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The measurement of glycemia is impacted by several constraints; those constraints have to be identified and quantified when designing an electromagnetic noninvasive sensor. The second phase concerns the level of the influence of these constraints. In this work, we investigated the impact of vein radius located in the forearm on a resonant microwave sensor to measure glycemia. We performed a numerical simulation using COMSOL Multiphysics of a proposed tissue model that was in contact with a microwave resonator. Some other factors affect the measurement, such as temperature, perfusion, sensor positioning and motion, tissue heterogeneity, and other biological activity. The sensor must be robust to the above-mentioned constraints. Because vein size changes from one person to another, the dielectric properties seen by the sensor will be different. This has been demonstrated by the change created in the resonance frequency of the simulated sensor for different vein sizes. The second constraint that was assessed is the dosimetry. The specific absorption rate (SAR) of any electromagnetic device should be evaluated and compared with SAR limits in the safety standards to ensure the safety of the user. Simulation results are in good agreement with SAR limits in the safety standards.

The Fe60(CoO)40 nanostructured alloys have been prepared from pure iron and cobalt oxide powders by mechanical alloying technique within a high energy planetary ball-mill. Morphology, microstructural and magnetic properties of this powder were investigated by a Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and Vibrating sample magnetometer (VSM). The effect of time of milling on magnetic behaviour of Fe(CoO) nanostructured composite has been investigated. Apparition of new phase polycrystalline sample having a size in the range of 12 and 26 nm, it is confirmed by X-ray diffraction testing. The enhanced magnetic properties and structural behaviour of the nanoparticle are due by the diminution of size of crystallite. After 40 hours of milling, the appearance of spinel structure of CoFe2O4. The reduction in particle size leads to a significant increase in magnetic hardening, the coercive field at room temperature increases from 6 Oe to 208 Oe

In this work, we carried out the study of electrical characteristics with two-dimensional numerical analysis by using the Aided Design (TCAD Silvaco) software for CdS/CuInGaSe2 (CIGS) thin solar cells. Their structure is composed of a thin CIGS solar cell in the configuration: ZnO(200 nm)/CdS(50 nm)/CIGS (350 nm)/Mo. Then ZnO is used for conductive oxide contacted transparent front of the cell. For rear contact, the molybdenum (Mo) is used. The layer of the CdS window and the shape of the CIGS absorber is the n-p semiconductor heterojunction. The performance of the cell was evaluated by applying the defects created in the grain joints of polycrystalline CdS and CIGS material and CIGS/CdS interface in the model, and the physical parameters used in the TCAD simulations have been calibrated to reproduce experimental data. The J–V characteristics are simulated under AM1.5 illumination conditions. The conversion efficiency (η) 20.10% has been reached, and the other characteristic parameters have been simulated: the open-circuit voltage (Voc) is 0.68 V, the circuit-current density (Jsc) is equal to 36.91 mA/cm2, and the form factor (FF) is 0.80. The simulation results showed that the molar fraction x of the CIGS layer has an optimal value around 0.31 corresponding to a gap energy of 1.16 eV, this result is in very good agreement with that found experimentally.

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In this paper, a comparative study between two open ended coaxial sensors with and without cavity is presented. Those sensors are used for materials characterization (composite, dielectric, liquid) and surface defects detection. First Galerkin’s method in the Fourier transform domain is applied to the determination of the resonant frequencies of an open-ended coaxial sensor. The obtained results are used for the realization of two open ended coaxial sensors with and without cavity. The defects detection testbed includes a network analyzer, two open ended coaxial sensors and two aluminum plates with defects of various depths. The proposed method is based on the reflected electromagnetic waves from defected surface, wish are captured by a coaxial sensor. The behavior of the sensor is then studied through reflection coefficient measurements for each kind of defect. A comparative study between the realized sensors is also carried out.

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