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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.
👁 مشاهدة
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.
👁 مشاهدة
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.
👁 مشاهدة
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.
👁 مشاهدة
المسار الامثل للجراحة الروبوتية الطبية باستخدام الخوارزمية الجينية == Path Optimization For Medical Surgery Robotic Using Genetic Algorithm
اسم المؤلف:
زهراء داود حسين
اسم المشرف:
مهند زيدان خليفة | ايمان صالح كريم
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2014
الموضوع الدقيق:
الهندسة الكهروميكانيكية
الدرجة:
ماجستير
الجامعة:
الجامعة التكنولوجية
اللغة:
الانكليزية
مكان الجامعة:
بغداد
الصفحات الاولى:
المستخلص:
تناولت هذه الرسالة دراسة تصميم امثل لموديل مختار للانسان الالي المستخدم في مجال الجراحة البشرية (جهاز التنظير البطني الجراحي ) المستخدم في مستشفى الصدر التعليمي في محافظة ميسان والمصنع من قبل شركة (KARL STORZ) من خلال زيادة عدد درجات الحرية لتصل سبعة درج | This thesis presents a study for optimal design of a robot to be used in human surgery (Laparoscope device). It was done in Al - Sader educational hospital in Maysan Governorate. The robot was manufactured by Karl Storz company. Connecting linkages were increased to get seven degrees of freedom. It is operated by the surgeon hand (complete rotation 360o , rotation in two opposite directions perpendicular to each other ,transformation along the major axes , triple joint (pitch ,roll, and yaw). Optimization has been done to these models after making analysis to the surgical robot (forward kinematic, inverse kinematic, dynamitic analysis). The optimal design was obtained by using genetic algorithm method to choose the optimal path planning in the working area. This was with the presence of obstacles to tip of end - effector motion that exists, in mechanical arm to the new model that used in this thesis. This was done by making an integrated computer program through MATLAB (R2013a). The results of best path planning would shorten length without hitting any obstacle, assuming the surrounding environment will be variable. The position and obstacle shapes would be random. We found that the best path planning in every environment depends on maximize objective function that presented by shortest length of the path. This is important from the medical point of view. This was applied successfully in practice on an industrial robot and the resulted optimal parameters to that robot with matching of the theoretical side with practical side in robot motion. The practical side was made in laboratory of the Research Unit of Automation and Robotics in the Control and Systems Engineering Department, University of Technology. The robot used was the Lab - Volt Servo Robot System Model 5250 (RoboCIM5250). This thesis includes studying the tools used in laparoscope and focuses on recent types of graspers with parallel jaws connected to the chosen design. It was noticed that the maximum entrance force for the abdominal tracar must not exceed 5N. The force on the last point of jaws is 0.42N. It was found that this force will not cause bleeding in the tissue during procedure. And that this type of small size grasper can be bent during operation in the allowed field of workspace while maintaining good strength.
