Committee Chair

Weerasena, Lakmali

Committee Member

Ebiefung, Aniekan; Bandara, Damitha; Ma, Ziwei

Department

Dept. of Mathematics

College

College of Engineering and Computer Science

Publisher

University of Tennessee at Chattanooga

Place of Publication

Chattanooga (Tenn.)

Abstract

This dissertation investigates decision-making methods in Uncertain Discrete Multi-objective Optimization Problems (UDMOPs), where uncertainty arises in both objective function and constraint coefficients. The study pursues three main goals: (1) constructing sensitivity regions in the objective space to handle objective-wise uncertainty, (2) constructing sensitivity regions in the decision space to handle feasibility uncertainties, and (3) developing methods to sort, group, and prune uncertain solutions based on their similarity. Each goal proposes a method to explore uncertain solutions and quantify their level of uncertainty. Based on this, solutions are classified as low and high-risk solutions, according to the Decision-Maker (DM)'s preferences and risk tolerance. The proposed approaches employ stochastic optimization techniques to identify low and high-risk solutions, enabling risk-averse decision-making. Numerical experiments, including a real-world application, and benchmark comparisons, show that low or high-risk solutions under uncertainty can outperform the efficient solutions from deterministic model. Overall, the methods provide a more consistent and informative decision support system for DMs under uncertainty.

Acknowledgments

I would like to thank the Department of Mathematics and the Graduate School at UTC for providing me with the opportunity to pursue my Ph.D. I sincerely appreciate the support from the Departments of Mathematics and Computer Science, as well as the National Science Foundation (LEAPS-MPS) under Grant #2137622, for funding my assistantship. I am especially thankful to my advisor, Dr. Lakmali Weerasena, for her invaluable knowledge, encouragement, and continuous guidance throughout this research. I am grateful to mycommittee members, Dr. Aniekan Ebiefung, Dr. Damitha Bandara, and Dr. Ziwei Ma, for their insightful feedback and support. In addition, I would like to thank all my teachers, and especially to Dr. W.B. Daundasekera, Dr. Christopher L. Cox and Dr. Francesco Barioli for their contributions and encouragement during this journey. Last but not least, I extend my heartfelt appreciation to my family, my late father, K. G. B. Aththanayake, whose greatest wish was to see this accomplishment; my mother Anula Ranaraja; my siblings Janaka and Nadeesha; my husband Rukman; and my beloved son Sasiru, who stood by me through every challenge. Their unwavering love, support and belief in me have been my greatest source of strength and motivation.

Degree

Ph. D.; A dissertation submitted to the faculty of the University of Tennessee at Chattanooga in partial fulfillment of the requirements of the degree of Doctor of Philosophy.

Date

8-2025

Subject

Decision making--Mathematical models; Sensitivity theory (Mathematics); Stochastic programming; Uncertainty--Mathematical models

Keyword

Decision-Making; Multi-objective Optimization; Pruning; Sensitivity Region; Uncertainty

Document Type

Doctoral dissertations

DCMI Type

Text

Extent

xv, 214 leaves

Language

English

Rights

http://rightsstatements.org/vocab/InC/1.0/

License

http://creativecommons.org/licenses/by/4.0/

Date Available

8-31-2026

Available for download on Monday, August 31, 2026

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