用SEA法分析地对空雷达对抗系统的时效性

时效性分析是地对空雷达对抗系统效能评估的重要内容,本文利用SEA方法建立了一个时效性分析模型。首先建立一个干扰站的时效性分析模型,然后在此基础上进一步建立整个地对空雷达对抗系统的时效性分析模型,最后通过算例验证了模型的正确性和实用性。     

家电产品常用板材的选用

本文首先介绍国内和日本、德国、俄罗斯等国冷轧薄钢板及镀锌薄钢板的牌号、标记识别及生产地及与我国家标准薄钢板牌号的相互之间的关系，并比较具体地介绍冷轧板的实效性、镀锌薄钢板的锌层特性等诸多方面的状况。从而帮助我们在设计、制造家电产品中，比较正确地选择合适的板材。     

The incremental benefits of changes in the timeliness of information

The managers of all purposeful organizations rely on historical information as an aid to decision making. Information enables managers to formulate expectations about the future. Less timely information is generally inferior because the manager's expectations will contain greater error; and the operating results obtained may therefore be less satisfactory. The timeliness of information often can be improved by incurring incremental systems costs. However, the degree to which such improvements will produce benefits is uncertain. This research uses modeling to explore the relationship between information timeliness and the benefits derived by implementing optimal decisions based upon the information. The most significant finding is that the shape of this relationship is dependent upon the scope of the action set available to the decision maker. If a continuous range of options is available (such as a pricing decision), then the relationship is linear. If only a few discrete options are present (as in linear programming) the relationship is more complex but describable. The decision maker is therefore found to be in a position to offer guidance to the systems designer which will facilitate enhancement of the benefit/cost characteristics of the organization's information resource.     

QoS-oriented design of embedded systems with specification PEARL

Only recently have methodical tools adequate to design real-time systems been formally introduced in design methodologies. Naturally, they were present from the beginning, but due to the large diversity of embedded systems’ areas of deployment, specially dedicated formalisms have been developed and used. High-level language programming and integration of modeling formalisms into design methods eased the development of more complex real-time applications. With the emerging object-oriented programming languages and design methods, their integration into larger information systems has become more transparent. It was the UML methodology, however, which eventually merged also the design methods and concepts of real-time systems into a consistent whole. It took a large consortium and a long process to persuade industry of the benefits the new integral methodology can offer. On the other hand, there are some trade-offs, and there are some features not completely covered, yet. Here, a different, more straightforward approach to program and design (embedded) real-time systems is presented. Since it emerged from the real-time community, it includes most features relevant there. Independent of the UML profile for schedulability, performance and time specification, a profile was devised for use in PEARL-oriented UML design. The strengths of the mentioned language and design methods for QoS-oriented design of (embedded) real-time systems are emphasised throughout this article.     

Determinants of consumers’ attitudes toward mobile advertising: The mediating roles of intrinsic and extrinsic motivations

Mobile advertising is booming, due to the popularity of mobile devices. Drawing on motivation theory, this study examines the factors that influence consumers’ attitudes toward mobile advertising. The authors identify timeliness, localization, and personalization of the advertisement message as antecedents of extrinsic motivation, as well as consumer innovativeness and perceived enjoyment as antecedents of intrinsic motivation. Using structural equation modeling, the study analyzes the conceptual model with a sample of 218 mobile phone users. Both intrinsic and extrinsic motivations mediate the effects of the advertising message’s characteristics on mobile phone users’ attitudes toward mobile advertising.     

浅谈分布式虚拟现实及其实时性研究

分布式虚拟现实系统简称DVR,是虚拟现实系统的一种类型,它是基于网络的虚拟环境。在这个环境中,位于不同物理环境位置的多个用户或多个虚拟环境通过网络相连接,或者多个用户同时参加一个虚拟现实环境,通过计算机与其他用户进行交互,并共享信息。在分布式虚拟现实系统中,多个q用户可通过网络对同一虚拟世界进行观察和操作,以达到协同工作的目的。简单地说是指一个支持多人实时通过网络进行交互的软件系统,每个用户在一个虚拟现实环境中,通过计算机与其它用户进行交互,并共享信息。     

Automatic information timeliness assessment of diabetes web sites by evidence based medicine

Studies on health domain have shown that health websites provide imperfect information and give recommendations which are not up to date with the recent literature even when their last modified dates are quite recent. In this paper, we propose a framework which assesses the timeliness of the content of health websites automatically by evidence based medicine. Our aim is to assess the accordance of website contents with the current literature and information timeliness disregarding the update time stated on the websites.     

PageRank算法研究

简要分析了PageRank算法的思想及其不足,对国内外研究工作者的改进算法进行了分类,比较了它们的优缺点。对未来的研究方向进行了展望,给出了若干值得研究的问题。     

建筑?更像装置 2010年上海世博会国家馆

为了回应"城市,让生活更美好"的主题,2010年上海世博会各国家馆采取了"命题作文"式的建筑诠释,甚至是过度诠释。文章以装置艺术的视野,试图从"建筑"之外解读和剖析2010年上海世博会各国家馆。     

Adaptive timeliness of consensus in presence of crash and timing faults

The Δ$\mathrm{\Delta }$-timed uniform consensus is a stronger variant of the traditional consensus and it satisfies the following additional property: every correct process terminates its execution within a constant time Δ$\mathrm{\Delta }$ (Δ$\mathrm{\Delta }$-timeliness), and no two processes decide differently (uniformity). In this paper, we consider the Δ$\mathrm{\Delta }$-timed uniform consensus problem in presence of _fc$f_{\mathrm{c}}$ crash processes and _ft$f_{\mathrm{t}}$ timing-faulty processes, and propose a Δ$\mathrm{\Delta }$-timed uniform consensus algorithm. The proposed algorithm is adaptive in the following sense: it solves the Δ$\mathrm{\Delta }$-timed uniform consensus when at least _ft+1$f_{\mathrm{t}}+1$ correct processes exist in the system. If the system has less than _ft+1$f_{\mathrm{t}}+1$ correct processes, the algorithm cannot solve the Δ$\mathrm{\Delta }$-timed uniform consensus. However, as long as _ft+1$f_{\mathrm{t}}+1$ processes are non-crashed, the algorithm solves (non-timed) uniform consensus. We also investigate the maximum number of faulty processes that can be tolerated. We show that any Δ$\mathrm{\Delta }$-timed uniform consensus algorithm tolerating up to _ft$f_{\mathrm{t}}$ timing-faulty processes requires that the system has at least _ft+1$f_{\mathrm{t}}+1$ correct processes. This impossibility result implies that the proposed algorithm attains the maximum resilience about the number of faulty processes. We also show that any Δ$\mathrm{\Delta }$-timed uniform consensus algorithm tolerating up to _ft$f_{\mathrm{t}}$ timing-faulty processes cannot solve the (non-timed) uniform consensus when the system has less than _ft+1$f_{\mathrm{t}}+1$ non-crashed processes. This impossibility result implies that our algorithm attains the maximum adaptiveness.