Sökning: "Tolerance to damage"

Visar resultat 1 - 5 av 85 avhandlingar innehållade orden Tolerance to damage.

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. 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

5. 4. 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

7. 5. Life History and Tolerance and Resistance against Herbivores in Natural Populations of Arabidopsis thaliana

   Författare :Reiko Akiyama; Jon Ågren; Arjen Biere; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Arabidopsis thaliana; life history evolution; flowering time; germination; phenology; plant-herbivore interactions; natural selection; tolerance to leaf damage; resistance to herbivory; Plutella xylostella; Mamestra brassicae; Biology with specialization in Ecological Botany; Biologi med inriktning mot ekologisk botanik;

   Sammanfattning : In this thesis, I combined observational studies with field and greenhouse experiments to examine selection on life history traits and variation in tolerance and resistance against herbivores in natural populations of the annual herb Arabidopsis thaliana in its native range. I investigated (1) phenotypic selection on flowering time and plant size, (2) the effects of timing of germination on plant fitness, (3) the effect of leaf damage on seed production, and (4) correlations between resistance against a specialist and a generalist insect herbivore. LÄS MER