Results 91 to 100 of about 1,176,775 (247)

Axial Spacing Effects on Rotor-Rotor Interaction Noise and Vibration in a Contra-Rotating Fan

International Journal of Aerospace Engineering, 2019
Because of the potential technical advantages, the contra-rotation technology has become a renewed interest in aviation and other applications. Contra-rotation increases efficiency in comparison with the single-rotor design, but this advantage is not ...
Hengxuan Luan, Liyuan Weng, Ranhui Liu, Dongmin Li, Mingwei Wang   +4 more
doaj   +1 more source

Robotics for Crop Pollination: Recent Advances and Future Direction

Journal of Field Robotics, EarlyView.
ABSTRACT There is great interest in alternative pollination strategies for crop production in the face of climate change and perennial threats to the traditional pollination mechanisms. This review explores the potential of robotic pollination as a promising solution to these challenges affecting crop fertilization, agricultural sustainability, and ...
Ranjan Sapkota, Matthew D. Whiting, Dawood Ahmed, Manoj Karkee   +3 more
wiley   +1 more source

Accounting for animal movement during aerial imaging surveys

Remote Sensing in Ecology and Conservation, EarlyView.
Animals are not stationary during aerial surveys; if their movements are related to the movement of the aerial platform, then bias can be introduced into subsequent population count estimates. We sought to establish a framework for assessing the impacts of animal movement on count error and platform bias by comparing aggregated counts and relative ...
Rowan L. Converse, Christopher D. Lippitt, Steven E. Sesnie, David R. Stewart, Matthew J. Butler, Grant M. Harris   +5 more
wiley   +1 more source

Resource reallocation across successive systemic innovations: How Rolls‐Royce shaped the evolution of the turbojet, turboprop, and turbofan

Strategic Management Journal, EarlyView.
Abstract Research Summary Despite the importance of resource reallocation in shaping a variety of strategic outcomes, strategy scholars have paid only limited attention to the processes by which firms reallocate their resources across successive systemic innovations.
Gino Cattani, Mariano Mastrogiorgio, Giuseppe Carignani   +2 more
wiley   +1 more source

Smart Blade Count Selection to Align Modal Propagation Angle with Stator Stagger Angle for Low-Noise Ducted Fan Designs

Aerospace
The rotor–stator interaction noise is a major source of fan noise. Especially for low-speed fan stages, the tonal component is typically a dominant noise source.
Stephen Schade, Robert Jaron, Lukas Klähn, Antoine Moreau   +3 more
doaj   +1 more source

Development of an Active Flap Rotor Model [PDF]

, 2004
The research organizations ONERA and DLR initiated a common programme supported by Eurocopter (EC) and Eurocopter Deutschland (ECD) as industry partners within the Active Blade Concept (ABC).
Höfinger, Marc T., Leconte, Philippe
core  

Vibrational Exfoliation of 2D Materials

Small, EarlyView.
Vibrational energy folds, fractures and exfoliates atomically and molecularly thin materials. Combining experimentation and computational methods, this unique vibrational synthesis pathway is revealed. This process overcomes barriers of existing approaches by processing 1000 g/L dispersions without loss in yield.
Aadam Rabani, Faysal A. Khaleel, Fahad S. Al‐Gburi, Irwing Ramirez, Tomislav Friščić, Jason Stafford   +5 more
wiley   +1 more source

Rounded Monodisperse Fluorescent Nanodiamonds

Small, EarlyView.
Nanodiamond (ND) shape control using rapid molten‐nitrate etching is studied as a scale‐up method for monodispersed rounded particles. Optimal etching condition (567°C for 6 min) yields NDs with atomically stepped surfaces and reduced sp2 content. Compared to angular control, rounded NDs exhibit an increased proportion of luminescent particles (66% vs.
Helena Raabova, Ivan Rehor, Jan Havlik, Stuart Turner, Jan Stursa, Vladimira Petrakova, Michal Gulka, Petr Cigler   +7 more
wiley   +1 more source

Optimal rotor structures to reduce Windage Loss and their impact on Acoustic Noise and Vibration in Switched Reluctance Motors: Application to L5M and L5N electric-three wheelers

Ain Shams Engineering Journal
Two Switched Reluctance Motors (SRMs) rated to 3 kW and 6 kW have been designed for L5M and L5N (High-speed passenger and cargo) electric three-wheeler traction application.
Arjun Seshadri, Rahul Roy, Lenin Natesan Chokkalingam   +2 more
doaj   +1 more source

Characterization of the Pore Environments in Covalent Organic Frameworks by Dynamic Spin Probe Exchange

Small, EarlyView.
Covalent organic frameworks (COFs) with alkyl or triethylene glycol pore linings are probed with water‐dissolved nitroxide radicals using CW EPR spectroscopy. Adsorption affinity, local polarity, and radical concentration inside the pores are quantified, revealing hydrogen bonding, dipolar, and π‐π interactions that govern guest binding, which ...
Sebastian Michler, Simona Bassoli, Luisa Voigt, Makhily Diaby, Dariush Hinderberger, Frederik Haase   +5 more
wiley   +1 more source