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Article
The Implication of Duke Treadmill Score (DTS) on the Extent of Coronary Artery Lesions by Angiography

Authors: Tariq Mutasher Swadi --- Mazin Zamil Alshibani --- Usama Kadum Kredi
Journal: Medical Journal of Babylon مجلة بابل الطبية ISSN: 1812156X 23126760 Year: 2016 Volume: 13 Issue: 2 Pages: 405 -412
Publisher: Babylon University جامعة بابل

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Abstract

Exercise testing is used to evaluate patients with coronary artery disease. The Duke treadmill score (DTS) is a composite index for diagnostic and prognostic estimates based on results of the exercise test.A cross sectional study used to assess patients referred to The Iraqi Centre for Heart Diseases with chest pain by exercise test and coronary angiography during the period from May 2013 to April 2014. A significant coronary artery lesion: ≥50% left main stem stenosis or, ≥70% stenosis in other epicardial vessels. Significant lesion in the left main stem or three vessels defines an extensive coronary artery disease (CAD). Non extensive disease means significant lesion in one or two vessels. 80 patients included in the study (40 patients with high risk DTS, and 40 patients with non-high risk DTS). 61 patients were males (76%), 19 patients were females (24%). 38 patients of the high risk group (95%) had a significant coronary artery disease, 13 patients of them (32%) had extensive coronary artery disease. More than half of the non-high risk group (58%) had no coronary lesion, 17 patients (42%) with significant coronary disease, with one patient with extensive coronary disease (P˂0.001).The Duke treadmill test provides diagnostic and prognostic information for the evaluation of symptomatic patients for clinically suspected ischemic heart disease.


Article
Comparison of the Marginal Fitness of the Ceramic Crowns Fabricated with Different CAD/CAM Systems (An In Vitro Study)

Authors: Akram M. Abdulkareem اكرم عبد الكريم --- Adel F. Ibraheem عادل فرحان ابراهيم
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2016 Volume: 28 Issue: 4 Pages: 28-33
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: The marginal fit is the most characteristic that closely related to the longevity or success of a restoration, which is absolutely affected by the fabrication technique. The objective of present in vitro study was to evaluate the effect of four different CAD/CAM systems on the marginal fit of lithiμm disilicate all ceramic crowns.Materials and Methods: Adentoform tooth of a right mandibular first molar was prepared to receive all ceramic crown restoration with deep chamfer finishing line (1mm) and axial reduction convergence angle of 6 degree, dentoform model duplicated to have Nickel-Chromiμm master die. Thirty two stone dies produce from master die and distributed randomly in to four groups (8 dies for each group) according to the type of CAD/CAM system that used: Group A: fabricated with CERAMILL motion2 (Amann Girrbach); Group B:fabricated with CEREC in lab MCXL (Sirona);Group C: fabricated with CORiTEC 250i (imes-icore); Group D: fabricated with ZIRKONZAHN M5 (Zirkonzahn). Marginal discrepancy was measured at four points at each tooth surface. Sixteen points per tooth were measured using digital stereomicroscope at (140X) magnification.Results: ANOVA and LSD post Hoc tests were used to identify and localize the source of difference among the groups. It was found that there is a highly significant difference in the marginal gap mean values between group C and group D, and highly significant differences between group A and group D.Conclusions: From the above result we can conclude that better marginal fit values were may be exhibited by CORiTEC 250i CAD/CAM system.


Article
The Marginal Fitness of CAD/CAM All Ceramic Crowns Constructed by Two Types of Direct Digitization Techniques (An In Vitro Study)

