Applications – OR and Management Sciences

Capturing Unit Startup and Shutdown Uncertainties in the Real-time Commitment Process

  • Yonghong Chen
  • Bernard Knueven
  • Mohammad Faqiry
  • Anupam Thatte
  • Jianhui Wang
  • Shengfei Yin
  • Long Zhao
    • Categories Applications - OR and Management Sciences Tags , , , ,

    Generation uncertainties, especially during the unit startup and shutdown (SU/SD) processes, pose uncertainties for the real-time market clearing process, and they are often underestimated. This paper proposes two approaches to predict generator SU/SD trajectories in the real-time operations of independent system operators or regional transmission organizations (ISO/RTOs). We first collect and pre-process raw market data … Read more

    A decomposition approach for integrated locomotive scheduling and driver rostering in rail freight transport

  • Andreas Bärmann
  • Alexander Martin
  • Jonasz Staszek
    • Categories 0-1 Programming, Cutting Plane Approaches, Transportation Tags , , , ,

    In this work, we consider the integrated problem of locomotive scheduling and driver rostering in rail freight companies. Our aim is to compute an optimal simultaneous assignment of locomotives and drivers to the trains listed in a given order book. Mathematically, this leads to the combination of a set-packing problem with compatibility constraints and a … Read more

    Learning Optimal Prescriptive Trees from Observational Data

  • Nathanael Jo
  • Sina Aghaei
  • Andrés Gómez
  • Phebe Vayanos
    • Categories (Mixed) Integer Linear Programming, Applications - OR and Management Sciences Tags , , , ,

    We consider the problem of learning an optimal prescriptive tree (i.e., an interpretable treatment assignment policy in the form of a binary tree) of moderate depth, from observational data. This problem arises in numerous socially important domains such as public health and personalized medicine, where interpretable and data-driven interventions are sought based on data gathered … Read more

    Determining locations and layouts for parcel lockers to support supply chain viability at the last mile

  • Michael Kahr
    • Categories (Mixed) Integer Linear Programming, Facility Planning and Design, Transportation Tags , , , ,

    The pandemic caused by the corona virus SARS-CoV-2 raised many new challenges for humanity. For instance, governments imposed regulations such as lockdowns, resulting in supply chain shocks at different tiers. Additionally, delivery services reached their capacity limits because the demand for mail orders soared temporarily during the lockdowns. We argue that one option to support … Read more

    The probabilistic travelling salesman problem with crowdsourcing

  • Alberto Santini
  • Ana Viana
  • Xenia Klimentova
  • João Pedro Pedroso
    • Categories Stochastic Programming, Supply Chain Management Tags , ,

    We study a variant of the Probabilistic Travelling Salesman Problem arising when retailers crowdsource last-mile deliveries to their own customers, who can refuse or accept in exchange for a reward. A planner must identify which deliveries to offer, knowing that all deliveries need fulfilment, either via crowdsourcing or using the retailer’s own vehicle. We formalise … Read more

    Linearizing Bilinear Products of Shadow Prices and Dispatch Variables in Bilevel Problems for Optimal Power System Planning

  • Grani A. Hanasusanto
  • Nicholas Laws
    • Categories Applications - OR and Management Sciences, Applications - Science and Engineering, Energy Tags , , , ,

    This work presents a general method for linearizing bilinear terms in the upper level of bilevel optimization problems when the bilinear terms are products of the primal and dual variables of the lower level. Bilinear terms of this form often appear in energy market optimization models where the dual variable represents the market price of … Read more

    Appointment Scheduling for Medical Diagnostic Centers considering Time-sensitive Pharmaceuticals: A Dynamic Robust Optimization Approach

  • Aleida Braaksma
  • Mohammad Mahdavi Mazdeh
  • Mahdi Heydari
  • Mohammad Namakshenas
    • Categories Applications - OR and Management Sciences, Convex and Nonsmooth Optimization, Robust Optimization Tags , , , , ,

    This paper studies optimal criteria for the appointment scheduling of outpatients in a medical imaging center. The main goal of this study is to coordinate the assignments of radiopharmaceuticals and the scheduling of outpatients on imaging scanners. We study a special case of a molecular imaging center that offers services for various diagnostic procedures for … Read more

    Mathematical models for the minimization of open stacks problem

  • Maria José Pinto
  • Horacio Hideki Yanasse
  • Mateus Martin
    • Categories Applications - OR and Management Sciences Tags , , , ,

    In this paper, we address the Minimization of Open Stacks Problem (MOSP). This problem often appears during production planning of manufacturing industries, such as in the cutting of objects to comply with space constraints around the cutting machine in the glass, furniture, and metallurgical industries. The MOSP is also pertinent to the field of VLSI … Read more

    MILP models for the continuous Berth Allocation and Quay Crane Assignment Problem considering crane movement and setup times

  • Ramon Alvarez-Valdes
  • Juan F. Correcher
  • Federico Perea
    • Categories (Mixed) Integer Linear Programming, Scheduling, Transportation Tags , , ,

    In this technical report we present several Mixed Integer Linear Programming (MILP) models for the Berth Allocation and Quay Crane Assignment Problem (BACASP) considering crane movement and setup time (from now on: BACASP-S). First, we propose a MILP for the continuous-quay time-invariant BACASP in which both berthing time and position variables are continuous. Then, we … Read more

    Energy-efficient Automated Vertical Farms

  • Maxence Delorme
  • Alberto Santini
    • Categories Combinatorial Optimization, Production and Logistics Tags , , , ,

    Autonomous vertical farms (VFs) are becoming increasingly more popular, because they allow to grow food minimising water consumption and the use of pesticides, while greatly increasing the yield per square metre, compared with traditional agriculture. To meet sustainability goals, however, VFs must operate at maximum efficiency; it would be otherwise impossible to compete with the … Read more