Earth–ionosphere waveguide

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This study examines lightning activity from 2012 to 2023 around tall structures situated across diverse geographic settings based on data from the World Wide Lightning Location Network (WWLLN), with the aim of providing a global perspective on lightning incidence in their vicinity. Lightning stroke density was calculated within a 2 km radius of each structure and compared with that in a surrounding annular region extending from 2 to 10 km, enabling the identification of potential local enhancements in light

With the continued expansion of renewable energy production, the size and density of wind farms have increased by more than 50 percent since the 2000s. This growth poses challenges for reliably detecting and locating lightning strikes within wind parks. Conventional lightning location systems may lack the spatial accuracy required to uniquely identify the struck turbine, and further miss some discharges altogether when return-stroke components are absent or too weak to be detected. At the same time, approac

Integrated photonics started to surpass their traditional applications in tele- and datacommunication towards a variety of new domains including health care, artificial intelligence, and quantum applications. With this diversification, also the need for general-purpose solutions - similar to field programmable gate arrays (FPGAs) - grows, to enable for fast prototyping and lower the time and costs required for the development of new integrated photonic devices. A waveguide mesh consisting of tunable phase s

We study the effects of disorder on the coupling strength of coupled photonic crystal slab cavities by considering fully-3D electromagnetic calculations. Specifically, we investigate two coupled L3 cavities at 30 degrees and 60 degrees configurations, wher ...

The paper presents a method to identify the location of direct lightning strikes to overhead transmission lines and potential subsequent flashover(s). The method is based on the electromagnetic time reversal theory and relies on the use of a single measure ...

Complete electric and magnetic field solutions of an overhead conductor above a lossy earth are derived in this letter, and “mode transition” from a low-frequency quasi-transverse electromagnetic (TEM) to a high-frequency transverse Magnetic (TM) mode has ...

We study the nonequilibrium exciton-polariton condensation in 1D to 0D and 1D to quasi-2D junctions by means of non-resonant spectroscopy. The shape of our potential landscape allows to probe the resonant transmission of a propagating condensate between a ...

An ideal photonic integrated circuit for nonlinear photonic applications requires high optical nonlinearities and low loss. This work demonstrates a heterogeneous platform by bonding lithium niobate (LN) thin films onto a silicon nitride (Si3N4) waveguide ...

In this technical report we apply the Continuation Multi Level Monte Carlo (C-MLMC) algorithm to efficiently propagate operating and geometric uncertainties in internal and external aerodynamic simulations modeled by RANS. In particular, we discuss the construction of suitable mesh hierarchies and test the C-MLMC algorithm on the 2D RAE-2822 transonic airfoil and the 3D NASA Rotor 37 affected by operating uncertainties

Hydraulic machines operating in a wider range are subjected to cavitation developments inducing undesirable pressure pulsations which could lead to potential instability of the power plant. The occurrence of pulsating cavitation volumes in the runner and t ...

The electromagnetic field transmitted by a subwavelength circular aperture in a perfectly conducting screen of infinitesimal thickness and illuminated by an obliquely incident plane wave is analyzed based on the Bethe-Bouwkamp quasi-static model of the field in the aperture plane. The problem is formulated in the spectral domain and the solution is expressed in terms of a minimum number of one-dimensional Hankel-transform integrals involving products of Bessel functions and spherical Bessel functions. An ef

The present investigation is concerned with wave propagation in micropolar thermoelastic solid half space with distinct conductive and thermodynamic temperatures. Reflection of plane waves incident obliquely at the free surface of micropolar generalized th ...

Earth–ionosphere waveguide

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A Global Overview of Lightning Near Tall Structures

Optimal Placement of Magnetic Direction Finders for Locating Lightning-Struck Wind Turbines

Sputtered AlN on SiO2 for monolithic integrated piezoelectric photonics

Disorder effects on the coupling strength of coupled photonic crystal slab cavities

Locating lightning strikes and flashovers along overhead power transmission lines using electromagnetic time reversal

Frequency Response of Electric and Magnetic Fields of Overhead Conductors With Particular Reference to Axial Electric Field

Exciton-polariton flows in cross-dimensional junctions

Heterogeneous integration of lithium niobate and silicon nitride waveguides for wafer-scale photonic integrated circuits on silicon

MATHICSE Technical Report : Continuation Multi-Level Monte-Carlo method for Uncertainty Quantification in Turbulent Compressible Aerodynamics Problems modeled by RANS

Experimental investigation of the local wave speed in a draft tube with cavitation vortex rope

On the Plane Wave-Excited Subwavelength Circular Aperture in a Thin Perfectly Conducting Flat Screen

Effect Of Distinct Conductive And Thermodynamic Temperatures On The Reflection Of Plane Waves In Micropolar Elastic Half-Space