Applications – OR and Management Sciences

A Decision Diagram Approach for the Parallel Machine Scheduling Problem with Chance Constraints

  • Nicolás Casassus
  • Margarita P Castro
  • Gustavo Angulo
    • Categories Branch and Cut Algorithms, Scheduling, Stochastic Programming Tags , ,

    The Chance-Constrained Parallel Machine Scheduling Problem (CC-PMSP) assigns jobs with uncertain processing times to machines, ensuring that each machine’s availability constraints are met with a certain probability. We present a decomposition approach where the master problem assigns jobs to machines, and the subproblems schedule the jobs on each machine while verifying the solution’s feasibility under … Read more

    Data-driven robust menu planning for food services: Reducing food waste by using leftovers

  • Marloes Remijnse
  • Marjolein Buisman
  • Ahmadreza Marandi
  • S.U.K Rohmer
  • Tom Van Woensel
    • Categories (Mixed) Integer Linear Programming, Applications - OR and Management Sciences, Robust Optimization Tags , , , ,

    With food waste levels of about 30%, mostly caused by overproduction, reducing food waste poses an important challenge in the food service sector. As food is prepared in advance rather than on demand, there is a significant risk that meals or meal components remain uneaten. Flexible meal planning can promote the reuse of these leftovers … Read more

    Arc-Based Dynamic Discretization Discovery for Continuous-Time Service Network Design

  • Alexander Helber
    • Categories Combinatorial Optimization, Network Optimization, Transportation Tags , , ,

    In the continuous time service network design problem, a freight carrier decides the path of shipments in their network as well as the dispatch times of the vehicles transporting the shipments. State-of-the-art algorithms to solve this problem are based on the dynamic discretization discovery framework. These algorithms solve a relaxation of the problem using a … Read more

    Time Complexity and Optimality of Inventory and Production Policies for a Dynamic Lot Sizing Model with Remanufacturing and Separate Setup Costs

  • Chee-Khian Sim
    • Categories Dynamic Programming, Production and Logistics Tags , , ,

    We consider a dynamic lot sizing model in which end products to satisfy demands are obtained by remanufacturing m types of cores or manufacturing from raw materials. We consider separate setup costs for manufacturing and remanufacturing in our model. It is conjectured in [21], with reference to [24], that finding an optimal policy to the … Read more

    Recursive Partitioning and Batching for Network Design with Service Time Guarantees at Massive Scale

  • Myungeun Eom
  • Alan L. Erera
  • Alejandro Toriello
    • Categories Production and Logistics, Supply Chain Management, Transportation Tags , , , ,

    Motivated by the parcel delivery industry, we study a network design problem with service time guarantees at industrial scale. This tactical service network design problem determines primary paths and delivery schedules for commodities to minimize transportation and handling costs while ensuring committed service times. To construct a solution for a real-world instance with over 1,000 … Read more

    Cost allocation in maintenance clustering

  • Andries van Beek
  • Loe Schlicher
    • Categories Applications - OR and Management Sciences, Game Theory Tags , , , ,

    Inspired by collaborative initiatives in the military domain, we analyze a setting in which multiple different players (e.g., Ministries of Defence) have to carry out preventive maintenance jobs. Each player is responsible for one job, with a job-specific minimal frequency and with maintenance costs, consisting of a job-specific variable component and a fixed component, which … Read more

    Strategic design of collection and delivery point networks for urban parcel distribution

  • Benjamin Rojas
  • Homero Larrain
  • Mathias A. Klapp
    • Categories Applications - OR and Management Sciences, Production and Logistics, Transportation Tags , , ,

    Collection and delivery points (CDPs) allow logistics operators to consolidate multiple customer request deliveries on a single vehicle stop, reducing distribution costs. However, for customers to adopt CDPs, they must be willing to travel to a nearby CDP to pick up their parcels. This choice depends on the customer’s personal preferences, the proximity of CDPs, … Read more

    A constraint programming model and a hybrid iterated local search algorithm for solving an aircraft recovery problem in the oil and gas industry

  • Mateus Martin
  • Aldair Álvarez
  • Jonathan De La Vega
  • Reinaldo Morabito
    • Categories Applications - OR and Management Sciences, Other Topics Tags , , , ,

    In this paper, we address a challenging problem faced by a Brazilian oil and gas company regarding the rescheduling of helicopter flights from an onshore airport to maritime units, crucial for transporting company employees. The problem arises due to unforeseen events like bad weather or mechanical failures, leading to delays or postponements in the original … Read more

    Obscured by terminology: Hidden parallels in direct methods for open-loop optimal control

  • Susanne Sass
  • Alexander Mitsos
    • Categories Control Applications, Scheduling, Systems governed by Differential Equations Optimization Tags , , , , ,

    Active research on optimal control methods comprises the developments of research groups from various fields, including control, mathematics, and process systems engineering. Although there is a consensus on the classification of the main solution methods, different terms are often used for the same method. For example, solving optimal control problems with control discretization and embedded … Read more

    A Branch and Price Algorithm for Scheduling in Surgery Pre-admission Testing Clinics

  • Ankit Bansal
    • Categories 0-1 Programming, Combinatorial Optimization, Scheduling Tags , , , ,

    A Surgery Pre-Admission Testing (PAT) clinic is a hospital unit designed to serve pre-operative patients by gathering critical patient information and performing procedure-specific tests to prepare them for surgery. Patients may require multiple tests, each conducted by a specialized nurse. A patient must be assigned to a room before starting any test and must stay … Read more