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Most of the real world problems involving decisions are part of a complex environment, where multiple objectives and points of view have to be taken into account and the diversity of value systems are present. This observation motivated our study, which focuses on the development and/or validation of mathematical models and computer tools for complex-problems evaluation via expert knowledge. As an example of a complex situation, the evaluation of catch-up sessions is treated. Usually, in a catch-up evaluation the final score is either the average or the maximum value and the choice is in most cases unjustified. Thus, the evaluation of the objectives achievement could only be in turn deficient. Using our new intelligent evaluation system based on Knowledge Based Expert Systems (KBES) and fuzzy logic lead us to discover new models for evaluating such complex problems. The principle of this system is to reproduce the cognitive mechanisms of an expert in evaluation.

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.

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.

Mobile Ad hoc Network consists of some nodes that are stand randomly in operational environment. Because nodes are without any predefined infrastructure and mobility then there are susceptible to intrusions and attacks. Securing is an important field in this type of network. Intrusion Detection Systems (IDSs) may act as defensive mechanisms, since they monitor network activities in order to detect malicious actions performed by intruders, and then initiate the appropriate countermeasures. IDS for MANETs have attracted much attention recently and thus, there are many publications that propose new IDS solutions or improvements to the existing. In this paper, we propose a new IDS architecture for MANETs, this architecture is a combination model hierarchical based on clusters and cooperation model based on a multi-agent system (SMA). In this paper, we are used AUML language to describe the operation of different agents of our architecture.

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).

In this work, we present a new technique based on the deconvolution method for the probe correction for antenna near field measurements. In fact, because of the response of the probe to other components of the field radiated by the Antenna Under Test (AUT), to the influence of the geometric parameters of this one and to the problems related to the measuring surface. An unwanted error appear between the voltage recovered by the probe from AUT and the real field radiated by this one, and a step of post-processing is therefore necessary to correct this one. A probes based on an Open Ended Rectangular WaveGuide (OERWG) and the half-wave dipole are used in this study to validate this approach. Thus, the spatial response of the probe is calculated and validated by tests in front of real antennas. The results obtained show that the calculated reference field and the reconstructed one are confused for the three antennas under test.

The personal radiofrequency dosimeters are increasingly used for the workers exposure estimation to the electromagnetic radiations in terms of reference level of the fields. The presence of the human body at the vicinity of dosimeter compromising its measurement accuracy. In this paper, the study of interaction between personal radiofrequency dosimeter and human body is presented. Firstly, we treat the error introduced by the presence of the body and an approach to reducing this impact by adding elements in the dosimeter structure. Indeed, by introducing a metal ground plane and optimizing the height of antenna-ground plane, we can estimate at 10% close the level of incidental field, that is to say a considerable reduction impact of the body on the dosimeter. We also study the stability of the intrinsic characteristics of dosimeter (isotropy and front to back ratio). Different simulations were performed in the GSM 900 band with the finite integration technique. In the context of the design of worn-body radiofrequency dosimeter it's very useful to master these interaction results.

The probe is one of the major components building an indoor system for antenna near field measurement. In this paper, we present a geometric characterization of the Open Ended Rectangular waveguide and the pyramidal horn probes, used to measure the tangential component of the electric field. The results obtained show that the field and the voltage are proportional to the dimensions of the probes. They increase with the parameter h and they pass through a maximum for the parameters Psi and Pci.

Mobile Ad Hoc Networks (MANETs) are susceptible to a variety of attacks that threaten their operation and the provided services. Intrusion Detection Systems (IDSs) may act as defensive mechanisms, since they monitor network activities in order to detect malicious actions performed by intruders, and then initiate the appropriate countermeasures. IDS for MANETs have attracted much attention recently and thus, there are many publications that propose new IDS solutions or improvements to the existing. In this paper, we study the different existing IDS architectures for MANETs. We briefly present for each architecture, after an analysis, the strengths and weaknesses, the methods/techniques that have been proposed to improve the performances and the provided security services. Then, we propose a new IDS architecture for MANETs, this architecture is a combination model hierarchical based on clusters and cooperation model based on a multi-agent system (SMA). In this architecture, agents use a knowledge related to a global security ontology, it can be used to infer new detection rules.

