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Research on nonlinear relationship between rotation speed and material removal in wheel polishing technology 会议论文  OAI收割
Changchun, China, 2022-07-29
作者:  
Yao, Yongsheng;  Li, Qixin;  Jiang, Xiangmin;  Ding, Jiaoteng;  Ma, Zhen
  |  收藏  |  浏览/下载:21/0  |  提交时间:2023/03/02
Nugget Structure Evolution with Rotation Speed for High-Rotation-Speed Friction-Stir-Welded 6061 Aluminum Alloy 期刊论文  OAI收割
Journal of Materials Engineering and Performance, 2018, 卷号: 27, 期号: 3, 页码: 1378-1386
作者:  
Wu ZQ(吴振强);  Yu T(于涛);  Zhang X(张骁);  Zhu Z(朱智);  Wang M(王敏)
  |  收藏  |  浏览/下载:34/0  |  提交时间:2018/03/25
Effect of rotation speed on nugget structure and property of high rotation speed friction stir welded Al-Mn aluminum alloy 期刊论文  OAI收割
International Journal of Advanced Manufacturing Technology, 2017, 页码: 1-10
作者:  
Zhang HJ(张会杰);  Wang M(王敏);  Qi RL(祁若龙);  Zhu Z(朱智)
收藏  |  浏览/下载:68/0  |  提交时间:2017/04/16
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:37/0  |  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 image restoration of Roll-Swing imaging seeker (EI CONFERENCE) 会议论文  OAI收割
3rd IEEE International Conference on Advanced Computer Control, ICACC 2011, January 18, 2011 - January 20, 2011, Harbin, China
作者:  
Zhang H.;  Zhang H.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
To achieve a correct image receiving for Roll-Swing imaging seeker  the mechanism and imaging process is analyzed. The causes of image rotation are discussed. The influence of the frame encoders' precision on imaging de-rotation quality is analyzed. The Roll-Swing imaging seeker is designed for high-speed aerocraft  thus the received images are greatly degraded due to atmospheric turbulence. A new method of image restoration is proposed for turbulence-degraded images in this paper. The method is to get point spread function (PSF) based on the estimation of optical transfer function (OTF) according to the optical system design simulation. Finally  to obtain the restored image  constrained least squares filtering is used with the known PSF. The experiment results indicate that the new restoration method has a favorable effect to satisfy requirement of the automatic target recognition. 2011 IEEE.  
High precision test method for dynamic imaging of space camera (EI CONFERENCE) 会议论文  OAI收割
2010 IEEE International Conference on Advanced Computer Control, ICACC 2010, March 27, 2010 - March 29, 2010, 445 Hoes Lane - P.O.Box 1331, Piscataway, NJ 08855-1331, United States
作者:  
Jin L.-X.;  Zhang K.;  Zhang K.;  Zhang K.;  Zhang K.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
A test method for dynamic imaging of space TDICCD (Time Delay and Integration Charge Coupled Devices) camera was presented in this paper. The test method adopted the PLL (Phase Locked Loop) technology and CMAC (Cerebella Model Articulation Controller) friction compensation as control strategy. Furthermore  According to this method  a test system for dynamic imaging of space TDICCD camera was designed and implemented. The system simulated the movement of the ground objects relative to the space aerocraft  to validate the capability of image speed match and the dynamic imaging quality of TDICCD camera. The design adopted a precision turntable and a drift turntable to simulate the movement around the earth and the drift motion in different latitude due to the rotation of earth  of the aerocraft. The turntables were drived by permanent magnet torque motor which was powered by PWM (Pulse Width Modulation). The system adopted DSP (Digital Signal Processor) as the control core and reached a very high performance. The experimental results showed that the steady speed error was better than 0.01 % and the instantaneous speed error reached 0.0267%. The precision of the test system designed met the requirement for dynamic imaging of TDICCD camera. 2010 IEEE.  
