拓扑结构
- 与 拓扑结构 相关的网络例句 [注:此内容来源于网络,仅供参考]
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With respect to syntax, the roles of tagmeme in the structure of word and sentence and Chomsky's Generative-Transformational Grammar are discussed. The spatial relation theory and existing research achievements are investigated. Having noticed the shortage of the capability of topological and metrical relation in the description of spatial information structure, the author proposes Combinational Qualitative Geometry based on the two invariables under ordinary transformations, distance ratio and direction difference, the CQG-based spatial relation system between topological and metrical constraint is thus constructed, on which several spatial relations such as parallel, perpendicularity, co-linearity, sequence and direct neighborhood are derived. Based on extended theory of spatial relation, the language anamorphosis is analyzed from the aspects of phonetics, semantics and syntax. The mere geometric and formalized spatial relation is then integrated with concrete geographic ontology to accommodate richer and indicative spatial configuration of spatial information in the different geographic context. Finally a syntax framework for spatial information is put forward.
在语法结构方面,首先阐述了法位和法素在语法结构词法和句法中的地位和作用,以及Chomsky生成转换语法的核心内容;详细介绍了地理信息系统空间关系理论及现有的研究成果;在分析现有的拓扑关系和量度关系对空间信息结构描述能力不足的基础上,提出了基于长度比和角度差两个不变量的组合定性几何,以此建立了介于拓扑及量度约束之间的组合定性关系体系,并以此为基础派生出平行、垂直、共线、次序、直接邻近等空间关系描述;本文基于扩展的空间关系理论,详细讨论了空间关系在语音、语法和语义三个方面的语言变体,将纯几何和纯形式化的空间关系与具体的地理本体结合起来,可以获得更为丰富的、更能反映空间关系在不同语言上下文中具体体现的组合关系;最后给出了一个空间信息的语法结构的基本框架。
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This paper presents an IFMC CAD model that consits of a geometry model and a material model, in which the geometry space acts as a base space and the material space acts as a bundle space. In this CAD model, the geometry model is based on the non-manifold model. In addition, a half-face data sturucture, which is derived from the half-edge data structure with the non-manifold feature of IFMC taken into account, is adopted to represent the geometry and topology information of the component. For the material model of IFMC, this paper focuses on the FGM component representation firstly and present a simplex-subdivision based CAD data exchange format, in which the material information is represented as a (n-1) simplex and material distributing feature is represented by the interpolation on the simplex-subdivision. Based on those, a part-building orientation optimization algorithm and an adaptive slicing algorithm for FGM component are presented in the paper. For the IFMC material model, the IFMC material information representation is divided into a meso-scale and a macro-scale representation. In the meso-scale, a concept named parameterized periodic functional meso-structure is presented as a unique form to represent the FGM (the homogeneous materials are regarded as a special FGM), the composite and the functional meso-structure material. The model of PMS is a three-tuple that contains the space state informatation, the material parameter and the material meso-scale distribution feature. The macro-scale material information representation is similar to the FGM components by interpolation of the control parameter of the periodical functional meso-structure based on the simplex-subdivision. Through an example of manufacturing-oriented IFMC CAD data processing, it is proved that the IFMC CAD model and the material information representation and process method proposed in this paper can provide a reliable data support for IFMC digital concurrent design and manufacturing.
