My research interests are mainly in continuous optimization. More specifically, I am interested in the theoretical aspects, design, analysis, and implementation of algorithms, and applications. I earned my Ph.D. under the supervision of Michael J. Todd at the School of Operations Research and Information Engineering at Cornell University. Here is a broad list of my research interests:

- Mathematical optimization
- Convex optimization
- Continuous optimization
- Design and analysis of algorithms
- Applied optimization

RESEARCH GRANTS and PROJECTS

Past

- Role: Principal Investigator, Type of Grant: National Science Foundation Faculty Early Career Development (CAREER) Award, Funding Agency: National Science Foundation, Title: CAREER: A Unifying Interior-Point Approach to Sensitivity Analysis and Reoptimization in Conic Programming, Amount: USD 400,000, Duration: June 1, 2003 -- May 31, 2008 (terminated in August 2006 due to relocation), Project Number: DMI0237415. (Abstract)
- Role: Principal Investigator, Type of Grant: Strategic Partnership for Industrial Resurgence (SPIR), Funding Agency: ADP Investor Communications Services, Title: SPIR - Algorithmic Aspects of Booklet Bundling, Amount: USD 18,593, Duration: July 15, 2004 -- July 15, 2005. (Co-PIs: Joseph S. B. Mitchell and Esther M. Arkin)
- Role: Principal Investigator, Type of Grant: Bilkent University Faculty Research Development Grant, Funding Agency: Bilkent University, Title: Investigations in Geometric Optimization, Amount: USD 1,500, Duration: January 1, 2007 -- December 31, 2007.
- Role: Principal Investigator, Type of Grant: TUBITAK (Turkish Scientific and Technological Research Council) 1002, Funding Agency: TUBITAK, Title: Development of Specific and Efficient Algorithms for Large-Scale Geometric Optimization Problem,Amount: 20,250 TRY, Duration: October 1, 2007 -- October 1, 2008,Project Number: 107M411.
- Role: Co-Investigator, Type of Grant: Partnership with Industry, Funding Agency: Platform ARGE, Title: Optimization of Spare Parts Depot and Spare Parts Distribution System at TOFAS A.S., Amount: 80,000 TRY, Duration: November 1, 2007 -- August 31, 2008. (PI: Barbaros Tansel)
- Role: Principal Investigator, Type of Grant: TUBITAK (Turkish Scientific and Technological Research Council) 1010 EVRENA, Funding Agency: TUBITAK, Title: A Comprehensive Proposal Evaluation and Selection System, Amount: 212,180 TRY, Duration: August 1, 2009 -- February 1, 2012,Project Number: 109M149. (Other Participants: Cevdet Aykanat and Yavuz Oruc)
- Role: Co-Investigator, Type of Grant: TUBITAK (Turkish Scientific and Technological Research Council) 1001, Funding Agency: TUBITAK, Title: Multi-Objective Optimization Based Solution Methods for Planning and Operational Problems of Wireless Mesh Networks, Amount: 111,840 TRY, Duration: October 1, 2010 -- October 1, 2012, Project Number: 110M312. (PI: Kagan Gokbayrak)
- Role: Co-Investigator, Type of Grant: TUBITAK (Turkish Scientific and Technological Research Council) 1001, Funding Agency: TUBITAK, Title: Optimization of Production-Emission and Carbon Allowance Trading Processes Under the Carbon Trade Mechanism and Statistical Analysis of Carbon Market Data, Amount: 135,295 TRY, Duration: September 15, 2010 -- September 15, 2012, Project Number: 110M307. (PI: Ulku Gurler, Other Co-Investigators: Emre Berk and Deniz Yenigun)
- Role: Co-Investigator, Type of Grant: TUBITAK (Turkish Scientific and Technological Research Council) 1001, Funding Agency: TUBITAK, Title: Advanced Multi-Objective Optimization Techniques for Simultaneous Berth Allocation and Crane Scheduling Problem under Uncertainty, Amount: 118,610 TRY, Duration: June 1, 2013 -- June 1, 2015, Project Number: 112M865. (PI: Deniz Ozdemir)
- Role: Co-Principal Investigator, Type of Grant: IBM Open Collaborative Research (OCR) Award, Funding Agency: IBM, Title: Proactive Transportation Plan Management, Amount: USD 30,000, Duration: March 1, 2013 -- March 1, 2015. (PI: Metin Turkay)
- Role: Principal Investigator, Type of Grant: TUBITAK (Turkish Scientific and Technological Research Council) 1001, Funding Agency: TUBITAK, Title: Copositive Optimization Based Solution Approaches for NP-Hard Optimization Problems, Amount: 196,780 TRY, Duration: June 1, 2013 -- December 1, 2015, Project Number: 112M870.

