Results 101 to 110 of about 64,082 (287)
DronesThe flight controllability and safety of unmanned compound rotorcraft are closely related to their aerodynamic characteristics. During forward flight, complex aerodynamic interference effects arise among the rotor, propeller, wing, fuselage, and ...
Xinfan Yin +7 more
doaj +1 more source
Rotor-vortex interaction noise [PDF]
A theoretical and experimental study was conducted to develop a validated first principles analysis for predicting noise generated by helicopter main-rotor shed vortices interacting with the tail rotor.
Amiet, R. K., Schlinker, R. H.
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Wildlife Biology, EarlyView.Drones are used to monitor bird nesting sites at less accessible locations, such as on cliffs, human infrastructure, or within the tree canopy. While there are a growing number of studies documenting avian behavioral responses to various drones, there is a continued need to monitor taxa‐specific responses to different drone models. We explored both the
Natasha K. Murphy +4 more
wiley +1 more source
Performance and loads data from an outdoor hover test of a Lynx tail rotor [PDF]
A Lynx tail rotor was tested in hover at the Outdoor Aerodynamic Research Facility at NASA Ames Research Center. The test objectives were to measure the isolated rotor performance to provide a baseline for subsequent testing, and to operate the rotor ...
Hagen, Martin J. +3 more
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Cable suspended windmill [PDF]
, 1990 A windmill is disclosed which includes an airframe having an upwind end and a downwind end. The first rotor is rotatably connected to the airframe, and a generator is supported by the airframe and driven by the rotor. The airframe is supported vertically
Farmer, Moses G.
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Wildlife Biology, EarlyView.Roe deer is a species that hides their neonates as an anti‐predator strategy. This may prove efficient against mammalian predators, such as the red fox; however, it might be an ecological trap as large numbers of fawns are killed by tractors with harvesters each year during grass harvest.
Thomas Vogler +2 more
wiley +1 more source
A study of helicopter stability and control including blade dynamics [PDF]
A linearized model of rotorcraft dynamics has been developed through the use of symbolic automatic equation generating techniques. The dynamic model has been formulated in a unique way such that it can be used to analyze a variety of rotor/body coupling ...
Curtiss, H. C., Jr., Zhao, Xin
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Experimental implementation controlled SPWM inverter based harmony search algorithm [PDF]
, 2017 An optimum PI controller using harmony search optimization algorithm (HS) is utilized in this research for the single-phase bipolar SPWM inverter. The aim of this algorithm is to avoid the conventional trial and error procedure which is usually applied ...
A. F. Yahaya, Jabbar +4 more
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The performance of drones and artificial intelligence for monitoring sage‐grouse at leks
Wildlife Biology, EarlyView.Accurately monitoring sage‐grouse populations is critical for conservation, yet traditional ground‐based visual surveys face challenges in scalability and consistency, prompting the exploration of innovative drone‐based methodologies enhanced by artificial intelligence.
Lance B. McNew +2 more
wiley +1 more source
Aerodynamic interference effects on tilting proprotor aircraft [PDF]
The Green's function method was used to study tilting proprotor aircraft aerodynamics with particular application to the problem of the mutual interference of the wing-fuselage-tail-rotor wake configuration.
Ham, N. D. +3 more
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