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Heat transfer rate characteristics of two-phase closed thermosyphon heat exchanger 期刊论文  OAI收割
RENEWABLE ENERGY, 2021, 卷号: 177, 页码: 397-410
作者:  Song, Wei;  Zheng, Changjin;  Yang, Jiaming
  |  收藏  |  浏览/下载：30/0  |  提交时间：2021/10/21
Numerical simulation of efficient cooling by coupled RR and TCPT on railway embankments in permafrost regions 期刊论文  iSwitch采集
APPLIED THERMAL ENGINEERING, 2018, 卷号: 133, 页码: 351-360
作者:  Hou Yandong;  Wu Qingbai;  Dong Jianhua;  Luo Jing;  Zhang Mingli
收藏  |  浏览/下载：47/0  |  提交时间：2019/10/09
Quantitative reliability analysis of repairable systems with closed-loop feedback based on GO methodology 期刊论文  OAI收割
JOURNAL OF THE BRAZILIAN SOCIETY OF MECHANICAL SCIENCES AND ENGINEERING, 2017, 卷号: 39, 期号: 5, 页码: 1845-1858
作者:  Yi, Xiao-jian;  Dhillon, B. S.;  Dong, Hai-ping;  Shi, Jian;  Jiang, Ji-ping
  |  收藏  |  浏览/下载：32/0  |  提交时间：2018/07/30
Cooling performance of two-phase closed thermosyphons installed at a highway embankment in permafrost regions 期刊论文  iSwitch采集
APPLIED THERMAL ENGINEERING, 2016, 卷号: 98, 页码: 220-227
作者:  Yu, Fan;  Qi, Jilin;  Zhang, Mingyi;  Lai, Yuanming;  Yao, Xiaoliang
收藏  |  浏览/下载：81/0  |  提交时间：2019/10/09
EXPERIMENTAL STUDY OF BUBBLE GROWTH AND FLOW IN SMALL-DIAMETER THERMOSYPHON LOOPS WITH FILLING RATIOS OF 90% AND 95% 期刊论文  OAI收割
JOURNAL OF ENHANCED HEAT TRANSFER, 2014, 卷号: 21, 期号: 1, 页码: 63-73
作者:  Wei, Lingjiao;  Yuan, Dazhong;  Feng, Ya;  Tang, Dawei
收藏  |  浏览/下载：60/0  |  提交时间：2015/10/27
Numerical study on cooling characteristics of two-phase closed thermosyphon embankment in permafrost regions 期刊论文  iSwitch采集
COLD REGIONS SCIENCE AND TECHNOLOGY, 2011, 卷号: 65, 期号: 2, 页码: 203-210
作者:  Zhang, Mingyi;  Lai, Yuanming;  Zhang, Jianming;  Sun, Zhizhong
收藏  |  浏览/下载：35/0  |  提交时间：2019/10/08
Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Gu S.; Yan Y.; Xu K.; Jin G.
收藏  |  浏览/下载：48/0  |  提交时间：2013/03/25
With the development of aerospace remote sensing technology  the ground resolution of remote sensing camera enhances continuously. Since there is relative motion between camera and ground target when taking pictures  the target image recorded in recording media is moved and blurred. In order to enhance the imaging quality and resolution of the camera  the image motion had to be compensated. In order to abate the effect of image motion to image quality of space camera and improve the resolution of the camera  the compensation method of image motion to space camera is researched. First  the reason of producing drift angle and adjustment principle are analyzed in this paper. This paper introduce the composition and transmission principle of image motion compensation mechanism. Second  the system adopts 80C31 as controller of drift angle  and adopts stepping motor for actuators  and adopts absolute photoelectric encoder as the drift Angle measuring element. Then the control mathematical model of the image motion compensation mechanism are deduced  and it achieve the closed-loop control of the drift angle position. At the last  this paper analyses the transmission precision of the mechanism. Through the experiment  we measured the actual precision of the image motion compensation mechanism  and compared with the theoretical analysis. There are two major contributions in this paper. First  the traditional image motion compensation mechanism is big volume and quality heavy. This has not fit for the development trend of space camera miniaturization and lightweight. But if reduce the volume and quality of mechanism  it will bring adverse effects for the precision and stiffness of mechanism. For this problem  This paper designed a image motion compensation that have some advantages such as small size  light weight at the same time  high precision  stiffness and so on. This image motion compensation can be applicable to the small optics cameras with high resolution. Second  the traditional mechanism control need to corrected  fitting and iterative for the control formula of mechanism. Only in this way  we can get the optimal control mathematical model. This paper has high precision of the control formula derived. It can achieve the high precision control without fitting  It also simplify the difficulty of control mathematical model establishment. This paper designed the range of adjusting of image motion compensation mechanism between -5 +5. Based on choosing-5  -4  -3  -2  -1  0  +1  +2  +3  +4  +4 as the expectation value of the imaginary drift angle  we get ten groups of the fact data in adjusting drift angle measured. The test results show that the precision of the drift angle control system can be achieved in 1. It can meet the system requirements that the precision of the control system is less than 3'  and it can achieve the high-precision image motion compensation. 2011 SPIE.  
