关键词： context   context-aware   mobile computing   mobility   evaluation   empirical  

摘要： There is a clear need for evaluation methods that are specifically suited to mobile device evaluation, largely due to the vast differences between traditional desktop computing and mobile computing. One difference of particular interest that needs to be accounted for is that mobile computing devices are frequently used while the user is in motion, in contrast to desktop computing. This study aims to validate the appropriateness of two evaluation methods that vary in representativeness of mobility, one that uses a treadmill to simulate motion and another that uses a controlled walking scenario. The results lead to preliminary guidelines based on study objectives for researchers wishing to use more appropriate evaluation methodologies for empirical, data-driven mobile computing studies. The guidelines indicate that using a treadmill for mobile evaluation can yield representative performance measures, whereas a controlled walking scenario is more likely to adequately simulate the actual user experience. (c) 2005 Published by Elsevier Ltd.

关键词： MOBILE computing   ELECTRONIC apparatus & appliances   LAPTOP computers   INFORMATION technology   TECHNOLOGICAL innovations   ELECTRONICS  

摘要： The article reports that conventional wisdom about mobile computing says that end users are willing to carry only one device. This belief has led vendors to race to create the perfect single product. The problem with converged devices, though, is that they require compromises on functionality, and in fact the single-device notion is more myth than reality. Any device that requires its own case, like a projector or large laptop computer, means end users must carry a significantly larger load, in terms of both bulk and weight. Because users must make a concerted effort to carry such a device, they will do so only when they need the dedicated functionality. Pocketable devices are carried independently, on the person. Reducing functionality in the interest of making a device smaller is foolish if the device isn't made pocketable. Likewise, increasing functionality while losing the ability to be carried ubiquitously can be wrong as well. IT departments need to be careful when selecting devices for end users, and form and function need to go hand in hand. At the same time, users should not try to sacrifice functionality for the sake of device size.

关键词： chemical shift calculation   GIAO method   vinyl bromide   cyclopropane  

摘要： We present a comparison between the theoretical and experimental H-1 and C-13 chemical shifts of molecules 1-5. In order to compute the chemical shifts, it was necessary to calculate the geometric parameters for the cited alcohols considering in any case the level of theory used in the chemical shift treatment. Thus, RHF ab initio and DFT with at least 6-3 1 G(d) basis sets were used. The geometry parameters of alcohol 1 compare well with X-ray data. The theoretical chemical shifts were obtained using the GIAO, method in association with RHF ab initio and DFT levels of theory with at least 6-31G(d) basis sets. Associations with RHF ab initio geometry and DFT levels of theory for the GIAO calculations were also tested. This data set indicates that there are problems of geometric character in the calculation of the brominated vinylic system. On the other hand, the calculations for the nortricyclenic cycloropane ring are in good agreement with experimental findings. (c) 2005 Elsevier B.V. All rights reserved.

关键词： 嵌入式移动数据库   Windows   CE   移动计算   OLEDB  

摘要： 随着掌上电脑和智能手机等移动设备的广泛普及 ,移动计算渐成热点。

关键词： 迅驰   移动计算技术   英特尔公司   笔记本电脑   电池使用时间   发布   办公   接人网   平台   支持  

摘要： 英特尔公司不久前发布了其用于笔记本电脑的最新英特尔迅驰^TM移动计算技术。这一全新移动平台配备了丰富的娱乐与办公特性，包括一流的图形显示能力、更出色的响应能力和更强大的安全选件支持等，同时还有诸如集成无线接人网访问和耐久电池使用时间等重要性能。

关键词： 迅驰移动计算技术   奔腾M处理器   英特尔公司   主频   芯片组   赛扬   笔记本电脑   GMS   平台   BG  

摘要： 英特尔公司发布了其用于笔记本电脑的最新英特尔迅驰移动计算技术。英特尔迅驰移动计算技术包括移动式英特尔915PM或915GM Express芯片组；英特尔PRO／无线2195ABG或2200BG网卡；以及主频为1．60GHz～2．13GHz的英特尔奔腾M处理器。此外，英特尔迅驰移动计算技术还采用了移动式英特尔915GMS Express芯片组、主频为1．50GHz的低压英特尔奔腾M处理器758，以及主频为1．20GHz的超低压英特尔奔腾M处理器7530英特尔还推出了主频为1．

关键词： 移动计算设备   笔记本电脑   掌上电脑   移动电话   正式策略   环境保护   访问控制   加密技术  

摘要： 使用移动计算设备(如笔记本电脑、掌上电脑、移动电话)时．尤其应该注意保证业务信息不受损坏。

关键词： 移动IP   移动接入网   移动节点   移动性   便携设备   IP网络   通信   移动计算   安全问题   安全性问题  

摘要： 由于移动便携设备的日益普及,这就要求Internet有支持移动计算的能力;移动IP支 持基于IP网络的节点的移动性,极有可能成为未来通信环境的关键构成部分,但是移动节点移动接入 网络的同时,必然带来一系列的完全问题。本文主要就移动IP的安全性问题进行了分析,并讨论了相 应的解决方法以及存在的不足。

关键词： 运输业   零售业   终端   科技公司   物流业   企业用户   增加   移动计算   处理器   微软  

摘要： 日前．美国讯宝科技公司(Symbol ***)宣布针对全球零售业、运输业和物流业用户推出最新MC3000手持移动计算终端。新推出的MC3000手持移动计算终端更轻15、更坚固．具有空前的灵活性和更强的环境适应性．是企业用户提高数据采集效率、增加灵活性的理想工具。为了发挥其最佳性能．MC3000手持移动计算终端采用英特尔公司的最新X级处理器和界面直观的微软WindowsCENET平台。

关键词： 移动计算   实时事务   事务相关图   数据收集  

摘要： 在移动环境下,为了满足实时事务在移动主机断接后数据的可用性,在事务启动前,数据必须收集到移动主机的缓存中。根据实时事务的相关性,给出了实时事务的相关图。介绍了基于时间阈值、空间阈值、数据的有效期阈值的收集算法,有效保证数据的可用性和实时事务的定时限制。