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	Combining complementary methods for implicitizing rational tensor product surfaces 期刊论文 OAI收割 COMPUTER-AIDED DESIGN, 2018, 卷号: 104, 页码: 100-112 作者: Shen, Li-Yong; Goldman, Ron \| 收藏 \| 浏览/下载：28/0 \| 提交时间：2018/10/07 Base point Implicitization A-resultant Moving plane Resultant Extraneous factor
	窟野河流域河川基流量变化趋势及其驱动因素期刊论文 OAI收割生态学报, 2013, 卷号: 33, 期号: 05, 页码: 1559-1568 雷泳南; 张晓萍; 张建军; 刘二佳收藏 \| 浏览/下载：53/0 \| 提交时间：2014/10/20 窟野河 Kuye River 基流 base flow 趋势 trend 突变 change point 驱动因素 influence factors
	Novel method for optimizing polishing tool-path in CCOS based on weighted-iterative algorithm (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: Zhang X.-J.; Wang X.; Wang X.; Wang X.; Wang X.-K. 收藏 \| 浏览/下载：47/0 \| 提交时间：2013/03/25 In Computer Controlled Optical Surfacing (CCOS) polishing tool-path is the base of solving other control parameters such as dwell time. In order to improve the fabrication results of polishing off-axis aspheric a novel method to optimize the tool-path is discussed in this paper. The optimizing method named weighted-iterative algorithm is according to the balance principle of the particle system. The power factor of each dwell point represents the requirement of dwell density. Considering the factors which influence the polishing result the power factors cosist of three elements include constant error distribution and dwell distance of workpiece edge. The tool-path is solved by numerical iterative method. In the end an error data is simulated with actual parameters using the matrix-based algorithm with two different tool-paths. The one is X-Y uniform spacing model and the other one is to optimize it based on the first. The comparison shows that the results of the optimized one are much better than traditional one especially the rms convergence rate. Theory of the algorithm is simple and exercisable and it satisfies practical requirement as well. 2009 SPIE.
	Design and tolerance analysis of compensator for high order aspheric surface testing (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Optical Instruments and Technology - Optoelectronic Measurement Technology and Systems, October 19, 2009 - October 22, 2009, Shanghai, China 作者: Chen X.; Liu W.; Chen X.; Chen X. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 High accuracy is required in surface testing of 90nm nodal point lithography projecting lens. By comparing various aspheric surface testing methods the structure layout of the compensator is a meniscus positive lens combined with a Plano-convex positive lens. The design results indicate that: primary and high order aberrations are balanced well we adopt Offner null compensator to test the aspheric surface in the point diffraction interferometer at last. In this paper MTF exceeds diffraction limit an Offner compensator is presented on the base of the third order aberration theory to test concave aspheric surface root-mean-square (RMS) of wave front error /167. The F-number of the system can achieve F/1.64. By the analysis of the process of aspheric surface testing with the designed system the optical construction parameters of which is determined by introducing equal-quantities spherical aberration to compensate all orders of aspheric coefficients. The field of view of the system is 0.02 a loosen distribution of the tolerance was presented based on the accuracy of measuring apparatus. 2009 SPIE.
	Measurement of the surface stress state of the Ni base single-crystal superalloy by XRD during loading 期刊论文 OAI收割 ACTA METALLURGICA SINICA, 2007, 卷号: 43, 期号: 11, 页码: 1161-1165 作者: Zhang Jun; Wang Sucheny; Wu Erdong; Zhang Jian; Lou Langhong \| 收藏 \| 浏览/下载：11/0 \| 提交时间：2021/02/02 Ni base single-crystal superalloy X-ray diffraction stress elastic constant four point bending test
	Study on technology of orientation and north-finding based on fiber optic gyroscope (EI CONFERENCE) 会议论文 OAI收割 2007 IEEE International Conference on Mechatronics and Automation, ICMA 2007, August 5, 2007 - August 8, 2007, Harbin, China Zhang Z.; Sun J.; Wu K. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 North-finding system provides true north azimuth information to all kinds of ground-based equipment. A dynamic automatic north-finder based on the modulation output of fiber optic gyroscope (FOG) is presented in this paper. In this scheme the sine output signal of the FOG was sampled and disposed and then the real north of surveyed point on the surface of earth was calculated. The deviation caused by the platform base tilt was compensated by an accelerator Allan standard deviation is used to analyze the random drift of FOG and establish the random error mode of FOG. The FOG north-finding and laser collimation theodolite are assembled to achieve orientation and aiming integral which lays foundation for switching to project application. 2007 IEEE.
	A new algorithm of image segmentation for overlapping grain image (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 Image segmentation is primary issue in image processing at the same time it is principal problem in low level vision in computer vision field. It is the key technology to process image analysis image comprehend and image depict successfully. Aim at measurement of granularity size of nonmetal grain a new algorithm of image segmentation and parameters calculation for overlapping grain image is studied. The hypostasis of this algorithm is present some new attributes of graph sequence from discrete attribute of graph consequently achieve that pick up the geometrical characteristics from input graph and new graph sequence which in favor of image segmentation is recombined. The conception that image edge denoted with "twin-point" is put forward base on geometrical characters of point image edge is transformed into serial edge and on recombined serial image edge based on direction vector definition of line and some additional restricted conditions the segmentation twin-points are searched with thus image segmentation is accomplished. Serial image edge is transformed into twin-point pattern to realize calculation of area and granularity size of nonmetal grain. The inkling and uncertainty on selection of structure element which base on mathematical morphology are avoided in this algorithm and image segmentation and parameters calculation are realized without changing grain's self statistical characters.
	Error analysis and test study of fiber optic gyroscope north-finder (EI CONFERENCE) 会议论文 OAI收割 Advanced Sensor Systems and Applications II, November 8, 2004 - November 12, 2004, Beijing, China Zhang Z.; Sun J.; Wu K. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 North-finder system is an important application of the inertial technology. It provides true north azimuth information to f all kinds of ground-based equipment. This paper designed a dynamic automatic north-finder based on the modulation output of fiber optic gyroscope (FOG). In this scheme the sine output signal of the FOG was sampled and disposed and then the real north of surveyed point on the surface of earth was calculated. The deviation caused by the base tilt was compensated by an accelerator. The output signals of FOG and accelerator were computed combined with the position sampled from increasing encoder by digital signal processor. Successive rotating technique was adopted to modulate the FOG signal periodically. Most of the low frequency part of random gyro drift errors was compensated. The north-finder accuracy was improved compared with the traditional static measuring method. The test result shows the FOG automatic north-finder obtains 2' true north angle accuracies within not more than three minutes can meet the orientation need of artillery terrain measurement vehicle armored car unmanned drive vehicle geodetic survey and tunnel exploration.
	Ground condition sensing of a snake-like robot 会议论文 OAI收割 IEEE International Conference on Robotics, Intelligent Systems and Signal Processing, Changsha, China, October 8-13, 2003 作者: Lv Y(吕洋); Ma SG(马书根); Li B(李斌); Chen L(陈丽) 收藏 \| 浏览/下载：35/0 \| 提交时间：2012/06/06 Snake-like robot has its unique locomotion mode and can change its locomotion form while the ground condition changed to achieve the best velocity and efficiency. We first analyze the snake-like robot locomotion on different terrains simply then point out the significance to sense the ground status that is the base of choosing different locomotion form on different ground. Last we use force sensors to distinguish the different ground status.