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نظام مراقبة قليل القدرة يعتمد على شبكات المتحسسات اللاسلكية Low Power Monitoring System Based on Wireless Sensor Network

اسم المؤلف: قصي شهاب حمد
الجامعة: الجامعة التكنولوجية - قسم هندسة الحاسوب
اسم المشرف: صالح مهدي القرعاوي مؤيد صادق كروك
الموضوع العام: هندسة الحاسبات
الموضوع الدقيق: هندسة الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2014
مكان الجامعة: بغداد
المستخلص: تعتبر انظمة المراقبة وكشف التطفل شرط مهم لامن الشركات والمؤسسات وحتى بالنسبة للمستخدم العادي. اعتمدت الانواع السابقة من انظمة المراقبة على البشر لادارة عملية المراقبة يدويا. استخدمت تكنولوجيا المتحسسات اللاسلكية في الوقت الحاضر في انظمة المراقبة على مدى و| Monitoring and intruder detection systems have been considered as the most important security condition for companies, institutions and even for the individual users. The old versions of the above systems depend on humans to manage the monitoring manually
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محاكاة التعريف غير المحدد والسيطرة لروبوت سكارا باستخدام الشبكات العصبية المعدلة Simulation of Non - Parametric Identification And Control of Scara Robot Using Modified Neural Networks

اسم المؤلف: دنيا عبد الكريم عبد القادر
الجامعة: جامعة بغداد
اسم المشرف: قيس سعيد الصباغ نادية عدنان شلتاغ
الموضوع العام: هندسة الحاسبات
الموضوع الدقيق: هندسة الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2011
مكان الجامعة: بغداد
المستخلص: The control of Multi - Input - Multi - Output (MIMO) plant is difficult problem when the plant is nonlinear and there are dynamic interactions between the plant variables. A good example of such a plant is an articulated robot with two or more joints.Con
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تطبيق متوازي لخوارزمية باستخدام RSA المعالجات المتعددة النواة ووحدة معالجة الرسومات A Multithreading Implementation of RSA Algorithm on Multicores And GPUS

اسم المؤلف: هبة محمد فاضل
الجامعة: جامعة بغداد
اسم المشرف: محمد عصام يونس
الموضوع العام: هندسة السيطرة والنظم
الموضوع الدقيق: هندسة السيطرة والنظم
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2014
مكان الجامعة: بغداد
المستخلص: تعرف خوارزميات المفتاح العام بانها ابطا من نظيرتها المفتاح الخاص في مجال خوارزميات التشفير وذلك بسبب ان الحسابات الرياضية عنصر اساسي فيها. تعد خوارزمية من خوارزميات المفتاح العام الاكثر شيوعا واستخداما. بناءا على ذلك، يعد تحسين سرعة (RSA) موضوع بحث غاية ف | Public key algorithms are known to be slower than private key alternatives in the area of cryptographic algorithms due to their basis in modular arithmetic. The most public key algorithm widely used is the RSA. Therefore, how to enhance the speed of RSA a
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تصميم وتنفيذ نظام مراقبة FECG عن بعد بالاعتماد على موقع الكتروني Design And Implemetation of Remote Web - Based Fetal Electrocardiogram (fecg) Monitoring System

اسم المؤلف: نور عبد الخالق زغير القريشي
الجامعة: الجامعة التكنولوجية - قسم هندسة الحاسوب
اسم المشرف: صالح مهدي القرعاوي مؤيد صادق كروك
الموضوع العام: هندسة الحاسبات
الموضوع الدقيق: هندسة الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2014
مكان الجامعة: بغداد
المستخلص: Recently, healthcare monitoring systems have utilized the modern wireless networks and internet technologies. One of the most developed applications in the healthcare monitoring systems is the fetal heartbeat detection. Obtaining fetal heartbeat has becom
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مصادقة المستخدم بالاعتماد على الميزات الديناميكية لضربات المفاتيح باستخدام الشبكة العصبية وطريقة تحليل المكونات الرئيسية User Authentication Based on Keystroke Dynamics Features Using NN And PCA

اسم المؤلف: مينا خضر عبيد
الجامعة: الجامعة التكنولوجية - قسم هندسة الحاسوب
اسم المشرف: شيماء حميد شاكر رياض جبار سوداني
الموضوع العام: هندسة الحاسبات
الموضوع الدقيق: هندسة الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2014
مكان الجامعة: بغداد
المستخلص: تعتبر ديناميات ضربة المفتاح خيارا جيدا للمصادقة على المستخدم بدلا من المصادقة المعتمدة على كلمة المرور التقليدية؛ كلمات السر هي عرضة لهجمات كلمة المرور. ديناميات المفاتيح تعتمد على ميزات التوقيت التي تستخرج عندما يقوم المستخدم بالكتابة باستخدام لوحة المفا | As a behavioral biometrics, Keystroke dynamics are considered a good choice for user authentication rather than the traditional password - based authentication; passwords are vulnerable to password attacks. Keystroke dynamics depend on the timing features
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طريقة محدثة لعملية تمييز الصوت A Modified Approach For The Sound Recognition Process

اسم المؤلف: مروة فاضل جاسم
الجامعة: الجامعة التكنولوجية - قسم هندسة الحاسوب
اسم المشرف: ازاد رحيم كريم
الموضوع العام: هندسة الحاسبات
الموضوع الدقيق: هندسة الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2014
مكان الجامعة: بغداد
المستخلص: The issue of discrimination of the sounds is one of the very important issues and has many applications in the field of identifying the sources of the sounds. So there are a lot of researches nowadays that serve this subject and are all looking for the be
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تمييز الغير مباشر للحروف اليدوية بواسطة الشبكات العصبية اعتمادا على عدة خوارزميات لاستخلاص الخصائص Offline Hand Written Letter Recognition Using Neural Networks Based on Multiple Feature Extraction Algorithms

