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تصميم وتنفيذ لنظام توصيات Design and Implementation for Recommender System

اسم المؤلف: زينه حسين فهد
اسم المشرف: طه سعدون باشاغا
الموضوع العام: علوم الحاسبات
السنة: 2010
الموضوع الدقيق: علوم الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Recommender systems have been introduced to provide a solution to navigating the huge volume of information already available and growing at an explosive rate. The amount of information available in electronic form, such as news, movies, books, advertisements and other online information is overwhelming us. Recommender systems are computerbased techniques that can be utilized to efficiently provide personalized services in many e - business domains.In this thesis, recommender system has been designed by mixing two main types of recommender systems (content based on personal profile and collaborative based). This type of system producing recommendations for its users in two stages. In the first stage, searching about active user's neighborhood is done to compute the similarity with the active user. The similarity is computed in two steps, the first step is to compute personal similarity using content based technique, depending on the personal features only. The second step is a conditional step that is if the user has enough rating then the similarity computed using collaborative filtering technique depending on the user ratings (rating similarity) in addition to personal similarity computed by the first step. In the second stage a list of new items is recommended from highly rated items by nearest neighbor users, with or without predictions on the acceptance of the list by the user.The content based part in which a personal similarity is computed a weight for each personal feature is required. So in this work, a survey has been made to obtain initial value for impact ratio (weight) for the effectiveness of each feature. Then the computation of these ratios is updated from time to time according to the given new users information.These updates are made according to Mean Absolute Error (MAE) between the real ratings and prediction of ratings

نظام محادثة فوري لشبكة اتصالات محلية مع بعض سمات الامنية LAN - Based Instant Messaging System with Some Security Aspects

اسم المؤلف: مروة سعد ملكي القس
اسم المشرف: عبیر متي یوسف جمال محمد كاظم
الموضوع العام: علوم الحاسبات
السنة: 2008
الموضوع الدقيق: علوم الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Instant messaging is a form of online, real time form of communication between two or more people based on typed text. IM system has grown rapidly among network users. But most of existing instant messaging systems have severe security problems, people want to retain their privacy and communication should not copy or modified by a third party. This thesis presents the design and implementation of a secure instant messaging system. It achieved security objectives such as data integrity and confidentiality through encryption. It ensures that the conversation is only read by intended recipient. The name of the proposed system is chosen to be SIMSM (the acronym for SIMple Secure Messenger).SIMSM is designed for local networks. Based on client - server connection, it enables users to send and receive secure instant messaging between them. No internet connection is required. Easily in sending and receiving text messages. It supports standard messaging features such as private chat, group chat (conference), message notification and encryption. The primary constituting modules are : Registration Module which identifies users to the system; Login Module which allows users to access the system; Sign - In Problem Module that deals with forgetting the identification (ID) and password problem; Private Chat Module that enable private chat between online users; and Conference Chat Module that enable more than one online user to chat with each others.The proposed IM system has been evaluated according to two important factors in instant messaging : security and time consuming. Many test cases were taken to show that SIMSM is quite suitable for secure chatting service.The proposed secure instant messaging had been established using windows API functions with Java platform version 6.0.0.105 programming language.

تمييز الارقام الهندية اعتمادا على طريقة هيكلية Hindi Number Recognition Based On Structural Approach

