Sökning: "swimming velocity"

Visar resultat 1 - 5 av 13 avhandlingar innehållade orden swimming velocity.

  1. 1. Morphological antipredator adaptations in water fleas

    Författare :Hans Lord; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Body drag; Daphnia cristata; Reynolds number; viscosity; zooplankton; Bosmina; swimming velocity; cyclomorphosis; sexual dimorphism; head area; helmet angle; trophic condition; allometry; invertebrate predator; fish;

    Sammanfattning : Some Bosmina and Daphnia species have the ability to develop extreme morphological antipredator defences, such as long antennules, high carapaces and helmets. The relative sizes of these plastic traits may differ substantially between populations, and also between individuals within a population, between sexes and during ontogeny. LÄS MER

  3. 2. Simulation of individual cells in flow

    Författare :Lailai Zhu; Luca Brandt; Michael Graham; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hydrodynamic interaction; swimming microorganisms; capsule; Stokes flow; finite element method; boundary integral method; general geometry Ewald method; spectral element method; viscoelastic fluid; cellular deformation; flow cytometry; cell sorting; microrheology; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : In this thesis, simulations are performed to study the motion ofindividual cells in flow, focusing on the hydrodynamics of actively swimming cells likethe self-propelling microorganisms, and of passively advected objects like the red bloodcells. In particular, we develop numerical tools to address the locomotion ofmicroswimmers in viscoelastic fluids and complex geometries, as well as the motion ofdeformable capsules in micro-fluidic flows. LÄS MER

  4. 3. Flow design for migrating fish

    Författare :Elianne Lindmark; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningslära; Fluid Mechanics;

    Sammanfattning : The utilization of rivers for hydropower production leads to problems for migrating fish, such as Atlantic salmon (Salmo salar) and sea trout (Salmo trutta). Both salmon and trout reproduce in fresh water, but spend their adult years at sea. To overcome man-made obstructions to and from the spawning grounds the fish needs help. LÄS MER

  5. 4. Simulation of collective phenomena in microswimmer suspensions

    Författare :Dora Bardfalvy; Fysikalisk kemi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Collective motion is ubiquitous in biological and synthetic systems across manylength- and timescales. On the macroscopic scale, examples include schools of fish, herds of sheep and flocks of birds. On the microscopic scale, bacteria, algae and synthetic self-propelled particles exhibit a range of collective phenomena. LÄS MER

  7. 5. Phenotypic plasticity and the evolution of an inducible morphological defence in crucian carp

    Författare :Lars Pettersson; Biodiversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Animal ecology; Benefits; Costs; Predation; Chemical cues; Fish; Djurekologi;

    Sammanfattning : In this thesis, I have investigated factors (cues, benefits, and costs) affecting the evolution of an inducible morphological defence in crucian carp (Carassius carassius). Inducible defences are favoured over permanent defences when prey have reliable cues to detect predators, when defences are effective but costly, and when predation pressure is variable and unpredictable, but sometimes strong. LÄS MER