اسم المؤلف: مريم خلف كاظم
الجامعة: الجامعة التكنولوجية - قسم هندسة الحاسوب
اسم المشرف: باسم عبد الباقي جمعة اياد غازي ناصر
الموضوع العام: هندسة الحاسبات
الموضوع الدقيق: هندسة الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2014
مكان الجامعة: بغداد
المستخلص: ھو احد حقول البحث في تمييز الانماط والذكاء الاصطناعي. نظام (LR) تمييز الحروف يمكنك من تحويل كتاب او مقالة في مجلة الى ملف في الحاسوب كنسخة الالكترونية، ومن ثم LR تحرير الملف باستخدام محرر نص مثل معالج النصوص. الاسلوب الاكثر شيوع التعليم الشبكة وھذه الخوا | Letter recognition (LR) is a field of research in pattern recognition, artificial intelligence and machine vision. A LR system is used to transform a scanned book or magazine article into an editable text form. In this work, letter recognition using Arti
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تصميم وتنفيذ خوارزمية توجيه ذكية لشبكات الحزم ذات النطاق الواسع Design And Implementation An Intelligent Routing Algorithm For Large Scale Packet Networks

اسم المؤلف: احمد ناهض حمزة
الجامعة: الجامعة التكنولوجية - قسم هندسة الحاسوب
اسم المشرف: منى محمد جواد محمود زكي عبد الله
الموضوع العام: هندسة الحاسبات
الموضوع الدقيق: هندسة الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2014
مكان الجامعة: بغداد
المستخلص: Routing algorithms are the key elements in determining the network performance. Therefore, in this thesis a model of logical topologies in the software has been proposed to examine the performance of the logical topologies and their routing algorithms for
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تخمين وازالة الضوضاء من الصور الملونة بالاعتماد على المنطق المضبب والتمثيل البياني Color Image Noise Estimation And Removing Based on Fuzzy Logic And Histogram

اسم المؤلف: عادل جلال يوسف
الجامعة: الجامعة التكنولوجية - قسم هندسة الحاسوب
اسم المشرف: منى محمد جواد اقبال حسين علي
الموضوع العام: هندسة الحاسبات
الموضوع الدقيق: هندسة الحاسبات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2014
مكان الجامعة: بغداد
المستخلص: تكون الصورة المراقبة في العديد من تطبيقات معالجة الصور الرقمية, ملوثة بسبب الضوضاء الذي يحدث اثناء اكتساب او ارسال الصور. حيث ان الضوضاء يقلل من جودة الصور ويؤدي الى نتائج غير مرغوب بها في المراحل المتعاقبة من معالجة الصور (مثل التقطيع, تميز الشكل, التحسي | In many of digital image processing applications, observed image is often corrupted by noise which may arise during image acquisition or image transmission. Noise reduces image quality and leads to unwanted results of subsequent stages of the image proces
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تصميم تقسيم مساحة نظام الارسال الضوئي لنظم الاتصالات Design And Implementation Of Optical Space Division Multiplexer For Tera (B/S) Communication Systems

اسم المؤلف: مصدق ماهر عبد الزهرة
الجامعة: جامعة بابل - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: ابراهيم عبد الله حمزة الشمري
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2017
مكان الجامعة: بابل
المستخلص: اتصالات الالياف البصرية هي العمود الفقري للبنية التحتية للاتصالات السلكية واللاسلكية التي تدعم شبكة الانترنت. النظام الاحادي الالياف المستخدم لنقل البينات لم يعد يلبي طلب الحصول على القدرة العالية والمتنامية بشكل مستمر. هناك العديد من الطرق الممكنة لزياد | Optical fiber communication system is considered as the backbone for the infrastructure of telecommunications that handles the internet. The exponentially growing capacity is no longer satisfied by using transmission of single mode fiber. There are several possible methods for increasing transmission capacity over fixed bandwidth. These include mix many signals with optical - carrier onto a one optical fiber by achieving various wavelengths, modulation employing different amplitude levels, and two orthogonal subcarriers and polarization. An extra dimension that a fiber can offer for achieving more information is space.This project demonstrates simulation systems for Space Division Multiplexing (SDM) transmission system using Few - Mode Fiber (FMF). Polarization division multiplexing (PDM) and Dense Wavelength Division Multiplexing (DWDM) techniques are also used in this system to increase total system data rate. For the ultra - high capacity need of SDM, Few Mode Fiber (FMF) was proposed as SDM best technology for obtaining ultra - high bit rate systems with long haul transmission. Inter - mode losses that appears in higher - order - modes was the most problem to be resolved. In this thesis, the description and design of three SDM systems were explored by using both QPSK and 16QAM modulation formats : single channel SDM system with PDM technique, 8 - DWDM channels over 7 modes SDM/PDM system, and 16 - DWDM channels over 10 modes SDM/PDM system proposed as future of ultra - high capacity optical system.By using 16QAM format and bit rate per channel of 40Gb/s, the maximum long reach of our designed single channel SDM/PDM system is 1020Km. A transmission reach of 760Km was achieved for 8 - WDM - 7modes - SDM/PDM system and 260 Km for 16DWDM - 10modes - SDM/PDM. At QPSK modulation format the maximum demonstrated reach was 1460 Km for single channel SDM/PDM system. A long - haul transmission of 1080 Km was recorded for 8 - WDM channels - 7modes - SDM/PDM system and 510 Km for 16 - DWDM channels - 10modes - SDM/PDM system.The total bit rate of single channel - 3modes SDM/PDM system was 240G/s at 40Gb/s bit rate per channel. The total bit rate was achieved by using 8 - DWDM channels - 7modes SDM/PDM system is 4.48 Tb/s at 40Gb/s. The highest bit rate was achieved by using 16DWDMchannels - 10modes SDM/PDM system so that the total achieved bit rate is nearly 12.8Tb/s.Chromatic Dispersion (CD) compensator using Digital Signal Processing (DSP) was proposed to compensate chromatic dispersion losses. Frequency and phase estimators were proposed in the designed systems to remove frequency offset and phase change by using Viterbi and Viterbi algorithms.Adaptive MIMO equalizer using constant modulus algorithms was proposed to compensate deferential group delay, polarization mode dispersion, and other losses simultaneously. Numerical results demonstrated that the methods are very effective in compensating the narrow band filtering and are very robust to channel estimation noise.The demonstrated systems were designed and tested by using (VPI transmission maker v.9.5) powerful software package.SDM techniques provided us with an important source to obtain more system flexibility, scalability, and capacity.
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تصميم مضاعف تناظري خطي محسن بنطاق واسع يعمل باربعة ارباع Design Of Improved Wideband Linear Four Quadrant Analog Multiplier

