A Novel FDTD Algorithm for Analyzing Microwave Filters with Imperfectly Conductors

In this paper, we propose a new FDTD algorithm to design microwave filters with imperfectly conductors. For this purpose, we have developed a mesh function to describe the thin film material. Then, we have applied our algorithm for the analysis of a microwave resonator performance. The effects of finite conductivity and thin film thickness have also been investigated. Computed results are in good agreement with simulated data using CST electromagnetic tool

Design of Multiband-Filters for Mobile Radio Applications

In this paper, a new multi-standard filter with four resonance frequencies is proposed for radio-mobile including GSM/4G LTE, WLAN and 5 G applications. The design and synthesis is resolved using a new formulation of the FDTD method. The metal finite conductivity and thickness are rigorously taken into account. The FDTD computed results are in good agreement with simulated data obtained with CST electromagnetic tool

An Enhanced FDTD Algorithm for Multilayer Waveguides and Filters

In this paper, a new formulation of the finite difference time domain technique was applied for efficient hybrid-mode analysis of inhomogeneous planar waveguides and filters. An enhanced analytical formula for the cut-off frequency was also proposed for a three-layer waveguide while the shielding effect was investigated on band-pass filter performance. The computed S-parameters are in good agreement with simulated ones obtained with the CST electromagnetic tool

Using a participatory qualitative risk assessment to estimate the risk of introduction and spread of transboundary animal diseases in scarce‐data environments

International audienceThis article presents a participative and iterative qualitative risk assessment framework that can be used to evaluate the spatial variation of the risk of infectious animal disease introduction and spread on a national scale. The framework was developed through regional training action workshops and field activities. The active involvement of national animal health services enabled the identification, collection and hierarchization of risk factors. Quantitative data were collected in the field, and expert knowledge was integrated to adjust the available data at regional level. Experts categorized and combined the risk factors into ordinal levels of risk per epidemiological unit to ease implementation of risk-based surveillance in the field. The framework was used to perform a qualitative assessment of the risk of introduction and spread of foot-and-mouth disease (FMD) in Tunisia as part of a series of workshops held between 2015 and 2018. The experts in attendance combined risk factors such as epidemiological status, transboundary movements, proximity to the borders and accessibility to assess the risk of FMD outbreaks in Tunisia. Out of the 2,075 Tunisian imadas, 23 were at a very high risk of FMD introduction, mainly at the borders; and 59 were at a very high risk of FMD spread. To validate the model, the results were compared to the FMD outbreaks notified by Tunisia during the 2014 FMD epizootic. Using a spatial Poisson model, a significant alignment between the very high and high-risk categories of spread and the occurrence of FMD outbreaks was shown. The relative risk of FMD occurrence was thus 3.2 higher for imadas in the very high and high spread risk categories than for imadas in the low and negligible spread risk categories. Our results show that the qualitative risk assessment framework can be a useful decision support tool for risk-based disease surveillance and control, in particular in scarce-data environments