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دراسة وتحليل الاظمحلال في قناة النظام الخلوي GSM == A study and analysis of fading in GSM mobile channel

Author name: علاء عدنان سليم
Supervisor name: عايد خلف السامرائي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:

تحسين التمييز للشبكات العصبية المنعدمة الاوزان == Recognition Enhancement of Weightless Neural Network

Author name: عمار علي مصطفى
Supervisor name: محمود حمزة المفرجي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electrical Engineering Branch
Language: English
University location: Baghdad
Key words:
  • Pattern Recognition
  • RAM - based Weightless Neural Network
First pages:
Abstract: الفعل الذكي للشبكات المتعلمة في هذا البحث يركز على الشبكات المتعلمة في منظومة تمييز الانماط المعتمدة على الذاكرة. ان الفعل الذكي في هذه المنظومات يكمن في القابلية على تمييز الانماط التي لم تتدرب عليها مسبقا وذلك يتم بالاعتماد على ظاهرة التعميم. الهدف من ا | The intelligent action of the learning network in this research concentrates on the learning network in the pattern recognition systems that are based on the Random Access Memory. The intelligence action in the pattern recognition system is the capability to recognize other patterns that were not learned before in the system depending on the generalization. The objective of the research is oriented to improve the performance of the learning network in pattern recognition system. A pattern recognition system that based on Random Access Memories is developed and evaluated for classifying non - deterministic data with particular reference to unconstrained handwritten Arabic numerals and traffic signs patterns.Various techniques are presented which allow the system to be optimized, giving an increase in the performance and confidence of the results.The results obtained showed the improvements of n - tuple and VG - RAM WNN systems as learning network. Techniques used to enhance the performance are investigated. The averaging of the training patterns for colored images is the proposed system. This technique gives improvements to the system performance in term of required storage size and recognition speed.

تحسين الفولتية وتقليل خسائر منظومة الشبكة العراقية باستخدام افضل جهاز FACTs == Improvement of Voltage Profile And Reduce Iraqi Grid System Losses By Using Optimal FACTs Device

Author name: سيف اسعد عبد الحسين
Supervisor name: رشيد حميد الربيعي | انعام ابراهيم علي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electrical Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: الغرض من هذا العمل هو تحسين الجهد والتقليل من خسائرالقدرة للشبكة العراقية ( 400kV ) عن طريق تركيب اجهزة ( FACTs ) في مواقع مختلفة تحت حالة خطا ومقارنة النتائج مع تلك دون وجود (FACTs) تحت نفس الظروف.تم تحديد الموقع الامثل للـ(FACTs) على اساس الخوارزميات | The aim of this work is to improve the voltage profile and reduces power losses of Iraqi (400kV) power grid system by installing Flexible Alternating Current Transmission System devices (FACTs).The optimal location of the FACTs device was specified based on Genetic Algorithm (GA) optimization method and power system analysis toolbox ( PSAT) package, it was utilized to search for optimum FACT parameters setting and location based objective function that depends on the power and voltage as fitness.MATLAB (R2011a) was used for running both GA program and Power System Analysis Toolbox (PSAT) version 2.1.6, Newton Raphson method also used for solving the load flow of the system and the Trapezoidal method for the non - linear differential equations.Two systems have been implemented in this work as follows; • IEEE - machine 9 - bus system.• INSGS 11 - machine 24 - bus, 39(400kV) overhead transmission line.The GA program is implemented on IEEE 9 - bus system, then after getting the appropriate results the same procedure repeated for the Iraqi grid system which is more complicated, its used to find the optimal location of Unified Power Flow Controller (UPFC). The results obtained from GA have been compared with PSAT and showed that the installation of (UPFC) devices at the optimal locations of the Iraqi grid gives an improvement in the power losses and voltage after subjected to the three phase fault to ground at different locations and different cases (temporary fault, permanent fault).

تصميم مسيطر وتحليل مولد حثي ثنائي التغذية مع سرعة الرياح المتغيرة == Controller Design And Analysis of Doubly - Fed Induction Generator With Variable Speed Wind

Author name: سراج منهل حمید
Supervisor name: حسین ثاني رشك
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering - Power and Machinery
Degree: Master
University: University of Technology - Electrical Engineering Department - Electrical Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: The Wind Energy is one of renewable energy and has become very popular and more attractive, as a result of many factors, some of these factors are, rising oil prices, worldwide awareness of the decline in world oil production, an raise in the price of natural gas. Therefore the need for renewable energy has been very important.This work deals with Doubly Fed Induction Generator (DFIG) based wind turbine. By studying the performance of DFIG connected to the grid with constant and variable speed wind. Three cases are considered and implemented using Matlab/Simulink. The first case is studied the effect of the size of capacitance at DC - bus with constant wind speed using space vector pulse width modulation (SVPWM) switching frequency 10KHZ and two values of capacitance.The second case is studied the effect of three phase fault condition, at 33KV line.The third case is that when the input is variable speed wind, the simulation results illustrate that is with variable wind speed and conventional values of PI controllers gains the generator system behavior show increasing in rising time and maximum overshoot of generated power, the control circuit is needed for optimization to improve the generated power. This optimization can be made by tuning the controllers parameters with optimal values, so the optimization is made by using Particle Swarm Optimization (PSO). The new optimal controllers parameters(PI - PSO) make the system more efficient from the results by reducing the ripple of DC - Voltage and maximum overshoot. And the generated active power get more smooth and rising time has been reduced.

تصميم ترميز تحويل لوبي في القنوات الاسلكية == Design of Luby Transform Code Over Wireless Channel

Author name: نبيل احمد مصدق
Supervisor name: وائل عبد الحسن هادي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: ترميز التحويل لوبي) هو نوع من الترميز النافوري يعمل بدون اي معلومات عن القناة. في هذا العمل، تم تصميم LT code)) باستخدام ماتلاب، التصميم يتكون من ثلاثة اجزاء ( Encoder ,Decoder, channel ). في الجزء الخاص بتصميم الـ (Channel ) استخدمنا (( flat fading ch | Luby transform code (LT Code) is a type of fountain codes operating without any information about channel. In this work, LT code design of LT code implemented by using Mat lab as simulation software, our design consists of three parts (encoder, channel and decoder). In the channel design, flat fading channel will be used as a noisy channel to measure the performance of LT code over this type of channels. From the result obtained, SNR improvement by (30dB) at (BER=?10?^( - 4)) compared with data effect by the fading channel without coding with BPSK modulation model under different values of degree of distribution (d). Other type of modulation model (QPSK) used to measure the effect of changing the modulation type on the code performance. From the results obtained, SNR improvement by (31dB) at (BER=?10?^( - 4)) compared with data effect by the fading channel without coding. The degree of distribution (d) is a critical point of design, two types of distribution presented in this work, robust soliton distribution (RSD) and ideal soliton distribution (ISD). (ISD) works poorly in practice, (RSD) is a practical way used to get the degree of distribution in design by adding two extra parameters (c and ? ) which provide the spike element (k/R) in high degree distribution to ensure the continued of decoding process. As a result obtained the value of (c) has a major effect on the spike position on high degree (c=0.15,k/R=10 and c=0.2,k/R=7) with selective value of ?=0.5.The successful decoding probability for two types of degree distribution is very important, the value of successful decoding probability for (ISD) for low number of encoding packets (50 - 100) packet is greater than the value of successful decoding probability for (RSD). In the high number of encoding packets (>150) the value of successful decoding probability for (RSD) is greater than the value of successful decoding probability for (ISD).Encoding time for two type of distribution also discussed in this work, based on the results obtained the encoding packets time when using (RSD) is less than the encoding packets time when using (ISD).