اسم المؤلف: رسل صلاح خضير
الجامعة: جامعة بابل - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: عبد الكريم مخيف عبيس
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2017
مكان الجامعة: بابل
المستخلص: استخدمت المضاعفات التناظرية على نطاق واسع في دوائر الاتصالات والشبكات العصبية ككاشفات للطور ومضاعفات للتردد ودوائر لمزج الاشارات والتضمين وفك التضمين. في التطبيقات التقليدية مثل دوائرالتضمين تعتبر ترددات التشغيل والسلوك الخطي للانظمة والمديات المسموح بها | Analog multipliers have been widely exploited in communication circuitries, phase detectors, neural networks, frequency multipliers, mixers, and modulation and demodulation circuits. In conventional applications, such as modulation circuits, the linearity, frequency of operation, and input voltage ranges are issues of great importance for multipliers. This work targeted these issues through the design of two types of four quadrant analog multipliers operating in wideband frequency ranges and having very high linearity with input and output voltage ranges of ±10V.The first wideband four - quadrant analog multiplier is designed using wideband squaring and operational amplifier (OPAMP) circuits. The wideband OPAMP is designed using 10 NMOS transistors based on 0.35 µm NMOS technology with supply voltages of ?12V. The wideband OPAMP has exhibited an open loop voltage gain of 3336545. The squaring circuit is built using two NMOS transistors and two wideband OPAMPs. The first wideband multiplier is built using two identical squaring circuits, two difference amplifiers, and one summing amplifier. It is characterized by high input - output linearity range of - 10 V to +10 V for both inputs, ±10 V input and output voltage ranges, and cutoff frequency of about 5 GHz. The second wideband four quadrant analog multiplier is designed using NPN bipolar junction transistors. It is built with two main circuits, which are the multiplier cell and the output circuit. The multiplier cell is built using a modified Gilbert multiplier, while the output circuit is a high gain circuit designed for changing the differential output of the multiplier cell to a single output having a voltage range of ±10 V. The multiplier circuit is designed with supply voltages of ?12 V. It is characterized by high input - output linearity range of - 10 V to +10 V for both inputs, ±10 V input and output voltage ranges, and cutoff frequency of about 1 GHz.Both multipliers are designed and tested on PSpice in ORCAD / Version 16.6.
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بناء معيد ترميز تكراري شبه مثالي للاشارات المرمزة المعتمدة على مخطط تانر Implementation Of Modified Suboptimal Iterative Decoding For Tanner - Graph Based Coded Signals

اسم المؤلف: محمد ثامر نصر
الجامعة: جامعة بابل - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: احمد عبد الكاظم حمد
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2016
مكان الجامعة: بابل
المستخلص: في هذا العمل, تم اقتراح خوارزميتين لتحسين اداء معيد الترميز التكراري التجميعي. الاول انجز باضافة رموز ارشاد بين سيل البيانات التي تدخل الى المرمز. في هذه الطريقة, رموزالارشاد ترمز مع البيانات المدخلة (رموز الارشاد المرمزه او الداخليه) مقارنة بالطريقة الاع | In this work, two algorithms were suggested in order to improve the performance of systematic RA decoding. The first one was accomplished by the insertion of pilot symbols between the data stream that entering the encoder. In this way the pilot symbols are encoded along with the input data (encoded or internal pilots) in contrast to the usual way where pilots are inserted after encoding (unencoded or external pilots). The positions where pilots should be inserted are chosen in such a way that to improve the minimum Hamming distance and/or to reduce the error coefficients of the code. Moreover, the known pilots have higher reliability than data and can significantly improve the initial decoding.The second proposed algorithm includes the utilization of the inserted pilots to estimate scaling (correction) factors. Two - dimensional (2D) correction system was suggested in order to enhance the performance of traditional Minimum - Sum (MS) decoding of regular RA codes. By calculating the mean square difference (MSD) between the values of received pilots and the a - posteriori data of bit and check node related to them, which are created by the MS decoder, an adaptive method can be achieved for getting the correction factors.Since encoded pilots in systematic RA code are embedded in data, it is possible to puncture all or part of them to increase the code rate. The pilots still have their effect on increasing the minimum Hamming distance.Extensive simulation tests reveal that the suggested quasi - optimal algorithms supply error performance be able to compare as Sum - Product (SP) decoding whilst maintain less complexity. Practical experiments are carried out by utilizing the capability of data acquisition toolbox supported by MATLAB to provide a hardware interface with the computer sound card. Here, the sound card plays the role of ADC and DAC converter in the physical layer. A different graphical user interfaces (GUI) are designed for the transmitting and receiving terminals to facilitate the selection of different code options. Signals are transmitted over wireless channel using a 2.4 GHz band indoor audio tranceiver. According to the aquired results, the modified coding system outperforms the original one when it is tested over AWGN and fading channels. An improvement may be realized about 1.5 dB and 1.3 dB at BER=?10?^( - 5) for punctured and unpunctured systematic (50,35,3,7) code with adaptive scaling, with three encoded pilots over AWGN channel and about 3.4 dB and 3.3 dB at BER=?10?^( - 4) for punctured and unpunctured systematic (50,35,3,7) code with constant scaling, with two encoded pilots over fading channel.
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حساب توزيع الطاقة الممتصة في راس الانسان باستخدام نطاق الفرق الزمني المحدد لانظمة الاتصالات المتنقلة Computation Of Sar Distribution In Human Head For Cellurlar Mobile Communication Systems Using Fdtd

