三角形网格细分法及其在曲面造型中的应用

网格细分造型技术因其计算规则简单、可以表示任意拓扑特性和几何特征的曲面等性质,受到造型技术领域中众多学者的关注,而三角形网格细分的许多算法已经成功应用于该领域。本文介绍了网格细分的相关理论,重点介绍了三角形网格细分法以及在曲面造型中的应用,为曲面造型提供了一种新的方法。     

Au与ZnO极性表面相互作用的第一原理计算

采用第一原理研究了Au在ZnO两个极性表面（0001）-Zn和（0001）-O的吸附,分析了单层Au吸附在ZnO极性表面上的态密度和吸附构型.计算结果表明：ZnO极性表面上单层Au吸附层能提高Zn原子在（0001）-Zn和（0001）-O面上的吸附能分别0.41 eV/原子和0.42 eV/原子;同时Au吸附层又比Zn吸附层更加活跃,总能计算可以看出Au处于顶端的构型比Au扩散构型更加稳定,使得Au恒处于顶端,很好的解释了Au在ZnO纳米结构生长过程中充当表面活性剂的角色.理论计算与实验中发现Au颗粒总是在生长出的纳米结构的末端这一现象吻合很好.     

Similarity-based denoising of point-sampled surface

A non-local denoising (NLD) algorithm for point-sampled surfaces (PSSs) is presented based on similarities, including geometry intensity and features of sample points. By using the trilateral filtering operator, the differential signal of each sample point is determined and called "geometry intensity". Based on covariance analysis, a regular grid of geometry intensity of a sample point is constructed, and the geometry-intensity similarity of two points is measured according to their grids. Based on mean shift clustering, the PSSs are clustered in terms of the local geometry-features similarity. The smoothed geometry intensity, i.e., offset distance, of the sample point is estimated according to the two similarities. Using the resulting intensity, the noise component from PSSs is finally removed by adjusting the position of each sample point along its own normal direction. Experimental results demonstrate that the algorithm is robust and can produce a more accurate denoising result while having better feature preservation.     

油红O显现渗透性客体上潜在手印研究

分别采用甲醇、乙醇、丙酮、医用酒精作为有机溶剂配制染液,验证油红O显现法的实际显现效果.综合试剂取材的方便性、操作步骤的简便性、试剂使用的环保性以及手印的实际显现效果,结果表明,油红O医用酒精染液实验结果较好.该研究对于油红O显现法在基层司法鉴定工作中的应用推广具有一定的现实意义.     

CPn中的齐次曲面

从齐性曲面的等距群出发,讨论CPⁿ中的齐性曲面,得到了CPⁿ中等距群为2维的齐性曲面的分类,并且用李群与活动标价相结合的方法给出了CP²中齐性曲面的分类定理的证明。     

尺寸链原理在定位误差分析计算中的应用

提出了定位误差尺寸链中封闭环的确定方法与定位误差的求解过程,澄清了定位误差尺寸链计算中易混淆的几个问题,简化并规范了定位误差的计算,同时从尺寸链原理角度对定位误差进行理论分析,叙述了定位误差的影响因素。     

关于de Sitter 空间中的紧致类空超曲面(英文)

本文得到ｄｅ Ｓｉｔｔｅｒ 空间中紧致类空超曲面的２ 个性质,推广了Ｓ．Ｍｏｎｔｉｅｌ 的结论．     

Muscle activity and spine load during anterior chain whole body linkage exercises: the body saw,hanging leg raise and walkout from a push-up

This study examined anterior chain whole body linkage exercises, namely the body saw, hanging leg raise and walkout from a push-up. Investigation of these exercises focused on which particular muscles were challenged and the magnitude of the resulting spine load. Fourteen males performed the exercises while muscle activity, external force and 3D body segment motion were recorded. A sophisticated and anatomically detailed 3D model used muscle activity and body segment kinematics to estimate muscle force, and thus sensitivity to each individual's choice of motor control for each task. Gradations of muscle activity and spine load characteristics were observed across tasks. On average, the hanging straight leg raise created approximately 3000 N of spine compression while the body saw created less than 2500 N. The hanging straight leg raise created the highest challenge to the abdominal wall (>130% MVC in rectus abdominis, 88% MVC in external oblique). The body saw resulted in almost 140% MVC activation of the serratus anterior. All other exercises produced substantial abdominal challenge, although the body saw did so in the most spine conserving way. These findings, along with consideration of an individual's injury history, training goals and current fitness level, should assist in exercise choice and programme design.     

多重扭曲时空中类空超曲面的唯一性定理及其应用

得到了多重扭曲时空中常平均曲率类空超曲面的一个唯一性定理．作为应用,证明了反deSitter时空中位于两同心Veronese超曲面之间的完备常平均曲率类空超曲面一定是Veronese超曲面。由该唯一性定理还可直接推得有关文献中的相应结果．     

圆弧方程曲面铣削零件的编程设计

以典型的圆弧方程曲面铣削零件为研究对象,设计了零件加工工艺,分析了宏程序的编程方法,通过调用宏程序和子程序,编制出了数控加工程序。