👁 مشاهدة
التوزيع الامثل للمتحسسات في شبكة المتحسسات اللاسلكية باستخدام خوارزمية الامثلية المستوحاة من نظرية الاسراب == Optimum Sensors Deployment In Wireless Sensor Networks Using Swarm Based Bio - Inspired Optimization Algorithms
اسم المؤلف:
هيثم سعدون عفتان
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:
The increased demand for Wireless Sensor Networks (WSNs) in different areas of application has intensified studies dedicated to the deployment of sensor nodes in the recent past. The deployment of sensor nodes required that some of the key objectives should be satisfied, which are the coverage ratio of the monitoring area and the lifetime of the network.In this thesis, a mathematical model to optimize the coverage ratio and the lifetime of network is developed to ensure a better utility of the WSN. The model is formulated based on several parameters such as the size of the monitoring area, network models, the total number of sensor nodes, visibility requirements, sensing/communication radius, etc.Popular swarm based bio inspired algorithms have been used to optimize the WSN deployment. The coverage optimization process has been carried out by single objective optimization algorithms such as the Ant Colony Optimization (ACO) algorithm, modified version of Particle Swarm Optimization called Discrete PSO (DPSO), Discrete Artificial Bee Colony (DABC) algorithm and a new proposed algorithm called Quantum Artificial Bee Colony (QABC). QABC is based on quantum physical concepts to improve the local search capability of standard ABC algorithm. Thereafter, a multi objective optimization algorithm has been utilized to optimize the coverage ratio and lifetime of WSN. The multi objective optimization has been carried out by Non - dominated Sorting Genetic Algorithm (NSGA - II). All of these algorithms are simple, effective and computationally efficient optimization techniques.The WSN deployment has been simulated using MATLAB 7.12.0 (R2011a) package, NetBeans 7.4 Java integrated development environments, JMETAL 4.5 and Java Universal Network/Graph (JUNG 2.0.1) frameworks. The computer simulation results showed that the proposed algorithm for coverage ratio maximization was up to two times faster than the others. Furthermore, the conducted simulation indicated that the QABC algorithm offered (6%) better solution in terms of coverage in comparison with the others in some cases. Also the results showed that the deterministic deployment can achieve up to (25%) better coverage ratio than the random deployment. In addition, QABC outperformed GA, PSO and ABC algorithms when applied to several test problems. Additionally, the results showed that the NSGA - II algorithm could effectively optimize the network lifetime and coverage ratio and produced good convergent solutions to the Pareto front and was uniformly distributed along it.
👁 مشاهدة
نظام كشف وتمييز لوحة الرخصة للسيارات العراقية == License Plate Detection And Recognition System For Iraqi Cars
اسم المؤلف:
ثائر عذار هاشم
اسم المشرف:
اياد ابراهيم عباس
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:
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%.
👁 مشاهدة
محاكاة تضمين تقسيم التردد المتعامد المتعدد المستخدمين المشفر في الخط النازل == Simulation of Coded Multiuser Ofdm Downlink
اسم المؤلف:
دﻧﻴﺎ ﻓﺆاد فاروق النعيمي
اسم المشرف:
رعد سامي فياض
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2008
الموضوع الدقيق:
هندسة الاتصالات
الدرجة:
ماجستير
الجامعة:
جامعة النهرين - كلية الهندسة - قسم الهندسة الالكترونية والاتصالات
اللغة:
الانكليزية
مكان الجامعة:
بغداد
الصفحات الاولى:
المستخلص:
The orthogonal frequency division multiple access (OFDMA) scheme adopts orthogonal frequency division multiplexing (OFDM) subcarriers, which are particularly suited for transmition over broadband frequency selection channels, to support multiusers. The scheme considered usually assigns a subset of subcarriers to each user and adopted adaptive techniques for the allocation of available resources/subcarriers according to the channel state information (CSI) estimated at the transmitter using a reverse link. This thesis proposed three coded multiuser OFDM schemes based on spreading the data of each user over all subcarriers without CSI at the transmitter. The idea behind these schemes is to split the OFDM transceiver into two stages : one common to all users while the other consists of identical parallel units with each unit is used to process the data related to an individual user. The two stages are separated by a multiplexer/demultiplexer unit whose position can be chosen to yield different schemes. The three schemes considered here are : user multiplexed scheme, inner coded multiplexing scheme, and mapper multiplexing scheme. The proposed schemes implemented are using MATLAB simulink (version 7) to investigate their performance under different operating conditions related to number of users, Rayleigh fading channel, and serial concatenated codes. The results are compared with those related to two conventional schemes, subcarrier mapping scheme and outer coded multiplexing scheme. The simulation results indicate that the proposed user multiplexing scheme may offer performance as high as that offered by the conventional outer coded multiplexing scheme but with reduced number of equipments.
