Results 41 to 50 of about 928,348 (261)

Similarity hypotheses for the atmospheric surface layer expressed by non-dimensional characteristic invariants - a review [PDF]

, 2009
In this paper, similarity hypotheses for the atmospheric surface layer (ASL) are reviewed using nondimensional characteristic invariants, referred to as π -numbers.
Herbert, Fritz, Kramm, Gerhard
core   +1 more source

Rossby number similarity of an atmospheric RANS model using limited-length-scale turbulence closures extended to unstable stratification [PDF]

Wind Energy Science, 2020
The design of wind turbines and wind farms can be improved by increasing the accuracy of the inflow models representing the atmospheric boundary layer.
M. P. van der Laan, M. Kelly, R. Floors, A. Peña   +3 more
doaj   +1 more source

The energy- and flux budget theory for surface layers in atmospheric convective and stably stratified turbulence [PDF]

, 2022
The energy- and flux budget (EFB) turbulence closure theory for the atmospheric surface layers in convective and stably stratified turbulence has been developed using budget equations for turbulent energies and fluxes in the Boussinesq approximation.
Zilitinkevich, S., I. Rogachevskii, Zilitinkevich, Sergej, Kleeorin, N., Rogachevskii, Igor,, Kleeorin, Nathan,, Rogachevskii, I., S. Zilitinkevich, N. Kleeorin, Zilitinkevich, S.,   +9 more
core   +1 more source

Modulation Transfer Function of a Gaussian Beam Based on the Generalized Modified Atmospheric Spectrum

International Journal of Optics, 2016
This paper investigates the modulation transfer function of a Gaussian beam propagating through a horizontal path in weak-fluctuation non-Kolmogorov turbulence. Mathematical expressions are obtained based on the generalized modified atmospheric spectrum,
Chao Gao, Xiaofeng Li
doaj   +1 more source

Performance analysis of optical wireless communications with aperture averaging over exponentiated Weibull turbulence with pointing errors

Results in Optics, 2021
Aperture averaging (AA) is a potential technique to reduce the effect of atmospheric turbulence in optical wireless communications (OWC). Although there is significant research on point-like detectors, there is a gap in the study on the analytical ...
Ziyaur Rahman, Syed Mohammad Zafaruddin, Vinod Kumar Chaubey   +2 more
doaj   +1 more source

Evolution Properties of a Partially Coherent Twisted Laguerre-Gaussian Pulsed Beam Propagating through Anisotropic Atmospheric Turbulence

Photonics, 2022
Analytical expressions for the cross-spectral density matrix of a partially coherent twisted Laguerre-Gaussian pulsed (PCTLGP) beam in anisotropic atmospheric turbulence are derived based on the extended Huygens–Fresnel principle.
Ying Xu, Yonggen Xu, Tiejun Wang
doaj   +1 more source

Experimental investigation of the performance of different modulation techniques under controlled FSO turbulence channel [PDF]

, 2010
This paper experimentally investigates and compares the performance of the free space optics system employing three different modulation schemes, on-off keying (OOK) with nonreturn- to-zero (NRZ) and return-to-zero (RZ) and the binary phase shift keying (
Z. Ghassemlooy, Adebanjo, Olusegun, O. Adebanjo, S. Ansari, S. Rajbhandari, Ghassemlooy, Zabih, H. Le Minh, Ansari, S., A. Gholami, Rajbhandari, Sujan, Ijaz, Muhammad, M. Ijaz, Le Minh, Hoa   +12 more
core   +1 more source

Breaking the Surface: Buoyant Metal–Polymer Open–Cell Hybrid Lattice Metamaterials

Advanced Materials, EarlyView.
Open‐cell metal–polymer lattice metamaterials that defy sinking. (a) Injection process of the polyurethane (PU) foam into the titanium (Ti‐6Al‐4V) hollow‐strut lattice creating the open‐cell Ti‐6Al‐4V+PU hybrid lattice, (b) flotation test of a hybrid lattice specimen, and (c) a digital representation and experimental validation of a marine buoy ...
Jordan Noronha, Joey Tallon, Raad Omar, Jason Dash, Andrey Molotnikov, Martin Leary, Milan Brandt, Ma Qian   +7 more
wiley   +1 more source

Multistep ahead atmospheric optical turbulence forecasting for free-space optical communication using empirical mode decomposition and LSTM-based sequence-to-sequence learning

Frontiers in Physics, 2023
Although free-space optical communication (FSOC) is a promising means of high data rate satellite-to-ground communication, beam distortion caused by atmospheric optical turbulence remains a major challenge for its engineering applications.
Yalin Li, Hongqun Zhang, Lang Li, Lang Li, Lang Li, Lu Shi, Lu Shi, Yan Huang, Shiyao Fu, Shiyao Fu, Shiyao Fu   +10 more
doaj   +1 more source

From Lab to Landscape: Environmental Biohybrid Robotics for Ecological Futures

Advanced Robotics Research, EarlyView.
This Perspective explores environmental biohybrid robotics, integrating living tissues, microorganisms, and insects for operation in real‐world ecosystems. It traces the leap from laboratory experiments to forests, wetlands, and urban environments and discusses key challenges, development pathways, and opportunities for ecological monitoring and ...
Miriam Filippi
wiley   +1 more source