Hande Yaman

Skip or Insert? A Priori Optimization for the Vehicle Routing Problem with Time Windows and Stochastic Customers

  • Yulin Han
  • Hande Yaman
    • Categories Combinatorial Optimization, Production and Logistics, Stochastic Programming Tags , , , , , , ,

    We study an extension of the vehicle routing problem with time windows by incorporating stochastic customers, i.e., ad-hoc service requests. The uncertainty in stochastic customers is captured through scenarios. Two a priori optimization approaches, a classical and a new one lead to two different problems, both of which are modeled as scenario-based two-stage stochastic programs. … Read more

    Pessimistic bilevel optimization approach for decision-focused learning

  • Diego Jiménez
  • Bernardo K. Pagnoncelli
  • Hande Yaman
    • Categories 0-1 Programming, Stochastic Programming Tags , ,

    The recent interest in contextual optimization problems, where randomness is associated with side information, has led to two primary strategies for formulation and solution. The first, estimate-then-optimize, separates the estimation of the problem’s parameters from the optimization process. The second, decision-focused optimization, integrates the optimization problem’s structure directly into the prediction procedure. In this work, … Read more

    A Joint Demand and Supply Management Approach to Large Scale Urban Evacuation Planning: Evacuate or Shelter-in-Place, Staging and Dynamic Resource Allocation

  • Vedat Bayram
  • Hande Yaman
    • Categories (Mixed) Integer Linear Programming, Network Optimization, Transportation

    Urban evacuation management is challenging to implement as it requires planning and coordination over a large geographical area. To address these challenges and to bolster evacuation planning and management, joint supply and demand management strategies should be considered. In this study, we explore and jointly optimize evacuate or shelter-in-place, dynamic resource allocation, and staging decisions … Read more

    Two-Stage Facility Location Problems with Restricted Recourse

  • Esra Koca
  • Nilay Noyan
  • Hande Yaman
    • Categories Stochastic Programming

    We introduce a new class of two-stage stochastic uncapacitated facility location problems under system nervousness considerations. The location and allocation decisions are made under uncertainty, while the allocation decisions may be altered in response to the realizations of the uncertain parameters. A practical concern is that the uncertainty-adaptive second-stage allocation decisions might substantially deviate from … Read more

    An Exact Solution Approach for the Inventory Routing Problem with Time Windows

  • Esra Koca
  • Gizem Ozbaygin
  • Hande Yaman
    • Categories Applications - OR and Management Sciences, Production and Logistics, Transportation

    The inventory routing problem (IRP) is an integrated inventory and transportation planning problem that jointly determines the replenishment schedules for a given set of retailers, and the routing decisions for a supplier that distributes a product to the retailers over a finite planning horizon typically consisting of multiple periods. In the classical IRP, retailers are … Read more

    Hub Location and Route Dimensioning: Strategic and Tactical Intermodal Transportation Hub Network Design

  • Oya Ekin Karasan
  • Hande Yaman
  • Barış Yıldız
    • Categories Applications - OR and Management Sciences, Combinatorial Optimization, Transportation Tags , , , , ,

    We propose a novel hub location model that jointly eliminates the traditional assumptions on the structure of the network and on the discount due to economies of scale in an effort to better reflect real-world logistics and transportation systems. Our model extends the hub literature in various facets: instead of connecting non-hub nodes directly to … Read more

    Team as a Service: Team Formation on Social Networks

  • Nihal Berktas
  • Hande Yaman
    • Categories 0-1 Programming, Applications - OR and Management Sciences Tags , , , ,

    Team as a Service (TaaS) is a new outsourcing service that enables on-demand creation and management of distributed teams for fast growing companies. The companies that use the TaaS model form a team according to the needs of a given project and provide managerial service throughout. Motivated by this new application, we study the Team … Read more

    Multi-stage Stochastic Programming for Demand Response Optimization

  • Özlem Cavus
  • Hande Yaman
  • Munise Kübra Şahin
    • Categories (Mixed) Integer Nonlinear Programming, Applications - OR and Management Sciences, Stochastic Programming Tags , , ,

    The increase in the energy consumption puts pressure on natural resources and environment and results in a rise in the price of energy. This motivates residents to schedule their energy consumption through demand response mechanism. We propose a multi-stage stochastic programming model to schedule different kinds of electrical appliances under uncertain weather conditions and availability … Read more

    A Branch-and-Price Algorithm for the Vehicle Routing Problem with Roaming Delivery Locations

  • Oya Ekin Karasan
  • Gizem Ozbaygin
  • Martin Savelsbergh
  • Hande Yaman
    • Categories Integer Programming, Network Optimization, Transportation Tags , , , ,

    We study the vehicle routing problem with roaming delivery locations in which the goal is to find a least-cost set of delivery routes for a fleet of capacitated vehicles and in which a customer order has to be delivered to the trunk of the customer’s car during the time that the car is parked at … 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