اسم المؤلف: هدى حمدان علي
اسم المشرف: بان نديم ذنون يونس
الموضوع العام: علوم الحاسبات
السنة: 2013
الموضوع الدقيق: علوم الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: يعتبر التمييز صفة اساسية للطبيعة البشرية وكذلك الكائنات الحية, توجد عدة تطبيقات عملية لتمييز الانماط. مثلا : في مجال تمييز الاحرف والارقام المطبوعة او المكتوبة باليد مثل قراءة العنوان البريدي بصورة اوتوماتيكية , قراءة الوثائق , تمييز لوحات تسجيل السيارات وغيرها من التطبيقات. في هذا البحث تم تصميم نظام لتمييز الارقام الهندية المطبوعة والمكتوبة باليد. النظام المقترح, استخدم لتحقيق هدف هذا البحث لتمييز الارقام الهندية (0,1,2,3,4,5,6,7,8,9) التي تستخدم عادة من قبل السكان العرب.لتحقيق هذا الغرض تم تنفذ عدد من المعالجات الاولية على الصورة المدخلة هذه المعالجات تضمنت عدة عمليات مثل ازالة الضوضاء, تحويل الصورة الى صيغة ثنائية, تقطيع الصورة (عزل الارقام), تنحيف الارقام .بعد هذه العمليات تم استخلاص الصفات لكل رقم واعتمادا على هذه الصفات تمت عملة التمييز.النظام فعال مع الارقام المطبوعة والمكتوبة باليد. ببساطة النظام يعتمد على تحديد عدد ومواقع النقاط الطرفية لكل رقم وهذا يمثل الخاصية الرئيسية للتمييز. خمس خصائص فقط قد اضيفت عندما كان هناك تشابه بين الارقام (لهم نفس عدد ومواقع النقاط الطرفية) تم فحص النظام على عدة انواع من الخطوط وباحجام مختلفة وكانت نسبة التمييز لـ 13 نوع من الخطوط هي 100% كما اظهر النظام نتائج مشجعة وممتازة مع 600 من النماذج المكتوبة باليد والتي تم كتابتها من قبل اشخاص مختلفين وباعمار مختلفة كما تم الفحص على نماذج مع حالة الدوران للارقام وحالات خاصة غير نظامية لبعض الارقام مثل (9,5) وكانت نسبة التمييز 98,1%. ان هذه النتائج تؤكد فاعلية الطريقة الهيكلية بتميز الارقام الهندية. | Recognition is regarded as basic attribute of human beings, as well as other living organisms. There are many practical applications of pattern recognition, such as : in the area of recognition of printed and handwritten letters and numbers in reading postal addresses automatically, reading documents, car plates recognition and others applications. In this research, printed and handwritten numerals recognition system is designed.The proposed system is used to improve the aim of this research for recognizing Hindi numerals (0,1,2,3,4,5,6,7,8,9), that are usually used by Arabs. To achieve this objective; a preprocessing for the entered image is executed. This preprocessing includes operations such as : noise removal, binarization, segmentation, thinning, then feature extraction is executed, finally the recognition is done depending on the previous steps and based on structural feature extraction method.The system is effective on both printed and handwritten numerals. It simply depends on determining number of terminal points and its positions for each numeral in its different shapes, that represent the main feature for recognition. Only five features are added when there is similarity between numerals (have the same number of terminals and position). Different fonts with different sizes are tested and the result of the recognition rate of 13 printed font type is 100%, excellent recognition results are obtained for 600 handwritten numerals samples written by different people, numerals with rotation state, and irregular samples for some numeral like (9, 5), recognition rate was 98.1%. these result emphasize the efficiency of structural method in recognizing Hindi numerals

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

اسم المؤلف: هبة سعد حسن
اسم المشرف: منعم حكيم خلف الجبوري
الموضوع العام: علوم الجو
السنة: 2015
الموضوع الدقيق: علوم الجو
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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).

تحليل قابلية التنبؤ المناخي للشرق الاوسط باستخدام انموذج ديميتر

اسم المؤلف: نور واثق عبد الكريم الشيخلي
الموضوع العام: علوم الجو
الموضوع الدقيق: علوم الجو
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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.

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

اسم المؤلف: میلاء محمد كاظم الجبوري
اسم المشرف: قیس جمیل الجمیلي بدور یاسین حمود
الموضوع العام: علوم الجو
السنة: 2014
الموضوع الدقيق: علوم الجو
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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.

