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Influence of the Hole chamfer on the Characteristics of a Multi-hole Orifice Flowmeter

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Fluid Dynamics & Materials Processing 2019年第4期15卷 391-401页

作者： Caizhe Hao Xiaoming Song Zhining Jia Chengde Petroleum College Hebei Instrument&Meter Engineering Technology Research CenterHebei Instrument&Meter Industry Technology Research InstituteChengde067000China

In order to analyze the influence of the hole chamfer on the metering performances of a Multi-hole Orifice Flowmeter and optimize the related orifice structure,a multi-hole orifice flowmeter with DN80 and throttle ratio of 0.45 was considered in the present *** flow field characteristics were determined in the framework of a CFD *** results show that the multi-hole orifice flowmeter with filleting transition around the throttle orifice has higher accuracy in a wide range of the space of parameters,and is more suitable for accurate measurement of fluid in process control.

关键词： Multi-hole orifice differential pressure chamfer CFD simulation

Visual detection method of chamfer Ron the root bottom of textile workpiece roller

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Journal of Measurement Science and Instrumentation 2018年第3期9卷 205-213页

作者： HU Ling-hao LIU Chang jie SHI Chun rain FU Lu hua LU Gang State Key Laboratory of Precision Measuring TechnoZogy and Instruntents Tianjin UniversityTianjin 300072 China Rail-way Test ＆ Certification Center Locomotive ＆ Car Inspection Lab China Acaderrzy of Rail-way SciencesBeijing 100015China

Roller is an important workpiece of automatic spinning machine. Only if the chamferR on the root bottom of roller＇s guide pillar meets processing accuracy requirement can the end face of one roller＇s guide pillar match the correct position of another roller＇s end face on the guide hole. Therefore, the size of chamfer R on the root bottomof the roller＇s guide pillar has an important influence on the operating state of automatic spinning machine. In order to achieve the rapid, automatic and precise measurement of chamfer R on the root bottom of roller, an auto detection system }＇or roller~ s chamfer based on computer vision technology is proposed. Firstly, the principle of measurement based on computer vision technology is introduced. And then the extraction method of charnfer^s characteristic parameters is presented, which uses image processing technique to obtain these characteristic parameters by means of collected images of roller contour, including extraction of region of interest, extraction of subpixel precise edge, segmentation of arc and line, fittingof geometric primitives, etc. Finally, after experimental verification, the measurement error is within ＋ 5 μm and repeated accuracy is 0.1 pm. The results show that this measurement method is applicable to not only the chamfer on the textile workpiece, but also the workpieces of shaft type with various of sizes.

关键词： textile workpiece roller chamfer image measurement auto detection

chamfer Matching在CT和MRI图像匹配融合中的应用

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空军工程大学学报（自然科学版） 2001年第6期2卷 74-77页

作者：段锋童隆正吕振中空军工程大学工程学院陕西西安710038 首都医科大学北京100007

医学影像中的CT和MRI图像的精确匹配融合能为临床提供全面、丰富的诊断信息。文中首先对CT图像正常脑组织边缘做距离变换 ,形成距离图像 ,然后利用MRI图像正常脑组织边缘作为模板 ,实现了CT和MRI图像的精确匹配。在此基础上完成了CT和MR... 详细信息

医学影像中的CT和MRI图像的精确匹配融合能为临床提供全面、丰富的诊断信息。文中首先对CT图像正常脑组织边缘做距离变换 ,形成距离图像 ,然后利用MRI图像正常脑组织边缘作为模板 ,实现了CT和MRI图像的精确匹配。在此基础上完成了CT和MRI的信息融合。文中算法适用于CT和MRI的匹配 ,并对SPECT ,PET 。

关键词： chamfer Matching 距离变换匹配融合医学影像 CT图像 MRI图像

Thermal stress concentration points and stress mutations in nano-multilayer film structures

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Communications in Theoretical Physics 2025年第1期77卷 179-189页