Authors: Rana M. Khdeir رنا خضير --- Adel F. Ibraheem عادل فرحان ابراهيم
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2016 Volume: 28 Issue: 2 Pages: 30-33
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: In capturing a negative image, the digital impression secures a digital record for the purposeofdesigning and creating restorations. The introduction of scanning system presents a paradigm shift in the way of thedental impression procedure and encourages the accuracy of obtained restoration especially in the marginal areaas a result of producing accurate final impression The digital system offers many advantages over theConventional method.. The objective of this present in vitro study was to evaluate the marginal fitness of all ceramiccrowns fabricated by direct digital scanning of the prepared tooth using two types of intra-oral cameras (Bluecamcamera with strip light projection technique and Omnicam camera with video sampling technique).Materials and Methods: Sixteen sound upper first premolar teeth of comparable size were collected. Standardizedpreparation of all teeth samples were carried out to receive all ceramic crown restoration with deep chamferfinishing line (1mm), axial length (4mm) and convergence angle (6◦). The specimens divided in to two groupsaccording to the type of digital impression technique: Group A, eight prepared teeth scanned directly by Bluecamcamera; Group B, eight prepared teeth scanned directly by Omnicam camera. Then CAD/CAM all ceramic crownsconstructed for each tooth sample.Marginal discrepancy was measured at Sixteen points per tooth using digital microscope at (120X) magnification.Results: Independent sample t-test was used to identify and localize the source of difference among the groups. Itwas found that there is statistically non- significant difference in the marginal gap mean values between (group Aand group B).Conclusions: From the above result we can conclude that the two types of direct digitization techniques have thesame accuracy


Article
Computer Reverse Engineering for Reproducing Spur Gears using Digital Image Processing (DIP) Technique

Author: Mohanad Qusay Abbood
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 5 Part (A) Engineering Pages: 973-982
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Reverse Engineering (RE) is a technique that uses different approaches to obtain characteristic data of a physical object for which no drawings, documentations or computer models are available. This paper presents an experimental approach of reverse engineering for reconstructing the spur gears. 3D CAD model is made using digital image processing (DIP). Gears have been scanned using a single digital camera. The digitized data of spur gears was collected and processed using MATLAB package with Digital image processing (DIP) technique. It is worth mentioning that the accuracy of the modeling process of given piece depends on the number of points that are captured on the work piece surface. This proposed method is the best tool used in reverse engineering because it is faster and more accurate than the method used the coordinate measurement machines (CMMs). To confirm the effectiveness of the proposed method a comparison is madeusing image processing between the first data of spur gears and the data from the manufactured gears. The obtained results indicated that the proposed digital image processing system is an accurate and reliable reverse engineering for reproducing Spur gears using inexpensive equipment.


Article
The Effect of Ceramic Thickness and Number of Firings on the Color of Two All-Ceramic Systems Measured by Spectrophotometer

Authors: Haitham J. Al-Azzawi هيثم جاسم العزواي --- Zaid Abdul Mahdi Abdul Ameer Al Marah
Journal: Journal of baghdad college of dentistry مجلة كلية طب الاسنان بغداد ISSN: 16800087 Year: 2016 Volume: 28 Issue: 2 Pages: 7-13
Publisher: Baghdad University جامعة بغداد

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Abstract

Background: This in vitro study was carried out to evaluate the effects of various veneering dentin ceramicthicknesses and repeated firings on the color of lithium disilicate glass-ceramic (IPS e.max Press) and zirconium-oxide(IPS ZirCAD) all-ceramic systems, measured by clinical spectrophotometers (Easyshade Advance 4.0) .Materials and methods: The 72specimens cube-shaped have the dimension of about 11 mm in width, 14 mm inlength, 1mm in thickness, these cores divided into 3 groups according to the type of material each group have(24)core specimens. Each group had been divided into three sub-groups (each having 8 specimens) according toveneering with dentin ceramic thicknesses: as 0.5, 1, or 2 mm (n=8). IPS e.max press and ZirCAD cores group hadbeen veneered with IPS e.max Ceram dentin ceramic shade A2 according to manufacturer’s instructions and themetal group had been veneered with IPS classic dentine ceramic with shade A2 according to manufacturer’sinstructions. Repeat firings (3, 5 and 7 times) had been applied on all the specimens. Color differences amongceramic specimens had been measured using a clinical spectrophotometer (VITA Easyshade); the color data hadbeen expressed according the Vita Classic shade guide.Results: The shade of all specimens had been compared inside the subgroups and with the main groups. Thepercentage of color agreement among the subgroups showed the color of all ceramic systems had been affectingby firing interval, the ceramic thickness and brand of ceramic. The number firings intervals applied on the all ceramicsystem has a significant effect on the final color, the increase of firing number change the color to a darker andreddish color. The 5th firing interval is the point at which the major color changes happened (darker shade), and innext interval (7th firing) less color changes happened. The thickness of veneering ceramic affected the colorsignificantly. The 0.5 mm specimens in all groups showed the highest percentage of agreement (less color changes)after firing intervals, then the 1mm came and the least percentage of agreement ( highest color changes ) was the 2mm specimens. The Brand of veneering ceramic and the type of core record a significance difference in colorchanges when exposed to firing heat.Conclusion: With limit of this study, the final color of the all ceramic system definitely affected by the number of firingcycle exposed to, and the veneering ceramic thickness have a clear effect on the final shade of the all ceramictested.


