Southampton Management School

Tolga Bektas

BSc MSc PhD FHEA

Primary position:
Senior Lecturer in Management Sciences

Tolga Bektas is a Senior Lecturer in Management Science. Tolga has a PhD in Industrial Engineering from Bilkent University in 2005. His dissertation titled Discrete Location Models for Content Distribution received an Honorable Mention from the INFORMS Telecommunications Section in April 2006. Prior to joining the University of Southampton in August 2007, he worked as a postdoctoral research fellow at the University of Alberta, CIRRELT and University of Montreal in Quebec.

Tolga is the programme director of the MSc in Business Analytics and Management Sciences at the School of Management.  Limited funding is available for this programme open to UK/EU full-time students and is offered on a competitive basis.

Dr Tolga Bektas's photo

The University of Southampton's electronic library (e-prints)

Article

Bektas, T. (2012) Formulations and Benders decomposition algorithms for multidepot salesmen problems with load balancing. European Journal of Operational Research, 216, 83-93. (doi:10.1016/j.ejor.2011.07.020)
Paksoy, T., Bektas, T. and Ozceylan, E. (2011) Operational and environmental performance measures in a multi-product closed-loop supply chain. Transportation Research Part E: Logistics and Transportation Review, 47, (4), 532-546. (doi:10.1016/j.tre.2010.12.001)
Demir, E., Bektas, T. and Laporte, G. (2011) A comparative analysis of several vehicle emission models for freight transportation. Transportation Research Part D: Transport and Environment, 16, (5), 347-357. (doi:10.1016/j.trd.2011.01.011)
Bektas, T., Erdogan, G. and Ropke, S. (2011) Formulations and branch-and-cut algorithms for the generalized vehicle routing problem. Transportation Science, 45, (3), 299-316. (doi:10.1287/trsc.1100.0352)
Bektas, T. and Laporte, G. (2011) The pollution-routing problem. Transportation Research Part B: Methodological, 45, (8), 1232-1250. (doi:10.1016/j.trb.2011.02.004)
Bauer, J., Bektas, T. and Crainic, T.G. (2010) Minimizing greenhouse gas emissions in intermodal freight transport: An application to rail service design. Journal of the Operational Research Society, 61, 530-542. (doi:10.1057/jors.2009.102)
Bektas, T., Chouman, M. and Crainic, T.G. (2010) Lagrangean-based decomposition algorithms for multicommodity network design problems with penalized constraints. Networks, 55, (3), 171-180. (doi:10.1002/net.20362)
Ahkioon, S., Bulgak, A.A. and Bektas, T. (2009) A comprehensive mathematical modeling approach to the design of cellular manufacturing systems integrating production planning and system reconfiguration. European Journal of Operational Research, 192, 414-428. (doi:10.1016/j.ejor.2007.09.023)
Ahkioon, S., Bulgak, A.A. and Bektas, T. (2009) Cellular manufacturing systems design with routing flexibility, machine procurement, production planning and dynamic system reconfiguration. International Journal of Production Research, 47, (6), 1573-1600. (doi:10.1080/00207540701581809)
Bektas, T., Cordeau, J-F., Erkut, E. and Laporte, G. (2008) Exact algorithms for the joint object placement and request routing problem in content distribution networks. Computers & Operations Research, 35, (12), 3860-3884. (doi:10.1016/j.cor.2007.02.005)
Bektas, T. and Bulgak, A.A. (2008) Lagrangean-based solution approaches for the generalized problem of locating capacitated warehouses. International Transactions in Operational Research, 15, (1), 67-85. (doi:10.1111/j.1475-3995.2007.00616.x)
Bektas, T., Crainic, T.G. and Morency, V. (2008) Improving performance of rail yards through dynamic reassignments of empty cars. Transportation Research Part C: Emerging Technologies, 17, 259-273. (doi:10.1016/j.trc.2008.11.003)
Bektas, T., Cordeau, J-F., Erkut, E. and Laporte, G. (2008) A two-level simulated annealing algorithm for efficient dissemination of electronic content. Journal of the Operational Research Society., 59, 1557-1567. (doi:10.1057/palgrave.jors.2602490)
Dubuc, G., Bektas, T., Cordeau, J-F. and Laporte, G. (2008) Une heuristique de recherche avec tabous pour la conception de reseaux de distribution de contenu electronique. Information Systems and Operational Research, 45, (3), 175-185. (doi:10.3138/infor.45.3.175)
Bektas, T. and Elmastas, S. (2007) Solving school bus routing problems through integer programming. Journal of the Operational Research Society, 58, (12), 1599-1604. (doi:10.1057/palgrave.jors.2602305)
Bektas, T., Oguz, O. and Ouveysi, I. (2007) A Lagrangean relaxation and decomposition algorithm for the video placement and routing problem. European Journal of Operational Research, 182, (1), 455-465. (doi:10.1016/j.ejor.2006.07.031)
Bektas, T., Oguz, O. and Ouveysi, I. (2007) Designing cost-effective content distribution networks. Computers & Operations Research, 34, (8), 2436-2449. (doi:10.1016/j.cor.2005.09.013)
Bektas, T. and Oğuz, O. (2007) On separating cover inequalities for the multidimensional knapsack problem. Computers & Operations Research, 34, (6), 1771-1776. (doi:10.1016/j.cor.2005.05.032)
Kara, I. and Bektas, T. (2006) Integer linear programming formulations of multiple salesman problems and its variations. European Journal of Operational Research, 174, (3), 1449-1458. (doi:10.1016/j.ejor.2005.03.008)
Bektas, T. (2006) The multiple traveling salesman problem: an overview of formulations and solution procedures. Omega: The International Journal of Management Science, 34, (3), 209-219. (doi:10.1016/j.omega.2004.10.004)
Dengiz, B., Bektas, T. and Ultanir, A.E. (2006) Simulation optimisation based DSS application: a diamond tool production line in industry. Simulation Modelling Practice & Theory, 14, (3), 296-312. (doi:10.1016/j.simpat.2005.07.001)
Bektas, T., Oguz, O. and Ouveysi, I. (2006) A novel optimization algorithm for video placement and routing. IEEE Communications Letters, 10, (2), 114-116. (doi:10.1109/LCOMM.2006.02007)
Kara, I., Laporte, G. and Bektas, T. (2004) A note on the lifted Miller-Tucker-Zemlin subtour elimination constraints for the capacitated vehicle routing problem. European Journal of Operational Research, 158, (3), 793-795. (doi:10.1016/S0377-2217(03)00377-1)

