Results 31 to 40 of about 4,282 (222)

A New GIS-Based Algorithm to Support Initial Transmitter Layout Design in Open-Pit Mines

Energies, 2018
In this paper, a new geographic information systems (GIS)-based algorithm is proposed for supporting the initial design of a wireless communications system in open-pit mines.
Jieun Baek, Yosoon Choi
doaj   +1 more source

On the Design of Soret Zone Plates Based on Binary Sequences Using Directional Transducers

Sensors, 2021
In this work, we analyze the effect of the distribution of transparent Fresnel regions over the focusing profile of Soret Zone Plates (SZP) based on binary sequences. It is shown that this effect becomes very significant in those fields where directional
Pilar Candelas, Sergio Pérez-López, José Miguel Fuster   +2 more
doaj   +1 more source

ACCOUNTING FOR SPHERISITY OF PHASE WAVE FRONTS IN THE THEORY OF WAVE SCATTERING BY TURBULENT ATMOSPHERE

Radio Physics and Radio Astronomy, 2014
For the case of wave scattering by turbulent atmosphere, the asymtotics of three-fold integrals that determine the intensity of the scattered field are found.
A. S. Bryukhovetski
doaj   +1 more source

ESTIMATION THE LOCATION PARAMETERS IN MOTION OF RADIO EMISSION SOURCE OF ELECTROMAGNETIC WAVE’S SPHERICAL FRONT

Information and Telecommunication Sciences, 2017
Background. Modern methods for determining the position of the source of radio emission in the Fresnel zone from the sphericity of the electromagnetic wave front received by the linear antenna array allow solving the problem of simultaneous determination
Evgeniy Yakornov, Oleg Tsukanov
doaj   +1 more source

Um experimento simples usado na produção de placas de zonas de Fresnel

Revista Brasileira de Ensino de Física
Neste trabalho propomos um experimento simples que tem por finalidade auxiliar no aprendizado dos fenômenos de interferência e difração da luz. Após uma análise pertinente da teoria de Fresnel da difração, os conhecimentos são aplicados na compreensão do
Márcia Muller, Jean Carlos Cardozo da Silva, José Luís Fabris   +2 more
doaj   +1 more source

Sub-wavelength lateral detection of tissue-approximating masses using an ultrasonic metamaterial lens

Nature Communications, 2020
Traditional methods for ultrasound detection in biomedical application suffer from limited lateral resolution. Here, the authors show that a phononic metamaterial lens can be used for spatial characterisation of subwavelength objects, even beyond the ...
Ezekiel L. Walker, Yuqi Jin, Delfino Reyes, Arup Neogi   +3 more
doaj   +1 more source

Security augmentation grounded on Fresnel and Arnold transforms using hybrid chaotic structured phase mask

IET Image Processing, 2021
A novel asymmetric double image encryption technique is introduced to protect the algorithm from the interlopers by using hybrid chaotic structured phase masks in Arnold and Fresnel transforms.
Shivani Yadav, Hukum Singh
doaj   +1 more source

Image reconstruction algorithms for the microwave holographic vision system with reliable gap detection at theoretical limits

EPJ Web of Conferences, 2018
We present a reliable image reconstruction algorithm suitable for a microwave holographic vision system with several sensors coupled to the spin-diode based microwave detector and a single emission source.
Leshchiner Dmitry, Zvezdin Konstantin, Popkov Anatoly, Chepkov Grigory, Perlo Pietro   +4 more
doaj   +1 more source

An achromatic X-ray lens

Nature Communications, 2022
X-ray diffractive and refractive optical elements suffer from chromatic aberrations, limiting high-resolution X-ray microscopes mainly to bright synchrotron sources.
Adam Kubec, Marie-Christine Zdora, Umut T. Sanli, Ana Diaz, Joan Vila-Comamala, Christian David   +5 more
doaj   +1 more source

Three‐dimensional Antimony Sulfide Based Flat Optics

Advanced Functional Materials, EarlyView.
This work presents the development of a grayscale electron beam lithography (g‐EBL) method for fabricating antimony trisulfide (Sb2S3) nanostructures with customizable 3D profiles. The refractive index of g‐EBL patterned Sb2S3 is determined based on the synergy of genetic algorithm and transfer matrix method.
Wei Wang, Uwe Hübner, Anne Gärtner, Tao Chen, Joseph Köbel, Franka Jahn, Daniel Repp, Abhrodeep Dey, Henrik Schneidwind, Andrea Dellith, Jan Dellith, Torsten Wieduwilt, Matthias Zeisberger, Tanveer Ahmed Shaik, Astrid Bingel, Markus A. Schmidt, Jer‐Shing Huang, Ulf Peschel, Volker Deckert   +18 more
wiley   +1 more source