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تمييز الحروف العربية المعزولة المكتوبة بخط اليد باستخدام الشبكات العصبية == Recognition Of Isolated Handwritten Arabic Letters Using Neural Networks

Author name: نهلة ظاهر حبيب بهية
Supervisor name: منذر نعمان التكريتي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: 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.

استراتيجية السيطرة على المقوم ثلاثي الاطوار المضمن بعرض النبضة (PWM) نوع رافع للجهد ولمصدر تغذية متغير الحالات

Author name: منتظر كاظم عبد الله
Supervisor name: تركي كحيوش حسن
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: مصطفى صبحي كمال
Supervisor name: رفعت طالب حسين | حكمت نجم عبد الله
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: 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

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

Author name: صلاح حسن عباس
Supervisor name: اسماعيل محمد جابر
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: 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.

نظام الاخفاء الصوري المعتمد على تحويل المويجة والاشارات الفوضوية

Author name: سرى فهمي يوسف
Supervisor name: حكمت نجم عبد الله
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تطبيق الشبكة العصبية في تكوين الشعاع المتكيف لنظام الهوائي الذكي == Neural Network Application In Adaptive Beamforming For Smart Antenna System

Author name: سليمان احمد غازي
Supervisor name: عضيد حسن سلومي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: انظمة الهوائيات الذكية تعمل على تحسين الاداء وزيادة في السعة لانظمة الاتصالات المتنقلة. ويمكن لانظمة الهوائيات الذكية حل مشكلة نظام الاتصالات المتنقلة مثل التدخل في نفس القناة، والتاخير الحاصل نتيجة الانتشار والمسارات المتعددة التي تاخذها الاشارة عن طريق | The smart antenna systems are promise to provide performance improvement and capacity increasing for the base station of mobile communication systems. Smart antenna systems can solve the problem of mobile communication system such as co - channel interference , delay spread and multipath by an advance signal processing technology called beamforming. In this work artificial neural networks (Feed Forward Neural Network (FFNN) and feedback Elman Recurrent Neural Network (ERNN) ) are used for smart antenna adaptive beamforming for one and multiple targets.Neural network is used to calculate the optimum weights of antenna array to adapt the radiation pattern of the antenna array by directing multiple narrow beams toward the desired users and nulling interference or unwanted users. FFNN and ERNN are trained by supervised backpropagation learning algorithms, FFNN was trained by using Levenberg - Marquardt (lm),Resilient Back - Propagation (Rprop), Gradient descent with momentum and adaptive learning rate (gdx), Gradient descent and adaptive learning rate (gda) and biasing regulation(br), while lm and Rprop are used to train ERNN..The simulation results show that the best performance of smart antenna adaptive beamforming for one and multiple targets is obtained when the NN (FFNN and ERNN) trained by lm algorithm as compared with other algorithms, since it consider the fastest supervised training algorithm but with more memory requirement. Where the performance of FFNN training phase based (lm) algorithm for single target for five element uniform linear array antenna is [2.746641e - 14] at epoch 27 with best validation performance and best test performance approximately equal to the best training performance. While The performance of ERNN training phase based lm algorithm for single target is [1.121938e - 14] at epoch 38 with best validation performance equal to [1.682442e - 14] and the best test performance is [3.363946e - 14].The neural network model in adaptive beamforming are compared with smart antenna adaptive beamforming based on Least Mean Square (LMS) algorithm, and gave better performance than LMS.

ضغط الكلام باستخدام ترميز التنبؤ الخطي في مجال تحويل المويجة == Speech Compression Using Linear Prediction Coding In Wavelet Domain

Author name: مصعب تحسين صلاح الدين
Supervisor name: ماهر خضير محمود العزاوي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تصحيح الخطا لبيانات كلام مضغوطة بــ سيلب == Error Correction For Speech Compressed Data Using CELP

Author name: محمد حميد خضير الدركزلي
Supervisor name: خميس عواد زيدان
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تصميم ومحاكاة هوائي جزئي متعدد النطاق الترددي للاتصالات اللاسلكية == Design And Simulation Of Multiband Fractal Antenna For Wireless Communication

Author name: ماهر حسين حمد
Supervisor name: عصام محمود عبد الباقي | جواد كاظم علي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تحليل معالج نسبة الانذار الكاذب الثابت الابدالي المحسن (IS-CFAR) لمختلف حالات سوير لنك للاهداف الرادارية == Analysis Of Improved Switching Constant False Alarm Rate Processor (IS - CFAR) For Different Swerling Radar Target Cases

Author name: كريكور الكزاندر ارمايس
Supervisor name: وليد خالد عبد علي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

اداء تخمين القناة في نظام التقسيم الترددي المضاعف المتعامد المستند على ترتيب الحاملات الموجهة المقطعي عبر قناة الخفوت نوع رايلي == Performance Of Channel Estimation For (OFDM) System Based On Block - Type Pilot Arrangement In Rayleigh Fading Channel

