检索结果-南通市图书馆

shape analysis of Bounded Traveling Wave Solutions and Solution to the Generalized Whitham-Broer-Kaup Equation with Dissipation Terms

引用

Chinese Annals of Mathematics,Series B 2012年第2期33卷 281-308页

作者： Weiguo ZHANG Qiang LIU Xiang LI Boling GUO School of Science University of Shanghai for Science and TechnologyShanghai 200093China Department of Mathematics and Information Science Zhengzhou University of Light IndustryZhengzhou 450002China Institute of Applied Physics and Computational Mathematics Beijing 100088China

This paper deals with the problem of the bounded traveling wave solutions' shape and the solution to the generalized Whitham-Broer-Kaup equation with the dissipation terms which can be called WBK equation for *** authors employ the theory and method of planar dynamical systems to make comprehensive qualitative analyses to the above equation satisfied by the horizontal velocity component u(ξ) in the traveling wave solution (u(ξ),H(ξ)),and then give its global phase *** authors obtain the existent conditions and the number of the solutions by using the relations between the components u(ξ) and H(ξ) in the *** authors study the dissipation effect on the solutions,find out a critical value r*,and prove that the traveling wave solution (u(ξ),H(ξ)) appears as a kink profile solitary wave if the dissipation effect is greater,i.e.,|r| ≥ r*,while it appears as a damped oscillatory wave if the dissipation effect is smaller,i.e.,|r| < r*.Two solitary wave solutions to the WBK equation without dissipation effect is also *** on the above discussion and according to the evolution relations of orbits corresponding to the component u(ξ) in the global phase portraits,the authors obtain all approximate damped oscillatory solutions (u(ξ),H(ξ)) under various conditions by using the undetermined coefficients ***,the error between the approximate damped oscillatory solution and the exact solution is an infinitesimal decreasing exponentially.

关键词： Generalized Whitham-Broer-Kaup equation shape analysis Solitarywave solution Damped oscillatory solution Error estimate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Theoretical shape analysis of tapered fibers using a movable large-zone furnace

引用

Optoelectronics Letters 2011年第2期7卷 154-157页

作者：孙伟民袁明曾宪金 T.A.Birks College of Science Harbin Engineering University Department of Physics University of Bath

To estimate the shape of tapered fibers using tapering machines with movable large-zone furnaces, a new calculation method is proposed based on the discrete deducing method and the principle of the volume conservation of the fiber materials. This method can estimate the tapering results, i.e., the shape of the tapered fibers, based on arbitrary moving parameters of the large-zone furnace and the fiber holders. The theoretical estimated results agree with the experimental measuring shape of the tapered fibers quite well.

关键词： Furnaces Calculation methods Fiber holders Fiber materials shape analysis Tapered fiber Volume conservation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An efficient numerical shape analysis for light weight membrane structures

引用

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2014年第4期15卷 255-271页

作者： Chao YANG Yan-bin SHEN Yao-zhi LUO Space Structures Research Center Zhejiang University Hangzhou 310058 China

The determination of initial equilibrium shapes is a common problem in research work and engineering applications related to membrane structures. Using a general structural analysis framework of the finite particle method （FPM）, this paper presents the first application of the FPM and a recently-developed membrane model to the shape analysis of light weight mem- branes. The FPM is rooted in vector mechanics and physical viewpoints. It discretizes the analyzed domain into a group of parti- cles linked by elements, and the motion of the free particles is directly described by Newton＇s second law while the constrained ones follow the prescribed paths. An efficient physical modeling procedure of handling geometric nonlinearity has been developed to evaluate the particle interaction forces. To achieve the equilibrium shape as fast as possible, an integral-form, explicit time integration scheme has been proposed for solving the equation of motion. The equilibrium shape can be obtained naturally without nonlinear iterative correction and global stiffness matrix integration. Two classical curved surfaces of tension membranes pro- duced under the uniform-stress condition are presented to verify the accuracy and efficiency of the proposed method.

