Sökning: "cascade"

Visar resultat 16 - 20 av 484 avhandlingar innehållade ordet cascade.

  1. 16. Statistical characteristics of two-dimensional and quasigeostrophic turbulence

    Författare :Andreas Vallgren; Erik Lindborg; Johan Nilsson; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; two-dimensional turbulence; decaying turbulence; quasigeostrophic turbulence; direct numerical simulation DNS ; coherent vortices; energy cas- cade; enstrophy cascade; intermittency; massively parallel simulations; Non-linear dynamics; chaos; Icke-linjär dynamik; kaos;

    Sammanfattning : Two codes have been developed and implemented for use on massively parallelsuper computers to simulate two-dimensional and quasigeostrophic turbulence.The codes have been found to scale well with increasing resolution and width ofthe simulations. LÄS MER

  3. 17. Human Interactions on Online Social Media : Collecting and Analyzing Social Interaction Networks

    Författare :Fredrik Erlandsson; Johnson Henric; Martin Boldt; Piotr Bródka; S. Felix Wu; Sune Lehmann; Blekinge Tekniska Högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Social Media; Social Networks; Crawling; Complex Networks; Information Cascade; Seed Selection; Privacy;

    Sammanfattning : Online social media, such as Facebook, Twitter, and LinkedIn, provides users with services that enable them to interact both globally and instantly. The nature of social media interactions follows a constantly growing pattern that requires selection mechanisms to find and analyze interesting data. LÄS MER

  4. 18. Runaway electrons and Alfvén eigenmodes in tokamaks

    Författare :Håkan Smith; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; two-way diffusion equation; compressional Alfvén eigenmode; fusion plasma physics; tokamak disruption; runaway electron; Alfvén cascade;

    Sammanfattning : Runaway electrons can be generated as a consequence of the rapid thermal quench of the plasma in a tokamak disruption. If the time scale of this cooling is short compared to the collision time in the tail of the electron velocity distribution, incomplete thermalisation of this tail leads to a burst of runaway production. LÄS MER

  5. 19. Turbine Outlet Guide Vane Flows

    Författare :Johan Hjärne; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Spalart-Allmaras model; k-ω SST model; linear cascade; secondary flows; turbine exhaust casing; RSM; k-ε realizable model; turbine rear frame; engine mount bump; tail bearing housing; Outlet guide vane;

    Sammanfattning : New design goals on modern jet engines often leads to more highly loaded turbines with fewer stages in order to save weight and cost. This gives higher swirl angles into the outlet guide vane (OGV), implying a more difficult aerodynamic design. LÄS MER

  7. 20. The cyanobacterial pigments scytonemin and nostodione A - Synthesis, photophysicochemical behavior and biological studies

    Författare :Andreas Ekebergh; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; UV-screeners; design of experiments; cascade reactions; palladium catalysis; nostodione A; ligand effect; gold catalysis; kinase inhibitor; Scytonemin; photo-stability;

    Sammanfattning : The natural UV-screener scytonemin is found in a plethora of cyanobacterial species. Its UV-protective ability allows the bacteria to thrive in inhospitable locations exposed to intense solar radiation. Scytonemin has a dimeric structure consisting of two 1-1' linked 3-(4-hydroxybenzylidene)cyclopenta[b]indole-2-one moieties. LÄS MER