Sökning: "flight"

Visar resultat 1 - 5 av 501 avhandlingar innehållade ordet 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

3. 2. Escape flight in butterflies

   Författare :Maria Almbro; Cecilia Kullberg; Ronald Rutowski; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Flight; Lepidoptera; gamete load; lipid accumulation; predation risk; hibernation; Biology; Biologi; zoologi; Zoology;

   Sammanfattning : Flight is considered to be the overarching reason for the enormous diversity and world-wide abundance of insects. Not only does flight enable great distances to be covered and new areas to be colonised, flying has also evolved to be important in most adult life-history characteristics from reproduction to anti-predator strategies. LÄS MER

4. 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

5. 4. Go with the flow : visually mediated flight control in bumblebees

   Författare :Nellie Linander; Funktionell zoologi; []
   Nyckelord :insect; vision; Bombus terrestris; flight control; optic flow; centring; flight speed; height; viewing angle; learning flight; Insect; vision; Bombus terrestris; flight control; optic flow; centring; flight speed; height; viewing angle; learning flight;

   Sammanfattning : Despite their small brains and tiny eyes, flying insects are capable of detecting and avoiding collisions with moving obstacles, and with remarkable precision they navigate through environments of different complexity. For this thesis, I have investigated how bumblebees use the pattern of apparent image motion that is generated in their eyes as they move through the world (known as optic flow), in order to control flight. LÄS MER

7. 5. 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