تخمين حالة منظومة الشبكة العراقية استنادا الى تقنية امثلية الحشد الجزيئي == Iraqi Super Grid Network State Estimation Using Particle Swarm Optimization (PSO) Techniqu

Author name: انمار جاسم حميد
Supervisor name: افانين انور عبود
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering - Power and Machinery
Degree: Master
University: University of Technology - Electrical Engineering Department - Electrical Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: يعتبر تخمين حالة منظومات القدرة الكهربائية من الامور المهمة في تشغيل منظومات القدرة وخصوصا في حالة الحمل الزائد على شبكة الطاقة الكهربائية من خلال دوره في ضمان تشغيل اكثر اقتصاديا وامانا. تم في هذا العمل دراسة تخمين حالة منظومة القدرة واقتراح طريقة فعا | Due to the increasing stress on power system networks, state estimation recently became a main matter in the operation of power systems through its important role in ensuring the secure and economical operation of the power system. This work presents a study of a problem of power system state estimation, and proposes an efficient and reliable optimization approach to solve the power system state estimation problem. Two programs have been proposed and implemented in order to overcome the disadvantage of the classical optimization problem and search for the optimal solution of state estimation in power systems, the first program is a conventional state estimation program based on Weighted Least Square (WLS) method, and the second program is an intelligent program based on Particle Swarm Optimization (PSO) technique. All programs have been implemented using MATLAB and have been developed to solve the state estimation problem of the Iraqi Super Grid network (400kV). The proposed programs have been examined and tested on the 14 - bus IEEE and 30 - bus IEEE test standard system. The results were compared with those of the previous published papers. Then, the two programs were applied on the Iraqi Super Grid network (400 kV). The tests proved that the two methods are very efficient and suitable for on - line applications since they are concise and require few computations. The results show that the convergence of the (PSO) technique to the optimal solution is more accurate than (WLS) method. On the other hand, the PSO has an acceptable execution time compared with the freezing time of Iraqi Supervisory Control and Data Acquisition (SCADA) system approved by the Iraqi national grid.

تصميم وتنفيذ رادار تضمين التردد ذو الموجة المستمرة لنظام السرعة التكيفي للسيارات == Design And Implementation of Frequency Modulation Continuous Wave Radar For Adaptive Cruise Control of Car Applications

Author name: تمارا زهير فاضل
Supervisor name: منال حمادي جاسم
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: The traffic accidents became significantly obsession and concern for all members of society, and has become one of the most important problems that sap physical, human resources and human potential. The researches show that the damaged property and other costs may equal 3% of world’s gross domestic product, which have been required to work in finding solutions and suggestions and put them into practice to reduce these incidents.The insertion of preventive safety applications into the car system can avoid the above mistakes. In this work, a design and implementation of Frequency Modulation Continuous Wave (FMCW) radar system working at 77GHz for Adaptive Cruise Control (ACC) technology is proposed. Using MATLAB R 2013 which is a flexible system to estimate the speed and distance in accordance to vehicle ahead, which reduces the forces on the rate of accidents by warning the driver when two vehicle become too close.Also, the principle of FMCW radar is presented to generate Linear Frequency Modulated Continuous Wave (LFMCW) sweep waveform through frequency bands with triangular frequency modulation using Voltage Control Oscillator (VCO), a triangle sweep pattern adopt will resolve ambiguity without Doppler processing. which improves the decision making before hardware implementation.Proteus Professional v8 and Micro C PRO v 6.1 compiler is used for Peripheral Interface Controller (PIC) to design a proposed collision warning circuit with PIC16F887 and RS_232 serial port to send data using USART terminal for (short, middle, large) test range.A serial communication interface is used for sending the simulation results from MATLAB FMCW radar system to hardware easy PIC v7 board with PIC16F887 to forward collision warning circuit to alerts the driver of collision risk, Liquid Crystal Display (LCD) shows radar status (short, middle, large) in accordance to range between the vehicle that FMCW radar installed and the vehicle ahead.Graphic Liquid Crystal Display (GLCD) shows the car position and road lines. Piezo Buzzer will start singing to alerts the driver from danger road.The simulation design is achieving the desired performance, one parameter warrants further attention. In the FMCW configuration, the sweep time is about 25 microseconds. Therefore, the system needs to sweep a 140 MHz band within a very short period. Such an automotive radar may able to meet the cost requirement.

تقييم اداء الكشف المباشر والمتشاكه في نظام اتصال الليفة الضوئية == Performance Evaluation of Direct And Coherent Detections In Optical Fiber Communication System

