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تطوير ادوات جديدة في نظام مودل Developing New Tools in Moodle System

المستخلص: E - learning is the use of IT in learning and teaching. This usage improved the quality of learning and teaching through facilitating access to resources and remote collaboration among teachers and students. E - Learning makes it easier to create and distribute learning materials, independently of geographical or time limits. It allows students to exchange information and participation in activities.There are many systems (software) development for management of E - learning (LMS). These systems provide tools for simulation the traditional learning, development and support the electronic learning.LMS provides many tools to create, manage the examination, evaluate the grades and spread question types.The general aim of this thesis is to develop the LMS that has been increasingly used having widespread in E - Learning in many countries. This system is "Moodle" which designed to supporting electronic learning.Moodle system is not satisfying conditions of the traditional exam copybook that is used in examination committees in Iraqi universities in terms of security and accuracy."Single view" report in Moodle system allows the teacher to edit grades of "Quiz" activities.Moodle system not provided question type in which the answering method is done through selecting word from a given text; this idea is a suggested product for the development of Moodle website in 2014 and doesn't have solution yet.In this thesis, we proposed three main proposals : 1. Development of Moodle system to use it in the examinations in Iraqi Universities through designing and implementation of new module named "Teacher view" to provide "The Electronic Exam Copybook" which simulated the traditional exam copybook that is used in the examination committees in these universities for assessment of student's answers. It also presents documentation of detailed information about student's attempt on examination and calculates the student's grades. This "Electronic Exam Copybook" satisfies all conditions of the traditional exam copybook in terms of security and accuracy. Also, the proposed module provides students' results in English and Arabic languages and manual of this module.2. Overcome of the weakness in "Single view" report in Moodle system.3. Development of Moodle system through designing and implementation of a new question type called "Highlight words" in this system. The idea of answering method to this question type is highlight word from a given clickable text.We used the following requirements to design and implement the proposals tools in this thesis : 32 bit windows7 operating system, 2.30 GHz Core i3 processor, router device, WAMP server, Moodle system (version 2.9) in English language, Mozilla Firefox web browser, Macromedia Dreamweaver 8 and First object XML Editor software
الصفحات الاولى:
مكان الجامعة: ذي قار
اللغة: الانكليزية
الجامعة: جامعة ذي قار - كلية التربية للعلوم الصرفة - قسم الحاسبات
الدرجة: ماجستير
الموضوع الدقيق: علوم الحاسبات
السنة: 2017
الموضوع العام: علوم الحاسبات
اسم المشرف: كاظم حسن كبان الابراهيمي
اسم المؤلف: نهلة فليح حساني الشويلي

تصنيف اورام الدماغ باستخدام الشبكات العصبية الاصطناعية

المستخلص: Accelerating the pace of scientific progress and that focus in the field of human service requirements is to provide daily health and service. Health aspect is one of the most important things of science that needs to be develop it because it has an important effect on human life. Medical imaging has become one of the most important factors in the treatment of human health. A large amount of information and data can be obtained about disease by different methods of Images acquisition techniques same like Magnetic Resonance Imaging (MRI), Computed Tomography (CT).The purpose of this thesis is to discover a way to detect the brain is to suggest a system to diagnose the brain whether it is normal or abnormal (contains a tumor) by using artificial neural network technology which contain many steps. The first step of detecting the brain tumor system is the input image to the system as digital data.The processing is the second step, which includes reducing noise and removing impurities of the brain image. So as the noise is removed by using median filter and wiener filter. After processing (filtration) image segmentation. Feature extraction is the techniques that is used to measure of difference properties of image segments, given the specific features as input to the artificial neural network classified (ANN).Seeded classified databases are due to the two types of brain image, (normal or abnormal).Samples have taken from a group of patients in AL - Husain Teaching Hospital disparate ages and both ganders, which was 100 samples ,80 of them were training samples and 20 were tested .The proposed system has proven successful of the diagnostic through the results obtained on the ratio of (100% in the training phase) and (100% in the testing phase
الصفحات الاولى:
مكان الجامعة: ذي قار
اللغة: الانكليزية
الجامعة: جامعة ذي قار - كلية التربية للعلوم الصرفة - قسم الحاسبات
الدرجة: ماجستير
الموضوع الدقيق: علوم الحاسبات
السنة: 2017
الموضوع العام: علوم الحاسبات
اسم المشرف: حازم باقر طاهر العلي
اسم المؤلف: نور حيدر داخل

تسريع ضغط الصور الكسوري باستخدام تقنيات مطورة Fast Fractal Image Compression using Adaptive Techniques

المستخلص: Fractal Image Compression (FIC) is one of the lossy techniques. In order for fractal compression image to be encoded is partitioned into non - overlapping blocks called ranges. From this range pool creates a new array called domain pool, the data of domain is array produced from taking an average of every four (2x2) adjacent elements in the range array, the domain is divided into overlapping blocks. Each block in range pool should be matched with every large number of blocks in the domain pool in order to find minimum error and recorded its best IFS approximate. The decoder process applies the determined IFS transformations on any initial image, and the process is repeated many times until reaching the attractor. In this thesis, it presents reducing the long encoding time of FIC without making significant sacrifice in the quality. In addition to the traditional fractal compression method, four IFS coding methods have been tested.The first method is speed up encoding phase by using moment features of the domain blocks with threshold , this method it compute the moment features of domain blocks only , during the matching process, compares the ratio factor of domain block with threshold, then compute the scaling (s), offset (o) coefficients and minimum error between range and domain blocks, and storing the optimal IFS coding , the results of this method with lenna image (4x4) block size, (the encoding time = 50.29 sec), (compression ration= 4.57 ) ,(PSNR=24.04), (RTR=33.42 ). The second method is speed up encoding phase by using the entropy technique of the domain blocks only , during the matching process, compares entropy value of domain block with threshold, and storing optimal IFS coding , the results of lenna image(4x4) block size, (the encoding time = 95.47sec), (compression ration= 4.47 ) ,(PSNR= 24.08) and (RTR= 17.60) . In the third method it merges the entropy technique with moment features of domain blocks only , during the matching process, compares entropy value and moments ratio factor of domain blocks with threshold and storing IFC coding, the compression results of lenna image (4x4)block size , (encoding time = 100.90 sec), (compression ration=4.47) ,(PSNR= 24.11) and (RTR=16.66) , the flaw in this method is the encoding time of 16x16 partitioning more than 4x4 and 8x8 partitioning. In the fourth method speed up encoding phase by use moment features of the range and domain blocks, in this method it computes the moment features of range and domain blocks, during the matching process, if the moments ratio factor of range and domain blocks are equal then compute scale(s),offset(o) and error (R) .storing best IFS coding. the results of lenna image(4x4) (encoding time = 114.02 sec), (compression ration= 4.47) ,(PSNR= 24.43), (RTR=14.74), the flaw in this method is the encoding time of 16x16 partitioning more than 4x4 and 8x8 partitioning. Matlab R2008a was used as a program to designed and implemented to achieve the coding and testing tasks. The environment used for our tests is a single PC with processor (core i3 CPU 2.53GHz) and 4.00 GB RAM .
الصفحات الاولى:
مكان الجامعة: ذي قار
اللغة: الانكليزية
الجامعة: جامعة ذي قار - كلية التربية للعلوم الصرفة - قسم الحاسبات
الدرجة: ماجستير
الموضوع الدقيق: علوم الحاسبات
السنة: 2016
الموضوع العام: علوم الحاسبات
اسم المشرف: حازم باقر طاهر العلي
اسم المؤلف: حيدر عباس محسن

خوارزمية موازنة الاحمال المقترحة في الحوسبة السحابية A Proposed Load Balancing Algorithm in Cloud Computing

المستخلص: Cloud computing considers an important paradigm that provides services and dynamic virtual resources to the consumers over the internet.One of the main challenges and important fields for research in the cloud computing environment is load balancing. So the main goal of this thesis is to establish an effective load balancing algorithm for task scheduling. In cloud computing environment, the demands are executed into the virtual machines (VMs) and in the execution, it must be avoided a situation some of the resources are under loaded states while there are resources overloaded or heavy while achieving less the execution time of the tasks andresponse time. In this thesis, we present the Load Balancing Decision Algorithm (LBDA) which aims to achieve load balancing for reducing the : Total completion time (Makespan), Response time and Total execution time of tasks in cloud computing environment.The mechanism of LBDA is based on three functions, first : calculating the virtual machine capacity, virtual machine load then determining VM states (Under loaded, Balance, High balance, Overloaded) based on comparing VM capacity, VM load and using three thresholds : threshold upper; threshold fair; and threshold lower. Second : estimating the time required to complete executing the task in each VM. Finally, making a decision to distribute the tasks among the VMs based on VM state and task time required. Where checked task time required into VMs under states and selecting the fastest VM, when there are more than one VMs have the same time to complete a task, LBDA assigns a task to VMs which has the largest capacity. When all VMs become (Balance or High balance) states, the tasks are distributed between VMs depending on the fastest execution. The proposed LBDA was compared with Max - Min, Shortest Job First and Round Robin algorithms. We applied many experiments with various VMs’ capacity and : A different number of tasks on a different number of VMs, The same number of tasks on a different number of VMs, and A different number of tasks on a different number of VMs.The performance evaluation results implemented in cloudsim toolkit 3.0.3 and the experiments demonstrate that our proposed LBDA outperformed to other algorithms by reducing the completion time of tasks, response time, andtotal execution time of tasks.
الصفحات الاولى:
مكان الجامعة: ذي قار
اللغة: الانكليزية
الجامعة: جامعة ذي قار - كلية التربية للعلوم الصرفة - قسم الحاسبات
الدرجة: ماجستير
الموضوع الدقيق: علوم الحاسبات
السنة: 2017
الموضوع العام: علوم الحاسبات
اسم المشرف: خلدون ابراهيم عارف
اسم المؤلف: اطياف ضاري برغش