اسم المؤلف: هويدا كمال عبد الفتاح
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: عضيد حسن سلومي
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2016
مكان الجامعة: بغداد
المستخلص: Widespread wireless communications system in the last few years, leads people to ask many questions about the advantages and disadvantages of those systems, especially about electromagnetic waves pollution and their effect on human health.The mobile device is frequently used by the general public from adult to child, one of the main sources of electromagnetic waves and very close to the human head. Therefore the focus of this research on the impact of electromagnetic waves from mobile to human health by measuring the Specific Absorption Rate (SAR), at the human head and the hand through SEMCAD - X that uses the Finite Different Time Domain (FDTD). SAR computation uses (FDTD) in the way the limited space of time, to calculate the specific absorption rate. The results have been compared with standards averaged over any 1 g of tissue and averaged over any 10 g of tissue. It didn't exceed the applicable standard.This work evaluates specific absorption rate (SAR) at different ages of three people. Firstly, old man, who was estimated to head 100% size of header used in the program SEMCAD - X. Secondly Adult man was estimated his head by 85% size of header used in program, and finally the child who was estimated his head by 65% size of header used in the program SEMCAD - X, the design hand has been used with all cases.The design of the mobile phone software works in four different packages of frequencies; the packets are the center frequencies 900MHz 1800MHz, 2100MHz and 2400MHz, when increased frequency the SAR increased but in the some state and frequency decreasing.The Evaluation of SAR in the head and the hand of the user device and the generic phone, the highest value of SAR decreases with increasing distance between the generic phone and the user's head and reducing the proportion was 50% for the old man, 40% for adult man and 35% for child. It can be noted that the angle of the rotation of the various frequencies is not fixed, while the ratio approximately is 25% for each angle of rotation.Also, it can be noted that for fixed frequency, the input power is increased to a double and the SAR have been used increased almost to a double.The different positions show that the methods of holding generic phone have a significant impact on the value of SAR. Therefore, the value of SAR can be reduced into 90% when using the correct method.The evaluation of SAR in these cases shows their influence on children and it was much greater than the adult human or old human by parentage 40% old man and 35% adult man.
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تمييز الحروف العربية المعزولة المكتوبة بخط اليد باستخدام الشبكات العصبية Recognition Of Isolated Handwritten Arabic Letters Using Neural Networks

اسم المؤلف: نهلة ظاهر حبيب بهية
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: منذر نعمان التكريتي
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الكهرباء
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2004
مكان الجامعة: بغداد
المستخلص: يتناول هذا البحث مشكلة تمييز الحروف العربية المعزولة المكتوبة بخط اليد باستخدام الشبكات العصبية. ان نظام تمييز الحروف العربية المقترح يتكون من ثلاث مراحل وهي : مرحلة مسح صور الحروف العربية ثم مرحلة معالجة الصور واخيرا مرحلة التدريب والتصنيف.ان المرحلة الاخ | This thesis presents an algorithm for recognition of an off - line isolated handwritten Arabic letters using neural networks.The handwritten recognition system present in this work consists of three modules : - 1 - Arabic letter scanning module 2 - Arabic letter preprocessing module 3 - Learning and recognition module.The proposed neural network in the third module is trained in two stages : The first stage employs Self - Organizing Map learning algorithm for clustering the input pattern, which are based on a database of 196 letters collected from 7 independent persons.In the second stage each of the similar output cluster is considered as a subnet introduced to neural network trained by Back - propagation learning algorithm for classification. Several networks architecture are designed in the second stage using 1 - hidden and 2 - hidden layers with 5 and 28 output nodes in the output layer with different number of hidden nodes and learning rate.To examine the efficiency of the system a database of 196 letters collected from other 7 independent persons are used, (in order to test the ability of the trained network to generalize). The results show that clustering the input pattern, using 1 - hidden layer and 28 nodes in output layer improve the network performance. The system was implemented using (IBM - PC) of type Pentium 3.The programming language used to design the system was c++ version 5.02.
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استراتيجية السيطرة على المقوم ثلاثي الاطوار المضمن بعرض النبضة (PWM) نوع رافع للجهد ولمصدر تغذية متغير الحالات