Author name: علاء عبد الزهرة جعفر
Supervisor name: علي يوسف فتاح
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: تطورت خدمات الاتصالات بشكل متسارع في السنوات القليلة الماضية خصوصا في المسافات بعيدة المدى وبمعدل نقل البيانات بدقة عالية وخسائر قليلة في جميع انحاء العالم. وقدمت تقنيات مختلفة لزيادة سعة الارسال في انظمة اتصالات الالياف الضوئية بواسطة جمع مسارات البيانا | In recent years, there has been an extensive development of optical fiber services. They provide transmission over long distances at a high data rate with few losses all over the world. Different techniques have been introduced to increase the transmission capacity of optical fiber communication systems by a multiplexed high data rate stream into an optical fiber such as Dense Wavelength Division Multiplying (DWDM) technique. Since the deployment of DWDM technique, the focus on introducing large system capacity with high system performance, different detection techniques have been introduced to enhance the system performance with high sensitivity. In this work, two types of detection techniques (direct and coherent detection) have been evaluated and compared with each other. These detection techniques have been evaluated based on several models of encoding format such as Return to Zero - Differential Phase Shift Keying (RZ - DPSK) and Non Return to Zero - Differential Phase Shift Keying (NRZ - DPSK) at 10 Gb/s as a data rate.These systems were first simulated with a single channel to analyze the performance with no Stimulated Raman Scattering (SRS), Cross Phase Modulation (XPM) and Four Wave Mixing (FWM) effects. Whereby the system of 8×10 Gb/s is simulated at 200 GHz, 100 GHz and 50 GHz as channel spacing. Three types of dispersion compensation schemes are used in the link channel. These systems are simulated using (Optisystem version 10.0) software package. The performance of the designed systems are evaluated through Q.factor verses input power and Bit Error Rate (BER) verses Signal to Noise Ratio (SNR).The polarization interleaving is used with the WDM systems to decrease the nonlinear effects and the crosstalk arising among the adjacent channels.The obtained results of the 67% RZ - DPSK arrived to the threshold power at input power less than of the 50% RZ - DPSK, as well as the 50% RZ - DPSK system arrived to maximum Q.factor lower than 33% RZ - DPSK. This is due to the pulse duration of 33% RZ - DPSK is smaller than of 50% and 67% RZ - DPSK.The results show that the coherent detection technique has better performance than the direct detection technique. The coherent detection technique has Q.factor equal to 45, while the direct detection has Q.factor equal to 27 at the same input power ( - 5dBm), while the coherent detection technique arrived to the threshold power at the input power less than of the direct detection technique.The BER of the 33% RZ - DPSK with coherent detection with 10 Gb/s at 300 km as transmission distance achieved ?10?^( - 12.9) at SNR of 10 dB, while for the 33% RZ - DPSK with direct detection is achieved a BER of ?10?^( - 8.8) with SNR of 10 dB.The performance of the proposed systems has been improved extrusivly with increase the space channel, where the performance of the systems at 200 MHz as channel spacing has best performance than 50 MHz as channel spacing.By adapting coherent detection with 33% RZ - DPSK technique of 200 MHz as channel spacing, DWDM system can carry high data rate with long - haul transmission distance.

الشبكات المتعلمة الرقمية متعددة الاصناف المحورة لاغراض فحص كريات الدم الحمراء == Modified Multi - Category Digital Learning Network For Red Blood Cell Inspection

Author name: سهاد قاسم غلام حسين حداد
Supervisor name: محمود حمزة المفرجي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronic Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
Key words:
  • Pattern Recognition
  • RAM - based Weightless Neural Network
First pages:
Abstract: A pattern recognition system based on the n - tuple technique is developed and evaluated for use in classifying non - deterministic data with particular reference to medical image. The pattern recognition system presented in this work fulfills the requirements of simplicity and efficiency making it attractive to practical use in present day for industrial and medical environments. It is an effective solution for providing healthcare with reduced cost, especially for the rural areas and far away patients. Ordinary doctors (not specialist in blood diseases), will be able to perform extra - ordinary tasks.In this work Digital Learning Network has been designed for classification of different shapes of abnormal Red Blood Cells. Digital Learning Network is of low cost hardware and implementation, and one shot learning, using networks of RAMs. Many parameters have been investigated in details which affect the recognition rate. These parameters are presented to allow the system to be optimized, giving an increase in the performance of the system. Modification method of Feedback Digital Learning Network, which is an improving process of Digital Learning Network, has been implemented. The obtained results show that high performance (96.6%) can be achieved, providing evidence of the validity of the proposed technique.

اعادة تشكيل واضافة متسعات في قطاع توزيع كهرباء بغداد == Reconfiguration And Capacitor Placement In A Baghdad Distribution Sector

Author name: اديب ناصر حسين
Supervisor name: ثامر محمد عبد الوهاب
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering - Power and Machinery
Degree: Master
University: University of Technology - Electrical Engineering Department - Electrical Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: يعد تخطيط شبكات التوزيع الكهربائية من الاولويات في الوقت الحاضر في العراق نظرا للزيادة الهائلة في الاحمال الكهربائية والتوسعات المفروضة على الشبكات نتيجة التوسع العمراني الكبير والسريع.يتحقق الاداء الامثل للشبكة بتقليل المفاقيد‘ تحسين الجهد (Voltage pr | Planning of electrical distribution networks is considered of highest priority at the present time in Iraq, due to the huge increase in electrical power demand and expansions imposed on distribution networks as a result of the great and rapid urban development. Optimum performance of the electrical network is achieved by reducing losses, improving voltage profile and alleviating overload for the system components. Such operation provides for energy salvage and redundancy in the electrical network. A planning method is proposed in this work to achieve optimum operating conditions of the network by combining the network reconfiguration in conjunction with the insertion of capacitors of optimal sizing and locations. This method is classified as a huge discrete non - linear optimization problem due to the large number of variables along with the presence of constraints and objectives. The power losses and voltages in buses for all cases are obtained by backward/forward load flow method. The proposed planning of distribution networks is based on the powerful and advanced CYMDist software as a tool for the simulation of distribution networks and performing the required analysis. CYMDist is practical and efficient analysis software, which is used by many electrical companies worldwide as well as the Iraqi ministry of electricity.Optimal network reconfiguration and capacitor placement methods are tested on IEEE 33 - bus and IEEE 34 - bus test systems, respectively. The results show excellent matching as compared with previous work mentioned in the literature.The work is implemented on an actual sector from Baghdad city distribution network, which is Al_Bayaa 11kV, 145 bus, four feeders system. The presented results show that minimum active power losses with improved voltage profile had been achieved. So the network can operate normally without any constraints violation.

تحليل الاضطراب لتوربينة الرياح المربوطة مع منظومة القدرة == Disturbance Analysis of A Wind Turbine Connected With Power System

Author name: احمد نجم عبد الامير
Supervisor name: كنعان علي جلال
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering - Power and Machinery
Degree: Master
University: University of Technology - Electrical Engineering Department - Electrical Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: نظرا لزيادة الطلب على الطاقة في السنوات الاخيرة نتيجة للتوسع السكاني والصناعي ولتقليل التلوث الناتج من الوقود التقليدي والحفاظ على البيئة مما دعت الحاجة الى استخدام مصادر بديلة للطاقة, والتي يجب ان تمتاز بعدة ميزات اهمها انها صديقة للبيئة وغير قابلة للنفا | According to increasing the demand for energy in recent years as a result of the expansion of the population and to reduce pollution from conventional fuels, the need arises to find alternative sources of energy which must be characterized by several features, most important of which is friendly to the environment and sustainable. In this work, the effect of different types of disturbances on the performance of fixed speed of wind turbine generator type Squirrel Cage Induction Generator (SCIG) connected to the power system has been investigated, because it has features which make the best choice in some cases, despite the less efficiency compared with other types of generators. Also, this work aims to study and analysis the effect of (STATCOM) on the wind turbine generators because of its advantages in improving voltage stability of the grid and improving the quality of the productive power. The proposed work is performed using MATLAB/Simulink. The intelligent systems have been used to obtain the best performance in terms of extracting more power from wind energy as well as increase the stability of system in situations of disturbances and the results obtained have been compared with conventional control systems.Three types of controllers are proposed in this work; the first controller is the Proportional - Integral (PI) based on classical trial and error method, the second controller is PI - controller based on Particle Swarm Optimization (PSO) technique for optimal tuning (gain) to improve the performance of the system. The results obtained proved that the PI - controller based on Particle Swarm Optimization (PSO) technique is better than based on trial and error method. The third controller is (Nonlinear Auto regressive - Moving Average) NARMA - L2 based on (PSO). Finally, the results of the proposed controllers show that NARMA - L2 controller is more effective on the stabilization and improves the performance of the system compared with PI - PSO controller

