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COMPLEX SURFACE RECONSTRUCTION BASED ON OBJECT-ORIENTED DEVELOPING TOOL VBA

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Chinese Journal of mechanical engineering 2002年第3期15卷 248-251页

作者： Li Yupeng Wang Hong School of mechanical engineering, yanshan university,{3. School of mechanical engineering Yanshan University Qinhuangdao 066004

Taking AutoCAD2000 as platform, an algorithm for the reconstruction ofsurface from scattered data points based on VBA is presented. With this core technology customerscan be free from traditional AutoCAD as an electronic board and begin to create actual presentationof real-world objects. VBA is not only a very powerful tool of development, but with very simplesyntax. Associating with those solids, objects and commands of AutoCAD 2000, VBA notably simplifiesprevious complex algorithms, graphical presentations and processing, etc. Meanwhile, it can avoidappearance of complex data structure and data format in reverse design with other modeling *** VBA to reverse engineering can greatly improve modeling efficiency and facilitate surfacereconstruction.

关键词： Reverse designing Scattered data points Topological mesh VBAenvironment Complex surface reconstruction

A new generation of plastic optical fibers and its functional exploiting

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Science china(Technological Sciences) 2008年第12期51卷 2197-2207页

作者： YU RongJin & ZHANG Bing college of Information Science and engineering,yanshan {3.,qinhuangdao 066004.china college of Information Science and engineering Yanshan University Qinhuangdao China

A major problem of plastic optical fibers(POFs) is large transmission loss in comparison with silica *** adopting a new optical fiber structure,hollow-core Bragg fiber with cobweb-structured cladding,which can suppress the absorption losses of constituent materials by a factor of about 104―106,the problem of POFs with large losses is solved *** the advantage of flexibility and easy bending,the POFs with this structure can guide light with low transmission loss for information and energy in the wavelength range of visible light to terahertz(THz) wave(0.4―1000 μm).This new generation of POFs will find many applications.

关键词： plastic optical fiber hollow-core Bragg fiber cobweb-structured cladding visible light infrared light terahertz wave circular-polarization single-mode

Solution of a hollow thick-wall cylinder subject to quadric function pressures and its limit when l→∞

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Science china(Technological Sciences) 2004年第2期47卷 229-236页

作者： LIU Zhubai1,SHAN Rui2,LIU Wen2 & NI Liyong1 1.college of mechanical engineering,{3. university,qinhuangdao 066004.china 2.college of Science,{3. university,qinhuangdao 066004.china college of mechanical engineering Yanshan University Qinhuangdao China college of Science Yanshan University Qinhuangdao China

The problem of a hollow thick-wall cylinder subject to quadric function pressures is solved with a new stress function, thus laying the basis for solving the spatial symmetric deformation of a hollow cylinder subject ... 详细信息

关键词： quadric function pressure, analytic solution, stress function, hollow cylinder.

Improvement of 3.D FEM Coupled Model on Strip Crown in Hot Rolling

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Journal of Iron and Steel Research International 2012年第3期19卷 14-19页

作者： WANG Tao, XIAO Hong, ZHAO Tie-yong, QI Xiang-dong (college of mechanical and engineering,{3., qinhuangdao 066004. Hebei, china) college of mechanical and engineering Yanshan University Qinhuangdao Hebei China

In order to simulate and analyze hot strip crown and flatness accurately and efficiently, the 3.D （three-di- mensional） coupled model involved in RPFEM （rigid-plastic finite element method） is improved based on the analyti- cal model of forecasting rolling force distribution. In the analytical model, variational method is employed to solve the lateral flow of metal and influential function method is employed to calculate roll deflection, the lateral distribution of rolling force can be obtained rapidly by iterative strategy. Then the 3.D coupled model uses the result as initial distri- bution of rolling force to calculate roll deflection and makes the initial on-load roll gap profile close to the final value, so as to reduce iterations and increase efficiency. Compared with previous algorithms, the improved model can reduce the iterations by about 50% and shorten the computing time by about 60% on the basis of the calculation accuracy.

关键词： rolling force analytical model RPFEM coupled model efficiency

Design of sequence set with group-wise zero correlation window

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The Journal of china Universities of Posts and Telecommunications 2009年第2期16卷 39-41页

作者： WANG Yang-zhi XU Cheng-qian college of Information Science and engineering,yanshan {3.,qinhuangdao 066004.china college of Information Science and engineering Yanshan University Qinhuangdao 066004 China

Zero correlation window （ZCW） or zero correlation zone （ZCZ） sequence can be used in quasi-synchronous code division multiple access （QS-CDMA） system to eliminate multiple access and multipath interferences. However, as the length of ZCW or ZCZ increases, fewer sequences are available. Recently, a new concept, sequence set with group-wise zero correlation window is introduced, which can increase the number of available sequences for a QS-CDMA system. In this article, a new method for generating sequence set with group-wise zero correlation window is presented. This method is based on a Hadamard matrix of size N×N and a pair of Hadamard matrices of size M×M. Compared with previous methods, the proposed sequence set has a group-wise zero correlation window for both periodic and aperiodic cross-correlation functions.