本文将理想材料零件CAD模型建立在以几何空间为底空间、以材料空间为丛空间的结构上,使用非流形几何模型作为理想材料零件几何拓扑模型的基础,并在半边数据结构基础上,针对理想材料零件的非流形特征局限内部边界上的特点,给出了一个半面数据结构来表述零件的几何拓扑信息;对于理想材料零件的材料模型,本文先从功能梯度材料零件的信息表述与CAD数据交换和处理入手,将材料信息表述为(n-1)维单纯形,然后通过对三维几何区域的单纯剖分,以插值的方式表述零件材料分布特征;在此基础上,根据功能梯度材料零件分层制造中对CAD数据处理的要求,给出了综合考虑零件几何特征与材料特征的生长方向优化算法和自适应切片算法;而对于文中所定义的理想材料零件,本文将其材料信息表述分解到细观和宏观两个尺度进行,首先给出了细观尺度上参数化的周期性功能细结构概念,以此来统一表述功能梯度材料(单质材料作为特殊的功能梯度材料看待)、复合材料和功能细结构材料;把周期性功能细结构模型化为一个包含空间状态信息、材料构成参数和材料细观分布特征参数的三元组,以表达零件的细观材料特征;对于零件宏观的材料变化特征,则同样在几何区域单纯剖分的基础上,通过对细观尺度上周期性功能细结构控制参数的插值来完成;通过理想材料零件CAD数据处理的算例,验证了本文中理想材料零件CAD模型及材料信息表述与处理方法完全可以为理想材料零件的数字化制造提供可靠的数据支持。
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This paper presents an IFMC CAD model that consits of a geometry model and a material model, in which the geometry space acts as a base space and the material space acts as a bundle space. In this CAD model, the geometry model is based on the non-manifold model. In addition, a half-face data sturucture, which is derived from the half-edge data structure with the non-manifold feature of IFMC taken into account, is adopted to represent the geometry and topology information of the component.For the material model of IFMC, this paper focuses on the FGM component representation firstly and present a simplex-subdivision based CAD data exchange format, in which the material information is represented as a (n-1) simplex and material .distributing feature is represented by the interpolation on the simplex-subdivision. Based on those, a part-building orientation optimization algorithm and an adaptive slicing algorithm for FGM component are presented in the paper.For the IFMC material model, the IFMC material information representation is divided into a meso-scale and a macro-scale representation. In the meso-scale, a concept named parameterized periodic functional meso-structure is presented as a unique form to represent the FGM (the homogeneous materials are regarded as a special FGM), the composite and the functional meso-structure material. The model of PMS is a three-tuple that contains the space stateinformatation, the material parameter and the material meso-scale distribution feature. The macro-scale material information representation is similar to the FGM components by interpolation of the control parameter of the periodical functional meso-structure based on the simplex-subdivision.Through an example of manufacturing-oriented IFMC CAD data processing, it is proved that the IFMC CAD model and the material information representation and process method proposed in this paper can provide a reliable data support for IFMC digital concurrent design and manufacturing.
本文将理想材料零件CAD模型建立在以几何空间为底空间、以材料空间为丛空间的结构上,使用非流形几何模型作为理想材料零件几何拓扑模型的基础,并在半边数据结构基础上,针对理想材料零件的非流形特征局限内部边界上的特点,给出了一个半面数据结构来表述零件的几何拓扑信息;对于理想材料零件的材料模型,本文先从功能梯度材料零件的信息表述与CAD数据交换和处理入手,将材料信息表述为(n-1)维单纯形,然后通过对三维几何区域的单纯剖分,以插值的方式表述零件材料分布特征;在此基础上,根据功能梯度材料零件分层制造中对CAD数据处理的要求,给出了综合考虑零件几何特征与材料特征的生长方向优化算法和自适应切片算法;而对于文中所定义的理想材料零件,本文将其材料信息表述分解到细观和宏观两个尺度进行,首先给出了细观尺度上参数化的周期性功能细结构概念,以此来统一表述功能梯度材料(单质材料作为特殊的功能梯度材料看待)、复合材料和功能细结构材料;把周期性功能细结构模型化为一个包含空间状态信息、材料构成参数和材料细观分布特征参数的三元组,以表达零件的细观材料特征;对于零件宏观的材料变化特征,则同样在几何区域单纯剖分的基础上,通过对细观尺度上周期性功能细结构控制参数的插值来完成;通过理想材料零件CAD数据处理的算例,验证了本文中理想材料零件CAD模型及材料信息表述与处理方法完全可以为理想材料零件的数字化制造提供可靠的数据支持。
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This paper discusses the kernel of the system -- geometric model and includes the following:(1) The topological elements and the relation between them in geometric modeling system are explained and expressed by the theory of simplicial complex and CW-complex. In addition, the identification operators and homology theory in algebraic topology are used in our model. A hierarchical structure is built on the base of complex.