**PhD
Thesis**

- An interior-point perspective on sensitivity analysis in linear programming and semidefinite programming, Ph.D. thesis submitted to Cornell University. (2001) pdf

- Sensitivity analysis in linear programming and semidefinite programming using interior-point methods, E. Alper Yildirim and Michael J. Todd. Mathematical Programming, 90 (2) pp. 229-261 (2001). DOI
- An interior-point approach to sensitivity analysis in degenerate linear programs, E. Alper Yildirim and Michael J. Todd. SIAM Journal on Optimization, 12 (3) pp. 692-714 (2002). DOI
- Warm-start strategies in interior-point methods for linear programming, E. Alper Yildirim and Stephen J. Wright. SIAM Journal on Optimization, 12 (3) pp. 782-810 (2002). DOI
- An interior-point perspective on sensitivity analysis in semidefinite programming, E. Alper Yildirim. Mathematics of Operations Research, 28 (4) pp. 649-676 (2003). DOI
- Approximate minimum enclosing balls in high dimensions using core-sets, Piyush Kumar, Joseph S. B. Mitchell, and E. Alper Yildirim, The ACM Journal of Experimental Algorithmics, Vol. 8, Article 1 (2003). (Special issue devoted to selected papers from the Fifth Workshop on Algorithm Engineering and Experiments (ALENEX03)) DOI
- Unifying optimal partition approach to sensitivity analysis in conic optimization, E. Alper Yildirim. Journal of Optimization Theory and Applications, 122 (2) pp. 405-423 (2004). DOI
- Minimum volume enclosing ellipsoids and core sets, Piyush Kumar and E. Alper Yildirim. Journal of Optimization Theory and Applications, 126 (1) pp. 1-21 (2005). DOI Erratum
- On extracting maximum stable sets in perfect graphs using Lovasz's theta function, E. Alper Yildirim and Xiaofei Fan-Orzechowski. Computational Optimization and Applications, 33 (2-3) pp. 229-247 (2006). DOI
- On the minimum volume covering ellipsoid of ellipsoids, E. Alper Yildirim. SIAM Journal on Optimization, 17 (3) pp. 621-641 (2006). DOI (Winner of the 2006 INFORMS Optimization Society Young Researcher Prize)
- On Khachiyan's algorithm for the computation of minimum-volume enclosing ellipsoids, Michael J. Todd and E. Alper Yildirim. Discrete and Applied Mathematics, 155 (13) pp. 1731-1744 (2007). DOI
- Computing minimum volume enclosing axis-aligned ellipsoids, Piyush Kumar and E. Alper Yildirim. Journal of Optimization Theory and Applications, 136 (2) pp. 211-228 (2008). DOI
- Implementation of warm-start strategies in interior-point methods for linear programming in fixed dimension, Elizabeth John and E. Alper Yildirim. Computational Optimization and Applications, 41 (2) pp. 151 - 183 (2008). DOI
- Two algorithms for the minimum enclosing ball problem, E. Alper Yildirim. SIAM Journal on Optimization, 19 (3) pp. 1368-1391 (2008). DOI
- Identification and elimination of interior points for the minimum enclosing ball problem, S. Damla Ahipasaoglu and E. Alper Yildirim. SIAM Journal on Optimization, 19 (3) pp. 1392-1396 (2008). DOI
- An algorithm and a core set result for the weighted Euclidean one-center problem, Piyush Kumar and E. Alper Yildirim. INFORMS Journal on Computing, 21 (4) pp. 614-629 (2009). DOI
- A simpler characterization of a spectral lower bound on the clique number, E. Alper Yildirim. Mathematical Methods of Operations Research, 71 (2) pp. 267-281 (2010). DOI
- A linearly convergent linear-time first-order algorithm for support vector classification with a core set result, Piyush Kumar and E. Alper Yildirim. INFORMS Journal on Computing, 23 (3) pp. 377-391 (2011). DOI
- On the accuracy of uniform polyhedral approximations of the copositive cone, E. Alper Yildirim. Optimization Methods and Software, 27 (1) pp. 155-173 (2012). DOI
- A hierarchical solution approach for a multicommodity distribution problem under a special cost structure, Esra Koca and E. Alper Yildirim. Computers and Operations Research, 39 (11) pp. 2612-2624 (2012). DOI
- Joint gateway selection, transmission slot assignment, routing and power control for wireless mesh networks, Kagan Gokbayrak and E. Alper Yildirim. Computers and Operations Research, 40 (7) pp. 1671-1679 (2013). DOI
- Rounding
on the standard simplex: Regular grids for global optimization,
Immanuel
M. Bomze, Stefan Gollowitzer, and E.
Alper Yildirim. Journal
of Global Optimization, 59 (2-3) pp.
**243-258**(2014). DOI (Winner of the Journal of Global Optimization Best Paper Award for a paper published in 2014) - Numerical optimization of
eigenvalues of Hermitian matrix functions, Emre Mengi, E.
Alper Yildirim, and
Mustafa Kilic. SIAM
Journal on Matrix Analysis and Applications, 35 (2) pp.
**699-724**(2014). DOI - Analysis
of copositive optimization based linear programming bounds on
standard quadratic optimization, Gizem Sagol and E. Alper Yildirim.
**Journal of Global Optimization**, 63 (1) pp.**37-59**(2015). DOI - Optimality conditions in nonconvex and nonsmooth optimization revisited, Refail Kasimbeyli and E. Alper Yildirim. Pure and Applied Functional Analysis, to appear.
- Exact and heuristic approaches based on noninterfering transmissions for joint gateway selection, transmission slot allocation, routing and power control for wireless mesh networks, Kagan Gokbayrak and E. Alper Yildirim. Computers and Operations Research, to appear.
- Inner approximations of completely positive reformulations of mixed binary quadratic optimization problems: A unified analysis, E. Alper Yildirim. Optimization Methods and Software, to appear. PDF

