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تبؤ الاحمال الكهربائية للشبكة العراقية للمدة القصيرة باعتماد نظام المنطق الضبابي == Short - Term Electrical Load Forecasting For Iraqi Power System Based On Fuzzy Logic System

اسم المؤلف: هدى منهي عبد العباس
اسم المشرف: Firas Mohammed Tuaimah
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الكهرباء
الدرجة: ماجستير
الجامعة: جامعة بغداد - كلية الهندسة - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Load forecasting is used by participants in electric energy generation, transmission, distribution, and marketing for a variety of decision - making processes, such as economic dispatch, unit commitment, hydro - thermal coordination, transaction evaluation, and expansion planning. However, the need for accurate forecasts has intensified in the last decade due to the energy industry deregulation. Taking this into account as well as the rapid fluctuations in demand and abrupt changes in weather condition, access to reliable models for accurate forecast of load demand is essential. Due to the need for accurate load forecasts, numerous statistical and artificial intelligence methods have been proposed for the short - term load forecasting problem.In this study, the Multiple Linear Regression (MLR) method, which is one of the statistical methods, and an Interval Type - 2 Takagi - Sugeno - Kang Fuzzy Logic System (IT - 2 TSK FLS), which is one of the artificial methods and an extension of the conventional fuzzy logic system, were applied. Developed models were trained using the genetic algorithm. With the purpose of an objective assessment, the available dataset was split into training samples (80%, ????????????) and test samples (20%, ??????????). The training data used in this study covered the period from January 1, 2012 to February 1, 2012 for winter season and the period from July 1, 2012 to August 1, 2012 for summer season. The actual load forecasting period started from January 22, till 28, 2012 for winter model and from July 22 till 28, 2012 for summer model.This work suggested two models; the first model was for hourly (24 hour) load forecasting for one day ahead and the second model was for one week ahead in hourly forecasting (from one until 168 hour). For each model, winter and summer seasons were presented. The Main average percentage error (MAPE) term is an index that provides information about the bias of the model and how close forecasts or predictions are to the eventual outcomes. Experiments conducted with real datasets for the Iraqi power system showed that IT2 TSK FLS models precisely approximated future load demands with an acceptable accuracy.The real data for Iraqi power system were taken from Iraqi Operation and Control Office which belongs to the Ministry of Electricity.A computer program, written in MATLAB programming languages, was developed to represent the proposed method.

تحسين تخطيط المسار للروبوتات المتنقلة والمستقلة بالحركة باستخدام خوارزميات الامثلية القائمة على مبدا التجمعات == Improvement of Path Planning For Autonomous Mobile Robots Using Population - Based Optimization Algorithms

اسم المؤلف: فرح مهدي علي
اسم المشرف: نزار هادي عباس
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الكهرباء
الدرجة: ماجستير
الجامعة: جامعة بغداد - كلية الهندسة - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Autonomous mobile robots are used in various applications such as dangerous regions. These applications demand robust and adaptable methods for path planning.Path planning optimization problem is a fundamental problem for robot navigation; its purpose is to find a collision - free path from the initial position to a target position. Many real - world optimization problems have become increasingly large, complex and dynamic, which require the development of methods and solutions whose efficiency ismeasured by their ability to find acceptable results within a reasonable amount of time.The Artificial Bee Colony (ABC) and Bacterial Foraging Optimization (BFO) algorithms are used for solving hard optimization problems, including path planning. BFO algorithm is a simple and powerful searching technique. On the other hand, Artificial Potential Field (APF) as a real time obstacle avoidance method is quite simple in theory, but it is easy to bring local minimum problem and failing to find a path in the narrow channel. Therefore, a method for hybridizing APF with BFO is introduced to make use of both methods' advantages. This thesis presents efficient and reliable four optimization algorithms to solve the path planning problem. The first two algorithms are developed based on ABC algorithm as global path planning; they specifically are modified version of ABC algorithm called Directed ABC (DABC) algorithm and a new fitness function added to ABC algorithm named Minimum Angles (MAABC) algorithm was developed. The other two algorithms were proposed based on BFO and APF algorithms as local path planning; they were namely improved versions of BFO algorithm with adaptive step size (ASBFO) algorithm and a proposed version of BFO algorithm with an adaptive tumble (ATBFO) algorithm.The developed algorithms were simulated using MATLAB R2011b package. The simulation results showed that these algorithms could find the shortest paths for even crowded environments. Moreover, these algorithmswere compared with other researchers’ work to evaluate their performance. Additionally, a comparison was made between the executing time of the proposed local path planning algorithms (ASBFO and ATBFO algorithms) and the real tracked military robot (e.g., Talon) to verify the capability of the proposed methods. Both algorithms achieved fast run time, approximately three times faster than Talon for complex environment, which made them practically efficient.

