ZIB

Treffer pro Seite

Treffer 1 - 2 | 2 Treffer

Sortierung

Unbekannt

Generative deep learning for decision making in gas networks (2022)

Anderson, Lovis ; Turner, Mark ; Koch, Thorsten (Prof. Dr.)

zur Merkliste hinzufügen auf der Merkliste

Details

Publikationsdatum: 2023-07-14

Beschreibung: A decision support system relies on frequent re-solving of similar problem instances. While the general structure remains the same in corresponding applications, the input parameters are updated on a regular basis. We propose a generative neural network design for learning integer decision variables of mixed-integer linear programming (MILP) formulations of these problems. We utilise a deep neural network discriminator and a MILP solver as our oracle to train our generative neural network. In this article, we present the results of our design applied to the transient gas optimisation problem. With the trained network we produce a feasible solution in 2.5s, use it as a warm-start solution, and thereby decrease global optimal solution solve time by 60.5%.

Sprache: Englisch

Materialart: article , doc-type:article

Permalink

Bibliothek	Standort	Signatur	Band/Heft/Jahr	Verfügbarkeit

Andere fanden auch interessant ...

OPUS

Überblick

Unbekannt

Viscosity and porosity effects on tangential-discontinuity surface stability in 3D Compressible Media (2022)

Le, Thi Thai (Dr.) ; Koch, Thorsten (Prof. Dr.)

zur Merkliste hinzufügen auf der Merkliste

Details

Publikationsdatum: 2024-04-26

Beschreibung: The stability of a flow in porous media relates to the velocity rate of injecting and withdrawing natural gases inside porous storage. We thus aim to analyze the stability of flows in porous media to accelerate the energy transition process. This research examines a flow model of a tangential--velocity discontinuity with porosity and viscosity changes in a three-dimensional (3D) compressible medium because of a co-existence of different gases in a storage. The fluids are assumed to move in a relative motion where the plane y=0 is a tangential-velocity discontinuity surface. We obtain that the critical value of the Mach number to stabilize a tangential discontinuity surface of flows via porous media is smaller than the one of flows in a plane. The critical value of the Mach number M to stabilize a discontinuity surface of the 3D flow is different by a factor |cosθ| compared to the two-dimensional (2D) flow. Here, θ is the angle between velocity and wavenumber vectors. Our results also show that the flow model with viscosity and porosity effects is stable faster than those without these terms. Our analysis is done for both infinite and finite flows. The effect of solid walls along the flow direction could suppress the instability, i.e., the tangential-discontinuity surface is stabilized faster

Sprache: Englisch

Materialart: article , doc-type:article

Permalink

Bibliothek	Standort	Signatur	Band/Heft/Jahr	Verfügbarkeit

Andere fanden auch interessant ...

OPUS

PDF

Überblick

Treffer 1 - 2 | 2 Treffer