تقييم اداء المسافية بوجود اجهزة FACTS == Distance Protection Performance Evaluation In Presence of Facts Devices

Author name: امير عقيل محمد
Supervisor name: قيس متي الياس
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering - Power and Machinery
Degree: Master
University: University of Technology - Electrical Engineering Department - Electrical Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: With limited enhancement or expansion of the transmission infrastructure, the contemporary power systems are operating under more stressed conditions. It becomes important to fully utilize the existing transmission system to supply load demand as much as possible, thus eliminating or reducing the need for new transmission investment. Flexible AC Transmission System (FACTS) technology provides a method to fully utilize the existing transmission lines as well as new and upgraded lines. However, the implementation of FACTS devices in the transmission system has introduced new power system dynamics that must be addressed in the area of power system protection, such as rapid changes in line impedance, line current and voltage. This thesis reports the results of comprehensive study carried out to explore the impact of mainly two of the FACTS devices, Static Synchronous Compensator 'STATCOM' and Unified Power Flow Controller 'UPFC', on the distance protection relaying system in order to identify important issues that protection engineers need to consider, that is during the stages of design and operation of the protection system. Simulation studies are carried out using MATLAB/SIMULINK. First, the distance relay has been modeled and validated with FACTS device models using test systems from literature. Then the distance relay performance is analyzed and evaluated for various fault and loading conditions in the presence of FACTS devices. A comprehensive study and results for one of the Iraqi 400kV transmission lines (KDS4 - NSRP transmission line) are presented and useful recommendations can be presented to the General Directorate of electrical Power Transmission for Middle Euphrates region / Iraqi Ministry of Electricity. II Abstract Generally, the results show that the apparent impedance seen by the distance relay would be different from that of the system without FACTS devices. Due to this, the distance relay may malfunction, resulting in undependable operation of the power system protection during faults. Furthermore, the results show clearly the dependency of the distance relay operation on many design and operational factors. These include the FACTS device type and its use purpose, the FACTS device connection point or location, the fault type and fault point location along the line, the power flow,...etc.

تحسين استقرارية منظومة الشبكة العراقية (kV 400) باستعمال افضل جهاز من اجهزة ال FACTS == Stability Improvement of The (400kV) Iraqi Grid Using The Best FACTS Device

Author name: شيماء شكري عبد الحليم
Supervisor name: رشيد حميد الربيعي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering - Power and Machinery
Degree: Master
University: University of Technology - Electrical Engineering Department - Electrical Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: يعتبر نظام القدره الكهربائيه من الانظمه الضخمه والمعقده لاحتوائها على عدد كبير من محطات التوليد وخطوط النقل واجهزة السيطرة لذلك فانه يخضع الى تغيرات مفاجئه في مستويات الحمل، حيث اصبح من الصعب جدا الحفاظ على نظام مستقرمع التغيرات التي يشهدها النظام, لذلك | Electrical power system has become large and complicated so it is susceptible to sudden changes in load levels. Stability is an important concept which determines the stable operation of power system.The modern trend is to employ Flexible Alternating Current Transmission System (FACTS) devices in the system for effective utilization of transmission resources. The FACTS devices contribute to power flow improvement besides they extend their services in transient stability improvement as well, study and analyze the stability of system through rotor angle and voltage. The objective of this work is to improve the transient stability of the Iraqi National Super Grid System (INSGS) by using best FACTS device in different optimal locations under fault conditions. Two test systems are studied, the first system is IEEE 9 - bus test system, and the second system is the Iraqi (400 kV) electrical network 24 - bus bars, three phase to ground fault, temporary fault and permanent fault are tested. The load flow program was implemented using Newton - Raphson method and the numerical solutions of non - linear differential equations are solved using Trapezoidal method. The programs that are used in this work are implemented using MATLAB 7.12.0(R2011a) package based on Power System Analysis Toolbox (PSAT version 2.1.6)software.copyright © 2002 - 2010 by Federico Milano as Graphical User Interface. A comparison has been made between five types of FACTS (UPFC, SSSC, TCSC, SVC, STATCOM) at optimal locations of the Iraqi grid and 9 - bus test system to get optimal FACTS devices by (voltage stability and rotor angle stability). The results obtained show that Unified Power Flow Controller (UPFC) is an optimal device for improvement the stability by damping the voltage and rotor angle oscillations.

التركيب السليكوني النانوي في الخلايا الشمسية == Nanostructured Silicon Based On Solar Cells