تجزئة الحزمة لالغاء الضوضاء المتكيف في تنقية الاشارة الكلامية == Subband Decomposition For Adaptive Noise Cancellation In Speech Enhancement

اسم المؤلف: حوراء فاضل عبيد
اسم المشرف: منال جميل الكندي
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية الهندسة - قسم الهندسة الالكترونية والاتصالات
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Nowadays speech processing methods are usually implemented in the time or frequency domain. Filter bank can be considered as a divide and conquer approach within signal processing, since large problems are sub - divided into many smaller problems. While filter banks are essential components of speech processing, and in signal processing in general, they will have the focus in present days. An adaptive filter is a filter that self adjusts its transfer function according to its optimizing algorithms. Least mean square algorithm has slow convergence when used with nonstationary signals like speech and it has high computational cost but normalization of step size (or input signal) leads to a useful variant of the LMS algorithm known as the normalized LMS (NLMS) algorithm, which gives better convergence characteristics than the LMS because it uses a variable step - size with respect to the input signal power.To improve the convergence rate and/or computational complexity and also to overcome the disadvantage of a full band adaptive filtering, a structure is illustrated that is subband adaptive filtering; this will converge faster at a lower computational cost for speech and white noise inputs.This research shows most types of subband decomposition structures and makes comparison among them based on their performance to cancel the noise with minimum computational complexity, maximum convergence speed and maximum noise cancellation with lowest delay.Moreover three new hybrid tree configurations or the tree decom - position are proposed to maximize the overall performance of adaptive noisecancellation system.They are given the abbreviations HTPSAF1,HTPSAF2 and HTPSAF3. These three systems use polyphase filter bank that has showed a noticeable increase in the convergence speed and large reduction in the computational complexity due to the lower number of coefficients that can be achieved for the analysis/synthesis filters, which in turn will result in minimum delay in the reconstructed output speech signal.The algorithm of subband decomposition structures has been described theoretically then modeled under MATLAB simulation program using built - in filters and real input signals.

تصميم وتنفيذ منظومة مقاييس متوزعة ذكية == Design And Implementation of A Smart Distributed Metering System

اسم المؤلف: مهند غازي خميس
اسم المشرف: عدي عبد اللطيف عبد الرضا
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: This work is concerned with designing and implementing a smart energy metering system that consists of two smart energy meters and a billing center. The designed smart energy meter is a single phase meter in which the amount of consumed energy is calculated using PIC18F45K22 (which is a Peripheral Interface Controller (PIC)) and utilizing ACS758 (which is a Hall - effect based liner current sensor Integrated Circuit (IC)).The amount of consumed energy is sent to the billing center (which is implemented by using a laptop) for issuing the bills. The billing center receives the consumption data and sends the switching commands by utilizing an external communication technology. After comparing various communication technologies, ZigBee is chosen for this work.Two smart energy meters are implemented to test various communication conditions, such as multi - hopping. The design of the two smart energy meters differ only in the ZigBee addresses in the network.The program for the PIC's in the smart meters is written with MikroC PRO V6.0.1, while the program for the laptop in the billing center is written with Visual BASIC 6.

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

اسم المؤلف: شيماء شكري عبد الحليم
اسم المشرف: رشيد حميد الربيعي
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الكهرباء - قدرة ومكائن
الدرجة: ماجستير
الجامعة: الجامعة التكنولوجية - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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.