Author name: فادية نوري حمادي النعيمي
Supervisor name: مها جورج زيا
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

خوارزمية اخفاء المعلومات الصورية معتمدة تحويل المويجة المتقطع والتشفير فائق الجودة == Image Steganographic Algorithm Based On DWT And Turbo Coding

Author name: عواطف علي جعفر
Supervisor name: رفعت طالب حسين | حكمت نجم عبد الله
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تقويم اداء المرشحات لمنظومة كشف الاهداف المتحركة باستخدام خوارزميات مختلفة لازالة الاشارات المتغيرة وغير متغيرة غير مرغوب فيها == Evaluation Of MTI Filters Cancellation Using Different MTI Algorithms Against Non - Stationary And Stationary Clutter

Author name: علي خالد جاسم
Supervisor name: وليد خالد عبد علي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

مشكلة نسبة قمة قدرة الاشارة الى معدلها في منظومة التردد المتعامد المتعدد التقسيمي وبعض حلولها == Peak To Average Power Ratio Problem And Some Solutions In Orthogonal Frequency Division Multiplexing System

Author name: علي جليل طاهر سباهي الظاهري
Supervisor name: ماهر خضير محمود العزاوي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

مقارنة نظام التقسيم الترددي المضاعف المتعامد مع نظام تضمين التردد الواحد بوجود تقنيتي المعادلة في مجال التردد والتضمين المتكيف == Orthogonal Frequency Division Multiplexing Versus Single Carrier Modulation With Frequency Domain Equalization And Adaptive Modulation

Author name: عباس سلمان حميد
Supervisor name: ماهر خضير محمود العزاوي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

منظومة تعريف المتكلم غير المعتمدة على النص == Text - Independent Speaker Identification System

Author name: طيف علي مهدي
Supervisor name: ماهر خضير محمود
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تصميم وبناء منظومة مزج تقسيمات التردد المتعامد المرتكزة على شفرة الالغاء متعددة الحدود و تحويل المويل باستخدام مصفوفة البوابات المبرمجة الواسعة == Design And Implementation Of Slantlet Based Polynomial Cancellation Coding - OFDM System Using FPGA

Author name: صفاء عبد الخالق علي
Supervisor name: حكمت نجم عبد الله
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

الرؤية المجسمة لتخمين المسافة باستخدام الكاميرات البصرية == Stereo Vision Distance Estimation With Optical Cameras

Author name: صبا علي صادق محمد
Supervisor name: محي محمد العزاوي | ظافر رافع زغير
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

شفرات تصحيح الخطا المختلفة الطول == Variable - Length Error - Correcting Codes

Author name: سهى قاسم هادي العبيدي
Supervisor name: ماهر خضير محمود العزاوي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

اداء نظام تقسيم الشفرات المتعدد المداخل ذي المتتابعة المباشرة باستخدام التسوية في مجال التردد عبر قناة الخفوت الترددية الاختيارية من نوع رايلي == Performance Of Direct Sequence - Code Division Multiple Access Using Frequency Domain Equalization In Frequency Selective Rayleigh Fading Channel

Author name: سمير اكرم داود الشمري
Supervisor name: مها جورج زيا
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

التعرف على الاشارات المضمنة رقميا باستخدام تحويل المويجة == Identification Of Digital Modulated Signals Using Wavelet Transform

Author name: حيدر عبد حسيـن تقـي
Supervisor name: ماهر خضير محمود العزاوي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

اخفاء بيانات الوسائط المتعددة بسعة عالية باستخدام النظام الفوضوي والتحويلات الكنتورية == High Capacity Steganography Based On Chaos And Contourlet Transform For Hiding Multimedia Data

Author name: زينب نجيب عبد الحميد
Supervisor name: ماهر خضير محمود
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تصميم وبناء راديو معرف برمجيا بمصوفة البوابات المبرمجة الواسعة باستخدام مشفر لغة الكيان المادي الكتلي == Design And Implementation Of FPGA Based Software Defined Radio Using Simulink HDL Coder

Author name: حسين علي هادي
Supervisor name: حكمت نجم عبد الله
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تحسين اداء نظام التقسيم الترددي المضاعف المتعامد المتعدد المداخل والمخارج باستخدام الشبكات العصبية الاصطناعية == Performance Enhancement Of MIMO - OFDM System Using Artificial Neural Networks

Author name: حراء رحيم حاتم
Supervisor name: اسماعيل محمد جابر | حنان عبد الرضا عكار
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تشفير الكلام باستخدام نظام لورينز الفوضوي ذي الرتب الكسرية == Speech Scrambling Employing Lorenz Fractional Order Chaotic System

Author name: جعفر قاسم كاظم
Supervisor name: ماهر خضير محمود العزاوي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
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