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Article
Performance Analysis of Routing Protocols in Manets

Author: Ahmed M. Jasim
Journal: DIYALA JOURNAL OF ENGINEERING SCIENCES مجلة ديالى للعلوم الهندسية ISSN: 19998716/26166909 Year: 2018 Volume: 11 Issue: 1 Pages: 64-69
Publisher: Diyala University جامعة ديالى

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Abstract

Mobile ad hoc networks (MANETs) are characterized by the absence of centralized management and the lack of any infrastructures. The frequent topology changes and variable propagation conditions make a routing is the most important issue, therefore, it becomes necessary for nodes within the networks to use appropriate routing algorithms. In this paper, we evaluate the performance of AODV, DSR, OLSR and GRP routing protocols using OPNET modeler 14.5 simulation software. In the simulated mobile ad hoc network, we made all nodes receiving FTP traffic from a FTP server as common source. we increased the possibility of multi-hop routes between nodes with each other or from the server to the nodes by placing them randomly in the network. Our simulations have suggested many of the scenarios to all selected protocols in the identical environmental conditions so as to evaluate their performance with respect to routing overhead, throughput, end-to-end delay and routing load.

Keywords

MANET --- OLSR --- AODV --- DSR --- GRP.


Article
Preparation and Characterization of novel 3-(4-chloro phenyl)-1- nitro phenyl-5-(substituted phenyl)-formazans
تحضير مشتقات جديدة ٣- (٤- كلورو فنيل) -١- نايترو فنيل -٥- ( فنيل معوض بموقع بارا) فورمازاين وتشخيصها

Author: Ahmed M. Jasim أحمد مجيد جاسم
Journal: Journal of Basrah Researches (Sciences) مجلة ابحاث البصرة ( العلميات) ISSN: 18172695 Year: 2011 Volume: 37 Issue: 5A Pages: 90-98
Publisher: Basrah University جامعة البصرة

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Abstract

In the present research, a series of 3-(4-chloro phenyl)-1- nitro phenyl-5-(substituted phenyl)-formazans (5a-d) were synthesized by the condensation of schiff base(3)and diazonium salt of various substituted aromatic amines (4a-d). The Schiff base (3) was itself synthesized by the condensation of 4-nitro aniline(1) with 4-chloro benzaldehyde(2). All the reaction were routinely monitored and purity was determind on thin layer chromatography using coated aluminum plates and spots were visualized by exposing the dry plates in iodine vapours. The structures of the compounds have been confirmed by elemental analysis, Mass spectroscopy , 1H NMR, U.V, IR spectral data and melting points.

في هذا البحث حضرت سلسلة من مشتقات جديدة لمركب ٣- (٤- كلورو فنيل) -١- نايترو فنيل -٥- ( فنيل معوض بموقع بارا) فورمازاين بوساطة تكاثف قاعدة شف(مركب وسطي) N -(٤- كلورو بنزليدين)- ٤- نايتروانليين مع ملح الدايازونيوم لامينات اورماتية معوضة بمجاميع مختلفة بالموقع بارا,وقاعدة شف حضرت من تكاثف بارا نايتروانلين مع بارا كلورو بنزالديهايد .تمت متابعة التفاعلات باستخدام تقنية كروموتوغرفيا الطبقة الرقيقة وشخصت المركبات المحضرة بوساطة اطياف الرنين النووي المغناطيسي للبرتون ,الاشعة تحت الحمراء ,الاطياف المرئية وفوق البنفسجية ,طيف الكتلة وقيست درجات الانصهار لجميع المركبات المحضرة.

Keywords


Article
Evaluation the Quality Three Different Obturation Technique Using Multi-Slice Computed Tomography: An In-Vitro Study

Authors: Huda A. Abduallah --- Ahmed M. Jasim --- Omar B. Taha Ahmed M. Jasim
Journal: Tikrit Journal for Dental Sciences مجلة تكريت لعلوم طب الاسنان ISSN: 20731213 Year: 2014 Volume: 3 Issue: 1 Pages: 9-16
Publisher: Tikrit University جامعة تكريت

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Abstract

After endodontic space has been completely cleaned, shaped and disinfected, a three-dimensional obturation of this space will be the ultimate objective of endodontic therapy. With a durable three dimensional obturation any communication with the periodontium will be eliminated and prevented. The aim of this study was to use multi-slice CT scanning to determine: (i) number of voids (ii) diameter or length of voids and (iii) presence of voids at material/tissue interfaces in root canals obturated with: (a) E & Q Master (b) Lateral Condensation, and (c) Soft Core system. Thirty freshly extracted human mandibular premolar teeth were used in this study. After preparation of the root canals, the teeth were divided into three groups with 10 teeth in each groups. G1 obturated with E&Q master, G2 obturated with Lateral Condensation, and G3 was obturated with Soft Core. GuttaFlow was used as sealer for all groups. After obturation all the specimen were analyzed with multi-slice CT, the data obtained was statistically analyzed using ANOVA test followed by Duncan's multiple range test ,a value of p< 0.05 was considered statistically significant.Voids are observed in all groups, Neither technique was free of voids or perfectly smooth. Overall, the canals that obturated with E&Q master showed the lowest number of voids (3.0), whereas those obturated with lateral condensation showed the highest number (3.9) and the differences was statistically significant. The canals that obturated with Soft core showed the highest mean of voids diameter ( 0.77 mm) , whereas those obturated with E&Q master and lateral condensation had the lowest mean (0.62 mm and 0.61 mm) respectively, and the differences were statistically significant. The percentage of outer voids was higher for all techniques than the inner voids. The presence of inner voids was the highest in canals that obturated with soft core system (9.230%). Conclusion: E&Q master of obturation show the lowest number of voids. Obturation with Soft core show the highest mean of voids diameter. In all obturation techniques, the outer voids was higher than inner voids.

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