Numerical Modeling, Trim, and Linearization of a Side-by-Side Helicopter in Hovering Conditions by Francesco Mazzeo, Marilena D. Pavel, Daniele Fattizzo, Emanuele L. de Angelis, Fabrizio Giulietti

“…The analysis showed that non-uniform inflow modeling led to a coupled longitudinal inflow–phugoid mode which made the vehicle prone to dangerous instabilities. …”
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COMPUTATIONAL STUDY OF AERODYNAMIC CHARACTERISTICS OF SINGLE-ROTOR HELICOPTER TAIL ROTOR UNDER THE INFLUENCE OF VORTICAL WAKE OF MAIN ROTOR AT THE HOVER WITH CROSSWIND by Yu. M. Ignatkin, P. V. Makeev, A. I. Shomov, V. A. Ivchin

“…The modelling has been made on the base of non-linear blade (free wake) vortical model of rotor, produced at Helicopter Design Department of MAI.Helicopter hovering modes with crosswind of various intensity Vz was considered. …”
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Reliability assessment of convertible aircraft with hybrid propulsion system and multirotor lifting system by A. V. Redkin, Yu. A. Yaloza, I. E. Kovalev

“…The article discusses the influence of the number of lifting rotor groups and their location on the possibility to continue the flight in hover mode in case of failure of one rotor group, the necessary power reserve of lifting electric motors is determined to ensure the given safety condition. …”
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Extracting Vehicle Trajectories Using Unmanned Aerial Vehicles in Congested Traffic Conditions by Eui-Jin Kim, Ho-Chul Park, Seung-Woo Ham, Seung-Young Kho, Dong-Kyu Kim

“…Unmanned aerial vehicles (UAVs), with incorporating machine learning and image processing, can mitigate these difficulties by their ability to hover above the traffic. However, research is lacking regarding the extraction and evaluation of vehicle trajectories in congested traffic. …”
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Quantifying the Bicycle Share Gender Gap by Kate Hosford, Meghan Winters

“…The proportion of trips made by women increased over time for Citi Bike from 22.6% in 2014 to 25.5% in 2018, but hovered steady around 25% for Bluebikes and Divvy Bikes. …”
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Crowd-sourcing higher education architecting the sustainable design and development of E-Learning in Africa by Griff Richards

“…Post-secondary access in Africa hovers around 6%, in part because there is a lack of access to physical campuses. …”
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An Efficient Approach for Modeling and Control of a Quadrotor by Ahmed S. Khusheef

“…  A quadrotor is a four-rotor aircraft capable of vertical take-off and landing, hovering, forward flight, and having great maneuverability. …”
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Chaos bound and its violation in black p-brane by Pinaki Dutta, Kamal L. Panigrahi, Balbeer Singh

“…Similar observations were made for the classical string, where the violation of the bound is significant near the horizon. …”
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JDP Network 1999/2009/2019: A Living History of John Durham Peters’ Historiography by Jeremy Packer

“…Friedrich Kittler guides JDP 2009. Harold Innis hovers, Google Earth-like, above JDP 2019. The dominant forms of historical evidence are also fundamentally different. …”
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Finite Time Adaptive SMC for UAV Trajectory Tracking Under Unknown Disturbances and Actuators Constraints by Khelil Sidi Brahim, Ahmed El Hajjaji, Nadjiba Terki, David Lara Alabazares

“…A new adaptive sliding mode control (ASMC) with finite-time convergence characteristics is proposed to guarantee quadrotor hovering in spite of parametric uncertainties and external disturbances. …”
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