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71.
基于身份的电子印章设计与实现 总被引:1,自引:0,他引:1
随着办公自动化的发展,电子文档逐渐取代了传统的纸制文档。电子印章可以有效保障企业办公自动化中电子文档的安全性。在分析现有电子印章的签名方案的基础上,提出基于身份的电子印章的设计方法,给出基于身份电子印章系统的构架和相应的签名算法。最后指出该方法安全性以及特点。 相似文献
72.
针对传统电子商务平台存在的问题,提出了一个以移动Agent为中介服务的电子商务交易平台,阐述了该平台各组成部分的功能.实验采用价格优先和数量优先的购买策略,分析了该平台中移动Agent的性能,实验仿真结果表明移动Agent的引入提高了平台处理客户信息的速度,缩短了达成交易的时间并降低了网络的通信量. 相似文献
73.
用GIS制作的电子地图成本非常高。本文介绍了一种通过OpenGL技术搭建电子地图的方法。该方法将地图信息分别放置在不同的层中,通过调整视点的位置对地图进行放大、缩小、显示特定区域。 相似文献
74.
基于程序升温法保留时间预测的气-质联用系统构建虚拟实验室 总被引:1,自引:1,他引:0
在气-质联用技术的理论研究及实验的基础上,采用Flash 8.0和ActionScript 2.0编程技术构建开放式网络气-质联用系统虚拟实验室。以若干有机物为考察对象,根据程序升温色谱法(PTGC)中保留值与温度及流速的关系,构建了不同色谱分析条件下保留参数的预测模型,同时利用Flash组件技术,构建与虚拟实验配套的气-质联用系统虚拟工作站。 相似文献
75.
76.
电子编务在现代化科技期刊编辑出版中的应用 总被引:1,自引:0,他引:1
通过对电子编务在现代化科技期刊编辑出版中的应用探讨,使我们进一步认识电子编务不仅可以提升编辑在日常编辑工作的效率,使得编辑出版流程环节简化、规范,强化稿件管理,提高出版效率,而且对编辑部在竞争激烈的科技期刊出版环境下生存和发展能力的提高起着重要的作用。 相似文献
77.
C. Quitmann P. Almeras Jian Ma R. J. Kelley H. Berger G. Margaritondo M. Onellion 《Journal of Superconductivity》1995,8(5):635-636
Doping Bi2Sr2Ca1Cu2O8+y with Co causes a superconductor-insulator transition. We study correlations between changes in the electrical resistivity ab(T) and the electronic bandstructure using identical single crystalline samples. For undoped samples the resistivity is linear in temperature and has a vanishing residual resistivity. In angle resolved photoemission these samples show dispersing band-like states. Co-doping decreases Tc and causes and increase in the residual resistivity. Above a threshold Co-concentration the resistivity is metallic (dab/dT>0) at room temperature, turns insulating below a characteristic temperature Tmin and becomes superconducting at even lower temperature. These changes in the resistivity correlate with the disappearance of the dispersing band-like states in angle resolved photoemission. We show that Anderson localization caused by the impurity potential of the doped Co-atoms provides a consistent explanation of all experimental features. The coexistance of insulating (dab/dT <0) normal state behavior and superconductivity indicates that the superconducting ground state is formed out of spatially almost localized carriers. 相似文献
78.
The electronic momentum distribution n(k) of the two dimensional Hubbard model is studied for different values of the coupling U/t, electronic density n , and temperature, using quantum Monte Carlo techniques. A detailed analysis of the data on 8 × 8 clusters shows that features consistent with hole pockets at momenta k=(±/2,±/2,) appear as the system is doped away from half-filling. Our results are consistent with recent experimental data for the cuprates discussed by Aebi et al. (Phys. Rev. Lett.72, 2757 (1994)). In the range of couplings studied, the depth of the pockets is maximum at n approximately 0.9, and it increases with decreasing temperature. The apparent absence of hole pockets in previous numerical studies of this model is explained. 相似文献
79.
Patients with chronic illnesses, such as diabetes, need daily care and follow-up beyond occasional visits to healthcare providers. Research has shown that overcoming a multifaceted illness, such as diabetes, requires patients to be engaged in the monitoring and management of their own health. Health information technology (HIT) has been shown to empower chronically-ill patients to take charge of their healthcare, and alleviate their daily frustrations while they strive to lead a normal life. In this paper, we surveyed 31 patients with diabetes to identify the major frustrations they experience daily, examine the role of HIT in their current treatment, and identify gaps in their current care and education that, if addressed, could improve their quality of life. Themes identified in our survey results include a lack of interaction with healthcare providers, difficulties in scheduling appointments, a lack of timely communication with healthcare providers, and challenges in managing the complex care of diabetes. The contributions of this paper include a detailed set of recommendations on how HIT can be utilized to help chronically-ill patients live a better life despite their illnesses, with a particular emphasis on diabetes care and management. 相似文献
80.
II-VI and III-V tetrahedral semiconductors have significant potential for novel optoelectronic applications. In the present work, some of the optical and electronic properties of these groups of semiconductors have been studied using a recently proposed empirical relationship for refractive index from energy gap. The calculated values of these properties are also compared with those calculated from some well known relationships. From an analysis of the calculated electronic polarisability of these tetrahedral binary semiconductors from different formulations, we have proposed an empirical relation for its calculation. The predicted values of electronic polarisability of these semiconductors agree fairly well with the known values over a wide range of energy gap. The proposed empirical relation has also been used to calculate the electronic polarisability of some ternary compounds. 相似文献