Sökning: "scale formation"

Visar resultat 6 - 10 av 792 avhandlingar innehållade orden scale formation.

  1. 6. Unveiling a multi-scale view of massive star and cluster formation

    Författare :Chi Yan Law; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; massive stars; methods:observation; magnetic field; stars:formation; ISM:clouds;

    Sammanfattning : Massive stars regulate the physical and chemical evolution of galaxies. Most stars within these galaxies, including massive ones, appear to be born in star clusters. However, there are many open questions about how these systems form from diffuse interstellar gas. LÄS MER

  3. 7. Intrinsic Formation and Macroscopic Intervention in Multi-agent Systems

    Författare :Silun Zhang; Xiaoming Hu; Johan Karlsson; Jorge Goncalves; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Attitude control; agents and autonomous systems; distributed control; formation control; nonlinear systems; moment based modelling; large- scale systems; reduced order modeling; nonlinear system identification; Mathematics; Matematik;

    Sammanfattning : In this dissertation, we study two problems within the field of the multi-agent systems theory. One is the formation control for multiple reducedattitudes, which are extensively utilized in many pointing applications and under-actuated scenarios for attitude maneuvers. LÄS MER

  4. 8. The relationship between fly ash chemistry and the thermal formation of polychlorinated pollutants during waste incineration

    Författare :Duong Ngoc Chau Phan; Stellan Marklund; Bogdan Dlugogorski; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Incinerations; dioxins; PCDD Fs; PCBs; PCNs; flue gas; fly ash; sampling; particle characterization; XPS; XRD; SEM EDX; formation; chlorination; PCA; OPLS; OPLS-DA;

    Sammanfattning : The thermal formation of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and naphthalenes (PCNs) is a major problem in waste incineration. Ideally, rather than relying on air cleaning systems and treatment techniques, their formation should be minimized or, if possible eliminated. LÄS MER

  5. 9. On performance limitations of large-scale networks with distributed feedback control

    Författare :Emma Tegling; Henrik Sandberg; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Networked control systems; microgrids; platooning; vehicular formation; multi-agent systems; H2 norms; fundamental limitations; consensus; Distributed control; large-scale networks; oscillator networks; power networks; power system dynamics; system performance; spatially invariant systems; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : We address the question of performance of large-scale networks with distributed feedback control. We consider networked dynamical systems with single and double integrator dynamics, subject to distributed disturbances. We focus on two types of problems. First, we consider problems modeled over regular lattice structures. LÄS MER

  7. 10. Railway Wheel Flats. Martensite Formation, Residual Stresses, and Crack Propagation

    Författare :Johan Jergeus; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sliding contact; metallographic investigation; crack propagation; thermal shock; constitutive modelling; phase transformations; railway wheel flats; full-scale field experiments; transformation plasticity; tread damage; residual stresses; spalling; martensite formation;

    Sammanfattning : A railway wheel flat is a flat spot on the rolling surface of a wheel caused by its unintentional sliding on the rail. The reason for the sliding may be poorly adjusted, frozen or defect brakes, or too high braking forces in relation to the available wheel/rail adhesion. LÄS MER