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

اسم المؤلف: مهند توفيق امين
اسم المشرف: نعمة محسن لفتة الفتلاوي
الموضوع العام: علوم الجو
السنة: 2014
الموضوع الدقيق: علوم الجو
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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

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

اسم المؤلف: فايز هلال صالح الزيادي
اسم المشرف: ضياء عزيز بلال
الموضوع العام: علوم الجو
السنة: 2014
الموضوع الدقيق: علوم الجو
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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

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

اسم المؤلف: عبد الوهاب حسين محمد علي العبيدي
اسم المشرف: حسن هاشم سلمان خليل مصطفى خماس
الموضوع العام: علوم الجو
السنة: 2010
الموضوع الدقيق: علوم الجو
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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.

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

اسم المؤلف: سرى ثامر ناصر
اسم المشرف: بدور ياسين حمود العامري محمد احمد صالح ابو الطيب
الموضوع العام: علوم الجو
السنة: 2014
الموضوع الدقيق: علوم الجو
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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 .

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

اسم المؤلف: زهراء موسى حسن
اسم المشرف: علي محمد عبد الرحمن الصالحي
الموضوع العام: علوم الجو
السنة: 2014
الموضوع الدقيق: علوم الجو
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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.

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

اسم المؤلف: حنين حاكم عبد الرضا عباس
اسم المشرف: منعم حكيم خلف الجبوري
الموضوع العام: علوم الجو
السنة: 2014
الموضوع الدقيق: علوم الجو
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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.

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

اسم المؤلف: بيداء جعفر حسن
اسم المشرف: عوني ادوار عبد الاحد بدور ياسين حمود
الموضوع العام: علوم الجو
السنة: 2012
الموضوع الدقيق: علوم الجو
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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

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

اسم المؤلف: باسم عبد السادة محمد الكناني
اسم المشرف: عوني ادوار عبد الاحد محمد احمد صالح
الموضوع العام: علوم الجو
السنة: 2015
الموضوع الدقيق: علوم الجو
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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.

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

اسم المؤلف: اصداف عبد الامیررعید
اسم المشرف: رشید حمود النعیمي قیس جمیل الجمیلي
الموضوع العام: علوم الجو
السنة: 2015
الموضوع الدقيق: علوم الجو
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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

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

اسم المؤلف: صفاء عبد الرزاق عبد الحسين
اسم المشرف: علي محمد الصالحي
الموضوع العام: علوم الجو
السنة: 2017
الموضوع الدقيق: علوم الجو
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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.

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

اسم المؤلف: حامد كاظم معن
اسم المشرف: احمد عبد اسماعيل الصفار
الموضوع العام: الادارة والاقتصاد
السنة: 2013
الموضوع الدقيق: ادارة اعمال
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
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

تاثير اضافة الكالسيوم على البنية المجهرية والخواص الميكانيكية لسبيكة Al - Cu - Mg Effect of Ca Addition On The Microstructure And Mechanical Properties of Al - Cu - Mg Alloys

اسم المؤلف: نور صباح توفيق
اسم المشرف: منذر محمد راضي
السنة: 2014
الموضوع الدقيق: هندسة المعادن
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: في هذه الرسالة تم دراسة تاثير اضافة عنصر الكالسيوم بنسب مختلفة ) 3.0 المجهرية والخواص الميكانيكية لسبيكة) المنيوم - نحاس - مغنيسيوم ( , حيث تم انتاج هذه السبائك باستخدام والتي تتضمن )المعاملة المحلولية, )? السباكة الرملية وعوملت حراريا باستخدام المعاملة ا | In this thesis ,the effect of pure Ca element addition in different percents of (0.3,0.6,0.9%) on the mechanical properties of Al - Cu - Mg alloy were studied.The Alloys were produced using sand casting and heat treated using T6 which involve [solution treatment , quenching , artificial aging ], aging process were carried out at 220? C for different periods of time ranging between (5min to5hr).Also the work involves a study on the effect of Ca addition on both grain size as well as the resulting phases before and after heat treatment, samples were examined using optical microscope, Scanning Electron microscope ,X - Ray diffractometer and image - J to estimate the average grain size.The results of hardness and tensile tests for 0.6% Ca and 4hr aging shows the best response as compared to the other alloys. The hardness and strength values have been changed from (78.29HV)(110.57Mpa) during (30min)at 220?C for non - Ca content alloy to(125.9HV)(164.2Mpa) for 0.6%Ca alloy. X - Ray diffraction , results shows the basic phase that forms is Al2CuMg (S??, S? phase) which is considered as the main strengthening phase in AL alloys, and it was found that Ca addition leads to form (Al4Ca) and (Al2Ca)which delay the alloy response to precipitation hardening by delaying the formation of (S)phase. SEM images showed a large and small dimple structure and broken or cracked Al - Ca compounds particles.This indicates that the fracture was ductile fracture in the Al matrix and brittle in these compounds ,.Also presence of microvoids (porosity) on the fracture surface is formed at the interfaces between Ca compounds and Al matrix enhanced the crack propagation through their center. The presence of the secondary phases precipitates (Al2CuMg ,Al2Ca and Al4Ca) in the fracture surface also contributed to ameliorate the mechanical properties by increasing the bonding of the matrix and reduced the ductility.Also Ca addition in the range of (0.3 - 0.6%) gives rise to grains refining ,While increasing Ca content up 0.9%wt coarsing the grains, which leads to decrease the hardness and tensile strength, From these results the decrease in tensile strength with increasing Ca content over 0.9% seems to be attributed to the reduction in elongation caused by the occurrence of micro porosity due to Ca addition.

