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

Author name: سارة رعد قاسم
Supervisor name: زينب توفيق باقر
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: هيثم سعدون عفتان
Supervisor name: نزار هادي عباس
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: 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.

تقليل تموج عزم الدوران في طريقة السيطرة المباشرة لعزم الدوران للمحركات الحثية == Torque Ripple Reduction Based Direct Torque Control For Induction Motor Drives

Author name: حيدر سالم حميد
Supervisor name: Prof. Dr. J.H. Alwash | Hanan M. Habbi
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: 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.

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

Author name: یاسر فلاح حسن
Supervisor name: حسن عبد الله كبة
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: 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.

System Identification Applied to Selected Practical Systems

Author name: Saad Shakir Tawfiq Al-Sekafi
Supervisor name: Taha T. Al-Naimy
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

INVESTIGATION IN THE DESIGN OF A FORTRAN COMPILER SYSTEM

Author name: RA'ED MOHEY SHAWI
Supervisor name: A. K. BAHRANI
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

CHARACTERISTICS OF A LINEAR ANTENNA IN WAVEGUIDES

Author name: khalid mohammed al-mashhadani
Supervisor name: mohammed j. al-hakkak
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تقييم اداء وتصميم محركات القطب المظلل

Author name: سعد طه ياسين
Supervisor name: اسماعيل عبد الله محمد
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering - Power and Machinery
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
Language: Arabic
University location: Baghdad
First pages:

Measurement Of Telephone Channel Characteristics Using Dsp Technique

Author name: عامر اسطيفان عبد الاحد
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical, Electronic and Communications Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

تغيير سرعة المحركات بواسطة الطور المثال

Author name: مقداد ذنون يونس
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

Development Of Low Bit Rate Vocoder

Author name: محمد عبد الوهاب قاسم الهاشمي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

Communication Based On Side Band Rectification

Author name: هادي طارش زبون
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

Based Control Of A Naclear Reactor

Author name: نافع جميل كوركيس
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

Automatic Frequency Control System Clarifiers For Suppressed Carrier Ssb Speech Communiacation

Author name: حسن واريوش حلو
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

تحضير اللثيوم مع العناصر المختلفة والمعالجة الحرارية النظرية باستخدام الليزر

Author name: عباس علي محمود عمران
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Doctorate
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

دراسة تجريبية لتراتيب مختلفة للقصب كعازل حراري وصوتي

Author name: سامر سيف الدين بهاء الدين
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

انتقال الحرارة اثناء تجفيف البطاطا الحلوة بالهواء

Author name: شيماء محمد امين
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

The Effect Of Variation Of Nonlinear Load On Power Factor Of The AC Supply Network

Author name: محمد عبد الله عبد السادة
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

Performance Study Of Helical Winding Lubular Liner Induction Motor

Author name: اسلان صباح عبد
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

Modified RTCE Techniques For HF Channel

Author name: عيسى جعفر عيسى
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

Image Recognition Using Wavelet Transform

Author name: امير وائل عرب
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

Generation Rescheduting For Alleviating Over Loads Cansed By Contingency

Author name: ياسر ناظم العاني
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

Event Processor In SCADA System

Author name: زينب نوري غانم
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

Design And Implementation Of Telephone Tester

Author name: ملاذ صلاح الدين القزويني
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad

Design And Implementation Of Center To Center Computer Cmmunication Protocols

Author name: حيدر عبد الله دواشي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: University of Baghdad - College Of Engineering - Department Of Electrical Engineering
University location: Baghdad
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