1,240 research outputs found
Production of Hard Grade Bitumen for Using in High Modulus Asphalt Concrete
قد تتعرض الخرسانة الاسفلتية الاعتيادية لعدة اضرار مثل شقوق الكلل والتخدد وتتفاقم درجة هذه الاضرار مع الظروف المناخية القاسية والحمل المروري المتكرر. يمكن اعتبار الخلطة الاسفلتية العالية المرونة المصممة وفقا للطريقة الفرنسية (EME)) أحد الحلول المهمة للحد من هذه الاضرار. ان انتاج هذا النوع من الخليط يتطلب اسفلت (كمادة رابطة) عالي الصلابة. البحث الحالي يتضمن طريقة جديدة لأنتاج الاسفلت بتدرج اختراق نوع hard)) ليلائم متطلبات الاسفلت العالي الصلابة المستخدم لأنتاج الخلطة الاسفلتية العالية المرونة المصممة وفقا للطريقة الفرنسية. العمل المختبري يتضمن خلط البوليمر ومصلبه مع الاسفلت الاعتيادي لأنتاج الاسفلت الجديد العالي الصلابة. نظرا لأن شقوق الكلل هي أكثر المخاوف المتعلقة بالأسفلت (كمادة رابطة) العالي الصلابة والخلطة الاسفلتية العالية المرونة، لذلك تمت إضافة حبيبات المطاط الى الاسفلت المنتج العالي الصلابة لتحسين أداء التبليط في مقاومة شقوق الكلل. تم اجراء اختباري مطياف الاشعة تحت الحمراء ومسح المجهر الالكتروني للأسفلت الاعتيادي وللأسفلت العالي الصلابة. كانت القيمة المثلى المختارة للمضافات لانتاج الاسفلت العالي الصلابة المستخدم في الخلطة الاسفلتية العالية المرونة هي 4% و0.4% من وزن الاسفلت للنوفولاك والهكسامين على التوالي، بينما نسبة حبيبات المطاط لتحسين المرونة هي 0.5%. أظهرت نتائج الاختبارات المجهرية والاشعة تحت الحمراء للاسفلت المنتج حدوث تداخلا ميكانيكيا بين الاسفلت والمضافات أدى الى تحسن كبير في الخواص الميكانيكة للاسفلت المنتج. الاسفلت المنتج قد حقق متطلبات الاسفلت العالي الصلابة وبالتالي يمكن استخدامه في انتاج الخلطة الاسفلتية العالية المرونة المصممة وفق الطريقة الفرنسية.The conventional Hot Mix Asphalt (HMA) may suffer from several distress such as fatigue cracks and rutting. These distresses increase with severe climate conditions and reputation of traffic load. The High Modulus Asphalt Concrete (HMAC) designed according to the French method (EME) can be considered as one of the important solutions for these distresses. The production of HMAC requires hard grade bitumen. The current research involved a novel way to produce hard grade bitumen (asphalt binder) to be consonant with the requirements of hard grade bitumen used for a HMAC. The experimental work involved mixing polymer and cross-linking agent with conventional bitumen to get the new bitumen. Since the most concern with hard grade bitumen and HMAC is the fatigue cracks, Crumb Rubber (CR) was added to the obtained bitumen to improve the fatigue performance of the pavement. Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electronic Microscope (SEM) tests were carried out on the conventional and hard grade bitumen. The optimal value of additives was selected to meet the requirement of hard grade bitumen was 4% Novolac from weight of bitumen and 10 % of Hexamine from weight of Novolac (i.e. 0.4% of weight of bitumen), while the selected CR ratio to improve flexibility was 0.5% from weight of bitumen. FTIR and SEM test results showed that a mechanical interaction was occurring between the bitumen and the additives leads to greatly improve the mechanical properties of resulting bitumen. The obtained bitumen is satisfied to required standards and can be used for HMAC according to French method
Development a Teaching Methods using a Cloud Computing Technology in Iraqi Schools
الوضع الحالي للتعليم في معظمه الكترونياً. العوامل مثل الخوادم، ومساحة التخزين، والبرمجيات هي أكثر وضوحا من أي وقت مضى. الحوسبة السحابية هي الحوسبة المستندة الى الإنترنت والتي تسمح للمستخدمين بتبادل الموارد والبرامج والمعلومات. في سياق العراق، لم تترجم زيادة الإنفاق على التعليم إلى تحسين بيئات التعلم. هذا العمل يهدف إلى زيادة كفاءة التعليم في العراق من خلال استعراض الخصائص المرتبطة مع مزودي الحوسبة السحابية مثل مايكروسوفت وجوجل وأمازون لزيادة الفائدة للطلبة والمدرسين والعاملين في قطاع التربية. وهذا العمل أيضاً هو محاولة لتحديد الاساليب التي تقدم الخدمات والأدوات الغنية وبأسعار معقولة من خلال بناء نموذج مناسب للحوسبة السحابية للمدارس العراقية. يتكون هذا النموذج العملي من ثلاثة أجزاء رئيسية: التهيئة، التنفيذ والمراقبة، والتقييم والمراجعة. هذا النموذج يجمع بين الحوسبة العامة والخاصة لتقديم خدمات متعددة ويُمكن الطلبة والجهات المستفيدة من الوصول الى المعلومات خارج المدارس. المشاكل المرتبطة بأمن وخصوصية البيانات منخفضة جدا وتحت السيطرة في هذا النموذج، كون البيانات محمية وراء الجدران النارية مع الاحتفاظ بالوصول عن بعد الى الخدمات العامة، قابلية التوسع، التكاليف المنخفضة، الكفاءة، خيارات التوصيل والتشغيل. هذه الدراسة أيضا تقلل من التحديات الداخلية والخارجية التي يواجهها تنفيذ هذا النموذج من خلال استمرار التقييم والمراجعةThe current state of education is mostly electronic. Factors