Book Section

Juan, A., Faulin, J., Bektas, T. and Grasman, S.E. (2011) A hybrid algorithm based on Monte-Carlo simulation for the vehicle routing problem with route length restrictions. In, Montoya-Torres, Jairo R., Juan, Angel A., Huatuco, Luisa Huaccho, Faulin, Javier and Rodriguez-Verjan, Gloria. L. (eds.) Hybrid Algorithms for Service, Computing and Manufacturing Systems: Routing and Scheduling Solutions. Hershey, US, IGI Global, 122-135. (doi:10.4018/978-1-61350-086-6)
Bektas, Tolga and Ouveysi, Iradj (2008) Mathematical models for resource management and allocation in content delivery networks. In, Buyya, Rajkumar, Pathan, Mukkadim and Vakali, Athena (eds.) Content Delivery Networks. , Springer, 225-250. (Lecture Notes in Electrical Engineering, 9).
Bektas, T. and Crainic, T.G. (2007) A brief review of intermodal transportation. In, Taylor, G. Don (ed.) Logistics Engineering Handbook. Boca Raton, CRC Press.
Özkök, Onur, Pakdil, Fatma, Çamlıca, Fahri Buğra, Bektas, Tolga and Kara, İmdat (2005) A pathway for process improvement activities in a production environment: a case study in a rework department. In, Can der Aalst, W.M.P. (ed.) Business Process Management. 3rd International Conference, BPM 2005 Berlin, Germay, Springer-Verlag, 344-353. (Lecture Notes in Computer Science 3649). (doi:10.1007/11538394_23)
Kara, Imdat and Bektas, Tolga (2005) Minimal load constrained vehicle routing problems. In, Sunderam, V. (ed.) Computational Science: ICCS 2005. 5th International Conference on Computer Science - ICCS 2005 Berlin, Germay, Springer-Verlag, 188-195. (Lecture Notes in Computer Science, 3514 3514). (doi:10.1007/11428831_24)