👁 مشاهدة
تهيئة حاسوبية لموجه سيسكو == Computer Based Configuration For Cisco Routers
اسم المؤلف:
فارتان رافي كريكوريان
اسم المشرف:
غسان حميد عبد المجيد
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2008
الموضوع الدقيق:
هندسة الاتصالات
الدرجة:
ماجستير
الجامعة:
جامعة النهرين - كلية الهندسة - قسم الهندسة الالكترونية والاتصالات
اللغة:
الانكليزية
مكان الجامعة:
بغداد
الصفحات الاولى:
المستخلص:
Routers are intelligent devices that make connection between different networks possible. In addition, routers can perform several functions, including filtration and selection of the best path of packets movement. Routers must be configured efficiently in order to perform the above functions. In literature, two approaches have been distinguished for the configuration, namely; text mode and graphical mode approach. The present work is analyzing these two approaches and defines precisely their advantages and limitations. As a result of this analysis, a new approach is proposed in this thesis which eliminates the limitations. The work proposes a graphical interface which is executed on a desktop (or laptop) PC. The user defines the configuration parameters through a program which transfers these parameters to the router by console port instead of Ethernet port. These parameters are then saved on Non Volatile Random Access Memory. The proposed graphical interface is implemented by standard lab consisted of two routers. The implementation shows that the time of configuration can be reduced to 70% of the text mode approach, and overcome the trouble of the old graphical interface.
👁 مشاهدة
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
اسم المؤلف:
مصطفى عبد الهادي جليل
اسم المشرف:
عايد خلف محمد
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
الكلمات الدلالية:
Radio - over - Fiber (RoF)
Quadrature Phase Shift Keying (QPSK)
Quadrature Amplitude Modulation (QAM)
Orthogonal Frequency Division Multiplexing (OFDM)
Digital Signal Processing (DSP) Unit
الصفحات الاولى:
المستخلص:
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.
👁 مشاهدة
تحسين الاستقرارية باستخدام التوليد الموزع في شبكة النجف الاشرف الكهربائية == Stability Enhancement Using Distributed Generation In Al - Najaf Al - Ashraf Electrical Network
اسم المؤلف:
زيد طارق حسن
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:
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.
👁 مشاهدة
تصميم وتصنيع والتحقق من الخلية الشمسية ذات الصبغة الحساسة للضوء == Design, Fabrication And Verification of Dye Sensitized Solar Cell DSSC
اسم المؤلف:
صابرين سمير حسان
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
الكلمات الدلالية:
Dye sensitized solar cells
natural dyes
synthetic dye
الصفحات الاولى:
المستخلص:
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%.
👁 مشاهدة
تقليل تموج عزم الدوران في طريقة السيطرة المباشرة لعزم الدوران للمحركات الحثية == Torque Ripple Reduction Based Direct Torque Control For Induction Motor Drives
اسم المؤلف:
حيدر سالم حميد
اسم المشرف:
Prof. Dr. J.H. Alwash | Hanan M. Habbi
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:
التحكم المباشر لعزم الدوران هو اسلوب التحكم المستخدم في انظمة محرك التيار المتناوب للحصول على سيطرة عزم دوران عالية الاداء. محرك DTC التقليدية يحتوي على زوج من الـ ( hysteresis comparators)، حساب الفيض وعزم الدوران وجدول اختيارالـ ( voltage vector). يت | Direct Torque Control (DTC) is a control technique used in AC drive systems to obtain high performance torque control. The conventional DTC drive contains a pair of hysteresis comparators, a flux and torque estimator and a voltage vector selection table. The torque and flux are controlled simultaneously by applying suitable voltage vectors, and by limiting these quantities within their hysteresis bands, de - coupled control of torque and flux can be achieved. Conventional DTC drives utilizing hysteresis comparators suffer from high torque ripple and variable switching frequency. Several techniques have been developed to improve the torque performance. In this thesis, Proportional - Integral (PI) controller has been presented to improve the system performance which gives better torque and flux response and also reduces the undesirable torque ripple. The most common solution to high torque ripple and variable switching frequency is to use the space vector pulse width modulation (SV - PWM) that depends on the reference torque and flux. The reference voltage vector is then realized by using a voltage vector modulator.The conventional DTC and DTC with PI controller are implemented using Xilinx System Generator (XSG) for MATLAB/Simulink environment through Xilinx blocksets. The design was achieved in VHDL, based on a MATLAB/Simulink simulation model. The Hardware - in - the - Loop (HIL) method is used to verify the functionality of the Xilinx FPGA estimator. The results are obtained and compared with MATLAB/ Simulink results considering the implementation of the proposed model on the Xilinx NEXYS2 Spartan 3E1200 FG320 Kit. The simulations of the DTC - SVPWM were carried out using MATLAB/ Simulink simulation package. The design, implementation and simulation of the overall drive system is performed using MATLAB/Simulink program version 7.13.0.564 (R2011ba) and Xilinx ISE Design Suite 14.2.