اسم المؤلف: منتظر كاظم عبد الله
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: تركي كحيوش حسن
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الكهرباء
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2014
مكان الجامعة: بغداد
المستخلص: In this thesis, a proposed control strategy is presented to improve the performance of the PWM boost type rectifier when operating under different supply voltage conditions (balanced, unbalanced, and distorted three - phase supply voltages). The proposed control strategy is classified into two parts, the first part is voltage controller and the second part is current controller. In the voltage controller, Repetitive Controller (RC) is used to reduce the even order harmonics in the regulated output dc voltage (5.62V (P.P.)) so small output capacitor (480µF) is used instead of large capacitor (920µF) that is used with the conventional controller (PI controller connected in series with a LPF). RC also reduces the even order harmonics (0.014A (P.P)) which appears in the reflected dc current (IMAX), this leads to reduce the odd order harmonics (0.01A) which appears in the input currents. While in the current controller, enhanced Phase Locked Loop (EPLL) technique is used to obtain sinusoidal and balanced three phases, to construct the reference currents, which are in phase with the fundamental supply voltages Therefore, the supply - side power factor is kept close to unity (0.9036 for extremely distorting case). As a result the calculations of the reference currents in the proposed control strategy does not require Clarke or Park transformations, the same for the calculations of the positive or negative sequence components. A proportional controller is used to give excellent tracking between the line and the reference currents. Using this approach makes the control strategy easy to understand and also it saves calculation time of the control algorithms if implements in real time. The complete system with the proposed control strategy is simulated using Matlab/Simulink (Version 2012). The obtained results for the complete system using repetitive voltage controller are compared to the results of the system with using the conventional voltage controller. The results with the repetitive controller show better responses and stable operation in the steady state under different input voltage conditions, as well as in the transient response under different disturbances.
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مبدل فوتوفولطائي مايكروي احادي المرحلة نوع فلايباك المغذي للشبكة Single Stage Grid - Connected Flyback Photovoltaic Microinverter

اسم المؤلف: مصطفى عباس فضل
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: تركي كحیوش حسن
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الكهرباء - قدرة ومكائن
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2016
مكان الجامعة: بغداد
المستخلص: Solar energy systems based on photovoltaic (PV) cells have attracted considerable interest in recent years due to their abilities of clear and seemingly limitless generated energy. Solar energy systems based on microinverter architectures are earning in publicity as they are less prone to shading and PV cell malfunction since each PV panel in the system has its own low power inverter.In this thesis two alternative modes of operation for the current source flyback microinverter are suggested : the discontinuous conduction mode (DCM), where a constant switching frequency (CSF) control method is applied, and the boundary conduction mode (BCM) between continuous conduction mode (CCM) and DCM, where a variable switching frequency (VSF) control method is used. These two control methods are analytically studied and compared in order to establish their advantages as well as their suitability for the development of an inverter for grid - connected PV applications.An optimum design methodology is developed, aiming for an inverter with the smallest possible volume for the maximum power transfer to the public grid and wide PV energy exploitation. The main advantages of the current source flyback microinverter are very high power density and high efficiency due to its simple structure, as well as high power factorregulation. The design and control methodology are validated by Powersimulation software (PSIM) and a laboratory hardware prototype is buildusing analogue and digital devices.The microcontroller type (PIC - 18F45K22) is used to implement perturb and observe (P&O) maximum power point tracking (MPPT) algorithm, and C language is used for programing the microcontroller. The simulation and experimental results are obtained to verify the proposed flyback microinverter.
الصفحات الاولى:

تحقيق دائرة المعدل الثابت للانذار الكاذب باستعمال منظومة البوابات المنطقية المبرمجة موقعيا Modified GO - CFAR Implementaion Using FPGA

اسم المؤلف: مصطفى صبحي كمال
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: رفعت طالب حسين حكمت نجم عبد الله
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الكهرباء
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2006
مكان الجامعة: بغداد
المستخلص: هذه الاطروحة تتعلق بتحليل ومعالجة تاثير الضوضاء المحيطية (Clutter) لمنظومة الرادار النبضي، يتطلب رادار الكشف الالي للهدف استعمال عتبة الية (Adaptive threshold) لتحقيق معدل ثابت للانذار الكاذب وذلك لغرض السيطرة على الانذار الكاذب الذي تسببه تغيرات في الضوض | This thesis deals with the analysis and processing of clutter for pulsed radar system. Automatic target detection radar requires adaptive thresholding achieved by Constant False Alarm Rate (CFAR) circuit in order to control the false alarm caused by variations in clutter background.This work focus on worst radar environment that happens when abrupt variation in clutter background merged with multi - interfering target, to detect target in such environments it need robust CFAR algorithm that excise the target spikes and clutter edges from CFAR window in order to give best possible estimation to the noise background. two important algorithms studied which are CA - CFAR and OS - CFAR algorithms in additional to the modified CA - CFAR algorithm. All these algorithms were simulated with mat lab v6.1 and applied them to three different clutter models that represent different environment cases the CA - CFAR family failed to handle model two and three also OS - CFAR family except OSGO - CFAR that handle all models successfully. For modified CA - CFAR family only modified GO - CFAR handle all models successfully and comparing with OSGO - CFAR the modified GO - CFAR need less hardware and processing time because it did not need sorting process that is essential for OSGO - CFAR. Therefore, the modified GO - CFAR is chosen to implement by using FPGA and another important feature in modified GO - CFAR algorithm that is parallel processing since the spike selection process is done at the same time with summing of samples process that make this algorithm much less in processing time from any other algorithm that work in the same environment. The FPGA chip that used to implement modified GO - CFAR algorithm need only three signals from the radar receiver to mach with the receiver circuit correctly which are time base clock signal period reset trigger signal and the pulse duration time. Therefore, the FPGA chip can work effectively with almost any radar receiver system
الصفحات الاولى:

مسيطر السرعة المثالي بالاعتماد على المتجه المسيطر لمسوق محرك التيار المستمر عديم الفرش Optimal Speed Controller Based On Vector Controlled For A Brushless DC Motor Drive

اسم المؤلف: مصطفى بشار عبد الملك
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: تركي كحيوش حسن
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الكهرباء - قدرة ومكائن
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2016
مكان الجامعة: بغداد
المستخلص: اصبحت محركات التيار المستمر عديمة الفرش شائعة جدا في الكثير من المجالات مثل في الصناعة والتطبيقات المنزلية؛ وذلك يعود الى مميزاتها العديدة على محركات التيار المستمر ذوات الفرش والمحركات الحثية؛ مثل كفائتها العالية, كثافة قدرتها العالية وحجمها الصغيرنسب | Brushless DC (BLDC) motors have become very popular in various fields such as in industry or home appliances; and that is due to their many advantages over the brushed DC motors and the induction motors such as their higher efficiency, high power density and respectively low volume. The traditional and most popular way to drive BLDC motor is by using six - step or trapezoidal technique. This technique however has several problems such as high torque ripple and high distortion in the currents. This thesis presents a BLDC motor drive system where the performance of the motor is improved on various aspects. The first aspect is to improve the speed response by using particle swarm optimization (PSO) technique to find the optimal parameters of the speed controller. The second aspect is to reduce the torque ripple associated with the traditional driving technique and also improve the dynamic response of the motor by using vector or field - oriented control to drive the motor. The third aspect is improving the total harmonic distortion (THD) of the voltages and currents by using multilevel inverter. The last aspect is driving the motor in sensorless operation for reduced cost and for applications where speed and position sensors cannot be used; this operation uses a flux - linkage observer with a phase - locked loop (PLL) structure to estimate the position and speed of the rotor. The control methods are modeled using MATLAB/Simulink program and the results show that the proposed systems has significant improvement in performance as compared with the traditional technique in terms of speed response, torque ripple and THD of the voltages and currents
الصفحات الاولى:

التاثيرات الكهربائية والبصرية لتشويب اغشية اوكسيد الخارصين (ZnO) المكونة لمتحسس الاشعة فوق البنفسجية بالفضة Electrical And Optical Effects Of Ag Doped ZnO Thin Film Based MSM UV Photodetectors

اسم المؤلف: محمد وسام ناجي
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: منير عبود هاشم غصون محسن علي
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2015
مكان الجامعة: بغداد
المستخلص: يستخدم اوكسيد الخارصين (ZnO) لكشف الاشعة فوق البنفسجية وذلك لكبر فجوة الطاقة وكبر طاقة اثارة الربط لهذا الشبه موصل. اوكسيد الخارصين كذلك يمتلك سرعة اشباع عالية وفولتية انهيار عالية. في هذا العمل تم تصنيع متحسس اشعة فوق بنفسجية نوع (معدن - شبه موصل - معدن) با | Zinc Oxide (ZnO) has been commonly used for ultraviolet detection due to large band gap and excition binding energy. ZnO has high breakdown electrical field, also has a much larger saturation velocity. In this work three ultraviolet Metal Semiconductor Metal (MSM) photodetectors were fabricated, based on ZnO and Silver (Ag) doped Zinc Oxide (SZO) with (2% and 4 % doping ratios) thin films. The technique used to prepare the thin films was sol - gel and spin coating technique by using Si (100) p - type. Silver interdigitated (IDT) electrodes were deposited on the films by a vacuum coating deposition technique to form the three devices.The electrical properties for the fabricated photodetectors (PDs) were studied using Semiconductor Characterization System (SCS) at room temperature ( 27 C^o). The applied voltage was in the range of ( - 5 to 5) V.The SEM images showed a non - uniform distribution of the Ag dopants, these dopants formed clusters and these clusters increased as the amount of Ag dopants increased. The mobility, carrier concentration, and roughness for the SZO films increased when compared to undoped film. The optical bandgap and the transmittance are decreased when the doping ratio is increased. The saturation current (I - S) was decreased by a factor of 4, and 12 for the devices based on Ag doped ZnO (with 2% and 4 % doping ratios) thin films, respectively. The sensitivity was significantly increased with increasing the doping ratio. This enhancement attributed to the roughness of the Ag dopants (clusters). The detectivity was increased for the devices based on SZO films. The high detectivity with low saturation current made the devices based on SZO films suitable for optoelectronic applications and integrated circuits. From the experimental data and analysis, it was found that the PD with ZnO : Ag 4 % doping ratio has higher responsivity and gain of 0.523 A/W and 257 , respectively. This is confirmed by thin film and device characterization which makes this PD suitable for UV detection purposes.
الصفحات الاولى:

النمذجة التحليلة لاداء الثنائي الضوئي p - i - n Analytical Modeling Of A P - I - N Photodiode Performance