Conference or Workshop Item

Bektas, T., Crainic, T.G. and Gendron, B. (2009) Lagrangean decomposition for the fixed charge multicommodity network design problem. In, International Network Optimization Conference, Pisa, Italy, 26 - 29 Apr 2009.
Bektas, T., Erdogan, G. and Ropke, S. (2008) Formulations and branch-and-cut algorithms for the generalized vehicle routing problem. In, OR50 Annual Conference, York, UK, 09 - 11 Sep 2008. York, UK, The OR Society.
Kioon, Steve Ah, Bulgak, Akif Asil and Bektas, Tolga (2008) An ILP-embedded Tabu Search heuristic for the design of integrated cellular manufacturing systems with production planning and dynamic system reconfiguration. In, International Conference on Metaheuristics and Nature Inspired Computing (META'08), Hammamet, Tunisia, 29 - 31 Oct 2008. Hammamet, Tunisia.,
Bektas, Tolga, Crainic, Teodor Gabriel and Gendron, Bernard (2007) Lagrangean decomposition for the multicommodity capacitated network design problem. In, Optimization Days 2007, Montreal, Canada, 07 - 09 May 2007.
Bektas, T. and Crainic, T.G. (2007) Relaxations and solution methods for a class of nonlinear multicommodity network design formulations. In, Optimization Days, Montreal, Canada, 07 - 09 May 2007. (Submitted)
Bektas, Tolga and Crainic, Teodor Gabriel (2007) Decomposition algorithms for multicommodity network design problems with penalized constraints. In, Proceedings of INOC 2007, Spa, Belgium, 22 - 25 Apr 2007.
Bektas, T., Cainic, T.G. and Morency, V. (2007) Improving performance of rail yards through dynamic reassignments of empty cars. In, Optimization Days, Montreal, Canada, 07 - 09 May 2007.
Bektas, Tolga and Crainic, Teodor Gabriel (2006) Dynamic empty car management in railyards. In, INFORMS Annual Meeting, Pittsburgh, USA, 508 Nov 2006. Pittsburgh: USA,
Bektas, Tolga, Safaei, Farzad, Ouveysi, Iradj and Oguz, Osman (2006) Dissemination of dynamic multimedia content in networked virtual environments. In, Proceedings of Multicomm 06, Istanbul, Turkey, 11 Jun 2006. Institute of Electrical and Electronics Engineers, 31-36.
Bektas, T., Cordeau, J.-F., Erkut, E. and Laporte, G. (2006) Simultaneous object placement and request routing in content distribution networks. In, The 8th INFORMS Telecommunications Conference, Dallas, USA, Dallas: TX: USA,
Bektas, T., Cordeau, J.F., Erkut, E. and Laporte, G. (2006) Simultaneous object placement and request routing in context distribution networks. In, 8th INFORMS Telecommunications Conference, Dallas, USA, 30 Mar - 02 Apr 2006. (Submitted)
Bektas, T. and Oguz, O. (2005) Discrete location models for internet content distribution. In, Optimisation 2004, Lisbon, Portugal, 25 - 28 Jul 2004.
Bektas, T. and Kara, I. (2003) On the subtour elimination constraints of the multiple traveling salesman problem. In, Young OR 13, Bath, UK, 01 - 03 Apr 2003.
Kara, I. and Bektas, T. (2000) Derivation of the Miller-Tucker-Zemlin subtour elimination constraints of the traveling salesman problem. In, International Symposium on Combinatorial Optimisation (CO2000), London, UK, 12 - 14 Jul 2000. Greenwich: London: UK,

Monograph

Nock, A., Bektas, T., Ojiako, U. and Chipulu, M. (2010) The practical use of feasibility decision assessment models. Southampton, University of Southampton (Discussion Papers in Centre for Operational Research, Management Science and Information Systems; WorkingPaperSeries --> Centre for Operational Research, Management Science and Information Systems, CORMSIS-10-04)
Pugh, J. and Bektas, T. (2009) Bridging the gap between policies, theories and practices of environmentally friendly freight transportation. Southampton, UK, University of Southampton (Discussion Papers in Centre for Operational Research, Management Science and Information Systems,(CORMSIS-09-16))
Bektas, T., Chouman, M. and Crainic, T.G. (2008) Lagrangean-based decomposition algorithms for multicommodity network design problems with penalized constraints. , University of Southampton (Discussion Papers in Centre for Operational Research, Management Science and Information Systems,(CORMSIS-08-06))
Ahkioon, S., Bulgak, A.A. and Bektas, T. (2008) An ILP-embedded Tabu Search heuristic for the design of integrated cellular manfacturing systems with production planning and dynamic system reconfiguration.
Bektas, T., Crainic, T.G. and Gendron, B. (2008) Lagrangean decomposition for the fixed charge multicommodity network design problem. Southampton, UK, University of Southampton (Discussion Papers in Centre for Operational Research, Management Science and Information Systems,(CORMSIS-08-17))
Bektas, T., Chouman, M. and Crainic, T.G. (2007) Decomposition algorithms for a class of nonlinear multicommodity network design problems. , University of Southampton (Discussion Papers in Centre for Operational Research, Management Science and Information Systems,(CORMSIS-08-06))
Bektas, T. and Gouveia, L. (2007) Further extensions of the Miller-Tucker-Zemlin constraints of the asymmetric traveling salesman problem. , University of Southampton
 

