快速逆向工程系统及其关键技术

本文论述了快速逆向工程的系统框架及其关键技术，系统集成是逆向工程的核心，关键技术是其支撑。简要阐述了逆向工程的基本内涵及其工作过程；构建了快速逆向工程系统结构框架；重点分析了快速逆向工程的关键技术-快速仿形测量、曲面重构与快速原型技术；最后对快速逆向工程中存在的问题进行了讨论。     

硅胶表面光引发制备氨基比林分子印迹聚合物的研究

以光引发剂二乙基二硫代氨基甲酸钠对硅胶表面进行修饰,以氨基比林为模板分子、甲基丙烯酸为单体、乙二醇二甲基丙烯酸酯为交联剂,在修饰后的硅胶表面接枝共聚制备分子印迹聚合物。利用红外光谱、电镜对聚合物进行了表征,用紫外分光光度法考察了分子印迹聚合物对氨基比林的吸附特性。结果表明,印迹聚合物对模板分子具有较高的吸附能力和选择识别能力。     

叹息过后的思索——浅析影片《一声叹息》的表层结构与深层结构

深层结构潜隐在表层结构中，并转化生成众多的表层结构。影片《一声叹息》的故事情节是从表层结构走向深层结构的过程，并在深层结构中表现出根植于一定文化中的社会心理内涵和更凝重，更具普遍性的审美意义。     

几何画板轨迹功能在三维曲面绘制中的应用

探讨了几何画板的绘图功能在空间曲面绘制中的应用,给出通过建立基础网格利用“轨迹”功能绘制曲面网状图和建立三维坐标系利用“追踪”功能绘制曲面的方法。     

Surface settlement caused by twin-parallel shield tunnelling in sandy cobble strata

City metro tunnels are usually constructed as twin-parallel tunnels and their adjacent construction may lead to surface deformation, affecting the surface environment and the safety of the tunnels. Due to its strong dispersion, sandy cobble strata can be easily disturbed by shield tunneling. Based on the project of the Chengdu Metro Line 1, field and model tests were carried out to study the surface settlement caused by shield tunneling in sandy cobble strata by measuring surface settlement curves, ground loss ratios and construction influence zones. The discrete element method (DEM) was used to study the factors affecting the formation of ground arches in sandy cobble strata at the microscopic level. Results show that the shape of the surface settlement curve in sandy cobble strata is different from that in soft soil. The buried depth and clear spacing of the two tunnels had a significant impact on the formation of ground arches.     

Study on the thermal decomposition kinetics of nano-sized calcium carbonate

This study of the thermal decomposition kinetics of various average diameter nano-particles of calcium carbonate by means of TG-DTA (thermogravimetry and differential thermal analysis) showed that the thermal decomposition kinetic mechanisms of the same crystal type of calcium carbonate samples do not vary with decreasing of their average diameters; their pseudo-active energyE _a; and that the top-temperature of decompositionT _p decreases gently in the scope of micron-sized diameter, but decreases sharply when the average diameter decreases from micron region to nanometer region. The extraordinary properties of nano-particles were explored by comparing the varying regularity of the mechanisms and kinetic parameters of the solid-phase reactions as well as their structural characterization with the variation of average diameters of particles. These show that the aggregation, surface effect as well as internal aberrance and stress of the nano-particles are the main reason causing bothE _a andT _p to decline sharply with the decrease of the average diameter of nano-particles. Project supported by Guizhou Province Natural Science Foundation of China     

A comparative study of student attitude,learning and teaching practices in Pakistan and Britain

Good teaching is open to change and it involves constantly trying to find out what the effects of instruction are on learning, and modifying that instruction in the light of the evidence. Similarly, the ultimate outcome of instructional practice is effective student learning. Therefore, in this perspective, adequately meeting the varying needs of students is a major challenge for the modern education system in every country. As the title indicates, this paper attempts to explore students’ attitudes to studying and learning in order to help encourage greater engagement with quality learning. The study is based on primary data with regard to postgraduate education and learning in respective British and Pakistani education institutions—i.e. Moray House School of Education (Edinburgh University) and the Institute of Education and Research (University of the Punjab, Lahore). In the context of the collaboration of these two institutions, the paper focuses on the ways and means to enhance the system‐wide capacity for research‐based practice.     

Modeling of contact surface morphology and dust particles by using finite element method

The effect of dust particles on electric contacts and a hazardous size range of hard dust particles using a rigid model were discussed before. As further research, elastic-plastic model of finite element analysis was established in this work, which is closer to real condition. In this work, the behavior of large size and small size particles, and the influence of particles hardness were investigated. The calculating result of small-size particles presents a general hazardous size coefficient for different contact surface morphology; for large-size particles, it presents a hazardous size coefficient for complicated composition of the dust. And the effect of the dust shape is also discussed.     

Influence of surface treatments on fatigue life of a two-stroke free piston linear engine component using random loading

INTRODUCTION Fatigue durability has long been important issues in the design of a two-stroke free piston linear engine structure (Torres and Voorwald, 2002; Rahman et al., 2005a; 2005b). Durability assessment is traditionally done in the later part of the product development stage when prototypes are available, and heavily re- lied on in confirming ground durability tests. This process is very time consuming and often results in over-design with weight penalties, which is the major obsta…     

薄带钢连铸技术的发展

主要介绍了国内外薄带钢连铸技术的发展和双辊式薄带连铸的现状，包括连铸机设备结构、工艺参数、浇注钢种以及产品规格、质量等，并分析了影响薄带连铸的几个关键技术。