Article
Management
Walter J. Gutjahr
Summary: This paper extends two alternative approaches in inequity-averse optimization under uncertainty, from a static to a dynamic decision-making context. It shows that global optimization of strategies leads to time-consistent policies only in the ex-post case. The concepts are illustrated through a two-stage stochastic location-allocation problem from humanitarian logistics.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2021)
Article
Engineering, Manufacturing
Irem Sengul Orgut, Emmett J. Lodree
Summary: In the United States, food banks are crucial in reducing food insecurity by distributing donated food to those in need. One of their challenges is to distribute food donations equitably while minimizing waste. This paper presents a model to help food banks in effectively and fairly distributing perishable food donations and provides guidance on how to strategically control inequities.
PRODUCTION AND OPERATIONS MANAGEMENT
(2023)
Article
Economics
Douglas Alem, Aakil M. Caunhye, Alfredo Moreno
Summary: Modeling equity in humanitarian logistics is an important issue, and the Gini coefficient is a widely recognized measure of inequity. This paper derives the original Gini coefficient using the Lorenz curve and proposes new inequalities to improve the model. The study shows that alternative Gini definitions can lead to significantly different and less equitable decisions compared to the original Gini coefficient.
SOCIO-ECONOMIC PLANNING SCIENCES
(2022)
Article
Management
C. Filippi, G. Guastaroba, M. G. Speranza
Summary: This study addresses the problem of cost minimization and customer satisfaction in determining the location of facilities, proposing a fair conditional beta-mean measure for solving the cost minimization problem. The results show that this new model can play an important role in balancing costs and customer service, especially suitable for small and medium-sized instances.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2021)
Article
Operations Research & Management Science
Md Hafizul Islam, Julie Simmons Ivy
Summary: This study presents a mixed-integer programming model for efficient allocation of donated food from food banks, maintaining equity. Results show that sacrificing some equity can significantly improve effectiveness under certain cost conditions.
Article
Operations Research & Management Science
Arunachalam Narayanan, Nezih Altay
Summary: The COVID-19 pandemic disrupted global life, revealing challenges and opportunities for humanitarian organizations. Some organizations operate in long-term aid programs while also responding to disaster relief needs.
ANNALS OF OPERATIONS RESEARCH
(2021)
Article
Operations Research & Management Science
Farzad Avishan, Milad Elyasi, Ihsan Yanikoglu, Ali Ekici, O. Orsan Ozener
Summary: The management of humanitarian logistics operations is crucial and urgent after a disaster. This paper proposes an adjustable robust optimization approach for the related problems, considering uncertainties and limited resources. The proposed approach allows relief logistics teams to adjust their service decisions based on revealed information, resulting in more flexible and less conservative solutions. Heuristic algorithms are proposed to solve the computationally challenging optimization problems.
TRANSPORTATION SCIENCE
(2023)
Article
Public, Environmental & Occupational Health
M. Patrizia Santos, Jessica D. Brewer, Miguel A. Lopez, Valerie A. Paz-Soldan, M. Pia Chaparro
Summary: This study aimed to investigate the association between the gender of the head of the household, employment status of household members, and food insecurity in households with children in a low-income district of Lima, Peru. The study found that woman-headed households were more likely to experience food insecurity compared to man-headed households, and education also played a significant role in household food security.
Article
Engineering, Manufacturing
Tanzid Hasnain, Irem Sengul Orgut, Julie Simmons Ivy
Summary: This study focuses on the role of food banks in achieving food security and reducing inequalities, proposing a weighted multi-criteria optimization model and introducing an algorithm to analyze food bank preferences. The interactive nature of the algorithm is particularly significant for humanitarian organizations like food banks. Extensive numerical experiments were conducted to validate the efficiency of the algorithm.
PRODUCTION AND OPERATIONS MANAGEMENT
(2021)
Review
Nutrition & Dietetics
Sharonna Mossenson, Claire E. Pulker, Roslyn Giglia, Christina M. Pollard
Summary: This review synthesized the literature on policy approaches to nutrition-focused food banking in industrialized countries from 2000 to October 2021. The study identified six key themes, including the moral imperative to provide appropriate and nutritious food, the challenges of formalizing nutrition policies, the unpredictability of donated food, the impact of donor relationships on the provision of healthy foods, the importance of organizational capacity, and the need for a outcome metric based on nutritional quality.
