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Article
Influence different audio codecs on the performance of VOIP traffic over integrating WLAN and WAN networks

Author: Ali M. Alsahlany1 Ali M. Alsahlany1
Journal: Journal Of Ma'aen مجلة مَعِين ISSN: 26165708 Year: 2017 Issue: 7 Pages: 3-16
Publisher: University of Alkafeel جامعة الكفيل


Article
Human pulp response after direct pulp capping with an adhesive system

Author: Ali M. Abdul Kareem
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2006 Volume: 18 Issue: 1 Pages: 25-29
Publisher: Baghdad University جامعة بغداد

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Abstract

ABSTRACT
Background: The adhesive systems are experimentally used in direct pulp capping procedure. The aim of this study was to evaluate the histological responses of pulp tissues after direct pulp capping with an adhesive agent.
Materials and Methods: The pulps of twenty human teeth scheduled for extraction were mechanically exposed and capped with an adhesive system and calcium hydroxide cement for 60 days. The teeth were extracted and prepared for examination under light microscope for inflammatory responses and dentin bridge formation.
Results: The slides showed that there were variable responses which ranged from moderate to severe and progressive extension of tissue necrosis with time for teeth capped with the adhesive system. After the application of calcium hydroxide paste, only mild tissue response was elected with complete hard tissue bridging.
Conclusion: Based on the experimental conditions, the application of the adhesive system in direct contact with mechanically exposed pulp cannot lead to acceptable repair of dentin-pulp complex.
Keywords: Adhesive, pulp capping, calcium hydroxide, pulp response. (J Bagh Coll Dentistry 2006; 18(1) 25-29)

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Article
The relation between overbite and facial, maxillary and mandibular dimensions

Author: Ali M. Al-Attar
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2011 Volume: 23 Issue: 2 Pages: 105-109
Publisher: Baghdad University جامعة بغداد

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Abstract

ABSTRACT
Background: Overbite value is important in treatment of various malocclusions; the aim of this study was to
investigate the relation between the overbite and facial, maxillary and mandibular dimensions.
Materials and methods: The sample of this study included 80 pre-treatment digital true lateral cephalometric
radiographs of Iraqi subjects aged 18-25 years, collected from the files of the subjects attending the Orthodontic
Department in the College of Dentistry, University of Baghdad. The 80 radiographs were divided into four groups (20
radiographs each) according to overbite value. Three angular, fifteen linear measurements and two ratios were
used.
Results: There were significant differences in most vertical linear measurements, while no significant differences in
horizontal linear measurements between over bite groups also there were strong negative correlation between over
bite and SN-MP, PP-MP, gonial angles.
Conclusions: There were significant correlation between over bite and facial, maxillary and mandibular dimensions.
Patients in open bite group showed longer lower facial height, maxillary and mandibular alveolar and basal heights,
symphyseal height and tendency toward backward rotation of the mandible than other overbite groups patients.
Key words: Overbite, facial dimensions. (J Bagh Coll Dentistry 2011;23(105-109).

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Article
Evaluation of interfacial bond strength of repaired composite resins

Author: Ali M. Abdul Kareem
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2006 Volume: 18 Issue: 2 Pages: 32-34
Publisher: Baghdad University جامعة بغداد

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Abstract

ABSTRACT
Background: Repair of composite restorationsis a choice if absence of caries is guaranteed. The purpose of this study was to evaluate the interfacial shear bond strength of the immediately repaired composite specimens.
Materials and methods: Sixty specimens from 2 types of composite were made in a special mold and polymerized with light. Three methods of surface treatment of the initial layer were done prior to the application of the repair layer including the use of matrix strip or not and abrasion. The specimens were subjected to shear force from the testing machine and mean for each group was calculated.
Results: The non–air inhibited specimens showed the highest values of shear bond strength (mean =13.1 Mpa) which was significantly different from the bur abraded specimens (p<0.05), but insignificant from the air inhibited specimens (p>0.05) for both types of composite.
Conclusion: The absence of air inhibited layer by using matrix strip increase the interfacial bond strength of the immediately repaired composite with inferior interfacial bonding for the bur abrasion method.
Keywords: Composite, bond strength, repair. (J Bagh Coll Dentistry 2006; 18(2) 32-34)

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Article
Counter Mode Development For Block Cipher Operations

Author: Ali M. Sagheer
Journal: AL-Rafidain Journal of Computer Sciences and Mathematics مجلة الرافدين لعلوم الحاسوب والرياضيات ISSN: 18154816 Year: 2009 Volume: 6 Issue: 1 Pages: 133-144
Publisher: Mosul University جامعة الموصل

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Abstract

الملخص
هناك نوعان أساسيان من الخوارزميات المتماثلة: التشفيرالكتلي والتشفير الانسيابي. يعمل التشفيرالكتلي على نص واضح و نص مشفر طوله 64 لبنة (64-bits) ومن الممكن أطول. يعمل التشفيرالانسيابي على نص واضح و نص مشفر طوله لبنة واحدة أَو بايت (وأحياناً كلمة طولها 32 لبنة) في كل مرة. التشفيرالكتلي يشفر كل كتلة من النص الواضح بنفس المفتاح لينتج كل كتلة من النص المشفر ، بينما التشفيرالانسيابي يشفر كل لبنة او بايت من النص الواضح بمفتاح مختلف لينتج كل لبنة او بايت من النص المشفر.
في هذه البحث نقدم ثلاث تطويرات من نمط العداد لطريقة تشفير(DES). مزجت هذه التطورات بين فوائد نمط العداد مع الأنماط الأخرى. هذا يعطي أمنية جيدة لتحقق الغرض العام للارسال الكتلي التوجهَ، الوصول عشوائي، إلارسال الانسيابي التوجهَ على القناة المشوشة.

