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A direct evidence for the energy transfer from phosphorescent molecules to quantum dots in a driving light emitting diode 期刊论文
Organic Electronics, 2019, 卷号: 73, 页码: 337-341
作者:  Z.Zhang;  X.Guan;  Z.H.Kang;  H.Z.Zhang;  Q.H.Zeng
收藏  |  浏览/下载：1/0  |  提交时间：2020/08/24
Design and fabrication of imaging optical systems with freeform surfaces (EI CONFERENCE) 会议论文
Current Developments in Lens Design and Optical Engineering XIII, August 13, 2012 - August 15, 2012, San Diego, CA, United states
Zhang X.; Zheng L.; He X.; Wang L.; Zhang F.; Yu S.; Shi G.; Zhang B.; Liu Q.; Wang T.
收藏  |  浏览/下载：30/0  |  提交时间：2013/03/25
Technology on fabrication of precise SiC aspherical mirror (EI CONFERENCE) 会议论文
2011 International Conference on Materials and Products Manufacturing Technology, ICMPMT 2011, October 28, 2011 - October 30, 2011, Chengdu, China
Zhang Z.
收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25
This paper represents a technique to produce the large size optical aspherical mirror by using reaction-bonded silicon carbide to meet the material requirements of the space used mirrors  based on the characters comparison of all types mirror material. Techniques are described in this paper  including the bonding procedure of silicon carbide to form a mirror shape  the CCOM technology for aspheric grinding  polishing on a home-developed tool -FSGJ-2  and the aspheric profilometry. A specialized Offner Null lens is also developed to measure the aspherical mirror with laser interferometer. With the technology depicted in the paper  a 502mm 298 mm off-axis SiC aspherical mirror is successfully made with a surface accuracy better than 1/50rms  the final result meets the design requirement. (2011) Trans Tech Publications.  
Research on model reference sliding mode control in roll stabilization of aerocraft (EI CONFERENCE) 会议论文
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China
Chu H.-R.
收藏  |  浏览/下载：25/0  |  提交时间：2013/03/25
Aimed at aerospace roll stabilization  control arithmetic based on model reference sliding mode variable structure theory and chattering reduction arithmetic are formulated. Correctness and validity of arithmetic are analyzed. With flight dynamics  the roll-loop mathematic model and reference model are established. Sliding hyperplane is deduced based on model reference sliding mode variable structure theory. Combing with reaching law  control law is derived  and stability of roll-loop is analyzed. Chattering of aileron instructions is alleviate by using boundary layer approach. Digital flying simulation result shows that variable structure control arithmetic realized roll stabilization control  the roll angle is less than 5.3 under powered flight  and that of unpowered flight is less than 0.5  respectively. The command fin angle is less than 1.5. High frequency chattering of fin command nearby the minimum velocity was trailed off by chattering reduction arithmetic. The sliding mode control arithmetic show good performance when aerodynamic coefficients varies 20%. The control arithmetic is easy to be implemented for its simplicity. 2011 IEEE.  
Study on spectrograph for ionosphere: A broadband imaging instrument prototype for far-ultraviolet (EI CONFERENCE) 会议论文
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Yu L.; Wang S.-R.; Lin G.-Y.
收藏  |  浏览/下载：25/0  |  提交时间：2013/03/25
Current research on space-based exploration for the ionosphere needs more advanced technologies. Because the spectral signals in the ionosphere distributing basically in the far-ultraviolet waveband are very weak. Usual spectrometer structures and detectors such as CCD can't receive enough information. Based on this principle of atmospheric sounding  the imaging spectrometer prototype for ionosphere detection application was designed to solve the problem. This prototype consists of the telescope and the imaging spectrometer. The simple structure and small number of mirrors can help higher transmission efficiency be achieved and weak signals detection be implemented. The telescope is an off-axis parabolic mirror and the spectrometer is a modified Czerny-Turner spectral imaging system. Modified Czerny-Turner spectrometer contains a spherical mirror  a fixed plane grating and a toroidal mirror. By adjusting the incident angle to the collimating mirror and using toroidal mirror  coma and astigmatism were corrected well. We also optimize distances between the grating to the focusing mirror and the focusing mirror to the image plane to improve disadvantages of traditional Czerny-Turner structure. Designed results demonstrate that aberrations are substantially corrected  and high image quality can be obtained in broad waveband. The photon counting Wedge-Strip-Anode detector with micro-channel planes as the receiving plane is accepted for the instrument prototype. The other photon counting 2-D detector responding well for weak light such as Cross-Delay line detector and MAMA detector can also be used for detection. The calibration and performances testing system is made of a vacuum system  a deuterium lamp  a monochrometer and the instrument prototype. Results obtained from the experiment show that the spectral resolution is 2.4 nm and the spatial resolution is 80 m. The other calibration experiments are running. The technology of the spectrometer prototype is important for the research and applications of ionosphere remote sensing. 2011 SPIE.  