تخطيط مسار نقطي خال من الاصطدام لروبوت ممفصل ذا خمس درجات حرية Point - To - Point Free Collision Path Planning of 5 DOF Articulated Robot

اسم المؤلف: محمد عبد الرحمن غفور
اسم المشرف: تحسين فاضل عباس
السنة: 2014
الموضوع الدقيق: هندسة الانتاج
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: ان الهدف الرئيسي من هذا البحث هو ايجاد مسار لمفاصل الروبوت وللماسك النهائي في الروبوت خلال حركة الماسك من نقطة البداية الى نقطة الهدف المراد الوصول اليها خلال حيز مؤتمت بدون الاصطدام مع العوائق الموجودة في بيئة الروبوت اعتمادا على الحل العلوي لاذرع الروب | The main objective of this research is to find a path for the robot joints and gripper from the given start point to the desired goal point without collision with the obstacles which exist in the robot environment depending on the robot links upper solution. This research will investigate the problem of path planning for a 5 axis articulated robot, operating in an environment with obstacles whose boundaries are enveloped by a spherical shape. The path planning approach has been developed in the robot joint space and consists of five phases : The first phase is using Bezier, Hermit, B - spline and NURBS curve techniques considering their control points weight not constant. The second phase is to generate a sufficient number of intermediate points in Cartesian space along those curves. The third phase converts the coordinate of the generated intermediate points from its Cartesian space into joint space and move the robot gripper along the generated path. The fourth phase screens the generated four Bezier, Hermite, B - Spline and NURBS paths in order to choose the best one. The fifth phase is developing the chosen path by using proposed algorithm to improve the selected path.Both forward and inverse kinematics solutions for the robot links using Denavite - Hartenberg representation are important step to determine the manipulator's joint angles and Cartesian coordinates, that assists generating the required path which has been derived in this work.Matlab program has been used as an assistant program to analyze, sketch and implement the algorithms of forward kinematics, inverse kinematics and path planning.This work will not be limited to theoretical studies or simulations, experiments have been run with various tests, on "educational robot" Lab - Volt R5150 to assess which path is the better ability in avoiding the obstacles. The method applies to robots in a fixed and known environment. A number of experiments have been carried out to test the ability of the robot arm to reach its goal without collision It’s found that Bezier curve was the chosen path because it was the better obstacle avoidance and shorter path.