ABSTRACT
There are two basic types of symmetric algorithms: block ciphers and stream ciphers. Block ciphers operate on blocks of plaintext and ciphertext—usually of 64 bits but sometimes longer. Stream ciphers operate on streams of plaintext and ciphertext one bit or byte (sometimes even one 32-bit word) at a time. With a block cipher, the same plaintext block will always encrypt to the same ciphertext block, using the same key. With a stream cipher, the same plaintext bit or byte will encrypt to a different bit or byte every time it is encrypted.
In this paper we introduce three developments of Counter Mode of Operation of Block cipher. These developments merge between advantages of Counter Mode with other Modes. This gives a good secure Modes for General purpose block-oriented transmission Authentication, Random access, Stream-oriented transmission over noisy channel.

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Article
Retrospective Assessment of the Success Rate of Single-Visit Root Canal Treatment: A Clinical and Radiographical Analysis

Author: Ali M. Rashid
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2008 Volume: 8 Issue: 1 Pages: 104-109
Publisher: Mosul University جامعة الموصل

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Abstract

Aim: The purpose of this study was to determine retrospectively, clinically and radiographically the suc-cess rate of single–visit root canal treatment and determine the possible factors that could affected there prognosis.Materials and Methods: nine–hundred and sixty–five single–visi1 cases, of which 322 present for re–examination appointment ranging from 6 months to 5 years from the day of treatment were considered. Clinical and radiographical data were used to form overall impression of the outcomes for each case at the time of re–examination. Available demographics and treatment information of these 322 cases were compiled for comparison. The number of treatment visits was not determined by a pre-treatment diagnosis or a re–assessment of the pulp status upon entry in to the tooth; therefore both vital and necrotic cases, as well as those with and without periradicular pathosis, Were included. Statistical analysis was carried out using Chi–square test and considered variations in failure rates based on gender, tooth type, position and arch. A t–test was used to evaluate data on age. Results: The overall success rate was 92.8%. No statistically significan1 differences were seen based on gender and arches. The data show almost younger ages more candidate for failure rate than older age group. Statistically, anterior teeth were more successful than posterior teeth. Conclusion: The success rate of single–visit root canal therapy was engorgement for this approach .Both gender and arches were not affecting the treatment outcome in this study, where as the treatment for older age and anterior teeth more successful than younger and posterior teeth respectively.


Article
Design & Implementation of Fractional - N Frequency Synthesizer

Author: Ali M. N. Hassan
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2006 Volume: 12 Issue: 2 Pages: 415-427
Publisher: Baghdad University جامعة بغداد

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Abstract

This research involves design & implementation of fractional – N frequency synthesizer with the following specifications: Frequency range (2350– 2750) MHz, Step size (1 kHz), Switching time 8.9 µs, & phase noise @10 kHz = -115dBc & spurious -69 dBc The third order Fractional –N technique was chosen to satisfy the design requirements. In this system the Σ∆modulator placed on digital phase-locked loop to control the fractional value of the frequency division ratio thereby eliminating spurious and allowing good phase noise performance. The development in I.C. technology provides the simplicity in the design of fractional –N frequency synthesizer because it implements the phase frequency detector(PFD) , prescalar, Σ∆modulator & reference divider in single chip. Therefore our system consists of a single chip contains (low phase noise PFD, charge pump, prescalar, Σ∆modulator & reference divider), voltage controlled oscillator , loop filter & reference oscillator. The application of this synthesizer in frequency hopping systems, wireless transceivers ,GSM & radar because it has high switching speed ,low phase noise & low spurious level.

