RAQS is a software
package for analyzing general queueing network models based on a two-moment
framework. It is a Windows application and is written in C++. It supports
instruction and research in queueing systems and is suitable for both
undergraduate and graduate students. RAQS was the final product of a project
that was funded by the National Science Foundation under the Engineering
Research Deployment Teaching Initiative Program (Grant No. DDM-9311357)
during 1993-94. Additional support was provided by the AT&T Foundation
through a grant to the Center for Computer Integrated Manufacturing. RAQS
is maintained by Dr. Kamath and his CCiMe graduate assistant, with a new
version released every two to three years as shown in the RAQS timeline.
1993-94 NSF grant initiates the
development of RAQS
1995 First full version of RAQS
available on the Web
1996 Version 2, a 32-bit version
of RAQS available on the Web
1998 Software fixes to
accommodate Windows 98, Second Edition
1999-2000 Development of a new GUI and
text file input option
2001 Version 3, called RAQS2001
available on the Web
RAQS implements the
parametric decomposition (PD) approach and its extensions for solving single
and multiclass open queueing networks. The PD approach was made popular by
Whitt’s Queueing Network Analyzer publications shown below.
- Segal, M. and W.
Whitt. 1989. A queueing network analyzer for manufacturing.
Proceedings of the 12th International Teletraffic Congress, Torino,
Italy, June 1988, 1146-1152.
- Whitt, W. 1983.
The queueing network analyzer. Bell Systems Technical J. 62
The following is an early publication that
describes the basic features of the RAQS software.
Kamath, M., S. Sivaramakrishnan, and G.
Shirhatti, 1995, “RAQS: A software package to support instruction and
research in queueing systems,” 4th Industrial Engineering Research
Conference Proceedings, pp. 944-953, IIE, Norcross, GA.
RAQS also implements the extension of the PD
approach to closed queueing networks and tandem finite buffer networks
developed by Prof. M. Kamath. Some of the publications and presentations
that document the PD approach for closed queueing networks and tandem finite
buffer networks are listed below.
Kamath, M., 1994, “Recent developments in modeling and performance analysis
tools for manufacturing systems,” In Computer Control of Flexible
Manufacturing Systems, (S. Joshi and J. Smith, Eds.), Chapman & Hall,
London, pp. 231-263.
Suri, R., J.L. Sanders, and M. Kamath, 1993, “Performance evaluation of
production net¬works,” in Handbooks in Operations Research and Management
Science, Vol. 4: Logistics of Production and Inventory, (S.C. Graves et al.,
Eds.), Elsevier Science Publishers, B.V., pp. 194-286.
Basnet, C. and M. Kamath, 1991, “A two-moment queueing network model for
flexible manufacturing systems with transport vehicles,” Proceedings of the
First Joint Conf. of the Operational Research Society of New Zealand & the
New Zealand Production and Inventory Control Society, pp. 7-12.
Kamath, M. and J.L. Sanders, 1991, “Modeling operator/workstation
interference in asynchronous automatic assembly systems," Discrete Event
Dynamic Systems: Theory and Applications, Vol. 1, pp. 93-124.
Kamath, M. 1990, “Analytical performance modeling of asynchronous automatic
assembly systems,” Proceedings of the 1990 International Industrial
Engineering Conference, IIE, Norcross, GA, pp. 557-562.
Kamath, M., R. Suri, and J.L. Sanders, 1988, “Analytical performance models
for closed loop flexible assembly systems,” The International Journal of
Flexible Manufacturing Systems, Vol. 1, pp. 51-84.
Kamath, M. and J.L. Sanders, 1987, “Analytical methods for performance
evaluation of large asynchronous automatic assembly systems,” Large Scale
Systems in Information and Decision Technologies, Vol. 12, No. 2, pp.
Kamath, M. and J.L. Sanders, 1986, “Analysis of asynchronous automatic
assembly systems with bottleneck stations,” SME-Systems I Conference Papers,
Kamath, M., S. Sivaramakrishnan, and G. Shirhatti, 1995, “A 2-moment
approach for solving multiclass closed queueing network models of
manufacturing systems,” INFORMS New Orleans Fall 1995.
Kamath, M. 1995, “RAQS: a software package for rapid analysis of queueing
systems,” INFORMS New Orleans Fall 1995.
Kamath, M.,1992, “A two-moment approximation for solving tandem queueing
networks with finite buffers,” ORSA/TIMS Joint National Meeting.
Kamath, M. and J.L. Sanders, 1989, “Operator/station interference models for
automatic assembly systems,” ORSA/TIMS Joint National Meeting.