Results 41 to 50 of about 13,840,373 (231)

The Swedish Arctic Fox Project: 40 years of research in ecology and conservation

The Journal of Wildlife Management, EarlyView.
The 4 central research themes in The Swedish Arctic Fox Project and key deliverables for practical conservation achieved over 4 decades. Abstract The scientific community widely recognizes the value of long‐term studies, especially those with individual‐level resolution; however, maintaining a consecutive data series is associated with multiple ...
Anders Angerbjörn, Julie Bommerlund, Christopher A. Cockerill, Love Dalén, Bodil Elmhagen, Rasmus Erlandsson, Malin Hasselgren, Peter Hellström, Malin Larm, Karin Norén, Magnus Tannerfeldt, Johan Wallén   +11 more
wiley   +1 more source

Numerical Investigation of Vibration Reduction Through IBC for a 20to Helicopter Rotor Model [PDF]

, 2002
This paper presents theoretical results of vibration reduction through IBC (Individual Blade Control) for a 20to helicopter rotor model which are based on numerical computations.
van der Wall, Berend G., Auspitzer, Thomas, Höfinger, Marc T., Fürst, Daniel   +3 more
core  

Experimental and field evidence indicate that islet‐nesting tundra birds experience reduced nest predation and benefit indirectly from high snow goose densities

Oikos, EarlyView.
Landscape features can shape the occurrence and strength of predator–prey interactions by influencing predation risk and prey distribution. In the High Arctic, some bird species select nesting sites with physical features that impede access for their main terrestrial predator, the Arctic fox.
Marylou Beaudoin, Andréanne Beardsell, Éliane Duchesne, Madeleine‐Zoé Corbeil‐Robitaille, Pierre Legagneux, Dominique Berteaux, Joël Bêty   +6 more
wiley   +1 more source

Influence of blade aerodynamic model on prediction of helicopter rotor aeroacoustic signatures [PDF]

, 2011
Brown’s vorticity transport model has been used to investigate how the local blade aerodynamic model influences the quality of the prediction of the high-frequency airloads associated with blade–vortex interactions, and thus the accuracy with which the ...
Kelly, Mary E., Brown, Richard
core   +3 more sources

Dynamic Modeling of a Transport Helicopter for Internal Cargo Airdrop

International Journal of Aerospace Engineering
This paper proposes a dynamic model for helicopter cargo airdrop process simulation. The overall method is used to incorporate the cargo motion into the general helicopter equations of motion, which simplified the complex cargo–helicopter contact model ...
Yihua Cao, Wensong Nie
doaj   +1 more source

Study on Helicopter Antitorque Device Based on Cross-Flow Fan Technology

International Journal of Aerospace Engineering, 2016
In order to improve low-altitude flight security of single-rotor helicopter, an experimental model of a helicopter antitorque device is developed for wind tunnel test. The model is based on the flow control technology of the cross-flow fan (CFF).
Du Siliang, Tang Zhengfei, Xu Pei, Ji Mengjiang   +3 more
doaj   +1 more source

Exploring consumer preferences for wild meat and other animal proteins in Gamba, Gabon: Implications for conservation and management of natural resources alongside extractive industry

People and Nature, EarlyView.
Abstract The town of Gamba in southwest Gabon represents an exceptional example of how the development of an extractive industry (in this case oil production) may impact wild meat consumption in an area of global importance for biodiversity. Studies in the 1990s identified an active wild meat trade; however, no studies have been undertaken since, and ...
James McNamara, Landry Tchignoumba, Gabriel Koumba, Ghislain Guissouegou, Anna Feistner   +4 more
wiley   +1 more source

Evaluating Testability of Permafrost Models Through Physical and Thermal Testing in Complex Mountain Terrain, Yukon, Canada

Permafrost and Periglacial Processes, EarlyView.
ABSTRACT Due to its subsurface nature, permafrost cannot be directly observed with the naked eye or optical remote sensing. Consequently, accurately describing its distribution and thermal state is challenging. This is especially true in vast, remote environments, where obtaining comprehensive field data is demanding or improbable.
Ria Nicholson, Philip P. Bonnaventure, Nick C. Noad, Madeleine C. Garibaldi, Rabecca Thiessen, Will Kochtitzky   +5 more
wiley   +1 more source

Optimization of helicopter and UAV coordinated SAR time

Scientific Reports
The optimization of total helicopter-unmanned aerial vehicle (UAV) coordinated search-and-rescue (SAR) time to buy time for follow-up rescue activities is an important problem in air rescue that needs to be solved. In this study, helicopter was used as a
Ming Zhang, Ying Huo, Hanzhi Zhang, Jiale Duan, Faqiang Wen   +4 more
doaj   +1 more source

Internal Structure, Kinematics, and Prehistory of Frozen Debris Lobe‐A (FDL‐A), Brooks Range, Alaska

Permafrost and Periglacial Processes, EarlyView.
ABSTRACT Frozen Debris Lobe‐A (FDL‐A)—one of hundreds of FDLs in the Brooks Range of northern Alaska—is a slow‐moving landslide in permafrost that has been the subject of research since 2008 due to its close proximity to the Dalton Highway. Here, we synthesize more than a decade's worth of climate and surface measurements of monitored FDLs, and the ...
Margaret M. Darrow, Esther L. Babcock, Ben A. Leshchinsky   +2 more
wiley   +1 more source