يصف هذا البحث تصميم وبناء مركب ترددات من نوع (Fractional - N) وبالمواصفات التالية : مدى الترددات الخارجة (2350-2750) ميكا هرتز، واقل سعة قفزة 1كيلو هرتز ،زمن تحويل 8.9مايكرو ثانية ومستوى ضوضاء طوري - 115. ديسبيل عند 10000 هرتز من التردد الخارج.ومستوى الطفيليات - 69 ديسبيل.ان تقنية الجيل الثالث (Fractional - N) تم اختيارها لتحقيق متطلبات التصميم. في هذه المنظومة , مرحلة تضمين من نوع (Σ∆) تم وضعها في دائرة إقفال الطور الرقمية للسيطرة على على القيم الكسرية لمقسم التردد.وبهذا تم ابعاد الترددات الطفيلية وتحسين ضوضاء الطور. التطور الحاصل في الدوائر المتكاملة جهز البساطة في تصميم مركب الترددات من نوع (Fractional - N) وذلك لأنه دمج كاشف التردد والطور ,ومقسم التردد الثنائي , ومقسم التردد ومرحلة تضمين من نوع (Σ∆) في شريحة رقيقة واحدة. لذلك منظومتنا تتكون من شريحة تحتوي على كل من )كاشف ترددات وطور ذو ضوضاء طوري قليل،مضخة شحنة دقيقة،مقسم ترددات مبرمج ، ومقسم تردد ثنائي(p/( p+1)) مبرمج ومرحلة تضمين من نوع (Σ∆)) مرشح ترددات واطئة ،مذبذب ترددات ذو سيطرة جهدية، ومذبذب مرجعي. هذه الشرحة الرقيقة التي تحتوي كل من كاشف ترددات وطور مقسم ترددات مبرمج ومقسم تردد ثنائي .التطبيقات لهذا المركب في منظومات القفز بالتردد , و الرادار, و المرسلات والمستلمات اللاسلكية،GSM وذلك لأنها تمتلك خاصية ضوضاء طوري قليل وسرعة تحويل عالية ومستوى طفيليات اقل.


Article
Motivations of Code-Switching in the Classrooms of the Department of English

Author: . Ali M. Jukil
Journal: Alustath الاستاذ ISSN: 0552265X 25189263 Year: 2012 Issue: 200 Pages: 522-535
Publisher: Baghdad University جامعة بغداد

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Abstract

Code-switching is a term which is widely used by sociolinguists. The phenomenon of code-switching occurs in a bilingual community. So, code-switching is observed in the Department of English and it is performed between the native language of the students (Kurdish) and a foreign language (English) that students are going to gain competence in. The objective of the study is to find out how code-switching can be used as a teaching device in learning a foreign language. This study is divided into five sections. The first is a brief introduction about the term and the phenomenon. The second section is devoted to the language situation in the Department of English. The third one deals with the motivations of code-switching and the fourth section offers the concluding remarks while the fifth one is about the pedagogical implications.

ان مصطلح مزج اللغتين واحد من الظواهر اللغوية تستعمل بشكل منتشر من قبل المهتمين بدراسة المجتمع اللغوي وكيفية استعمالها من قبل اللذين يتكلمون لغتين، لغة الام ولغة ثانية. وان هدف هذا البحث هو ايجاد وتحديد الدوافع بهذه الظاهرة اللغوية وكيفية استعمالها من قبل طلاب ومحاضري قسم اللغة الانكليزية وايضا تحديد كيفية استعمال هذه الظاهرة كأداة تعليمي لتدريس اللغة الانكليزية. يقع هذا البحث من خمس مباحث خصصت مبحث الأول لمقدمة قصيرة حول التعريف و نوعية الظاهرة. والمبحث الثانى هو حول الوضع اللغوي في القسم و يتناول المبحث الثالث الى واقع التي تؤدي بالطلاب و المحاضرين لاستعمال هذه الظاهرة اللغوية. وتستعرض المبحث الرابع النتائج التي توصلت اليها هذه الدراسة، و الطرق التدريسية لكيفية استعمال هذه الظاهرة في تعليم اللغة الانكليزية بحثت في المبحث الخامس، و في النهاية استعرضت قائمة بالمصادر.

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Article
CONSERVATIVE MANAGMENT OF CLUBFOOT (PONSETI METHOD )

Author: Ali M.AL-Shidededi
Journal: KUFA MEDICAL JOURNAL مجلة الكوفة الطبية ISSN: 1993517X Year: 2008 Volume: 11 Issue: 2 Pages: 156-162
Publisher: University of Kufa جامعة الكوفة

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Abstract

Objective of the study The aim of the study is to practice Ponseti method on certain number of clubfoot babies below one years of age and to see if those babies can be managed excellently by this method without the need for extensive corrective surgery.(1-6) .

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Article
Partially Purification and Biological Properties of Shigella dysenteriae Type 1 Shiga Toxin

Author: Ali M. Al-Muhana
Journal: KUFA MEDICAL JOURNAL مجلة الكوفة الطبية ISSN: 1993517X Year: 2008 Volume: 11 Issue: 1 Pages: 121-131
Publisher: University of Kufa جامعة الكوفة

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Abstract

A toxin from Shigella dysenteriae type 1 (strain BB46) was partially purified. The steps used to purified the toxin included intermittent sonic oscillation of bacterial grown in modified synicase broth, ammonium sulphate precipitation, and chromatography on diethylaminoethyl sephadex and carboxymethyl sephadex. The partial purified preparation had a specific activity of 41.8×105 CD50/mg protein in Vero cells. The clinicopathological effects of intravenous administered partially purified toxin in rabbits and intraperitonial injection in mice were studied. The LD50 values were 0.2 and 40 µg/kg body weight in rabbits and mice, respectively. The clinical feature included diarrhea in some animals and a progressive flaccid paralysis, usually culminating in death. The histopathology of rabbits was characterized by edema and hemorrhage in the spinal cord and edema in the brain.

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