Sökning: "bird flight"

Visar resultat 1 - 5 av 23 avhandlingar innehållade orden bird flight.

  1. 1. Birds in the Flow: Flight Mechanics, Wake Dynamics and Flight Performance

    Författare :Mikael Rosén; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Djurekologi; Animal ecology; Eleonora s falcon.; hunting; optimum wingspan; tail posture; wingbeat kinematics; wake topology; DPIV; flight performance; wake dynamics; flight mechanics; wind tunnel; Flight; bird;

    Sammanfattning : I share my fascination of bird flight with many others, and here I summarise my thesis on the subject. This thesis emphasises the mechanics of bird flight by focusing on flight mechanics, wake dynamics and flight performance. LÄS MER

  2. 2. Feathers by day, membranes by night - Aerodynamic performance in bird and bat flight

    Författare :Florian Muijres; Evolutionär ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; animal flight; aerodynamics; vortex wake; actuator disk; flight performance; span efficiency; bird; bat; wind tunnel; PIV; Pied Flycatcher; Glossophaga soricina; Leptonycteris yerbabuenae;

    Sammanfattning : The efficiency and performance of a flying animal is directly related to the aerodynamics around its body and flapping wings. Here, I have developed methods for quantifying the wake dynamics around a flying animal. The results are used to estimate the aerodynamic performance of flapping flight. LÄS MER

  3. 3. Flight Behaviour of Passerines on Nocturnal Migration

    Författare :Cecilia Nilsson; Evolutionär ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bird migration; Passerines; Flight Behaviour; Tracking radar; Optimal migration; Flight speed; Airspeed; Wind drift; Nocturnal migration; Coastline effects; Flight directions; Reverse migration;

    Sammanfattning : Many passerines migrate during the night and at high altitudes, making their migration difficult to observe. By using tracking radars we have been able to make exact observations of the flight behaviour of passerines on nocturnal migration, which has enabled us to test several hypotheses about adaptive values and constraints regarding migratory behaviour in different ecological contexts. LÄS MER

  4. 4. In the wake of a bird - Quantifying aerodynamic performance of avian flight

    Författare :Marco Klein Heerenbrink; Evolutionär ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; animal flight; flight performance; gliding; powered flight; wing morphology; aerodynamics; biomechanics; birds; jackdaw; Corvus monedula; wind tunnel; PIV;

    Sammanfattning : Flight is an expensive form of locomotion, but also offers the ability to travel great distances at relatively low cost. Birds have developed various adaptations for optimizing flight performance. The main aim of this thesis is to identify how morphological variables in birds affect aerodynamic drag and flight performance. LÄS MER

  5. 5. Flight strategies in migrating birds: when and how to fly

    Författare :Martin Green; Biodiversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; geese; waders; terns; Animal ecology; Djurekologi; wind tunnel; radio telemetry; satellite telemetry; radar; formation flight; flight speed adjustment; wind drift; energy savings; departure decisions; bird migration; wind;

    Sammanfattning : Wind has a profound influence on migrating birds since it inevitably will influence travel time and energy expenditure. In this thesis I investigate how migrating birds are affected by, and use winds. LÄS MER