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	Lightweight design of large scale theodolite's turntable based on topology optimization of continuum structure (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: Wang Y.; Wang Y.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In order to solve the problem that the weight of large scale theodolite's casting or steel plate welded structure is too heavy lightweight design of large scale turntable based on topology optimization of continuum structure is investigated. Topology optimization could have better optimization efficiency because it can provide the optimized distribution of material and gain optimized structure in conceptual design phase of the structural design. In order to obtain lightweight and high stiffness structure a truss turntable based on topology optimization of continuum structure is presented and the validity of this lightweight structure is examined by finite element analysis. Comparing to the traditional welding steel turntable the lightweight turntable without changing the static displacement can lose 386.48 kg(lightweight ratio is 26.7%) and its first-order natural frequency raises from 167.02Hz to 173.71Hz. Meanwhile in other aspects this turntable also has better performance than traditional structure. 2012 IEEE.
	The aircraft autopilot design of parameters changing in a wide range (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China Zhen D.; Yue Z. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 Autopilot is an important part of aircraft Under the action of the disturbance torque for the flight parameters of aircraft Changing in a wide range the range was about 16km on the basic of analyzing the typical trajectory the max height was about 5100m the trajectory of feature points were selected the deviation of lateral was about 12m taking pitch control loop for example the maximum angle of attack was about 3.6 a sub- PID autopilot was designed using classical control theory the maximum elevator deflection was less than 5 using single-mode Transient suppression method the maximum aileron deflection was less than 2 the overload due to control surface transition deflection was avoided when control parameters changing the maximum roll was less than 5 the verification was done by non-linear simulation. The result showed that: the phase margin of autopilot was greater than 30 the response of overload can accurately track the given overload instruction. An autopilot design method of aircraft of parameter changes in a wide range was provided. 2011 IEEE. the bandwidth was more than 14rad / s the settling time was less than 0.7s the maximum overshoot was 23.3%
	Phase characteristics of laser beam in fibers (EI CONFERENCE) 会议论文 OAI收割 5th International Workshop on Adaptive Optics for Industry and Medicine, August 29, 2005 - September 1, 2005, Beijing, China 作者: Wang L.; Wang L.; Liu J.; Liu J.; Liu J. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 The phase changing rates1 of laser beam in single mode polarization maintaining fiber (PMF) Yb-doped rectangular inner cladding dual-clad fiber (DCF) and Yb-doped large-mode-area dual-clad fiber (LMF) are investigated by means of interference under situations with different exterior disturbance for situations that all the fibers are used as transmission medium only as well as amplifying medium with the last two. In this paper phase fluctuation characteristics of the beam transmitted through the fibers with no amplification are presented. The results show that the phase fluctuation frequencies of the laser beam transmitted through these three kinds of fibers are mainly in the range of 100-200Hz 100-300Hz and 80-400Hz respectively in normal laboratory environment. The phase fluctuation frequencies of the laser beam transmitted through the DCF in cases of when the environment temperature is changing a constant pressure is applied to the fiber and when vibration is applied are mainly in the range of 100-600Hz 100Hz-300Hz and 100-500Hz respectively. In the same cases for the LMF the phase fluctuation frequencies are mainly in the range of 150-600Hz 100-400Hz and 100-1000Hz respectively. It indicates that for realizing phase stabilization the bandwidth of any potential phase control2 system has to be in the range of a few kilohertz.
	Theoretical frame of the saturated freezing soil 期刊论文 iSwitch采集 COLD REGIONS SCIENCE AND TECHNOLOGY, 2002, 卷号: 35, 期号: 2, 页码: 73-80 作者: Li, N; Chen, FX; Su, B; Cheng, GD 收藏 \| 浏览/下载：31/0 \| 提交时间：2019/10/08 multiphase porous medium heat-moisture deformation coupling model phase-changing effective stress principle for freezing soil
	The coupled heat-moisture-mechanic model of the frozen soil 期刊论文 iSwitch采集 COLD REGIONS SCIENCE AND TECHNOLOGY, 2000, 卷号: 31, 期号: 3, 页码: 199-205 作者: Li, N; Chen, B; Chen, FX; Xu, XZ 收藏 \| 浏览/下载：39/0 \| 提交时间：2019/10/08 heat-moisture-deformation coupling model phase-changing frozen soil effective stress principle frozen soil foundation