Sökning: "L Alfredsson"

Hittade 5 avhandlingar innehållade orden L Alfredsson.

  1. 1. Fatigue crack growth experiments and analyses - from small scale to large scale yielding at constant and variable amplitude loading

    Författare :Pär Ljustell; Fred L. Nilsson; Bo Alfredsson; Gunnar Härkegård; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fracture mechanics; fatigue crack growth; finite elements analysis; small scale yielding SSY ; large scale yielding LSY ; low cycle fatigue LCF ; crack tip opening displacement CTOD ; crack closure; potential drop method; constant amplitude load; variable amplitude load; inconel 718; stainless steel 316L;

    Sammanfattning : This thesis is on fatigue crack growth experiments and assessments of fatigue crack growth rates. Both constant and variable amplitude loads in two different materials are considered; a nickel based super-alloy Inconel 718 and a stainless steel 316L. LÄS MER

  3. 2. Experimental studies of wind turbine wakes : power optimisation and meandering

    Författare :Davide Medici; Henrik Alfredsson; Martin O.L. Lansen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wind energy; power optimisation; active control; yaw; vortex shedding; wake meandering; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : Wind tunnel studies of the wake behind model wind turbines with one, two and three blades have been made in order to get a better understanding of wake development as well as the possibility to predict the power output from downstream turbines working in the wake of an upstream one. Both two-component hot-wire anemometry and particle image velocimetry (PIV) have been used to map the flow field downstream as well as upstream the turbine. LÄS MER

  4. 3. TCP in Wireless Networks: Challenges, Optimizations and Evaluations

    Författare :Stefan Alfredsson; Anna Brunström; Lars-Åke Larzon; Karlstads universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wireless networks; TCP IP; TCP-L; Network emulation; Computer science; Datavetenskap; Computer Science; Datavetenskap;

    Sammanfattning : This thesis presents research on transport layer behavior in wireless networks. As the Internet is expanding its reach to include mobile devices, it has become apparent that some of the original design assumptions for the dominant transport protocol, TCP, are approaching their limits. LÄS MER

  5. 4. Functional organisation of the cell nucleus in the fission yeast, Schizosaccharomyces pombe

    Författare :Jenny Alfredsson Timmins; Pernilla Bjerling; Wendy Bickmore; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; fission yeast; heterochromatin; subnuclear organisation; chromo domain proteins; boundary elements; transcriptional regulation; epigenetics; Molecular biology; Molekylärbiologi; Cell and molecular biology; Cell- och molekylärbiologi; Genetics; Genetik; Molecular Biology; molekylärbiologi; Genetics; genetik;

    Sammanfattning : In eukaryotes the genome adopts a non-random spatial organisation, which is important for gene regulation. However, very little is known about the driving forces behind nuclear organisation. LÄS MER

  7. 5. Experimental studies in jet flows and zero pressure-gradient turbulent boundary layers

    Författare :Ramis Örlü; P. Henrik Alfredsson; Tim B. Nickels; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Axisymmetric jet; swirling jet; coaxial jet; heated jet; zero pressuregradient turbulent boundary layer; wall-bounded turbulent flows; overlap region; passive scalar mixing; hot-wire anemometry; spatial resolution.; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : This thesis deals with the description and development of two classical turbulent shear flows, namely free jet and flat plate turbulent boundary layer flows. In both cases new experimental data has been obtained and in the latter case comparisons are also made with data obtained from data bases, both of experimental and numerical origin. LÄS MER