G. Greenman

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— Agreed message delivery is an important service in distributed systems, especially when dealing with fault-tolerant applications. This work studies factors influencing protocols that provide global order in Wide Area Networks. Performance evaluation in real network conditions was conducted in order to compare two recently published algorithms. It was(More)
Two enhancements to the combinatorial geometry (CG) particle tracker in the Mercury Monte Carlo transport code are presented. The first enhancement is a hybrid particle tracker wherein a mesh region is embedded within a CG region. This method permits efficient calculations of problems with contain both large-scale heterogeneous and homogeneous regions. The(More)
Many distributed systems may be limited in their performance by the number of transactions they are able to support per unit of time. In order to achieve fault tolerance and to boost a system's performance, active state machine replication is frequently used. It employs total ordering service to keep the state of replicas synchronized. In this paper, we(More)
A Monte Carlo method for calculating the probability of initiating a self-sustaining neutron chain reaction has been developed. In contrast to deterministic codes which solve a non-linear, adjoint form of the Boltzmann equation to calculate initiation probability, this new method solves the forward (standard) form of the equation using a modified source(More)
The new physics, algorithmic and computer science capabilities of the Mercury general-purpose Monte Carlo particle transport code are discussed. The new physics and algorithmic features include in-line energy deposition and isotopic depletion, significant enhancements to the tally and source capabilities, diagnostic ray-traced particles, support for(More)
Illinois Consortium on Drug Policy The Illinois Consortium on Drug Policy is a project established in 2005 that is housed at Roosevelt University's Institute for Metropolitan Affairs in Chicago, Illinois. Mission The Consortium's primary objectives are to promote discussion of alternatives to Illinois' current drug policies and to serve as a forum for the(More)
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