Sökning: "damage tolerance"

Visar resultat 1 - 5 av 86 avhandlingar innehållade orden damage tolerance.

  1. 1. Damage Tolerance of Impacted Composite Sandwich Structures

    Författare :Moeen ud din Saeed Rajput; Malin Åkermo; Stefan Hallström; Magnus Burman; Christian Berggreen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; composite sandwich; cellular; polymer; material characterization; modulus; non-crimp fabric; low velocity impact; vibration; uncertainty analysis; drop-weight impact; fractography; barely visible impact damage; X-ray microtomography; compression-after-impact; bending-after-impact; high speed image processing; damage resistance; damage tolerance; Aerospace Engineering; Flyg- och rymdteknik;

    Sammanfattning : This thesis deals with damage tolerance of impacted sandwich structures for load bearing applications. Composite sandwich structures find wide application as lightweight solutions in aerospace components, since weight reduction and less fuel emissions are primary concerns for aircraft manufactures. LÄS MER

  3. 2. Damage tolerance and residual strength of composite sandwich structures

    Författare :Peter H. Bull; KTH; []
    Nyckelord :sandwich structure; damage tolerance; carbon fiber; compression after impact;

    Sammanfattning : The exploitation of sandwich structures as a means toachieve high specific strength and stiffness is relatively new.Therefore, the knowledge of its damage tolerance is limitedcompared to other structural concepts such as truss bars andmonocoque plate solutions. Several aspects of the damage tolerance of sandwichstructures are investigated. LÄS MER

  4. 3. Failure of Sandwich Structures with Sub-Interface Damage

    Författare :Andrey Shipsha; KTH; []
    Nyckelord :sandwich structure; foam core; fatigue; crack growth; stress intensity factor; fatigue threshold; fracture toughness; damage tolerance; impact damage; crushed core; bridging; fracture analysis; point-stress criterion;

    Sammanfattning : .... LÄS MER

  5. 4. Ecology and evolution of tolerance in two cruciferous species

    Författare :Elin Boalt; Kari Lehtilä; Johan Ehrlén; Julia Koricheva; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; herbivory; tolerance; methodology; Raphanus raphanistrum; Cardamine pratensis; folivory; apex removal; plant competition; ploidy levels; herbivore pressure; Other biology; Övrig biologi; växtekologi; Plant Ecology;

    Sammanfattning : Tolerance to herbivory is the ability of plants to maintain fitness in spite of damage. The goal of this thesis is to investigate the genetic variation and expression of tolerance within species, determine whether and in what conditions tolerance has negative side-effects, and how tolerance is affected by different ecological factors. LÄS MER

  7. 5. Ischemic Tolerance and Cell Signaling in the Rat Brain

    Författare :Mehrdad Shamloo; Lund Wallenberg Neurocentrum; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; preconditioning; cell death; tyrosine phosphorylation; tolerance; ERK; Calpain; CaMKII; PKC; protection; Brain; ischemia; Neurology; neuropsychology; neurophysiology; Neurologi; neuropsykologi; neurofysiologi;

    Sammanfattning : A brief period of sublethal ischemia in the brain induces resistance to a subsequent, otherwise lethal ischemic insult. This phenomenon is known as ischemic tolerance or preconditioning. A model of ischemic preconditioning in the rat brain using the two-vessel occlusion model of global cerebral ischemia was established. LÄS MER