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We consider the problem of sending a message from a sender to a receiver through an unreliable network by specifying in a protocol what each vertex is supposed to do if it receives the message from one of its neighbors. A protocol for routing a message in such a graph is finite if it never floods with an infinite number of copies of the message. The expected reliability of a given protocol is the probability that a message sent from reaches when the edges of the network fail independently with probability .We discuss, for given networks, the properties of finite protocols with maximum expected reliability in the case when is close to 0 or 1, and we describe networks for which no one protocol is optimal for all values of . In general, finding an optimal protocol for a given network and fixed probability is challenging and many open problems remain. 相似文献
3.
为了克服传统的结构可靠指标求解方法存在的模型描述和计算缺陷,引入改进混合蛙跳算法用于求解可靠指标。针对标准蛙跳算法求解组合优化问题时后期收敛速度慢、容易陷入局部最优的缺点,新算法引入蚁群算法的信息素调整策略,对蛙跳算法后期局部搜索进行改进,扩大算法后期搜索范围,使蛙跳算法跳出局部最优。最后,将改进后的算法应用到结构可靠指标的求解过程,算例验证了改进算法的有效性。 相似文献
4.
??The reliability of gas fire-extinguishing system is difficult to calculate because of the small sample size, so this paper uses Bayesian method to calculate reliability of the gaseous fire-extinguishing system. The method process includes conversion of multi-source prior information, information fusion, information check, weight calculation and reliability calculation of unit and system. The method properly solves the problem of reliability calculation by combining the field sample information with multi-source prior information. 相似文献
5.
应力为SGBVE分布强度为指数分布下结构可靠度的估计 总被引:3,自引:0,他引:3
考虑了应力服从SGBVE分布,强度服从指数分布的应力—强度模型,分别在应力参数未知和部分强度参数未知的情形下给出了该模型可靠度的估计,并讨论了其性质. 相似文献
6.
High throughput N-modular redundancy for error correction design of memristive stateful logic 下载免费PDF全文
Memristive stateful logic is one of the most promising candidates to implement an in-memory computing system that computes within the storage unit. It can eliminate the costs for the data movement in the traditional von Neumann system. However, the instability in the memristors is inevitable due to the limitation of the current fabrication technology, which incurs a great challenge for the reliability of the memristive stateful logic. In this paper, the implication of device instability on the reliability of the logic event is simulated. The mathematical relationship between logic reliability and redundancy has been deduced. By combining the mathematical relationship with the vector-matrix multiplication in a memristive crossbar array, the logic error correction scheme with high throughput has been proposed. Moreover, a universal design paradigm has been put forward for complex logic. And the circuit schematic and the flow of the scheme have been raised. Finally, a 1-bit full adder (FA) based on the NOR logic and NOT logic is simulated and the mathematical evaluation is performed. It demonstrates the scheme can improve the reliability of the logic significantly. And compared with other four error corrections, the scheme which can be suitable for all kinds of R-R logics and V-R logics has the best universality and throughput. Compared with the other two approaches which also need additional complementary metal-oxide semiconductor (CMOS) circuits, it needs fewer transistors and cycles for the error correction. 相似文献
7.
汪建华 《数学的实践与认识》2017,(13):1-8
教育评估的可靠性决定了评估结果的可信性,影响着教育评估的声誉和发展.结合高校领军人才评审探讨了数学可靠性模型在教育评估中的应用,通过建立数学可靠性模型,计算评审系统的可靠性,并结合可靠性计算结果分析了影响评审系统可靠性的因素. 相似文献
8.
Single nucleotide polymorphisms (SNPs) are the most common genetic polymorphisms and play a major role in many inherited diseases. Methylenetetrahydrofolate dehydrogenase 1 (MTHFD1) is one of the enzymes involved in folate metabolism. In the present study, the functional and structural consequences of nsSNPs of human MTHFD1 gene was analyzed using various computational tools like SIFT, PolyPhen2, PANTHER, PROVEAN, SNAP2, nsSNPAnalyzer, PhD-SNP, SNPs&GO, I-Mutant, MuPro, ConSurf, InterPro, NCBI Conserved Domain Search tool, ModPred, SPARKS-X, RAMPAGE, FT Site and PyMol. Out of 327 nsSNPs form human MTHFD1 gene, total 45 SNPs were predicted as functionally most significant SNPs, among which 17 were highly conserved and functional, 17 were highly conserved and structural residues. Among 45 most significant SNPs, 15 were predicted to be involved in post translational modifications. The p.Gly165Arg may interfere in homodimer interface formation. The p.Asn439Lys and p.Asp445Asn may interfere in binding interactions of MTHFD1 protein with cesium cation and potassium. The two SNPs (p.Asp562Gly and p.Gly637Cys) might interfere in interactions of MTHFD1 with ligand. 相似文献
9.
以四个敏感器的冗余系统为例,对采用冗余敏感器的惯导系统的可靠性进行了分析,对四个敏感器构成的捷联惯导系统的可靠性进行了仿真实验,验证了冗余敏感器可以提高系统可靠性结论的正确性。中给出非正交敏感器测量值向惯导系统正交坐标系转化的方法和转换矩阵。最后对冗余敏感器的配置方式进行了分析。通过仿真实验,得到敏感器最佳配置的条件。 相似文献
10.
基于可靠度的结构优化的序列近似规划算法 总被引:3,自引:0,他引:3
基于可靠度的优化的最直观解法是把可靠度和优化的各自算法搭配一起形成嵌套两层次迭代。为改善其收敛性提高计算效率,人们提出了功能测度法、半无限规划法、单层次算法等多种改进方法。本文对传统结构优化界的经典序列近似规划法改造并扩展应用于求解基于可靠度的结构优化问题,构造该问题的序列近似规划模型和求解过程;其核心思想是在每个近似规划子问题中采用近似可靠度指标对设计变量的线性近似,在优化迭代过程中同步更新设计变量和随机空间中的近似验算点坐标,以达到可靠度分析和优化迭代同步收敛的目标。为了算法的实施,还推导出近似可靠度指标的半解析灵敏度计算公式,编制了程序,最终实现与通用软件的连接。论文用算例证实算法的有效性。 相似文献