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91.
安全有效的路由算法是P2P网络的关键技术之一.针对目前大多数P2P路由算法没有考虑安全性问题,并且采用随机选择下一跳节点的方法会降低路由效率,给出了一种新的P2P安全路由算法.该算法采用信任度与路径可靠性指导下一跳节点的选择,以建立安全有效的路由路径,并且引入加密、多路径传输等方法以抑制篡改、窃听等典型攻击.模拟实验结果表明,该路由算法的路由效率要优于Gnutella,安全性能好.  相似文献   
92.
In this paper, the design of reliability sampling plans for the Pareto lifetime model under progressive Type-II right censoring is considered. Sampling plans are derived using the decision theoretic approach with a suitable loss or cost function that consists of sampling cost, rejection cost, and acceptance cost. The decision rule is based on the estimated reliability function. Plans are constructed within the Bayesian context using the natural conjugate prior. Simulations for evaluating the Bayes risk are carried out and the optimal sampling plans are reported for various sample sizes, observed number of failures and removal probabilities.  相似文献   
93.
由模糊可靠性的基本概念和原理,建立了一套计算混联系统(Ⅱ)的模糊可靠性公式  相似文献   
94.
This paper reviews recent developments in the stochastic comparison of order statistics. The results discussed are basically: (l) Stochastic comparisons of linear combinations of order statistics from distributions F and G where G?1 F is convex or starshaped. (2) Stochastic comparisons of individual order statistics and of vectors of order statistics from underlying heterogeneous distributions by the use of majorization and Schur function theory. (3) Stochastic comparison of random processes. Applications to reliability problems are presented illustrating the use and value of the theoretical results described  相似文献   
95.
The post World War II Industrial Revolution has driven production away from the old 'economies of scale' to the new 'economies of scope'. Apparently Japanese led, the associated roots of present good practice on material flow can be traced back in the USA to Jay Forrester and in the UK to Jack Burbidge. Specifically, in the supply chain scenario, Forrester exposed the importance of system structure in relating and integrating information flow with material flow. Similarly Burbidge led the way in exploiting cycle time reduction, synchronization of orders throughout the chain, simplified product structures, and streamlined component flows. This paper unites their contributions to material flow engineering and shows how present day system design methodologies incorporate their ideas on best practice. These principles are particularly relevant to the product delivery process (PDP) which governs material flow in supply chains.  相似文献   
96.
In this paper solutions of renewal-type integral equations are studied. It is proved that a recursively spades;efined approximation to the solution has some nice convergence properties. Some simple bounds and other results on the renewal function and the renewal spades;,ensity are obtained.  相似文献   
97.
As assumed hypothetical consensus category corresponding to a case being classified provides a basis for assessment of reliability of judges. Equivalent judges are characterised by the joint probability distribution of the judge assignment and the consensus category. Estimates of the conditional probabilities of judge assignment given consensus category and of consensus category given judge assignments are indices of reliability. All parameters can be estimated if data include classifications of a number of cases by 3 or more judges. Restrictive assumptions are imposed to obtain models for data from classifications by two judges. Maximum likelihood estimation is discussed and illustrated by example for the 3 or more judges case.  相似文献   
98.
中小企业有效融资是世界性难题,全球范围内"麦克米伦缺口"依然十分突出。在中国,"麦克米伦缺口"有着不同于其他国家和地区的特征和成因,因此也产生了针对这些特殊性的中国式治理。虽然目前的各种治理方法还略微粗糙,却有效地缓解了困扰已久的中小企业融资窘境。随着治理"麦克米伦缺口"各种探索的持续深入,中国金融界在不久的将来或许就能全面破解这一世界性的难题。  相似文献   
99.
本文从提高数控系统的可靠性出发,阐述了数控系统抗干扰设计的必要性。具体讨论了数控系统中一些实用而有效的抗干扰技术。  相似文献   
100.
This paper examines the relationship between environmental regulatory influence and product innovation in a multi-industry sample of manufacturing organizations. Our theory argues that the influence of environmental regulation on the level of product innovation in a manufacturing organization is at least partially contingent on the organization's internal characteristics—in particular, its structural flexibility and production process flexibility. Hypotheses are derived from our theory and tested, and the results are consistent with the conclusion that structural flexibility and production process flexibility moderate the environmental regulatory influence–product innovation relationship. Whether environmental regulation inhibits or promotes product innovation seems to depend at least in part on certain internal features of an organization. We discuss implications of our results for future organization studies research on environmental regulation, and for research on other types of external constraints on organizational performance.  相似文献   
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