Results 1 to 10 of about 3,857,912 (186)
The Ground Effect in Anguilliform Swimming. [PDF]
Biomimetics (Basel), 2020 Some anguilliform swimmers such as eels and lampreys swim near the ground, which has been hypothesized to have hydrodynamic benefits. To investigate whether swimming near ground has hydrodynamics benefits, two large-eddy simulations of a self-propelled anguilliform swimmer are carried out—one swimming far away from the ground (free swimming) and the ...
Ogunka UE +3 more
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Low altitude control for quadcopter using visual feedback [PDF]
Archives of Electrical Engineering, 2021 The paper presents the results of simulations and experiments in the field of control of the low damping and time delay oscillating system. This system includes a quadcopter hovering at a very low altitude, and the altitude is controlled.
Konrad Urbański
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Aerodynamic analysis of an AK-47 bullet moving at mach 2.0 in close proximity to the ground [PDF]
FME Transactions, 2022 The bullet is shot near the wall or the ground during urban warfare. This nearness leads to a pressure distribution on the bullet's entire body, which is asymmetric.
Gholap Tanmay B. +4 more
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Influence of Aerodynamic Characteristics of Airfoil Forward Flight Considering Step-Type Ground
Shanghai Jiaotong Daxue xuebao, 2023 The aerodynamic influence of ground effects during forward flight is difficult to ignore, especially when there is a sudden change in the ground structure.
XU Xiaogang, ZHANG Yang, CHANG Min, CHEN Gang
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An AI-in-Loop Fuzzy-Control Technique for UAV’s Stabilization and Landing
IEEE Access, 2022 In this paper, an adaptable fuzzy control mechanism for an Unmanned Aerial Vehicle (UAV) to manipulate its mechanical actuators is provided. The mission (landing) for the UAV is defined to track (land on) an object that is detected by a deep learning ...
Mohammed Rabah +3 more
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Circulation Control of Airfoil Aerodynamic Force Under Ground Effect of Wavy Wall
Shanghai Jiaotong Daxue xuebao, 2022 The interaction of airflow and sea waves seriously affects the flight stability and cruising safety of ground effect vehicles. The influence of different sea states and different angles of attack were analyzed numerically on the aerodynamic ...
LIU Hao, SUN Jianhong, SUN Zhi, TAO Yang, WANG Dechen, LIU Guangyuan
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Diffraction assisted rough ground effect. [PDF]
The Journal of the Acoustical Society of America, 2010 Ground effect results from the interference between sound traveling directly from a point source to a receiver and that reflected coherently from the ground. The frequencies associated with first and subsequent order destructive interference in excess attenuation spectra are determined by the source-receiver geometry and the ground impedance. Typically
Bashir, Imran +3 more
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Research on Ground Effect of Ducted Fans of VTOL UAVs
水下无人系统学报, 2023 In recent years, ducted fans, as a kind of propeller with excellent performance, have been widely used in various vertical take-off and landing(VTOL) unmanned aerial vehicles(UAVs). However, there is less research on its ground effect in China. Therefore,
Yu ZHOU, Weizheng CHEN
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Investigation of Ground Effect on the Beamforming of the Glide Path Altitude Adjustment Navigation System [PDF]
فناوری در مهندسی هوافضا, 2021 The Glide Path altitude adjustment system is one of the tools of the landing navigation system (ILS) that helps the airplane to find its angle related to the runway by sending radio signals.
Zahra Davoodabadi farahani +2 more
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Revising of the Near Ground Helicopter Hover: The Effect of Ground Boundary Layer Development
Applied Sciences, 2021 The interaction of a helicopter rotor with the ground in hover flight is addressed numerically using a hybrid Eulerian–Lagrangian CFD model. When a helicopter takes off or lands, its wake interferes with the ground.
Theologos Andronikos +3 more
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