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基于点云的铣刀螺旋槽截面预测模型

工具技术 2024年第4期58卷 96-100页

作者：张富能林志伟程思元薛勇傅建中浙江大学制造技术及装备自动化研究所杭州市310027

基于点云离散的思想,将铣刀棒料离散为点云集合,将砂轮简化为回转面及中心矢量表达的二维模型,建立判断棒料截面点云与砂轮回转面是否包含的磨削切除预测模型,并利用预测截面点云集合计算螺旋槽相关参数。采用OCC建立实际仿真磨削的点... 详细信息

基于点云离散的思想,将铣刀棒料离散为点云集合,将砂轮简化为回转面及中心矢量表达的二维模型,建立判断棒料截面点云与砂轮回转面是否包含的磨削切除预测模型,并利用预测截面点云集合计算螺旋槽相关参数。采用OCC建立实际仿真磨削的点云切除过程模块,实现对预测螺旋槽截面的显示以及结构参数的精确计算。通过改变砂轮结构位置参数,给出螺旋槽截面相关参数变化规律,并对其中具体实例进行了结果显示。

关键词：点云回转面中心矢量预测模型仿真磨削

含碳高硅矿球团在H_(2)-H_(2)O-N_(2)和CO-CO_(2)-N_(2)气氛下还原过程研究

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江西冶金 2024年第2期44卷 71-80页

作者：马立群程思远唐惠庆北京科技大学绿色低碳钢铁冶金全国重点实验室北京100083

针对高炉炼铁节能减排的新要求,在H_(2)-H_(2)O-N_(2)和CO-CO_(2)-N_(2)气氛下研究碳复合团块的反应行为。通过化学分析法、X射线衍射(XRD)和扫描电子显微镜-能谱(SEM-EDS)分析了复合团块的成分、矿相及微观形貌,对CO-CO_(2)-N_(2)和H_(... 详细信息

针对高炉炼铁节能减排的新要求,在H_(2)-H_(2)O-N_(2)和CO-CO_(2)-N_(2)气氛下研究碳复合团块的反应行为。通过化学分析法、X射线衍射(XRD)和扫描电子显微镜-能谱(SEM-EDS)分析了复合团块的成分、矿相及微观形貌,对CO-CO_(2)-N_(2)和H_(2)-H_(2)O-N_(2)气氛下碳复合团块的还原行为进行了分析,并建立了复合团块反应动力学模型。结果表明,在1 073、1 173、1 273、1 373 K温度下,复合团块在H_(2)-H_(2)O-N_(2)气氛下的还原度和碳气化率均高于CO-CO_(2)-N_(2)气氛。对2种气氛下含碳团块在1 273 K时的反应过程进行分析,XRD图谱表明,在H_(2)-H_(2)O-N_(2)气氛下反应20 min后,团块中FeO相消失;在CO-CO_(2)-N_(2)气氛下,一直存在团块中FeO相,说明复合团块在H_(2)-H_(2)O-N_(2)气氛下还原性更好。对比2种气氛下的扫描电子显微镜(SEM)照片,当反应进行到25 min时,金属铁在复合团块边缘大量聚集。综合考虑气固相之间化学反应的质量守恒和传质行为,建立复合团块反应动力学模型。结合实验结果进行分析,模型拟合结果较好。

关键词：复合团块还原气氛还原行为

Mechanism of capture section affecting an intake for atmosphere-breathing electric propulsion

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Chinese Journal of Aeronautics 2024年第1期37卷 51-63页

作者： siyuan ZHANG Jinyuan YANG cheng LI Haolin LI Liwei ZHANG Liang DING Anbang SUN State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi’an Jiaotong UniversityXi’an 710049China China Academy of Aerospace Science and Innovation Beijing 100049China

Atmosphere-Breathing Electric Propulsion(ABEP)can compensate for lost momentum of spacecraft operating in Very Low Earth Orbit(VLEO)which has been widely concerned due to its excellent commercial *** is a key technology to improve the capture efficiency of intakes,which collect and compress the atmosphere for *** this paper,the mechanism of the capture section affecting capture efficiency is investigated by Test Particle Monte Carlo(TPMC)simulations with 3D intake *** inner surface smoothness and average collision number are determined to be key factors affecting capture efficiency,and a negative effect growth model is accordingly *** the inner surface smoothness is less than 0.2,the highest capture efficiency and its corresponding average collision number interval are independent of the capture section’s geometry and its mesh *** the inner surface smoothness is higher than 0.2,the capture efficiency will decrease by installing any capture *** on the present results,the manufacturing process and material selection are suggested to be prioritized during the intake geometry design in engineering ***,the highest capture efficiency can be achieved by adjusting the length and mesh size of the capture section.

