Results 41 to 50 of about 92,623 (181)
Ground zero soil sampling: Trinity, 1945
Geology Today, Volume 41, Issue 4, Page 137-146, July/August 2025.At Trinity—the world's first nuclear weapons testing site—large quantities of soil were drawn into the fireball to redeposit either downwind as radioactive fallout or in the near‐field as a unique, anthropogenic silicate glass trinitite. Manhattan Project physicists and chemists came to see soils at the Trinity site as a useful medium to assess the ...
Edward R. Landa
wiley +1 more source
Научный вестник МГТУ ГАA coaxial main rotor (MR), consisting of upper (UR) and lower (LR) rotors with a spacing of planes and a different direction of rotation, has a number of advantages in aerodynamic characteristics compared to an equivalent single rotor of the same radius,
P. V. Makeev
doaj +1 more source
Wind Tunnel Studies on Hover and Forward Flight Performances of a Coaxial Rigid Rotor
Aerospace, 2021 The aerodynamic performance of a reduced-scale coaxial rigid rotor system in hover and steady forward flights was experimentally investigated to gain insights into the effect of interference between upper and lower rotors and the influences of the ...
Chang Wang +5 more
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A Review of Modeling and Control Techniques for Unmanned Aerial Vehicles
Engineering Reports, Volume 7, Issue 6, June 2025.By systematically classifying UAV modeling techniques and comparing control methods, this paper addresses a notable gap in the current literature. Furthermore, it highlights emerging trends and challenges in UAV control systems, providing valuable insights to guide future research toward enhancing the stability, efficiency, and adaptability of ...
Elisabeth Andarge Gedefaw +2 more
wiley +1 more source
Numerical Study of Coaxial Main Rotor Aerodynamics in Steep Descent
Aerospace, 2022 Numerical studies of the aerodynamic characteristics of the coaxial main rotor of the Kamov Ka-32 helicopter in steep descent modes, including the area of the vortex ring state (VRS) modes, have been performed.
Pavel Makeev +2 more
doaj +1 more source
Jixie chuandong, 2022 The rotor shaft vibration of the helicopter transmission system is an important factor affecting its operational reliability. In order to improve the safety margin of torsional vibration of the rotor shaft system of a coaxial counter-rotating double ...
De Ni +4 more
doaj
Emerging Trends in Bioinspired Superhydrophobic and Superoleophobic Sustainable Surfaces
Advanced Materials, Volume 37, Issue 12, March 26, 2025.Biomimicry offers an exceptional opportunity to design materials with advanced properties. This review summarizes the latest findings for developing sustainable superhydrophobic–superoleophobic materials using biomimicry, their challenges, and future directions.
Cerys M. Cormican +3 more
wiley +1 more source
The Role of Orogenic Collapse on Tectonic Inheritance of Passive Continental Margins
Tectonics, Volume 44, Issue 1, January 2025.Abstract The break‐up and drift of continents is governed by the reactivation of structures in the lithosphere that occur in preference to formation of new structures during rifting. Numerical analyses indicate that mantle heterogeneities should be a first‐order control on tectonic inheritance; however, the importance of mantle relative to crustal ...
Jeffrey Pollock
wiley +1 more source
Conversion of a Coaxial Rotorcraft to a UAV—Lessons Learned
AerospaceA coaxial helicopter with a maximum take-off weight of 600 kg was converted to an unmanned aerial vehicle. A minimally invasive robotic actuator system was developed, which can be retrofitted onto the copilot seat of the rotorcraft in a short period of ...
Barzin Hosseini +4 more
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A Special Kind of Sliding Mode Control for Nonlinear System With State Constraints
IEEE Access, 2019 This paper presents a control strategy named auxiliary surfaces sliding mode control (AS-SMC) by using Positive Invariant Set (PIS) to control a class of continuous nonlinear systems with state constraints.
Zhi Chen +4 more
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