- Computing core-sets and approximate smallest enclosing hyperspheres in high dimensions, Piyush Kumar, Joseph S. B. Mitchell, and E. Alper Yildirim. Proceedings of the Fifth Workshop on Algorithm Engineering and Experiments (ALENEX03), pp. 45 - 55. (2003)
- Joint routing, gateway selection, scheduling and power management optimization in wireless mesh networks, Kagan Gokbayrak, Onur Uzunlar, and E. Alper Yildirim. Proceedings of the Industrial and Systems Engineering Research Conference (ISERC 2012). (2012)

**Ph.D.
Students**

**Past**

- Elizabeth John, Ph.D. in Applied Mathematics and Statistics, Stony Brook University, August 2005. Thesis Title: An Implementation of Warm-Start Strategies in Interior-Point Methods for Linear Programming.
- Xiaofei Fan-Orzechowski, Ph.D. in Applied Mathematics and Statistics, Stony Brook University, December 2005. Thesis Title: Applications of Lovasz's Theta and Lagrangian Functions to Certain Deterministic and Stochastic Optimization Problems. (Co-advised with Eugene Feinberg, Stony Brook University)
- Gizem Sagol, Ph.D. in Industrial Engineering and Operations Management, Koc University, August 2016. Thesis Title: On Polyhedral Approximations of Copositive Formulations of Certain Quadratic Optimization Problems.

Current

- Yakup Gorkem Gokmen, Ph.D. Student in Industrial Engineering and Operations Management, Koc University. (Thesis Title: TBD)
- Oguz Can Binatli, Ph.D. Student in Industrial Engineering and Operations Management, Koc University. (Thesis Title: TBD)
- Nermin Elif Kurt, Ph.D. Student in Industrial Engineering and Operations Management, Koc University. (Thesis Title: TBD) (Co-advised with Lerzan Ormeci, Koc University)

M.S. Theses

- Esra Koca, M.S. in Industrial Engineering, Bilkent University, July 2010. Thesis Title: A Two-Stage Solution Approach to Spare Parts Distribution under a Special Cost Structure.
- Utku Guruscu, M.S. in Industrial Engineering, Bilkent University, July 2010. Thesis Title: Implementation of a Specialized Algorithm for Clustering Using Minimum Enclosing Balls.
- Ahmed Burak Pac, M.S. in Industrial Engineering, Bilkent University, September 2010. Thesis Title: Row Generation Techniques for Approximate Solution of Linear Programming Problems.
- Selva Selfun, M.S. in Industrial Engineering, Bilkent University, July 2011. Thesis Title: Outer Approximation Algorithms for the Congested p-Median Problem. (Co-advised with Hande Yaman, Bilkent University)
- Onur Uzunlar, M.S. in Industrial Engineering, Bilkent University, July 2011. Thesis Title: Joint Routing, Gateway Selection, Scheduling, and Power Management Optimization in Wireless Mesh Networks. (Co-advised with Kagan Gokbayrak, Bilkent University)
- Senem Sancar, M.S. in
Industrial Engineering, Koc University, July 2014. Thesis
Title:
*Simultaneous Berth Allocation and Quay Crane Assignment Problem*. (Co-advised with Deniz Ozdemir, Yasar University) **Ali Yesilcimen**, M.S. in Industrial Engineering, Koc University, February 2015. Thesis Title:*Alternative Optimization Models for Reviewer Allocation in Peer Review Systems*.**Ali Hassanzadeh Kalshani**, M.S. in Industrial Engineering, Koc University, July 2015. Thesis Title:*Optimization Based Heuristics for the Graph Partitioning Problem*.**Ozge Soyogul**, M.S. in Industrial Engineering, Koc University, February 2016. Thesis Title: A Simulation-Optimization Approach to the Storage Location Assignment Problem: A Case Study of a Distribution Warehouse in Automotive Manufacturing.

Current

- Ismail Ozan Sert, M.S. Student in Industrial Engineering, Koc University. (Thesis Title: TBD) (Co-advised with Metin Turkay, Koc University)

- Optimization Online. A repository of papers in optimization.
- Mathematical Optimization Society
- SIAM. Society of Industrial and Applied Mathematics.
- SIAM Activity Group on Optimization
- INFORMS. Institute for Operations Research and Management Sciences.
- INFORMS Optimization Society
- Mathematical Programming Glossary
- School of Operations Research and Information Engineering, Cornell University.

Last updated on October 7, 2016. Back to my homepage.