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1.
PKI/CA技术综述   总被引:6,自引:0,他引:6  
公开密钥基础设施(PKI)是解决网络安全的技术.典型PKI应用系统包括安全Web、注册机构(RA)、认证机构(CA)、目录(LDAP)和数据库等服务器.RA验证客户证书申请后提交CA.CA检查信息完整和数字签名正确后把证书存放到证书库和目录服务器,并将签发证书序列号通知客户和RA.客户即可使用该号通过目录服务器下载证书.1993年以来,美、加、欧洲、韩、日等国已相继展开PKI研究.我国2001年将PKI列入十五863计划,并着手解决PKI标准化、CA互联互通等关键技术问题。  相似文献   
2.
基于EAI的多层分布式应用与实现   总被引:5,自引:0,他引:5  
针对目前大型企业各类应用迅速增加但应用之间缺乏有效通信的问题,采用企业应 用集成(EAI)技术,提出了4层分布式应用体系结构,实现流程自动化和松耦合的应用集成.文中首先从EAI技术和常见解决方案出发,详细阐述了表示层、企业门户、EAI总线层和数据源层的功能及软件结构,并结合电信业务运营支撑系统的实际需求,给出了J2EE平台下的应用实例开发.利用组件和容器的技术构建企业门户,通过工作流和企业Java组件(EJB)技术实现EAI总线,借助资源适配器完成应用之间的互连互通.该系统现已投入实际运行,取得了良好的应用效果.  相似文献   
3.
Ting-Lin   《Technology in Society》2006,28(4):533-552
For the past decade, the Taiwanese government has applied the policy of “North heavy, South light” to put more emphasis on development in northern Taiwan instead of the south. This has resulted in uneven development between the northern and southern regions, especially when introducing, developing, and supporting high technology and resource allocation in education. Industry clusters have become the centerpiece of economic development policy in many parts of the world. In this study, it is assumed that there are two categories of less-advantaged regions in Taiwan: (1) older industrialized regions dominated by labor-intensive/capital-intensive industries, and (2) industrial regions that have merged with potential high-technology small firms but still lack infrastructure. This study discusses the following points: (a) How do industrial clusters work in action? (b) What barriers do less-advantaged industrial clusters face? (c) What action strategies promote less-advantaged industrial clusters?  相似文献   
4.
本文研究了加法复合布尔函数和乘法复合布尔函数,在平衡性、k次项系数、K次扩散准则(PC)、相关免疫 性(CI)、Walsh谱、代数次数、小项分布等方面得到了一批新结果。  相似文献   
5.
太阳电池板结构应力-应变状态分析   总被引:2,自引:0,他引:2  
多层胶接是太阳电池板的结构特点,由于不同材料的弹性模量、热膨胀系数和泊松比不同,在温度场 作用下会产生热应力应变,在多次热交变过程中热应力.应变累积最后导致结构层间剥离,因此研究温度场作用 下太阳电池板结构应力应变状态具有非常重要的实际意义。本文推导了模拟太阳电池板结构应力-应变状态的一 维模型,该模型同样适用于分析多层胶接结构应力应变状态。  相似文献   
6.
随着招投标过程信息化的快速发展,越来越多的招标、评标、中标信息统一集中在相应交易中心平台网站上进行公示,使采用大数据手段分析建设工程信息成为了可能。采用Web Scraper插件爬取网页内容简便、高效、准确。大数据的介入能很大程度遏制非法围标、串标行为,保证公共资源交易过程的公平、公正,有效打击权力寻租。同时大数据分析以定量、可视化的成果展示了建设工程的市场行为趋势,为政府的宏观调控提供更精确的数据性指导性意见。  相似文献   
7.
The paper suggests a new methodology for secure cyber–physical systems design. The proposed methodology consists of two main cycles. The main goal of the first cycle is in design of the system model, while the second one is about development of the system prototype. The key idea of the methodology is in providing of the most rational solutions that are improving the security of cyber–physical systems. Such solutions are called alternatives and built according to functional requirements and non-functional limitations to the system. Each cycle of the methodology consists of the verification process and seven stages that are associated with the used cyber–physical system model. The objective of the verification process is in checking of constructed models and prototypes in terms of their correctness and compatibility. The model represents cyber–physical systems as sets of building blocks with network between them, takes elements internal structure into account and allows direct and reverse transformations. The novelty of the suggested methodology is in the combination of design, development and verification techniques within a single approach. To provide an example of the design methodology application, in this paper it is used to improve the semi-natural model of the railway infrastructure.  相似文献   
8.
首先分析了虚拟化给传统信息安全带来的挑战,然后分别从边界防护、病毒防护、补丁管理以及虚拟化基础设施保护四个方面,阐述了在虚拟化环境下如何进行安全防护。  相似文献   
9.
Thermal sprayed aluminum and zinc provide long-term (> 20 years to first maintenance) corrosion control coatings. However, this application is usually more expensive than painting or galvanizing if thermal spraying (metallizing) is not integrated into the design and fabrication phases of new construction and repair projects. Aluminum and zinc metallized coatings are tough enough to withstand fabrication, transportation, and assembly operations. The improved capabilities and productivity of metallizing equipment for aluminum and zinc spraying are a major factor in their current cost competitiveness. The net result is that the cost difference between metallizing, paint, and galvanizing is getting closer every day. Even though the initial application cost of metallizing may be higher, the life cycle cost (LCC) and average equivalent annual costs (AEAC) are lower than paint coating systems. Metallizing LCCs, when properly engineered into the construction schedule, are equal to or less than paint coating LCCs. This article summarizes some metallizing considerations for installing improved corrosion control coating systems in new construction and in maintenance and repair of infrastructure. Editor’s Note: The following constants have been used to convert between English and Metric dimensions: 1ft2-0.0929 m2; 1lb/ft2-4.89 kg/m2; 1 mil=0.025mm. Presented at the 5th National Thermal Spray Conference (NTSC-93), Infrastructure Maintenance and Repair Session, 10 June 1993, Anaheim, CA.  相似文献   
10.
《Information & Management》2014,51(8):1031-1042
Customer relationship management (CRM) has become one of the most influential technologies in the world, and companies are increasingly implementing it to create value. However, despite significant investment in CRM technology infrastructure, empirical research offers inconsistent support for its positive impact on performance. This study develops and tests a research model analyzing the process through which CRM technology infrastructure translates into organizational performance, drawing on the resource-based view (RBV) and the knowledge-based view (KBV) of the firm. Based on an international sample of 125 hotels, the results suggest that organizational commitment and knowledge management fully mediate this process.  相似文献   
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