التشوه بالتوافقيات في اشارات التدفق للمتحسس السعوي الحيزي المثبت خارجيا == Harmonic Distortion In The Flow Signals of Externally Mounted Capacitive Spatial Filter

اسم المؤلف: مروه مالك حسوني
اسم المشرف: عباس احمد الشالجي
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية الهندسة - قسم الهندسة الالكترونية والاتصالات
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: This thesis investigates the performance of some windows on the flow signals that are generated from the planar capacitance spatial filter (PCSF) according to the moving of the solid particle in the channel of the filter. The sensor that operates as non - invasive device for solid flow measurement utilizes the thin wall of a dielectric pipe section as a shielding layer to protect the sensor from erosion, rust and moisture, and to make it more versatile.The finite - difference model equations are solved using successive over relaxation (SOR) methods. The waveforms show that the response of the PCSF is spatially - biased towards particle flowing closer to the plane of sensing electrodes and that the resulting flow signal is non - sinusoidal. The SOR method that is used to compute the PCSF potential fields has been investigated using a mesh of 110 by 32 nodes, and the algorithm was programmed in MATLAB (Release 2013a) using an Intel core ™ i3 PC,CPU processor.To study the effect of the total harmonic distortion (THD) content on the flow signals that are calculated with respect to the fundamental frequency of the power spectrum density through a specific quantitative criterion, this work comprises a comparative study among three types of windows; Hanning, Hamming, and a subOptimal window called the Kaiser window.The effect of particle flying heights, relative permittivity and size on the THD of the flow signal were examined. It was found that theTHD of flow signals at heights closer to the plane of sensing electrodes is high and decreasing gradualy when the particle flying height is far above the sensor. All the three windows used in this work have better suppression of harmonics distortion as compared with unwindowed (raw) flow signal.

تمثيل وتنفيذ العاكس ثلاثي الطور رباعي السيقان بواسطة طريقة المتجه الفضائي بتضمين عرض النبضة == Modeling And Implementation of Space Vector PWM Four - Leg Three Phase Inverter

اسم المؤلف: لؤي كمال عبد القادر
اسم المشرف: فاضل عباس مهدي القرملي
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الكهرباء
الدرجة: ماجستير
الجامعة: جامعة بغداد - كلية الهندسة - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: The thesis considers a three - phase four - leg inverter, which is used to supply unequal loads without using a transformer. In the literatures, a three - dimensional modulation technique, requiring complex mathematical algorithms were proposed for this kind of inverter. In this research a different approaches are discussed through two kinds of controller; first type is based on the separation control method of the fourth - leg of the inverter from the other phases for one type for modulation. This research applied to the three - phase inverter of the traditional SVM techniques avoiding the employment of complex procedures. The voltage modulation method based on a triangular carrier waveform for the three - phase four - leg voltage source converter. The four - leg converter can produce three - phase output voltages independently from the additional forth - leg. The proposed modulation method for the four - leg inverter is implemented with a single carrier by a simple useful “offset voltage” concept. The second type is equivalent to the so - called three - dimensional space vector PWM method, but its implementation is much easier. The simultaneously synthesized equations of the maximum magnitude of unbalanced three - phase voltage.The feasibility of the proposed modulation technique types verified by computer simulation and experimental results. These results show that both types of “Carrier - Based Pulse Width Modulation (PWM) technique” and “Three Dimensional Space Vector Modulation Technique” are easier implemented than conventional type by using microcontroller component (PIC16F874A/877A) instead of digital components (DSP & FPGA). So this thesis offers a prototype for this circuit with low cost and low harmonics, but with more complex control circuit.