Establishment of airplane flight model and simulation analysis of landing behavior (EI CONFERENCE) 会议论文
2nd Annual Conference on Electrical and Control Engineering, ICECE 2011, September 16, 2011 - September 18, 2011, Yichang, China
Li M.; Li D.-W.; Jia H.-G.; Li L.
收藏  |  浏览/下载：18/0  |  提交时间：2013/03/25
This paper create a high fidelity plant model of an aircraft landing gear to inclusion into a full aircraft flight simulation for accurately analyzing the performance and influence of landing gear system. The use of domain specific modeling software enables detailed modeling of the physics and facilitates accurate computational simulation of the flight dynamic  aerodynamic  landing gear dynamic and mechanical loads that occur when the landing gear are deployed and retracted during landing and take-off operations. The parameter design space is easily searched by considering a number of different landing scenarios including touching down on one wheel first  to optimize the design. The simulation results show that the aircraft landing gear system mathematical model established appropriately reflects the change of force and moment in the process of taking off and landing  and it is actual in the physical process. 2011 IEEE.  
The angular velocity estimation principal of -- filter based on high sampling rate (EI CONFERENCE) 会议论文
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China
Zhang Y.; Chu H.
收藏  |  浏览/下载：17/0  |  提交时间：2013/03/25
In order to get angular velocity of stabilization servo mechanism from angular position sensors  -- filter and its angular velocity transfer function were predigested. Combing with optimum parameters  -- filter based on high sampling rate was established  the effect of and sample rate on filter nature frequency were evaluated. According to the requirements of stabilization platform  the principle of steady and transient tracking filter differential were proved. With the hypothesis of constant acceleration  the frequency characteristics of angular velocity transfer function were analyzed  three-dimensional Kalman filter was simplified  and the filter parameters were designed. The results show that when the spectrum of input signal was lower than 6rad/s  parameters was 0.02  and sampling period were 0.08ms and 0.1ms respectively  the filter can realize differential exactly  when the spectrum was 9rad/s  the precision was no less than 1.1%  the phase leading of angular position was no less than 70  the natural frequency should be higher than the cut-off frequency of stabilization platform was two or three times. In the engineering of electro-optical stabilization servo mechanism  -- filter has properties of tracking differential  and reached the requirement of platform angular velocity estimation. Also it is one of the effective methods to get angular velocity from angular position sensors. 2011 IEEE.  
Aircraft landing gear simulation using multidomain modeling technology (EI CONFERENCE) 会议论文
2011 International Conference on Information Technology, Computer Engineering and Management Sciences, ICM 2011, September 24, 2011 - September 25, 2011, Nanjing, Jiangsu, China
Li M.; Hao X.-Y.; Han X.-F.; Jia H.-G.
收藏  |  浏览/下载：33/0  |  提交时间：2013/03/25
In order to accurately analyze the performance and influence of landing gear system  this paper presents a high fidelity plant model of an aircraft landing gear to inclusion into a full aircraft flight simulation. The use of domain specific modeling software enables detailed modeling of the physics and facilitates accurate computational simulation of the flight dynamic  aerodynamic  landing gear dynamic and mechanical loads that occur when the landing gear are deployed and retracted during landing and take-off operations. The parameter design space is easily searched by considering a number of different landing scenarios including touching down on one wheel first  to optimize the design. The simulation results show that the aircraft landing gear system mathematical model established appropriately reflects the change of force and moment in the process of taking off and landing  and it is improve the precision of flight simulation. 2011 IEEE.  
A study on atmospheric turbulence effects in full-optical free-space communication systems (EI CONFERENCE) 会议论文
2010 6th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2010, September 23, 2010 - September 25, 2010, Chengdu, China
Wu X.; Liu P.; Matsumoto M.
收藏  |  浏览/下载：15/0  |  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.  
Fabrication of ZnO thin film transistors based on the substrate of glass (EI CONFERENCE) 会议论文
2009 International Symposium on Liquid Crystal Science and Technology, August 2, 2009 - August 5, 2009, Kunming, China
Yang X.; Wang C.; Zhao C.; Tang W.; Gao X.; Yang J.; Liu B.; Qi X.; Du G.; Cao J.
收藏  |  浏览/下载：24/0  |  提交时间：2013/03/25

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