مخطط يربط المفتاح بالقياسات الحيوية لحماية انظمة المعلومات A Biometric Key Binding Scheme for Information Systems Protection

المستخلص: Cryptosystems becomes an increasingly important feature as the most reliable tool in network and information security. However, while there are many forms of cryptosystems exist today a weak link of all systems is the secure management of the cryptographic key. And as a result of the growing interests in biometrics a new field of research has emerged, which is called "biometric cryptosystems". Within biometric cryptosystems the advantages of biometric authentication are introduced to generic cryptographic key management systems to enhance security.This work proposes a scheme to bind a cryptographic key with the face biometric by combining correlation filters based biometric recognition with a biometric key binding scheme with providing the variation tolerance, discrimination and security which are the most important requirements that apply to a cryptographic key retrieval using a biometric. In the proposed scheme the cryptographic key is generated independently of user's face image using Pseudo - Noise generator to produce a unique and long enough key (128 bits) for each user then this key is linked to the face image only through a secure block of data known as the 'protected record'. The correct key will only be derived via the interaction of this protected record with the correct user's face image during a live authentication process. The resultant key may be used in a system as cryptographic key or as a personal identification number (PIN) to overcome the need to carry, store, or remember keys for cryptosystems or any other application that are used (PIN).The proposed scheme performance has evaluated using FACE 94 facial database. The performance rate reached to 100% which is a perfect result for practical applications. The proposed scheme is implemented using (MATLAB 2008). It is executed for testing purpose on computer with processor of 1.80 GHZ dual core, i3 under Microsoft Windows 7 operating system.
الصفحات الاولى:
مكان الجامعة: ذي قار
اللغة: الانكليزية
الجامعة: جامعة ذي قار - كلية التربية للعلوم الصرفة - قسم الحاسبات
الدرجة: ماجستير
الموضوع الدقيق: علوم الحاسبات
السنة: 2016
الموضوع العام: علوم الحاسبات
اسم المشرف: كاظم مهدي الموسوي كاظم حسن الابراهيمي
اسم المؤلف: ابرار خلف الشريفي

Secure Email Message Using Genetic Algorithm - Based Elliptic Curve Cryptography Systems

المستخلص: Email is a service for exchanged messages between group of people (sender and receiver) using communication network. Nowadays people, companies, and business sectors are using email in the official communications. There are a lot of threats on the email service and the most importantly one is the eavesdropping. Some email messages are very important and must have a level of security during exchange of them.The current study uses hash function to add data integrity by applying Secure Hash Algorithm - 1(SHA - 1). This study uses Elliptic Curve Digital Signature Algorithm to add authentication and non - repudiation to the email message sender.Encrypt of an email message is a solution to overcome the eavesdropping. Hence, the attacker can obtain the email message but cannot read it without the key. The encryption algorithm, which is used, is Elliptic Curve Cryptography. This algorithm has a strong encryption, high level of security, and small key size compared to the RSA algorithm.The contributions of this thesis are : proposes a new method based on genetic algorithm to select the most effective parameters of the Elliptic Curve Cryptography (a,b); and proposes four encryption methods : updated symmetric Elliptic Curve Cryptography, modified Menzes - Vanston Elliptic Curve Cryptography, hybrid symmetric and asymmetric Elliptic Curve Cryptography, and hybrid Menzes - Vanston Elliptic Curve Cryptography and AlGamal Elliptic Curve Cryptography.The proposed methods are compared against previous techniques. It is found that these methods outperform the previous techniques in terms of the encryption/decryption processing time and the level of security.
الصفحات الاولى:
مكان الجامعة: البصرة
اللغة: الانكليزية
الجامعة: جامعة البصرة - كلية العلوم
الدرجة: ماجستير
الموضوع الدقيق: علوم الحاسبات
السنة: 2018
الموضوع العام: علوم الحاسبات
اسم المشرف: Haider M. Abdul - Nabi
اسم المؤلف: محمد حسن حالوب

Robust and High Capacity Data Hiding System Using Error Correcting Codes

المستخلص: اقترح هذا البحث تقنية متينة لاخفاء العلامة المائية والتي نستطيع ان نعالج من خلالها كمية كبيرة من البيانات مثل الصور ذات التدرج الرصاصي.لقد تم تحقيق موازنة بين كمية البيانات المخبئة وبين نوعية الصورة الحاوية للعلامة المائية.تهدف الخوارزمية الى جعل المتطفل يخفق في الوصول الى مكان المعلومات داخل الصورة وذلك من خلال التوزيع العشوائي لمكونات العلامة على كل الصورة. تم تطبيق الخوارزمية في مجال تحويل المويجة (Wavelet Transform) لما لهذا التحويل من فوائد عديدة والتي يمكن استغلالها في كبس الصور وكذلك في التطبيقات العملية للعلامة المائية. لقد تم تنفيذ البحث ايضا بطريقة جديدة وذلك باستخدام شفر تصحيح الخطا لتجاوز مشكلة فقدان البيانات اثناء عملية الكبس والكبس الاضافي الفاقد للبيانات. لقد تم استرجاع الصورة المخفية بشكل تام والنتائج العملية كانت مقنعة بسبب تشابه الصورة الاصلية مع الصورة الحاوية للعلامة المائية وصمود ومتانة العلامة امام الكبس الاضافي. اشارت النتائج العملية بعدم وجود تشويهات مرئية في الصورة المسترجعة حتى بعد 5 % من الكبس الاظافي علاوة على تعقيد اسلوب محاولة كشف العلامة. هذا يشير بان نظام العلامة المائية مقاوم اكثر الى هجمات الضغط ذو الخسارة العالية. | In this research, a robust watermarking system for images is proposed. The proposed scheme can handle a significantly large quantity of data such as gray scale images. A trade - off between the quantity of hidden data and the quality of the watermarked image had been achieved. The proposed algorithm aims to mislead the intruder and prevent the detection of the watermark due to the random distribution of the signature image on the entire image. The algorithm is applied in the wavelet transform domain. The wavelet transform has a number of advantages over other transforms that can be exploited for both image compression and watermarking applications. Therefore, it had been found that it is imperative to consider the wavelet transform domain for watermarking applications.1. Due to the lossy compression, some parts of the watermarking will be lost. For that the algorithm had been implemented with the new proposed approach using error correcting codes skill to overcome this drawback. The impact of different codeword lengths of BCH code is also investigated. The BCH code is effective against burst error. This approach has been compared with the case of embedding without using error correcting codes and satisfactory results were achieved, as the watermarked image was visually similar to the original. Experimental results indicated that are no visible distortions in the watermarked image, and the recovered signature is similar to the original signature even after 5% JPEG lossy compression quality factor. This indicates that the watermark system is more resistant to lossy compression attacks (JPEG).
الصفحات الاولى:
اللغة: الانكليزية
الموضوع الدقيق: علوم الحاسبات
الموضوع العام: علوم الحاسبات
اسم المشرف: منذر التكريتي قاسم زيدان
اسم المؤلف: نداء حسن عباس

معادلة تجريبية لتخمين سرعة ترسيب الجسيمات لجو مدينة بغداد EMPIRICAL RELATION TO ESTIMATE PARTICLE DEPOSITION VELOCITY OVER BAGHDAD CITY

المستخلص: ان الهدف من هذا البحث هو انشاء وتصميم نموذج رياضي لحساب سرعة ترسيب الجسيمات فوق مدينة بغداد وبستخدام قياسات لسرعة الرياح ودرجة الحرارة بالقرب من سطح الارض وعلى ارتفاع 20 متر. لقد بينت النتائج ان سرعة الترسيب تتناسب طرديا مع انصاف اقطار الجسيمات الكبيرة والتي هي اكبر من 1.5 مايكرومتر بسبب تاثير الجاذبية عليها, اما بالنسبة للجسيمات الصغيرة التي اقطارها اقل من 0.1 مايكرومتر تتناسب سرعة ترسيبها عكسيا مع انصاف اقطار هذه الجسيمات لكون تاثير الجاذبية عليها معدوم. اما بالنسبة للجسيمات التي تترواح انصاف اقطارها من 0.1 الى 1.5 مايكرومتر يحصل فيها ثبوت بسبب الوصول الى السرعة الحدية. وكذالك يمكن ان نستنتج ان اعلى قيمة لسرعة الترسيب تحدث في حالة الظروف المستقره واقل قيمة تكون في الظروف الغير مستقرة وفي الوسط حالة التعادل وهذا ينطبق مع الطبيعة الفيزيائية لميكانيكية الاستقرار في الغلاف الجوي وكذالك يمكن ان نستنتج من خلال الحسابات ان هنالك علاقة طردية مابين سرعة الترسيب والسرعة الاحتكاكية ولكنها تختلف باختلاف احجام الجسمات لكل حالات الاستقراريه ففي المديات الحجمية من 0.01 الى 0.3 مايكرومتر هنالك زيادة تناقصية لسرعة الترسيب مع زيادة السرعة الاحتكاكية حتى الثبوت عند المديات الحجمية من 0.3 الى 1 مايكرومتر بحيث يكون هنالك عدم تاثير لزيادة السرعة الاحتكاكية على سرعة الترسيب وبعد هذا المدى الحجمي والذي هوا 1 مايكرومتر هنالك علاقة طردية تزايدية لسرعة الترسيب مع زيادة السرعة الاحتكاكية حتى المدى الحجمي 30 مايكرومتر. اما بالنسبة لطول الخشونه فان تاثيرها يظهر فقط في حالة الاستقرار وعدم الاستقرار الجوي وهذا التاثير يكون قليل على سرعة الترسيب وتقريبا متساوي في كلا الحالتين حيث ان الزيادة في طول الخشونه تؤدي الى الزيادة في سرعة الترسيب. اما العلاقة مابين سرعة الترسيب وسرعة الرياح فهي علاقة عكسية زيادة سرعة الرياح سوف تعرقل من نزول الجسيمات وبالتالي تقلليل سرعة الترسيب وهذا التاثير يظهر فقط على الجسيمات الكبيرة الاكبر من 5 مايكرومتر. واخيرا تاثير درجة الحرارة الذي يدخل للموديل عن طريق الحركة البروانية فانه يكون قليل جدا ويهمل هذا التغير حيث وضع في الموديل تغير في درجة الحرارة من صفر الى 50 درجة سليزية ولم يحث سوى تغيير طفيف جدا وهذا لكل حالات الاستقرارية المتعادلة والمستقرة والغير مستقرة | AbstractThe aim of this research to make and design mathematical model and empirical relation for calculate deposition velocity of particles above Baghdad city by using data of wind speed and temperatures near the earth surface at the high 20 m. Result indicate deposition velocity have a direct relation with the large particles which have half diameters more than 1.5 micrometers because the effect of gravity on it, for the small particles the half diameters less than 0.1 micrometers have inverse relation with deposition velocity because the effect of gravity on it is neglected, As for particles has a half diameters from 0.1 to 1.5 micrometers there will be fix state because the reach to terminal velocity. also we will discover that high value deposition velocity will be happen in the case of stability, and the low value in the case of instability, and in the middle will be neutral and this similar to the physics natural of the mechanical saturation in the atmosphere. also will be cover from the calculation there is a direct relation between deposition velocity and friction velocity but they are different with the particles volume for all case of stability, in the volume range from 0.01 to 0. 3 micrometers there is decreasing in deposition velocity with increasing of friction velocity until fixation at the volume range from 0. 3 to 1 micrometers until there is no effect for the increase friction velocity on the deposition velocity, after this volume range 1 micrometers there is direct increase deposition velocity with increase friction velocity until range volume 30 micrometers . As for Roughness length the effect appears only in the case of stabile and unstable and this effect will be less on the deposition velocity and nearly equal in both case, because the increase in roughness length lead to increase deposition velocity. The relation between deposition velocity and wind speed the inverse relation, the increase of wind speed will prevent particles fall are lead to minimize deposition velocity and this effect appears only on the particles size more than 5 micrometers. Finally the effect of temperature appears in the model from the browin motion will be very latter and neglected this change, inter in this model change of temperature from 0 to 5 C0 there was a very later change and that for all case of stability ( stable, unstable and neutral).
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: ماجستير
الموضوع الدقيق: علوم الجو
السنة: 2015
الموضوع العام: علوم الجو
اسم المشرف: منعم حكيم خلف الجبوري
اسم المؤلف: هبة سعد حسن