تحليل المسار النازل لنظام الاتصال اللاسلكي التكيفي المتعدد المداخل والمخارج والمستخدمين == Analysis of Adaptive Downlink Multiuser Mimo Wireless Communication System

اسم المؤلف: عمر جبار ابراهیم
اسم المشرف: رعد سامي فياض
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الاتصالات
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية الهندسة - قسم الهندسة الالكترونية والاتصالات
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Multiple - input multiple - output (MIMO) wireless communication systems have received significant attention due to their enormous channel capacity potential in rich scattering environment. Such systems need to consider multiuser transmission / reception in their design. This thesis investigates theoretically the ergodic capacity of multiuser MIMO systems operating with adaptive techniques to enhance their performance. The ergodic capacity of multiuser MIMO system is analyzed and simulated for three types of channels : additive white Gaussian noise (AWGN) channel, uncorrelated Rayleigh fading (URF) channel, and semicorrelated Rayleigh fading (SRF) channel. The downlink SRF channel for each user is modeled by assuming that the fading is correlated at the transmitter but uncorrelated at the receiver side. The simulation results are compared to those related to a single - user system and used as a guideline to present an adaptivetechnique to enhance the capacity of MIMO system operating in SRF channel. The adaptive technique is based on a tradeoff between time division multiple access (TDMA) and block diagonalization (BD).Simulation results are presented using MATLAB environment to address the dependence of ergodic capacity of a MIMO communication on various system and channel parameters. The results indicate clearly that the threshold level of angle between users ? employed in the adaptive system must be chosen carefully to maximize the ergodic capacity. The optimum threshold ?th is equal to 24°, 42° and 47°, for angle spread ? = 5°, 50° and 75°, respectively

طرائق الكشف للتضمين الترددي المتعامد للرابط النازل في نظام تطور طويل الامد (LTE) == Detection Methods For Ofdm Downlink In Long Term Evolution (LTE) System

اسم المؤلف: اكرم جبار عبد الحسين حسن
اسم المشرف: يمان اسماعيل مجيد
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
الجامعة: جامعة بغداد
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: GPP3 التطور على المدى الطويل (LTE) هو تقنية الجيل الرابع اللاسلكية ذات النطاق العريض. هدفه الرئيسي هو تعزيز الكفاءة الطيفية باستخدام تقنيات التضمين الترددي المتعامد بالتقسيم (OFDM). ومع ذلك، ياتي هذا التحسن في الاداء بزيادة التعقيد الحسابي في اجهزة الاستق | 3GPP Long Term Evolution (LTE) is the fourth generation mobile wireless broadband technology. Its key objective is to enhanced spectral efficiency by using Orthogonal Frequency Division Multiplexing (OFDM) techniques. However, this performance improvement comes at the cost of increased computational complexity in the receiver. The goal of this work is to introduce a detection method that gives a better performance with reasonable computational complexity for LTE mobile communication system. An approximated linear baseband model for the two modulation techniques used by the LTE system (which is the Quadrature Phase Shift Keying (QPSK) and sixteen - level Amplitude Modulation (16 - QAM)) have been derived. Three receivers have been simulated and tested. The three receivers use Least Square (LS) channel estimator. These receivers uses channel compensator, decision feedback equalizer and perturbation algorithm. The LTE communication system has been simulated using MATLAB®7 programming language. The results of the computer simulation show that the perturbation algorithm gives an enhancement in the receiver performance of about 2 dB in different mobile channels than decision feedback equalizer and about 5 dB than channel compensator at the 10 - 3 of BER.

بناء خوارزمية تزامن لانظمة (OFDM) باستخدام معالجة الاشارة الرقمية == Dsp - Based Synchronization Algorithm Implementation For OFDM System