Article
A PROPOSED METHOD FOR EVALUATING THE OPTIMUM LOAD IMPEDANCE IN NEGATIVE RESISTANCE RF OSCILLATORS
طريقة مقترحة لإيجاد ممانعة الحمل المثلى في المذبذبات الراديوية ذات المقاومة السالبة

Author: Firas Mohammed Ali Al-Raie
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2016 Volume: 20 Issue: 2 Pages: 1-23
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

Negative resistance radio frequency (RF) and microwave oscillators are widely used in modern wireless communication systems. In these circuits, the active device is imposed to work in the unstable region in order to present a negative resistance at its input or output port. This paper discusses the effect of the load impedance on the large signal behavior of the oscillator circuit throughout a design process of a practical 900 MHz RF oscillator circuit. New closed-form expressions for the optimum load resistance and reactance that maximize the output power have been derived analytically in terms of the transistor Z-parameters, and a design criterion for the RF oscillator is proposed based on the evaluated optimum load impedance. It has been shown through computer simulation that the optimum load resistance and reactance for maximum output power are dependent on each other. Furthermore, it has been verified that the optimum load impedance for maximum negative resistance differs slightly from its value required for maximum output power and this deviation increases with the increase in the RF power level. The designed oscillator circuit has been implemented and tested successfully.

تستخدم المذبذبات الراديوية ذات المقاومة السالبة بشكل واسع في أنظمة الاتصالات اللاسلكية الحديثة. في هذه الدوائر يتم تشغيل العنصر الفعال (الترانزستور) في المنطقة غير المستقرة لكي يُبدي مقاومة سالبة في منفذ الدخل أو الخرج. يناقش هذا البحث تأثير ممانعة الحمل على أداء المذبذبات الراديوية في حالة الإشارات عالية السعة وذلك من خلال عملية تصميم لدائرة مذبذب عملية تعمل بالتردد 900 MHz. وقد تم اشتقاق معادلات جديدة بصيغة مغلقة لإيجاد ممانعة الحمل المثلى لدائرة المذبذب بدلالة معاملات الممانعة للترانزستور، وتم اقتراح طريقة تصميم للمذبذب الراديوي بالاعتماد على ممانعة الحمل المثلى المخمّنة.وقد لوحظ خلال عملية المحاكاة بالحاسوب بأن مقاومة الحمل المثلى ومفاعلة الحمل المثلى تعتمدان على بعضهما البعض. كما لوحظ ايضا من عملية المحاكاة بأن ممانعة الحمل المثلى اللازمة لتحقيق أقصى مقاومة سالبة تختلف قليلا عن قيمتها اللازمة لتحقيق أقصى قدرة خرج، ويزداد هذا التفاوت عند زيادة مستوى قدرة الإشارة الخارجة. وقد تم تنفيذ واختبار دائرة المذبذب المصممة بنجاح.


Article
PROJECT MANAGEMENT OF BALAD`S MAJOR SEWERAGE SYSTEM BY USING THE GOAL PROGRAMMING METHOD
ادارة مشروع مجاري بلد الكبير باستخدام أسلوب البرمجة بالأهداف

Authors: أمجد عباس عبد الرحيم البلداوي --- وقاص سعد خلف
Journal: journal of Economics And Administrative Sciences مجلة العلوم الاقتصادية والإدارية ISSN: 2227 703X / 2518 5764 Year: 2016 Volume: 22 Issue: 93 Pages: 162-194
Publisher: Baghdad University جامعة بغداد