دراسة سلوك البلى الترددي لمواد مركبة ذات اساس من سبيكة المنيوم / sic تحت ظروف الانزلاق الجاف والرطب A Study On The Reciprocating Wear Behavior of Aluminum Alloy / SiC Composites Under Dry And Wet Conditions

اسم المؤلف: عتبة حسين علوان
اسم المشرف: احمد علي اكبر اكبر
السنة: 2014
الموضوع الدقيق: هندسة المعادن
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: تم في هذا البحث دراسة معدل البلى لاحدى سبائك الالمنيوم ((AA2024) (Al - Cu - Mg ومواد مركبة عن طريق تصنيع جهاز بلى ترددي تبعا للمقياس العالمي ( ASTM G133) ذو ترتيبة المسمار على المستوى (Pin on Flat) لمتغيرات مختلفة (الحمل المسلط , النسبة الوزنيه لدقائق كا | In this work the wear rate of one of aluminum alloys (Al - Cu - Mg) (AA 2024) and composite materials, has been studied by manufacturing a reciprocating wear device according to the International Standard (ASTM G 133 Pin on Flat) for different variables (applied load, weight percentage of (SiC) and sliding speed) under dry and wet (lubrication) conditions. Stir casting method has been used to prepare a composite material by using vortex technique to force the particles inside the molten metal (Al - alloy) and to distribute them regularly. The composite materials reinforced with different weight percentages of SiC (3, 6, 9, 12 wt%) are used. The base alloy and composite materials samples were tested to investigate the microstructure, and phases using optical microscope and Vickers hardness, wear rate, and the worn surfaces by using scanning electron microscope (SEM). From the results of microscopic examination it is found that the microstructure of alloy matrix was fine dendrites, in addition to the SiC particles that distributed near homogenously in the alloy matrix. The hardness test results showed that, the increasing of the weight percentage of (SiC) leads to increase the hardness, and the highest value of hardness was found at 12wt% SiC. Also the results showed that the wear rate increases with applied load for all weight percentage of reinforced particles (SiC).With increasing the load, more wear tracks, deep, and closed paths are formed and severe wear happens under dry condition but the lubrication case has less effect than dry case.It was shown that wear rate of both base alloy and composites under various conditions, increases with increasing of applied load and sliding speed but the wear rate decreases with increasing the SiC wt% in composite.Statistical method using software (Minitab 16) was used to study the effect of wear rate for both the base alloy and composite material by using three variables; applied load (X1), silicon carbide proportion (X2), sliding speed (X3), with five levels of each variable. It is concluded that the optimum weight loss under dry case was 0.0014g, The combined effect of variables and the wear rate was obtained and which variable are more influential, as shown in the equation below : D = 0.056703 - 0.002164 X2 - 0.000282 X3+ 0.000017 X1 X3 +0.000010X2 X3 While under lubrication case that the optimum weight loss was 0.0037g and the combined effect of variables and the wear rate was obtained and which variable are more influential, as shown in the equation below : L= 0.009607 + 0.002825 X1 - 0.002375 X2 + 0.001100 X3 + 0.001664 X3 2 + 0.004700 X1 X3 + 0.002700 X2 X3 The applied load (X1) and sliding speed (X3) have the largest effect on wear rate.

السحب العميق المتعدد المراحل للاقداح السداسية Multistage Deep Drawing of Hexagonal Cups

اسم المؤلف: صبيح سلمان داود
اسم المشرف: وليد خالد جواد
السنة: 2014
الموضوع الدقيق: هندسة الانتاج
الدرجة: دكتوراه
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: The aim of this work is to design and manufacturing a multistage (three stages) deep drawing dies to produce cylindrical and hexagonal cups of (43,33.1,26.8)mm diagonal diameter through two methods. The first method by drawing the hexagonal cups directly by using hexagonal orifice die from a flat sheet (blank) of (80mm) diameter and (0.7) mm sheet thickness for (1006 - AISI) hot rolling low carbon steel material.The second method by redrawing a cylindrical cups of (43,33.1,26.8) mm outer diameter (produced previously by a cylindrical orifice die) in to hexagonal orifice die which transform (convert) these cylindrical cups into hexagonal cups of (43,33.1,26.8)mm diagonal diameter.For all stages of drawing hexagonal cups, wall corner radius of die (0.7, 4)mm, with punch and die profile radius of (4 and 8) mm and drawing speed of (50, 200, 500) mm/min were used to study the effect of these parameter on drawing forces, cup wall thickness, strain distribution over the cup wall and surface defect of the cup wall.A commercially finite element soft ware (ANSYS 11.0)was used to perform the numerical simulation for cylindrical and hexagonal cups in three stages of drawing process. A comparison between theoretical (simulation) and experimental results lie within average of (15 - 20%), and the agreement is good in the first stage.The results shown that excessive metal flow ,maximum thinning of cup wall and maximum strain occurred at corner radius of (0.7) mm and at drawing speed of (500mm/min )for hexagonal cup produced directly from flat sheet.The results shown that the best thickness distribution and strain distribution over the cup wall, better cup wall surface (less surface defects) and lowest drawing force was with percentage (63.8%,45.4%,74.1%) respectively occurred when transform (converting) the cylindrical cup into hexagonal cup with wall corner radius of die (Rc= 4)mm in three stages.

