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31.
Pseudo-random testing techniques for mixed-signal circuits offer several advantages compared to explicit time-domain and frequency-domain test methods, especially in a BIST structure. To fully exploit these advantages a suitable choice of the pseudo-random input parameters should be done and an investigation on the accuracy of the circuit response samples needed to reduce the risk of misclassification should be carried out. Here these issues have been addressed for a testing scheme based on the estimation of the impulse response of the device under test (DUT) by means of input-output cross-correlation. Moreover, new acceptance criteria for the DUT are suggested which solve some ambiguity problems arising if the classification of the DUT as good or bad is based on a few samples of the cross-correlation function. Examples of application of the proposed techniques to real cases are also shown in order to assess the impact of the measurement system inaccuracies on the reliability of the test. 相似文献
32.
The development of future mobile networks will be driven, in large part, by content and web based services. In this paper,
we examine several performance, scalability and architectural challenges faced by future mobile web applications and how advanced
mobile content delivery techniques can address these challenges. We review existing content delivery using a taxonomy that
consists of three categories: network scaling, end system acceleration, and content and protocol optimization. While wireline
content delivery focuses on network and server scalability, mobile content delivery will likely benefit most from optimizing
radio link usage. We also present our ongoing work in this area, which extends the functionality of edge caching to the terminal,
uses user interest correlation information to maintain low terminal power consumption and adds a new dimension to radio resource
management.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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34.
两个基于身份的数字签名方案的安全性改进 总被引:2,自引:0,他引:2
分析了文献[1]提出的两个基于用户身份的数字签名方案,发现其一般签名方案存在安全性缺陷,在此基础上建立了多重签名方案,但此方案也是不安全的。本文给出了改进的签名和多重签名方案。 相似文献
35.
Stateful session handoff for mobile WWW 总被引:1,自引:0,他引:1
This paper proposes a web session handoff system that can hand over not only stateless but also stateful sessions between homogenous and heterogeneous user devices to enable uninterrupted and seamless web access. The proposed system adopts a proxy-based approach and an optional client-assisted scheme in order to track and hand over session information. In the proposed system, a session is registered at a User Agent Proxy (UAP) and then tracked by the UAP so that the session can be handed over from one device via the UAP to another device. In addition to session information tracked by a UAP, the UAP can hand over more comprehensive session information by using the client-assisted scheme. Compared with client-based approaches, our design has several advantages, such as less modification to user devices, practicability, and fault tolerance. We have implemented a UAP on a PC and client programs for both PC and PDA. The implementation can successfully hand over between PC and PDA a stateful session for online shopping applications. 相似文献
36.
论文提出了基于椭圆曲线上EIGamal加密体制的数字签名方案,并出于安全性的考虑进行了一点改动。另外,应用了Tate配对对签名进行验证。 相似文献
37.
一个通用代理计费系统开发框架的设计与实现 总被引:4,自引:4,他引:0
用户在不同的网络环境中选择不同的代理软件实现上网和用户管理,这些代理软件既有共性又各具特色,为减少开发不同代理计费软件的工作量,提高开发效率,加快开发周期,提出利用软件重用的思想,将代理软件的差异集中到少数几个类的实现上,设计并实现一个通用代理计费系统开发框架,基于此框架利用相对简单的步骤开发了基于SQUID的代理计费系统,验证了框架的实用性和可行性,达到了设计目标。 相似文献
38.
TAN Zuo-wen 《通讯和计算机》2007,4(5):40-46
Signcryption is a public key or asymmetric cryptographic method that provides simultaneously both message confidentiality and integrity at a lower computational and communication cost. This paper presents a (t, n) threshold proxy signcryption scheme in which no less than t proxy agents in the proxy group can produce the signcryption cryptogram. combines the functionality of threshold proxy signing and encryption. The proposed scheme combines the functionality of both threshold proxy signing and encryption, and provides fair protection for the sender and the proxy agents. This scheme is secure against attack of public key substitution. It also satisfies security properties such as confidentiality and authenticity. 相似文献
39.
40.
坦克红外特征控制技术评述 总被引:2,自引:1,他引:1
坦克红外特征控制对于提高坦克的战场生存能力具有重要意义。控制的主要方法有遮障、表面处理、外形技术、主动冷却、总体设计等。坦克红外特征的控制必须与其他波段,特别是射频波段的特性控制兼容。遮障和低发射率涂料是现役坦克红外特征控制的主要措施。而对未来的主战坦克,设计应是减少其系统特性的重要途径。 相似文献