Mobile Ad Hoc Networks (MANETs) are susceptible to a variety of attacks that threaten their operation and the provided services. Intrusion Detection Systems (IDSs) may act as defensive mechanisms, since they monitor network activities in order to detect malicious actions performed by intruders, and then initiate the appropriate countermeasures. IDS for MANETs have attracted much attention recently and thus, there are many publications that propose new IDS solutions or improvements to the existing. In this paper, we study the different architectures existing the IDS for MANETs. We briefly present for each architecture, after an analysis, the strengths and weaknesses, the methods/techniques that have been proposed to improve the performances and the provided security services. Then, we propose a new IDS architecture for MANET, this architecture is a combination of model hierarchical based on clusters and cooperation model based on a multi-agent system (SMA). In this architecture, agents use a knowledge base related to a global security ontology, it can be used to infer new detection rules.

With the flourish of online education and distance learning, it's become very important to make the evaluation in e-learning scientifically and objectively. This paper presents an intelligent fuzzy evaluation system based on our innovative evaluation method where management rules made by the experts are used to help, optimize and decide. On this basis, we develop an evaluation method and algorithm based on the fuzzy logic concepts and new information technologies. Thus, intelligent applications are possible if one wish to automate the management and decision while making an alarm system based on relevant indicators. Finally, we come up with an “expert system” that can provide some solutions to the problems of measurement theory. In addition, we present a concrete example to compare this method with the traditional one then draw conclusions on the effectiveness of this method.

Mobile Ad Hoc Networks (MANETs) are susceptible to a variety of attacks that threaten their operation and the provided services. Intrusion Detection Systems (IDSs) may act as defensive mechanisms, since they monitor network activities in order to detect malicious actions performed by intruders, and then initiate the appropriate countermeasures. IDS for MANETs have attracted much attention recently and thus, there are many publications that propose new IDS solutions or improvements to the existing. In this paper, we study the different existing IDS architectures for MANETs. We briefly present for each architecture, after an analysis, the strengths and weaknesses, the methods/techniques that have been proposed to improve the performances and the provided security services. Then, we propose a new IDS architecture for MANETs, this architecture is a combination model hierarchical based on clusters and cooperation model based on a multi-agent system (SMA). In this architecture, agents use a knowledge related to a global security ontology, it can be used to infer new detection rules.

MANETs are a collection of mobile nodes that dynamically form a temporary network and are capable of communicating with each other without the use of a network infrastructure or any centralized administration. Due to the flexibility provided by their dynamic infrastructure MANETs are vulnerable to many types of security attacks. Furthermore, many conventional security solutions have been developed. However, these proposals suffer from the problems of tests and evaluations. Among these solutions the intrusion detection systems (IDS). To improve the quality of protection of MANETs provided by intrusion detection systems (IDS), we provide assessment of detection and test procedures more effective. In this paper, we make a thorough analysis of existing attacks. For this we propose a new system to classify attacks based on attributes that appear to be the best classification criteria to generate test-cases. We also apply the classification tree method (CTM) to select test-cases to attack. Finally, we use the CTE (Classification Tree Editor) tool to generate and select test-cases.

In this work we present a virtual laboratory for studying the wave propagation proprieties. This virtual lab is used to study the propagation of electromagnetic waves in most environments, in readable and progressive manner. It allows students to apply many equations views in the course. The software uses the finite-difference time-domain (FDTD) that has been successfully applied in many engineering fields. In addition, an easy-to-use MATLAB GUI handles all the parameters of the FDTD simulation and computes theoretical values of characteristics parameters of the wave propagation in different mediums. The software allows understanding the phenomena of electromagnetic wave propagation step by step; starting with the case of one dimension to three dimensions, and finally, it allows approaching particular cases like the metamaterials and plasma. Java programming language is used for programming numerical calculations, creating visualization suitable for simulations and offers the possibility to run simulation remotely.

The aim of the work presented here is to develop an accurate and cheap electromagnetic simulation software that provides a virtual laboratory for studying the wave propagation proprieties. The numerical method used is the finite-difference time-domain (FDTD) that has been successfully applied in many engineering fields. In addition, an easy-to-use MATLAB GUI handles all the parameters of the FDTD simulation and computes theoretical values of characteristics parameters of the wave propagation in different mediums. The software allows understanding the phenomena of electromagnetic wave propagation in a progressive manner starting with the case of one dimension to three dimensions, and finally it allows approaching particular cases like the metamaterials.

In this paper, we present an interactive simulation of a Metal-Oxide-Semiconductor structure, based on a qualitative approach. The code is written in ActionScript / Flash to enjoy all the benefits of this technology in the multimedia field. In addition, our simulation combines theoretical and practical concepts on the same graphical interface: it shows the impact of physical and electrical parameters on the behavior of a MOS structure or a transistor TMOS. Moreover, it provides the physical reasons of the parameters influence that can serve to evaluate the relevance of approximations commonly used. This simulation is applied in engineering education.