Author name: نور احمد سلمان
Supervisor name: ثائرة زكريا الطيار
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronic Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: تعتبر الخلايا الشمسية تكنولوجيا واعدة وقابلة للتجديد حيث ازداد الطلب عليها نتيجة لزيادة الاهتمام بالطاقة الكهروضوئية. ان التحسين المستمر لكفاءة الخلايا الشمسية بايجاد التقنيات والمفاهيم الجديدة يجب ان يمتد على نحو متزايد باعتبارها واحدة من اهم مصادر الط | The demand for solar cells has been growing rapidly with an increasing social interest in photovoltaic energy. The improvement of energy conversion efficiency of solar cells is performed by developing the technology and concepts that have been increasingly extended as one of the key components in our future global energy supplement. But, the main problem of photovoltaic modules are their rather high production and energy cost. Three generations of solar cell technologies have been established in the previous century.Nanostructured silicon substrates based on p - type crystalline Silicon (c - Si) have been prepared in this work. Electrochemical Etching (ECE) of the Silicon (Si) wafers in Hydrofluoric (HF) acid was employed to synthesize porous layers consisting of silicon nanostructures. The process was carried out at different etching time and different current densities which are considered as effective parameters in ECE process. It is found that a homogeneous porous layer could be obtained with porosity value of (87%) when the current density is (60 mA/ cm2) and the etching time of (10 min). Among the Transparent Conductive Oxide (TCO) materials available, Zinc Oxide (ZnO) films show promising electrical and optical properties in combination with low cost alternatives. It can function as Anti - Reflecting Coating (ARC), window material, transparent electrode and active layer in heterojunction solar cells. n - type ZnO thin films are grown on p - type nanostructured silicon substrates by using Pulsed Laser Deposition (PLD) technique with Q - switching Nd : YAG laser beam Second Harmonic Generation (SHG) [?=(532 nm), number of pulses (140) pulses, and laser energy (820 mJ)], vacuum of (10 - 3 Torr), ambient oxygen pressure of (10 - 1 Torr), and substrate temperature of (400 °C). The morphological, optical, chemical and structural properties were investigated using Atomic Force Microscopy (AFM), Ultraviolet - Visible (UV - VIS) spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, and X?Ray Diffraction (XRD) techniques, respectively.Surface morphology and optical properties results show densely packed highly crystalline growth of ZnO thin film on nanostructured silicon substrate grown at optimum condition with an average grain size around (88.57 nm). The average roughness, root mean square, and ten - point height estimated from AFM quantitative analysis, are found to be (3.02 nm), (3.62 nm), and (8.76nm) respectively. The thickness is calculated and found to be (100 nm). The film shows high transparency (above 80%) and the estimated Energy - gap (Eg) is found to be about (3.4 eV). This is important for its applications as transparent conductive films and solar cell windows. The chemical and structural properties results characterize ZnO at (420 cm - 1) and (766 cm - 1) absorption bands respectively and the thin film is polycrystalline with hexagonal Wurtzite structure.

تصميم وتنفيذ ذراع الي موجه عن طريق اشارة تخطيط العضلات باستخدام المتحكم الدقيق == Design And Implementation of A Robot Arm Driven By EMG Signal Based On Microcontroller Unit

Author name: انس عبد الحميد كاظم
Supervisor name: خالدة شعبان رجب
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronic Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: تعتبر اشارة (EMG) هي الاشارة المكتشفة على سطح الجلد فوق العضلة والمتولدة من مصدر المجال الكهريائي عند التقلص العضلي. الاشارة العضلية بصورة رئيسية في مجالين : تشخيص الخلل العضلي واشارة تحكم لسياقة ذراع الي، يستخدم الذراع الالي المساق بواسطة الاشارة العضلي | Electromyogram (EMG) is a signal detected on the skin above a muscle and generated by sources of electric field within the muscle during contraction. EMG signal is used mainly in two fields; Muscle disorder diagnostic and control signal for driving robotic arm. The robot arm driven by EMG is used as a remote control in hazard places or as prosthesis part for limbs of disabled. The first part presents placing array of EMG electrode on two muscles and measure the EMG signal, design acquisition circuit to optimize the EMG signal for two muscles; hardware circuit that designed will eliminate the noise resulting from cable, electrodes, 50Hz and aliasing. In order to monitor and record EMG signal, Data Acquisition System (DAQ) is designed for this purpose using Arduino platform, which gives the ability to deal with signal. The real time signal was taken from three persons with different weights and ages. The second part includes a proposed design of digital filter with windowing and applying to real time signal to compare the results for many times of orders and types of windowing in order to meet the best criteria. The FIR filter with 8th order will be chosen as digital filter with Hann windowing that is apply to eliminate the EMG noise that is caused from many sources and results optimum EMG signal that is used to control robot arm, implementing digital filter characteristic into dsPIC30F4013 which it signal processing microcontroller and using the filtered signal to control the robot arm by interfacing with DC driver to drive robotic arm with two degrees of freedom (2 - DOF). Also, this part includes the technique which simulates the results using MATLAB 2011a to control the movements of the robotic arm. Micro C for dsPIC© is used to write C code for FIR digital filter and loops with control algorithm to enable the controlling robot arm.

تقليل التاثيرات اللاخطية في منظومات التقسيم المتعدد للطول الموجي العالية الكثافة == Mitigation of Fiber Nonlinearity Effects In Ultra High - Dence WDM System

Author name: سيف حسام عبد الواحد
Supervisor name: علي يوسف فتاح
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: The optical signal is severely degraded when transmitted in the fiber due to both the linear and nonlinear distortions. It is well known that, the linear distortions in single mode fiber include chromatic dispersion (CD) and polarization - mode dispersion (PMD) while self - phase modulation (SPM), cross phase modulation (XPM) and four - wave mixing (FWM) are considered the most among nonlinear distortions. To deal with the nonlinear impairments, a number of techniques, such as electronic equalization, pre - coding, digital back - propagation(BP), pre - chirping, optical phase conjugation (OPC) and nonlinearity management, are developed and improved. In the present work, a method called Fractional Fourier Transform (FRFT) has been applied to mitigate fiber nonlinearity impairments. The Fractional Fourier Transform is a time - frequency distribution and an extension of the classical Fourier transform. Time domain FRFT can be implemented by using time lens according to the optical time - space duality theory. The modulated optical pulses will be pre - distorted by an FRFT module before being launched into fiber links. In this work, 10 Gb/s optical fiber system with five spans, each of length 60 Km, for three types of modulation formats (Return - to - Zero Differential Phase Shift Keying (RZ - DPSK), Return - to - Zero Differential Quaternary Phase Shift Keying (RZ - DQPSK) and Carrier - Suppressed Return - to - Zero (CSRZ)), single and multi - channel transmission systems are designed and simulated using “OptiSystem (2011) version 10.0” software package. In order to analyze the transmission performance of the simulated systems without and with FRFT, a set of eye diagrams, optical spectrum visualizers, Q - factor versus input power and Bite Error Rate (BER) versus Signal to Noise Ratio (SNR) curves are presented to evaluate the influence of FRFTon the system performance. For CSRZ modulation format the Q - factor for single channel system at 0 dBm (input power) was 43.5 without FRFT and 78 with FRFT. The BER of sixteen channel system (channel No.8) at bit rate 10 Gb/s per channel, 300 Km link length of CSRZ modulation format with channel spacing of 50 GHz at SNR 10 dB without FRFT is 10 - 4.8 and 10 - 7.4 with FRFT. The BER of thirty two channel system (channel No.16) at bit rate 10 Gb/s per channel, 300 Km link length of CSRZ modulation format with channel spacing of 50 GHz at SNR 10 dB without FRFT is 10 - 4.6 and 10 - 6.4 with FRFT. The BER of thirty two channel system (channel No.16) at bit rate 10 Gb/s per channel, 300 Km link length of CSRZ modulation format with channel spacing of 25 GHz at SNR 10 dB without FRFT is 10 - 2.56 and 10 - 3.24 with FRFT.

