175,098 research outputs found

    A termination protocol for simple network partitioning in distributed database systems

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    Resilient commit protocols for multisite simple network partitioning are studied in this paper. The necessity of termination protocols to make commit protocols resilient in multisite simple network partitioning is presented. A termination protocol that makes the three-phase commit protocol resilient is designed. This protocol is valid even for transient network partitioning. The method can be generalized to design termination protocols for other commit protocols in multisite simple network partitioning.published_or_final_versio

    Tri-State Boolean Satisfiability with Commit: An Efficient Partial Solution Using Hyperlogic

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    We present two implementation enhancements for the Boolean satisfiability problem and one visualization technique. The first is an expansion to a tri-nary logic system with a commit phase. The three states are (1) true, (2) false, and (3) don\u27t care. We abstracted the operations of AND and OR to this hyperlogic system in a novel way. The commit phase works on one variable at a time and transitions values from temporary to permanent whenever possible. We viewed tri-state logic as a hyperspace above the binary (Boolean) logic. The second improvement is algorithmic. We modified the semantics of the classic 3 Conjunctive Normal Form Problem in order to develop a polynomial time algorithm for a simplified normal form - avoiding the need to examine all combinatoric limitations. In particular, we abandoned 3 CNF and used an unstructured left to right associativity. We do not claim that this new semantic is comprehensive. We do claim that it is simpler. Lastly, we introduced a node analogy to help us understand the algorithm itself

    A double-edged sword: Benefits and pitfalls of heterogeneous punishment in evolutionary inspection games

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    As a simple model for criminal behavior, the traditional two-strategy inspection game yields counterintuitive results that fail to describe empirical data. The latter shows that crime is often recurrent, and that crime rates do not respond linearly to mitigation attempts. A more apt model entails ordinary people who neither commit nor sanction crime as the third strategy besides the criminals and punishers. Since ordinary people free-ride on the sanctioning efforts of punishers, they may introduce cyclic dominance that enables the coexistence of all three competing strategies. In this setup ordinary individuals become the biggest impediment to crime abatement. We therefore also consider heterogeneous punisher strategies, which seek to reduce their investment into fighting crime in order to attain a more competitive payoff. We show that this diversity of punishment leads to an explosion of complexity in the system, where the benefits and pitfalls of criminal behavior are revealed in the most unexpected ways. Due to the raise and fall of different alliances no less than six consecutive phase transitions occur in dependence on solely the temptation to succumb to criminal behavior, leading the population from ordinary people-dominated across punisher-dominated to crime-dominated phases, yet always failing to abolish crime completely.Comment: 9 two-column pages, 5 figures; accepted for publication in Scientific Report
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