关键词： ZCW group-wise zero correlation window multiuser detection Hadamard matrix

Undercooling and solidification of germanium melts studied by differential scanning calorimeter

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Science china(Physics,Mechanics & Astronomy) 2004年第5期47卷 581-587页

作者： LI Qiang1,2,ZHU Yuying2,HE Yunha3.WANG Xu2,LI Gong1,YU Jinku1 & SU Zhibin1 1.Key Laboratory of Metastable Materials Science &Technology,yanshan university,qinhuangdao {3.china 2.Department of mechanical engineering,yanshan university,qinhuangdao {3.china 3.Department of Environmental & Chemical engineering,yanshan university,qinhuangdao {3. china Key Laboratory of Metastable Materials Science & Technology Yanshan University Qinhuangdao China Department of mechanical engineering Yanshan University Qinhuangdao China Department of Environmental & Chemical engineering Yanshan University Qinhuangdao China

Differential scanning calorimeter combined with flux(dehydrated B2O3. processing was used to realize and precisely measure the undercooling of germanium *** highest undercooling obtained in this way was 190 *** between the undercooling and cooling rate or overheating tem-perature are analyzed *** undercooling obtained is found to be increased with increasing of the cooling rate in the range from 5 to 40 K/*** a given cooling rate,the undercooling reached is increased with the increasing of the overheating temperature of the melt,but tends to be constant at *** of the undercooled germanium melt is investigated at the same *** is clearly shown that,the higher the cooling rate,the shorter time is needed for crystallization.

关键词： germanium, undercooling, solidification, differential scanning calorimeter.

Formation and vanishment of the intragranular microstructure in Si_2N_2O/Si_3._4 nanocomposites

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Science china(Technological Sciences) 2010年第1期53卷 284-286页

作者： LUO JunTing,LIU RiPing & QI Li State Key Laboratory of Metastable Materials Science and Technology,college of mechanical engineering,{3. university,qinhuangdao 066004.china State Key Laboratory of Metastable Materials Science and Technology College of Mechanical Engineering Yanshan University Qinhuangdao China

Si2N2O/Si3.4 nanocomposites were fabricated by liquid phase sintering of amorphous nano-sized silicon nitride *** intragranular microstructure was observed and *** microstructure's β-Si3.4 was formed in Si2N2O matrix at the sintering temperature higher than 1650°*** was discovered that intragranular microstructure could also disappear by transformation during high temperature *** possible mechanisms of the disappearance of intragranular microstructure were *** effect of intragranular microstructure on main mechanical properties was also investigated.

关键词： Si2N2O/Si3.4 nanocomposite intragranular microstructure transformation vanishment

Research on Manufacturing Technology Based on Machine Vision

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武汉理工大学学报 2006年第S2期28卷 402-406页

作者： HU Zhanqi ZHENG Kuijing (mechanical engineering college,{3. university,qinhuangdao 066004.china mechanical engineering college Yanshan UniversityQinhuangdao 066004China

The concept of machine vision based manufacturing technology is proposed first,and the key algorithms used in two-dimensional and three-dimensional machining are discussed in *** information can be derived from the binary images and gray picture after processing and transforming the *** and the parallel cutting method about two-dimen- sional machining are *** approximating algorithm is used to cutting the profile of the *** Scanning al- gorithm used to machining inner part of a *** improved Shape From Shading method with adaptive pre-processing is adopted to reconstruct the three-dimensional *** cutting method is adopted for three-dimensional *** tool path is then gotten from the model,and NC code is formed *** model can be machined conveniently by the lathe, milling machine or *** examples are given to demonstrate the results of lmageCAM system,which is developed by the author to implement the algorithms previously mentioned.

关键词： index terms-machine vision manufacturing technology image processing

NOVEL 6-SPS PARALLEL 3.DIMENSIONAL PLATFORM MANIPULATOR AND ITS FORCE/MOTION TRANSMISSION ANALYSIS

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Chinese Journal of mechanical engineering 2002年第4期15卷 298-302页

作者： Jin Zhenlin School of mechanical engineering, yanshan university,{3.Gao Feng Hebei university of Technology School of mechanical engineering Yanshan University Qinhuangdao 066004 Hebei university of Technology

The unique design for a novel 6-SPS parallel 3.dimensional platformmanipulator with an orthogonal configuration is investigated. The layout feature of the parallelmanipulator is described. Its force/motion transmission capability, evaluation criteria arepresented. At the orthogonal configuration, the criteria and the relationships between the criteriaand the link lengths are analyzed, which is important since it can provide designer a piece ofvaluable information about how to choose the linear actuators. From the analysis of the results itis shown that the force/motion transmission capabilities of the parallel manipulator arecharacterized by isotropy at the orthogonal configuration. The manipulator is particularly suitablefor certain applications in 6-DOF micromanipulators and 6-axis force/moment transducers.

关键词： 6-SPS parallel manipulator 3.dimensional platform manipulator isotropy