Article
Transportation Science & Technology
Zabih Ghelichi, Monica Gentili, Pitu B. Mirchandani
Summary: The paper introduces a stochastic optimization-based approach to address the logistics for the timely delivery of aid packages to disaster-affected areas utilizing a fleet of drones when the set of demand points is unknown. The approach uses Chance Constrained Programming (CCP) and a space-time drone scheduling subproblem to select drone platform locations and minimize total disutility. An approximation method is developed to mitigate computational complexity. The proposed logistics system is evaluated through computational experiments and a case study, showing effective delivery of humanitarian aid packages.
TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES
(2022)
Article
Management
Okan Dukkanci, Achim Koberstein, Bahar Y. Kara
Summary: This study introduces a post-disaster delivery problem that utilizes drones under uncertainty, focusing on distributing essential relief items to victims gathered at assembly points after a disaster, specifically an earthquake. As roads may become impassable after an earthquake, drones serve as the primary mode of transportation. Considering the unpredictability of earthquake impacts, this study takes into account uncertainties in demand and road networks. Through stochastic programming and scenario decomposition algorithms, the objective is to minimize unsatisfied demand while meeting time constraints, range limitations, and capacity restrictions of the drones. A case study conducted in Istanbul, Turkey, evaluates the scenario decomposition algorithm's performance and analyzes the value of stochasticity and expected value of perfect information under various parametric settings. Sensitivity analyses are also performed by varying key problem parameters such as time constraints and drone capacities.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2023)
Article
Economics
Nistha Dubey, Ajinkya Tanksale
Summary: This study examines challenges and barriers faced by food banks in India, with a focus on policy, finance, infrastructure, human resources, planning coordination, knowledge, and uncertainty. Lack of planning and coordination was identified as the most significant barrier hindering the growth of food banks in India.
SOCIO-ECONOMIC PLANNING SCIENCES
(2022)
Article
Transportation Science & Technology
Faisal Alkaabneh, Karmel S. Shehadeh, Ali Diabat
Summary: Motivated by food distribution operations for non-profit organizations, this study focuses on a variant of the stochastic routing-allocation problem under demand uncertainty. Three stochastic mixed-integer programming (SMIP) models are proposed to optimize efficiency, equity, and both efficiency and equity simultaneously in food banks. An original matheuristic is developed based on adaptive large-scale neighborhood search to solve large-scale instances. Extensive numerical experiments using real-world data are conducted to evaluate the computational performance and derive insights relevant to food banks.
TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES
(2023)
Article
Operations Research & Management Science
Maliheh Khorsi, Seyed Kamal Chaharsooghi, Ali Husseinzadeh Kashan, Ali Bozorgi-Amiri
Summary: Vehicle routing models play a crucial role in disaster response by optimizing the allocation of relief resources to minimize negative consequences. This paper proposes a multi-period, multi-depot, multi-trip vehicle routing problem and solves it using a grouping metaheuristic algorithm. The performance of the solution method is evaluated through various test problems and statistical comparisons, and sensitivity analyses are conducted to validate the model.
ANNALS OF OPERATIONS RESEARCH
(2022)
Article
Engineering, Multidisciplinary
Ankit Bansal, Reha Uzsoy
Summary: CVRS is a primal heuristic for solving 0-1 Mixed Integer Linear Programming problems. It constructs a series of MILP subproblems and minimizes the sum of constraint violations to improve the objective function value. In testing, CVRS shows promising performance compared to other algorithms.
ENGINEERING OPTIMIZATION
(2021)
Article
Management
Karthick Gopalswamy, Reha Uzsoy
Summary: Several concave clearing functions used in production planning models can be reformulated as conic programs, which provide more accurate and efficient solutions for dual prices estimation compared to linear programming. The CP formulation outperforms LP solutions in terms of nervousness.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2021)
Article
Engineering, Manufacturing
Tanzid Hasnain, Irem Sengul Orgut, Julie Simmons Ivy
Summary: This study focuses on the role of food banks in achieving food security and reducing inequalities, proposing a weighted multi-criteria optimization model and introducing an algorithm to analyze food bank preferences. The interactive nature of the algorithm is particularly significant for humanitarian organizations like food banks. Extensive numerical experiments were conducted to validate the efficiency of the algorithm.
