Sökning: "Accelerated stress tests"

Visar resultat 1 - 5 av 13 avhandlingar innehållade orden Accelerated stress tests.

  1. 1. Telomeres and the brain : an investigation into the relationships of leukocyte telomere length with functional and structural attributes of the brain

    Författare :Mikael Wikgren; Karl-Fredrik Norrback; Rolf Adolfsson; Göran Roos; Thomas Karlsson; Brenda Penninx; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; APOE; aging; atrophy; brain; cognition; cortisol; depression; hippocampus; HPA axis; MRI; stress; telomere length; white matter hyper-intensities.;

    Sammanfattning : Telomeres are the outermost parts of linear chromosomes. They consist of tandemly repeated non-coding short nucleotide sequences (TTAGGG in all vertebrates), in humans spanning over the last 2 to 15 kilobase pairs of the chromosome. Due to the end-replication problem, telomeres shorten with each cellular division. LÄS MER

  3. 2. Materials Reliability in PEM Fuel Cells

    Författare :Live Mølmen; Peter Leisner; Ulf Jansson; Jönköping University; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fuel cell; PEMFC; Bipolar plate; Catalyst; Electrodeposition; Corrosion; Stainless steel; Accelerated stress tests; bränsleceller; PEM; bipolära plattor; katalysator; elektroplätering; korrosion; accelererad testning;

    Sammanfattning : As part of the global work towards reducing CO2 emissions, all vehicles needs to be electrified, or fueled by green fuels. Batteries have already revolutionised the car market, but fuel cells are believed to be a key energy conversion system to be able to electrify also heavy duty vehicles. LÄS MER

  4. 3. Modeling and Testing of Insulation Degradation due to Dynamic Thermal Loading of Electrical Machines

    Författare :Zhe Huang; Industriell elektroteknik och automation; []
    Nyckelord :thermal degradation; thermal cycle; dynamic temperature; thermal-mechanical; fatigue; electrical insulation system; accelerated testing; condition monitoring; electrical machine; electrified vehicles;

    Sammanfattning : Electrical machines in electrified vehicles are subjected to dynamic loadings at different driving conditions, which results in dynamic temperatures. The aging of the Electrical Insulation System (EIS) in electrical machines is caused by these dynamic temperatures, namely high average temperatures and temperature cycles. LÄS MER

  5. 4. Analyses of Resilient Behavior of Unbound Materials for the Purpose of Predicting Permanent Deformation Behavior

    Författare :Jan Englund; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Permanent Deformation; Unbound Material; Resilient Deformation; Post Compaction; Falling Weight Deflectometer FWD ; Triaxial Testing; Heavy Vehicle Simulator HVS ; Modulus;

    Sammanfattning : Post compaction is the unintended compaction of the unbound material that commences immediately after a road is brought into service and caused by densification of the material. Analogies to this post compaction can also be seen in laboratory and field tests. LÄS MER

  7. 5. Mixed-Grained Till in Pavement Structures; A Field and Laboratory Study

    Författare :Helene Kennedy; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; permanent deformation behaviour; triaxial test; pavement; till;

    Sammanfattning : The road network in Sweden has historically been constructed using rock fill and natural gravel. More than 75 per cent of the land surface of Sweden is covered by glacial till and greater utilization of site-won material will not only reduce transportation costs but will also promote better sustainability of natural assets. LÄS MER