دراسة زاوية تعشق العدة في عمليات التفريز Studying Tool Engagement Angle In Milling Process

اسم المؤلف: ليث فاضل شاكر
اسم المشرف: ليث عبد الله محمد
السنة: 2014
الموضوع الدقيق: هندسة الانتاج
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: هذه الاطروحة تعنى بدراسة تاثير زاوية تعشيق العدة بالمشغولة على ستراتيجيات ونتائج عمليات التفريز بالعدد ذات النهايات المسطحة. تم تصميم نموذجين (CAD model) باستخدام برنامج (Solid work 2013) الاول على شكل كونتور خارجي والاخر على شكل بوكيت داخلي وبعد ذلك تم | This work focuses on the effect of controlling tool engagement angle (TEA) on the milling process planning and the results of end milling operations. Two CAD models has been designed by using Solid Work 2013 software, then G - code have been generated and simulated by using Surfcam V5 software with (Fanuc post processing). AL7075 - T6 alloy has been used for its high machinability, dry machining (no coolant) has been done on 3 - axes milling machine (C - tek) available in the University of Technology Training and Workshop Center.Feeds, speeds and other machining parameters (axial and redial depth of cut) have been selected according to machining handbooks recommendations. Machining of workpieces has been accomplished by using two techniques (two types of tool - path), first one was conventional tool - path machining (contour parallel tool - path), and the second was by using TRUEMILL technique (true engagement controlled tool - path) by Surfcam V5. Thirty experiment have been designed, four of them have been failed, ten have been accomplished and the others neglected for reasonable causes as it will be discussed. Finally a comparison between the two techniques has been made focusing on machining time, material removal rate, cutting temperature and surface roughness. The results confirm that TEA control leads to reduce machining time, we have a time reduction in about (80%) for contour machining and (57%) for pocket machining. Cutting heat was under control though the feeds and the axial depths of cut went higher, also by controlling tool engagement angle we skipped the cause of failure of some experiment in conventional tool - path machining. Surface roughness was not that affected by controlling tool engagement angle, the minimum surface roughness in hand is (0.43 µm), it is higher than the best result of a previous work for the same material by 50%.

دراسة تجريبية حول مسحوق حبيبات النحاس ذات الحجم النانوي باستخدام الترسيب الكهربائي المصحوب بالامواج الفوق صوتية Experimental Study of Nanosized Copper Powder Using Sonoelectrodeposition Process

