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WSC 2005 Final Abstracts |
Web-enabled Simulation Technologies Track
Wednesday 8:30:00 AM 10:00:00 AM
Grid Computing and Distributed
Chair: Richard Kilgore (SML Simulation Services)
Simulation of Grid Computing Infrastructure:
Challenges and Solutions
Sugato Bagchi (IBM T. J. Watson Research
Center)
Abstract:
Recent advances in middleware technologies such as grid
computing have provided IT architects with the ability to design
infrastructures that are more flexible and less dedicated to specific
application workloads. However, the capabilities of design and analysis tools
that IT architects use have not kept pace. In this paper, we describe our
progress in developing an IT infrastructure modeling environment that supports
an extensible set of analysis tools. We focus in particular on a
discrete-event simulator for analyzing the performance of computational
workloads that are running on a grid. The unique modeling requirements and
challenges presented by the grid computing infrastructure domain are
discussed. Efficient event queue management and other simulation techniques to
address these challenges are developed. Finally, we position the role of
simulation analysis in the larger context of estimating the business and
financial returns from grid computing investments.
Time Management in Distributed Factory Simulation, a
Case Study Using HLA
Ke Wang, Sheng Xu, and Leon F. McGinnis
(Georgia Institute of Technology)
Abstract:
Distributed simulation is attractive for modeling large
scale manufacturing systems. However, synchronization requirements present
distinct challenges in designing and implementing a suitable modeling
structure. Our experience in building a distributed simulation model for 300mm
wafer fab using the High Level Architecture (HLA) shows that time management
should be considered at both the design and the implementation stages. This
paper proposes an optimistic-conservative synchronization scheme by using
model specific information at the implementation stage. Computational results
are then presented to show that properly implemented distributed factory
simulation can achieve significant reduction in model execution time.
Data Consistency in a Large-Scale Runtime
Infrastructure
Buquan Liu, Huaimin Wang, and Yiping Yao (National
University of Defense Technology)
Abstract:
In order to support large-scale distributed simulation,
we have developed a RTI called StarLink+ with particular architecture which is
compliant with IEEE 1516. StarLink+ is composed of a Central RTI server and
multiple Local RTI servers. Each Local RTI server manages multiple federates.
Data consistency has great influence on RTI's performance and scale. In
StarLink+, only a small portion of data must be globally consistent for all
Local RTI servers. However, a great amount of data is not consistent for
different Local RTI servers. This paper focuses on the research of data
consistency about a variety of data in StarLink+. On the one hand, we
introduce the fully consistent data such as object name designation and handle
assignment; on the other hand, we also study the partly consistent data such
as publication and subscription, ownership transfer, and time management.
Wednesday 10:30:00 AM 12:00:00 PM
Web-enabled Applications
Chair: Sugato Baghi (IBM T. J. Watson Research
Center)
Initialization of Online Simulation
Models
Andre Hanisch and Juri Tolujew (Fraunhofer Institute IFF)
and Thomas Schulze (University of Magdeburg)
Abstract:
Online simulation is a relatively new control strategy
for short-term decision-making for the control and management of processes in
existing systems. In contrast to traditional “non-terminating” simulation,
online simulation cannot use a transient phase to tune the models because the
simulation models need to run very quickly and also need to deliver results
right from the start. In this context, the initialization of such online
simulation models represents a special problem. It requires mapping between
the system-describing variables in the model and the available data in the
real system. This paper examines two different methods of initialization.
Special emphasis is placed on explaining the approach of parent model
synchronization. Both initialization approaches are transferred to the context
of analyzing and forecasting pedestrian flows in a public building. A first
prototypical implementation in SLX is also briefly presented.
Addressing Complexity Using Distributed Simulation:
A Case Study in Spaceport Modeling
Jaebok Park, Reinaldo Moraga,
and Luis Rabelo (University of Central Florida), Jeffrey W. Dawson (University
of central Florida) and Mario Marin and Jose Sepulveda (University of Central
Florida)
Abstract:
As the size, complexity, and functionality of systems
to model and simulate continue to increase, benefits such as interoperability
and reusability enabled by distributed discrete-event simulation are of
interest, especially for distributed manufacturing and enterprise engineering.
The High Level Architecture (HLA), a standard distributed simulation
environment, is one technology that enables the interconnection of distributed
model components. Many applications in industry are developed by a variety of
Commercial Off-The-Shelf (COTS) simulation tools, which require some form of
gateway to integrate the models into the HLA component-based simulation. This
paper summarizes a study conducted to integrate COTS simulation models using
gateway tools and visualization of the system states running as part of other
simulation models under HLA. The study focused on the prototype of a virtual
engineering environment, called the Virtual Test Bed, designed to analyze
operations of current and future space vehicles, spaceports, and ranges as a
distributed simulation environment.
Flexible Integration of XML into Modeling and
Simulation Systems
Mathias Roehl and Adelinde M. Uhrmacher
(University of Rostock)
Abstract:
As the effort towards standardization of formalism
representations increases so does the need for verifying whether models do or
do not follow a standard. Data binding allows to systematically exploit XML
and its associated technologies for modeling and simulation purposes. Based on
the schema definition of a formalism, a binding compiler generates model
classes that support the user in constructing models according to the
formalism. Most constraints can be checked automatically, few require separate
efforts by the designer of the simulation system. Although simulators could be
build for these declarative model descriptions, they would be hardly
efficient. To this end, a separate transformation component is required. In
this overall process, both model specifications that are consistent with a
formalism definition and models that can be executed efficiently are supported
equally.