几何结构

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。

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。

Firstly, the author establish the functions of stability on the basis of the spline function method ,according to the theory of geometrical nonlinear and the theory of stability, educe the stability equation of structure based on variational principle, then carry through the flexuosity analysis of CFST arch.The big distortion geometrical nonlinear was considered by the stability equation,the author simplified the problem of geometrical nonlinear through ignored quadratic term and reserve the simple term, at last boiled down to solve the linear stability equation of eigenvalue .

利用样条函数方法、根据几何非线性变形理论和结构稳定性理论，先建立起结构稳定的泛函，再由变分原理导出结构的稳定方程，进行钢管混凝土拱屈曲分析；本文所建立的稳定方程考虑了几何非线性的大变形效应，通过忽略几何非线性的二次项，保留一次项，将几何非线性问题简化，最后归结为求解线性稳定问题的特征值稳定方程，建立了结构非线性静力稳定性问题的新算法及失稳类型判别准则。

With analyzing structure features of sheet metal parts, the geometrical information model is built on the basis of the hierarchy of structure feature, structure element and geometrical element.

2分析了钣金零件的结构特征构成，建立了"结构特征—结构要素—几何要素"的三层几何信息模型，并采用树结构组织模型几何数据，分别给出了框肋零件、整体壁板零件和蒙皮零件的几何信息模型；分析了状态衍化中的结构要素变化类型和成形工序对结构要素变化的影响，采用加权图描述了状态衍化中结构树的变化；对应零件几何信息层次构成，建立了钣金零件结构特征的XML模式，分别举例说明了各层几何信息的XML表达，形成了基于XML的钣金零件数据表达方法。

Because of special geometry structure of three-cone bit, the top of formation will form a tri-spine well bottom while drilling with three-cone bit the drill string. It is the tri-spine well bottom that leads to the axial harmonic of vibration when the bit revolves a round and the three concavo-convex heave of bit and formation result in one time (1×rpm),two time (2×rpm), three time (3×rpm) turning table speed.

高岩摘要：由于三牙轮钻头的特殊几何结构，钻进过程中在岩层顶部容易形成一个三脊状井底，正是这一三脊状井底，当钻头旋转一周时钻柱轴向三次凸凹变化，由此在轴向产生1倍、2倍和3倍及其更高次倍于转盘转速rpm的谐波振动。

ABF Value Converter also calculates the values of many mathematical functions, as well as makes it possible to conduct geometric constructions and calculations for some figures.

亚洲债券基金的价值也计算转换价值的许多数学函数，以及能够进行几何结构和计算一些数字。

This text passes to carry on several demarcations to the edge diagram, gathering the image to a set that means the shape orders the space relation of constant quantity characteristic.

其特点是，边缘提取不作为目标分割的手段，而仅视为反映图像几何结构分布的低层次特征。

Op Art expressed itself with reduced geometrical forms - sometimes in black and white contrasts and sometimes with very brilliant colors.

欧普艺术的元素仍是几何结构，有时利用黑白的反差，有时候追求光亮闪烁的特殊色彩效果。

To attaining longlived charge separated states, the new compounds 7 and 8 of C60-S-2-thioxo-1, 3-dithioles derivatives were synthesized by Diels-Alder cycloaddition reaction. The structures generated by AM1 were used as the initial configurations for the density functional optimization at the B3LYP/3-21G level for all carbon and sulfur clusters, and some geometry conformation indexes were obtained. We found that C60 has been half-packed by the curved 2-thioxo-1, 3-dithioles derivatives.

为了获得具有长寿命电荷分离态的[60]富勒烯－富硫衍生物有机功能分子，我们设计了用单键硫桥键联[60]富勒烯和硫酮衍生物的分子7和8，用半经验AM1方法得出最低能量的几何结构，在此基础上用密度泛函 B3LYP/3-21G方法，对其进行计算，得出电子相关的优化参数，预测其稳定性。

The study of clusters has become an interesting research in recent years, due to its particular geometric structures, unique physical and chemical properties and potential applications.

中文摘要：近年来，由于团簇具有特殊的几何结构和奇特的物理化学性质以及潜在的应用背景，因此引起人们的广泛关注。

The labia have now been sutured together almost completely.The drains and the Foley catheter come out at the top.

此刻阴唇已经几乎完全的缝在一起了，排除多余淤血体液的管子和Foley导管从顶端冒出来。

To get the business done, I suggest we split the difference in price.

为了做成这笔生意，我建议我们在价格上大家各让一半。