تحليل قابلية التنبؤ المناخي للشرق الاوسط باستخدام انموذج ديميتر

المستخلص: في هذه الدراسة استخدمت طريقة نسبة الاشارة لحساب القابلية على التنبؤ المناخ الفصلي . وتعتمد هذه الطريقة على نظام تنبؤ المجموعة Ensemble Prediction System ((EPS . كما تم استخدام نوعين من البيانات الخاصة بالمركز الاوربي للتنبؤ بالطقس المتوسطة المدىEuropean Center For Medium Range Weather Forecast (ECMWF) وهما بيانات ديميتر والبيانات المعادة التحليل ERA - 15. اذ تتكون هذه البيانات من عدة مجاميع Ensembles وكل مجموعة تتكون من عدة افراد Members ،وتعتمد هذه البيانات على ملفات خاصة من اجل فتحها والتعامل معها. ولقد تبين من خلال هذه الدراسة ان القابلية على التنبؤ لانموذج ديميترتكون جيدة للعراق في حالة الارتفاع الجهدي لمستوى 850 hPa ،وللمناطق القريبة من البحر الاحمر خاصة السعودية في حالة درجة الحرارة الجهدية لمستوى 500 hPa. بينما تكون متوسطة في معظم منطقة الشرق الاوسط وتحديدا العراق للارتفاع الجهدي لمستوى 500 hPa ودرجة الحرارة الجهدية لمستوى 850 hPa و500 hPa. كما نجد ان القابلية على التنبؤ لانموذج الـ ERA - 15 تكون متوسطة في معظم منطقة الشرق الاوسط من ضمنها العراق. وان انموذج ديميتر اكثر كفاءة من انموذج الـ ERA - 15 في حساب القابلية على التنبؤ على المستوى الاقليمي regional فضلا عن كفاءته على مستوى العالم Global . | In this study the signal to noise ratio method has been used to count seasonal climate predictability which depend on ensemble prediction system .We use two type of data in this study, which are : Demeter data and Reanalysis of Data ERA - 15 belong to the european center for medium range weather forecast and these data consist of several ensembles, and every ensemble consists of several members. These data depend on special files to facilitate opening and dealing with it. The results show that the predictability for Demeter model is good for Iraq in case of geopotential height at 850 hPa level ,and for red sea regions especially kingdom of saudi arabia ,in case of potential temperature at 500 hPa level. While in the most of middle east regions, the predictability is moderate for potential height at 500 hPa level and potential temperature at 850,500 hPa level. The predictability for ERA - 15 model is found also to be moderate in most of middle east regions especially for Iraq. Finally, Demeter model is more efficient than ERA - 15 model in calculating the predictability for both regional and global regions.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: ماجستير
الموضوع الدقيق: علوم الجو
الموضوع العام: علوم الجو
اسم المؤلف: نور واثق عبد الكريم الشيخلي

تقييم تاثير التغير المناخي العالمي على درجة حرارة الهواء في العراق باستخدام نماذج المناخ Evaluating of the Impact of Global Climate Change on Air Temperature in Iraq using Climate Models

المستخلص: Global warming and climate change refer to an increase in average global temperatures. Natural events and human activities are believed to be contributing to an increase in average global temperatures. This is caused primarily by increases in “greenhouse” gases such as Carbon Dioxide (CO2). The aim of this research is to use simple climate mathematical models to investigate effects of various parameters, functions, and components of the climate system on the temperature rise. Also it aims toward the use of the output of complex climate models to explore the future rise of temperature over Iraq for the 21st century. The results indicated that the increase in diffusivity causes an increase in the heat flux towards the poles causing the temperature to increase in the polar regions and sub polar regions and to decrease in the tropics and subtropics regions. Solar radiation plays a major role in the climate system. It was found that a change of +/˗0.1 of its current value could led the Earth surface to be ice free/totally covered with ice. The results showed that changes in upward longwave radiation can mostly affect polar and sub polar regions. The effect of Hadley cell is to increase the heat flux towards the poles and therefore increasing temperature in these regions and reducing it in the tropics. The results for the simulation of land/ocean combinations for different initial temperatures showed that the combination of most amount of water cover was closest to the initial temperature for all initial temperatures and the combination of most land cover was the farthest distribution from the initial temperature. Analysis of the output of the Intergovernmental Panel on Climate Change (IPCC) models for Iraq showed that global warming will affect Iraq in this century. For the mid - century the temperature will be increased by 0.5 to 2.5 oC and summer months will be the most affected time of the year. The results suggested that by the end of the century temperature will be increased by 3.5 to 4.5 oC and also summer months will be the most affected time of the year. Comparison of the 16 models and three scenarios (B1, A1B and A2) of the IPCC Baghdad showed that for mid - century the scenario B1 gave the lowest increase of temperature for all months, while the scenarios A1B and A2 gives the highest increase of temperature for most of months for all models. For the end of century, it was found that in this period the scenario A2 gives the highest increase of temperature for most of the models, while scenario B1 give the lowest increase temperature for most of models.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: ماجستير
الموضوع الدقيق: علوم الجو
السنة: 2014
الموضوع العام: علوم الجو
اسم المشرف: قیس جمیل الجمیلي بدور یاسین حمود
اسم المؤلف: میلاء محمد كاظم الجبوري

Modeling the effect of virtual temperature on take - off and landing operations of aircraft

المستخلص: This Thesis focuses on the role of virtual temperature during Take - off and Landing performance, any increase in temperature or altitude means a decrease in the aircraft's optimum performance, so both of high temperature and high elevation airports, an airplane requires more runway to take off. Its rate of climb will be less (during take - off), its approach will be faster (during landing). The increase in temperature leads to a marked increase in radius of turn (during take - off and landing) but a tiny decrease in obstacle angle (during take - off) and a small increase in flare height (during landing).The effect of virtual temperature of five Iraqi airports (Mosul, Erbil, Sulaimaniyha, Baghdad and Basra), and the data base for an extended period was from January 2008 until the month of February 2014. Information was selected for weather report for certain days of the summer season (May, June, July, August and September), where the maximum temperature recorded was 50 ° C for airports Basra and Baghdad, the maximum temperature recorded during the period studied at the Mosul airport,48 ° C at the Erbil airport 44 ° C and Sulaymaniyah airport 43 ° C . Certain days of the winter season (December, January, February) were selected where the minimum temperature recorded the lowest, lowest temperature recorded in Basra airport 6° C, Baghdad airport 2 ° C, Mosul - 1 ° C, Erbil - 2 ° C and Sulaymaniyah - 8° C. The effect of virtual temperature was calculated for five Iraqi airports from comparing the most requirements affect (radius of turn, Distance and stalling velocity) in winter/summer with typical requirement (measured at ISA), the comparing use of actual values and their average during a case study in every airport, icy aerodrome which is considered as an extreme type and calculate its effect in Baghdad and Basra airport. Simulation software program shows us Perfect take - off and landing which are usually preceded by a deliberate planning for approaching the most appropriate velocities. The simulation which was edited is named R.O.T.A.L. (Requirements of Take - off and Landing).This simulation used a set of covering equations programed in visual basic and other programs of medi
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: ماجستير
الموضوع الدقيق: علوم الجو
السنة: 2014
الموضوع العام: علوم الجو
اسم المشرف: نعمة محسن لفتة الفتلاوي
اسم المؤلف: مهند توفيق امين