关键词： Atmosphere-breathing electric propulsion Capture efficiency Capture section Intake Test particle Monte Carlo Very low earth orbit

Regular Posit ion-Oriented Method for Mesh Smoothing

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Acta Mechanica Solida Sinica 2021年第3期34卷 437-448页

作者： Yongqing Hai Yufei Guo siyuan cheng Yunpeng Hai Department of Mechanics and Engineering Science Peking UniversityBeijing 100871China X Lab Second Academy of China Aerospace Science and Industry CorporationBeijing 100854China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China A College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266061China

Mesh smoothing is an essential technique for the improvement of mesh quality in finite element analysis,due to the fact that mesh quality has a large impact on the convergence of the computational scheme and the accuracy of the numerical results.A novel mesh smoothing method based on regular-position-guided operations is presented in this *** method introduced here contains two main stages:The first stage computes the regular position of each vertex based on the shape of the element and conducts regular-position-oriented-based element transformations independently;the second stage determines the finial position of each vertex according to its surrounding elements with an assembly *** method is not limited to planar triangular mesh,but applicable to surface polygonal *** experiments on various mesh models demonstrate the effectiveness and potential of this method.

关键词： Mesh smoothing Element transformation Finite element analysis Mesh quality

化学沉淀法的醇水比对氧化锌压敏电阻性能的影响研究

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电瓷避雷器 2024年第2期 51-57页

作者：董曼玲王博闻郭磊程思远姚伟王伟詹振宇国网河南省电力公司电力科学研究院郑州450052 湖南省湘电试研技术有限公司长沙410129

通过化学沉淀法制备得到ZnO压敏电阻样品并分析研究了样品的显微结构特性、宏观电学参量和介电响应特性,包括阻抗谱和介电损耗谱。采用XRD和SEM观测分析了ZnO压敏电阻的物相组成和微观结构。电学参数测试结果表明,当化学沉淀法的醇水比... 详细信息

通过化学沉淀法制备得到ZnO压敏电阻样品并分析研究了样品的显微结构特性、宏观电学参量和介电响应特性,包括阻抗谱和介电损耗谱。采用XRD和SEM观测分析了ZnO压敏电阻的物相组成和微观结构。电学参数测试结果表明,当化学沉淀法的醇水比为2∶1时,ZnO压敏电阻表现出的各项电性能均比较好:电压梯度为584.01 V/mm,非线性系数为73.43,泄漏电流为0.13μA/cm^(2)。该结果表明化学沉淀法可以作为制造高性能ZnO压敏电阻的有效途径。另外,通过介电谱的测试结果可以看出,介电损耗峰的峰值能体现出ZnO压敏陶瓷中缺陷的浓度,改变化学共沉淀法中的醇水比能够相应地改变ZnO压敏陶瓷中本征点缺陷的浓度。

关键词：氧化锌电阻片化学沉淀法晶界势垒高度

RECONSTRUCTION OF LAYER DATA WITH DEFORMABLE B-SPLINES

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Chinese Journal of Mechanical Engineering 2005年第3期18卷 321-324页

作者： cheng siyuan Zhang Xiangwei Xiong Hanwei Faculty of Electromechanical Engineering Guangdong University of Technology Guangzhou 510090 China

A new B-spline surface reconstruction method from layer data based on deformable model is presented. An initial deformable surface, which is represented as a closed cylinder, is firstly given. The surface is subject to internal forces describing its implicit smoothness property and external forces attracting it toward the layer data points. And then finite element method is adopted to solve its energy minimization problem, which results a bicubic closed B-spline surface with C^2 continuity. The proposed method can provide a smoothness and accurate surface model directly from the layer data, without the need to fit cross-sectional curves and make them compatible. The feasibility of the proposed method is verified by the experimental results.