اسم المؤلف: رائد ستار جبر
اسم المشرف: محمود عبد القادر عبد الستار
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
الجامعة: جامعة بغداد - كلية الهندسة - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: تعدد الارسال للتردد بالتقسيم المتعامد (OFDM) هو مفتاح تمكين التكنولوجيا لمعظم انظمة الاتصالات اللاسلكية الحالية ذات معدل نقل البيانات العالي. والميزة الرئيسية للـ (OFDM) مقارنة بالطرق التقليدية هو انه يحول القناة ذات النطاق العريض الى قنوات فرعية ضيقة متو | Orthogonal Frequency Division Multiplexing (OFDM) is the key enabling technology for most current high data - rate wireless communication systems. The primary advantage of OFDM over conventional schemes is that it converts a wideband channel into parallel narrowband sub - channels allowing relatively simple channel estimation and frequency domain equalization. It is as an effective technique for coping with channel impairments like multipath propagation and Inter Symbol Interference (ISI) by making use of an appropriate cyclic prefix. One of the major drawbacks of OFDM is that it is more sensitive to synchronization errors than its single carrier counterparts. This thesis describes a real - time implementation of a timing and frequency synchronization for OFDM system using MATLAB software Simulink, DSP processor TMS320C6713 and Code Composer Studio (CCS). The hardware interface converts the baseband signal from the PC to the DSP Processor. Basic transmission and reception performances are evaluated in real time using Real Time data Transfer (RTDX). The practical results and performance evaluation of the synchronization algorithms in OFDM system is presented and discussed. The results are plotted for different offsets of CFO and STO with different values of signal to noise ratio. Also the bit error rate (BER) and the mean square error (MSE) of the system is analyzed. The results show that the time offset more effect than frequency offset because of ISI and ICI occurs when time offset occur in the system. The synchronization algorithm is found to be robust for both CFO and STO simultaneously. It can handle offset of about CFO = 500 Hz and STO = 14 samples simultaneously without wasting extra bandwidth. This algorithm used for synchronization more robust for 16QAM compared with 4QAM modulation.

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

اسم المؤلف: نور احمد سلمان
اسم المشرف: ثائرة زكريا الطيار
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك
الدرجة: ماجستير
الجامعة: الجامعة التكنولوجية - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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.

محاكاة GSM/EDGE وGSM لنظام الاتصالات المتنقلة == Simulation of GSM And GSM/EDGE Mobile Communication Systems

اسم المؤلف: اسامة علي عبد الله
اسم المشرف: رعد سامي فياض
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الاتصالات
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية الهندسة - قسم الهندسة الالكترونية والاتصالات
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: The introduction of global system for mobile communication (GSM) air interface has undoubtedly created a new area in telecommunications. In view of its extensive use in real world applications, it is highly desirable to further investigate the performance of the GSM system under different operating conditions and environments. Furthermore, there is increasing interest in using high - level modulation to provide enhanced data rate for GSM evolution (EDGE).This thesis investigates the performance of both GSM and GSM/EDGE systems operating in Raleigh fading channel. The results are reported for different models of fading channel in order to describe various environments. A detailed SIMULINK model is developed in MATLAB environment to simulate the GSM system. Furthermore, a MATLAB software package is developed to simulate extensively the EDGE system. Both simulation models are handled to characterize each essential part in these systems. The simulation takes into account channel coding, modulation type, interleaving and burst building, multipath channel effect, channel estimation, and detection process.The simulation results indicate clearly that to achieve a bit error rate (BER) of 1x10P - 5 P in additive white Gaussian noise (AWGN) channel, the signal - to - noise (SNR) ratio should be 5.25, 3.75 and 12.25 dB when GSM, MCS - 1 EDGE (GMSK modulation), and MCS - 7 EDGE (3?/8 - 8PSK modulation) systems are used , respectively. These values are to be compared with R12R.43, R1R0.21 and R2R1.05 dB, respectively, for HT100 - type fading channel. The MSC - 1 system offers the best BER characteristics followed by GSM system. The MCS - 7 offers the worst BER characteristics among the three systems.

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

اسم المؤلف: انس عبد الحميد كاظم
اسم المشرف: خالدة شعبان رجب
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك
الدرجة: ماجستير
الجامعة: الجامعة التكنولوجية - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: سيف حسام عبد الواحد
اسم المشرف: علي يوسف فتاح
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الاتصالات
الدرجة: ماجستير
الجامعة: الجامعة التكنولوجية - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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.