Research Interests

Mathematical modelling and optimisation of a variety of problems in distribution logistics, system (strategic) design of logistics networks; telecommunications network design; warehouse location; service network design in intermodal transportation; operational level planning in transport, vehicle routing and scheduling, railyard management; reducing the environmental hazards of freight logistics and transportation activities, in particular reduction of CO2 emissions.

If you are interested in working with me at a PhD level in any of the areas linked to above, you can apply to our PhD programme where we have a number of studentships available. Alternatively, if you wish to self-fund your Ph.D. studies, then e-mail me your C.V. along with a research proposal.

Primary research group:  CORMSIS: Centre for Operational Research, Management Science and Information Systems

Affiliate research group:  Centre for Risk Research

Research projects

Reducing Greenhouse Gas Emissions

As the environmental impacts of freight transport increase, the need to mitigate these is paramount. A way to achieve this is through better planning methods that explicitly take into account emissions.

The LANCS Initiative in Foundational Operational Research (S&I bid) - Management

Developing world-leading work in the field of Operational Research (OR).

Work in progress


Journal Editorship
Co-editor of OR Insight, a journal of the OR Society. If you are interested in submitting a manuscript to this journal, visit Palgrave Macmillan for instructions.

Member of the Editorial Board of Computers & Operations Research.

Guest editor, together with Prof Gilbert Laporte of HEC Montreal, a Special Issue of Journal of the Operational Research Society on Transportation, Logistics and the Environment (2010).

Research Projects and Funding
Co-investigator, "Overcoming Capacity Constraints - A Simulation Integrated with Optimisation for Nodes (OCCASION)" (October 2010–October 2012). A £400,000 (fEC) project supported by the Engineering and Physical Sciences Research Council (EPSRC) and the Rail Safety and Standards Board (RSSB). Visit the EPSRC website more details.

Co-leader, "Reducing greenhouse gas emissions in road-based freight transport through mathematical modelling" (June 2010–June 2011). With a financial support of £1,300 by the British Council's Partnership Programme in Science - United Kingdom and the Netherlands. In partnership with Dr Tom Van Woensel from the Technische Universiteit Eindhoven.

Principal investigator, "Mathematical models and optimisation algorithms for sustainable logistics and transportation planning problems" (July 2010–July 2011). With a financial support of £1,200 by the Santander Abbey Internationalisation Fund.

Principal investigator, "Design of intermodal transportation networks with environmental considerations" (June 2008–March 2009). With a financial support of £24,000 by University of Southampton's Annual "Adventure in Research" Research Grant and £4,980 by the Internationalisation Fund. Carried out in collaboration with the NSERC Industrial Research Chair on Logistics Management held by Professor Teodor G Crainic at the University of Quebec in Montreal (UQAM), Canada.

Involved with the LANCS-Initiative, in particular in the Transport & Logistics and Optimisation clusters.

I have to date been involved in teaching on the following modules at the School of Management:
MANG2006: Principles and Practice of Management Science (UG)

MANG2021: Operations Management (UG)

MANG3048: Management Science for Engineers (UG)

MANG3034: Project Management (UG)

MANG6192: Decision Modelling and Analysis (MBA)

MANG7001: Research Methods (PhD)

I am a recipient of the Vice-Chancellor's Teaching Award in 2010.

Dr Tolga Bektas
Southampton Management School
University of Southampton
Southampton
SO17 1BJ, UK.

Phone +44 (0)23 8059 8969
Fax +44 (0)23 8059 3844
E-mail T.Bektas@soton.ac.uk

Room Number: 2/6015