PRODUCTION AND OPERATIONS MANAGEMENT
(2021)
Editorial Material
Engineering, Manufacturing
Reha Uzsoy
IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING
(2022)
Article
Engineering, Industrial
Maaz Saleem Kapadia, Reha Uzsoy, Binil Starly, Donald P. Warsing
Summary: This study focuses on the order acceptance and scheduling problem in an additive manufacturing facility, using genetic algorithms to optimize the process and achieve significant profit improvements. The proposed approach outperforms statistically estimated bounds and provides high-quality solutions that meet all technological constraints.
INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH
(2022)
Article
Engineering, Industrial
Hubert Missbauer, Reha Uzsoy
Summary: Production planning and control systems are crucial for the competitiveness of manufacturing firms and their ability to leverage technological advancements. The research on order release function within PPC systems reveals a need for optimization models and further understanding of the dynamic response of production units. There are still unresolved research questions in this area that warrant further exploration.
INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH
(2022)
Article
Management
Foad Ghadimi, Tarik Aouam, Stefan Haeussler, Reha Uzsoy
Summary: This paper presents hierarchical models for coordinating order acceptance and release planning under load-dependent lead times. The models use detailed information at the item level and decompose the decision process into order acceptance and order release subproblems. The models address demand uncertainty through a rolling horizon framework and chance-constraints with safety stock.
EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
(2022)
Editorial Material
Engineering, Manufacturing
Reha Uzsoy
IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING
(2022)
Article
Operations Research & Management Science
Ankit Bansal, Osman Y. Ozaltin, Reha Uzsoy, Karl G. Kempf
Summary: Product transitions involve replacing current products in a company's supply chain with new products. Effective management of product transitions is crucial in high technology industries, requiring coordination among multiple product development units and a manufacturing unit serving a specific market.
NAVAL RESEARCH LOGISTICS
(2022)
Article
Engineering, Industrial
Foad Ghadimi, Tarik Aouam, Reha Uzsoy
Summary: This paper investigates the problem of safety stock placement in a supply chain with market selection decisions. By adopting the Guaranteed Service Approach, a nonlinear mixed-integer programming model is presented and solved using a successive piecewise linearization algorithm and a mixed-integer conic quadratic formulation. Computational experiments show that the successive piecewise linearization algorithm outperforms two state-of-the-art solvers, BARON and CPLEX. The paper also highlights that the integration of market selection and safety stock decisions provides the greatest benefit when capacity is limited and marginal revenue is relatively low.
Editorial Material
Engineering, Manufacturing
Reha Uzsoy
IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING
(2022)
Editorial Material
Engineering, Manufacturing
Reha Uzsoy
Summary: As the second issue of the year is published, the TSM team welcomes three new members and expresses gratitude to the departing members for their support and contributions.
IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING
(2023)
Article
Engineering, Manufacturing
Irem Sengul Orgut, Emmett J. Lodree
Summary: In the United States, food banks are crucial in reducing food insecurity by distributing donated food to those in need. One of their challenges is to distribute food donations equitably while minimizing waste. This paper presents a model to help food banks in effectively and fairly distributing perishable food donations and provides guidance on how to strategically control inequities.
PRODUCTION AND OPERATIONS MANAGEMENT
(2023)
Proceedings Paper
Computer Science, Theory & Methods
Carlos Leca, Karl Kempf, Reha Uzsoy
Summary: Continuous renewal of the product portfolio is crucial for semiconductor manufacturing firms, and coordination between different functional units is necessary. Decentralized models obtained through Lagrangian relaxation provide tight upper bounds on the optimal solution, but constructing near-optimal feasible solutions and achieving convergence can be challenging.
2022 WINTER SIMULATION CONFERENCE (WSC)
(2022)
Article
Computer Science, Interdisciplinary Applications
Rahman Khorramfar, Osman Y. Ozaltin, Karl G. Kempf, Reha Uzsoy
Summary: This study models the hierarchical and decentralized nature of product transitions using a mixed-integer bilevel program. The model consists of a manufacturing unit and an engineering unit as followers, and corporate management as a leader. The proposed solution method resolves the interdependency between the engineering and manufacturing units through the leader's coordination. Computational experiments demonstrate the effectiveness of the proposed approach in solving realistic instances.
INFORMS JOURNAL ON COMPUTING
(2022)
Article
Engineering, Industrial
Xubo Yue, Raed Al Kontar, Ana Maria Estrada Gomez
Summary: This article presents a federated data analytics approach for linear regression models, utilizing hierarchical modeling and information sharing to handle data distributed across different devices. It provides uncertainty quantification, variable selection, hypothesis testing, and fast adaptation to new data.
