HLA-based Simulation System Research Articles

Time Series-Oriented Load Prediction Model and Migration Policies for Distributed Simulation Systems

HLA-based simulation systems are prone to load imbalances due to lack management of shared resources in distributed environments. Such imbalances lead these simulations to exhibit performance loss in terms of execution time. As a result, many dynamic load balancing systems have been introduced to manage distributed load. These systems use specific methods, depending on load or application characteristics, to perform the required balancing. Load prediction is a technique that has been used extensively to enhance load redistribution heuristics towards preventing load imbalances. In this paper, several efficient Time Series model variants are presented and used to enhance prediction precision for large-scale distributed simulation-based systems. These variants are proposed to extend and correct the issues originating from the implementation of Holt's model for time series in the predictive module of a dynamic load balancing system for HLA-based distributed simulations. A set of migration decision-making techniques is also proposed to enable a prediction-based load balancing system to be independent of any prediction model, promoting a more modular construction.

A Modified Statistical Process Control Approach for Warm-up Selection in Discrete-Event Simulation

HLA-based simulation systems are multivariate discrete-event simulation systems, and sometimes with small samples in essential, for which exists initial transient issue. Simulation models begin in fixed initial values, which are always different from the steady state values. A variety of selection methods have been developed these years, but no one method could be recommended above others. Among these methods, the familiar statistical process control method is a popular way to deal with the warm-up selection, with the deficiency for multivariate and small samples. Based on SPC, individuals and moving range, multivariate exponentially weighted moving average chart for Individuals and Hotelling T2 method, a modified SPC method is proposed. The case of military domain simulation scenario and some empirical experiments, illustrate the validity of the modified SPC method.

Research of dynamic scheduling method for the air-to-ground warfare simulation system based on grid

The military field has been a strong demand for automatic management of the running of simulation, and the sharing of simulation resources and so on. Aimed at the puzzles in current HLA-based simulation system, and with the combination of a new grid idea, a framework of simulation grid has been presented. This article is absorbed in the aim how to schedule the task under simulation grid environment and explore the dynamic dispatch to the parallel tasks in the federation entity level. Finally a mended heuristic scheduling algorithm has been designed. This algorithm dynamically adjusted decision-making through using the information of systematical real-time operating status, be able to making a timely response dynamically according to the changes of the characteristics of simulation system, re-achieve balance and improve the system performance, fault-tolerant and load-balance ability according to the adjustment of the dynamic fluctuations of the loading. Taking the air-to-ground warfare simulation system as an example, simulation results verify that the method is effective and useful, and it could contribute to enhance using resource quotient and construct the large-scale military simulation applications.