تقدير تاخير الانتشار المحتث في اشارات نظام تحديد المواقع العالمي بواسطة المكونات الجوية Estimation propagation delay induced in GPS signals by atmospheric constituents

المستخلص: عندما تنتقل الموجات الراديوية خلال الغلاف الجوي الارضي المتعادل , فان الاشارات الراديوية تتاثر بتغير معامل انكساره بصورة واضحة , والذي يتسبب بصورة ابتدائية في تاخير وصولها , وفي العادة هذا يشير الى التاخير الناتج من التروبوسفير . ان نظام تحديد المواقع العالمي (GPS) هو عبارة عن الملاحة الراديوية الفضائية .ان المستلم في نظام (GPS) يقوم بتزويد معلومات الموقع والوقت الدقيقين ولعدد غير محدد من المستعملين وفي كل الظروف الجوية , نهارا وليلا في اي مكان في العالم . ان (GPS) يستخدم ثلاثة ترددات والتي هي (L1 = 1.57542 GHz) , (L2 = 1.22760 GHz) و(L3 = 1.38105 GHz) . ان الهواء الجاف , بخار الماء , الجسيمات الجوية المائية والجسيمات الاخرى (التراب , الغبار والعوالق الجوية) في الغلاف الجوي تسبب تاخير في انتقال الموجات الراديوية .هذه التاخيرات يجب ان تكون موصوفة بدقة من اجل الحصول على الدقة الاعلى في المسح الارضي والتحسس النائي باستعمال اشارات نظام تحديد المواقع العالمي (GPS) . يركز الجزء العملي بصورة رئيسية على كيفية توضيح ونمذجة تاثيرات المكونات الجوية مثل الجليد , بخار الماء , الاوكسجين , الغيوم , المطر والثلج على ترددات (GPS) (L1 , L2 وL3) . النتائج توضح ان الجزء الحقيقي والجزء الخيالي لمعامل الانكسار المعقد للجليد يتزايد مع الزيادة في درجات الحرارة اما للماء فانها تنخفض مع الزيادة في درجة الحرارة , لكن بصورة عامة فان معامل الانكسار المعقد للماء يكون اعلى منه للجليد . كذلك فان قيم التوهين الناتجة عن قطيرات الغيمة النقية بواسطة رايلي هي اكبر من قيمها الناتجة عن قطرات المطر النقية بواسطة مي للترددات الثلاثة , وهذه القيم تتناقص مع الزيادة في درجة الحرارة وتزداد مع الزيادة في التردد . ان لكل من طيف بخار الماء والاوكسجين منطقتين تمتلكان اعلى قيم للتوهين (ان لكل من طيف بخار الماء والاوكسجين منطقتين تمتلكان اعلى قيم للتوهين ( GHz183 ,GHz 325 لبخار الماء وGHz 60 , GHz 118 للاوكسجين ) . ان تغير الطور التفاوتي (∅∆) في حالة المطر يحصل بواسطة قطرة المطر المفلطحة والتي لها محورين مختلفين وبسبب الاختلاف في تركيز قطرات المطر , ايضا فان (∅∆) لا تعتمد على درجات الحرارة لكنها تزداد مع زيادة التردد حيث تكون قيم (∅∆) deg/km 6 لـ (L1) , deg/km 5 لـ (L2) وdeg/km 5.4 لـ (L3) . بالاضافة الى اعتماد التوهين التفاوتي (∆A) في حالة المطر على شكل قطرة المطر وتركيز القطرات فانه يعتمد على درجة الحرارة والتردد . ان (∅∆) في حالة الثلج تحصل بواسطة الشكل غير المنتظم لجسيم الثلج وتعتمد على درجات الحرارة والتردد . ان (A∆) في حالة الثلج تمتلك قيم واطئة جدا في درجات الحرارة المختلفة والترددات المختلفة | When radio waves propagate through the earth’s neutral atmosphere, the radio signals are affected significantly by the variability of its refractive index, which causes primarily in the delay of the arrival, usually referred to as the tropospheric delay . The Global Positioning System (GPS) is a space - based radio navigation . The GPS system receiver provides exact location and time information for an unlimited number of users in all weather conditions, day and night, anywhere in the world. The GPS uses three frequencies that are (L1 = 1.57542 GHz , L2 = 1.22760 GHz and L3 = 1.38105 GHz) . Dry air, water vapor, hydrometeors and other particulates (sand, dust and aerosols) in the atmosphere introduce radio waves propagation delays. These delays must be properly characterized to achieve the highest accuracy in surveying and atmospheric sensing using Global Positioning System (GPS) signals . This work mainly focuses on the illustration of a model showing the effects of the atmospheric constituents such as ice and snow, water vapor , oxygen , clouds , rain on the GPS frequencies (L1 , L2 and L3) .The results show that the real and imaginary parts of complex refractive index for ice increase with the increase of the temperature and for water decrease with the increase of the temperature , but generally , the complex refractive index of water is higher than that of ice . Also , the attenuation values that are induced by pure cloud droplets by Rayleigh are higher than the attenuation values that are induced by pure water drops by Mie for the three frequencies , and these values decrease with the increase of the temperature and increase with the increase of the frequency . Each of water vapor and oxygen molecules have a small effect on radio waves in troposphere . The differential phase shift (∆∅) in case of rain is caused by the oblate rain drop that is has two different axes ,and because of the difference of the concentration of rain drops, also (∆∅) doesn't depend on the temperature but increase with the increase of the frequency where the values of (∆∅) are 6 deg/km for L1 , 5 deg/km for L2 and 5.4 deg/km for L3 . In case of rain , the differential attenuation (∆A) in addition to depend on the shape and the concentration of drops , it depends on the temperature and the frequency . In case of snow , the (∆∅) caused by the irregular shape of snow particle and depends on the temperature and the frequency . The (∆A) in case of snow has very low values in different temperatures and frequencies
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: ماجستير
الموضوع الدقيق: علوم الجو
السنة: 2014
الموضوع العام: علوم الجو
اسم المشرف: ضياء عزيز بلال
اسم المؤلف: فايز هلال صالح الزيادي

تصميم وتطبيق منظومة تعقيم المياه باستخدام الاشعاع الشمسي Designing and Implementing a Water Disinfection System by Solar Radiation

المستخلص: تم العمل بهذه الاطروحة لتصميم وتطبيق منظومة عملية تعمل على تعقيم ماء الشرب باستخدام الاشعة الشمسية المتوفرة في قطرنا بشكل واسع، وباقل التكاليف لاستخدامها في البيوت العراقية وخاصة تلك التي تقع في القرى والارياف والمناطق النائية. الخطوة الاولى كانت الاعداد لنظام بسيط لهذه المنظومة، والخطوة الثانية كانت تحضير الحاويات الملائمة لهذه المنظومة وتجهيزها بنماذج الماء الخام(الملوث) وتعريضه للاشعاع الشمسي.لقد تم اجراء اكتر من 25 تجربة لاختبار تاثير مختلف المتغيرات الجوية على عملية تعقيم ماء الشرب باستخدام الاشعاع الشمسي,وتاثير هذه المتغيرات على كفاءة قتل مجموعة البكتريا القولونية، القولونية البرازية والقولونية بالاشعاع الشمسي. هذه المتغيرات هي : درجة الحرارة، الاشعاع الشمسي، الوان حاويات المنظومة، المطر والغيوم والعواصف الرملية. وقد تم مقارنة نتائج هذه التجارب باستخدام الاشعاع الشمسي والحرارة مع نتائج التجارب التي استخدمت فيها الحرارة فقط.وقد كانت نتائج هذه التجارب كما يلي : 1 - ان قيمة الاشعاع الشمسي الساقط على مدينة بغداد للفترة من 22 مايس 2009 ولغاية 4 تموز 2010 ودرجات الحراة المسجلة عن طريق المحطة الانوائية والثرموميتر الموجودعلى سطح المنظومة، كانت طيلة هذه الفترة اعلى من الحد الادنى المطلوب لتعقيم الماء باستخدام الاشعاع الشمسي ,باستثناء ايام الشتاء المحددة بشهري تشرين الثاني وكانون الاول. والمعالجة خلال هذه الفترة كانت تتم عن طريق زيادة الفترة الزمنية لتعريض النموذج للاشعاع من 6 ساعات الى 48 ساعة.2 - اظهرت نتائج التجارب بوضوح تاثير عكورة الماء على عملي التعقيم باستخدام الاشعاع الشمسي,حيث يتم تركيد(ترسيب) الجسيمات الدقيقة العالقة قبل التعريض للاشعاع الشمسي، وبهذه الخطوة يتم التخلص من حولي 90% من العدد الكلي لجميع المجموعات من الكائنات الحية الدقيقة العالقة مع الجسيمات.3 - اظهرت نتائج التجارب الى ان هناك ترابط وتازر بين الاشعاع الشمسي ودرجة الحرارة، واظهرت احدى التجارب في الصيف انه قد تم قتل كل مجموعة البكتريا الموجودة في النموذج 100% يعد التعريض للاشعاع والحرارة معا، الا انه يم يتم الوصول الى هذه النتيجة بتعريض هذا النموذج للحرارة فقط.4 - عندما يكون الجو حارالاانه مصحوبا بعاصفة ترابية فانه لا يتم تعقيم الماء 100% في مثل هذه الظروف، وتكون المعالجة بزيادة الفترة الزمنية لتعريض النموذج من 6 ساعات الى 48 ساعة.5 - تم اجراء العديد من التجارب بعد تغيير الوان حاويات المنظومة واختبار كفاءة قتل البكتيريا بعد تغيير الالوان, وكانت النتائج كالتالي : الازرق(كفاءة عالية)، الاصفر(معتدلة) والاحمر (منخفض)الكفاءة.6 - اتضح من خلال التجارب ان موسم الصيف يظهر فيه اكبر عدد من انواع البكتيريا في نماذج الماء غير المعاملة(غير المعرضة للاشعاع)، اما موسم الشتاء فيكون فيه عدد انواع البكتيريا اقل. | The aim of this thesis is to design and implement a system for disinfecting drinking water by solar radiation with low cost so that it can be used in Iraqi houses, particularly, those located in suburban and rural areas. The steps of system include building the system, preparing the required water containers, collecting the infected water samples and exposing them to solar radiation. More than 25 experiments were conducted to test the effects of several variables on the process of water disinfection by solar radiation and the impact of each of these variables on the efficiency of the inactivation of the total coliform, faecal coliform and E.coli by the solar radiation. These variables include water turbidity, the amount of solar radiation, air temperature, dust storms, cloud formation, and rainfall. These experiments were compared with the inactivation of bacteria by heating (oven) only. Results indicated that the amount of solar radiation incident on Baghdad during the period from 22 March 2009 to 4 July 2010, and temperature recorded by the Weather Station and by the thermometer mount on the system was always more than the threshold value required for the inactivation, except during days of winter months of November and December due to low amount of solar radiation. This was overcome by increasing the time period of exposure to the solar radiation from 6 hours to 48 hours. The results of experiments showed clearly the effect of water turbidity on the disinfection processes by solar radiation. Settling infected water samples before exposing them to solar radiation has inactivated 90% of bacteria. Experiments conducted during summer, when solar radiation values are relatively high showed the percentage of bacteria inactivation was 100%, while disinfection by heat only did not reach that value. The conditions of dust storm occurrence, cloud formation, and fall of rain greatly affect the disinfection processes by solar radiation, since these atmospheric constituents reduces the amount of solar radiation reaching the Earth's surface. Results suggested that under such conditions, exposure time should be increased from 6 to 48 hours. Several experiments were performed to investigate the effect of the containers colors (wavelengths) on the bacteria inactivation. Three colors were selected; those are blue (short wavelength), yellow, and red. Results showed that the blue colored containers have the highest efficiency, yellow containers have moderate efficiency, and red containers have the lowest efficiency. Results also illustrated that infected water samples collected during summer have a larger number of bacteria that those collected during winter.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: دكتوراه
الموضوع الدقيق: علوم الجو
السنة: 2010
الموضوع العام: علوم الجو
اسم المشرف: حسن هاشم سلمان خليل مصطفى خماس
اسم المؤلف: عبد الوهاب حسين محمد علي العبيدي

