**Research Interests**

Applied Stochastic Modeling

Applied Statistics

Applied Probability

Queues

Inventory

Reliability

Healthcare Modeling

Simulation

**Education**

B.S. Mathematics, University of Madras, Madras, India 1973

M.S. Statistics, University of Madras, Madras, India 1975

Ph.D. Operations Research, University of Delaware, Newark, DE 1983

**Experience**

Head and Professor, Department of Industrial and Manufacturing Engineering, Kettering University, 2014-present

Interim Department Head & Professor, Kettering University, Flint, MI, 2013-2014

Professor, Kettering University, Flint, MI, 1999-present

Visiting Faculty, University of Madrid, Madrid, Spain, 2005

Consultant, STI Inc., Ohio, 2004-2005

Visiting Faculty, University of Science & Technology, Cochin, India, 2004

Consultant, FANUC, Michigan, 2003

Visiting Faculty, Victoria University of Wellington, Wellington, New Zealand, 2003

Operations Research Group Manager, General Motors, Pontiac, MI, 2000-2001

Consultant, PCE, 1998-2000

Sloan Fellow, FORD, 1997

Consultant, GM, 1990-1992

Associate Professor, GMI Engineering & Management Institute, Flint, MI, 1986-1990

Lilly Fellowship, UPS, 1988

Assistant Professor, GMI Engineering & Management Institute, Flint, MI, 1983-1986

Research Assistant, University of Delaware, Newark, DE, 1981-1983

Teaching Assistant, University of Delaware, Newark, DE, 1978-1981

Research Fellow, University of Madras, Madras, India, 1976-1978

**Selected Publications**

M.F. Neuts and S. Chakravarthy. A Single Server Queue with Platooned Arrivals and Phase Type Services. European J. of Operational Research, 8, 379-389, 1981.

S. Chakravarthy. Reliability Analysis of a Parallel System with Exponential Life Times and Phase Type Repairs. OR Spektrum, 5, 25-32, 1983.

S. Chakravarthy. On the Optimal Control Problem of a Single Server Queueing System. J. of Optimization Theory and its Applications, 41, 317-325, 1983.

S. Chakravarthy. A Stochastic Model for Two Servers Sharing a Common Tool Magazine and its Analysis. Mathematical Modelling, 6, 307-332, 1985.

S. Chakravarthy. A Single Machine Scheduling Problem with Random Processing Times. Naval Research Logistics Quarterly, 33, 391-397, 1986.

S. Chakravarthy. On Two Cyclic Exponential Machines Sharing a Common Tool Magazine. American Journal of Mathematical and Management Sciences, Vol. 7, 205-232, 1987.

S. Chakravarthy. Analysis of Production Line Systems with Two Unreliable Machines with Phase Type Processing Times and a Finite Storage Buffer. Stochastic Models, 3, 369-391, 1987.

S. Chakravarthy, J.R. Pimentel and K.V. Ravi. A Flow and Error Control Model with Phase Type Timeout Periods. Proceedings of the IEEE Workshop on Factory Communications, March 1987, 179-197.

S. Chakravarthy and Marcel F. Neuts. Algorithms for the Design of Finite Capacity Service Units. Naval Research Logistics, 36, 147-165, 1989.

S. Chakravarthy and R. Parthasarathy. A Finite Capacity Queueing Model with Primary and Secondary Jobs. Computers and Industrial Engineering, 16, 97-108, 1989.

S. Chakravarthy and K.V. Ravi. A Stochastic Model for a Computer Communication Network Node with Phase Type Timeout Periods. Chapter 14 in Numerical Solutions of Markov Chains, Marcel Dekker 1991.

S. Chakravarthy. A Finite Capacity Dynamic Priority Queueing Model. Computers and Industrial Engineering, 22, 369-385, 1992.

S. Chakravarthy A Finite Capacity GI/PH/1 Queue with Group Services. Naval Research Logistics 39, 345-357, 1992.

S. Chakravarthy Analysis of a Finite MAP/G/1 Queue with Group Services. Queuing Systems: Theory and Applications, 13, 385-407, 1993.

S. Chakravarthy A Finite Capacity Queuing Network with Single and Multiple Processing Nodes. Queueing Networks with Finite Capacity, edited by R.F. Onvural and I.F. Akyildiz, 197-211, 1993, North-Holland, Netherlands.

S. Chakravarthy and A.S. Alfa. A Multi-server Queue with Markovian Arrivals and Group Services with Thresholds Naval Research Logistics, 40, 811-827, 1993.