关键词： Revere engineering Surface reconstruction Deformable model Layer data

HUNK inhibits cargo uptake and lysosomal traffic in the caveolar pathway via the AGAP3/ARF6

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Science Bulletin 2024年第2期69卷 173-178页

作者： siyuan Jiang Xiaoqi Han Tihui Liu Ying He Zidong Zhao Tongfeng Liu Shuwen cheng Jihang Zhang Liqiang Duan Yajuan Liu Tianyou cheng Yong Liu Qinong Ye Shan Gao Zhongda Hospital Medical SchoolAdvanced Institute for Life and HealthSoutheast UniversityNanjing 20096China Medical School of Guizhou University Guiyang 550025China Shanxi Academy of Advanced Research and Innovation Taiyuan 030032China Zhongda Hospital School of Life Sciences and TechnologyAdvanced Institute for Life and HealthSoutheast UniversityNanjing 210096China Nanjing University Medical School Nanjing 210046China Hubei Key Laboratory of Cell Homeostasis College of Life SciencesTaiKang Center for Life and Medical SciencesWuhan UniversityWuhan 430072China Department of Medical Molecular Biology Beijing Institute of BiotechnologyCollaborative Innovation Center for Cancer MedicineBeijing 100850China

Endocytosis is a crucial cellular process that takes up cargos by enclosing them in membrane-bound vesicles,and transports cargos to different parts of the cell,such as the lysosomes[1].Endocytosis is classified into several mechanistically and morphologically pathways,including clathrin-mediated endocytosis(CME)and caveolae-mediated endocytosis(CavME)[1,2].

关键词： endocytosis cargo uptake

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海岸线变化的单链曼延编号快速匹配方法

测绘学报 2022年第8期51卷 1817-1825页

作者：成思远张英翟亮中国测绘科学研究院自然资源调查监测研究中心北京100036 自然资源部测绘科学与地球空间信息技术重点实验室北京100036

受海岸带区域自然环境变迁与人类开发活动的综合影响,海岸线不断发生剧烈变化。发现海岸线变化并将变化前后的岸段进行匹配,对分析海岸线变化至关重要。针对传统空间分析工具难以直接确定不同时相变化岸段的对应关系的问题,本文引入单... 详细信息

受海岸带区域自然环境变迁与人类开发活动的综合影响,海岸线不断发生剧烈变化。发现海岸线变化并将变化前后的岸段进行匹配,对分析海岸线变化至关重要。针对传统空间分析工具难以直接确定不同时相变化岸段的对应关系的问题,本文引入单链曼延编号的思想对海岸线变化进行快速匹配,并按照“一对一”和“多对多”两种变化岸段匹配关系提出了位置变迁、类型转移、消失及新增等海岸线变化类型的判断公式,设计并实现了结合单链曼延编号的海岸线变化匹配与信息存储方法。试验证明,该方法能快速准确地实现海岸线变化匹配,并能很好地解决多对多变化岸段匹配的问题。

关键词：单链蔓延编号海岸线变化匹配方法变化类型

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DRNet:Towards fast,accurate and practical dish recognition

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Science China(Technological Sciences) 2021年第12期64卷 2651-2661页

作者： cheng siyuan CHU BinFei ZHONG BiNeng ZHANG ZiKai LIU Xin TANG ZhenJun LI XianXian Guangxi Key Lab of Multi-Source Information Mining&Security Guangxi Normal UniversityGuilin 541004China Department of Computer Science and Technology Huaqiao UniversityXiamen 361021China Seetatech Technology Nanjing 211800China

Existing algorithms of dish recognition mainly focus on accuracy with predefined classes,thus limiting their application *** this paper,we propose a practical two-stage dish recognition framework(DRNet)that yields a tradeoff between speed and accuracy while adapting to the variation in class *** the first stage,we build an arbitrary-oriented dish detector(AODD)to localize dish position,which can effectively alleviate the impact of background noise and pose *** the second stage,we propose a dish reidentifier(DReID)to recognize the registered dishes to handle uncertain *** further improve the accuracy of DRNet,we design an attribute recognition(AR)module to predict the attributes of *** attributes are used as auxiliary information to enhance the discriminative ability of ***,pruning and quantization are processed on our model to be deployed in embedded ***,to facilitate the study of dish recognition,a well-annotated dataset is *** AODD,DReID,AR,and DRNet run at about 14,25,16,and 5 fps on the hardware RKNN 3399 pro,respectively.

关键词： neural network acceleration neural network quantization object detection reidentification dish recognition