The Humanitarian Pickup and Distribution Problem

Eisenhandler O. and Tzur M. (2019a). “The Humanitarian Pickup and Distribution Problem”. Operations Research, 67(1), 10-32.

Food rescue, i.e., the collection of perishable products from food suppliers who are willing to make donations and their distribution to welfare agencies that serve individuals in need, has become increasingly widespread in recent years as a result of economic crises, but also because of the benefit of donors from the food industry. The problem we study in this paper focuses on the logistic challenges of a food bank that on a daily basis uses vehicles of limited capacity to distribute food collected from suppliers in the food industry to welfare agencies, under an imposed maximal traveling time. We model this problem as a routing – resource allocation problem, with the aim of maintaining equitable allocations to the different agencies, while delivering overall as much as possible. We introduce an innovative objective function that satisfies desired properties of the allocation, that is easy to compute and implement within a mathematical formulation, and that balances effectiveness and equity acceptably. We present both an exact solution method and a heuristic approach, based on the Large Neighborhood Search framework, which relies on the fact that a certain sub-problem is easy to solve. Numerical experiments on several real-life and randomly generated datasets confirm that high-quality solutions may be obtained.

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• The online appendix can be obtained here.

• The datasets mentioned in the paper can be downloaded here.

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A Segment-Based Formulation and a Matheuristic for the Humanitarian Pickup and Distribution Problem

Eisenhandler, O., and Tzur, M. (2019b). A segment-based formulation and a matheuristic for the humanitarian pickup and distribution problem. Transportation Science, 53(5), 1389-1408.

We present a novel formulation and a matheuristic for a rich humanitarian logistic problem that is motivated by the daily operation of food banks. The problem consists of collecting food donations from suppliers in the food industry and delivering them to food relief agencies that serve individuals in need. This setting requires simultaneous vehicle routing and resource allocation decisions, with the aim of balancing two possibly colliding goals: maximizing the total amount distributed and achieving equity in the allocation. The proposed formulation is based on certain properties satisfied by the optimal solution to the problem and is used within a framework of a broader solution method, which is shown to provide better performance compared to previously suggested methods. We demonstrate how the new approach can also be extended to the multi-vehicle counterpart, both with and without time windows.

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The Humanitarian Gleaning and Distribution Problem

Accepted for publication in IISE Transactions.

The datasets mentioned in the paper can be downloaded here.

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The Electric Dial-a-Ride Problem on Fixed Circuits

Working paper​

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