such as servers, storage space, and software are more prominent than ever before. Cloud Computing is defined as an Internet-based computing space that allows its users to share resources, software and information. In the context of Iraq, increased educational spending has not translated into improved learning environments. This work intends to increase the efficiency of education in Iraq through reviewing the characteristics associated with cloud computing providers, such as Microsoft, Google and Amazon, in the context of enhancing the advantages to students, teachers, and other stakeholders. The work will also try to determine approaches that offered rich and affordable services and tools through posing a suitable Cloud Computing Model for Iraqi Schools (CCIS). This particular model is made up of three major parts; preparation, implementation and monitoring, and evaluating and reviewing. The CCIS model combines public and private clouds in the provision of multiple services to the students and enables the formation of links outside of schools. Problems associated with security and data privacy are quite low and under control in this model, as they are defended beyond firewalls alongside remote services, scalability, low costs, efficiency, and functional plug and play options. This study will also decrease the challenges faced by the model internally and externally via constant appraisals and review
Use of Infrared Light to Improve Breast Sonographic images
It is well known that sonography is not the first choice in detecting early breast tumors. Improving the resolution of breast sonographic image is the goal of many workers to make sonography a first choice examination as it is safe and easy procedure as well as cost effective. In this study, infrared light exposure of breast prior to ultrasound examination was implemented to see its effect on resolution of sonographic image. Results showed that significant improvement was obtained in 60% of cases
Speed and Current Limiting Control Strategies for BLDC Motor Drive System: A Comparative Study
As a result of increasing the use of the brushless direct current (BLDC) motor in many life applications instead of the traditional motors, it is important to list and specify the more for its controlling methods. This paper presents a number of speed and current controlling methods as hysteresis band, variable dc-link bus voltage and pulse width modulation (PWM) controlling methods. These controlling methods have proportional integral derivative (PID) gains which are optimized by using particle swarm optimization (PSO) algorithm. By using fast Fourier transform (FFT) analysis to study the controller behavior from frequency analysis of the output signals and compute total harmonic distortion (THD), it can specify the more useful controlling method. The framework is modeled and fabricated by using Matlab/Simulink
Numerical Solutions of Two-Dimensional Vorticity Transport Equation Using Crank-Nicolson Method
يهتم هذا البحث بالحلول العددية لمعادلة نقل الحركة الدوارنية (VTE) ثنائية الابعاد مع شروط ديرشلت الحدودية المتجانسة . وبالتحديد، نشتق معادلة الفروقات المنتهية ((Crank-Nicolson لهذه المسألة. بالإضافة إلى ذلك، نناقش اتساق واستقرار الطريقة. علاوة على ذلك، يتم التطرق الى تجربة عددية لدراسة تقارب طريقة (Crank-Nicolson) ولتصور الرسوم البيانية المتقطعة لكلا من دوال الحركة الدورانية والتدفق. تظهر النتيجة النظرية أن الطريقة المقترحة متسقة، في حين أن النتائج العددية تظهر أن الحلول مستقرة عند خطوات مساحة صغيرة وفي أي مستويات زمنية.This paper is concerned with the numerical solutions of the vorticity transport equation (VTE) in two-dimensional space with homogenous Dirichlet boundary conditions. Namely, for this problem, the Crank-Nicolson finite difference equation is derived. In addition, the consistency and stability of the Crank-Nicolson method are studied. Moreover, a numerical experiment is considered to study the convergence of the Crank-Nicolson scheme and to visualize the discrete graphs for the vorticity and stream functions. The analytical result shows that the proposed scheme is consistent, whereas the numerical results show that the solutions are stable with small space-steps and at any time levels
Mathematical modeling for cryptography using Jafari transformation method
Data protection is representing a huge trade in the modern era; the vast communication development gave this field increased attention from all sorts of parties (friends and foes); integral transforms have played a decent role in many methods that are proposed to be used in the cryptography field.
