Sökning: "Lagrangian Relaxation"

Visar resultat 1 - 5 av 12 uppsatser innehållade orden Lagrangian Relaxation.

  1. 1. Lagrangian Bounding and Heuristics for Bi-Objective Discrete Optimisation

    Kandidat-uppsats, Linköpings universitet/Tillämpad matematik; Linköpings universitet/Tekniska fakulteten

    Författare :Ida Åkerholm; [2022]
    Nyckelord :Lagrangian relaxation; bi-objective optimisation; Pareto frontier; heuristics; discrete optimisation;

    Sammanfattning : For larger instances of multi-objective optimisation problems, the exact Pareto frontier can be both difficult and time-consuming to calculate. There is a wide range of methods to find feasible solutions to such problems, but techniques for finding good optimistic bounds to compare the feasible solutions with are missing. LÄS MER

  3. 2. Location Planning Considering Delivery Time and Service Level Constraints A Heuristic Solution Approach to a Linear Optimization Problem from an Automotive Spare Parts Network

    Master-uppsats, Göteborgs universitet/Graduate School

    Författare :Alexander Zienau; [2018-07-02]
    Nyckelord :network design; location problem; delivery time; outliers; linear optimization; heuristic; Lagrangian relaxation; knapsack problem; spare parts network; automotive industry;

    Sammanfattning : This thesis addresses the challenge to model a warehouse location problem under consideration of delivery time and service level constraints. For identification of appropriate modelling techniques, literature research is conducted to identify relevant models using similar approaches. LÄS MER

  4. 3. Probabilistic Multidisciplinary Design Optimization on a high-pressure sandwich wall in a rocket engine application

    Master-uppsats, Umeå universitet/Institutionen för fysik

    Författare :Dennis Wahlström; [2017]
    Nyckelord :Multidisciplinary Design Optimization; Analytical Target Cascading; Multidisciplinary Feasible; Space Nozzle; Ariane; Expander Cycle Engine; Upper stage space rocket engine; Probabilistic; Augmented Lagrangian relaxation; Finite element; Solid Mechanics; Thermodynamics; Aerodynamics; Industrial approach; Latin Hypercube Sampling; Factorial Analysis; Analysis of Variance;

    Sammanfattning : A need to find better achievement has always been required in the space industrythrough time. Advanced technologies are provided to accomplish goals for humanityfor space explorer and space missions, to apprehend answers and widen knowledges. LÄS MER

  5. 4. Numerical approach of a hybrid rocket engine behaviour : Modelling the liquid oxidizer injection using a Lagrangian solver

    Master-uppsats, KTH/Mekanik

    Författare :Gustave Sporschill; [2017]
    Nyckelord :Hybrid propulsion; combustion; numerical simulations; two-phase flow; La-grangian approach;

    Sammanfattning : To access and operate in space, a wide range of propulsion systems has been developed, from high-thrust chemical propulsion to low-thrust electrical propulsion, and new kind of systems are considered, such as solar sails and nuclear propulsion. Recently, interest in hybrid rocket engines has been renewed due to their attractive features (safe, cheap, flexible) and they are now investigated and developed by research laboratories such as ONERA. LÄS MER

  7. 5. Finding the Densest Common Subgraph with Linear Programming

    Kandidat-uppsats, Göteborgs universitet/Institutionen för data- och informationsteknik

    Författare :Alexander Reinthal; Anton T örnqvist; Arvid Andersson; Erik Norlander; Philip Stålhammar; Sebastian Norlin; [2016-11-15]
    Nyckelord :Linear Programming; Graph theory; Dense Subgraphs; Densest Common Subgraph;

    Sammanfattning : This thesis studies the concept of dense subgraphs, speci cally for graphs with multiple edge sets. Our work improves the running time of an existing Linear Program (LP) for solving the Densest Common Subgraph problem. LÄS MER