خوارزمية جديدة لنظام اخفاء المعلومات == New Algorithm For A Steganography System

Author name: مروة جليل محسن
Supervisor name: اثير علاء صبري
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: This thesis presents a new steganographic algorithm for embedding encrypted secret image in grayscale and color images to provide high level security of data for communication over unsecured channels.The proposed algorithm combine the features of Cryptography and Steganography. The hidden secret message capacity, stego - image quality and security are three important conditions for data hiding technology. According to these requirements, an effective security protection with high hiding capacity steganographic algorithms are proposed based on frequency domain of the cover and the secret image.The proposed algorithm first analyzes the secret image into its frequency components using Discrete wavelet transform (DWT) , Wavelet packet transform(WPT) , Multiwavelet transform(MWT) , and slantlet transform(SLT) , respectively. Then the low frequencycomponent of the secret image is encrypted using Advanced encrypted standard (AES) method and then embedded in the insensitive mid and high sub - bands obtained from the cover image after applying these transformations (mentioned earlier) on it. The embedding method used in this thesis is LSB (Least significant bit ) method. The resulting stego image from different algorithms are then compared..The effectiveness of the proposed algorithm has been estimated by computing Mean square error (MSE) ,signal to noise ratio (SNR), Peak Signal to Noise Ratio (PSNR) and the capacity.The best algorithm is obtained by using 2level - DWT for cover image and 1level - DWT or WPT for secret image because the capacity of the hidden secret data and stego image quality are improved. The embedding image reaches to half the size of cover image at same time PSNR reach to 62 dB and MSE about 0.036 and this is better than many other existence algorithms.By both objective and subjective observations, the resultant stegoimage that will be transmitted does not draw any suspicion, so the main goal of steganography is achieved..The language used for testing the algorithms is MATLAB R2013a, with a computer of the following specification ; Processor : Intel(R) Core(TM) i5 CPU M430 @ 2.27GHz and RAM - 3GBytes.

اخفاء العلامة المائية الرقمية باستخدام تحويل الموجيات ذات عامل جودة قابل للتعديل == Digital Watermarking Based On Tunable Q - Wavelet Transform

Author name: هاجر احمد ابراهيم
Supervisor name: اثير علاء صبري
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: لقد دخلنا عصر حيث المعدات غير المكلفة متوفرة ويمكن من خلالها انتاج نسخ كاملة من المواد المتعددة الوسائط الرقمية مثل صوتيات بجودة القرص المضغوط ونشر صور عالية الجودة او مقاطع الفيديو الرقمية. من خلال هذه البيئة اصبح من السهل على الجهات غير المختصة انتاج ن | We have entered an era where inexpensive and readily available equipment can produce perfect copies of digital multimedia materials, such as CD - quality audio, publication - quality images, or digital video. In this environment, it has become easier for malicious parties to make salable copies of copyrighted content without compensation to the content owner.Many media content owners are concerned about the potential loss of revenue from multimedia piracy, especially when the content will be exposed to the Internet. Digital watermarking is seen by many as a potential solution to this problem.In this thesis, two proposed methods one for grayscale image watermarking and the other for color image watermarking are suggested. They require the original image for watermark extraction and they are belonging to the wavelet domain watermarking. They exploit the Tunable Q_Wavelet Transform. Therefore, different cases are performed to identify the best among them for the proposed application. As a result of the testing process, the best case is founded when ( Q=4, r=8, J=28). The first proposed method can be used with applications requiring high degree of imperceptibility and high security. The embedding process of this method is based on adding the pseudorandom watermark bits in the largest TQWT coefficient.The second proposed method is more robust against distortions than the first proposed method and is characterized by an acceptable degree of imperceptibility and high security. The embedding process of this method is based on adding the compound watermark image to the original color image.They are performed using MATLAB7 programming language. Different images are tested and the watermark is extracted exactly from the watermarked images.The Peak Signal to Noise Ratio “PSNR” using best case for the two proposed methods is found (77.97) dB for the first method and (51.14) dB for the second method.

تحديد منظومة كفوءة للقدرة الفوتوضوئية المستقلة بناءا على الاجواء العراقية == Investigation Into Efficient Stand - Alone Photovoltaic System Based On Iraq Climate

Author name: انسام صبحي جبار
Supervisor name: محمد مؤنس عز الدين
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering - Power and Machinery
Degree: Master
University: University of Technology - Electrical Engineering Department - Electrical Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: الطاقة الشمسية هي احدى الطاقات المتجددة التي تمتاز بانها امنة وصديقه للبيئة. عالميا هناك توجه كبير لهذة الانواع من الطاقات للحد من مشاكل التلوث والاحتباس الحراري. شهدت السنوات الاخيرة انخفاض في اسعار منظومات الطاقة الشمسية وكذلك ارتفاع كفائتها مما ساعد وب | Solar energy is safe as well as clean. It is one type of renewable energy , the energy does not cause pollutions and is not harmful to the environment. It is gaining importance now with the increases in global warming and pollution causing the adoption of renewable energy sources as alternative energy sources. For these reasons, the technological advance seeks to reduce the cost of renewable energy and increase efficiency to expand its reach.This work investigates the best strategy for design the solar energy system of stand - alone type. The stand - alone system consists of the PV array, maximum power point tracking, DC - DC converters, charge controller, battery, load and inverter. Standard specifications are used to ensure the successful operation of any system designed according to this method.The proposed method in this work includes calculation by using Microsoft Excel and simulation of long term periods especially during the autonomy days operation by using Matlab/Simulink. Many cases are studied, a suitable PV power system is introduced for each case. The results of the design of the case study are quite in agreement with published results.The objective of this work is to design solar energy systems for hypothetical loads according to Iraqi climate, this aim is achieved because the designed system passed many tests, especially for the worst case of operation. The investigation shows that the system is capable of exhibiting a reliable operation for any weather condition.