In this work, the Jafari integral transform has been used as a part of a symmetric key system, by implementing a practical example in encryption and decryption; Jafari integral transform has proven its capability to be invested in cryptography and in the data security field in general
Optimization of delamination resistance of vacuum infused glass laminate aluminum reinforced epoxy (GLARE) using various surface preparation techniques
GLARE (glass-reinforced fibre–metal laminate ) is aluminum based material of fiber metal laminate (henceforth FML) that is often fabricated by expensive autoclave procedure. In this study, the process of Injected Molding or (also known as VARTM was employed as a cost-effective alternative to produce GLARE. Several aluminum surface preparation procedures are applied to improve the interlaminar shear strength. A T3 temper 2024 aluminum alloy with 1*1 plain fabricated glass fabrics were used to make GLARE composites. GLARE consists of two aluminum sheet as external layer and glass fabric as internal layers. Four sets of aluminum sheets were prepared, one unanodized and three other anodized. Three different anodizing procedures (constant voltage mode, increasing voltage mode and decreasing voltage mode) have been adopted in this research. Two types of curing treatments were applied on VARTM fabricated specimens. According to ASTM D1876 T-peel test standard, the sets of prepared specimens have been tested to examine the adhesive bonding strength and fracture toughness of mode-I. The obtained results which include force-displacement curves, peak loads and fracture toughness were showed that a significant improvement for anodized specimens with all voltage modes. The first curing treatment offered better results than second curing treatment. The best improvement was obtained from anodized specimen with decreasing voltage mode cured by the first treatment which reaches to six times the results obtained from unanodized specimen. The delamination behavior for this specimen was verified numerically
Phytochemical Characterization using GC-MS Analysis of Methanolic Extract of Moringa oleifera ( Family Moringaceae) Plant Cultivated in Iraq
Objective: The aim of the present study was to characterize the Moringa oleifera plant cultivated in Iraq for the presence of biologically active phyto-chemicals using methanolic extracts of the plant (leaves and seeds) . This study was determined by using Gas Chromatography –Mass spectrometry, while the mass spectra of the compounds found in the extract was matched with the National Institute of Standards and Technology (NIST) library. Methods: In the present investigation, methanolic extracts of Moringa oleifera were screened for the presence of steroids, alkaloids, tannins, flavonoids, terpenoids, anthraquinoin and cardiac glycosides by standard qualitative test procedures and further this study was extended by analyzing the potent bioactive compounds in the methanolic extract of plant using GC-MS analysis. Results: reveal the presence of different compounds (about 100 compound) in the Moringa plant extract among them alkaloids, terpenoids steroids, saturated and unsaturated fatty acid, aromatic and aliphatic hydrocarbon, polyphenolic compounds . GC-MS was done using the database of National Institute of standard and Technology (NIST). Conclusion: Results confirmed the presence of therapeutically potent compounds in the Moringa extract predominantly steroids, flavonoids and terpenoids. Keywords: Moringa oleifera, biologically active, Phytochemicals, GC-MS analysis
ASSESSMENT OF VITAMIN D THERAPY EFFECT ON INFLAMMATORY MARKERS IN PEDIATRIC PATIENTS WITH TYPE I DIABETIC
Objective: The objective of this study is to estimate the effect of Vitamin D3 supplementation on endogenous Vitamin D3 level and inflammatory biomarkers in newly diagnosed pediatric patients.Methods: The patients were given oral Vitamin D3, and they divided into three groups: The first group (25 healthy pediatrics), the second group (25 newly diagnosed pediatric patients) treated with daily insulin regimen only, and the third group (25 newly diagnosed pediatric patients) treated with Vitamin D3 (2000 IU/day) with daily insulin regimen; all patients were treated for 90 days; and blood samples were taken at baseline and after 45 days and 90 days of starting Vitamin D3 to assess its potential effect on the levels of Vitamin D, serum calcium, serum alkaline phosphatase levels, and other inflammatory markers.Results: The results of the current study showed that serum IL-1β significantly declined in patients receiving Vitamin D3, while serum Vitamin D3, serum calcium, and interleukins-4 were significantly increased in patients receiving Vitamin D3.Conclusion: Vitamin D3 in a daily dose of 2000 IU/day for 90 days results in favorable immune response and increase of serum Vitamin D3 for pediatric new diagnosed Type 1 diabetes mellitus patients
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