14818835
An empirical evaluation of several methods to select the best system
Simulation is an important tool for comparing the performance of several alternative systems. There is therefore significant interest in procedures that efficiently select the best system, where best is defined by the maximum or minimum expected simulation output. In this paper, we examine both two-stage and sequential procedures that represent three structurally different modeling methodologies for allocating simulation replications to identify the best system, and we evaluate them empirically with respect to several measures of effectiveness. Empirical evidence suggests that sequential procedures perform better than their two-stage counterparts, including a heuristic sequential variation on Rinott's procedure. Further, there appears to be significant benefit to using procedures based on a Bayesian, average-case analysis as opposed to the statistically-conservative indifference-zone formulation.
9048744
Web-based simulation experiments
The use of the World Wide Web and Java-based mobile code provides new opportunities for distributed simulation. First, the infrastructure provided by the Internet eliminates the need for multiprocessor hardware, making it feasible to distribute simulation models over different hardware platforms through the Internet. Second, "Internet-aware" mobile Java code makes the applications fully portable and reusable. These enabling technologies are already exploited for distributed simulation modeling. This paper reports on the preliminary results of an on-going effort to construct a parallel discrete event simulation support system to distribute simulation experiments over the Internet with a view on simulation optimization. A research prototype for ranking and selection problems is described. The overall project goals are discussed.
204988011
A class of additive multiplicative graph functions
For a fixed graph G, the capacity function for G, Po, is defined by Pc(H)= lim,__,®[yo(H')] TM, where y6(H) is the maximum number of disjoint G's in H. In [2], Hsu proved that Pr2 can be viewed as a lower bound for multiplicative increasing graph functions. But it was not known whether Pr2 is multiplicative or not. In this paper, we prove that Pc is multiplicative and additive for some graphs G which include K2. Some properties of Pc are also discussed in this paper.
16272778
The Maximum Partition Matching Problem with Applications
Let ${\cal S} = {C1, C2, . . . , Ck}$ be a collection of pairwise disjoint subsets of U = { 1, 2, . . . , n} such that $\bigcup_{i = 1}^k Ci = U. A partition matching of $\cal S$ consists of two subsets {a1, . . . , am} and {b1, . . ., bm} of U together with a sequence of distinct partitions of $\cal S$: $({\cal A}_1, {\cal B}_1), \ldots, ({\cal A}_m, {\cal B}_m)$ such that ai is contained in a subset in the collection ${\cal A}_i$ and bi is contained in a subset in the collection ${\cal B}_i$ for all i = 1, . . . , m. An efficient algorithm is developed that constructs a maximum partition matching for a given collection $\cal S$. The algorithm can be used to construct optimal parallel routing between two nodes in interconnection networks.
12948988
Parallelization of Multiple Genome Alignment
In this work, we implement a genome alignment system which applies parallelization schemes to the ClustalW algorithm and the interface of database querying. Parallel construction of the distance matrices and parallelization of progressive alignment in the ClustalW algorithm are performed on PC-based Linux cluster with message-passing interface libraries. Achieved experiments show good speedup and significant parallel performance.
260704
An implementation of parallel dynamic load balancing for adaptive computing in VLSI device simulation
A new parallel semiconductor device simulation using the dynamic load balancing approach is presented. This semiconductor device simulation based on adaptive finite volume error estimation, and monotone iterative methods has been developed and implemented on a Linux-cluster with MPI library. Two different parallel versions of the algorithm to perform a complete device simulation are proposed. The first one is a dynamic parallel domain decomposition approach. The second version is a parallel current-voltage characteristic points simulation. The implementation shows that a well-designed load balancing simulation can reduce the execution time up to an order of magnitude. Compared with the measured data, numerical simulations on P-N diode, N-MOSFET, and DTMOS devices are presented to show the accuracy and efficiency of the method.
43110
A study of self-adjusting quality of service control schemes
We report simulation methods and results for analyzing a self-adjusting quality of service (QoS) control scheme for multimedia/telecommunication systems based on resource reservation. We study the case in which high priority clients' QoS requirement is not changed throughout the service period, while low priority clients' QoS may be adjusted by the system between the maximum and minimum QoS levels specified in order to adapt to the load of the system. The goal of the system design is to optimize the system reward as a result of servicing clients with different QoS and reward/penalty requirements. A QoS manager in these systems can do a table lookup operation using the simulation result reported to optimize the system total reward dynamically in response to changing workloads during the run time. The simulation result is particularly applicable to multimedia and telecommunication systems in which dynamic QoS negotiation/renegotiation is used as a mechanism to optimize the overall system performance.