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The studies presented in this paper are part of the problematic that aims the simulation and characterization of an anechoic chamber. A new approach based on the Finite Integral Method (FIT) was presented and evaluated for modeling a full anechoic chamber for antenna near/far-field measurement. The probe as well as the Antenna Under Test (AUT) are replaced by their Huygens sources calculated separately. This new technique has allowed us to gain in terms of computing resources and also to reduce the simulation time, compared to other solutions. The convergence and the stability of the proposed method are guaranteed by an autoregressive filter and an adaptive mesh. The results obtained show that the maximum error as well as the depolarization of the wave in the Quiet Zone (QZ) of the chamber are of the order of 1 dB. The calculation time is 15 h, which represents a gain of 90%.

International audience; Objective: As well known, using a single body worn sensor exposimeter introduces systematic errors on the measurement of the incident free space electric field strength. This is because the body creates around it high, intermediate and low level field zones, which depend on the direction of arrival of the incident field. The goal of this work is to propose an efficient method for the reduction of these errors. Methods: After classifying the perturbations induced by the body on the measured electric and magnetic fields thanks to realistic numerical simulations, we then propose a two-sensor setup in conjunction with simple semi-empirical correction formulas, in order to compensate these perturbations. Results: At 942 MHz, when the two sensors are placed in any opposite sides of the body at chest height, the worst case, maximum and average errors respectively decrease to 12% and 3% compared to 83% and 22% for measurement techniques using a single sensor, or 32% and 11% when using the average value of the measurements. Conclusion: The error related to the measurement in the presence of the body was significantly reduced by the proposed method making use of two opposite sensors, E-field and H-field at the chest. Significance: The conformity of exposure to EMF in terms of reference values according to the ICNIRP is given in the abscence of the human body. The interest of this work lies in the reduction of the errors made when measuring the field in the presence of the body.

In order to maintain the training quality and ensure efficient learning, the introduction of a scalable and well-adapted evaluation system is essential. An adequate evaluation system will positively involve students in the evaluation of their own learning, as well as providing teachers with indicators on the student's strengths, the specific encountered difficulties and the false or misunderstood studied parts. In this context, we present, in this article, a novel intelligent evaluation methodology based on fuzzy logic and knowledge based expert systems. The principle of this methodology is to reify abstract concepts of a human expertise in a numerical inference engine applied to evaluation. It reproduces, therefore, the cognitive mechanisms of evaluation experts. An im-plementation example is presented to compare this method with the classical one and draw conclusions about its efficiency. Furthermore, thanks to its flexibility, different kinds of extensions are possible by updating the basic rules and adjusting to possible new architectures and new types of evaluation.

The correct evaluation of human exposure to electromagnetic fields is necessary in daily life because of the increase in RF devices and their proximity to the user. This assessment can be performed by using a personal dosimeter which measures the level of the electromagnetic field with the presence of the human body. The aim of this work is to present a correction law to reduce the measurements errors of a RF dosimeter due to the presence of the human body. To evaluate the performance of this law we used two errors: the Body Reflection Errors and Body Shadowing Errors. Two approaches combining electric and magnetic fields are studied in near and far field situations. Simulation results show that the application of the proposed correction law, which uses two diametrically opposite measuring point around the body, significantly reduces measurement error. Assessing the human exposure in near and far fields situations reassures users and especially the workers they are in an environment that respect the laws and standards of exposure to electromagnetic waves.

In this paper, we present some interactive simulations developed mainly for educational purposes in physics, mathematics, and engineering. A new horizon of understanding some concepts via interactive animations has opened a new research dimension in the learning theory. In this work, our interest is focused on the design of interactive and didactic simulations for teaching and learning differential equations. The code is written in ActionScript/Flash to enjoy all the benefits of this technology in the multimedia field, Internet and mobile phones (smartphones and tablets). This powerful tool stimulates students' interest to understand/learn abstract mathematical concepts in physics. These simulations provide additional insight for concepts that need a lot of resources and time. These simulations are applied in e-learning environments and engineering education.

In sciences education, experimental methods are crucial for a better understanding of basic physical phenomena. Moreover, practical sessions and experimental methods give students an opportunity to develop their perceptions and to increase their interest in a given topic. In the electronic educational curriculum, one of the keys for a successful achievement of educational goals is the good comprehension and perception of electromagnetic fields and wave propagation phenomena especially in the high frequency domain. In this scope and taking advantages of the progress of a new stage of distance learning known as mobile learning (or m-learning), we present in this paper some interactive applications mainly developed for educational purposes in electronics and electromagnetics studies. In these mobile simulations, the students will be able to visualize the abstract and "invisible" physical phenomena and thus strengthen the profound understanding of the subject topic. Moreover, these kinds of apps are available for all the mobile devises using the Android operating system (Smartphones, Tablets, PDAs and Notebooks).

We present in this paper the calibration of a correction law to overcome the electric field (e-field) measurement errors due to the presence of the dosimeter in the vicinity of the human body. The Correction law proposes to use only two measuring points close to the body. These measurements are made at regularly goshawks separate points of the body, either in the chest, abdomen or waist. The goal is to propose a useful distributed worn-body dosimeter who can apply a correction law to these separate values compared to the maximum value known beforehand. This correction law is currently derived to simulation for GSM, DCS and UMTS downlink Bands and shortly performed by measurements. Assessing the real EMF exposure value in real-time is the key question for sanitary authorities as well as for industry (Manufacturer and Operator).

International audience; The probe correction technique applied to reactive near-field characterization is based on a deconvolution process. However, the classical deconvolution based on an inverse Fourier transform has a restrictive limitation. It is based on the use of noiseless measurement data. Consequently, measurement noise makes the result obtained by the classical deconvolution based technique inefficient and requires an extremely low noise measurement facility. In this paper, a method to improve the probe correction stability when using corrupted measurement data is presented. The proposed constrained least squares filtering algorithm (CLSF) uses an inverse filtering approach that takes into account the statistical characteristics of the measurement noise. Computations data with electromagnetic software of two different structures validate this method and illustrate its reliability.