Avancerad sökning

Visar resultat 1 - 5 av 813 avhandlingar som matchar ovanstående sökkriterier.

1. 1. The Plasma Contact System : New Functional Insights from a Hemostatic and Thrombotic Perspective

   Författare :Jennie Bäck; Bo Nilsson; Kristina Nilsson Ekdahl; Ulla Hedner; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Contact activation; factor XII; platelets; coagulation; antithrombin; C1 inhibitor; hemostasis; biomarkers; vascular disease.; Klinisk immunologi; Clinical Immunology;

   Sammanfattning : The physiological role of the plasma contact system still remains a partial enigma. The aim of the presented work was to expand our understanding of the plasma contact system, focusing on its physiological activation and function, principally from a hemostatic perspective. It also explored contact system activation under pathological conditions. LÄS MER

3. 2. Accuracy, efficiency and robustness for rigid particle simulations in Stokes flow

   Författare :Anna Broms; Anna-Karin Tornberg; Mattias Sandberg; Eric Keaveny; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Stokes flow; rigid particles; accuracy; fundamental solutions; method of images; multiblob; contact avoiding; complementarity problem; barrier method; elliptic PDE; grid optimisation; pair-correction; boundary integral equations; Stokesflöde; noggrannhet; stela partiklar; fundamentallösningar; randintegralekvation; reflektionspunkter; multiblob; kontaktundvikande algoritmer; komplementaritetsproblem; barriärmetod; elliptisk PDE; gridoptimering; parkorrektion; Numerical Analysis; Numerisk analys;

   Sammanfattning : The thesis concerns simulation techniques for systems of nano- to micro-scaled rigid particles immersed in a viscous fluid, ubiquitous in nature and industry. With negligible fluid inertia, the set of PDEs known as the Stokes equations can be used to model the hydrodynamics. LÄS MER

4. 3. Wavelet Galerkin methods for elastic multibody systems with unilateral contact constraints

   Författare :José Díaz López; Matematik LTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Computer science; Elastic MBS; Contact; Unilateral Contraints; Wavelet; DAE; Daubechies; numerical analysis; systems; control; Datalogi; numerisk analys; system; kontroll;

   Sammanfattning : In this thesis we investigate the applicability of wavelets to simulate the time behavior of elastic multibody systems (MBS) with contact constraints. For this end, a wavelet element method (WEM) was implemented, exploiting the special structure of the coupled ODE/PDE equations that govern elastic MBS. LÄS MER

5. 4. Speciation and Metabolic rate : Insights from an avian hybrid zone

   Författare :S. Eryn McFarlane; Anna Qvarnström; Jenny Boughman; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; resting metabolic rate; life history; hybridization; speciation; reproductive isolation; Ficedula flycatcher; Biologi med inriktning mot zooekologi; Biology with specialization in Animal Ecology;

   Sammanfattning : The role of divergent climate adaptation in speciation has received surprisingly little scientific attention. My dissertation research focused on how resting metabolic rate (RMR) relates to the build up of prezygotic and postzygotic isolation in a natural Ficedula flycatcher hybrid zone. LÄS MER

7. 5. Wheel-rail contact modelling in vehicle dynamics simulation

   Författare :Matin Shahzamanian Sichani; Mats Berg; Roger Enblom; Elena Kabo; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wheel-rail contact; non-elliptic contact; vehicle-track interaction; rail vehicle dynamics; rolling contact; MBS; virtual penetration; Järnvägsgruppen - Fordonsteknik; Järnvägsgruppen - Fordonsteknik; Järnvägsgruppen - Tribologi; The KTH Railway Group - Tribology;

   Sammanfattning : The wheel-rail contact is at the core of all research related to vehicle-track interaction. This tiny interface governs the dynamic performance of rail vehicles through the loads it transmits and, like any high stress concentration zone, it is subjected to serious damage phenomena. LÄS MER