The ship-borne infrared searching and tracking system based on the inertial platform (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:  Li Y.;  Zhang H.;  Zhang H.;  Li Y.;  Li Y.
收藏  |  浏览/下载：40/0  |  提交时间：2013/03/25
As a result of the radar system got interferenced or in the state of half silent  it can cause the guided precision drop badly In the modern electronic warfare  therefore it can lead to the equipment depended on electronic guidance cannot strike the incoming goals exactly. It will need to rely on optoelectronic devices to make up for its shortcomings  but when interference is in the process of radar leading  especially the electro-optical equipment is influenced by the roll  pitch and yaw rotation  it can affect the target appear outside of the field of optoelectronic devices for a long time  so the infrared optoelectronic equipment can not exert the superiority  and also it cannot get across weapon-control system "reverse bring" missile against incoming goals. So the conventional ship-borne infrared system unable to track the target of incoming quickly  the ability of optoelectronic rivalry declines heavily.Here we provide a brand new controlling algorithm for the semi-automatic searching and infrared tracking based on inertial navigation platform. Now it is applying well in our XX infrared optoelectronic searching and tracking system. The algorithm is mainly divided into two steps: The artificial mode turns into auto-searching when the deviation of guide exceeds the current scene under the course of leading for radar.When the threshold value of the image picked-up is satisfied by the contrast of the target in the searching scene  the speed computed by using the CA model Least Square Method feeds back to the speed loop. And then combine the infrared information to accomplish the closed-loop control of the infrared optoelectronic system tracking. The algorithm is verified via experiment. Target capturing distance is 22.3 kilometers on the great lead deviation by using the algorithm. But without using the algorithm the capturing distance declines 12 kilometers. The algorithm advances the ability of infrared optoelectronic rivalry and declines the target capturing time by using semi-automatic searching and reliable capturing-tracking  when the lead deviation of the radar is great. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
Research on computer control strategy for optical electric tracking system (EI CONFERENCE) 会议论文  OAI收割
2011 IEEE International Conference on Mechatronics and Automation, ICMA 2011, August 7, 2011 - August 10, 2011, Beijing, China
作者:  Li M.
收藏  |  浏览/下载：23/0  |  提交时间：2013/03/25
In this paper  mathematic model and computer control strategy for optical electrical tracking system have been researched and discussed. First  the system's structure and its work process have been analyzed. Second  according to the system's moving law  the system's mathematic model has been built. As to the computer control strategy  trigger guiding  two closed loop PID control method as well as compound control method have been applied to satisfy the tracking accuracy. Third  we apply the bilinear transformation to get the digital system  and the sample time is 800Hz. The simulation results indicate that the maximum tracking error can be limited to less than 0.5 and the regulator time can be 0.04s. Then the control project resonance frequency should be more than 200Hz and the sample frequency should be more than 400Hz to meet the control accuracy requirement. So we can conclude that the system indexes such as swiftness  high accuracy as long as real time have been satisfied. And the requirement of mechanical property has been present which is very useful to mechanical working. 2011 IEEE.  
Research on servo controller for high speed tracking system (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Mechatronic Systems and Automation Systems, MSAS 2011, July 23, 2011 - July 24, 2011, Xi'an, China
作者:  Li M.
收藏  |  浏览/下载：17/0  |  提交时间：2013/03/25
To meet requirement of swiftness and minimization for the tracking system as well as realize horizontal high accuracy tracking measurement  the automatic servo tracking measurement system has been designed. The two closed loop control  bisection method and compound control have been applied into the system. Experimental results show that the maximum tracking error can be limited to less than 0.5and the regulator time can be 0.04s. The control project resonance frequency should be more than 200Hz and the sample frequency should be more than 400Hz to meet the control accuracy requirement. And these specific mechanical properties indexes are useful to mechanical working to make sure the design can be realization. So the research in this paper has important value to the engineering practice. (2011) Trans Tech Publications.