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Abstract

The project of balad's major sewerage system is one of the biggest projects who is still in progress in salahulddin province provincial - development plan that was approved in 2013 . This project works in two parts ; the 1st is installing the sewerage networks (both of heavy sewerage & rain sewerage) and the 2nd is installing the life – off units (for heavy sewerage & rain sewerage , as well) . the directorate of salahuiddin is aiming that at end of construction it will be able to provide services for four residential quarters , one of the main challenges that project's management experience is how to achieve these projects in the determined time , added cost and technical specifications although the majority of these projects have been managed with predetermined time and financial resources limits , they still need some improved strategies and more careful calculation in their time and cost management. This project was chosen for the following reasons , The first reason is that the project is currently stopped, because of the security and financial circumstances in salahulddin province in particular .this is a great manage time and cost when the work is resumed , and the second reason is during the progress of the project, the until it was stopped, the completion percentage was behind what it was planned originally . this highlights the need to study how to avoid these delays in future using a scientific and logical method , and the third reason that the project has many variables that affect the progress, which are of great importance for scientific and mathematical methods . To achieve this purpose the project was studied using modern scientific and mathematical methods , which are the curved part method (CPM) for project's real and accelerated timing the Primavera V6 software and the AutoCAD 2015 software . the goal is to benefit from these methods and software to establish a new work schedule for the project . Due to the project's various and clashed (in sometimes) objectives that are have to be accomplished in a limited time , it is very important to be careful and accurate with making the right time . It was highly needed to use an efficient mathematical model that work with all these variables in the limited time allowed and according to their priorities . This mathematical method is called the Goal Programming for multi-objective mathematical models

يعد مشروع مجاري بلد الكبير احد اكبر المشاريع التي هي قيد الانجاز في محافظة صلاح الدين ضمن خطة تنمية الاقاليم للعام 2013 , فهو مشروع ضخم يسير باتجاهين الاول مد الشبكات و الثاني انشاء محطات الرفع وللمحورين ( الثقيل والمطري ) , والتي تسعى مديرية مجاري صلاح الدين تنفيذه لخدمة اربعة احياء في قضاء بلد . إن من أهم التحديات التي تعيق ادارة المشاريع اليوم هي التأكد من انجاز تلك المشاريع في وقتها المحدد , وكذلك الكلفة و المعاير الفنية المحدد ايضا , وعلى الرغم خضوع اغلب هذه المشاريع لقيود محددة ( محددات ) تتعلق بالوقت واخرى تتعلق بالموارد المالية المخصصة للمشروع لذا فأن موضوع الوقت والكلفة في ادارة اي مشروع يحتاج الى حسابات دقيقة لهما . وقد تم اختيار هذا المشروع للدراسة لعدة اسباب مهمة , السبب الاول : إن المشروع متوقف حاليا بسبب الظروف الامنية والمادية في صلاح الدين على وجه الخصوص , وهذا دافع كبير لدراسة كيفية التعامل مع وقت وكلفة انجازه في حال استأنف العمل به , والسبب ثانيا اثناء تنفيذ المشروع كانت هنالك انحرافات عن نسب الانجاز الفعلي , مما يدفع الى توفير دراسة وبأسلوب علمي ومنطقي لتجاوز هذه الانحرافات في المستقبل , اما السبب الثالث فهو إن المشروع يحتوي على الكثير من الانشطة مما يعطي اهمية كبيرة للأساليب العلمية والرياضية التي سوف تؤثر بشكل كبير في تنفيذ المشروع بأسلوب مدروس . لذا تمت دراسة المشروع من جديد وفقا لأساليب علمية ورياضية حديثة , اختيار اسلوب المسار الحرج (CPM) بوصفه احد اساليب الادارة العلمية للمشاريع لإيجاد وقت انجاز المشروع الطبيعي والتعجيلي , وبما ان لإدارة هذا المشروع اهداف متعددة تسعى الى تحقيقها في مدة زمنية محددة , الامر الذي يتطلب الكثير من الدقة في الوصول للقرارات المناسبة , فكان من الاجدر استخدام اسلوب رياضي كفوء لبناء نموذج رياضي متعدد الاهداف يعمل مع جمــيع هذه المتغـيرات في المدة الزمنية المحددة وبحــسب اولوياتهــا وتسمى البرمجة الهدفية ( (Goal Programming , وكذلك تم استخدام بعض البرامج الجاهزة لرسم الشبكة كبرنامج (Primavera V6 ) والبرنامج الهندسي المعروف (AUTO CAD 2015 ) , وبرنامج (Win QSB) لحل الأنموذج متعدد الاهداف , ومحاولة الافادة من مميزات هذه البرامج في جدولة المشروع .

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