32 research outputs found
Enhanced Design of Narrowband Filters Based on The Extraordinary Transmission Through Single Fishnet Structures
A systematic method for the efficient design of narrowband filters founded on the extraordinary transmission via single fishnet structures (SFSs) is presented in this paper. Essentially, due to its strong resonant behavior, this phenomenon is proven suitable for the implementation of high-Q devices. The new design formulas are derived through the combination of full-wave numerical simulations and curve fitting algorithms. Also, adequate mathematical criteria are defined for the evaluation of the filters\u27 linear performance, indicating that the transmitted electromagnetic waves remain practically undistorted in the frequency band of interest. Then, by exploiting the previously developed relations, proper correction factors are introduced in the existing SFS equivalent circuit expressions, which hardly increase the overall computational complexity. This quantitative modification leads to an enhanced characterization of SFSs, as key components for diverse applications. Finally, several limitations as well as possible ways of extending the featured algorithm to more complicated structures and higher frequency bands are briefly discussed
Improved Finite-Difference Time-Domain Algorithm Based on Error Control for Lossy Materials
Abstract-This paper discusses the development of a reducederror finite-difference time-domain algorithm, capable of handling conducting media in an efficient manner. Founded on a spatially extended stencil, the proposed scheme introduces a novel design procedure, whose basic idea is to enforce conditions of the continuous space to the discrete level. In this way, we derive reliable space-time models for 2-D Maxwell's equations, minimizing the inherent phase and amplitude deviations. A high degree of adaptivity is also accomplished, as the spectral reliability range can be adjusted according to problem-dependent needs. Consequently, an upgraded discretization strategy is provided, which exhibits the same computational complexity with the conventional scheme. Index Terms-Finite-difference time-domain (FDTD) methods, high-order schemes, lossy media, optimized algorithms
Modern EMC analysis I: time-domain computational schemes
The objective of this two-volume book is the systematic and comprehensive description of the most competitive time-domain computational methods for the efficient modeling and accurate solution of contemporary real-world EMC problems. Intended to be self-contained, it performs a detailed presentation of all well-known algorithms, elucidating on their merits or weaknesses, and accompanies the theoretical content with a variety of applications. Outlining the present volume, the analysis covers the theory of the finite-difference time-domain, the transmission-line matrix/modeling, and the finite
Modern EMC analysis techniques II: models and applications
The objective of this two-volume book is the systematic and comprehensive description of the most competitive time-domain computational methods for the efficient modeling and accurate solution of modern real-world EMC problems. Intended to be self-contained, it performs a detailed presentation of all well-known algorithms, elucidating on their merits or weaknesses, and accompanies the theoretical content with a variety of applications. Outlining the present volume, numerical investigations delve into printed circuit boards, monolithic microwave integrated circuits, radio frequency microelectr
Rigorous ADIâFDTD analysis of leftâhanded metamaterials in optimallyâdesigned EMC applications
Anthelmintics residues in raw milk. Assessing intake by a children population
Anthelmintics, such as benzimidazoles and probenzimidazoles, are veterinary drugs used against
endoparasites in food producing animals. A number of these drugs are considered responsible for
embryotoxicity and teratogenicity. The residue levels of Albendazole, Febantel, Fenbendazole,
Mebendazole and some of their metabolites (Albendazole sulphoxide, Albendazole sulphone, Fenbendazole
sulfone) were assessed in 123 (42 goat, 69 sheep, 12 bovine) raw milk samples collected
from all farms throughout Southern Greece. Sample analysis was performed by HPLC with Diode
Array Detector. A high percentage (27.6%) of the samples examined was found to be positive for the
investigated compounds. In 14 samples (11.4%), the residuesâ concentration exceeded the established
Maximum Residue Limits.
Estimated Daily Intakes were calculated for a population of 723 children aged 10-12 years. Data
on milk consumption were obtained by personal interview through a 7-day food frequency questionnaire.
The maximum Estimated Daily Intakes for the anthelmintic residues, concerning raw milk, did
not exceed the current Acceptable Daily Intake
Combined FVTD/PSTD Schemes with Enhanced Spectral Accuracy for the Design of Large-Scale EMC Applications
A generalized conformal time-domain method with adjustable spectral accuracy is introduced in this paper for the consistent analysis of large-scale electromagnetic compatibility problems. The novel 3-D hybrid schemes blend a stencil-optimized finite-volume time-domain and a multimodal Fourier-Chebyshev pseudo-spectral time-domain algorithm that split the overall space into smaller and flexible areas. A key asset is that both techniques are updated independently and interconnected by robust boundary conditions. Also, combining a family of spatial derivative approximators with controllable precision in general curvilinear coordinates, the proposed method launches a conformal field flux formulation to derive electromagnetic quantities in regions with fine details. For advanced grid reliability at dissimilar media interfaces, dispersion-reduced adaptive operators, which assign the proper weights to each spatial increment, are developed. So, the resulting discretization yields highly rigorous and computationally affordable simulations, devoid of lattice errors. Numerical results, addressing detailed comparisons of various realistic applications with reference or measurement data verify our methodology and reveal its significant applicability