S. Chakravarthy. Finite Capacity Queuing Models in Manufacturing and Production Systems. Proceedings of the 1994 NSF Design and Manufacturing Grantees Conference, 253-254, 1994.

A.S. Alfa and S. Chakravarthy. A Discrete Queue with the Markovian Arrival Process and Phase Type Primary and Secondary Services. Stochastic Models, 10, 437-451, 1994.

S. Chakravarthy and A.S. Alfa. A Finite Capacity Queue with Markovian Arrivals and Two Servers with Group Services. Journal of Applied Mathematics and Stochastic Analysis 7, 161-178, 1994.

S. Chakravarthy and S.Y. Lee. An Optimization Problem in a Finite Capacity PH/PH/1 Queue with Group Services. Stochastic Models, Optimization Techniques and Computer Applications, edited by G. V. Krishna Reddy, et al., 3-13, 1994.

S. Chakravarthy. Markovian Arrival Processes in Manufacturing and Production Systems. Proceedings of the 1995 NSF Design and Manufacturing Grantees Conference, 185-186, 1995.

A.S. Alfa, K.L. Dolhun, and S. Chakravarthy. A Discrete Single Server Queue with Markovian Arrivals and Phase Type Group Services . Journal of Applied Mathematics and Stochastic Analysis, 8, 151-176, 1995.

S. Chakravarthy and T. Dimitrova. Service Control of a Queueing System with Nonrenewal Arrivals and Phase Type Services. Proceedings of the International Mathematica Symposium, 93-102, 1995.

S. Chakravarthy Two Finite Queues in Series with Nonrenewal Input and Group Services. Proceedings of the Seventh International Symposium on Applied Stochastic Models and Data Analysis, 78-87, 1995.

S. Chakravarthy, S. Chukova and B. Dimitrov A Stochastic Model for Resequencing of Messages. Proceedings of the Second International IEMS Conference, 601-606, 1995.

S. Chakravarthy Analysis of the MAP/PH/1/K Queue with Service Control. Applied Stochastic Models and Data Analysis, 12, 179-191, 1996.

S. R. Chakravarthy and A. S. Alfa. A Production Capacity Queuing Model with Parallel Servers and Group Services. Advances in Industrial Engineering Applications and Practice I, 1114-1119, 1996.

S. R. Chakravarthy and A. S. Alfa. Matrix-Analytic Methods in Stochastic Models. Marcel Dekker, New York, 1997.

S. R. Chakravarthy and S. Kanchi. Performance Evaluation of a Parallel System First International Conference on Operations and Quantitative Management, 1997.

S. R. Chakravarthy and A. Agarwal. Analytic Comparison of Functional and Cellular Manufacturing Systems with Markovian Arrival Process. First International Conference on Operations and Quantitative Management, 1997.

S. R. Chakravarthy and L. Bin. Performance Analysis of a Resequencing Model in Telecommunications Network. Fifth International Conference on Telecommunication Systems, 633-652, 1997.

S. R. Chakravarthy and L. Bin. A Finite Capacity Queue with Nonrenewal Input and Exponential Dynamic Group Services. ORSA Journal on Computing, 9, 276-287, 1997.

S. R. Chakravarthy and T. Sashisekaran. Two Parallel Finite Queues with Simultaneous Services and Markovian Arrivals. Journal of Applied Mathematics and Stochastic Analysis, 10, 383-405, 1997.

A.S. Alfa and S. R. Chakravarthy. Advances in Matrix-Analytic Methods for Stochastic Models, Notable Publications Inc, New Jersey, 1998.

S. R. Chakravarthy, S. Chukova and B. Dimitrov. Analysis of MAP/M/2/K Queueing Model with Resequencing. Performance Evaluation, 31, 211-228, 1998.

S. R. Chakravarthy. Analysis of a Priority Polling System with Group Services. Stochastic Models, 14, 25-49, 1998.

S. R. Chakravarthy and S. Thiagarajan A stochastic model for a hysteresis based priority queueing strategy for ATM networks with batch arrivals – Theory. Proceedings of the Third IEEE Symposium on Computers and Communications, 530-536, 1998.

S. R. Chakravarthy. A Finite Capacity Queueing Network with Two Parallel Exponential Servers and Secondary Group Services of Phase Type. Stochastic Processes and Their Applications, Eds. A. Vijayakumar and M. Sreenivasan, 177-185, 1999.

