Effects of the Fabrication Processes of NC-Si： H Films on Their Mechanical Properties

Studies of nanoindentation were performed on nc-Si：H films to evaluate the effects of the fabrication processes on their mechanical properties. It is observed that with the decrease of the SiH4 contents, the grain size of the films increases gradually, and as does the crystalline volume fraction. The smaller the grains become, the more homogeneous the films, and the more even the hardness as well as the modulus will be. The hardness and the modulus will increase with the substrate＇s temperature rising. The hardness and the modulus of the nc-Si：H films on the Si substrate prove to be higher than those on the glass substrate given the same technology parameters. How- ever, the films on the glass substrate appear to be more homogeneous.     

制造企业正在跨入知识时代

制造企业正在从工业时代跨入知识时代，制（手）造正在转向智造。传统的生产组织必须转变为创造知识的组织，特别是面向全球的学习组织。高水平的智力资源是制造企业的最宝贵的资产。     

片梭织机骨架的制造与装配

本文概述了片梭织机骨架的制造、装配中的难点及所采取的工艺措施。     

倾斜功能材料的制造技术及应用

本文简要介绍了热应力缓和型倾斜功能材料的制造技术及应用。     

超级巨无霸A380正式启动

２ ０００年１２月１９日在世界航空史册上 将具有重要意义。这天，在图卢兹举行的空客公司监事会上，空客公司的股东一欧洲航空防卫航天公司（ＥＡＤＳ）和英宇航公司（ＢＡｅ Ｓｙｓｔｅｍｓ）决定正式批准发起Ａ３８０项目。该机型就是此前被广泛宣传，受到航空制造界和航空运输业人士重点关注，称为是面向２１世纪机型的Ａ３ＸＸ． 在人类航空史上，最近一次宣布生产世界上最大型飞机是 １９６６年 ３月波音公司董事会批准Ｂ７４７的启动。具有鲜明的鹅头特征的Ｂ７４７—４００目前仍然是世界上最大型的飞机，通过垄断这部分最大型飞机…     

应用于DSMC方法的二维Voronoi网格技术

研究了Voronoi网格技术并将其应用于直接模拟蒙特卡洛DSMC(Direct Simulation Monte Carlo)计算.基于Dirichlet镶嵌与Voronoi图理论,Voronoi网格利用特征点表征网格单元,具有建立粒子与网格单元之间映射关系的独特算法,适合于DSMC方法的统计特点.在剔除过于靠近边界的特征点以及必要情况下边界细化的基础上,通过区分由边界节点表征的非完整Voronoi网格单元以及由计算区域内镶嵌点表征的完整Voronoi网格单元,解决了Voronoi网格的二维边界匹配问题.Voronoi网格技术支持自适应DSMC计算.映射效率对比表明,Voronoi网格的DSMC计算效率高于三角形网格,低于多级直角网格.通过MEMS微喷管流动数值模拟,验证了Voronoi网格技术在DSMC方法中的有效性.      

HISTORICAL PROCEDURES AND G-DSG METHOD BASED MANUFACTURING PLANNING

Oriented to CAD/CAM seamless integration, this paper presents an idea for synthetically considering the qualitative history model, which represents the whole course of modeling, and the quantitative geometry model, which contains the extended Brep model, CSG and feature pedigree. History model building captures in background the dynamic interactive definition of engineering requirement and then explicitly conveys the original intention to successive application layers, which isc onductive to the decision support of manufacturing planning in not only automatic geometry re-constructing but also machining set-up. G-DSG theory as an earlier achievement is applied to generate the topology-independent generalized mid-model as an input to manufacturing planning, which istherefore simplified and its accuracy is simultaneously improved. Manufacturing planning lays emphasis on optimizing the mapping in both geometry and function from part itself to detail machining scheme. Comparatively, process planning pays more attention to the mapping to those items like tool, fixture, etc. Theoretically, such an idea is also beneficial to realizing the parametric NC machining trajectory generation and maintaining its dynamic consistency with the update of the design model.     

阵风减缓直接升力控制方案的仿真研究

阵内减缓技术可有效地抑制飞机飞行过程中受到阵风和湍充影响所产生的附加过载。研究阵风载荷减缓的基本原理及各种控制方案,结合我国的实际情况,提出了以副翼作为直接升力操纵面的阵风减缓控制方案,建立了直接升力控制的阵风减缓系统的数学模型,并就阵风减缓系统进行了计算机辅助设计与仿真,验证了方案的可行性。     

CIMS环境下的模具CAD／CAPP／CAM技术

在CIMS环境下的模具CAD／CAPP／CAM技术将零件设计,模具设计,模具制造有机地集成起来,实现信息的集成与共享,缩短产品的开发和生产准备时间,提高产品的质量。