Sökning: "mixed integer programming models"

Visar resultat 11 - 15 av 39 avhandlingar innehållade orden mixed integer programming models.

1. 11. Optimal Railroad Power Supply System Operation and Design : Detailed system studies, and aggregated investment models

   Författare :Lars Abrahamsson; Lennart Söder; Arnd Stephan; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Railway power supply systems (RPSSs) differ mainly from public power systems from that the loads are moving. These moving loads are motoring trains. Trains can also be regenerating when braking and are then power sources. These loads consume comparatively much power, causing substantial voltage drops, not rarely so big that the loads are reduced. LÄS MER

3. 12. On the Optimization of Schedules of a Multitask Production Cell

   Författare :Karin Thörnblad; Göteborgs universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; mathematical optimization; flexible job shop scheduling; mixed integer linear programming MILP ; complexity analysis; mathematical modelling; production planning; multi-purpose machine; dispatching rule; priority function; total flowtime; total tardiness; release date; due date; due date;

   Sammanfattning : Volvo Aero has invested in a complex production cell containing a set of multipurpose machines. The problem of finding optimal schedules for this multitask cell is a complex combinatorial optimization problem which is recognized as a flexible job shop problem. This thesis proposes an approach to find such schedules using mathematical optimization. LÄS MER

4. 13. Mathematical Optimization in Flexible Job Shop Scheduling: Modelling, Analysis, and Case Studies

   Författare :Karin Thörnblad; Göteborgs universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Flexible job shop scheduling; Mixed integer linear programming MILP ; Time-indexed formulation; Makespan; Tardiness; Fixture availability; Preventive maintenance; Night shift; Unmanned time window; Dynamic scheduling; Priority rules; Dispatching rules; Critical ratio; Night shift;

   Sammanfattning : The major theme of this thesis is the mathematical optimization modelling of the flexible job shop scheduling problem. This problem is present in the so-called multitask cell—a production cell at GKN Aerospace's facility located in Trollhättan, Sweden—which has served as a case study during the work with this thesis. LÄS MER

5. 14. Optimisation models for train timetabling and marshalling yard planning

   Författare :Sara Gestrelius; Anders Peterson; Martin Aronsson; Pieter Vansteenwegen; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Railways provide high capacity, safe and energy efficient transportation of goods and passengers. However, railway transportation also suffers from intrinsic restrictions and the effectiveness and efficiency of the transportation depend on the railway actors’ ability to solve a set of hard and interconnected planning problems. LÄS MER

7. 15. Planning Models for Single Wire Earth Return Power Distribution Networks

   Författare :Geofrey Bakkabulindi; Lennart Söder; Mikael Amelin; Peiyuan Chen; KTH; []
   Nyckelord :Rural electrification; power distribution planning; Single Wire Earth Return; distribution power flow; power system modeling; SRA - Energy; SRA - Energi;

   Sammanfattning : The high cost of grid extension to rural areas, often characterized by scattered communities with low load densities, requires the use of low cost electrification technologies to ensure economic viability. In Single Wire Earth Return (SWER) power distribution networks, the earth itself forms the current return path of the single phase system leading to significant cost savings on conductors, poles and poletop hardware compared to conventional systems. LÄS MER