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	Analysis of zenith pass problem in a roll-pitch optics seeker (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China 作者: Jiang H. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 There are mainly two kind of structures for a missile two-axes seeker which is always mentioned as elevate-azimuth and roll-pitch. The elevate-azimuth structured seeker has been studied for a long time and it is applied in all sort of missiles. Not only structure design but also control algorithm of the elevate-azimuth seeker are deeply developed. But for elevate-azimuth seeker there are several disadvantages such as big size and large abaxial angle blind. So the elevate-azimuth seeker gimbal angle is designed up to 65 according to relative references. In modern air war it is important for a missile to have the ability of "first recognize" and "first attack". That means the air to air missile seeker is required to be a system with large gimbal angle and large abaxial launch angle. With the mentioned requirement roll-pitch seeker with its advantages smart size and large gimbal angle is studied widely and deeply. The pitch angle of roll-pitch is up to 90 while its roll angle up to n 360. But there are also some disadvantages for the roll-pitch seeker the most troublesome one is the zenith pass problem. The zenith pass problem is brought about from the gimbal kinematics it is said that when target moves in the center of image plane roll servo command gotten from the kinematics algorithm will go to infinite. Math model of zenith pass problem is proposed in this paper and two ways to solve the problem are brought forward. 2011 IEEE.
	Replacement of methane from quartz sand-bearing hydrate with carbon dioxide-in-water emulsion 期刊论文 OAI收割 energy & fuels, 2008, 卷号: 22, 期号: 3, 页码: 1759-1764 作者: Zhou, Xitang; Fan, Shuanshi; Liang, Deqing; Du, Jianwei 收藏 \| 浏览/下载：79/10 \| 提交时间：2010/09/23 The replacement of CH4 from its hydrate in quartz sand with 90:10, 70:30, and 50:50 (W-CO2:W-H2O) carbon dioxide-in-water (C/W) emulsions and liquid CO2 has been performed in a cell with size of empty set 36 x 200 mm. The above emulsions were formed in a new emulsifier, in which the temperature and pressure were 285.2 K and 30 MPa, respectively, and the emulsions were stable for 7-12 h. The results of replacing showed that 13.1-27.1%, 14.1-25.5%, and 14.6-24.3% of CH4 had been displaced from its hydrate with the above emulsions after 24-96 It of replacement, corresponding to about 1.5 times the CH4 replaced with high-pressure liquid CO2. The results also showed that the replacement rate of CH4 with the above emulsions and liquid CO2 decreased from 0.543, 0.587, 0.608, and 0.348 1/h to 0.083, 0.077, 0.069, and 0.063 1/h with the replacement time increased from 24 to 96 h. It has been indicated by this study that the use of CO2 emulsions is advantageous compared to the use of liquid CO2 in replacing CH4 from its hydrate.
	Implementation and stability analysis of the fuzzy controller based on electric-driven simulation turntable (EI CONFERENCE) 会议论文 OAI收割 ISECS International Colloquium on Computing, Communication, Control, and Management, CCCM 2008, August 3, 2008 - August 4, 2008, Guangzhou, China Xie M.-J.; Wang L.-M.; Wang Z.-Q. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 Fuzzy controller was used to resolve the problem of fast tracking and overshoot in electric-driven simulation turntable for its essence belongs to PD control In this system the control rules of fuzzy controller were established according to the step dynamic response process for the speed loop of this system was predigested to be second-orders system. The describing function method was adopted to analyze the stability of the fuzzy control system. It gave the information of stability of system intuitively. The fuzzy controller had been applied in this system successfully. The simulation turntable had no overshooting nearly when its step input signal was close to 90. Experimental results show the implementation method of fuzzy controller is not only simple but also effectual in engineering practice. It also provides an approach of design of fuzzy controller for motion control system. 2008 IEEE.
	Research on the support structure of the primary mirror of large-aperture telescope (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China Yang W.; Jingxu Z. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 Large-aperture telescope can be used in surveying battlefield researching landform searching object real-time monitoring imaging detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important role in military conflicts. The orbit parameter of object quantity geometrical shape parameter and so on can be obtained by detect spatial target. With the development of optical technology people require larger aperture in optics-electronic (OE) system. By increasing optical aperture the ability of collecting light and resolution power in the system can be enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem. With the increase of primary mirror aperture the weight of the primary mirror will become larger than before. The root mean square (rms) of the primary mirror is affected by many factors such as deadweight deformation of heat environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By reducing the weight of primary mirror precision of the system is ensured. During the designing phase one can consider the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of optical system and the effect factors. The final structural design can be reasonable. In an astronomical telescope the surface of reflector is an important part for collecting dark radiation of celestial bodies. Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very high. Optical system of large aperture small wavelength and small focus can receive maximal light intensity. For ground-based optical astronomical telescope the design proposed in the paper can satisfy the requirement of the possible minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the angle diameter range of the minimum atmosphere seeing then 100% of light energy should be focused on the angle diameter range of minimum atmosphere seeing. Because the rms of mirror is very high precise surface machining and accurate the support of mirror are very important tasks during designing and manufacturing the telescope. In the paper various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter telescope system at the Starfire Optical Range (SOR) overviewed simply which was operated by the Directed Energy Directorate of the Air Force Research Laboratory Kirtland AFB NM USA from the ground-based O-E system for the observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter mirror is analyzed.
	Vapor pressures, critical parameters, boiling points, and triple points of ammonia and trideuteroammonia 期刊论文 OAI收割 JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA, 2004, 卷号: 33, 期号: 4, 页码: 1005-1011 作者: Xiang, HW \| 收藏 \| 浏览/下载：26/0 \| 提交时间：2019/04/09 Ammonia Boiling Point Corresponding-states Principle Critical Density Critical Parameters Critical Pressure Critical Temperature Its-90 Thermodynamic Properties Trideuteroammonia Triple Point Vapor Pressure
	Vapor pressure and critical point of tritium oxide 期刊论文 OAI收割 JOURNAL OF PHYSICAL AND CHEMICAL REFERENCE DATA, 2003, 卷号: 32, 期号: 4, 页码: 1707-1711 作者: Xiang, HW \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2019/04/09 Boiling Point Corresponding-states Principle Critical Density Critical Parameters Critical Pressure Critical Temperature Its-90 Triple Point Tritium Oxide Vapor Pressure