Dr. Mohan Chaudhry Professor

Department of Mathematics & Computer Science

Papers presented at major conferences and symposia, and notable invited lectures

1. “On Queueing-Time Distributions in GI/D/1 and GI/D/c Systems in Discrete-Time”, CORS 2002 Annual Conference, Toronto. June 2002. Co-authors:  B.R.K. Kashyap, J. D. Kim.
2. “A Unified Way of Deriving Stationary Queue Lengths for a Broad Class of  FIFO Queues”, CORS 2002 Annual Conference, Toronto. June, 2002. INVITED. Also, presented an invited talk at the local CORS Section, Kingston. May 2002. Co-authors: N. K. Kim, K. C. Chae.
3. Invited talk: “Analytic and Computational Analyses of Discrete-Time Bulk-Service Queues with Variable Capacity and Finite and Infinite Waiting Spaces: Geo/G(Y)/1/M+B and Geo/G(Y)/1/infinity”,  CORS 2002 Annual Conference, Toronto. June 2002.
4. Invited lecture:  “Queueing Problems with MAP and Non-MAP Inputs,” 1st Seoul International Workshop on Queueing Theory, South Korea, 16-18 July 2001,
5. Invited lecture: “Analysis of finite-buffer queue with discrete-Markovian arrival process: D-MAP/Ga,b/1/N,” International Conference on Recent Developments in Statistics and Probability and their Applications, Delhi., Dec. 30, 2000-January 2, 2001.
6. Invited lecture: “Queue length distributions at various epochs in discrete-time D-MAP/G/1/N queue and their numerical evaluations,” International Conference on Recent Advances in Mathematical Sciences, 11T, Kharagpur, December 20-22, 2000.
7. Invited talk: “Analysis of a finite-buffer bulk-service queue with discrete-time Markovian arrival process: D-MAP/G(a,b)/1/N”, 2000 INFORMS-KORMS Seoul International Meeting, June 18-21.
8. Invited talk: “On the steady-state distributions of the numbers in the queue GeomX/G/1,” 15th Triennial Conference of IFORS, Beijing, 16-20 August, 1999.
9. Invited talk: “Transient solution for the number of busy servers for the discrete-time queue Geom(X)/G/4,” 15th Triennial Conference of IFORS, Beijing, 16-20 August, 1999.
10. Invited talk:  “On steady-state distributions of numbers in the queue Geom(X)/G/1 - An alternative approach,” April 9, 1999, Queen’s University. Also, given as a plenary talk at the International Conference on Stochastic Processes and their Applications, Cochin, 17-20 December 1999.
11. Plenary talk: “Modelling of discrete-time Queues - Recent advances and numerical computations” , International Conference on Stochastic Processes and Their Applications, Chennai, Jan 8-10, 1998.  
12. Invited talk: “Performance analysis of discrete-time finite-buffer batch arrival GI/Geom/1/N queues”, Indian Science Congress, Jan 2-8, 1998.
13. Invited talk: “Recent advances in discrete-time queues”, University of New South Wales, Australia, Dec 10,1997.
14. “Relations among limiting distributions of the number of customers at different epochs in discrete and continuous-times multiserver queues: GI/Geom/m and GI/M/m” , APORS Conference, Melbourne, Nov 29 - Dec 3 1997.
15. Plenary talk was given on the topic: “Transient solution of Markov chains having lower Heesenberg transition probability matrices and their applications,” International Conference on Stochastic Processes, Cochin, Dec 25-28, 1996. Also, chaired a session.
16. Invited talk: “Queue-length and Waiting-Time Distributions of Discrete-Time GI(X)/Geom/1 Queueing Systems with Early and Late Arrivals,” 14th IFORS Conf. 8-12 July, 1996.
17. Invited talk:  “On the Analysis of the Discrete-Time Geom(n)/G(n)/1/N Queue,” Conference Optimization Days, 13-15 May, 1996.
18. Invited talk:  “Transient Solutions of Markov Chains Having Lower Hessenberg Transition Probability Matrices and their Applications,” Int. Conf. on Pure and Applied Mathematics, November 1995.
19. “On the relations among the distributions at different epochs for the discrete time GI/Geom/1,” INFORMS International Conference, Singapore, June 28, 1995.
20. “Explicit results for the transient solution of M(n)X(n)/M(n)/1/N,” with JCW Van Ommeren, INFORMS International Conference, Singapore, June 28, 1995.
21. “On the relations among the distributions at different epochs for the discrete time GI/Geom/1 queue with JGC Templeton,” Management School of Xian Jiaotong University, Xian, China, 17 June 1995.
