A Brief Description of Our Queueing Network Modeling Work:

We model the human mind and behavioral system as a queueing network of information processing servers. Our modeling approach integrates theories and methods of mathematical psychology, computational cognitive modeling (procedure/production rule based), operations research, neuroscience, and experimental psychology.

As a mathematical model, our queueing network model is able to integrate a large number of existing mathematical models as special cases and to cover a wider range of phenomena. As a computational cognitive model, our model has a distinct position in modeling cognition: Cognition in our Queueing Network model is neither serial (ACT-R's position) nor relying on Executive Control (EPIC's position). It is a macro-architecture model with a few dozens of powerful processing units (like cortical zones or psychological functional modules), not a micro-structure connectionist neural network of a large number of neurons.

Our queueing network model has not only an underlying mathematical structure and rigor, but also computational power to generate/simulate behavior in real time. For example, it is able to steer a driving simulator in real time, while allowing us to visualize the internal information flows inside "the mind" while the "human" performs real world tasks such as driving--see
short movie clip (Best viewed with QuickTime).

Please see our publications on Queueing Network Modeling of Human Performance for more details. We warmly welcome your comments.

Journal Articles:

1. Liu, Y. (1996). 
"Queueing network modeling of elementary mental processes", 
Psychological Review, vol. 103, pp. 116-136.
 
2. Wu, C., and Liu, Y. (2008).
	"Queuing network modeling of the Psychological Refractory Period (PRP),"
	Psychological Review, to appear in Oct 2008 issue.
 
3. Liu, Y., Feyen, R., and Tsimhoni, O. (2006). 
	"Queueing Network-Model Human Processor (QN-MHP): A Computational Architecture for multitask performance in human-machine systems,"
	ACM Transactions on Computer-Human Interaction, vol. 13, no. 1, pp. 37-70.
 
4. Wu, C., and Liu, Y. (2008).
	"Queueing network modeling of transcription typing,"
	ACM Transactions on Computer Human Interaction, in May 2008 issue.

5. Liu, Y. (1997) 
"Queueing network modeling of human performance of concurrent spatial and verbal tasks
IEEE Transactions on Systems, Man, Cybernetics, vol. 27, pp. 195-207.
 
6. Wu, C., Liu, Y. , Walsh, C. (in press).
	"Queueing network modeling of a real-time psychophysiological index of mental workload--P300 in evoked brain potential (ERP),"
	IEEE Transactions on Systems, Man, and Cybernetics.
 
7. Lim, J., and Liu, Y. (in 3rd round review)
  "Reinforcement learning in eye movement: Modeling the influences of top-down and bottom-up processes,"
	IEEE Transactions on Systems, Man, and Cybernetics.
 
8. Wu, C., and Liu, Y. (2007).
	"Queueing network modeling of driver performance and workload,"  
	IEEE Transactions on Intelligent Transportation Systems, Vol. 8, No. 3, pp. 528-537.
 
9. Wu, C., Tsimhoni, O., and Liu, Y. (in press).
	"Development of an adaptive workload management system with the Queuing Network-Model Human Processor (QN-MHP),"
	IEEE Transactions on Intelligent Transportation Systems, in press.
 
10. Lim, J., Tsimhoni, O., and Liu, Y. (in 3rd round review)
	"Investigation of driver performance with night vision and pedestrian detection systems, Part 1: Empirical study on visual cluster and search behavior."
 
11. Lim, J., Tsimhoni, O., and Liu, Y. (in 3rd round review)
	"Investigation of driver performance with night vision and pedestrian detection systems, Part 2: Queueing network performance modeling."
 
12. Wu, C., and Liu, Y. (2007).
	"Interface makeover of a software tool for modeling human performance and workload,"  
	Ergonomics in Design, Spring 2007.
 
13. Wu, C., and Liu, Y. (2008).
	"Development and evaluation of a software package for predicting human performance and workload in human-machine interface design and evaluation,"
	Computers and Industrial Engineering. in press.


Recent Conference Papers and Tech Reports:
 

1.	Liu, Y. (2006)
	"QN-ACES: A Biologically-inspired cognitive architecture (BICA) integrating queueing network (QN) 
	and ACT-R, CAPS, EPIC, Soar (ACES) architectures for multitask cognitive modeling: Part I," Dept of IOE Tech Report 06-07.
 
2. 	Liu, Y. (2007).
	"QN-RMD--Queueing network (QN) modeling of mental architecture, response time, and response accuracy: 
	Reflected multidimensional diffusions (RMD)" 
	Proceedings of the 2007 International Conference on Cognitive Modeling (ICCM-2004).
 
3. 	Berman, M., Liu, Y., and Wu, C. (2007)
	"A 3-node queuing network template for modeling neural and cognitive phenomena,"
	Proceedings of the 2007 International Conference on Cognitive Modeling (ICCM-2004).
 
4. 	Wu, C., Tsimhoni, O., and Liu, Y. (2007).
	"Development of a driver workload management system with the Queuing Network-Model Human Processor,"
	Proceedings of the 51st Annual Conference of the Human Factors and Ergonomics Society.
	