تصميم مضخمات قدرة راديوية التردد بتقنية CMOS مع محولات جامعة للقدرة == Design of RF Power Amplifiers With Power Combining Transformers

Author name: سهاد حسين جاسم
Supervisor name: احمد سعدون عز الدين
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronic Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: باستخدام تقنية CMOS، تواجه تكامل مضخمات القدرة العديد من التحديات بمستوى الواط والمستخدمة لتطبيقات الاتصالات اللاسلكية. وللتغلب على هذه المحددات، يمكن استخدام عدد من الوسائل واطئة الفولتية ودمجها بكفاءة باستخدام المحولات على الرقاقة لزيادة قدرة الخرج النا | In CMOS technology, many challenges face the integrated watt level power amplifiers (PAs) used in wireless applications. Consequently, to overcome these limits, several low voltage devices should be combined efficiently with on - chip transformers in order to increase the resulting output power. In this work, two high - performance Radio - Frequency (RF) power amplifiers for watt level applications are designed and simulated in deep submicron (0.13 µm) CMOS process technology using “Agilent Advanced Design System ADS 2011.10 with “BSIM4” as a simulation module for Metal - Oxide - Semiconductor Field - Effect Transistor (MOSFET) devices. The design includes a comparison for the conventional transformer combining techniques SCT, PCT and the hybrid type PSCT. The amplifiers incorporate a parallel combination of four differential PA cores to generate high output power with good efficiency and linearity. The first part of the work presents a design for a watt - level class - AB power amplifier based on transformer type power combiner PSCT for WLAN applications. The PA delivers an Output Power (Pout) of 30 dBm, Power Gain (Gp) of 30 dB and 40% Power Added Efficiency (PAE) under 2.5 V supply. In the second part of the work, a class - E PA based on transformer type power combiner PSCT is designed. The power amplifier provides an output power of 30 dBm, power gain of 30 dB, and 54% PAE at 2.45 GHz under 1.6 V supply. Finally, in the third part of this work, an on - chip output transformer layout for the proposed power amplifiers is designed and simulated with momentum RF EM simulator of ADS 2011.10 in order to realize a fully integrated power amplifier. The simulated efficiency of the PSCT was 78% with minimum insertion losses (ILmin) 0.87 dB.

تصميم متحكم ذكي لنظام تتبع شمسي بالاعتماد على مصفوفة البوابات الرقمية القابلة للبرمجة == Design of Intelligent Controller For Solar Tracking System Based On FPGA

Author name: ياسر محمد عبد
Supervisor name: حنان عبد الرضا عكار
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronic Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: ان الحاجة لزيادة توليد الطاقة الكهربائية جعل استخدام الخلايا الشمسية تلعب دورا هاما في الحياة اليومية، وعليه من المهم استخدام نظام يسمح بتتبع الخلايا الشمسية لضوء الشمس لزيادة او الحصول على القيمة المثلى للطاقة الكهربائية من الخلايا الشمسية. تم في هذا ا | The need to increase the energy generation makes the use of solar cells plays an important role in the daily life. For this reason, it is important to use solar tracking system to increase or getting almost optimum value from solar cells. In this thesis, solar cells model was implemented using MATLAB to show the characteristics of any solar cell depending on data sheet. Intelligent controllers was designed and used to make solar cells facing the sun all days. The proposed controller was trained by two ways; the first was trained by supervised feed forward neural network and the second by Particle Swarm Optimization (PSO) and then comparing the results obtained. The controller was trained using MATLAB and the converting it to simulink model in order to test it, and converts, it to a Very high speed integrated circuit Hardware Description Language (VHDL) language using MATLAB tool box in order to download it on Spartan 3A Field Programmable Gate Arrays (FPGAs) card. This makes the implementation of the intelligent controller more efficient and easy to use because of its reprogram - ability and the high speed performance. The controller was designed to a fully controlled DC motor driver which is used to rotate two DC motors in X - axis and Y - axis directions respectively.The experimental results show that tracking sun increases the efficiency of the system to produce energy from solar cell about 44.3778 % more energy than the solar cell without tracking system.

نظام كشف وتمييز لوحة الرخصة للسيارات العراقية == License Plate Detection And Recognition System For Iraqi Cars

Author name: ثائر عذار هاشم
Supervisor name: اياد ابراهيم عباس
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronic Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: نظام كشف وتمييز لوحات ارقام السيارات هو تقنية في معالجة الصور يستخدم للتعرف على السيارات من خلال لوحات الارقم الخاصة بها, او بكلمات اخرى هي تقنية تستخدم لتحويل نص صورة لوحة ارقام السيارات الرقمية الى ملف نص ممكن ان يحرر ويستخدم في اي برنامج او تطبيق اخر | Automatic License Plate Detection and Recognition (ALPDR) system is an image processing technology used to identify vehicles by their license plates, or in other words, is a technology used to convert the text on digital images of vehicle license plates to a text file that can be edited and used as such by any other program or application that needs it.License Plate Detection and Recognition system for Iraqi cars have a wide range of applications; it is used to extract plate number to create automated solutions for various problems. Among these applications : parking, border crossing, traffic control, access control and stolen cars tracking.This system consists of two main parts : the first is a practical implementation of how to take a picture automatically for cars passes, this was done by two sensors type (GP2Y0A21YK0F sensor) connected with each other and interfaced with a camera (A4tech USB camera), this camera is interfaced using Matlab with the PC. The camera is attached using USB port. The second part is image processing, this part includes four basic stages : The first stage is image preprocessing which involves image normalization and RGB to gray image conversion. Second stage is detection of a possible license plate using edge detection technique and extracts these LP using region growing technique, detection rates reach to 95%. Third stage is alphanumeric character segmentation to isolate each character, numbers and words of the license plate using Otsu's and Hough transforms technique for subsequent recognition. The last stage reads the alphanumeric character and words by correlation template matching, which is a simple, fast and given a recognition rate reach to 98.245%.

تعزيز اداء اتصالات الراديو عبر الليف احادي ومتعدد الطول الموجي بواسطة تقنية التضمين == Performance Enhancements of Single And Multi - Wavelength Radio Links Over Fiber By Modulation Technique