22. “On the queueing system GI(X)/Geom/1,” Institute of Applied Mathematics, The Chinese Academy of Sciences, China, June 14, 1995.
23. Invited lecture: “On computations of the mean & variance of the number of renewals: A unified approach,” University of Science & Technology, Hong Kong, June 8, 1995.
24. “On steady-state queue-size distributions of the discrete-time GI/G/I,” with T. Yang, International summer workshop on computations in single server queues, Hong Kong, June 22, 1995.
25. “Queue length and waiting time distributions of queueing systems with early and late arrivals,” with U.C. Gupta, International summer workshop on computations in single server queues, Hong Kong, June 22, 1995.
26. “First-passage-time and busy-period distributions of discrete-time Markovian queues:  Geom(n)/Geom(n)/1/N, CORS and optimization days, May 30-June 1, 1994.
27. “Simple and explicit transient solutions of discrete-time Markovian queues: Geom(n)/Geom(n)/r/N,” International Conference on Stochastic Processes and their Applications, The Netherlands, June 21—25, 1993.
28. “On exact computations of the mean and variance of the number of renewals: a unified approach,” INRIA/ORSA/TIMS/SMAI International Conference, France, June 16—18, 1993.
29. “Finding the first two moments of the number of renewals,” IASTED, International Conference, Washington, Nov. 4-6, 1992.
30. “Numerical computations of transient solutions in discrete-time for a class of problems in queueing theory,” - Queueing-Day Conference, University of Toronto, June 3, 1992.
31. “Computing Moments in the M/D/C System,” CORS 1992 Conference, June 1-3, 1992.
32. “Numerical Solutions of bulk-service queueing system:  M/Gy/1/N+B”, TIMS/ORSA Joint Conference, April 26-29, 1992.
33. “Finding roots of polynomial and transcendental equations,” University of Western Ontario, April 23, 1992.
34. Invited talks given at the Universidada de Estadual de Campinas during the period July 18-21, 1991.
35. “Exact computational analysis of distributions of numbers in systems for the M/G/I/N + 1  and GI/M/I/N + 1 Queues using roots”, TIMS International Conference, Rio de Janeiro, July 15-17, 1991.
36. “Stationary queueing‑time distribution in GI/R/1 systems: Explicit closed‑form analysis and exact computational results” , ORSA/TIMS Conference, October 29‑31, 1990.
37. “Computational analysis of the number in system and waiting‑time   distributions in  M/G/1” , CORS National Meeting, Ottawa, May 22‑24, 1990.
38. “Computational analysis of the number in system and waiting‑time  distributions in  MX/G/1 queues” , TIMS/ORSA Joint Conference, May 7‑9, 1990.
39. “Numerical rootfinding problems in probability modeling” , ORSA/TIMS Joint Conference, Oct. 16‑18, 1989.
40. “Computational analysis of steady‑state queueing time distribution in discrete  GI/G/1 queueing  systems” ,  ORSA/TIMS Joint Conference, Oct.  16‑18, 1989.
41. “Robustness of rootfinding in Queueing” , CORS/ORSA/TIMS Vancouver Joint Conference, May 8‑10, 1989.
42. Invited address titled, “Computing roots of a characteristic equations occurring in queueing and other stochastic processes” , International Conference on Computing and Information Science, McMaster University, April 23‑29,1989.
43. “Explicit results for the waiting time distribution in GI/G/1 queueing  systems” , Ontario Math meeting, Kingston, Ontario, October 1988.
44. “Computational analysis and PC demostration of GIX /M/1 and    GI/Er/1,  M/GY/1 and  Er/G/1”  , ORSA/TIMS Denver Conference, October 23‑26, 1988.
45. “Exact computations of system size distribution for single‑server bulk queues with random batch size and large parameter values” , a special interest conference on analysis and control of large scale stochastic systems, North Carolina, 23‑25 May, 1988.
46. “PC demonstration of the queueing system MX/D/c”, TIMS/ORSA conference, Washington, D.C., April 25‑27, 1988.
47. “Distributions of waiting times in models GIX/M/1  and  GI/EX/1”, TIMS / ORSA conference, Washington, D.C.,  April 25‑27, 1988.
48. “PC demonstration of a queueing system” , ORSA/TIMS conference, St. Louis, October 25‑28, 1987.
49. “Computational analysis of single‑server bulk‑service queues:  M/GY/1” , 1st International conference on Industrial and Applied Mathematics, Paris, France., June 29 ‑ July 3, 1987.
