检索结果-南通市图书馆

湘潭大学自然科学学报 2013年第4期35卷 93-96页

作者：唐少辉 ma y s 广东工业大学机电工程学院广东广州510090 阿尔伯塔大学机械系

并行和协同产品设计环境中,参与协同的多应用间信息共享的核心是基于网络的数据源.该文提出在煤矿机械企业采用基于单元模型、面向特征的产品数据库,以实现特征操作驱动与历史无关的模型重建.

关键词：面向特征单元模型协同设计

在线全文

学校读者我要写书评

暂无评论

基于单元模型的CAx集成研究

机械设计 2009年第9期26卷 4-7页

作者：唐少辉 ma y s Chen G 广东工业大学机电工程学院广东广州510641 加拿大阿尔伯塔大学机械系加拿大爱德蒙顿ABT6G2G8 新加坡南洋理工大学机械与航空系新加坡639798

并行和协同式产品设计已经成为当前流行的设计模式。在并行和协同设计环境中,为了实现信息共享和多应用之间模型改变的传递,提出了基于单元模型的多应用集成方法。在分析单元模型的数据结构和基于单元模型的特征造型方法特点的基础上,... 详细信息

并行和协同式产品设计已经成为当前流行的设计模式。在并行和协同设计环境中,为了实现信息共享和多应用之间模型改变的传递,提出了基于单元模型的多应用集成方法。在分析单元模型的数据结构和基于单元模型的特征造型方法特点的基础上,应用实例说明如何应用单元模型实现CAD/CAM的集成。

关键词：单元模型 CAx 集成

在线全文

学校读者我要写书评

暂无评论

与历史无关的模型重建中基于规则的特征排序

机械设计 2008年第7期25卷 60-62页

作者：唐少辉 ma y s Chen G 广东工业大学机电工程学院广东广州510006 加拿大阿尔伯塔大学机械系加拿大爱德蒙顿ABT6G2G8 新加坡南洋理工大学机械与宇航工程学院新加坡639798

动态维护模型中特征的顺序是与历史无关模型重建方法的关键。文中提出并应用基于规则的方法,在造型过程中产生唯一的特征顺序。文中描述并着重应用实例详细分析所提出的规则。最后给出产生特征顺序的算法,并用实例来进行分析验证。

关键词：特征与历史无关模型重建基于规则

面向特征的产品数据库中并行性和一致性的控制

在线全文

学校读者我要写书评

暂无评论

机械设计 2008年第10期25卷 43-45页

作者：唐少辉 ma y s Chen G 广东工业大学机电工程学院广东广州510090 加拿大阿尔伯塔大学机械系新加坡南洋理工大学机械与航空系新加坡639798

并行和协同式产品设计已经成为当前的流行设计模式。具有粒度的产品数据库是理想的支持基于网络的协同式设计数据源。文中重点讨论产品数据库中如何管理数据颗粒。应用所提出的方法,能保证产品数据库中特征模型的并行性和一致性。

关键词：面向特征数据库协同设计并行性一致性

在线全文

学校读者我要写书评

暂无评论

面向特征的产品数据库中特征有效性的维护

机械设计与制造 2008年第8期 200-202页

作者：唐少辉 ma，y．s． Chen，G．广东工业大学机电工程学院广州510090 加拿大阿尔伯塔大学机械系爱德蒙顿AB T6G 2G8 新加坡南洋理工大学机械与宇航工程学院新加坡639798

并行和协同产品设计已经成为当前的流行设计模式。具有粒度的产品数据库是理想的支持基于网络的协同设计数据源。重点讨论如何维护面向特征的数据库中产品特征模型的有效性。应用所提出的约束解决方法,能保证产品数据库中特征模型的有... 详细信息

并行和协同产品设计已经成为当前的流行设计模式。具有粒度的产品数据库是理想的支持基于网络的协同设计数据源。重点讨论如何维护面向特征的数据库中产品特征模型的有效性。应用所提出的约束解决方法,能保证产品数据库中特征模型的有效性以支持多应用产品协同设计。

关键词：面向特征数据库特征有效性约束条件协同工程

Identifiability and sloppiness of structured systems with a matrix fraction description using finite frequency responses

在线全文

学校读者我要写书评

暂无评论

science China(Information sciences) 2025年第2期68卷 200-215页

作者： yunxiang ma Tong ZHOU Department of Automation Tsinghua University Department of Automation and BNRist Tsinghua University

This paper investigates the identifiability of structured systems with a matrix fraction description and attacks practical difficulties in estimating parameters under finite frequency responses. The numerator and denominator polynomial matrices depend affinely on system parameters, which can represent a broad range of systems, especially circuits and mechanical systems. Except for assuming that the denominator matrix is invertible, no further assumptions are adopted. A criterion is provided for validating this assumption utilizing graph theories and matroids. A sufficient and necessary criterion for global identifiability based on the rank of a numerical matrix is given and can be recursively verified with each frequency point,which is computationally attractive for large-scale systems. For an identifiable system, an ellipsoid approximation is obtained for the set of parameters whose corresponding system frequency responses deviate within a specific range from those of the system at a specific parameter value. Using this approximation, explicit expressions for absolute and relative sloppiness have been derived, which can be used to quantify the difficulty of identifying system parameters. Comparisons with the well-known Fisher information matrix have also been performed through a mechanical system, revealing significant differences in quantifying parameter estimation hardness.