👁 مشاهدة
تمييز قزحية العين باستخدام التحويل الموجي والشبكات الاصطناعية
اسم المؤلف:
احمد عز الدين عبد الله
اسم المشرف:
هديل نصرت عبد الله
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:
التعرف على قزحية العين هي تقنية القياس الحيوي التي تتناول تحديد الهوية على اساس قزحية الانسان. يعتبر تميز القزحية من انواع التكنولوجيا الحيوية الاكثر دقة المتاحة اليوم بالمقارنة مع انواع كثيرة من التقنيات البيومترية المستخدمة مثل : مسح بصمات الاصابع، التعر | Iris Recognition is a Biometric Technology which deals with identification based on the human iris. It is considered to be the most accurate biometric technology available today compared with many kinds of biometric technologies used, like Fingerprint scanning, Face recognition, Voice recognition and Hand geometry scanning because it has some advantages, such as uniqueness, stability and high recognition rate etc., makes iris recognition so accurate.In this proposed system, two database systems are used. The first is CASIA database system (version 1.0)(Chinese Academy of Sciences Institute of Automation). And, the second is Real database system by using real persons (each with many images) for recognition through camera Mobile Type of Galaxy Note3. An approach to get more accuracy of the offline iris recognition is composed of many steps : capturing the iris image, determining the location of the iris boundaries, normalization, preprocessed using median filter to remove noise, using wavelet transform for two types of filter, Haar and Daubechies, in order to extract the features and finally using the matching by artificial feed forward neural network with back propagation algorithm (FFBNN) for training and testing iris image.In CASIA system, the iris recognition rate for Haar filter was 84.2% and for Daubechies filter was 92.8%, while in the real system, iris recognition rate for Haar filter was 90% and for Daubechies filter was 98.7%. This means the Daubechies filter is the best in execution time and mean square error from the Haar filter. Finally, efficiency of this system is logical, because the performance measurement of False Acceptance Rates was reasonable. The results and the experiments were implemented by P4 computer and the software package MATLAB (R2011a).
👁 مشاهدة
تطبيق الشبكة العصبية في تكوين الشعاع المتكيف لنظام الهوائي الذكي == Neural Network Application In Adaptive Beamforming For Smart Antenna System
اسم المؤلف:
سليمان احمد غازي
اسم المشرف:
عضيد حسن سلومي
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2015
الموضوع الدقيق:
هندسة الكهرباء
الدرجة:
ماجستير
الجامعة:
الجامعة المستنصرية - كلية الهندسة - قسم الهندسة الكهربائية
اللغة:
الانكليزية
مكان الجامعة:
بغداد
الصفحات الاولى:
المستخلص:
انظمة الهوائيات الذكية تعمل على تحسين الاداء وزيادة في السعة لانظمة الاتصالات المتنقلة. ويمكن لانظمة الهوائيات الذكية حل مشكلة نظام الاتصالات المتنقلة مثل التدخل في نفس القناة، والتاخير الحاصل نتيجة الانتشار والمسارات المتعددة التي تاخذها الاشارة عن طريق | The smart antenna systems are promise to provide performance improvement and capacity increasing for the base station of mobile communication systems. Smart antenna systems can solve the problem of mobile communication system such as co - channel interference , delay spread and multipath by an advance signal processing technology called beamforming. In this work artificial neural networks (Feed Forward Neural Network (FFNN) and feedback Elman Recurrent Neural Network (ERNN) ) are used for smart antenna adaptive beamforming for one and multiple targets.Neural network is used to calculate the optimum weights of antenna array to adapt the radiation pattern of the antenna array by directing multiple narrow beams toward the desired users and nulling interference or unwanted users. FFNN and ERNN are trained by supervised backpropagation learning algorithms, FFNN was trained by using Levenberg - Marquardt (lm),Resilient Back - Propagation (Rprop), Gradient descent with momentum