تاثير اللاخطية في الالياف البصرية على اداء نظام تجميع الاطوال الموجية الضوئية المنقسمة باستخدام تقنية الاستقطاب المزدوج لتقسيمات التردد المتعامد الضوئي == Effect of Fiber Nonlinearity On The Performance of WDM Optical Systems Using Dual Polarization CO - OFDM Technique

اسم المؤلف: بشار مظفر احمد
اسم المشرف: رعد سامي فياض
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية الهندسة - قسم الهندسة الالكترونية والاتصالات
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: The implemented existing high capacity optical networks are based on 50 GHz wavelength - division multiplexing (WDM) channel spacing and carry up to 50 Gb/s data rate per channel. In recent years, there is increasing interest in using dual - polarization (DP) technique to enable future systems with at least 100 Gb/s rate per channel to operate over existing optical networks. The performance of these advanced systems can be enhanced further by using coherent optical orthogonal frequency division multiplexing (CO - OFDM) technique which offers high spectral efficiency and outstanding tolerance of fiber dispersion.This thesis addresses the effect of fiber nonlinear optics on the performance of dual polarization CO - OFDM/WDM system operating with 100 Gb/s per channel. Different modulation formats, namely BPSK, QPSK and 16 - QAM, are used. First, the performance of a single - channel system is investigated in the absence and presence of fiber nonlinearity. The results are compared with those of a conventional (single - polarization) system to identify the key role played by the DP technique. The investigation is then extended to WDM systems incorporating DP - OFDM technique. The results reveal that the effect of fiber nonlinearity can be reduced or cancelled by using optimum transmitter laser power Popt. Further, the value of Popt is a function of transmission distance,number of multiplexed channels, and modulation formats. Popt of - 11, - 12, and - 5 dBm is needed for a ten - channel DP system operating with BPSK, QPSK, and 16 - QAM formats, respectively.Simulation results presented in this thesis are obtained using OptiSystem (version 11.1) which is a commercial software package.

الموقع الامثل للمعوض التزامني الثابث لشبكة الضغط الفائق العراقية باستخدام الخوارزمية الجينية == Optimal Location of Static Synchronous Compensator (STATCOM) For Iraqi National (400kV) Super High Voltage Grid Using Genetic Algorithm

اسم المؤلف: حسن علي عبد المجيد سلبي البياتي
اسم المشرف: Firas Mohammed Tuaimah
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الكهرباء
الدرجة: ماجستير
الجامعة: جامعة بغداد - كلية الهندسة - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Transmission networks of modern power systems are becoming increasingly stressed because of the growing demand and restrictions on constructions new lines. One of the consequences of such a stressed system is the threat of losing stability following adisturbance. Flexible AC Transmission System (FACTS) devices are found to be very effective in a transmission network for better utilization of its existing facilities without sacrificing the desired stability margin.The Static Synchronous Compensator (STATCOM) is a shunt device which employs one of the latest technologies of FACTS and power electronic switching devices in electric power transmission systems to control the voltage and power flow. The STATCOMregulates the voltage at its terminal by controlling the amount of reactive power injected into or absorbed from the power system.Whilst the Iraqi National (400 kV) Super High Voltage Grid System suffers from voltage stability problems because of the high variation in the reactive power conditions all over the year seasons. Therefore, this thesis proposed an application of the STATCOM devices to maintain the voltages within the specified limits and enhancing voltage stability for all seasons in the year, as well as reducing the apparent power losses. And in order to reduce therequired installation cost of the STATCOM devices, this performance has been done by using minimum possible size of the reactive power injected or absorbed by the STATCOM devices, while satisfying the stability limits.The benefit of the STATCOM devices depends greatly on how these devices can be placed in the system. The general problem focused in this thesis was how to optimally determine the locations and the sizes of the STATCOM devices that to be installed. For thatreason, it was decided to follow an optimization approach such as a Genetic Algorithm (GA), which is one of the heuristic methods to find the optimum location and the value of installed STATCOM devices.The Newton - Raphson load flow method, with the proposed approach has been examined and tested first on the 5 - bus IEEE test system; the results obtained encouraged us to implement the same approach on the 27 - bus Iraqi National (400kV) SHV Grid System.The real data for Iraqi network have been taken from Iraqi National Control Center (INCC), in the Ministry of Electricity.computer program, written in MatLab environment, was developed to represent the proposed method.

