Sökning: "lokala nät"

Visar resultat 6 - 10 av 10 avhandlingar innehållade orden lokala nät.

  1. 6. Uncertainty quantification for high frequency waves

    Författare :Gabriela Malenova; Olof Runborg; Fabio Nobile; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Matematik;

    Sammanfattning : We consider high frequency waves satisfying the scalar wave equation with highly oscillatory initial data represented by a short wavelength ε. The speed of propagation of the medium as well as the phase and amplitude of the initial data is assumed to be uncertain, described by a finite number of independent random variables with known probability distributions. LÄS MER

  3. 7. Topology optimization of transitional flows

    Författare :Harrison Nobis; Dan Henningson; Philipp Schlatter; Paolo Luchini; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct Numerical Simulation; Topology Optimization; Laminar– Turbulent Transition; Spectral Element Method; Direkt numerisk simulering; topologioptimering; laminär–turbulent omslag; spektralelementmetod; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : This thesis is concerned with the application of topology optimization in thedesign of structures that control fluids. A framework is developed in the high-order Spectral Element Method (SEM) code Nek5000, extending Nek5000 fromits original capabilities, performing Direct Numerical Simulations (DNS), toperforming density-based topology optimization. LÄS MER

  4. 8. Flood Hazard Assessment in Data-Scarce Basins : Use of alternative data and modelling techniques

    Författare :Diana Fuentes-Andino; Sven Halldin; Chong-Yu Xu; Keith Beven; Giuliano Di Baldassarre; Wouter Buytaert; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Central America; floods; data scarcity; data quality; uncertainty analysis; regionalisation; flood frequency analysis; GLUE; hydraulic modelling; rainfall-runoff modeling; TOPMODEL; LISFLOOD-FP; GRADEX; index-flood; Muskingum-Cunge-Todini flow routing; Mellanamerika; högflöde; datakvalitet; osäkerhetsanalys; regionalisering; frekvensanalys av högflöden; GLUE; hydraulisk modellering; nederbörds-avrinningsmodeller; TOPMODEL; LISFLOOD-FP; GRADEX; indexflöde; Muskingum-Cunge-Todini flödessvarstid; Central América; inundaciones; escasez de datos; calidad de los datos; análisis de incertidumbre; regionalización; análisis de frequencia de inundación; GLUE; modelación hidraulica; modelo de lluvia-escorrentía; TOPMODEL; LISFLOOD-FP; GRADEX; índice de inundación; Muskingum-Cunge-Todini rutina de propagación de flujo;

    Sammanfattning : Flooding is of great concern world-wide, causing damage to infrastructure, property and loss of life. Low-income countries, in particular, can be negatively affected by flood events due to their inherent vulnerabilities. Moreover, data to perform studies for flood risk management in low-income regions are often scarce or lacking sufficient quality. LÄS MER

  5. 9. Decentralized Learning of Randomization-based Neural Networks

    Författare :Xinyue Liang; Saikat Chatterjee; Mikael Skoglund; Nikolaos Deligiannis; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Machine learning and artificial intelligence have been wildly explored and developed very fast to adapt to the expanding need for almost every aspect of human development. When stepping into the big data era, siloed data localization has become a big challenge for machine learning. LÄS MER

  7. 10. Fundamental Control Performance Limitations for Interarea Oscillation Damping and Frequency Stability

    Författare :Joakim Björk; Karl H. Johansson; Lennart Harnefors; Joe H. Chow; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Power system control; HVDC transmission control; interarea oscillations; power oscillation damping; small-signal stability; fundamental control limitations; frequency stability; hydro power; wind power; non-minimum phase; zero dynamics; eigenvalue analysis; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : With the transition towards renewable energy and the deregulation of the electricity markets, the power system is changing. Growing electricity demand and more intermittent power production increase the need for transfer capacity. Lower inertia levels due to a higher share of renewables increase the need for fast frequency reserves (FFR). LÄS MER