تنبؤ احصائي لسرع الرياح لمحطات محددة في العراق Statistical Forecasting of Wind Speed for Selected Stations in Iraq

المستخلص: Wind speed is one of the most meteorological variables which has been changing rapidly with time. Due to the properties of wind speed such as non - stationarity, high fluctuations and irregularity. accurate forecasting becomes a challenge because, The wind speed is easily influenced by many factors, such as latitude, altitude, terrain, pressure, temperature. Therefore, The forecasting of the wind speed is important for many environmental, economic and meteorological applications. Due to the difficulties of the physical models and their non - availability, The Box - Jenkins ARIMA model has been used .Because, it is suitable tool to predict the wind speed and can also be used as an effective tool to get the missing data which existing within the time series of monthly mean wind speed. When Box - Jenkins ARIMA model has used, The ARIMA (15,1,10) model has determined as a suitable model for the monthly mean wind speed for studied stations in Iraqi after passing through the four stages of the model that include Identification of The Time Series, Estimation of The Model Parameters, Diagnostic Check of The Residuals and Model Adequacy and finally, The Forecasting. Many of the evaluation criteria have been used to check the accuracy of the best proposed prediction models by lowest values of each MAE and RMSE and MAPE and the highest values of the correlation coefficient (R2) and correlation coefficient (r), which confirmed the preference of ARIMA(15,1,10) for the monthly mean of wind speed but, This model could not applied on the daily mean of wind speed due to difficult in chose one best - fit model for all time series in all regions of Iraq. Because, The large variance of the wind speed during day and night and has not appeared clear correlation in all stations as shown in monthly data. The best solution is to take the difference of the non - stationarity time series from one lag to the next and then analyze this series after reaching to stationarity. The time series of daily wind speed need to take the difference once for the Baghdad station (d = 1) and twice for the Kirkuk station (d = 2) and three times for the Nasiriya station (d = 3) for reaching to stationarity. When ARIMA(15,1,10) model has been used, All the residuals were found within the confidence intervals and The error rate of using MAPE measure has been found near ( 4% ) for all studied stations in Iraq .
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: ماجستير
الموضوع الدقيق: علوم الجو
السنة: 2014
الموضوع العام: علوم الجو
اسم المشرف: بدور ياسين حمود العامري محمد احمد صالح ابو الطيب
اسم المؤلف: سرى ثامر ناصر

تحليل الانماط الزمانية والمكانية للاوزون فوق العراق nalysis of temporal and spatial patterns of ozone over Iraq

المستخلص: onthly and annual values of the total column ozone amount have been analyzed for five locations of Iraq for the period from 1979 to 2012 employing Total ozone Mapping Spectrometer (TOMS) data point and (1o × 1.25o ) grid data, It is found that ozone variation is function of latitude, where the higher values of total ozone column occurs at the northern Iraq which represented by Mosul location, it decreases gradually from northern location (Mosul) passing by middle region locations (Biji, Baghdad and Rutba) to southern location (Basra). The values of Total ozone column start to increase gradually from November to reach its maximum at March then it decreases gradually to reach its minimum values at October. The analysis of the spatial distribution of the monthly average of total ozone column for each month of the year has been made. It is found that the largest of total ozone column amounts occurs systematically over the northern regions during winter whereas in spring and early summer months the maximum values of total ozone column directed to the northwestern regions of the Iraq. Latitudinal gradients in total ozone column are very strong especially during winter, spring and early summer months. The spatiotemporal trend analysis has been made by converting the gridded data from time domain to spatial domain, it is found that the results show that the total ozone column trends was negative during most months of the year, whereas the spatial trend analysis of the second period of study (2005 - 2012) presented positive total ozone column during all months of the year except February and September which presented a negative trends and the overall presented positive trends varied from 0.1 to 2.3 DU / year. Finally the results of the two period trend analysis indicated that the ozonelayer may be responding as expected to the reducing on ozone - depleting substances imposed by the Montreal Protocol.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: ماجستير
الموضوع الدقيق: علوم الجو
السنة: 2014
الموضوع العام: علوم الجو
اسم المشرف: علي محمد عبد الرحمن الصالحي
اسم المؤلف: زهراء موسى حسن

تاثير درجة حرارة سطح البحر المتوسط على درجة حرارة الهواء السطحية والامطار لبعض المواقع في الشرق الاوسط The effect of Mediterranean Sea surface temperature on air surface temperature and rainfall for some locations in the Middle East