D.A. Bini, S. R. Chakravarthy and B. Meini. A New Algorithm for the Design of Finite Capacity Service Units. Proceedings of the Third international Conference on the Numerical Solution of Markov Chains, Saragoza, Spain, 1999.

S. R. Chakravarthy. Analysis of a Multi-server Queue with Batch Markovian Arrivals and Group Services. Engineering Simulation, 18, 51-66, 2000.

D.A. Bini, S. R. Chakravarthy and B. Meini. Control of BMAP/PH/1/K Queue with Group Services. Advances in Algorithmic Methods in Stochastic Models, Eds., G. Latouche and P. Taylor, Notable Publications Inc., 57-72, 2000.

B. Dimitrov, S. Chukova, and S. R. Chakravarthy A Simple Unreliable Service Model Characterizes Exponential Distribution. Kuwait Journal of Science and Engineering, 28, 203-213, 2001.

S. R. Chakravarthy. The Batch Markovian Arrival Process: A Review and Future Work. In Advances in Probability Theory and Stochastic Processes, Eds., A. Krishnamoorthy, et al., 21-49, 2001, Notable Publications, Inc., New Jersey.

S. R. Chakravarthy and A.S. Alfa. Overload Control of a Finite Buffer Discrete Queue. In Advances in Probability Theory and Stochastic Processes, Eds., A. Krishnamoorthy, et al., 1-12, 2001, Notable Publications, Inc., New Jersey.

S. R. Chakravarthy, A. Krishnamoorthy and P.V. Ushakumari. A k-out-of-n Reliability System with an Unreliable Server and Phase Type Repairs and Services: The (N, T) Policy. Journal of Applied Mathematics and Stochastic Analysis, 14, 361-380, 2001.

S. R. Chakravarthy and A. Dudin. A Batch Markovian Queue with a Variable Number of Servers and Group Services. In Matrix-Analytic Methods – Theory and Applications, Eds., G. Latouche and P. Taylor, 63-88, 2002, World Scientific Publishing Co., Singapore.

A. Dudin and S. R. Chakravarthy. Optimal Hysteretic Control for the BMAP/G/1 with Single and Group Service Modes. Annals of Operations Research, 112, 153-169, 2002.

S. R. Chakravarthy and A. Dudin. A Single Sever Retrial Queuing Model with Batch Arrivals and Group Services. Advances in Stochastic Modelling, Eds., J.R. Artalejo and A. Krishnamoorthy, 1-21, 2002, Notable Publications, Inc., New Jersey.

S. R. Chakravarthy and A. Dudin. A Multi-server Retrial Queue with BMAP Arrivals and Group Services. Queuing Systems: Theory and Applications, 42, 5-31, 2002.

S. R. Chakravarthy and A. Dudin. Analysis of a Retrial Queuing Model with MAP Arrivals and Two Types of Customers. Mathematical and Computer Modelling, 37, 343-363, 2003.

S. R. Chakravarthy Analysis of a Machine Repair Problem with an Unreliable Server and Phase Type Repairs and Services (with A. Agarwal). Naval Research Logistics, 50, 462-480, 2003.

S. R. Chakravarthy Multi-threshold Control of the BMAP/SM/1/K Queue with Group Services (with A. Dudin). Journal of Applied Mathematics and Stochastic Analysis, 16, 327-348, 2003.

S. R. Chakravarthy and Paul D. Young. A Circuit Testing Assembly Line Model with Markovian Arrival Process. Journal of Mathematical Sciences, 2, 10-33, 2003.

S. R. Chakravarthy. How to Increase the Ability of a Student to Learn. Proceedings of the 2004 American Society for Engineering Education Annual Conference and Exposition.

S. R. Chakravarthy and Jacob Daniel. A Markovian Inventory System with Random Shelf Time and Back Orders. Computers and Industrial Engineering, 47, 315-337, 2004.

S. R. Chakravarthy, V. I. Klimenok and A. N. Dudin. A Multi-server Markovian Queueing Model with Primary and Secondary Services. Proceedings of the eighteenth Belarussian winter workshop in queueing theory, 70-79, 2005.

S. R. Chakravarthy and S.R. Agnihothri. Optimal Workforce Mix in Service Systems with Two Types of Customers. Production and Operations Management, 14, 218-231, 2005.

S. R. Chakravarthy and S. Chukova A Finite Capacity Resequencing Model with Markovian Arrivals. Asia-Pacific Journal of Operational Research, 22, 409-443, 2005.