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

اسم المؤلف: مروة جليل محسن
اسم المشرف: اثير علاء صبري
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الاتصالات
الدرجة: ماجستير
الجامعة: الجامعة التكنولوجية - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: هاجر احمد ابراهيم
اسم المشرف: اثير علاء صبري
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الاتصالات
الدرجة: ماجستير
الجامعة: الجامعة التكنولوجية - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: انسام صبحي جبار
اسم المشرف: محمد مؤنس عز الدين
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الكهرباء - قدرة ومكائن
الدرجة: ماجستير
الجامعة: الجامعة التكنولوجية - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: سهاد حسين جاسم
اسم المشرف: احمد سعدون عز الدين
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك
الدرجة: ماجستير
الجامعة: الجامعة التكنولوجية - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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

اسم المؤلف: ياسر محمد عبد
اسم المشرف: حنان عبد الرضا عكار
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك
الدرجة: ماجستير
الجامعة: الجامعة التكنولوجية - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: 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.

الغاء تداخل المسا ارت التخميني في انظمة الوصول المتعدد باستخدام تقسيم الترميز الواسع الطيف لشبكات الاتصال اللاسلكية == Multipath Interference Cancellation Investigation In Wcdma Communication Networks

اسم المؤلف: نور محمد خليل
اسم المشرف: منال جميل الكندي
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية الهندسة - قسم الهندسة الالكترونية والاتصالات
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Bit Error Rate (BER) and Bit Energy to Noise Ratio(?????????) performance of the 1 - D RAKE receiver without , with Space Time Transmit Diversity (STTD) and 2 - D RAKE without , with (STTD) and also without and with beamforming for WCDMA over RayleighChannel in presence of Additive White Gaussian Noise (AWGN) channel is demonstrated with purpose of making simulation of m - files developed in Matlab.Results are evaluated in terms of BER and ????????? considering the number of Base Station (BS) transmit antennas (1 - D RAKE and 2 - D RAKE receivers), and the number of RAKE fingers (1 - D RAKE receiver) and the number of Mobile Station (MS) receive antennas (2 - DRAKE receiver). The performance results of 1 - D RAKE and 2 - D RAKE receivers showed that the receivers have satisfactory BER performance and the performance of RAKE receivers is more improved by increasing the number of RAKE fingers, performance is even better when beamforming was applied.The performance results of the three receive diversity of 2 - D RAKE receiver schemes : Selection Combining (SC), Equal Gain Combining (EGC) or Maximal Ratio Combining (MRC)) of 2 - D RAKE showed that there are significant improvements in BER and ?????????performance over the 1 - D RAKE. BER of 10???? can be obtained at ????????? ? 5 dB performance with four fingers of 2 - D RAKE receiver with STTD and beamforming and MRC scheme for five receive antenna elements.

تحسين جودة الصورة التوموغرافية المعاد تركيبها باستخدام خوارزمية التسقيط العكسي المرشحة == Enhancement of Tomographic Image Quality Reconstructed By Filter Backprojection Technique

اسم المؤلف: دعاء نوفل حازم
اسم المشرف: محمد حسين الحياني
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الالكترونيك والاتصالات
الدرجة: ماجستير
الجامعة: جامعة النهرين - كلية الهندسة - قسم الهندسة الالكترونية والاتصالات
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Computed tomography refers to the imaging of slices of an object by exposing them to X - ray in different directions. Measurement of image quality is one of great importance in the field of medical applications. In applications such as CT and MRI scanning, most of the time the quality of reconstructed image is assessed qualitatively by radiologist or domain experts which are purely subjective evaluation.The FBP algorithm produces excellent quality and high performance reconstruction compared with other reconstruction algorithms. This thesis presents different projection types (fan beam geometry, and cone beam geometry) for the image reconstruction, the geometries are calculated analytically by specified 2D head phantom for fan beam and 3D head phantom for single slice spiral cone beam geometry with different ranges covering angle.In the thesis the FBP algorithm was applied with the fan beam and single slice geometries. Different types of filters (Hann, Hamming, Kaiser, Cosine, Ram - Lak, and Gaussian) are used in the algorithm and a new window filter is proposed in the algorithm. Comparisons are made between the new window and different common windows by quality measurement to get a reconstructed image with high quality and high performance suitable for the implementation of the FBP.A computer programs has been designed, written, and implemented in this work using MATLAB 7.1, for fan beam and single slice projections. Good results of quality and performance were obtained for the tomographic reconstructed image from its projection on CT scanner.

