形状

FT-IRDSC tests were taken to analyze the structure,and the terms-mechanical properties,shape recovery behaviors and tensile properties were discussed to study the extender influence on SMPU.The results show that SMPU extended by ethanediol and FA has good micro-phase separation structure and soft...

结果发现，扩链剂对SMPU有一定影响，用FA、ED扩链的SMPU具有较好的微相分离，而DE扩链的具有较好的软段结晶性能；FA、HD的SMPU具有较低的形状回复温度和较快的形状回复速率，HD、DE扩链的则具有较好形状固定性能，FA、DE扩链的SMPU循环使用性能较好；同时FA、HD的SMPU具有较高的弹性模量与力学强度。

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。

The reverse martensitic transformation of TiNi shape memory alloy fibers embedded in a pure aluminum matrix was studied in this paper.

为了改进形状记忆合金的性能和延长形状记忆合金的寿命，跟踪和研究疲劳前后形状记忆合金的显微结构变化是十分重要的。

As revealed by the voltage topographic maps and the tomographic mapping, the source location of the distinct N1 is in the occipitotemporal areas.

并且，与单纯形状知觉任务相比，图形形状和空间位置知觉任务表现枕颞区N2波幅的显著减弱，P3潜伏期的王著缩短，额区的P2波幅的显著减弱；(3)脑电地形图与高分辨率断层成象显示，两种任务的特征波N1成分均来源于双侧的枕颞皮层，表明两种任务均涉及到与物体形状识别相关的视皮层腹侧通路，而差别波dN2成分来源于左侧枕颞区，暗示特征加工的差异主要发生在左侧枕颞区。

The basic principle is that basic geometry shape of openings in the photo is revised; the image can't be distortion by use of projection reconstruction; the corrected image is exerted by open operation and close operation of gray-image; the shape of openings is gained lastly. The perimeter borderline of openings shape is extracted. The quantity of overbreak as well as underbreak is gained by comparing to extracted perimeter and designed perimeter. The same method is applied to other opening sections. Evaluation of overbreak as well as underbreak in the openings can be easily solved in the way of quantitative.

其基本原理是：对野外摄取的洞室的基本剖面形状进行几何校正，然后应用图像学中的投影重建方法使图像不失真，对修正后的图像实行灰度图像的开操作和闭操作运算，得到洞室的基本形状，然后用图像学中的边界提取技术提取洞室的周边界，与洞室的设计形状对比分析，得到洞室在该断面上的超欠挖方量，然后对其它断面采用同样的技术就可评价某一段或整个洞室的超欠挖数量，从定量的角度解决了工程中的超欠挖评价问题。

It was found that percentage recovery decreases with the increasing of prestrain and increases with the increasing of annealing temperature and there is a higher percentage recovery when up to 600℃ of annealing temperature.

实验表明，合金的形状回复率随预变形量的增加而减小；形状回复率随回复温度的升高而增大，且在600℃左右达到最大值；热-机械训练可以明显提高合金的形状记忆效应。

The effect of training, prestrain amount and recovery annealing temperature on the shape memory effect, the absolute shape recovery ratio , and the superelasticity of Fe14Mn6Si9Cr5Ni alloy is studied.

研究了训练、预应变量和退火温度对Fe14Mn6Si9Cr5Ni合金的形状记忆效应、绝对形状回复率和超弹性的影响，测定了合金的蠕变和应力松驰特性，讨论了降温ε马氏体对形状记忆效应的间接贡献。

"Now we can study how molecular structure affects the shape, which affects the mechanical properties, and both of which affect mobility," said study author Subra Suresh of MIT.

&现在我们可以研究分子结构是如何影响细胞形状的，细胞形状又是影响力学特性的。然而，形状和力学特性都会影响物质的流动性，&该研究的发起人、美国麻省理工学院的苏伯拉·苏雷什说。

The model is proved by the numerical simulation of three engineering cases. The SMA superelastic damper of tension-pressure type is introduced. The design and the working principle of the damper are outlined.

采用本文的形状记忆合金一维超弹性本构关系模型对工程算例进行了数值模拟，试验和数值模拟结果表明，本文的形状记忆合金超弹性一维本构关系模型，能够比较真实地模拟NiTi形状记忆合金在温度和应力作用下的受力性能，并且形式简单，计算方便，可满足工程应用要求。

Here we report the crystal structure of the parainfluenza virus 5 F protein in its prefusion conformation, stabilized by the addition of a carboxy-terminal trimerization domain.

首先，它们以一个亚稳态的形状出现，这个形状能储存进入细胞所需的能量；然后，该蛋白形状所发生的不可逆转的变化促成膜的融合。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。