Applications – OR and Management Sciences

Application of the Laminar Navier-Stokes Equations for Solving 2D and 3D Pathfinding Problems with Static and Dynamic Spatial Constraints. Implementation and validation in Comsol Multiphysics.

  • Benjamin Ivorra
    • Categories Applications - Science and Engineering, Other Topics, Transportation

    Pathfinding problems consist in determining the optimal shortest path, or at least one path, between two points in the space. In this paper, we propose a particular approach, based on methods used in Computational Fluid Dynamics, that intends to solve such problems. In particular, we reformulate pathfinding problems as the motion of a viscous fluid … Read more

    A Multi-Objective approach to visualize proportions and similarities between individuals by rectangular maps

  • Emilio Carrizosa
  • Dolores Romero Morales
  • Vanesa Guerrero
    • Categories Applications - OR and Management Sciences Tags , , ,

    In this paper we address the problem of visualizing the proportions and the similarities attached to a set of individuals. We represent this information using a rectangular map, i.e., a subdivision of a rectangle into rectangular portions so that each portion is associated with one individual, their areas reflect the proportions, and the closeness between … Read more

    Visualizing data as objects by DC (difference of convex) optimization

  • Emilio Carrizosa
  • Dolores Romero Morales
  • Vanesa Guerrero
    • Categories Applications - OR and Management Sciences Tags , , ,

    In this paper we address the problem of visualizing in a bounded region a set of individuals, which has attached a dissimilarity measure and a statistical value. This problem, which extends the standard Multidimensional Scaling Analysis, is written as a global optimization problem whose objective is the difference of two convex functions (DC). Suitable DC … Read more

    Distributionally robust inventory control when demand is a martingale

  • David A. Goldberg
  • Linwei Xin
    • Categories Applications - OR and Management Sciences, Robust Optimization, Stochastic Programming Tags , , , , ,

    Demand forecasting plays an important role in many inventory control problems. To mitigate the potential harms of model misspecification in this context, various forms of distributionally robust optimization have been applied. Although many of these methodologies suffer from the problem of time-inconsistency, the work of Klabjan, Simchi-Levi and Song [85] established a general time-consistent framework … Read more

    Network Design Problem with Relays

  • Oya Ekin Karasan
  • Hande Yaman
  • Baris Yildiz
    • Categories Applications - OR and Management Sciences, Telecommunications, Transportation Tags , , ,

    Relays are regenerators extending the reach of optical signals in telecommunication networks; they may be strategic locations where exchange of drivers, trucks or mode of transportation takes place in transportation networks; they may become refuelling/recharging stations extending the reach of alternative fuel vehicles in green transportation. With different names and characteristics, relays play a crucial … Read more

    Branch and Price for Chance Constrained Bin Packing

  • Brian T. Denton
  • Xiaolan Xie
  • Z. Zhang
    • Categories Applications - OR and Management Sciences, Stochastic Programming

    This article considers two versions of the stochastic bin packing problem with chance constraints. In the first version, we formulate the problem as a two-stage stochastic integer program that considers item-to-bin allocation decisions in the context of chance constraints on total item size within the bins. Next, we describe a distributionally robust formulation of the … Read more

    Partial outer convexification for traffic light optimization in road networks

  • Simone Göttlich
  • Andreas Potschka
  • Ute Ziegler
    • Categories (Mixed) Integer Nonlinear Programming, Optimization of Systems modeled by PDEs, Transportation Tags , , , ,

    We consider the problem of computing optimal traffic light programs for urban road intersections using traffic flow conservation laws on networks. Based on a Partial Outer Convexification approach, which has been successfully applied in the area of mixed-integer optimal control for systems of ordinary or differential algebraic equations, we develop a computationally tractable two-stage solution … Read more

    Estimating Portfolio Loss Probabilities with Optimal Risk Loading Coefficients and Fixed Dependency among Obligors

  • Ioannis G. Akrotirianakis
  • Amit Chakraborty
  • Xi He
    • Categories Finance and Economics Tags , ,

    We consider the problem of measuring risk of a portfolio com- prising loans, bonds, and financial instruments, which is caused by possible default of its obligors. Specifically, we are interested in esti- mating probability that a portfolio incurs large loss over a fixed time horizon. One crucial concern of such problem is how to measure … Read more

    Free-Floating Bike Sharing: Solving Real-life Large-scale Static Rebalancing Problems

  • Aritra Pal
  • Yu Zhang
    • Categories Civil and Environmental Engineering, Meta Heuristics, Transportation Tags , , , ,

    Free-floating bike sharing (FFBS) is an innovative bike sharing model. FFBS saves on start-up cost, in comparison to station-based bike sharing (SBBS), by avoiding construction of expensive docking stations and kiosk machines. FFBS prevents bike theft and offers significant opportunities for smart management by tracking bikes in real-time with built-in GPS. However, like SBBS, the … Read more

    A two-level SDDP Solving Strategy with Risk-Averse multivariate reservoir Storage Levels for Long Term power Generation Planning

  • Andre Diniz
  • Maria Elvira P. Maceira
  • D.D. Penna
  • C. L. Vasconcellos
    • Categories Applications - OR and Management Sciences, Stochastic Programming Tags , ,

    Power generation planning in large-scale hydrothermal systems is a complex optimization task, specially due to the high uncertainty in the inflows to hydro plants. Since it is impossible to traverse the huge scenario tree of the multi-stage problem, stochastic dual dynamic programming (SDDP) is the leading optimization technique to solve it, originally from an expected-cost … Read more