and adaptive learning rate (gdx), Gradient descent and adaptive learning rate (gda) and biasing regulation(br), while lm and Rprop are used to train ERNN..The simulation results show that the best performance of smart antenna adaptive beamforming for one and multiple targets is obtained when the NN (FFNN and ERNN) trained by lm algorithm as compared with other algorithms, since it consider the fastest supervised training algorithm but with more memory requirement. Where the performance of FFNN training phase based (lm) algorithm for single target for five element uniform linear array antenna is [2.746641e - 14] at epoch 27 with best validation performance and best test performance approximately equal to the best training performance. While The performance of ERNN training phase based lm algorithm for single target is [1.121938e - 14] at epoch 38 with best validation performance equal to [1.682442e - 14] and the best test performance is [3.363946e - 14].The neural network model in adaptive beamforming are compared with smart antenna adaptive beamforming based on Least Mean Square (LMS) algorithm, and gave better performance than LMS.
👁 مشاهدة
تقييم اداء نظام تحويل المويجات المنفصلة - مازج تقسيمات التردد المتعامد المشفر للتطبيقات ذات السرعة العالية == Performance Evaluation of DWT - COFDM System For High Speed Applications
اسم المؤلف:
ضفاف طلال شاكر
اسم المشرف:
سعد سفاح حسون
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2014
الموضوع الدقيق:
هندسة الكهرباء
الدرجة:
ماجستير
الجامعة:
جامعة بابل - كلية الهندسة - قسم الهندسة الكهربائية
اللغة:
الانكليزية
مكان الجامعة:
بابل
الصفحات الاولى:
المستخلص:
The internet revolution has created the need for wireless technologies that can deliver data at high speeds in a spectrally efficient manner. However, supporting such high data rates with sufficient robustness to radio channel impairments requires careful selection of modulation techniques. The demand for high - speed mobile wireless communications is rapidly growing. OFDM technology promises to be a key technique for achieving the high data capacity and spectral efficiency requirements for wireless communication systems. Abstract In this thesis, Inverse Discrete Wavelet Transform (IDWT) is used as a modulation technique instead of Inverse Fast Fourier Transform (IFFT) with coded OFDM due to its excellent orthogonality and superior spectral containment properties of wavelet filters. Coded Orthogonal Frequency Division Multiplexing (COFDM) is the same as OFDM except that forward error correction is applied to the signal before transmission. This is to minimize errors in the transmission due to lost carriers from frequency selective fading, channel noise and other propagation effects. Convolutional code is used in this thesis as a forward error correction code. The proposed (DWT - COFDM) system is simulated under the effect of additive white Gaussian noise channel, and multi - path fading channel at different values of Doppler frequencies (22.2Hz, 41.7Hz and 444.4Hz) which are the most significant impact channel parameters on the bit error rate performance. The proposed system is also compared with DWT - OFDM, FFTCOFDM and FFT - OFDM systems. It is found that the proposed system can significantly improve the BER performance and it performs better than the other three systems. On the other hand, convolutional code and DWT is used to reduce the peak to average power ratio (PAPR) which is considered the serious problem in any wireless communication system using multi carrier modulation techniques like OFDM systems by using two of the most important non distortion techniques which are selective level mapping (SLM) and partial transmit sequence (PTS) and the results show that the proposed systems for SLM and PTS techniques can perform better than the conventional SLM and PTS. The results also show that the proposed PTS technique performs better than the proposed SLM technique.