本文主要讨论这个系统的核心问题——几何建模问题,包括以下几个方面内容:(1)用单纯复形和CW复形的理论来解释和表达造型系统中的拓扑元素和拓扑元素之间的相关关系,并将代数拓扑中的粘合操作和同调论应用到模型中,建立以复形为基础的层次结构。
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In this dissertation, incorporating the level set algorithm, the gradient projection method, the nonlinear mapping technique, the return mapping algorithm and the mean curvature flow technique into topological optimization theory, a level set algorithm for topology optimization with multi-material structures is put forward, which can optimize a problem with general objective functions, multi-constraints, multi-materials and multi-load cases.
同时,又将拓扑导数理论和水平集算法结合起来,提出了结构拓扑优化的拓扑导数与水平集算法,进一步提高了计算效率。
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The arcs which are joined in the same node are ordered by means of bina sorting tree, and the minimal polygons are built by the right sequence of arcs, then polygon overlaying is finished.
通过在无拓扑矢量数据中局部引入拓扑关系,对同一结点连接的弧段,采用二叉树方法进行排序,构建最小多边形,完成无拓扑信息的矢量图形的重组,并对新算法与已有算法的结构进行了对比。
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Local topological information is imported to the altered polygon in this new algorithm.The arcs which are joined in the same node are ordered by means of bina sorting tree,and the minimal polygons are built by the right sequence of arcs,then polygon overlaying is finished.
通过在无拓扑矢量数据中局部引入拓扑关系,对同一结点连接的弧段,采用二叉树方法进行排序,构建最小多边形,完成无拓扑信息的矢量图形的重组,并对新算法与已有算法的结构进行了对比。
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Furthermore, in order to greatly improve computational efficiency, another topological optimization method, named as a topological derivative and level set algorithm for topology optimization, is also proposed by unifying topological derivative theory with the level set method.
同时,又将拓扑导数理论和水平集算法结合起来,提出了结构拓扑优化的拓扑导数与水平集算法,进一步提高了计算效率。
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In chapter 1, an up to now synthetically evaluation is given on the research ways and conclusions about jet in cross-flow. Considering the shortage of previous research ways and techniques (the instantaneous flow field and vortices field can not be properly get), in addition to the deficiency of corresponding conclusion (mainly concentrate on the analysis of time-average but little on structures of flow and action of vortex), the research way and content is draft out in this part. Though PIV, the time-average, instantaneous flow field and vortices field can be get, that will unveil the coherent vortex and its course of generation, development and evolvement, with the assistance of K-ε model and Hybrid Finite Analytic Method , which will proof-test the experiment result and bring some complementary, more profound research about the 3-D characters can be done. Using some fundamental topological theory and principle on flow analysis, with anglicizing of vortex structure, a reasonable description is the topological characteristic of near field in JICF given.
首先在第一章中对横流中湍射流的以往研究方法和研究成果给予了综合的评述,针对横流中湍射流旋涡结构以往研究中研究方法的局限性(不能很好得到流动的瞬态流场及涡量场)和相应研究成果中存在的不足(大都集中在时均特性的分析,对流动的内部结构和旋涡的运动阐述很少),明确了本文的研究方法和研究内容:通过PIV流动测量显示技术得到流动的时均及瞬态流场、涡量场,来揭示横流中湍射流的时均、瞬态流场、涡量分布特性,和各种具有拟序结构性质的复杂涡系的产生、发展及演化过程;结合湍流k-ε双方程模型及相应的HFAM计算方法,对于实验进行相互验证和补充,从而更为充分地研究各种旋涡的三维特性;利用拓扑分析的一些基本原理及相关规则,依据对各种旋涡结构的分析,做出对射流近区流场拓扑性质的合理描述。
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In order to indicate the difference in the molecular structures,the reduced topological index is defined,which is the ratio of the topological index of a molecule and that of the n...
为更突出地表达分子间的结构差异,定义了对比拓扑指数,即烷烃分子的拓扑指数与同碳数正构烷烃的拓扑指数之比。
- 推荐网络例句
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According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.
曝气设备的动力效率在叶轮转速为120rpm~150rpm时取得最大值,此时氧利用率和充氧能力也具有较高值。
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The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.
稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世,形体几无变化。
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When I was in school, the rabbi explained everythingin the Bible two different ways.
当我上学的时候,老师解释《圣经》用两种不同的方法。