50. “Computational Experience with Bulk Queues” , The special interest conference on queueing networks and their applications,New Brunswick, NJ, January 7‑9, 1987
51. “PC programme demonstration:  GIX/M/1”, International TIMS XXVII conference, Australia, July 21‑23, 1986. With G. Brière.
52. “Numerical results for queueing model GIX/M1”, International TIMS XXVII conference, Australia, July 21‑23, 1986  With G. Brière.
53. Invited paper: “Steady‑state results on a multiserver queueing system”, Los Angeles TIMS/ORSA joint meeting, April 14 ‑ 16, 1986.
54. “An approximation for some bulk queuing systems” , 75th Ontario mathematics meeting, McMaster University, Feb. 14‑15, 1986.
55. “Computational analysis of single‑server bulk‑arrival queues  MX/G/1”, EURO VII congress, June 16‑25, 1985
56. Invited talk: “Computational analysis of single‑server bulk‑arrival queues”,  Applied Probability Group of ORSA/TIMS, January 7 ‑ 9, 1985.
57. “Steady‑state probabilities of some bulk and nonbulk queues; computer results with high parameter values” , XXVI International meeting of TIMS, June 17 ‑ 21, 1984.
58. Invitation to give a talk at the Asian Congress on Management Science, cybernetics and General Systems was declined. Congress was held in Delhi,  January 12 ‑17, 1984.
59. Invited lecture was given at the XIII international Conference on Stochastic Processes and Their Applications Banaras, December 17 ‑ 21, 1983.
60. “On two bulk‑service queueing models” , VI EURO Congress, Vienna, July 19 ‑ 22, 1983.
61. Invited paper: “On the queueing system GI/Ma,b/1” was presented at TIMS/ORSA meeting, Chicago, April 25 ‑ 27, 1983.  With B.R. Madill.
62. Invited talk : “On the versatility of the supplementary variable technique,”  Department of Mathematical Sciences, McMaster University, February 3, 1981.
63. Invited paper: “The queueing system  Ek/M(a,b)/1  and its numerical analysis”  , CORS‑TIMS‑ORSA joint meeting,  Toronto, May 3 ‑ 6, 1981. Co‑authored with G. Easton was presented.
64. “On the number in the system  GIX/M/1”, EURO IV Congress, Cambridge, England, 1980.
65. Invited talk : “On the link between the supplementary variable technique and the  imbedded Markov chain technique,”  Department of Industrial Engineering, University of Toronto, November 26, 1980.
66. “A unified approach to some results for the queueing system  M/Ga,b/1” ,  XXIV international meeting of the Institute of Management Sciences, Honolulu, June 18 ‑ 22, 1979.
67. “Some results for the queueing system  EXb/M/c”, EURO III Congress on Operations Research, Amsterdam, April 9 ‑ 11, 1979.
68. Invited talk:  “Some single server queueing systems with bulk arrivals or bulk services and their ramifications.”, Department of Management Sciences, University of Waterloo, February 9, 1979.
69. “The queueing system  MX /G/1 and its ramifications”,  50th Ontario Mathematics meeting,  Waterloo, February 10, 1979.
70. Invited talk: “Marriage between the supplementary variable technique and the Imbedded Markov Chain technique”, Indian Institute of Technology, Bombay, India, on August 21, 1978. This paper was also presented at the eighth Prague Conference, August 28 to September 1, 1978.
71. “The queueing system M/G/1” (with bulk service) in continuous time and its relation to the corresponding imbedded Markov Chain results”, The joint national meeting of ORSA/TIMS, San Francisco, May 9‑11, 1977.
72. “The queue M/GB/1”, 40th Ontario Mathematics Meeting, October 1976.
73. “Further discussions of the results on the queueing systems MX/M/C”, The joint meeting of ORSA/TIMS, Las Vegas, November 1975.  Co‑author: M.V. Cromie.
74. “Further results on the queueing systems  M/MX/C”, The joint meeting of ORSA/TIMS, Chicago, April 1975.  Co‑author: M.V. Cromie.
75. Invited lecture was given at the Department of Management Sciences, University of Waterloo, 1973.
76. Invited lecture was given at the Department of Mathematics, Queen's University, 1973.
77. Invited lectures were given at the Department of Mathematics, Indian Institute of Technology, India, during the summer, 1971.
78. “On the distribution of a number in a dual bulk queue”, Department of Mathematics, Queen's University, 1970.
79. A series of lectures was given to the staff and the graduate students of the Department of Industrial Engineering, University of Toronto, during the summer, 1970.
80. “Queueing problems with heterogeneous service phases”, summer research institute,  Queen's University, 1968.
81. “Queueing problems with arrivals depending on queue length and departures correlated”, 53rd session of the Indian Science Congress, 1966.