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اكتشاف العطل الارضي المنفرد واخماده ذاتيا باستخدام السيطرة على ملف بترسون في شبكة التوزيع == Detection of Earth Fault And Self - Extinguishing By Controlling Petersen - Coil In Distribution Grid
اسم المؤلف:
فريال ابراهيم الظفيري
اسم المشرف:
عبد الغني عبد الرزاق عبد الطائي | قاسم كرم عبد الله
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2015
الموضوع الدقيق:
هندسة الكهرباء - قدرة ومكائن
الدرجة:
ماجستير
الجامعة:
جامعة بابل - كلية الهندسة - قسم الهندسة الكهربائية
اللغة:
الانكليزية
مكان الجامعة:
بابل
الصفحات الاولى:
المستخلص:
ان اكثر الاعطال شيوعا والتي تتعرض لها الشبكة الكهربائية في العالم هو Single Line to Earth حيث ان عطل احدى الاطوار مع الارضي في الشبكات الكهربائية, يسبب هذا قوسا كهربائيا اضافه الى جهد كبير , اكبر من جهد الطورين مع بعضهما مما يزيد خطورة الفصل والعزل في ال | All over the world, the most common faults in the distribution network is the single line to ground fault. A single phase fault with the earthing in the distribution networks causes electrical arc as well as high voltage than the two phases together which increase the danger of separation and isolation in networks. Consequently, this case can be controlled through Peterson Coil which turns off or reduces the electrical arc that makes the network safer. This work has using technique to detect the earth fault in the single - phase by distinguishing between the higher and the lower values of the currents. Also, this technique is used to detect the capacity of earthing network lines and the possibility to adapt the capacitor for inductance in order to detect the electrical arc during faults and to detect the earth leakage.Moreover, we have used many methods to control Peterson coils such as using PID Controller , Fuzzy Logic Controller, Hybrid control PID and Fuzzy System and Adaptive Neural Fuzzy Inference system, to determine the earth fault current at values equal to the current in the two sound phases. To getting best results for the fault current through conducting lab experiences by using DC Servo motor and Arduino. And the fault current is converted from the rated current, thus thousands of tons of copper cost are save. They were used to carry this high voltage. Finally, the first practical part (Simulink) was implemented through Mat lab (R2011a) and (R2013a) , On the other hand, the second practical part was in the lab, where servo motors Where used, variable and non - variable inductance , the drive to isolate the control loop from the power, PID and PWM, have also used the Arduino system to program the overdrive.
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حل سريان الاحمال وتحليل الاضطرابات في منظومات القدرة على اسس المنطق المضبب باستخدام دالة الكاوسين == Fuzzy Load Flow And Contingency Analysis Based On Gaussian Distribution System
اسم المؤلف:
یاسر فلاح حسن
اسم المشرف:
حسن عبد الله كبة
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:
This thesis presented durable minimization method for solving the load flow problem and contingency analysis in on - line applications. Because the electrical power networks are complicated systems, traditional (numerical) minimization methods may encounter difficulties in solving the load flow problem and contingency analysis due to properties of the problem.Thus, the fuzzy logic applications represented by the fuzzy load flow (FLF) and fuzzy contingency analysis (FCA) methods share the best selection in - stead of the traditional methods because the artificial intelligence (AI) methods do not use the characteristics of the problem to determine the next sampling point. The obtained results are very accurate with outstanding computation time, which made the FLF suitable for real time application. In addition to these features, the FLF also able to solve load flow problem of ill - conditioned power system and contingency analysis efficiently.The FLF method using Gaussian membership function requires less number of iterations and less computing time than that required in the FLF method using triangular membership function.All the obtained results show that the computation time of the Fuzzy Load Flow (FLF) is less than the Fast Decoupled Load Flow (FDLF). Using sparsity technique for the input sparse matrix data without complicating the algorithm?s programs gives reduction in overall computation time and storage requirements. The contingency ranking process by calculating the active power and voltage performance indices (PIP and PIV) are required for real power problems and voltage problems respectively for two typical test systems being the IEEE 14 - bus and 30 - bus systems. The performance of the FLF and FCA was tested on two typical test systems being the IEEE 14 - bus and 30 - bus systems in addition to the 362 - bus Iraqi National Grid.
