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In this thesis,based on the DFT+NEGF first-principles method,we construct a lead-molecule-lead sandwich system with single benzene-based molecule to investigate the relationship between the structure and properties of the molecular devices and the factors that influence properties of the molecular devices.Our computational investigations on these molecular devices are primarily concentrated on the effect of contact geometry between molecules and electrodes,the effect of side groups,the effect of different torsion angle between two phenyl rings and the effect of external electric field.This thesis consists of five chapters:In Chapter one,we mainly introduce the research background and development of the molecular electronics,including the experimental fabrication of molecular electronic components and theoretical simulation methods.Afterwards we discuss the questions that need to be solved in this area.Finally,the main contents of this thesis are listed.In Chapter two,we introduce the theoretical methods used in this thesis, including the main first-principles calculation methods,i.e.,the Density-Functionmethod and nonequilibrium Green\'s function.

本论文拟采用密度泛函理论和非平衡格林函数相结合的第一性原理计算方法，选取苯基小分子作为研究对象，构建了金属电极/有机小分子/金属电极三明治结构体系，系统地研究了苯基分子器件结构的改变与分子电输运性质之间的关系以及影响分子器件电输运性质的相关因素，其中重点研究了分子与电极间可能的接触结构改变、官能团、分子间的扭转角以及外电场对苯基分子电输运性质的影响，本论文主要包括以下五个章节的内容：第一章为综述部分，主要介绍了分子电子学产生的背景、分子器件的研究意义、当前研究分子器件的实验和主要理论方法，以及目前在研究分子器件中存在的一些问题，最后给出了本论文的主要研究内容和技术路线。

Based on the projectile-borne mechanism angular motion simulation device, a new testing method for the projectile-borne mechanism motion test is provided, which is based on the ARM embedded system.

研究弹道环境下弹载机构的运动规律是引信等弹载机构设计、研制、故障分析和性能评价的重要依据和基础'了。

The description methods of natural scenery was studied based on fractal, that is, recursive method, L-system method, IFS and IFS description method was put forward based on sine or cosine. This method overcomes angularity and consistency of recursive method, L-system method and IFS, and the variety of fractal sculpting consequence can be added and the basis for the later research and the application was provided.

对基于分形的描述自然景物方法，即递归洪、L-系统法、IFS法进行了分析研究，在此基础上，提出基于正余弦的IFS描述法，该方法克服了递归法、L-系统法、IFS法等描述方法的生硬性和一律性，增加了分形造型结果的多样性，为以后的深入研究和应用提供了依据。

Based on the laminate theory, a laminate weakened by damage is treated as an anisotropic thin plate. Using the complex potential method in the plane theory of elasticity of an anisotropic body, the series solution of finite anisotropic thin plate containing an elliptical inclusion is proposed with the help of Faber series. A hybrid element with an elliptical inclusion for anisotropic materials is obtained by using the hybrid variable principle, and the element efficiency is verified by numerical examples. The state of the damage is modeled by an elliptical soft inclusion, and using the point stress criterion based on characteristic curve and Yamada-Sun etc. criteria, the prediction of the strength of a composite laminate with damage is set up. The effects of various parameters on the stress distribution and the residual strength of a composite laminate weakened by damage are detailedly studied.

首先基于经典层板理论，将复合材料层板的弹性问题化归为均匀各向异性板来求解；采用各向异性体平面弹性理论中的复势方法，以Faber级数为工具，给出了有限大含椭圆核各向异性板弹性问题的级数解形式；利用杂交变分原理，成功导出含椭圆核各向异性板杂交应力有限元，并用算例验证了该单元的可行性和有效性；采用含刚度折减椭圆形弹性核的冲击损伤模型，引入基于特征曲线和Yamada-Sun破坏准则的点应力判据，建立了含损伤复合材料层板剩余强度的分析方法；通过数值计算详细讨论了各种几何参数对损伤层板应力分布、剩余强度的影响，得到了一系列对工程应用具有实用价值的结论。

To study the regular human gaits,the test system based on string displacement sensor and human joint angle measurement instrument are used to measure the motion trajectory of anklebone and the joint angles of lower limb under walking in different road conditions,and the measurement data is analyzed and treated based on human rigidbody model and with data fusion method.Then the gaittrajectories and standphases are gotten under the condition of upstairs,normal walking and downstairs.The result shows that the longest standphase is in upstairs condition,the middle is normal walking and the shortest is downstairs.

