曲线的结点

In this paper, the method, which is based on the theory of envelope and continuous map, is investigated.

文中用此方法分析了一些曲线的重要几何性质，即曲线段上含有尖点、重结点和拐点以及不含这些点的用控制顶点相对位置表示的充分必要条件。

In this thesis, we apply Coulomb's law and propose an external force to overcome the problem of traditional ACM that can not capture the cavities of an object. Assume that each node of a snake has its own electric charge, and the object boundary has opposite electric charge. Then object boundary will attract the nodes of the snake. This helps the contour easily to move to the object boundary.

本论文中，我们运用库仑定律的观念，提出了一个运用局部引力作为外力的方法，用以克服传统主动性轮廓模型在凹面处收敛不佳的缺点；假设物件边界带电，而主动性轮廓模型的结点带与物件边界相异之电荷，则物件边界会吸引著主动性轮廓模型各结点，使得模型曲线更容易靠近物件边界。

With Hilbert space filling curve and latent semantic index, MLSQ maps similar data objects in high dimension semantic space into an adjacent range in one dimensional value space, and considers every data object sequence number in one dimensional space as a key. MLSQ distributes the keys to adjacent nodes of structured P2P systems. By embedding the process of searching data points of HSFC into the nodes of structured P2P networks and using the data search mechanism of networks, MLSQ can facilitate to search the data objects in accordance with query requirements.

该方法利用Hilbert空间填充曲线和潜在语义索引，将高维语义空间中相似的数据对象映射到一维数值空间中的邻近区域中，并以每个数据对象在一维数值空间中的序号作为键，将数据对象的索引分布到有组织P2P网络邻近的结点上，通过将HSFC中数据点的查找过程嵌入到有组织P2P网络的结点上，再利用网络的数据查找机制，MLSQ可方便地搜索到符合查询要求的数据对象。

Introduced is a kind of space uniform rational spline curve, which possesses tension parameters and is based on hyperbolic spline functions.

引入了基于双曲样条函数的、具有张力参数的空间有理等距节点样条参数曲线，给出了这种曲线在每个样条子区间上为挠曲线段的充分必要条件；分析了这种挠曲线段没有尖点、重结点和泛拐点的特性；因而在用于空间曲线几何造型时可避免奇异性。

Hence the study of geometric properties, which include the distribution of singular and inflection points and the convexity of parametric curves, is the key for designer to control the curves shape.

在计算机辅助几何设计的光顺曲线造型中，不希望曲线带有二重结点、尖点及多余拐点，因此对参数曲线的几何性质(包括奇、拐点分布及凸性等)的研究是控制其曲线形状的关键。

Through a typical Stamping example, compared and analyzed the node slip velocity curve and translational velocity curve. It proved the truth that the true loading rate simulating by Finite element software can reflect the slip velocity between sheet metal and die, providing the basis for the follow-up analysis in actual testing.

通过典型冲压成形实例，比较分析结点滑动速度和结点运动速度曲线，证明了有限元软件模拟的真实加载速度可以反映板料和模具之间的滑动速度，为后续的实际试验提供分析依据。

This conclusion corrects a mistaken resultIn the planar quadratic system there is not cubic algebraical saddle-nodeseparatrix-loop,in which the author asserrts that quadratic system has no the cubicalgebraical saddle-node separatrix cycle .

本文证明了平面二次系统的三次代数同宿轨线上可以存在鞍结点，并且二次系统可以存在含鞍结点的无返回映射三次曲线分界线环。

Thermodynamic properties of PSf - DMAc - alcohols ternary systems are studied, the binodal is calculated. Cloud point curves from light scattering experiment verify the calculation results; The agreement between the cloud point curves and the binodal is quite well.

文章摘要：对聚砜-二甲基乙酰胺-醇类非溶剂构成的制膜体系的热力学特性进行了研究，计算出这些体系的双结点线，并用这些醇类非溶剂通过光散射法进行浊点滴定实验，浊点曲线与双结点线基本重合，验证了双结点线的计算结果。

This thesis investigates the profile extraction and shape optimization on the result of topology optimization of planar compliant mechanisms. The main context includes the following work:(1) summarizing and analyzing the recent research status, some harvest and unsolved problems;(2) analyzing the conceptual design of planar path-generating compliant mechanisms and its mathematical model and tools;(3) Modifying the method of density contour as the method of profile extraction, and developing a method to optimize the density function in the profile extraction according to the requirement of the design of compliant mechanism;(4) developing a method to abstract the compliant mechanism into a form of links and joints by using the principle of connectivity on topology;(5) developing a method of shape optimization of planar path-generating compliant mechanisms, by representing the profile of the abstracted compliant mechanism as simple curves such as straight lines and arcs, establishing the models of the size optimization of the parameters of these curves, so that the compliant mechanism has a machinable shape;(6) At last, proving the feasibleness and effectiveness of the design method by making simulation design and validating it in FEA software.

主要工作包括：(1)分析了柔顺机构拓扑优化和形状优化的研究现状，分析了目前柔顺机构的研究重点、主要成果和尚未解决的问题；(2)分析了基于SIMP的柔顺机构概念设计方法及其相关工具和模型；(3)针对柔顺机构轮廓提取的特殊要求，提出了密度等值线法的改进方案，对密度函数插值点密度值进行优化，提出优化模型和选择优化算法；(4)根据轨迹输出平面全柔顺机构自身的形状特点，提出了轨迹输出平面全柔顺机构的抽象方法，即应用拓扑学上的连通性原理将柔顺机构抽象成杆件和结点形式，并对相应的数学原理进行了证明；(5)提出了平面全柔顺机构的形状还原和尺寸优化方法，对抽象的柔顺机构进行还原，将其轮廓还原成简单曲线的连接，从而建立尺寸优化模型，对机构进行尺寸优化设计，在得到可加工的机构轮廓的同时又能对关键部位进行特别处理；(6)进行了柔顺机构的数值仿真设计，并将所得设计结果导入商用有限元软件中进行仿真实验，证明了设计方法的可行性和有效性。

From this, we can analyze the distribution rule of interaction force between pile and rock and give mathematical regress equation of curve.

5绘制结点应力与抗滑桩埋深关系曲线，分析曲线得出桩土间作用力分布规律，并求出曲线的数学回归方程。

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。

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。