下载：21/0  |  提交时间：2013/03/25
Next generation free-space optical communication systems have used fiber-optic technology as the seamless connection between free-space and optical fiber. The full-optical free-space optical communication systems use optical fiber as the receiver to get faster communication speed. The atmospheric turbulence deeply influenced on the optical wave propagated in terrestrial application. As the active receiving area of the full-optical free-space optical communication systems is very small  it is important to research on the atmospheric turbulence effects on the full-optical free-space optical communication system. In this paper  we discuss about both the turbulence-induced intensity fluctuations and the angle-of-arrival effects in full-optical free-space optical communication systems which are used in a few kilometers communication. We gave the numerical results of the atmosphere turbulence effects on the free-space optical communication systems. In order to minimize the atmospheric turbulence influence on the full-optical free-space optical communications system  we also investigate the use of fine tracking system in the communication system. We have set up a full-optical free-space communication system in Tokyo and received useful data from the experiment. We compared the receiving power of the experiment  when the fine tracking system is On and Off. From the experiment results  we can see that the fine tracking system effectively mitigates the atmospheric turbulence and increases the receiving power of the communication system. 2010 IEEE.  
Experiments of second harmonic generation output in pulsed TEA CO 2 laser (EI CONFERENCE) 会议论文  OAI收割
High-Power Lasers and Applications V, October 18, 2010 - October 19, 2010, Beijing, China
作者:  Li D.
收藏  |  浏览/下载：52/0  |  提交时间：2013/03/25
It is always the hot subject to realize the output of high-power laser in the range of 3-5m wavelength. This rang of wave band has greatly important applications in military because it located in the atmosphere window. Generally there are two ways to obtain this range of laser wavelength. One way is through optical parameter oscillation (OPO) from shorter laser wavelength and the other is through second harmonic generation (SHG) from longer laser wavelength. Firstly  the comparison between tow nonlinear crystals ZnGeP2 and AgGaSe2 is conducted for their nonlinear coefficient and damaging threshold in theory. The theoretical results show that the crystal AgGaSe 2 is more suitable for the SHG of pulsed TEA CO2 laser. When using pulsed TEA CO2 laser with wavelength of 9.3m to pumping AgGaSe2 SHG crystal  the wavelength of 4.65m is obtained. In the condition of repetition rate 100Hz  the upmost output power of single pulse is up to level of 1W  which corresponding efficiency of SHG is about 6%. The experimental results show that the polarization of laser beam has greatly influence on the SHG output of the crystal. Under the radiation of 3MW/cm 2 from fundamental wave and the right position for maximal SHG output in the crystal  when polarization of laser beam rotates 4.5  the SHG output of energy decrease about 30%. The research of this paper will make a foundation for further development of mid-infrared laser. 2010 Copyright SPIE - The International Society for Optical Engineering.  
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：57/0  |  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.  
THE ATMOSPHERE INFLUENCE TO AMSR-E MEASUREMENTS OVER SNOW-COVERED AREAS: SIMULATION AND EXPERIMENTS 会议论文  OAI收割
2009 Ieee International Geoscience and Remote Sensing Symposium, Vols 1-5, New York
Qiu, Yubao; Shi, Jiancheng; Lemmetyinen, Juha; Kontu, Anna; PuIiainen, Jouni; Guo, Huadong; Jiang, Lingmei; Wang, James R.; Haikainen, Martti; Zhang, Li
收藏  |  浏览/下载：24/0  |  提交时间：2014/12/07
Analysis of the disturbance of remote aerial detector induced by laser (EI CONFERENCE) 会议论文  OAI收割
High-Power Lasers and Applications III, November 8, 2004 - November 11, 2004, Beijing, China
作者:  Zhou J.;  Fu Y.;  Guo J.;  Guo J.
收藏  |  浏览/下载：41/0  |  提交时间：2013/03/25
It is important to study the interaction effect between laser and photoelectric detector. In most of the laser detecting systems  laser must irradiate the photoelectric detector. The detector will be saturated or damaged easily if the fluence of the laser is higher than the saturation threshold of the detector. Now  many photoelectric detectors are used in space. To achieve their interaction  "Cat's eye" effect is applied to find and locate the remote aerial detector by laser. The possibility and mechanism of disturbance to remote aerial detector induced by laser are analyzed  and the factors of influence are also analyzed. The fluence of laser on the photoactive area of remote aerial detector is estimated. With two samples of CCD and TV tracking system  the mechanism of soft damage to CCD and TV tracking system induced by laser are introduced. The saturation of CCD and crosstalk of CCD are the main reasons of disturbance. When the tracking system is used in wave-door tracking mode  it will lose its tracking target if the saturation or crosstalk of CCD can enter into wave-door. At last  the influence to disturbance induced by atmosphere effect is also analyzed.