In this letter, a procedure for the calculation of transmission loss maps from numerical simulations in the time domain is presented. It can be generalized to arbitrary time sequences and to elastic media and provides an insight into how energy spreads into a complex configuration. In addition, time dispersion maps can be generated. These maps provide additional information on how energy is distributed over time. Transmission loss and time dispersion maps are generated at a negligible additional computational cost. To illustrate the type of transmission loss maps that can be produced by the time-domain method, the problem of the classical two-dimensional upslope wedge with a fluid bottom is addressed. The results obtained are compared to those obtained previously based on a parabolic equation. Then, for the same configuration, maps for an elastic bottom and maps for non-monochromatic signals are computed.
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Front Cell Neurosci
January 2025
Department of Anatomy, Faculty of Medicine, Masaryk University, Brno, Czechia.
Introduction: The choroid plexus is located in the cerebral ventricles. It consists of a stromal core and a single layer of cuboidal epithelial cells that forms the blood-cerebrospinal barrier. The main function of the choroid plexus is to produce cerebrospinal fluid.
View Article and Find Full Text PDFBMC Plant Biol
January 2025
CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, Hubei, 430074, China.
Background: Red raspberry (Rubus idaeus L.) is a renowned fruit plant with significant medicinal value. Its nuclear genome and chloroplast genome (plastome) have been reported, while there is a lack of genetic information on its mitogenome.
View Article and Find Full Text PDFNat Commun
January 2025
Department of Electrical Engineering and Computer Science, Syracuse University, Syracuse, NY, USA.
In numerous applications from radio to optical frequencies including stealth and energy harvesting, there is a need to design electrically thin layers capable of perfectly absorbing electromagnetic waves over a wide bandwidth. However, a theoretical upper bound exists on the bandwidth-to-thickness ratio of metal-backed, passive, linear, and time-invariant absorbing layers. Absorbers developed to date, irrespective of their operational frequency range or material thickness, significantly underperform when compared to this upper bound, failing to exploit the full potential that passive, linear, and time-invariant systems can provide.
View Article and Find Full Text PDFProc Biol Sci
January 2025
Royal Botanic Garden Edinburgh, Edinburgh EH3 5LR, UK.
The two main extensions of rain forest in South America are the Amazon (Amazônia) and the Atlantic rain forest (Mata Atlântica), which are separated by a wide 'dry diagonal' of seasonal vegetation. We used the species-rich tree genus to test if Amazônia-Mata Atlântica dispersals have been clustered during specific time periods corresponding to past, humid climates. We performed hybrid capture DNA sequencing of 810 nuclear loci for 453 accessions representing 164 species that included 62% of Mata Atlântica species and estimated a dated phylogeny for all accessions using maximum likelihood, and a species-level tree using coalescent methods.
View Article and Find Full Text PDFJ Chromatogr A
January 2025
Dipartimento di Ingegneria Chimica Materiali Ambiente, Sapienza Università di Roma, Italy. Electronic address:
The exact moment method for the determination of the dispersion tensor in retentive porous media has been adopted to compute the dispersion coefficients, the plate height curves and the kinetic performance factors of eight different 3D printable stationary phases based on triply periodic minimal surfaces (TPMS). The two cases in which the stationary phase is impermeable (hydrodynamic dispersion) or superficially retentive have been analyzed in detail. The Carman-Kozeny relationship between permeability K, hydraulic diameter d and hydrodynamic tortuosity τ holds true for all the geometries investigated with a unique shape coefficient K.
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