تقنيات النمذجة الذكية في تنبوء حمل الطاقة الكهربائية == Intelligent Modeling Techniques of Electric Power Load Forecasting

اسم المؤلف: يونس محي نصيف
اسم المشرف: حنان ميخائيل داود
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الكهرباء
الدرجة: ماجستير
الجامعة: جامعة بغداد - كلية الهندسة - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: As far as electrical power system is concerned, there has been a need to find out the future load in advance. Load forecasting has played an important role in the generation, transmission and distribution system planning. Load forecasting of future load demand is significant for an economic and secured operation of power systems. In general, the objective of high - precision load forecasting is difficult to achieve due to complex effects on load by a variety of factors.This thesis focuses on the study of long term load forecasting by using multiple linear regression (MLR) method and using different types of computational intelligence methods such as feed forward Neural Network with back - propagation (BP) tuning algorithm (FNN - BP), feed forward Neural Network with particle swarm optimization (PSO) tuning algorithm (FNN - PSO) and Elman Neural Network with back - propagation (BP) tuning algorithm (ENN - BP). Such forecasts will be highly useful in proper system planning and operations. The algorithms have been demonstrated using simulation programs in MATLAB environment.The usefulness of the five forecasting techniques was tested on a test system data for a Big Utility Company (Egyptian Unified Network). The obtained results showed that the ENN - PSO method takes advantage of accuracy and efficiency in prediction.The ENN - PSO method was performed using population growth data on the Iraqi National Grid for the duration from 2014 to 2030.

النظام المضبب للتحكم بمشكلة التزاحم لبروتوكول (التحكم في الارسال) في الشبكات المختلطة == A Fuzzy Based TCP Congestion Control For Hybrid Networks

اسم المؤلف: سارة رعد قاسم
اسم المشرف: زينب توفيق باقر
الموضوع العام: هندسة الكهرباء والالكترون والاتصالات
السنة: 2014
الموضوع الدقيق: هندسة الكهرباء
الدرجة: ماجستير
الجامعة: جامعة بغداد - كلية الهندسة - قسم الهندسة الكهربائية
اللغة: الانكليزية
مكان الجامعة: بغداد
الصفحات الاولى:
المستخلص: Transmission Control Protocol (TCP) is designed to deliver seamless and reliable end - to - end data transfer across unreliable networks and is offered connection - oriented, byte - stream service. The Internet’s TCP is probably the most widely used protocol; it is also the most carefully tuned since performance of Internet is largely based on TCP. However, throughput in TCP degrades notably when operated in erroneous networks. In erroneous networks, TCP misinterprets random packet losses and the subsequent packet reordering due to high bit error rate as congestion and invokes congestion control by triggering to fast retransmission and fast recovery, leading to under - utilization of the network resources and affecting TCP performance critically.Many proposals have been used to improve TCP performance in wireless networks. Most of these proposals were based on changing the TCP header and add more complications to the main mechanism. Means of improving performance of TCP over erroneous links were proposed using fuzzy controller in a simple manner (without changing the header) by tracking the delay and the frequencies of the occurrences of timeouts and triple duplicate acknowledgement (3dupacks) to differentiate congestion loss from bit error loss. The first proposal was FReno (Fuzzy+NewReno) but this new algorithm failed to achieve good efficiency. The second proposal was FVegas (Fuzzy+Vegas) and it also failed to improve TCP’s resource utilization. The third proposal was FWestwood (Fuzzy+Westwood) which significantly improved TCP performance. The proposed algorithm was compared against standard TCP variants for different error rates using OMNET++4 version 4.3.1 IDE simulator. FWestwood algorithm helped TCP to distinguish between congestion and packet loss and increase the performance in erroneous wired network, heterogeneous networks, wireless networks and mobile network. Results from simulations showed that in a congested network with (1% to 10%) of random packet loss rate, FWestwood achieved significant improvements in different erroneous networks over other TCP schemes. Also it achieved friendliness fair share of the link with other TCP standards.
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