Author name: مصطفى عبد الهادي جليل
Supervisor name: عايد خلف محمد
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
Key words:
  • Radio - over - Fiber (RoF)
  • Quadrature Phase Shift Keying (QPSK)
  • Quadrature Amplitude Modulation (QAM)
  • Orthogonal Frequency Division Multiplexing (OFDM)
  • Digital Signal Processing (DSP) Unit
First pages:
Abstract: تم تطوير تكنولوجيا الراديو عبر الالياف منذ اواخر القرن العشرين، وتم استخدامها في مجموعة من التطبيقات لانظمة الاتصالات ويعتبر الراديو عبر الالياف هو الجيل المقبل من انظمة الاتصالات لما يمتاز به من العديد من المزايا مقارنة مع النظام التقليدي مع توهين منخفض | Radio - over - Fiber (RoF) technology has been developed since the late 20th century and has been used efficiently in a range of applications for communication systems. Radio over fiber system is the next generation of communication systems because it has many advantages compared with conventional system with low attenuation, enormous bandwidth of optical fiber, and extension of existing coverage and capacity. RoF system refers to the radio signals which are modulated with optical signal and transmitted over optical fiber link from Central Office (CO) to the Remote Nodes (RNs).In this work, several RoF systems have been designed and simulated with different modulation techniques using commercial software package called “Optisystem v.12”. Furthermore, these systems were compared with each other to check for better performance. These systems are presented as follows : The first system is RoF with Quadrature Phase Shift Keying (QPSK), 16 - Quadrature Amplitude Modulation (16 - QAM), and 64 - QAM schemes with and without OFDM technique. The simulation results of this system show that the Signal to Noise Ratio (SNR) for 64 - QAM - OFDM higher than SNR for QPSK, 4 - QAM and 16 - QAM with OFDM at 10 - 9 symbol error, after 50 km of SMF length without any amplification or compensation techniques. In addition, also SNR for 64 - QAM - OFDM higher than SNR for other techniques in this work after 160 km of fiber length.The second system is the RoF with QPSK and 16 - QAM schemes with Digital Signal Processing (DSP) unit in the receiver side. The simulation results of this system show that the Error Vector Magnitude (EVM) for QPSK scheme with DSP unit is 14.5% and 85.5% without DSP unit after 50 km of fiber length. Furthermore, the EVM for 16 - QAM with DSP unit is 7.5%, but the EVM for the same system without DSP unit is 91%. In addition, the EVM for QPSK with DSP equal to 11.5%, but the EVM for 16 - QAM with DSP equal to 9% after 160 km of fiber length.The third system is RoF system with two multiplexing techniques, 8×10 Gbps WDM - RoF system and 4×5 Gbps SCM - RoF system, have been simulated with 4 - QAM - OFDM, 16 - QAM - OFDM and 64 - QAM - OFDM schemes. The fourth system was to combine the techniques of wavelength division multiplexing (WDM) and subcarrier multiplexing (SCM) to increase the capacity of the system by 20×8 Gbps data rate. The simulation results show that the SCM - WDM - RoF with 64 - QAM gives high SNR compared with SCM - WDM - RoF system with other modulation schemes which have been used in this work.

تحسين الاستقرارية باستخدام التوليد الموزع في شبكة النجف الاشرف الكهربائية == Stability Enhancement Using Distributed Generation In Al - Najaf Al - Ashraf Electrical Network

Author name: زيد طارق حسن
Supervisor name: رشيد حميد الربيعي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering - Power and Machinery
Degree: Master
University: University of Technology - Electrical Engineering Department - Electrical Engineering Branch
Language: English
University location: Baghdad
First pages:
Abstract: ان عمل وتركيب نظام التوزيع يتغير مع اضافة وحدات التوليد الموزع (DG )، حيث انها تؤثر على خسائر القدرة، الاستقرارية، الفولطية، جودة الطاقة وكميات اخرى، لذلك اختيار الموقع الامثل والحجم وعدد وحدات التوليد الموزع (DG ) ضروري لتجنب التاثيرات السلبية على نظا | The operation and structure of distribution system are changing with the integration of distributed generation (DG), where the DG may have effect on power losses, stability, voltage profile, power quality and other quantities, therefore the optimization of location , size and number of DG are necessary to avoid the negative impacts on electric power system.In this work, the Particle Swarm Optimization (PSO) technique is used to find the optimal number and locations of DG in order to minimize the active power losses. The thermal limit of transmission lines and transformers was studied in cases , with DG and without DG, to detect the lines or transformers which exceed the limit in order to processed it. The voltage stability of distribution network has been investigated, using L index (which aims to detect the vulnerable load buses of an electrical power system). Also the rotor angle transient stability of DG units has been calculated to specify the critical clearing time (CCT) of each circuit breaker in distribution network when one of transmission lines is exposed to three phase to ground fault. The developed algorithm has been verified using two test systems IEEE 33 - bus distribution system and the WSCC 9 - bus test system, furthermore applied to a part of Iraqi distribution network (Al - Najaf Al - Ashraf distribution network). Two softwares are used in this work , the first is Matlab R2013a for implementation of the PSO and voltage stability algorithms while the second software is Power World Simulator 15 for implementation of the thermal limit of transmission lines and transformers, and rotor angle transient stability of DG units.DG contributed significantly to reduce the power losses in Al - Najaf Al - Ashraf distribution network, where there is a reduction by about 96% in active losses. Also DG processed the overload of large substations and the stability of buses in the network.

تصميم وتصنيع والتحقق من الخلية الشمسية ذات الصبغة الحساسة للضوء == Design, Fabrication And Verification of Dye Sensitized Solar Cell DSSC

Author name: صابرين سمير حسان
Supervisor name: ثائرة زكريا الطيار
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronic Engineering
Degree: Master
University: University of Technology - Electrical Engineering Department - Electronic Engineering Branch
Language: English
University location: Baghdad
Key words:
  • Dye sensitized solar cells
  • natural dyes
  • synthetic dye
First pages:
Abstract: Solar cells are considered a promising technology and renewable, in view of increasing in the electro - optical energy. The continual enhancement in solar cell efficiency by searching for new concepts and techniques, which should grow since it is considered as one of the important sources of energy of the future.This work introduces a type of solar cells that employs photosensitive organic dye. These cells use thin membrane of Titanium dioxide material as nanoparticles covered by an organic dye, which absorbs solar energy (like the chlorophyll in green leaves) to be converted into electrons that are injected into the Titanium dioxide layer, which serves as electron collector. In addition, it has an electrolyte solution to compensate for the electrons lost by the organic dye molecules.The cell's positive terminal was prepared from the deposition of a thin membrane of Titanium dioxide, of 22 micrometer thickness on a conductive glass electrode , followed by heat treatment at 450? for 30 minutes. Three organic dyes were used, two of (Cherry juice mixed with Hibiscus and the Berries juice) which were natural dyes, and the other synthetic, the "Eosin" as an industrial dye. Small quantities of Iodine and Potassium Iodide were dissolved in Ethyl Alcohol of 99.9% concentration in order to prepare the electrolyte solution. As to the negative terminal, it was prepared from the deposition of a graphite layer, used in pencils, onto a conducting glass electrode. The final stage involved the assembly of the different prepared cell components and tested.The equipment used in this work included spectrum analyzer for provision of absorption spectra for the three dyes.The cells have been tested by exposure to light of 100W/cm2 to obtain I - V characteristic curve and the greatest current is obtained with the Cherries and Hibiscus cell was 6.205 mA/cm2 and the maximum voltage 0.569 V. As to the Berries dye cell, the maximum current is found 4.35 mA / cm2 and its maximum voltage 0.607 V. The maximum current and voltage for the Eosin dye cell are found to be 1.32 mA/ cm2 and 0.651V.The conversion efficiency for the Cherry and Hibiscus dye cell is found to be 1.9%, the Berries dye cell 1.5% and for the Eosin dye 0.5%.
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