المستخلص: درجة حرارة سطح البحر تلعب دور مهم في التغير المناخي لانها تؤثر على درجة حرارة الهواء مباشرة فوق السطح ومعدل التبخر للماء والذي يؤثر بدوره على درجة حرارة الهواء وتكوين الغيوم والامطار. لذلك دراسة درجة حرارة سطح البحر مهمه في حل المشاكل للظواهر الجوية والبحرية ونظام المناخ للارض. يهدف هذا البحث الى دراسة تاثير تغيرات درجة حرارة سطح البحرالابيض المتوسط(SST) على درجة حرارة الهواء السطحية(T2M) والامطار(TP) لمنطقة الشرق الاوسط خلال الفترة .(1980 - 2009) البيانات المستخدمة في هذه الدراسة تم الحصول عليها من المركز الاوربي وتم عمل ثلاث شبكات للمتغيرات لايجاد العلاقة بين SST وT2MوTP ب استخدام طريقتين للتحليل الاحصائي. ففي الجزء الاول من الدراسة تم استخدام طرق التحليل الاحصائي مثل السلاسل الزمنية ومعامل الارتباط, وتم اختيار ثلاث مواقع (نقاط) على الشبكة في البحر المتوسط واربع مناطق في الشرق الاوسط (بغداد, عمان, دمشق, بيروت).النتائج اظهرت ان التغيرات في درجة حرارة سطح البحر لها اكبر قيمة للميل في شهر تموز (0.06) للنقاط الثلاثة واقل قيمة كانت في الفصول الانتقالية, في شهر نيسان كانت (0.01) للنقطتين الاولى والثالثة, في شهرتشرين الاول كانت قيمة الميل (0.04) في النقطة الثالثة. اما اعلى قيمة للميل لدرجة حرارة الهواء السطحية في الشرق الاوسط فكانت في شهر تموز (0.06) في مدينتي بغداد ودمشق وكانت اقل قيمة في شهر نيسان (0.006 - ) في مدينة عمان. بالنسبة لقيمة الميل للامطار فكانت اعلى قيمة في عمان وبيروت (0.3) خلال شهري كانون الاول وشباط على التوالي, واقل قيمة للميل كانت في بغداد (0.27 - ) خلال شهر كانون الاول. بينت النتائج ان درجة حرارة سطح البحر لها اكبر تاثير على درجة حرارة الهواء السطحية في شهر تموز, بسبب ان معامل الارتباط كانت له اعلى قيمة (0.58), (0.48), (0.50), (0.56) للمدن بغداد وعمان ودمشق وبيروت على التوالي خصوصا مع النقطة الاولى. اقل قيمه خصوصا للنقطتين االثانيه والثالثه فكانت في شهر نيسان, (0.007 - ), (0.08 - ), (0.08 - ), (0.08 - ) للمدن بغداد وعمان ودمشق وبيروت على التوالي.ولوحظ انه لاتوجد علاقة بين درجة حرارة سطح البحر والامطار للمناطق الاربع لان معامل الارتباط له قيم قليله في كل المواسم المطرية.في الجزء الثاي من الدراسة فتم استخدام طريقة التحليل بواسطة الدالة التجربيبة المتعامدة (EOF) للتغاير المكاني واخذت اول نمطين للـEOF الاول والثاني (EOF2, EOF1) وطريقة التحليل بواسطة (PC) للتغاير الزمني للنمط الاول (PC1). استخدمت شبكتين للنقاط للبيانات, الاولى تمثل شبكة SST لمنطقة البحر المتوسط والشبكة الثانية تمثل شبكة ((T2M,TP لمنطقة الشرق الاوسط وبقدره تميز 0.50 x 0.50 وقسمت فترة الدراسة الى فترات تمثل كل عشر سنوات.النتائج بينت ان نسبة التغاير المكاني لدرجة حرارة سطح البحر للـEOF1 ودرجة الحرارة السطحية كانت 97% و95% من التغاير الكلي على التوالي , وهذا يشير الى وجود علاقة محتملة بينهم, بينما التغاير المكاني للامطار سجلت اقل قيمة خلال فترة الدراسة.اما التحليل بواسطه التغاير الزمني بواسطه PC للـ SST فقط لوحظ وجود دوره قوية لها عشر قمم كل عشر سنوات من فترة الدراسة. | Sea surface temperature plays an important role in the climate change, because it affects the temperature of the air immediately above the surface, evaporation rate of water, cloud formation and precipitation. Therefore, the study of sea surface temperature is fairly essential for solving many meteorological and oceanographic problems and climate system of the earth. The aim of this thesis is to study the effect of sea surface temperature (SST) variation of Mediterranean Sea on air surface temperature (T2M) and rainfall (TP) in Middle East during the period (1980 - 2009). The data used in this study obtained from the Europe center (ECMWF) and made three grids of the variables in order to determine the relationship between SST and (T2M, TP) by using two statistical analysis methods. In the first part of study, statistical analysis technique used such as time series and correlation coefficient, and select three location (points I,II,III) on the grid of Mediterranean sea and four locations on Middle East (Baghdad, Amman, Damascus, Beirut). The results show that, The variation of SST has the highest value of trend in July (0.06) for the points I, II, III and the lowest value was in the transition season, in April was (0.01) for point I, III, in October was (0.04) for point III. While the highest value of trend for T2M in Middle East was in July (0.06) in Baghdad and Amman city and the lowest value in April ( - 0.006) in Amman city. For the value of trend of rainfall, the highest value was in Amman and Beirut (0.3) in December and February months respectively, and the lowest value of trend was in Baghdad ( - 0.27) in December month. The results show that the SST has the largest impact on T2M in July, because the correlation coefficients has the highest value (0.58), (0.48), (0.50), and (0.56) for Baghdad, Amman, Damascus and Beirut respectively especially for point I. The lowest value of especially for point II, III, in April was ( - 0.07), ( - 0.008), ( - 0.008) and ( - 0.008) for Baghdad, Amman, Damascus and Beirut respectively. And notes there is no relation between SST and TP for the four locations, because the correlation coefficient has small value in all rainfall months. The second part of the study use the Empirical orthogonal function (EOF) for the spatial variance and take the first two EOF (EOF1, EOF2) mode, and principle component analysis (PCA) tool for the temporal variation of (PC1) mode. Two grids of points have been used for the data; the first one represents the SST grid of Mediterranean Sea area and the second one represents the (T2M, TP) grid of Middle East of 0.50 x 0.50 and the period of study divided into periods every 10 years. The results show that the percentage of spatial variation of EOF1 for SST and T2M was 97% and 95% of total variance respectively, that indicate to have possible relationship between them while the spatial variance of TP record the lowest value in the period of study. The analysis made by the temporal variance of PC for SST show it has strong cycle with 10 peaks every 10 years of the period of study.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: دكتوراه
الموضوع الدقيق: علوم الجو
السنة: 2014
الموضوع العام: علوم الجو
اسم المشرف: منعم حكيم خلف الجبوري
اسم المؤلف: حنين حاكم عبد الرضا عباس

تاثير البقع الشمسية على بعض المتغيرات المناخية في العراق The Effect of Sunspot Numbers on Some Climate Variability over Iraq

المستخلص: ان دراسة العلاقة بين النشاط الشمسي مع المتغيرات المناخية من العلوم المهمة والتي ترتبط ارتباطا مباشرا بالانسان وبيئته . في هذا البحث تم دراسة العلاقة بين النشاط الشمسي (دورة البقع الشمسية) مع بعض العناصر المناخية مثل الامطار ودرجات الحرارة وذلك بالاعتماد على سنين طويلة من الرصدات والبيانات . تم استخدام معاملات الارتباط الخطية لاختبار درجة الارتباط بين اي متغيرين . تم استخدام طريقتين لدراسة هذا البحث : الاولى هي دراسة العلاقة بين الدورات الشمسية (ما يقارب 11دورة شمسية ) مع كل من ظاهرة (NAO و(ENSO وقد تبين بان التغيرات طويلة المدى لل NAO)) تتناسب تناسبا عكسيا مع دورة البقع الشمسية عند نهاية القرن التاسع عشر وبداية القرن العشرين بمعامل ارتباط مقداره (0.65 - ) , بينما كان التناسب طرديا للفترة (1940 - 2010) وبمعامل ارتباط مقداره (0.75) ومن جهة اخرى تم دراسة العلاقة بين ( NAOو(ENSO مع درجات الحرارة والامطار للمحطات الثلاث موصل - بغداد - البصرة وقد تبين بان علاقة ال(NAO) مع درجة الحرارة عالية بشكل عام في الشتاء بينما كانت العلاقة ضعيفة في فصل الصيف للمحطات الثلاث وتقل تلك العلاقة كلما اتجهنا جنوبا . اما علاقة (NAO) مع الامطار كانت متذبذبة بين معاملات ارتباط عالية واخرى واطئة. اما فيما يتعلق بالعلاقة مع ال(ENSO) فهي ضعيفة عموما للمحطات الثلاث. الطريقة الثانية استخدام تقنية Continuous Wavelet Transformation) ) ذو الابعاد الثلاث ( three dimensions)من خلال برنامج MATLAB لمعرفة مدى الدورية periodicity للنشاط الشمسي مع المجموع السنوي للامطار للفترة (1910 - 2000) ومع درجات الحرارة للفترة 1871 - 2008 للعراق. وقد اشارت النتائج الى ان للبقع الشمسية ثلاث فترات periodicity رئيسية 11، 21 و33 سنة ، بينما كان للعناصر الجوية دورات صغيرة (2 - 9 ) سنة بالاضافة الى نفس الدورات اعلاه (11، 21،33 ) سنة. تم تطبيق المتوسط المتحرك moving average طبقا لتلك الدوريات periodicities حيث تبين ان للنشاط الشمسي علاقة جيدة مع الامطار ، بينما كانت علاقة النشاط الشمسي مع درجات الحرارة غير واضحة او متغيرة مع كل من الزمان والمكان | The study of the relation between solar activity with the climate elements is one of the important science which closely related with the human and his environmental. Relationships between solar activity (sunspot cycles) with some climate elements such as precipitation, Air temperature was the primary aim of this thesis, biased on many years of observations and using linear correlation coefficients to examine the relations between two variables. The methods of this research were organized in two domains as follows : The first domain : Studied the relation between solar cycles (for about eleven cycles) with (NAO) and with (ENSO). The main results were the long - term variations of NAO are negatively correlated with sunspot activity at the end of the 19th and the beginning of the 20th century, with a correlation coefficient of ( - 0.65), whereas positively correlated for the period (1940 - 2010), with a correlation coefficient of (0.75), links (NAO and ENSO) with air temperature and precipitation have been also studied for three stations, Mosul, Baghdad and Basra. The main results showed that the NAO is closely correlated with air temperature in winter season (higher than summer) for the three stations, but this correlation relatively decreased toward south of Iraq. The relation between NAO and precipitation was oscillated between high and low correlations. The relations between the ENSO with air temperature and with precipitation were not obvious for the three stations. The second domain : is using continuous wavelet transformation by MATLAB technique. The relations between the solar cycles with annual precipitation for the period (1910 - 2000), air temperature, for the period (1871 - 2008) have been studied for Iraq. The results indicated that the sunspot cycles have three main periods, around 11, 21 and 33 year, while the studied climate elements had small periods (3 - 7) as well as the 11, 21, 33 years. After applying moving average according to the periodicities that found by continuous wavelet transformation, relations between solar cycles were closely related to the annual precipitation. Whereas the correlation of solar activity with air temperature was found to vary with place and time
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: دكتوراه
الموضوع الدقيق: علوم الجو
السنة: 2012
الموضوع العام: علوم الجو
اسم المشرف: عوني ادوار عبد الاحد بدور ياسين حمود
اسم المؤلف: بيداء جعفر حسن

تاثير شدة الاضطراب على اداء توربين الرياح Effect of Turbulence Intensity on Wind Turbine Performance

