Publications Scientifiques
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Item Students misconceptions about light in Algeria(2009) Blizak, Meriem Djanette; Chafiqi, Fouad; Kendil, DjamelPhysics education research has shown that students have difficulties in learning essential optics concepts. Therefore, in this present work we deal with student’s conceptions in geometrical optics field. Our objective is to show the Algerian students misconceptions. We proposed to 246 students in first year university (aged 18–21) a closed questionnaire where most of its questions were already used by other researchers. The misunderstandings identified were compared with those in literature. The results show that our students have the same misconceptions, related to the propagation of the light, the vision, the refraction and the reflexion, as the students in other countries (Andersson, Çiğdem ŞAHİN, Galili, Goldberg, Viennot,…). We investigate new students “misconception” concerning the propagation of the light in the vacuumItem Formalisation de la logique de description ALC dans l'assistant de preuve Coq(2009) Chaabani, Mohamed; Mezghiche, Mohamed; Strecker, MartinLe langage d’ontologie Web (Web Ontology Language OWL) est un langage utilis ́e pour le web s ́emantique. OWL est bas ́e sur les logiques de description (LD), une famille de lan- gages adapt ́es pour la repr ́esentation et le raisonnement sur des connaissances d’un domaine d’application d’une fa ̧con structur ́ee et formelle. Le web s ́emantique est actuellement l’un des champs d’application des m ́ethodes formelles, dont l’objectif est d’assurer leur fiabilit ́e. Un point essentiel de l’application de ces m ́ethodes formelles est la preuve de va- lidit ́e des raisonnements dans des LDs, comme celle de la terminaison, l’ad ́equation (soundness) et la compl ́etude d’un raisonneur. Dans ce papier, on pr ́esente une sp ́ecification formelle de la syntaxe et de la s ́emantique de ALC, qui est consid ́er ́ee comme un repr ́esentant typique d’une large gamme de LDs. On prouve pour cette logique les pro- pri ́et ́es d’ad ́equation, de compl ́etude et de terminaison dans l’assistant de preuve Coq.Item Speed-up of high accuracy analog test stimulus optimization(1999) Khouas, Abdelhakim; Derieux, AnneAnalog integrated circuit testing and diagnosis is a very challenging problem. The inaccuracy of measurements, the infinite domain of possible values and the parameter deviations are among the major difficulties. During the process of optimizing production tests, Monte Carlo simulation is often needed due to parameter variations, but because of its...Item Methodology for Fast and Accurate Analog Production Test(1999) Khouas, Abdelhakim; Derieux, AnneThis paper describes a new technique to reduce the number of simulations required during analog fault simulation. The method takes into account process parameter variations and aims to reduce the number of the computational expensive Monte Carlo simulations often required during analog fault simulation. In section I a review of the state of the art.Item Speed-up of High Accurate Analog Test Stimulus(1999) Khouas, Abdelhakim; Derieux, AnneAnalog integrated circuit testing and diagnosis is a very challenging problem. The inaccuracy of measurements, the innite domain of possible values and the parameter deviations are among the major diOEculties. During the process of optimizing production tests, Monte Carlo simulation is often needed due to parameter variations, but because of its expensive computational cost, it becomes the bottleneck of such a process. This paper describes a new technique to reduce the number of simulations required during analog fault simulation. This leads to the optimization of production tests subjected to parameter variations. In section I a review of the state of the art is presented, section II introduces the algorithm and describes the methodology of our approach. The results on CMOS 2-stage opamp and conclusions are given in sections III and IVItem Analog Fault Detection based on Statistical Analysis(Hal, 2000) Khouas, Abdelhakim; Derieux, AnneIn analog circuits, process variations result in physical parameter variations. Simulated values must then be considered with there tolerance intervals. Consequently, contrarily to digital circuits where the outputs are either '0' or '1' such that we can decide without ambiguity whether a fault is detectable or not, for analog circuits the fault detectability is a vague problem as the fault can either be completely detectable, partially detectable or completely undetectable which makes it very diOEcult to take a decision. In order to solve this decision problem, we have introduced the probability to detect fault (PDF) function which allows to formalize the problem of analog fault detection under parameter variationsItem Optimized Statistical Analog Fault Simulation(2001) Khouas, Abdelhakim; Dessouky, Mohamed; Derieux, AnneA new statistical method for analog fault simulation is presented. The method takes into account process parameter variations and aims to reduce the number of the computational expensive Monte Carlo simulations often required during analog fault simulation. The technique is illustrated by means of a fifth-order low-pass switched-capacitor filterItem The Effect of CO Reducing Atmosphere on the Structural and Optical properties of SnO2: F films Deposited on a Si( N+)/Si(P) solar cell(2006) Zair Tala-Ighil, Razika; Boumaour, Messaoud; Maallemi, Abderrezak; Melhani, kheira; Iratni, A.Item Characterization of Thin Layer SnO 2 /Glass by Neutrons Reflectometry(Scientific.net, 2009) Khelladi, Mohamed Fadel; Izerrouken, M.; Kermadi, Salim; Tala-Ighil, RazikaThe thermal annealing behavior of the SnO2 thin films elaborated by sol-gel method has been studied by the neutrons reflectivity technique. From the fit of the experimental data using Parratt32 software program developed at HMI, Berlin, scattering length density, thickness and roughness are extracted. The obtained results show that the film thickness increases with the increasing annealing temperature, and the roughness is higher at 500 °C. Whereas, approximately, the same scattering length density is obtained after each annealing temperatureItem Contact Resistance Determination For Multi-crystalline Silicon Solar Cells By Using Transmission Line Method (TLM)(2008) Tala-Ighil, Razika; Sali, S.; Oussalah, Slimane; Boumaour, Messaoudhe main objective in solar cells realization consists in increasing their performances. The mechanisms of this increase obey specific phenomena of physics. There is necessarily a contact resistance value behind each value of conversion efficiency. The question is how to quantify the contact resistance and what is its behaviour with different temperature profiles and consequently with the conversion efficiency. This work responds to all of these questions. We have taken square multicrystalline silicon wafers of 10 cm sides. These wafers have followed the traditional process steps i.e.: chemistry, diffusion, silicon nitride PECVD deposition and metallization of the front grid with TLM (Transmission Line Method) mask. The TLM measures are obtained using a test bench which includes a four-point prober and an analyzer. The contact resistance is deduced by the plot of the resistance versus the TLM line distance. It represents the R(D2), R(D3), R(D23), R(D4) and R(D34) where D2, D3, D23, D4 and D34 are the TLM distances. The TLM resistance is the half of the intersection of the slope R(D) with the y-axis. A profile of the evolution of the contact resistance versus the screen printing temperature annealing from 650°C to 800°C for the multi-crystalline silicon solar cells has been obtained.