اسم المؤلف: محمد شهاب احمد
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: منیر عبود ھاشم
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2014
مكان الجامعة: بغداد
المستخلص: The analysis of a silicon p - i - n photodiode with a uniform doping concentration in each layer is presented. The theoretical treatment aims at investigating the device operation and performance to obtain optimum values of photodiode parameters when operates as a photodetector.Large bandwidth, good responsivity, device speed and quantum efficiency at wavelength of interest, combined with its low operating voltage and capability, make this diode promising for optoelectronic receiver circuits for use in optical communication systems and computer interconnections.High speed silicon p - i - n photodiode which operate at 700 nm wavelength is reported. By using a reverse bias voltage to control electric field, a high quantum efficiency of 80% is attained corresponding to bandwidth of 6.5 GHz at depletion width of 5.36 ?m and biasing voltage of 27.5 V. The minimum detectable incident light signal power is 3.9 ?W corresponding to signal to noise ratio of 6.5*104. The results show that, there is trade - off between quantum efficiency and bandwidth. Since the intrinsic layer of a p - i - n photodiode can be made with a lightly doping concentration, a p - ? - n photodiode is also treated mathematically with a software tool, and the results obtained are very close to those for a p - i - n photodiode. The results are achieved with the aid of MATLAB programming tool version 8.1.0.604 (R2013a).
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تصميم وتنفيذ معالج باستخدام TM - CFAR مصفوفة البوابات المبرمجة FPGA Design And Implementation Of TM - CFAR Processor Using Field Programmable Gate Array

اسم المؤلف: علي هادي عبد الواحد
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: وليد خالد عبد علي
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2006
مكان الجامعة: بغداد
المستخلص: This Thesis proposes on a project whose aim is to implement architectures for CFAR processor employed in radars. These proposed architectures are implemented by using Field Programmable Gate Array (FPGA) technique, with observance of feature desired as flexibility and speed without performance loss. This design written in VHDL Hardware Description Language that can be used to accelerate the implementation. In this thesis, the proposed by design is implemented using MATLAB Simulink on the Trimmed - mean Constant False Alarm Rate Processor(TM CFAR) to obtain system parameters and to test the flow of signal through the system, and then used FPGA devices. FPGA architecture of TM - CFAR processor is implemented to overcome the large processing time required in case of multi - target environment. The use of this technology is suitable because it offers high flexibility in modifying and even developing the required design with a reduction in the required number of hardware and cost. In addition to the main features of the processing chain architectures such as degree of parallelism, small size, accuracy and high computational speed, there is a requirement for generality and adaptively i.e. the ability to handle many different models of operation in different environments. The FPGA implementation of the design is achieved using Xilinx Virtex - II platform as a suitable selected programmable device. The development of the system software for this work has been done using Active HDL 3.5, and ISE Navigator 6.3i programs.
الصفحات الاولى:

تمييز الاهداف الرادارية وذلك عن طريق استخدام الشبكات العصبية وافضلية الحشد الجزيئي Radar Target Recognition Using Neural Network And Particle Swarm Optimization

اسم المؤلف: علي ناظم غالب
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: وليد خالد عبد علي
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2014
مكان الجامعة: بغداد
المستخلص: In the last decades, the pattern recognition and classification are taking an important area of the research. One of the main applications of pattern recognition is the radar target recognition which is vital in radar system.In this this work, a radar signal were used and analyzed for three targets present a contribution is this trend (aircrafts SR - 71, C - 130 and AH - 64), and used as initial data, then variations are made to simulate the target signal variation (50 range profile for each target).A wavelet transform (multi resolution decomposition) is used to reduce the dimensions of radar range profile and then leads to reduce storage and computation.The wavelet transform including two procedures, the first one using approximation and details coefficients as feature extraction, while second procedure use related with the details coefficient only.Artificial Neural Network (ANN) is used as recognizer. The Feed Forward Neural Network (FFNN) and Elman Recurrent Neural Network (ERNN) are used. The network was trained using Supervised Learning Algorithms. The FFNN was trained by (Levenberg - Marquardt (lm), Bayesian regulation (br), particle swarm optimization). The (ERNN) was trained by (lm, br).The best recognition rate of three targets is obtained by using the feature extraction from (normalized details wavelet coefficient) and the ERNN trained by (br). The recognition rate in this procedure is about 96% compare with other methods.When adding the AWGN S/N=5db, the recognition rate reducing to 85%.
الصفحات الاولى:

تمييز الوجوه اعتمادا على التحويلات الكونتورية ومصنف الشبكة العصبية متعددة الطبقات Face Identification Based On Contourlet Transform And Multi - Layer Neural Network Classifier

اسم المؤلف: علي فتاح حسون
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: ماهر خضير محمود
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2016
مكان الجامعة: بغداد
المستخلص: Face recognition plays an important role in many applications like security, banking, access to buildings, and surveillance …. etc.Because of the face image can significantly change due to changing in some factors, such as lighting conditions, facial expression, and others factors, therefore face recognition is still a challenging mission. Useful properties of the Contourlet Transform (CT) are exploited in this thesis to investigate more discriminant features to enhance the face identification performance. In this thesis, a face identification system is suggested based on CT, and Multi - Layer Neural Network (MLNN) Classifier. The main reasons behind using the CT are : First, the CT supports progressive data compression/expansion, hence it is used for image compression. Second, the features in human face are not just horizontal or vertical. CT is utilized for feature extraction because it is a genuine 2D transform that can capture the edge information in all directions. After decomposing an image by CT, low and high frequency coefficients of CT are calculated in different scales and various angles. Most significant information of faces is contained in coefficients, which is important for face identification. The frequency coefficients are utilized as an input feature vector for a neural network classifier. Simple feed forward MLNN neural network is used to achieve the identification process. The network parameters are tuned to optimal values, in order to produce fair comparison between different types of feature vectors. To evaluate the algorithm performance, seven standard databases, and a proposed database are used. Some of them are of high variability, to examine the algorithm robustness against variability. In addition, the proposed algorithm is also evaluated using a generated database composed from five databases. Then the suggested method is compared with other classical feature - based methods such as, wavelet, Principle Component Analysis (PCA), and CT - PCA. The results indicate that the CT - based method has better identification (ID) rate, and is faster than the Wavelet - based and the PCA - based methods. This is due to the high sparsity of the CT and its efficient capability of compression. The ID rates obtained for a tested databases are Japanese Female Facial Expression (JAFFE) database (100%), face 94 database (99.34%), proposed database (98.55%), ORL database (96.5%), Senthil database (92%), Yale database (90%), FERET database (76.2 %), and FEI database (72.57 %), and comparing with other systems, an average identification rate 90.64% for the CT, 85.71% for the Wavelet, 53.92% for the CT - PCA, and 46.7% for the PCA for all tested databases.Moreover, the characteristics of low and high frequency sub bands a are studied with their effect on ID rates. The simulation results indicate that the best identification rates are obtained when using only the low frequency sub - band for all tested databases
الصفحات الاولى:

استخدام اغشية اوكسيد الخارصين (ZnO) الرقيقة في متحسس لتركيز الهيدروجين من نوع ترانزستور تاثير المجال ممدود البوابة Zinc Oxide Thin Films - Based Extended - Gate Field - Effect Transistor (EGFET) As Ph Sensor

اسم المؤلف: علي عزام عبد اللطيف
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: رعد حمدان ظاهر غصون محسن علي
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2015
مكان الجامعة: بغداد
المستخلص: ظهر في السنوات الاخيرة اهتمام ملحوظ في استخدام متحسسات تركيز الهيدروجين (الرقم الهيدروجيني) من نوع ترانزستور تاثير المجال (FET) في التطبيقات الطبية الحيوية مثل دم الانسان, اليوريا واللعاب لان عملية تصنيع متحسسات تركيز الهيدروجين تتجه نحو التكلفة المنخفضة | In recent years, there is noteworthy interest in using pH - sensors based on Field Effect Transistor (FET) in biomedical applications such as human blood, urine, and saliva because the fabrication of pH - sensors is tending toward low cost, small size, disposable, and real - time measurement. In this work, Extended Gate Field - Effect Transistor (EGFET) pHsensors were built using thin films of Zinc Oxide (ZnO) doped with Palladium (Pd) as sensing membranes. The Pd - doped ZnO thin films with different molar concentrations (Pd = 0%, 2% and 4%) were deposited onto p - type Si(111) substrate by sol - gel method. The surface morphology of the prepared films was imaged and studied by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). The crystal structure of the fabricated films was examined by X - Ray Diffraction (XRD) test. The optical and electrical characteristics of the films were measured using spectrophotometer and Hall - Effect measurement device, respectively.The EGFET pH - sensor has been prepared by linking the fabricated sensing devices to the gate terminal of a commercial Metal - Oxide - Semiconductor Field - Effect Transistor (MOSFET CD4007UB).The fabricated sensing devices were immersed in buffer solutions with pH range of (pH 3 ? pH 11). The pH sensing characteristics of ZnO and Pd - ZnO/silicon EGFET devices were studied using Semiconductor Characterization System (SCS - Keithley 4200).The ZnO EGFET sensor exhibits voltage sensitivity and linearity of 31.5 mV/pH and 0.9809 (or 98.1%) in linear regime with pH range of (pH 3 - pH 11). The voltage sensitivity and linearity of Pd - doped ZnO (with 4% molar concentration of Pd) EGFET device in the linear regime with pH range of (pH 5 - pH 11) are 27.86 mV/pH and 0.9785 (or 97.85%), respectively. The experimental results show that the Pd - doped sensing films by sol - gel method cannot be adopted for whole pH range. This means that the doped films have fewer amounts of H+ ions sensing sites at its surface than undoped ZnO fims.
الصفحات الاولى:

تحليل الاشارات المشفرة ثنائيا باستخدام الترشيح الموائم وغير الموائم لتقليل الفصوص الجانبية Analysis Of Binary - Coded Signals Using Matched And Mismatched Filtering For Sidelobe Reduction

اسم المؤلف: صلاح حسن عباس
الجامعة: الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اسم المشرف: اسماعيل محمد جابر
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
الموضوع الدقيق: هندسة الكهرباء
الدرجة: ماجستير
اللغة: الانكليزية
السنة: 2009
مكان الجامعة: بغداد
المستخلص: Various types of binary phase - coded signals are studied in terms of their correlation properties. Then, matched filtering technique as well as mismatched filtering techniques is applied to the codes studied previously in order to reduce the sidelobes of the compressed binary phase - coded signal around the mainlobe, and consequently increase the detection of the received signal. Each filtering technique is performed using programs written by the programming language of MATLAB version 7.4.0.287 (R2007a). White Gaussian noise is introduced in the assessment made to both the filtering techniques and the codes that are adopted in this thesis.The MATLAB programs are tested on various types of binary phase codes that are adopted in this thesis to calculate the criteria to choose the best filtering technique. These criteria are peak sidelobe level, the integrated sidelobe level, and the signal - to - noise ratio loss. Later, the results, which are obtained according to these mentioned criteria, are used to test different filtering techniques on the chosen periodical and aperiodical binary phase codes to choose the best one.It is found that, the optimal peak sidelobe level (PSL) filtering technique is the best filtering technique for the aperiodical binary phase codes in terms of the peak sidelobe level, and in terms of an acceptable signal - to - noise ratio loss. The optimal integrated sidelobe level (ISL) filtering technique comes in the second place.While, it is found that, the mismatched filtering technique is the best filtering technique for the periodical binary phase codes in terms of an acceptable signal - to - noise ratio loss.
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