المستخلص: The ongoing depleting of oil and gas reserves, combined with the growing concerns about global warming, has made it inevitable to seek alternative resources of energy. To substitute oil produced energy and eventually minimize atmospheric degradation, renewable energy resources have increasingly become attractive and have been widely used. Therefore, this study focuses on one of the most important resources of renewable energy which is wind energy.Wind speed and direction data of Sulaymaniyah Province (airport station) in the north of Iraq in (2012) measured with 10 seconds time interval, were used to calculate wind potential in the site. Wind speed values with 10 seconds time interval are important to calculate wind turbulence intensity. Mean wind speed and standard deviation with (1, 10, and 60 minutes) time intervals were calculated, together with wind speed distribution, wind direction distribution, wind shear, and turbulence intensity; also, the appropriate class of wind turbine was identified.The impact of meteorological parameters (turbulence intensity, and wind shear) on the performance of wind turbine has been calculated using a MATLAB programming language, which was designed and implemented for this study.Results show that the turbulence intensity is the most significant parameter due to its major effects on the useful life time of a wind turbine. In addition, ambient turbulence intensity was determined, and the turbulence generated by wind turbines was calculated, this type of turbulence is called effective turbulence intensity (Ieff). It was found that wind turbine class (C) is a suitable choice to be installed at the study site (Sulaymaniyah airport station).VIAlso, results show that wind shear is a very important concept for wind turbine developers and installers, since a small difference in wind speed can lead to large difference in power output of a wind turbine. This can be achieved either by calculating wind speed at different heights using equivalent wind speed or by calculating wind speed at hub height using power law. It can be concluded that using equivalent wind speed to evaluate the site gives better calculation of mean wind speed available at that site than wind speed calculated at hub height only. In addition, shear exponent calculation as a function of height is more accurate than its assumed constant value (0.14), in power density estimation.Moreover, wind speed data, of Baghdad Province (Al - Mustansiriyah University meteorological station) in the middle of Iraq in (2008) measured with 15 minutes time interval, were used to calculate the characteristic turbulence intensity of small wind turbine, and monthly mean turbulence intensity. It was found that wind turbine class (B) is the best choice in Al - Mustansiriyah University site. In addition, the highest values of monthly mean turbulence intensity at Baghdad (Al - Mustansiriyah University) were obtained during November, and January, while the lowest values were in June, and July.Finally, wind data were analyzed using Weibull distribution function with its parameters (scale and shape), which were calculated using three analytical methods. Results show that the maximum likelihood method (MLM) gives the best calculation for Weibull parameters in both Sulaymaniyah airport and Al - Mustansiriyah University stations.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: دكتوراه
الموضوع الدقيق: علوم الجو
السنة: 2015
الموضوع العام: علوم الجو
اسم المشرف: عوني ادوار عبد الاحد محمد احمد صالح
اسم المؤلف: باسم عبد السادة محمد الكناني

نمذجة ابذار الغيوم الدافئة بواسطة قطيرات محلول كلوريد الصوديوم Modeling of Warm Cloud Seeding Using NaCl Solution Droplets

المستخلص: Clouds has a crucial role in the dynamic and thermodynamics of the atmosphere. Precipitation from clouds is of vital importance for human life and activity. Cloud seeding, a form of weather modification, is the attempt to change the amount or type of precipitation that falls from clouds, by dispersing substances into the air that serve as cloud condensation or ice nuclei, which alter the microphysical processes within the cloud. The usual intent is to increase precipitation (rain or snow), but hail and fog suppression are also widely practiced in airports. The aim of this study is to develop and implement a numerical warm cloud models to simulate microphysical processes within clouds and investigate the effects of seeding process on the formation of raindrops. Results of the modeling the effects of solute on the formation of cloud droplets suggested that the super saturation is decreased by solutes and critical super saturation value depends on the activity of the solute. The results also indicated that Urea is the best solute for decreasing super saturation, as compared with other materials. Bulk modeling of warm clouds showed that updraft, fall speed, radius of cloud element, and surface temperature are the most important factors affecting the microphysical processes within the cloud parcel. An increase in these parameters can lead to an increase in the fallout from cloud. Simple model of warm cloud droplet suggested that updraft, initial drop radius, and liquid water content play an important role in the growth of cloud drop and rain formation. Numerical simulation of warm cloud seeding by salt solution showed that growth of most drops depends on seeding density value, the rate of growth of the cloud drop increase with increasing seeding density in a nonlinear way. The results illustrated that the radius of the large drop plays an important role in growth process while very small radius of small droplets has almost negligible effects on the growth process. It was found that rainfall is increased when seeding density is increased from 0 (the case of no seeding). The results also showed there is an optimum value for seeding density that gives the relatively largest amount of rainfall. Beside seeding density, the updraft radius of the cloud plays an important role in the formation of rain. Therefore the proper seeding density to be used depends on the updraft radius of the cloud
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: دكتوراه
الموضوع الدقيق: علوم الجو
السنة: 2015
الموضوع العام: علوم الجو
اسم المشرف: رشید حمود النعیمي قیس جمیل الجمیلي
اسم المؤلف: اصداف عبد الامیررعید

دراسة الاشعاع طويل الموجة الخارج فوق العراق باستعمال بيانات AIRS Study of Outgoing Longwave Radiation Over Iraq Using AIRS Data

المستخلص: Outgoing longwave radiation (OLR) is a thermal energy represents total upward radiation from the Earth - Atmosphere system towards space. Clouds and greenhouses gases trapped and absorb certain wavelengths of OLR and radiated back towards the Earth, this led to adding an amount of heat to the atmosphere. Variation in OLR values would be influenced Earth’s climate system by increasing or decreasing the average temperature of the Earth's surface. The present thesis involves analysis the spatiotemporal distribution of the outgoing longwave radiation (OLR) and developing an OLR estimation models. Dataset acquired from polar orbit satellite Aqua and its instrument the Atmospheric Infrared Sounder (AIRS). The study was carried out using data collected from January 2003 to December 2016 which covered a region [W : 37.5, S : 28.5, E : 49.5, N : 38.5] in a grid of resolution of 1º×1º. The 13 - years data from 2003 to 2015 were used for climatology and for establishing relationships in the developed models, multiple linear regression (MLR) and Artificial Neural Network (ANN)because the suitability of the technique to provide estimates, while the data of the year 2016 was employed to investigate the estimation capacities of these models of monthly - average OLR value in Iraq. The spatiotemporal distribution of monthly averaged values of OLR for 13 years period showed that Winter season have the minimum average values, about (270 15.8) Wm - 2. Start from Spring season OLR levels become increasingly intense and reach (306 16.2) Wm - 2. Summer season became more intense when compared to previous seasons, specifically over the southern parts of Iraq and dominate the highest OLR overall observed average values. These values reached (351 16.2), (360 14.5), (355 12.9) Wm - 2 for June, July and August respectively. As Autumn season start, the reduction of overall average OLR values start. The minimum average values reached in November with a (283.6 12.3) Wm - 2. The results also showed a zonally relationship between OLR and latitude. The spatial variance of OLR values were indicates an indirect zonally relation between OLR and latitude.Different observed meteorological parameters, including (Surface temperature (ST), Relative humidity (RH), and Cloud fraction (CF)) were offered as the input variables for modeling ANN and MLR to get OLR values. For the entire period, these three meteorological parameters were highly correlated (R= 0.980) with measured OLR. Furthermore, satellite data were used in three different locations over Iraq (Mosul, Baghdad and Basrah). Estimations of OLR values were evaluated by using several statistical bases. Comparisons among the three selected cities in test data (the year 2016) showed close agreement between the estimated OLR and measured OLR from AIRS. Mosul city at the north of the study area showed the best statistical performance indicators with the lowest root mean square error (RMSE) of (4.4966 and 1.3853) and highest correlation coefficient (R) of (0.9929 and 0.9993) for the two models (MLR and ANN) respectively, indicating model's efficiency and accuracy. Statistical analysis in term of β (regression constant) showed that surface temperature (1.823 to 2.311) tended to contribute significantly to high OLR values.The estimated results showed a satisfying performance for the ANN model when compared to the MLR model. These results obviously indicate the advantage of using the satellite AIRS data and both of MLR and ANN models to investigate the impact of the atmospheric meteorological parameters on OLR values on cities and country. Finally, the MLR model is used to map the estimated monthly average of OLR over Iraq.
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية - كلية العلوم - قسم علوم الجو
الدرجة: ماجستير
الموضوع الدقيق: علوم الجو
السنة: 2017
الموضوع العام: علوم الجو
اسم المشرف: علي محمد الصالحي
اسم المؤلف: صفاء عبد الرزاق عبد الحسين

Application of Approaches of Mass Customization and its effect Competitive Advantages An Analytical Study for Wassit state Company for Textile Industries - Kut Factory

المستخلص: Describe mass customization system as the main of excellence and achieve sustainable competitive advantage and high profitability, also research based on the idea of substantial that the constant change in the needs and desires of customers divers mean intensification of the conflict in the field of competition in the business environment , which generates pressure on companies led to inevitability of the adoption of new technologies and new trends in production , represented by (mass customization system ) in order to achieve competitive advantage thereby increase profits the research was based on two variables interact with each other to form the frame of mind to him , are (mass customization approaches as the depended variable, the research initiate of problem expressed introduced a number of questions aimed at answering her knowledge of the theoretical aspects of these variables being one of the modern application topics , and then diagnosed effect adoption of mass customization in achieving competitive advantage in the wassit state company for textile industries / knitting factory and because of importance of these approaches and the need for adoption at the factory , which achieve thus competitive advantage . The study chapters include theoretical coverage of problem , the researcher depended on information in the literature of subject and accumulated knowledge in this area . As the research include applied aside based on key assumption and sub assumption specialized department including diagnosis of correlation between the mass customization approaches and competitive advantage , while the other section diagnosise singled relationship with the impact of the application of those approaches to achieve competitive advantage. Wassit state company for textile industries - knitting factory was chosen as a site to conduct research and researcher used variant statistical tools of analysis and processing of data and information using statistical system( spss).The research style was a prospective study - analytical being comprehensive analysis style and deep for problem. The researcher reach to the fact that the existence of relations correlation effect between the variables , and researcher presented a set of recommendation s that serv the factory , as if they were taking them based on the conclustions that have been reached , it was most notably the need to adopt factory mass customization a pproaches and need to take to achieve competitive advantage
الصفحات الاولى:
مكان الجامعة: بغداد
اللغة: الانكليزية
الجامعة: الجامعة المستنصرية
الدرجة: ماجستير
الموضوع الدقيق: ادارة اعمال
السنة: 2013
الموضوع العام: الادارة والاقتصاد
اسم المشرف: احمد عبد اسماعيل الصفار
اسم المؤلف: حامد كاظم معن

استقصاء قلف شجرة الكالبتوس كمانع تاكل للفولاذ الكربوني X52 في الاوساط المختلفة للانابيب الناقلة للنفط الخام Investigation The Bark Of Eucalyptus Tree As Corrosion Inhibitor For Carbon Steel X52 In Different Media Of Crude Oil Pipelines