An image matching algorithm based on sub-block coding (EI CONFERENCE) 会议论文  OAI收割
2nd International Workshop on Computer Science and Engineering, WCSE 2009, October 28, 2009 - October 30, 2009, Qingdao, China
作者:  
Li S.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
In order to improve the speed of matching algorithm and simplify the processing of existing sub-block coding matching  a new template matching method combined local gray value encoding matching and phase correlation is proposed. Matching process is divided into rough matching and fine matching. Rough matching divides the image into certain size blocks called R-block  sums the gray value of each R-block pixel  encodes the R-block according to the gray value distribution of R-block with the adjacent R-block  and matches by step between the template and each search sub-image. Then  fine matching results are obtained using phase correlation according to initial match parameters. The time complexity of the proposed method is (M2) .The new algorithm is faster than traditional algorithm by two orders of magnitude  and the speed has improved twice compared with existing sub-block coding method. Experiments demonstrate that the new algorithm is robust to the linear transformation of pixel grey value and image noise  and it also has the stability of small-angle rotation. 2009 IEEE.  
Study on experiment of grinding SiC mirror with fixed abrasive (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  
Wang X.;  Zhang X.-J.;  Wang X.;  Wang X.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
A brand-new technology for manufacturing SiC reflecting mirror that is different from the traditional method is adopted  which is called as fixed abrasive surfacing technology. Not only the new method achieves better mirror quality with bigger diamond in diameter quickly  but also because of the fixed motion between the abrasive and workpiece and it will be good for surface finishing. During experiment  material removal characteristic which is on SiC under certain rotation speed and pressure by W7  W5  W3.5  W1.5 pellets has been tested. Through those removal curves  we come to a conclusion that the technology not only has a higher removal rate  but also has much more stability. In addition  the surface roughness experiment is mentioned. In the first stage  we achieved a mirror with surface roughness 42.758nm rms with W7 pellets. The surface roughness is descending as we change pellets with smaller diamond in diameter . At the end of experiment  a smooth surface with roughness 1.591nm rms has been achieved after using W1.5 pellets. Experiment results indicate that the technology which manufactures SiC reflecting mirror with fixed abrasive is able to replace the traditional slurry abrasive completely in certain finishing phase and also has a great foreground in application. 2009 SPIE.  
Modeling of satellite borne TDI CCD pitching imaging image motion velocity vector (EI CONFERENCE) 会议论文  OAI收割
2009 IEEE International Conference on Automation and Logistics, ICAL 2009, August 5, 2009 - August 7, 2009, Shenyang, China
作者:  
Zhang L.;  Li S.;  Zhang L.
收藏  |  浏览/下载:14/0  |  提交时间:2013/03/25
In order to obtain three-dimensional observation effect with single satellite borne time delay and integrate charge coupled device (TDI-CCD)  pitching imaging is required. More accurate real-time image motion velocity vector computational model of space camera is also necessary to make the imaging perfect. Imaging motion velocity vector computation model must be set up on image plane at pitching imaging. According to the geometric relationship between the pitching imaging space camera and the Earth's rotation motion  satellite borne TDI CCD pitching imaging motion velocity vector model is derived by mapping the ground speed to the image plane and using coordinate transformation method. The numerical simulation results show that the image velocity model can reduce deviation angle error about 33' and about 30% image motion speed error compared to traditional ground velocity model. 2009 IEEE.  
Target track system design based on circular projection (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
Song H.-J.; Zhu M.; Hu S.; Shen M.-L.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
Template matching is the process of searching the present and the location of a reference image or an object in a scene image. Template matching is a classical problem in a scene analysis: given a reference image of an object  decide whether that object exists in a scene image under analysis  and find its location if it does. The template matching process involves cross-correlating the template with the scene image and computing a measure of similarity between them to determine the displacement. The conventional matching method used the spatial cross-correlation process which is computationally expensive. Some algorithms are proposed for this speed problem  such as pyramid algorithm  but it still can't reach the real-time for bigger model image. Moreover  the cross-correlation algorithm can't be effective when the object in the image is rotated. Therefore  the conventional algorithms can't be used for practical purpose. In this paper  an algorithm for a rotation invariant template matching method based on different value circular projection target tracking algorithm is proposed. This algorithm projects the model image as circular and gets the radius and the sum of the same radius pixel value. The sum of the same radius pixel value is invariable for the same image and the any rotated angle image. Therefore  this algorithm has the rotation invariant property. In order to improve the matching speed and get the illumination invariance  the different value method is combined with circular projection algorithm. This method computes the different value between model image radius pixel sum and the scene image radius pixel sum so that it gets the matching result. The pyramid algorithm also is been applied in order to improve the matching speed. The high speed hardware system also is been design in order to meet the real time requirement of target tracking system. The results show that this system has the good rotate invariance and real-time property.