作者： Ying Zheng Zhi You Wang Qianju Song Zao Yi Shubo Cheng Can Ma Chaojun Tang Qingdong Zeng Sohail Ahmad School of Mathematics and Science Joint Laboratory for Extreme Conditions Matter PropertiesThe State Key Laboratory of Environment-friendly Energy MaterialsTianfu Institute of Research and InnovationSouthwest University of Science and TechnologyMianyang 621010China School of Electronic Information and Electric Engineering Changsha UniversityChangsha 410022China School of Physics and Optoelectronic Engineering Yangtze UniversityJingzhouHubei 434023China School of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China Department of Oncology Sichuan Science City HospitalMianyangSichuan Province 621000China College of Science Zhejiang University of TechnologyHangzhou 310023China School of Physics and Electronic-information Engineering Hubei Engineering UniversityXiaogan 432000China Institute of Physics Bahauddin Zakariya UniversityMultan66000Pakistan

In the multilayer film-substrate system,thermal stress concentration and stress mutations cause film buckling,delamination and cracking,leading to device *** this paper,we investigated a multilayer film system composed of a substrate and three film *** thermal stress distribution inside the structure was calculated by the finite element method,revealing significant thermal stress differences between the *** is mainly due to the mismatch of the coefficient of thermal expansion between *** materials respond differently to changes in external temperature,leading to compression between *** are obvious thermal stress concentration points at the corners of the base layer and the transition layer,which is due to the sudden change of the shape at the geometric section of the structure,resulting in a sudden increase in local *** address this issue,we chamfered the substrate and added an intermediate layer between the substrate and the transition layer to assess whether these modifications could reduce or eliminate the thermal stress concentration points and extend the service life of the multilayer *** results indicate that chamfering and adding the intermediate layer effectively reduce stress discontinuities and mitigate thermal stress concentration points,thereby improving interlayer bonding strength.

关键词： multilayer structure thermal stress concentration point stress mutation chamfer intermediate layer

Slenderness Ratio Effect on the Eccentric Compression Performance of chamfered Laminated Bamboo Lumber Columns

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Journal of Renewable Materials 2022年第1期10卷 165-182页

作者： Ke Zhou Haitao Li Assima Dauletbek Dong Yang Zhenhua Xiong Rodolfo Lorenzo Kun Zhou Ileana Corbi Ottavia Corbi College of Civil Engineering Nanjing Forestry UniversityNanjing210037China Joint International Research Laboratory of Bio-Composite Building Materials and Structures Nanjing Forestry UniversityNanjing210037China Ganzhou Sentai Bamboo Company Ltd.Ganzhou341001China University College London LondonWC1E 6BTUK Guangxi Lvjing Bamboo Company Ltd. Guilin541402China University of Naples Federico II Naples80133Italy

Eccentric compression tests on 15 chamfered laminated bamboo lumber(LBL)columns with a height ranging from 600 to 3000 mm were conducted in order to study the eccentric mechanical *** failure of all specimens was caused by the crack of bamboo fiber in the tensile *** the ultimate strength was reached,except specimens with a height of 600 mm,all other specimens could bear large deformation,showing good *** lateral displacements of the specimens under eccentric compression were approximately para-bolic in the direction of column *** ultimate bending moment of LBL columns with different slenderness ratios under compression with the same initial eccentricity was a fixed *** relationship between ultimate capacity,axial displacement,lateral displacement,and slenderness ratio was analyzed based on test *** was found that the plane section assumption could be used to express the stress and strain distribution of chamfered LBL columns under eccentric compression.A method for calculating the ultimate bearing capacity was proposed using a constitutive model based on the Ramberg-Osgood relation and the empirical formula for calculating the ultimate capacity was given on the basis of the former research as well as the test results in this paper.

