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61.
The high expectations and demand for users to access the Internet from anywhere at anytime has made user mobility an important part of the design and development of the next generation mobile communications and computing. Traditionally user mobility has been divided into two areas: Terminal Mobility and Personal Mobility. In recent years terminal mobility has focused on the movement of the terminal and developed extensions to IP protocols such as Mobile IP. In contrast, personal mobility has only received limited attention, and is somewhat lagging behind. This research has either focussed on personal mobility in communications or personalisation of operating environments. As a result, to date no framework for providing true personal mobility has emerged. In this paper, we introduce a new personal mobility framework called IPMoA (Integrated Personal Mobility Architecture), which integrates both aspects of personal mobility to provide a complete personal mobility solution, and illustrate the viability of this approach through a proof-of-concept implementation.  相似文献   
62.
模块化软件开发的标准化内涵和优势分析   总被引:3,自引:0,他引:3  
简述了模块化理论的基本观点,着重从消费者和生产者两个角度分析了实施软件模块化开发的优势,指出了模块化开发的标准化内涵,揭示了软件开发方法上的模块化趋势。  相似文献   
63.
It is shown that In/sub 1-x/Ga/sub x/As/In/sub 0.52/Al/sub 0.48/As MQW structures with the wells under tensile strain obtained by the appropriate selection of the Ga mole fraction and well size can achieve polarization-insensitive optical switching and modulation for a wide range of wavelengths between 1.0 and 1.6 mu m. For example, a change in refractive index of -0.5% at about 1.55 mu m will facilitate an intersectional angle of more than 10 degrees in a total internal reflection switch which can be readily fabricated. Hence, this material system is promising for long-wavelength polarization-insensitive semiconductor optoelectronic devices.<>  相似文献   
64.
激光光束质量诊断技术的进展   总被引:1,自引:0,他引:1  
巩马理  金锋 《激光杂志》1995,16(4):145-147,153
本文介绍了激光光束质量诊断技术近年来的进展,以及国际标准化组织推荐的聚集光束测量法,指出了该技术的发展方向。  相似文献   
65.
阐述了新型线圈式磁弹性扭矩传感器的原理,推导出其输出表达式,进而说明了线圈式磁弹性扭矩传感器具有输出平稳、响应快的特点。  相似文献   
66.
The feasibility of the anodic protection of titanium evaporators in Al2(SO4)3 solution was studied by the measurement of polarization curves, weight loss, solubility of passive film and AC impedance. The protection parameters and efficiency were determined. In addition, the practical technology of anodic protection was studied by screening reference electrodes and auxiliary cathodes. Throwing power was also measured. Four rows of tube-type evaporators of titanium have been anodically protected in situ. Field tests lasting more than one year show satisfactory results.  相似文献   
67.
钱新明  吕虹辉 《黄金》1995,16(4):35-39
本文对硫酸和氰化钠分步解吸载金树脂上的贱金属离子,以及用硫脲硫酸溶液解吸载金树脂上的金、银络离子的解吸过程进行了研究,并通过现场采集的数据绘制了解吸曲线。  相似文献   
68.
69.
In recent years, three‐dimensionally (3D) braided composites have attracted a great deal of attention because of their high‐impact damage tolerance and fatigue life, superior fracture toughness, and so forth, and have been used in aeronautics, military, and transportation. These advantages make them strong candidates for osteosynthesis devices. In this study, 3D braided carbon fiber–epoxy (C3D/EP) composites were produced via a simple vacuum impregnation technique. The load‐deflection curve, mechanical properties, and influence of fiber volume fraction, braiding angle, and axial reinforcing fibers were examined to determine their suitability for internal fixation devices. It is found that the C3D/EP composites have excellent toughness and do not show brittleness when fractured because of their relatively high void content. The flexural, shear, and impact strengths of the C3D/EP composites are excellent. It was shown that a C3D/EP composite with a stiffness similar to load‐bearing bones can be made while maintaining enough strength. It is concluded that a relatively higher void content and braiding angle is more suitable for the C3D/EP composites from the viewpoint of requirements of fracture fixation materials. The moisture absorption behavior and changes in mechanical properties caused by moisture uptake were evaluated. Results show that absorbed moisture slightly decreases mechanical properties of the C3D/EP composites. Contrary to the unreinforced epoxy, the moisture absorption behavior of the C3D/EP composites cannot be described with Fick's law of diffusion, probably because of the presence of voids and/or 3D fiber structure. The exact mechanisms should be proposed in further investigations. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1031–1039, 2002  相似文献   
70.
由于悬空侧壁部分的变形状态是圆锥形零件成形的关键,而径向拉应力是实现悬空部分成形的必要条件,同时也是该部分冲压成形成败的关键为此,经力学分析得出了侧壁部分径向拉应力的解析式和造成圆锥形零件破裂的最大径向拉应力的计算式。同时分析了圆锥形零件的成形载荷。  相似文献   
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