المستخلص: In the oil and gas industry, the crude oil pipelines which made of low carbon steel suffer from internal corrosion. The corrosion operation is originally related with the presence of the wastewater mixed with the crude oil, especially when it is accompanied by hydrogen sulfide, carbon dioxide, elemental sulfur, inorganic salts, organic acids, and bacteria. Corrosion inhibitors injection in the oilfield is a most common and beneficial method for prevention the pipelines internal corrosion. Because of a high cost and toxic nature of the chemical corrosion inhibitors which used presently in oil industry, it is necessary to promote a less expensive and environmentally acceptable inhibitors, natural plants can be treated as a perfect sources for this purpose.This study investigate the internal corrosion of low carbon steel pipelines in fluid environments, as well as prepare and use natural and locally available plant ( the bark of eucalyptus tree) as a natural corrosion inhibitor, and compared the new inhibitor with a chemical inhibitor used by Missan Oil Company (MOC) in terms of the cost, toxicity, availability and performance.Some experiments were achieved to estimate the performance of a new inhibitor, one of these tests include corrosion measurement by simple immersion in crude oil within and without of inhibitors which added in different amounts 30, 40, 50, and 60 ppm , where the best inhibition efficiencies which get when added the inhibitors in a critical amounts or closest to it, since for the aqueous extract (EB - A) the inhibition efficiency reached (94.4) and (86.71)% at 300 and 323K respectively, and for diethyl ether extract (EB - D) reached (82.87) and (84.6)% at 300 and 323K respectively, while the chemical inhibitor (CRW) which used by MOC reach to (84.21) and (88.73)% at 300 and 323K respectively.optical microscopy examination have been conducted to evaluate the corrosion nature where it show a clear difference in the topography of the immersed samples surface after add the inhibitors at two temperatures.Another tests was achieved to evaluate the corrosion behavior such as potentiostatic polarization and open circuit potential tests in wastewater, since the inhibitor efficiency at 313k reached (88.21)% when add a 60ppm from the EB - A inhibitor to the wastewater in Tafel extrapolation, while it reached (74.91)% when add a 30ppm from the EB - D inhibitor.Several tests was achieved such as FT - IR spectra and using a chemical reagents to detection the presence of many active groups and the presence of tannins, phenols and alkaloids in the Eucalyptus Bark (EB).The results show , that the new corrosion inhibitor is not only equivalent to a chemical inhibitor, but have greatly improvement properties such as : high efficiency , low cost , non - toxic , easily to product, and nonpolluting as compared with chemical inhibitor which is considered toxic and cancering inhibitor.
الصفحات الاولى:
مكان الجامعة: بابل
اللغة: الانكليزية
الجامعة: جامعة بابل - كلية هندسة المواد - قسم هندسة المعادن
الدرجة: ماجستير
الموضوع الدقيق: هندسة المعادن
السنة: 2017
الموضوع العام: هندسة الانتاج والمعادن والمواد
اسم المشرف: كاظم فنطيل السلطاني
اسم المؤلف: زينب فؤاد حمزة الشريفي

استقصاء الخواص الفيزيائية والميكانيكية لنحاس الومينا متدرج وظيفيا Investigation Of Physical And Mechanical Properties Of Cu/Al2O3 Functionally Graded Materials

المستخلص: One of the most important smart material is the functionally graded materials, which had more increasing attention in different engineering applications.In this study, five - layered stepwise Cu/Al2O3 as functionally graded materials have been prepared from copper powder with five percentage of alumina powder as (5, 10, 20, 30, and 40 Wt%) by using powder metallurgy technique. Mixing of copper (34.32 ?m) and alumina (1.439 ?m) powders for two hours and then several disk sample with dimensions (14mm diameter and 10mm thickness) and cylindrical specimens with (18mm diameter and 27 height) have been compacting at different compacting stresses (550, 650 and 750 MPa). However, sintering of specimens for three hours at 850?C under vacuum about has been achieved.Several physical tests such as porosity, electrical resistance and thermal conductivity, X - ray diffraction, X - ray Fluorescence and Particale size analysis have been achieved. Furthermore, Microstructure and mechanical tests such as hardness, compression, double shear and dry sliding wear have been done for preparing samples from composite and functionally graded material.Numerical modeling using finite element analysis by ANSYS software has been presented for copper/alumina joints and compare with copper/alumina functionally graded materials.From the several experimental results, it is clear that the best compacting pressure was 650 MPa is determined by measuring green density at different compacting pressure, hardness increased with the increasing additive percentage of alumina, hardness resultschange in each layer by producing functionally graded materials (FGM) according to the percentage of the harder constituent (i.e. Al2O3) from 53 to 113 HV at compacting pressure 650 MPa, While the shear strength decreases with alumina increased from 72 MPa for layer one to 28 MPa for layer five at compacting pressure 650 MPa. The Wear rate increases as the time and load is increased. The wear resistance increased with increasing contain of Alumina. Results from the numerical modeling, it is clear that residual thermal stresses gradually decreased from the interface to the edges of functionally graded sample whereas in Copper/Alumina joint there is very high thermal residual stress in the joint interface.
الصفحات الاولى:
مكان الجامعة: بابل
اللغة: الانكليزية
الجامعة: جامعة بابل - كلية هندسة المواد - قسم هندسة المعادن
الدرجة: ماجستير
الموضوع الدقيق: هندسة المعادن
السنة: 2017
الموضوع العام: هندسة الانتاج والمعادن والمواد
اسم المشرف: عبد الرحمن كاظم عبد علي
اسم المؤلف: رؤى حاتم كاظم

امثلية عمليات اللحام باستخدام مصفوفة التضارب Optimization Of Welding Processes Using Confusion Matrix

المستخلص: Welding is a materials joining process in which two or more parts coalesced at their contacting surfaces by suitable application of heat and/or pressure.The proposed system consist of three stages : - First stage : preparing the actual samples from the previous research. These stage have multi tests (i.e, residual stress, fatigue life, impact energy, hardness and tensile strength) - Second stage : Translated the result of previous stage depending on speed of welding and heat input. The mechanical properties was related to the heat input and the temperature of the processes of welding. The quantity of the heat input was increased when the speed of welding was slow and heat input decrease when the speed of welding was high, this high heat input led to form coarse grain and this led to decrease the mechanical properties.Third stage : generated software system used different types of error measures, this software include two phase, the first phase is to estimate the error between the actual and predicted tests. While the second phase is to verification of the result phase on the person correlation measures, and this phase show high correlation among welding processes. In general these correlation lied from +1. The verification occur base on the measures of confusion matrix, (i.e SSE, MSE, RMSE ,MAPE, MPE and MAE ).The system satisfy the following results (Accuracy equal 84.37%, True positive (TP) equal 86.66 % and Precision equal 96.2% ).
الصفحات الاولى:
مكان الجامعة: بابل
اللغة: الانكليزية
الجامعة: جامعة بابل - كلية هندسة المواد - قسم هندسة المعادن
الدرجة: دبلوم عالي
الموضوع الدقيق: هندسة المعادن
السنة: 2015
الموضوع العام: هندسة الانتاج والمعادن والمواد
اسم المشرف: حيدر الجبوري
اسم المؤلف: حسين خليل برهان

تاثير معدل التبريد على خواص سبيكة Ag - Cu - Sn Effects Of Cooling Rate On Roperties Of (Ag - Cu Sn) Ternary Alloy

المستخلص: Dental fillings is widely used because of good mechanical properties and low cost but also was one of the more fillings topic of discussion and it studied continuously.The objective of this research is studing the effect of the cooling rate on the phases and properties of amalgam. two alloys were prepared by two types of casting (die casting and sand casting) with fixed percentage of tin, copper, silver and zinc for both alloys respectively about (7.5gm, 6.25gm , 10.75gm , 0.5gm).The process done by using an electric furnace in an inert gas atmosphere of argon and alloys thermally treated at a temperature (400C?) for a period of four hours for the purpose of homogenization phases alloys. And then it was studying the microstructure using an optical microscope. And using X - ray diffraction to determine the phases in alloys.The phase evaluation showed that the phases in the amalgam alloy (die alloy) has ? (Ag3Sn) , ? (Cu3Sn), and one other phase ? (Cu6Sn5) and the phases in the amalgam alloy (sand alloy) has ? (Ag3Sn) and ? (Cu3Sn). Then alloys have been converted into powder using a ball mill. The powder was treated thermally output for temperature (100C?) for a period of three hours atmosphere vacuum to remove internal stresses.The amalgam manufactured according to the ADA specification No.1 where he was mixing 0.8gm from each of the mercury and the powder for 30 seconds mined device and then put the dough, resulting in the mold of Teflon and sheds them straining compression amount (14MN / m2) for a period of 85 seconds still stress after that, the sample isextracted from the mold after the half - hour and placed in a glass chamber at a temperature of 37 ± 1C?.Microstructure of the amalgams were studied primarily by x - ray diffraction, optical microscopy.The phase analysis of two amalgams shows two phases; ?1, ?.studied the mechanical properties (tensile, compression, creep, dimensional change, hardness) and the result was that all properties effected with the change of the colling rate.It was conducted two types of corrosion tests are testing the open circuit (OCP) and potentiodynamic polarization in industrial saliva solution at a temperature of 37 ± 1C?.
الصفحات الاولى:
مكان الجامعة: بابل
اللغة: الانكليزية
الجامعة: جامعة بابل - كلية هندسة المواد - قسم هندسة المعادن
الدرجة: دبلوم عالي
الموضوع الدقيق: هندسة المعادن
السنة: 2017
الموضوع العام: هندسة الانتاج والمعادن والمواد
اسم المشرف: حيدر حسن جابر جمال الدين
اسم المؤلف: جمان حيدر ساجت
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