Abdelaziz Amroune , Mokhtar Diaf

كلية الرياضيات والاعلام الآلي-جامعة محمد بوضياف - المسيلة · الجزائر

In this dissertation, we have presented some basic notions about fuzzy sets and rings. Also, we gave an overview of fuzzy subrings and their properties. Then, we studied the fuzzy ideals associated with a fuzzy subring. We, ended this work with a general conclusion.

رابح لصفر, طالم علي, طيفور ابراهيم

كلية العلوم الاقتصادية، التجارية وعلوم التسيير-جامعة ابن خلدون – تيارت · الجزائر

عبد المجيد قدي, وسيلة طالب

كلية العلوم الاقتصدية وعلوم التسيير‎-جامعة سعد دحلب - البليدة-جامعة سعد دحلب - البليدة · الجزائر

سمير سرور, مازن حداد, محمد صالح تيسير المثقال

كلية الطب البشري-جامعة دمشق · سوريا

أحلام أحمد الهنا, ميرزا علاف

كلية طب الأسنان-جامعة دمشق · سوريا

Boubaker Ben Hauoa, Soumaia Abbas

كلية الرياضيات وعلوم المادة-جامعة قاصدى مرباح ورقلة · الجزائر

Abstract:In this work, undoped tin dioxide (SnO2) and fluorine doped tin dioxide (SnO2: F) films were elaborated with spray ultrasonic technique. SnCl2 and NH4F were used as sources of SnO2 and fluorine doping respectively. The films were deposited on 480°C heated glass. Effects of fluorine doping and films thickness on the optical, structural and opto-electrical properties of undoped and fluorine doped SnO2: F (FTO) thin films were investigated. X-ray diffraction (XRD) patterns showed that both SnO2 and SnO2: F films were polycrystalline with tetragonal rutile structure. The preferential orientation for SnO2 was along (211) plane whereas SnO2: F preferential orientations were along (200) planes. The calculated crystallite sizes were in the average 11.57–28.16 nm. Optical transmittance spectra of the films showed high transparency of about 73-87% in visible region. The optical gap, for SnO2 and SnO2: F films, was found to be in the range 3.62-3.93 eV. Plasma frequencies of the films were found to be in the range 1.317×1015-1.395×1015 Hz leading to estimated optical carrier concentration in the range of 1.575×1021-1.767×1021cm-3.The electrical study reveals that the films have n-type electrical conductivity and depend upon fluorine concentration. The electrical carrier concentration was found to be in the range 2.04×1019–0.04×1019 cm-3 which was lower than the optically estimated one. Calculated figure of merit for FTO thin films revealed maximum value about 13.0410-3 (-1) at =700 nm at fluorine concentration 6 wt. % for 440 nm thickness. FTIR spectra confirmed the formation of SnO2, after fluorine doping a new vibration mode of Sn-F was appeared around 710 cm-1. Contact angle on the FTO films surfaces was measured which was in the range of 66-109°. CA measured values reveals that the films surfaces have hydrophobicity properties. The elaborated FTO thin films are promising to be used as window layer in solar cells and as self cleaning materials.

Kamel Benachenhou

جامعة سعد دحلب البليدة · الجزائر

Le but de ce travail de thèse est l'analyse de l'étage d'acquisition réalisée au niveau d'un récepteur GNSS regroupe tous les systèmes satellitaires existants et ceux en phase de développement, de ce fait les récepteurs hybrides GPS/Glileo de viennent un domaine de recherche prometteur.l'acquisition décide la présence ou l'absence d'un signal GNSS en comparant une cellule sous test avec un seuil fixe préétabli, fournissant ainsi une estimation du délai du code et le Doppler associé, cependant dans les situations de signaux faibles ou fortement bruités, la performance d'acquisition des s'affaiblit en produisant un nombre important de fausses alarmes. Notre travail s'articule autour de deux axes. En premier lieu, nous proposons une nouvelle structure pour l'acquisition des signaux GPS/Galileo en introduisant un détecteur CA-CFAR à la sortie de l’étage d'acquisition du canal pilote ou de données. Dans ce contexte, les formulations mathématiques proposées des probabilités de détection et de fausses alarmes ont été validées par simulations Monte-Carlo. Pour améliorer la performance et tirer profit de l'existence des deux canaux nous avons fusionné les deux canaux dotés de détecteurs CFAR par les règles AND et OR. Dans la deuxième partie, la structure de l'acquisition adaptative proposée a été implémentée sur carte FPGA.

AbdulAziz Al Majed, هشام محمد

كلية هندسة البترول وعلوم الأرض-جامعة الملك فهد للبترول والمعادن · السعودية

Recent advances in technology have led to the development of streamline simulation techniques aimed at the estimation of the best injection profile to acquire excellent efficiency improvement in the water flooding process. The present study evaluates three recent automated optimization methodologies on the responses of increasing efficiency of enhanced oil recovery using water flooding. The programming procedures for the three presented methods are highlighted. Two artificial models and two real models are simulated to find out the advantages and disadvantages of each optimization process. In addition, helpful software was utilized that was developed at KFUPM-RI and capable of dealing with streamline simulation output and generating efficiency plots. The results obtained from this study highlighted the differences in the presented methods of productivity arising and water flooding efficiency. Furthermore, it was noticed that Huthali method had the greatest influence in increasing flooding efficiency performance. However, less oil amount is produced compared to the other two methods for the same time scale.

أمال الزاير , سومية بوقسيمة , شهرزاد برابح

كلية الآداب واللغات والعلوم الاجتماعية-جامعة عين تموشنت - بلحاج شعيب · الجزائر

ريحاب شعبان, عبد الحكيم بو غرارة, فايزة بوبكر

كلية العلوم الإنسانية والاجتماعية-جامعة الدكتور يحيى فارس بالمدية · الجزائر