关键词： Laminated bamboo lumber column chamfer eccentric compression tangential

Mesh sharpening via normal filtering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 546-553页

作者： Jian-guo SHEN San-yuan ZHANG Zhi-yang CHEN Yin ZHANG Xiu-zi YE State Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China Software College Zhejiang University of Technology Hangzhou 310014 China

We present a robust mesh sharpening approach to reconstructing sharp features from blended or chamfered features, even with noise and aliasing errors. Feature regions were first recognized via normal variation according to the user's input, and then normal filtering was applied to faces of feature regions. Finally, the vertices of the feature region were gradually updated based on new face normals using a least-squares error criterion. Experimental results demonstrate that the method is effective and robust in sharpening meshes.

关键词： Normal filtering Sharp feature Mesh sharpening Blend chamfer

Design and field measurement of a dipole magnet for a newly developed superconducting proton cyclotron beamline

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Nuclear Science and Techniques 2018年第9期29卷 214-221页

作者： Jun-Sheng Zhang Jin-Xing Zheng Yun-Tao Song Wu-Quan Zhang Ming Li Xian-Hu Zeng Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230031China

The design, field quality optimization, multipole field analysis, and field measurement of a dipole for a newly developed superconducting proton cyclotron(SC200) beamline are presented in this paper. The maximum magnetic field of the dipole is 1.35 T; the bending radius is 1.6 m with a proton beam energy in the range of70–200 Me V. The magnetic field was calculated with 2 D and 3 D simulations, and measured with a Hall mapping system. The pole shim and end chamfer were optimized to improve the field quality. Based on the simulated results,the multipole field components in the good-field region were studied to evaluate the field quality. The results showed that the field quality is better than ± 5 × 10^(-4) at1.35 T with shimming and chamfering. For the transverse field homogeneity, the third-order(B3) and fifth-order(B5)components should be controlled with symmetrical *** second-order(B2) component was the main disturbance for the integral field homogeneity; it could be improved with an end chamfer. The magnet manufacturing and field measurement were performed in this project. The measurement results demonstrated that the magnetic design and field quality optimization of the 45° dipole magnet can achieve the desired high field quality and satisfy the physical requirements.

关键词： Magnet Field quality Pole shim End chamfer Multipole field component

Simplified parasitic capacitance extraction of shield in HVDC converter system with boundary element method

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Frontiers of Electrical and Electronic Engineering in China 2010年第4期5卷 505-509页

作者： Shili LIU Zezhong WANG Jing SUN Beijing Key Laboratory of High Voltage&EMC North China Electric Power UniversityBeijing 102206China

It is critical to build a wide-band circuit model to conduct research on the characteristics of the electromagnetic disturbance source during the localization of high voltage direct current(HVDC)*** capacitance is most essential for modeling the equivalent circuit,so a fast and accurate computation of capacitance parameters plays a vital *** of the large size and complex structure of the converter equipment,it is impossible to obtain capacitance parameters by means of measurement or simulating calculation with finite element *** this paper,a simplified method of capacitance extraction based on boundary element method is proposed,which can provide an efficient means of establishing simulation *** the method presented,simulation model of the shield may not be ***,the edge and corner of the shield do not need to be handled with a sphere,cylinder and other curved surface *** availability of this method is demonstrated by comparing the capacitance parameters of chamfered shield with that of non-chamfered shield.

关键词： parasitic capacitance shield chamfer boundary element method(BEM) simplified model extraction

Optimization of Magnetic Field for CR Dipole Magnet

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Chinese Physics C 2008年第z1期32卷 19-21页

作者：姚庆高马力祯何源李青吴巍卞文龙袁平詹文龙中国科学院近代物理研究所

High homogeneity of the CR (collector ring) dipole magnet for FAIR (Facility for Antiproton and Ion Research) project at GSI is *** two optimized and analysis methods are introduced in detail,In order to obtain an ideal integral magnetic field distribution,the complicated end chamfer has been *** chamfering the removable pole,the distribution tolerance of high magnetic field is optimized to±2×10^(-4).The method of adding a mirror plane is suitable for the high magnetic field and it doesn't fit the low *** OPERA is used to optimize the dipole magnetic field.

关键词： removable pole chamfer mirror plane optimization