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991.
We are investigating the role of high performance computing for support of a comprehensive pathology image atlas. The primary computing component is a database access mechanism providing retrieval by content based image matching (CBIR) along with traditional term based queries. An organization based on information theoretic and Bayesian principles using decision trees and signature files is being developed. The essential role of HPC is the discovery, selection, and optimization of medically useful image feature sets via genetic algorithm and simulated annealing methods. This paper outlines the problem area along with aspects of the underlying theoretical basis and distinguishing computing characteristics. Efficiency of key portions of the computations can be greatly improved by using parallelism within the computer word length using bit counting instructions to implement voting and multimedia style instruction sets for low level image processing. 相似文献
992.
Generally speaking, parameter selection in all cryptographic algorithms and protocols is a mixture of art and science and exerts various subtle influences on a system, which is related to application requirements, security policies, the compromise between security and the overheads of computation, storage and communications, the balance between security and availability, and to the efficiency of software /hardware implementation, etc. Usually, simplistic, insecure or impractical textbook crypto… 相似文献
993.
994.
针对机载无线移动自组网中无可信中心以及公钥证书维护开销过大问题,提出了一种无密钥托管的基于身份的签名认证方案.在随机预言机模型下证明了该方案的签名不可伪造性,并且在签名认证过程中避免了复杂的双线性对运算、指数运算和求逆运算,具有很高的执行效率. 相似文献
995.
为了研究群签名方案的前向安全性和后向安全性保证技术,基于哈希链实现了一种具备前向安全和后向安全的群签名方案,在密钥更新阶段采用门限方法与其他成员共享其每个时间周期内的子秘密,在签名生成阶段成员利用公开信息和哈希函数单向性验证其他参与者份额的真实性,即使在验证失败的情况下也可由多个参与者利用门限方案合作完成群签名,提升了系统的安全性和稳定性.分析表明,该方案比现有同类群签名方案具有更好的安全性和更高的效率. 相似文献
996.
该文针对现有的无证书环签名大多都使用昂贵的双线性对的问题,利用前向环序列提出一个无双线性对的无证书环签名方案,并对该方案的性能进行了详细的分析.与已有的无证书环签名相比,它完全避免了双线性对运算,计算成本降低,实用性更强. 相似文献
997.
A novel architecture of Proxy‐LMA mobility management scheme for software‐based smart factory networking
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Mobile users expect a network service, in which seamless handoff occurs while moving on a next generation wireless network. In addition, in smart factories (SFs), communication is required between factory floor and manufacturing zone, as well as connectivity towards office IT, or remote production facilities that are connected via wide area network or internet. For this purpose, interworking between heterogeneous networks is important, but there has been little research on global mobility support. Therefore, this paper proposes Proxy‐LMA technology, a mobile IP‐based global internetworking system, to improve global mobility and interoperability in the SFs network environment. The purpose of the proposed Proxy‐LMA system is to support global mobility by using mobility management protocols such as PMIPv6 and MIPv6 in heterogeneous network environment. As a result of the performance evaluation, Proxy‐LMA system is more efficient than other methods in terms of signaling cost and response delay in heterogeneous network environment. Software‐based networking in SFs enables them to easily adapt the communication network to changing requirements. Similar to cloud‐based systems, such SFs could be seen as production clusters that could be rented and configured as needed. The SF network uses software‐defined networking combined with network functions virtualization, to achieve the required flexibility. Despite the fact that the technology is nowadays not yet ready for deployment in today's manufacturing networks, a novel network architecture for SFs based on software‐defined networking and network virtualization is here proposed, to support smart services, especially for Industrie 4.0. 相似文献
998.
999.
群签名使得群中任何一个成员均可以代表该群进行签名,而不会暴露签名者的身份.当争议发生时,签名者的身份可以通过群管理员公开.成员删除一直是群签名方案设计中难以解决的一个问题,何业锋等人最近在《软件学报》上提出了一个利用ELGamal加密和知识签名提出的一个动态群签名方案.指出该方案中被删除的群成员仍然可以作出签名,因而他们的方案是不安全的. 相似文献
1000.
Dheeraj Bansal David J. Evans Barrie Jones 《International Journal of Machine Tools and Manufacture》2006,46(10):1068-1078
An algorithm, to estimate the machine system parameters from the motion current signature, based upon non-linear time series techniques for use in the real-time predictive maintenance system is presented in this paper. Earlier work has introduced the use of a neural-network approach to learn non-linear mapping functions for condition monitoring systems. However, the performance of the neural-network largely depends upon the quality of the training data, and that of the quality and type of the pre-processing of the input data. A reverse algorithm called BJEST (Bansal–Jones Estimation), for estimating the machine input parameters using the motion current signature, has been designed and proven to be successful in estimating the macro-dynamics of the motion current signature. This motivated the enhancement of the predictive analysis to incorporate non-linear characteristic of the motion current signature. The results show considerable improvement in the estimation of the parameters using the enhanced BJEST algorithm due to estimation consistency, hence, improving the real-time predictive maintenance system. 相似文献