اسم المؤلف: حيدر ياسر ثامر الياسري
اسم المشرف: محمد جاسم كاظم عدنان شمخي جبر
السنة: 2014
الموضوع الدقيق: هندسة المعادن
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: عملية الترسيب او التحليل الكھربائي تعتبر من الطرق التصنيعية الرئيسية التي تستخدم لانتاج مختلف الاشكال والاحجام (ضمن المدى الميكروي) من حبيبات مسحوق معدن النحاس والتي تستخدم لاحقا بواسطة تكنولوجيا المساحيق لانتاج اجزاء محددة. ايضا استخدمت ھذه الطريقة بمد | Electrolytic or electrodeposition process is considered a main way to produce many shapes and sizes (micro range) of copper powder to be used in powder metallurgy process. It is used broadly to deposit copper coatings with nanosized grains, but it is rarely used to produce nanosized particles of copper. Reaching this goal is highly dependent on the optimum design of the parameters of electrodeposition process.This work aims to study the important variables that most affect the electrodeposition process outputs. These variables are : copper sulphate pentahydrate salt concentration CuSO4.5H2O (1, 5.5, and 10) g/l, cathodic current density (12.5, 25 , and 37.5) mA/cm2, ultrasonic (20 KHz frequency) vibration amplitude (5%, 20%, and 35%) from the maximum amplitude (1 ?m), and amount of sulphuric acid H2SO4 (H2SO4 concentration > 97%) in electrodeposition cell (0.05, 0.10, and 0.15) ml/l. The study of effects of these variables is concerned with size of resultant powder particles, also their effect on the purity, morphology, and shapes of particles is studied, and the crystallinity of particles is also covered.The design of experiment (DOE) approach is applied here through Taguchi design of experiments, to manage and analyze the results and study the specific effects of each. The arrangement of variables’ levels is done using the setup of (Taguchi L9).The analysis of experiment tests of the study of electrodeposition process to get copper nanoparticles showed that all variables have effect on the size of resultant copper particles, but in different ways and degrees. The mean particle size of all samples is about 86 nm. It was found that the increasing of concentration of copper sulphate salt (1, 5.5, and 10) g/l had a negative on the increasing the size of copper particles in the range (71, 69, and 117) nm.While the increasing of cathodic current density (12.5, 25 , and 37.5) mA/cm2 had an effect of decreasing the particle size of copper in the range (114, 75, and 68) nm. The case was the same for increasing of amplitude of ultrasonic vibration, where increasing it (5%, 20%, and 35%) caused decreasing in the particle size in the range (97, 92, and 68) nm. And the effect of acid amount (0.05, 0.10, and 0.15) ml/l was multiple because it decreased the particle size first and increased it later in the range (90, 65, and 102) nm. The amount of effect of each variable on the process was calculated using specific equations of Taguchi design. It was found that the current density has the bigger effect (35%) on the resultant particle size (it minimized the size). The salt copper concentration has the second effect (34%) (it maximized the size), and thirdly the acid concentration effect is 19% (it had multiple effect on the size).Finally the ultrasonic vibration has 12% effect (it minimized the size). The optimum values of process parameters that lead to minimum size of the particles were : CuSO4.5H2O concentration = 5.5 g/l, Current density = 37.5 mA/cm2, Ultrasonic amplitude = 35%, H2SO4 concentration = 0.1 ml/l.The SEM photographs were used to examine the morphology of particles. The results show that the shape and morphology widely vary between many modes : from treelike through irregular, angular, or rounded shapes to a wellfaceted truncated octahedron. The forming of well - faceted truncated octahedron copper particles is related strongly to the presence of ultrasonic vibration which plays the role of inhibitor.Energy dispersive spectroscopy (EDS) elemental analysis of copper nanoparticles indicates the high purity of most of samples except the cases where there are traces of oxygen from very thin layer of oxides and/or carbon from residual alcohol.The x - ray diffraction studies reveal that the resulting particles are a crystalline copper element with a face center cubic (FCC) crystal structure.

تطبيق نظام دعم القرار لانشطة الصيانة في مصفى الدورة Application of A Decision Support System For Maintenance Activities In Al - Daura Oil Refinery