关键词： Tension membranes Finite particle method (FPM) shape analysis Explicit time integration Initial equilibriumshape

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A shape Graph Logic and A shape System

引用

Journal of Computer Science & Technology 2013年第6期28卷 1063-1084页

作者：李兆鹏张昱陈意云 CCF School of Computer Science and Technology University of Science and Technology of China Software Security Laboratory Suzhou Institute for Advanced StudyUniversity of Science and Technology of China

analysis and verification of pointer programs are still difficult problems so far. This paper uses a shape graph logic and a shape system to solve these problems in two stages. First, shape graphs at every program point are constructed using an analysis tool. Then, they are used to support the verification of other properties （e.g., orderedness）. Our prototype supports automatic verification of programs manipulating complex data structures such as splay trees, treaps, AVL trees and AA trees, etc. The proposed shape graph logic, as an extension to Hoare logic, uses shape graphs directly as assertions. It can be used in the analysis and verification of programs manipulating mutable data structures. The benefit using shape graphs as assertions is that it is convenient for acquiring the relations between pointers in the verification stage. The proposed shape system requires programmers to provide lightweight shape declarations in recursive structure type declarations. It can help rule out programs that construct shapes deviating from what programmers expect （reflected in shape declarations） in the analysis stage. As a benefit, programmers need not provide specifications （e.g., pre-/post-conditions, loop invariants） about pointers. Moreover, we present a method doing verification in the second stage using traditional Hoare logic rules directly by eliminating aliasing with the aid of shape graphs. Thus, verification conditions could be discharged by general theorem provers.

关键词： shape graph logic program verification shape analysis automated theorem proving loop invariant inference

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Crystal habit for upconversion laser crystal of BaY_2F_8

引用

Journal of Rare Earths 2008年第4期26卷 501-504页

作者：李广慧阮永丰张守超孙伟 School of Commerce Tianjin University of Commerce School of Science Tianjin University

BaY2F8 crystals had a relatively low symmetry, and its XRD data showed that those strong diffractions occured in a narrow angle range, so it was difficult to orientate the single crystals of BaYEFs. In this paper, based on the structure characteristics and XRD data, the crystal habit of BaY2F8 was analyzed. The strong bond in crystal structure of BaYEF8 was Y-FE-Y, which stretched to the shape of chain along the direction of [001]. And this was an advantaged direction for the crystal growth. The steady shapes of BaY2F8 were composed of rhombic prism { 130} and {021 }. The crystal showed an axial habit in the direction of [001]. The analysis of the crystal slice obtained by temperature gradient technique verified the above conclusion. The BaY2F8 crystal was grown by compulsive methods such as Czochralski method.

关键词： BaY2F8 crystal crystal structure crystal habit shape analysis rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Data driven composite shape descriptor design for shape retrieval with a VoR-Tree

引用

Applied Mathematics(A Journal of Chinese Universities) 2018年第1期33卷 88-106页

作者： WANG Zi-hao LIN Hong-wei XU Chen-kai School of Mathematical Science State Key Lab.of CAD&CG Zhejiang University

We develop a data driven method(probability model) to construct a composite shape descriptor by combining a pair of scale-based shape descriptors. The selection of a pair of scale-based shape descriptors is modeled as the computation of the union of two events, i.e.,retrieving similar shapes by using a single scale-based shape descriptor. The pair of scale-based shape descriptors with the highest probability forms the composite shape descriptor. Given a shape database, the composite shape descriptors for the shapes constitute a planar point set.A VoR-Tree of the planar point set is then used as an indexing structure for efficient query operation. Experiments and comparisons show the effectiveness and efficiency of the proposed composite shape descriptor.

关键词： shape descriptor shape retrieval shape analysis data-driven model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

BOUNDED TRAVELING WAVE SOLUTIONS OF VARIANT BOUSSINESQ EQUATION WITH A DISSIPATION TERM AND DISSIPATION EFFECT

引用

Acta Mathematica Scientia 2014年第3期34卷 941-959页

作者：张卫国刘强李正明李想 School of Science University of Shanghai for Science and Technology Department of Mathematics and Information Science the College of Zhengzhou Light Industry Business School University of Shanghai for Science and Technology

This article studies bounded traveling wave solutions of variant Boussinesq equation with a dissipation term and dissipation effect on them. Firstly, we make qualitative analysis to the bounded traveling wave solutions for the above equation by the theory and method of planar dynamical systems, and obtain their existent conditions, number, and general shape. Secondly, we investigate the dissipation effect on the shape evolution of bounded traveling wave solutions. We find out a critical value r^＊ which can characterize the scale of dissipation effect, and prove that the bounded traveling wave solutions appear as kink profile waves if ｜r｜≥ r^＊; while they appear as damped oscillatory waves if ｜r｜〈 r^＊. We also obtain kink profile solitary wave solutions with and without dissipation effect. On the basis of the above discussion, we sensibly design the structure of the approximate damped oscillatory solutions according to the orbits evolution relation corresponding to the component u（ξ） in the global phase portraits, and then obtain the approximate solutions （u（ξ）, H（ξ））. Furthermore, by using homogenization principle, we give their error estimates by establishing the integral equation which reflects the relation between exact and approximate solutions. Finally, we discuss the dissipation effect on the amplitude, frequency, and energy decay of the bounded traveling wave solutions.