👁 مشاهدة
نظام الاتمتة المنزلية مبني على اساس شبكة المتحسسات اللاسلكية == Home Automation System Based On Wireless Sensor Network
اسم المؤلف:
محمد قاسم شاكر
اسم المشرف:
اسامة قاسم جمعة
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2016
الموضوع الدقيق:
هندسة الالكترونيك والاتصالات
الدرجة:
ماجستير
الجامعة:
جامعة بابل - كلية الهندسة
اللغة:
الانكليزية
مكان الجامعة:
بابل
الصفحات الاولى:
👁 مشاهدة
تصميم منظومة اتصالات ضوئية لاسلكية خارجية اعتمادا على مازج تقسيمات الطول الموجي مع حزمة فائقة العرض == Design Of Outdoor WDM-UWB Based Optical Wireless Communication System
اسم المؤلف:
ياسر خضير عباس
اسم المشرف:
ابراهيم عبد الله مراداس
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2016
الموضوع الدقيق:
هندسة الالكترونيك والاتصالات
الدرجة:
ماجستير
الجامعة:
جامعة بابل - كلية الهندسة
اللغة:
الانكليزية
مكان الجامعة:
بابل
الصفحات الاولى:
👁 مشاهدة
تخطيط الشبكة الراديوية لنظام LTE == Radio Network Planning For LTE
اسم المؤلف:
عبيدة عبد الوهاب جاسم
اسم المشرف:
سامي محمد طاهر عبد الموجود
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2013
الموضوع الدقيق:
هندسة الاتصالات
الدرجة:
ماجستير
الجامعة:
جامعة الموصل
اللغة:
العربية
مكان الجامعة:
الموصل
الصفحات الاولى:
👁 مشاهدة
مسوق محرك حثي ثلاثي الطور متسامح العطب == Fault Tolerant Three Phase Induction Motor Drive
اسم المؤلف:
عمر محمد حسن عطية الجبوري
اسم المشرف:
ياسر محمد يونس امين
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2013
الموضوع الدقيق:
هندسة الكهرباء - قدرة ومكائن
الدرجة:
ماجستير
الجامعة:
جامعة الموصل
اللغة:
العربية
مكان الجامعة:
الموصل
الصفحات الاولى:
👁 مشاهدة
تحليل اخفاء الصور باستخدام الاحصاءات ذات المرتبة العالية == Image Steganalysis Using Higher Order Statistics
اسم المؤلف:
عمار موفق يعقوب يوسف دخان
اسم المشرف:
ماهر خضير العزاوي
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2005
الموضوع الدقيق:
هندسة الكهرباء
الدرجة:
ماجستير
الجامعة:
الجامعة المستنصرية - كلية الهندسة
اللغة:
الانكليزية
مكان الجامعة:
بغداد
الصفحات الاولى:
👁 مشاهدة
الشبكات اللاسلكية متعدد الهدف باستخدام خوارزمية التكيف الجينية == Multi-Objective Wireless Networks Using Adaptive Genetic Algorithm
اسم المؤلف:
علياء عبد الحسين
اسم المشرف:
ابراهيم قاسم ابراهيم
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2014
الموضوع الدقيق:
هندسة الكهرباء
الدرجة:
ماجستير
الجامعة:
جامعة بغداد
اللغة:
الانكليزية
مكان الجامعة:
بغداد
الصفحات الاولى:
👁 مشاهدة
تحسين تخمين الموقع الزاوي للهدف باستخدام الخوارزمية الجينية == Improvement Of Target Angular Location Estimation In Track-While-Scan Radar System Using Genetic Algorithms
اسم المؤلف:
حارث ماجد صالح الدليمي
اسم المشرف:
وليد خالد محمد علي | محمود طاهر محمد علي
الموضوع العام:
هندسة الكهرباء والالكترون والاتصالات
السنة:
2000
الموضوع الدقيق:
هندسة الكهرباء
الدرجة:
ماجستير
الجامعة:
الجامعة المستنصرية - كلية الهندسة
اللغة:
الانكليزية
مكان الجامعة:
بغداد
الصفحات الاولى:
👁 مشاهدة
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