V. I. Klimenok, S. R. Chakravarthy and A. N. Dudin. Algorithmic Analysis of a Multi-Server Markovian Queue with Primary And Secondary Services. Computers and Mathematics with Applications, 50, 1251-1270, 2005.

S. R. Chakravarthy and S. Thiagarajan. Analysis of a Hysteresis based Queueing Strategy for ATM Networks with batch Markovian Arrivals – Numerical Results. Proceedings of the Third National Conference on Mathematical and Computational Models, Eds., R. Arumuganathan and R. Nadarajan, 109-135, 2005.

S. R. Chakravarthy and S. Kanchi. A Stochastic Model for a Web Environment with Static and Dynamic Page requests. International Conference on Internet and Web Applications and Services, February 23-25, 2006.

S. R. Chakravarthy, A. Krishnamoorthy and V. C. Joshua. Analysis of a Multi-server Retrial Queue with Search of Customers from the Orbit. Performance Evaluation, 63, 776-798, 2006.

J. R. Artalejo and S. R. Chakravarthy. Algorithmic Analysis of a Maximum Level Length in General-block Two-dimensional Markov Processes. Mathematical Problems in Engineering, Volume 2006 (2006), Article ID 53570, 15 pages.

J. R. Artalejo and S. R. Chakravarthy. Maximal Queue Length in a Busy Period of a MAP/M/c Retrial Queue. Applied Mathematics and Computation, 183, 1399-1409, 2006.

J. R. Artalejo and S. R. Chakravarthy. Algorithmic Analysis of a MAP/PH/1 Retrial Queue. TOP, 14, 293-332, 2006.

S. R. Chakravarthy. Analysis of a k-out-of-N System with Spares, Repairs, and a Probabilistic Rule. Journal of Applied Mathematics and Stochastic Analysis, Volume 2006 (2006), Article ID 39093, 23 pages.

S. R. Chakravarthy. A Multi-server Queueing Model with Markovian Arrivals and Multiple Thresholds. Asia-Pacific Journal of Operational Research, 24, 223-243, 2007.

S. R. Chakravarthy. A multi-server synchronous vacation model with thresholds and a probabilistic decision rule. European Journal of Operational Research, 182, 305-320, 2007.

J.R. Artalejo, Lopez-Herrero, and S. R. Chakravarthy. The busy period and the waiting time analysis of a MAP/M/c queue with finite retrial group. Stochastic Analysis and Applications, 25, 445-469, 2007.

S. R. Chakravarthy and S. R. Agnihothri. A Server Backup Model with Markovian Arrivals and Phase Type Services. European Journal of Operational Research, 184, 584-609, 2008.

S. R. Chakravarthy and A. G. Gomez-Corral. The influence of delivery times on repairable k-out-of-N systems with spares. Applied Mathematical Modeling, 33, 2368-2387, 2009.

S. R. Chakravarthy Analysis of a multi-server queue with Markovian arrivals and synchronous phase type vacations. Asia-Pacific Journal of Operational Research, 26, 85-113, 2009.

S. R. Chakravarthy. A disaster queue with Markovian arrivals and impatient customers. Applied Mathematics and Computation, 214, 48-59, 2009.

A. Krishnamoorthy, V. C. Narayanan, and S. R. Chakravarthy. The impact of priority generations in a multi-priority queueing system – A simulation approach. Proceedings of the 2009 Winter Simulation Conference, 1622-1633. Editors: M. D. Rossetti, R. R. Hill, B. Johansson, A. Dunkin, and R. G. Ingalls.

S. R. Chakravarthy, A. N. Dudin and V. I. Klimenok. A retrial queueing model with MAP arrivals, catastrophic failures with repairs, and customer impatience. Asia-Pacific Journal of Operational Research, 27, 727-752, 2010.

S. R. Chakravarthy Markovian Arrival Processes. Wiley Encyclopedia of Operations Research and Management Science. Published Online: 15 JUN 2010.

Catherine Brickner, Dennis Indrawan, Derrick Williams, and S. R. Chakravarthy. A stochastic model for a service system – A simulation approach. Proceedings of the 2010 Winter Simulation Conference, 1636-1647. Editors: B. Johansson, S. Jain, J. Montoya-Torres, J. Hugan, and E. Yücesan.

S. R. Chakravarthy. An inventory system with Markovian demands, phase type distributions for perishability and replenishment. OPSEARCH, 47, 266-283, 2010.