关键词： Variant Boussinesq equation with dissipation term shape analysis bounded traveling wave solution error estimate dissipation effect

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Multi-Scale Salient Features for Analyzing 3D shapes

引用

Journal of Computer Science & Technology 2012年第6期27卷 1092-1099页

作者：杨永亮沈超慧 King Abdullah University of Science and Technology ThuwalSaudi Arabia Tsinghua National Lab for Informatics Science & Technology Tsinghua University

Extracting feature regions on mesh models is crucial for shape analysis and understanding. It can be widely used for various 3D content-based applications in graphics and geometry field. In this paper, we present a new algorithm of extracting multi-scale salient features on meshes. This is based on robust estimation of curvature on multiple scales. The coincidence between salient feature and the scale of interest can be established straightforwardly, where detailed feature appears on small scale and feature with more global shape information shows up on large scale. We demonstrate this kind of multi-scale description of features accords with human perception and can be further used for several applications as feature classification and viewpoint selection. Experiments exhibit that our method as a multi-scale analysis tool is very helpful for studying 3D shapes.

关键词： multi-scale salient feature shape analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Computer vision-aided DEM study on the compaction characteristics of graded subgrade filler considering realistic coarse particle shapes

引用

Railway Engineering Science 2024年第2期32卷 194-210页

作者： Taifeng Li Kang Xie Xiaobin Chen Zhixing Deng Qian Su Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China Department of Civil Engineering Central South UniversityChangsha 410075China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China

The compaction quality of subgrade filler strongly affects subgrade *** main objective of this research is to analyze the macro-and micro-mechanical compaction characteristics of subgrade filler based on the real shape of coarse ***,an improved Viola-Jones algorithm is employed to establish a digitalized 2D particle database for coarse particle shape evaluation and discrete modeling purposes of subgrade *** indexes of 2D subgrade filler are then computed and statistically ***,numerical simulations are performed to quantitatively investigate the effects of the aspect ratio(AR)and interparticle friction coefficient(μ)on the macro-and micro-mechanical compaction characteristics of subgrade filler based on the discrete element method(DEM).The results show that with the increasing AR,the coarse particles are narrower,leading to the increasing movement of fine particles during compaction,which indicates that it is difficult for slender coarse particles to inhibit the migration of fine ***,the average displacement of particles is strongly influenced by the AR,indicating that their occlusion under power relies on particle *** dis-placement and velocity of fine particles are much greater than those of the coarse particles,which shows that compaction is primarily a migration of fine *** the cyclic load,the interparticle friction coefficientμhas little effect on the internal structure of the sample;under the quasi-static loads,however,the increase inμwill lead to a significant increase in the porosity of the *** study could not only provide a novel approach to investigate the compaction mechanism but also establish a new theoretical basis for the evaluation of intelligent subgrade compaction.

关键词： Subgrade filler particles Deep learning particle shape analysis Particle library Compaction characteristics Discrete element method(DEM)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Stable Geodesic Surface Signatures

引用

Tsinghua Science and Technology 2012年第4期17卷 471-480页

作者： Min Zhang Wei Zeng Shiqing Xin Ying He Xianfeng Gu Department of Mathematics Zhejiang University Hangzhou 310058 China School of Computing and Information Sciences Florida International University Miami FL 33199 USA School of Computer Engineering Nanyang Technological University Singapore 639798 Department of Computer Science Stony Brook University Stony Brook NY 11794 USA

shape analysis plays a fundamental role in computer graphics. We present a novel global and intrinsic shape representation for shape analysis, called stable geodesic signature. It is based on the theory of stable closed geodesics and surface Ricci flow. We examine the surface by dynamically deforming it by metric design through Ricci flow, then we observe the behavior of the stable closed geodesics under the evolving Riemannian metrics. When a metric is deforming some stable geodesic loops will become unstable and shrink to points, or some geodesic loops may merge. The number of stable geodesics forms the signature, which is general for arbitrary surfaces. Experiments on a large amount of surfaces demonstrate the efficiency and efficacy of the stable geodesic signature for shape analysis

关键词： Ricci flow stable geodesic shape analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：