Applications – Science and Engineering

Clustering methods to find representative periods for the optimization of energy systems: an initial framework and comparison

  • Adam R. Brandt
  • Holger Teichgraeber
    • Categories Applications - Science and Engineering, Chemical Engineering, Energy Tags , , , , ,

    Modeling time-varying operations in complex energy systems optimization problems is often computationally intractable, and time-series input data are thus often aggregated to representative periods. In this work, we introduce a framework for using clustering methods for this purpose, and we compare both conventionally-used methods (k-means, k-medoids, and hierarchical clustering), and shape-based clustering methods (dynamic time … Read more

    Location and Capacity Planning of Facilities with General Service-Time Distributions Using Conic Optimization

  • Ahmadi-Javid Amir
  • Oded Berman
  • Pooya Hoseinpour
    • Categories (Mixed) Integer Nonlinear Programming, Applications - OR and Management Sciences, Facility Planning and Design

    This paper studies a stochastic congested location problem in the network of a service system that consists of facilities to be established in a finite number of candidate locations. Population zones allocated to each open service facility together creates a stream of demand that follows a Poisson process and may cause congestion at the facility. … Read more

    A mixed-integer fractional optimization approach to best subset selection

  • Andrés Gómez
  • Oleg A. Prokopyev
    • Categories (Mixed) Integer Nonlinear Programming, Branch and Cut Algorithms, Statistics Tags , , ,

    We consider the best subset selection problem in linear regression, i.e., finding a parsimonious subset of the regression variables that provides the best fit to the data according to some predefined criterion. We show that, for a broad range of criteria used in the statistics literature, the best subset selection problem can be modeled as … Read more

    An Integer Programming Formulation of the Key Management Problem in Wireless Sensor Networks

  • Maciej Rysz
  • Alexander Semenov
  • Guanglin Xu
    • Categories 0-1 Programming, Multidisciplinary Design Optimization, Telecommunications Tags , , , ,

    With the advent of modern communications systems, much attention has been put on developing methods for securely transferring information between constituents of wireless sensor networks. To this effect, we introduce a mathematical programming formulation for the key management problem, which broadly serves as a mechanism for encrypting communications. In particular, an integer programming model of … Read more

    Time-Varying Semidefinite Programs

  • Amir Ali Ahmadi
  • Bachir El Khadir
    • Categories Basic Sciences Applications, Infinite Dimensional Optimization, Semi-definite Programming Tags , , , , ,

    We study time-varying semidefinite programs (TV-SDPs), which are semidefinite programs whose data (and solutions) are functions of time. Our focus is on the setting where the data varies polynomially with time. We show that under a strict feasibility assumption, restricting the solutions to also be polynomial functions of time does not change the optimal value … Read more

    ACQUIRE: an inexact iteratively reweighted norm approach for TV-based Poisson image restoration

  • Daniela di Serafino
  • Germana Landi
  • Marco Viola
    • Categories Applications - Science and Engineering, Convex and Nonsmooth Optimization Tags , , , ,

    We propose a method, called ACQUIRE, for the solution of constrained optimization problems modeling the restoration of images corrupted by Poisson noise. The objective function is the sum of a generalized Kullback-Leibler divergence term and a TV regularizer, subject to nonnegativity and possibly other constraints, such as flux conservation. ACQUIRE is a line-search method that … Read more

    Resilience assessment for interdependent urban infrastructure systems using dynamic network flow models

  • Panagiotis Angeloudis
  • Nils Goldbeck
  • Washington Ochieng
    • Categories Civil and Environmental Engineering, Optimization of Simulated Systems, Transportation

    Critical infrastructure systems in cities are becoming increasingly interdependent, therefore exacerbating the impacts of disruptive events through cascading failures, hindered asset repairs and network congestion. Current resilience assessment methods fall short of fully capturing such interdependency effects as they tend to model asset reliability and network flows separately and often rely on static flow assignment … Read more

    Predicting the vibroacoustic quality of steering gears

  • Paul Alexandru Bucur
  • Philipp Hungerländer
  • Klaus Frick
    • Categories Data-Mining, Mechanical Engineering, Statistics Tags , , ,

    In the daily operations of ThyssenKrupp Presta AG, ball nut assemblies (BNA) undergo a vibroacoustical quality test and are binary classified based on their order spectra. In this work we formulate a multiple change point problem and derive optimal quality intervals and thresholds for the order spectra that minimize the number of incorrectly classified BNA. … Read more

    Leveraging Predictive Analytics to Control and Coordinate Operations, Asset Loading and Maintenance

  • Nagi Gebraeel
  • Xu Andy Sun
  • Murat Yildirim
    • Categories Applications - OR and Management Sciences, Energy, Scheduling Tags , , , ,

    This paper aims to advance decision-making in power systems by proposing an integrated framework that combines sensor data analytics and optimization. Our modeling framework consists of two components: (1) a predictive analytics methodology that uses real-time sensor data to predict future degradation and remaining lifetime of generators as a function of the loading conditions, and … Read more

    Efficient Solution of Maximum-Entropy Sampling Problems

  • Kurt M. Anstreicher
    • Categories (Mixed) Integer Nonlinear Programming, Convex Optimization, Statistics Tags , ,

    We consider a new approach for the maximum-entropy sampling problem (MESP) that is based on bounds obtained by maximizing a function of the form ldet M(x) over linear constraints, where M(x)is linear in the n-vector x. These bounds can be computed very efficiently and are superior to all previously known bounds for MESP on most … Read more