اسم المؤلف: مصطفى محمد علي منصور
اسم المشرف: لمياء محمد داود لمى عدنان حميد
السنة: 2014
الموضوع الدقيق: الهندسة الصناعية
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: في ھذا البحث تم دراسة انشطة الصيانة في معمل دھون 3 احد معامل الدھون في مصفى الدورة حيث تم اختيار ھذا المعمل كونھ الاحدث والاكثر انتاجية مقارنة مع المعملين الاخرين وتم اخذ بيانات انشطة الصيانة لمدة عشر اشھر متتاليھ من ايار 2012 ولغاية شباط 2013 علما ان وح | In this research maintenance activities in lube oil factory (3) of Daura refineries is investigated for ten consecutive months from May (2012) to February (2013).This factory is the newest and largest in its capacity compared with lube oil factory (1 and 2). Dewaxing unit produces the greater products compared with other production units in lube oil factory (3). The frequency of breakdowns and type of maintenance were identified, Pareto chart are used to analyze the collected data. Results indicated that %95 of breakdowns of different equipments (pumps, exchangers, compressors, docks, filters, furnaces and towers) are due to mechanical causes, the rest are related to electrical causes.Pareto chart highlights that the most frequent failure for both pumps and exchangers followed by compressors and other equipments of lube oil factory 3.Loss production cost due to maintenance activities was also conducted in this study so as to analyze different aspects of maintenance activities for lube oil factory (3).The total loss in production due to breakdown in the ten months of this study is (99 Billion ID). It is worth’s mentioning that pumps registered the highest losses of production cost due to bad maintenance. Accordingly, decision making for maintenance activities is a multiattribute and decision support system is crucial to signify priorities and definealternatives. ERGO (Latin word meaning "therefore" or Greek word meaning "work", used as a prefix ergo - , for example, in ergonomics and it is generalpurpose decision support system using 35 criterion to choose the best alternatives) is employed so as to evaluate detailed scope and the best of best alternatives. ERGO results indicated that Pumps are the best alternative offered to decision maker to conduct the necessary maintenance ERGO identifies the equipment with the most frequent breakdown indewaxing unit, which causes the greater loss in production cost. Compressors were identified as the highest frequency failure equipment(s). Combining two criteria (frequency of failure and lost production cost) reveals that pumps are the best alternative.

تقليل ضياعات القص في مشكلة قطع الخامات احادية البعد باستخدام نموذج برنامج جاهز Trim Loss Minimization In One - Dimensional Cutting Stock Problem Using A Ready Software Model

اسم المؤلف: سلام قدوري داود
اسم المشرف: سوسن صبيح الزبيدي
السنة: 2014
الموضوع الدقيق: الهندسة الصناعية
الدرجة: ماجستير
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: تعتبر مشكلة قص الخامات واحدة من المشاكـل العملية المهمـة، لذا ركز البحث على دراسة مشكلة قص الخامات احادية البعد بالتفصيل، حيث تم دراسة تصنيف وخصائص وطرق حل هذا النوع من المشاكل بالاضافـة الى اقتراح اسلـوب حـل مناسب لتقليل ضياعات القص الحاصلـة في بيئـة ا | Cutting stock problem is one of the important operation problems. The one dimensional cutting stock problem is considered as obvious problem which should be centered to be solved, so this thesis focuses on studying classification, characteristics and solution methods for this problem, in addition to suggest suitable approach for minimization of the trim losses in actual environment, as it is required to fulfill all of the small required items with different lengths and quantities by cutting the identical large objects which are available as stock. The variety of lengths and quantities of these small required items makes the problem obvious in complexity to fulfill all items with minimization of Integer Linear Programing (ILP) which is aided by Advanced Interactive Multidimensional Modeling System (AIMMS) software used to solve research problems. This software used because that getting of accurate details and speed results for waste amounts, number of used stocks, total and efficient cutting patterns that are generated to getoptimal solutions.Our study has been applied in an actual environment (housing project with 41 building units in Azezeiyah - Wasset) being carried out by Al - Mansour Company of Iraq Ministry of Construction and Housing, where the reinforcement steel (Rebar) with standard length is considered as a backbone component of building structure.These problems have been studied according to different rebar diameter (25 mm, 16 mm, 12 mm, and 10 mm), where each problem is subdivided and solved according to basic building activity designs (foundation, columns, beams, slabs, stairs, balcony, and front arch building entrance), trim losses which were resulting from certain activity design - diameter problem that have lengths longer than required item lengths in the next activity designs are stored and utilized to get optimal stock ratios. The utilization stock ratio which is resulting of suggested solution approach (ILP) for all these one dimensional cutting stock problems has reached (98.53%), while the utilization of used stock in that actual environment got by Al - Mansour Company is lower than this percentage.
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