5.	Wu, C., and Liu, Y. (2006).
	"Queuing Network Modeling of Age Differences in driver workload and performance," 
	Proceedings of the 50th Annual Conference of the Human Factors and Ergonomics Society.
 
6. 	Wu, C., and Liu, Y. (2006).
	"Modeling fMRI BOLD Signal and Reaction Time of a dual task with the queueing network approach,"
	Proceedings of the 28th Annual Conference of the Cognitive Science Society.
 
7.	Wu, C., and Liu, Y. (2006).
	"Queueing network modeling of driver performance and mental workload,"
	Proceedings of the 50th Annual Conference of the Human Factors and Ergonomics Society.
 
8.	Wu, C., and Liu, Y. (2006).
	"Queuing Network Modeling of Reaction time, response accuracy, and Stimulus-Lateralized Readiness Potential Onset Time in a dual task," 
	Proceedings of the 28th Annual Conference of the Cognitive Science Society.
 
9.	Wu, C., and Liu, Y. (2006).
	"Queueing network modeling of the P300 component of ERP as an index of workload,"
	Proceedings of the 50th Annual Conference of the Human Factors and Ergonomics Society.
 
10.	Lim, J., and Liu, Y. (2006).
	"A reinforcement learning model of the cyclic top-down and bottom-up processes in eye movements,"
	Proceedings of the 50th Annual Conference of the Human Factors and Ergonomics Society.
 
11.	Liu, Y. (2005).
	"QN-RMD--Queueing network (QN) modeling of mental architecture, response time, and response accuracy: 
	Reflected multidimensional diffusions (RMD): Part I." Dept of IOE Tech Report 05-11.
 
12.	Wu, C., and Liu, Y. (2004a). 
	"Modeling Psychological Refractory Period (PRP)and Practice Effect on PRP with Queueing Networks and Reinforcement Learning Algorithms,"
	Proceedings of the 2004 International Conference on Cognitive Modeling (ICCM-2004).
 
13.	Wu, C., and Liu, Y. (2004b). 
	"Modeling Behavioral and Brain Imaging Phenomena in Transcription Typing with Queueing Networks and Reinforcement Learning Algorithms,"
	Proceedings of the 2004 International Conference on Cognitive Modeling (ICCM-2004).
 
14.	Wu, C., and Liu, Y. (2004c). 
	"Modeling Human Transcription Typing with QN-MHP (Queueing Network - Model Human Processor),"
	Proceedings of the 48th Annual Conference of the Human Factors and Ergonomics Society.
 
15.	Lim, J. and Liu, Y. (2004a). 
	"A Queueing Network Model for Eye Movement,"
	Proceedings of the 2004 International Conference on Cognitive Modeling (ICCM-2004).
 
16.	Lim, J., and Liu, Y. (2004b). 
	"A Queueing Network Model for Visual Search and Menu Selection," 
	Proceedings of the 48th Annual Conference of the Human Factors and Ergonomics Society.
 
17.	Tsimhoni, O., and Liu, Y. (2003), 
	“Modeling steering with the Queueing Network-Model Human Processor (QN-MHP),” 
	Proceedings of the 47th Annual Conference of the Human Factors and Ergonomics Society. 
	Winner of Human Factors and Ergonomics Surface Transportation Best Student Paper Award.
 
18.	Tsimhoni, O., and Liu, Y. (2003), 
	“Steering a Driving Simulator using the Queueing Network-Model Human Processor (QN-MHP),” 
	Proceedings of the 2nd International Driving Symposium on Human Factors in Driver Assessment, Training, and Vehicle Design.
 
19.	Feyen, R., and Liu, Y. (2001), 
	“Modeling task performance using the queueing network model human processor (QN-MHP),” 
	Proceedings of the International Conference on Cognitive Modeling.
 
20.	Feyen, R., and Liu, Y. (2001), 
	“The Queueing Network-Model Human Processor (QN-MHP): An engineering approach for modeling cognitive performance,” 
	Proceedings of the 45th Annual Conference of the Human Factors and Ergonomics Society.
 
21.	Feyen, R., and Liu, Y., Hoffmeister, D., Zobel, G., Rupp, G., Bhise, V., (2000), 
	“Effects of shared controls and system modes on driver performance and subjective evaluation of workload,” 
	Proceedings of Human Factors and Ergonomics Society 44th Annual Conference.
 
22.	Feyen, R., and Liu, Y., (2000), 
	“Age differences in instrument panel use,” 
	Proceedings of Human Factors and Ergonomics Society 44th Annual Conference.
 
23.	Feyen, R., and Liu, Y., (1999), 
	“Queueing Network Model Human Processor (QN-MHP): An engineering model for human performance of multiple tasks”, 
	Proceedings of the 4th International Conference on Industrial Engineering Theory, Applications, and Practice, 
	Nov. 17-20, 1999, San Antonio Texas, USA.