关键词： identifiability sloppiness structured system matrix fraction graph theory matroid

同方期刊数据库

Global Dynamics of a Kawasaki Disease Vascular Endothelial Cell Injury Model with Backward Bifurcation and Hopf Bifurcation

在线全文

学校读者我要写书评

暂无评论

Acta mathematicae Applicatae sinica 2025年第1期41卷 200-233页

作者： Ke GUO Wan-biao ma school of mathematics and Physics University of Science and Technology BeijingBeijing 100083China

Kawasaki disease(KD)is an acute,febrile,systemic vasculitis that mainly affects children under five years of *** this paper,we propose and study a class of 5-dimensional ordinary differential equation model describing the vascular endothelial cell injury in the lesion area of *** model exhibits forward/backward *** is shown that the vascular injury-free equilibrium is locally asymptotically stable if the basic reproduction number R_(0)ypes of sufficient conditions for the global asymptotic stability of the vascular injury-free equilibrium,which can be applied to both the forward and backward bifurcation *** addition,the local and global asymptotic stability of the vascular injury equilibria and the presence of Hopf bifurcation are *** is also shown that the model is permanent if the basic reproduction number R_(0)>1,and some explicit analytic expressions of ultimate lower bounds of the solutions of the model are *** results suggest that the control of vascular injury in the lesion area of KD is not only correlated with the basic reproduction number R_(0),but also with the growth rate of normal vascular endothelial cells promoted by the vascular endothelial growth factor.

关键词： Kawasaki disease model backward bifurcation Hopf bifurcation global stability permanence

Conversion-type cathode materials for high energy density solid-state lithium batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 409-425页

作者： yuhao ma shihong Qing Hongyu Liu Chuntao ma yuan yu Chuang yu Liping Wang school of materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina Zhejiang Provincial Key Laboratory of Fiber materials and manufacturing Technology Zhejiang Sci-Tech UniversityHangzhou 310018ZhejiangChina state Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

solid-state lithium batteries(ssLBs)are regarded as an essential growth path in energy storage systems due to their excellent safety and high energy *** particular,ssLBs using conversion-type cathode materials have received widespread attention because of their high theoretical energy densities,low cost,and *** the great progress in research and development of ssLBs based on conversiontype cathodes,their practical applications still face challenges such as blocked ionic-electronic migration pathways,huge volume change,interfacial incompatibility,and expensive processing *** review focuses on the advantages and critical issues of coupling conversion-type cathodes with solid-state electrolytes(ssEs),as well as state-of-the-art progress in various promising cathodes(e.g.,Fes_(2),Cus,FeF_(3),FeF_(2),and s)in ***,representative research on conversion-type solid-state full cells is discussed to offer enlightenment for their practical ***,the energy density exhibited by the s cathode stands out impressively,while sulfide ssEs and halide ssEs have demonstrated immense potential for coupling with conversion-type ***,perspectives on conversion-type cathodes are provided at the material,interface,composite electrode,and battery levels,with a view to accelerating the development of conversion-type cathodes for high-energy–density ssLBs.

关键词： Conversion-type cathode Lithium-free cathode solid-state electrolyte solid-state lithium battery High energy density

Bandgap characteristics analysis and graded design of a novel metamaterial for flexural wave suppression

在线全文

学校读者我要写书评

暂无评论

Applied mathematics and Mechanics(English Edition) 2025年第1期46卷 1-24页

作者： Fan yANG Zhaoyang ma Xingming GUO shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai University shanghai Institute of Aircraft Mechanics and Control

A novel elastic metamaterial is proposed with the aim of achieving lowfrequency broad bandgaps and bandgap regulation. The band structure of the proposed metamaterial is calculated based on the Floquet-Bloch theorem, and the boundary modes of each bandgap are analyzed to understand the effects of each component of the unit cell on the bandgap formation. It is found that the metamaterials with a low elastic modulus of ligaments can generate flexural wave bandgaps below 300 Hz. Multi-frequency vibrations can be suppressed through the selective manipulation of bandgaps. The dual-graded design of metamaterials that can significantly improve the bandgap width is proposed based on parametric studies. A new way that can regulate the bandgap is revealed by studying the graded elastic modulus in the substrate. The results demonstrate that the nonlinear gradient of the elastic modulus in the substrate offers better bandgap performance. Based on these analyses, the proposed elastic metamaterials can pave the way for multi-frequency vibration control, low-frequency bandgap broadening, and bandgap tuning.

关键词： flexural wave bandgap graded design local resonance metamaterial O421+.5

Recent advances in exploring new blood-based biomarkers for the early diagnosis of gastric cancer

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

science China Chemistry 2025年第1期68卷 35-45页

作者： Xinyu Peng Qian ma Da Han school of Life science Shanghai UniversityShanghai 200444China Institute of Molecular Medicine Shanghai Key Laboratory for Nucleic Acid Chemistry and NanomedicineState Key Laboratory of Oncogenes and Related GenesRenji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200025China Department of Research and Development Intellinosis Biotechnologies Co.Ltd.Shanghai 201112China

Gastric cancer(GC)is a prevalent and lethal malignancy worldwide,and the 5-year survival rate is less than 30%.The absence of distinctive symptoms often leads to late-stage diagnosis,contributing to a grim *** detection is pivotal for improving the survival rates and outcomes of GC *** diagnostic methods,including gastroscopy and histopathological examination,are restricted in the early diagnosis of *** protein biomarkers,such as carcinoembryonic antigen(CEA),carbohydrate antigen 19-9(CA19-9),and carbohydrate antigen 72-4(CA72-4),exhibit insufficient sensitivity and specificity for GC screening,which diminishes their clinical ***,novel circulating biomarkers,such as circulating tumor cells(CTCs),circulating tumor cell DNA(ct DNA),and circulating free RNA(cf RNA),have emerged as promising candidates in the burgeoning field of liquid biopsy due to their superior sensitivity and *** review focuses on the latest research on blood-based biomarkers for GC diagnosis and examines the clinical potentials and challenges associated with these emerging biomarkers.

关键词： gastric cancer early diagnosis blood