为研究人体的步态运动规律，采用基于拉线传感器检测系统和人体关节角度测量装置，对人在不同路况下行走时踝关节运动轨迹和下肢关节角度进行了测量，根据人体下肢刚体模型和数据融合方法对测量结果进行了分析和处理，得到了人在上楼梯、平地行走和下楼梯时的步态轨迹和3种路况下的支撑相；上楼梯时的支撑相最大，平地行走次之，下楼梯最小。

For protecting the anonymousness of the sender as well as to provide the authentication,an ID-based ring signature scheme suited for distributed and collaborative design system is proposed based on GDH group.

分布式协同设计[1-2]是网络化制造的核心技术，指分布在不同地域的产品设计人员，通过互联网对制造资源异地交互，相互协同地设计和开发产品。

Based on the three dimensional surface data of the face and skull, methods of geometric analysis on them are presented through these parameters with their numerical calculating methods under the landmarks of the anthropologist and anthropometrist are proposed,which is the foundation of the statistical model that will be used in the field; 4Geometric analysis methods that based on the approximation coefficients of spherical harmonic functions are proposed.

以三维面皮和颅骨数据为基础，分别给出了基于公安法医学标志点和人体测量学标志点的几何分析主要途径和方法，确定了几何分析的主要参量，并给出了相关的计算方法，为建立颅面统计模型奠定基础； 4基于球面调和函数的颅面形态学的几何分析方法。

And based on the deformation method, an error model of the virtual human anthropometry was proposed, and a new method of the skin deformation was proposed, based on the anthropometry error model constraints.

利用Barr以及NFFD算法实现虚拟人的四肢皮肤变形，提出了人体测量学数据的误差分析模型，并在此基础上提出了一种满足误差精度要求的人体皮肤变形方法。

This paper first introduces the theory and method of vehicle automated driving based on magnetic markers,analyzes the results of vehicle automated driving based on the apery control and points out the shortcoming of it.

介绍了基于磁道钉导航的车辆自动驾驶的原理和实现方法，分析用此方法建立仿人控制模型来实际控制车辆自动驾驶的结果，指出仿人控制模型的不足之处。

The results show that: the fillers of SiO_2 based investment consist of SiO_2,Al_2O_3 and MgO,and the binder is NH_4H_2PO_4;for SiO_2 based investment,the bulk density and the compression strength decrease,the apparent porosity and the thermal expansion increase,when the specimens are heated to 900 ℃;the fil.

结果表明：氧化硅系包埋料的骨料是氧化硅、氧化铝、氧化镁，结合剂为磷酸二氢铵，其900℃煅烧后显气孔率增加，体积密度下降，耐压强度降低，热膨胀增大；氧化铝系包埋料的骨料是氧化铝和氧化镁，结合剂为磷酸二氢铵，其900℃烧后显气孔率增加，体积密度下降，热膨胀变化不大；氧化镁系包埋料的骨料是氧化镁和氧化铝，结合剂是铝酸钙水泥，其900℃烧后耐压强度明显降低，热膨胀明显增大。

Don not attempt to do something which you can not to do.

不要企图做那些办不到的事情。

The expression of CTGF and TNF-αweredetected by immunochemistry and the number of Clara Cells was calculated.

光镜下观察肺组织的病理变化，采用免疫组化染色观察肺组织中结缔组织生长因子和肿瘤坏死因子-α的表达和Clara细胞的数量。