S. R. Chakravarthy. Analysis of a two-phase queueing model with MAP arrivals and fixed batch and individual services. J. Indian Society of Probability and Statistics, 12, 17-42, 2010.

S. R. Chakravarthy. Stochastic modeling in healthcare systems. Proceedings of the First International Conference on Simulation and Modeling Methodologies, Technologies and Applications, 109-115, 2011.

S. R. Chakravarthy. Stochastic modelling and simulation in healthcare system. Computational and Mathematical Modelling, 46-64, 2012, Editors: R. Nadarjan, R.S. Lekshmi, and G. Sai Sundara Krishnan.

S. R. Chakravarthy and Huang Qing. Analytical and Simulation Modeling of a Multi-server Queue with Markovian arrivals and Priority Services. Simulation Modelling Practice and Theory, 28, 12-26, 2012.

S. R. Chakravarthy. Maintenance of a deteriorating single server system with Markovian arrivals. European Journal of Operational Research, 222, 508-522, 2012.

S. R. Chakravarthy. Reliability, Heathcare, and Simulation. Simulation Modelling Practice and Theory, 29, 44-51, 2012.

A. Krishnamoorthy, V. Jacob, and S. R. Chakravarthy. On a customer induced interruption in a service system. Journal of Stochastic Analysis and Applications, 30, 949-962, 2012.

S. R. Chakravarthy. A stochastic model for a dynamic service facility with threshold and lead time. Proceedings of the Second International Conference on Stochastic Modelling and Simulation. Ed., S. Udayabaskaran, 3-22, 2012.

S. R. Chakravarthy and H. Karatza. Two-server Parallel System with Pure Sharing and Markovian Arrivals. Computers and Operations Research, 40, 510-519, 2013.

C. Sreenivasan, S. R. Chakravarthy and A. Krishnamoorthy. MAP/PH/1 queue with working vacations, vacation interruptions and N Policy. Applied Mathematical Modelling, 37, 3879-3893, 2013.

S. R. Chakravarthy Analysis of MAP/PH/c retrial queue with phase type retrials – Simulation approach. A. Dudin et al. (Eds.): BWWQT 2013, CCIS 356, 37-49, 2013.

S. R. Chakravarthy. Stochastic Modeling in Production, Manufacturing, and Service Systems. International Conference on Advances in Stochastic Modeling. Ed., V. Perumal, 15 pages, 2013.

S. R. Chakravarthy, M. Senthil Kumar and R. Arumuganathan. Preemptive Resume Priority Call Center Model with Two Classes of MAP Arrivals. Applied Mathematical Sciences, 7 (52), 2569 – 2589, 2013.

S. R. Chakravarthy and T. Ngniatedema. A Stochastic Model for a Delayed Product Customization. IAPQR TRANSACTIONS – Indian Association for Productivity, Quality & Reliability, 2013.

A. Krishnamoorthy, P. Pramod, and S. R. Chakravarthy. A note on characterizing service interruptions with phase type distribution. Stochastic Analysis and Applications, 31 (4), 671-683, 2013.

S. R. Chakravarthy. Analysis of MAP/PH_1,PH_2/1 queue with vacations and optional secondary services. Applied Mathematical Modeling, 37, 8886-8902, 2013.

S. R. Chakravarthy. Analysis of a multi-server queueing model with vacations and optional secondary services. Mathematica Applicanda, 41 (1), 127-151, 2013.

S. R. Chakravarthy. Making environment better with stochastic modeling. International Conference on Frontiers of Statistics and its Applications, Ed., Tirupathi Rao Padi, 175-179, Bonfring, 2013.

S. R. Chakravarthy. A multi-server queueing model with server consultations. European Journal of Operational Research, 233, 625-639, 2014.

S. R. Chakravarthy and Marcel F. Neuts. Analysis of a multi-server queueing model with MAP arrivals of regular customers and phase type arrivals of special customers. Simulation Modelling Practice and Theory, 43, 79-95, 2014.

A. Krishnamoorthy, P. Pramod, and S. R. Chakravarthy. Queues with interruptions: A survey. TOP, 22, 290-320, 2014. (DOI 10.1007/s11750-012-0256-6; Published online: 16 March 2012.

B. Dimitrov, L. Gawarecki, and S. R. Chakravarthy. Proceedings of Flint International Conference on Statistics – Celebration of International Year of Statistics, Kettering University, June 2014.

**Contact Information**

Email: scharkrav@kettering.edu

Phone: (810) 762-7906

Office: 1-700N AB