Congestion control is among the fundamental problems of Internet multicast. It is an active research area with many challenges. In this study, an introduction to Internet congestion control and a brief literature survey of current multicast congestion control protocols is presented. Then two recently proposed &ldquo / single-rate, end-to-end, rate based&rdquo / class of protocols, namely LESBCC and TFMCC are evaluated with respect to their intersession fairness (TCP-friendliness), smoothness and responsiveness criteria. Throughout the experiments, which are conducted using a widely accepted network simulation tool &lsquo / ns&rsquo / , different topologies have been employed.

This thesis analyzes the concept of robot mimicking in the field of Human-Machine Interaction (HMI). Gestures are investigated for HMI applications and the preliminary work of the mimicking of a model joint with markers is presented. Two separate systems are proposed finally which are capable of detecting a moving human arm in a video sequence and calculating the orientation of the arm. The angle of orientation found is passed to robot arm in order to realize robot mimicking. The simulations show that it is possible to determine human arm orientation either by using some markers or some initial background image information or tracking of features.

In this thesis, the Test Driven Development method (TDD) is studied for use in developing embedded software. The required framework is written for the development environment Rhapsody. Integration of TDD into a classical development cycle, without necessitating a transition to agile methodologies of software development and required unit test framework to apply TDD to an object oriented embedded software development project with a specific development environment and specific project conditions are done in this thesis. A software tool for unit testing is developed specifically for this purpose, both to support the proposed approach and to illustrate its application. The results show that RhapUnit supplies the required testing functionality for developing embedded software in Rhapsody with TDD. Also, development of RhapUnit is a successful example of the application of TDD.

This thesis introduces a novel mobility model based on so called &ldquo / 2D correlated diffusion process&rdquo / . In this model, motion components over x and y axes are dependent. Joint density function of the process is derived. The expected exit time from an arbitrary domain is characterized by a boundary value problem. Analytical solution of this problem is given for a specific case. Numerical solution of the problem is presented by several examples. The results obtained in these examples are verified by simulations. The expected exit time computed by this method holds for any given 2D domain and any given starting position inside.

REROUTE SEQUENCE PLANNING IN MULTIPROTOCOL LABEL SWITCHING NETWORKS &Ouml / zbilgin, izzet G&ouml / khan M.S., Department of Electrical and Electronics Engineering Supervisor: Asst. Prof. Dr. C&uuml / neyt F. Bazlama&ccedil / ci December 2004, 57 pages The growth of the Internet has caused the development of new protocols that enable IP networks to be engineered efficiently. One such protocol, Multiprotocol Label Switching (MPLS) enables IP datagrams in backbone networks to be forwarded based on the label switching forwarding paradigm. In MPLS networks, rerouting of Label Switching Paths (LSPs) can be needed in order to attain a better resource utilization in the network. In this case, a sequence of LSPs has to be found for their one by one reconfiguration without service interruption, involving the constraint that the link capacities should not be violated at any time during the rerouting process. This reroute sequence planning problem for LSPs is NP-complete. In previous works, the conditions of existence of any feasible reroute sequence are examined and algorithms are described for solving the problem, but it was shown that the problem is computationally hard in real-world situations because of the large amount of routers and LSPs in the network. In this work, we deal with the problem of reroute sequence planning problem of LSPs and present alternative solutions for the case when there is no feasible solution. We introduce a tool for the post-processing phase when a capacity violation is occurred during the sequence planning. We present an algorithm trying to reconfigure LSPs while allowing some interruption or degradation of traffic during the rerouting process.

Generation of photo-realistic 3D human face models is a hot topic in the area joining computer graphics and computer vision. Many different techniques are used for this purpose, but most of them are not feasible for home users. These techniques may use advanced hardware such as laser scanners, calibrated stereo cameras, or very sophisticated software that can be as expensive as advanced hardware. Face model generation by morphing an initial 3D model with uncalibrated camera photographs is studied in this thesis. Manually marked feature points on photographs are used to deform initial 3D face model. Initial photographs also are processed to form a single texture image covering deformed 3D face model.

In this work, reinforcement learning algorithms are studied with the help of potential field methods, using robosoccer simulators as test beds. Reinforcement Learning (RL) is a framework for general problem solving where an agent can learn through experience. The soccer game is selected as the problem domain a way of experimenting multi-agent team behaviors because of its popularity and complexity.

This thesis explains the design of a microcontroller-based device, which provides an efficient and practical alternative for the remote reading of digital electricity meters over Public Switch Telephone Network (PSTN). As an alternative application, a system is constructed providing file transfer capability to the PC connected to the port of implemented device in addition to remote reading of digital electricity meters. This thesis also provides detailed explanations about the basics of serial asynchronous communication over modem for PICs (peripheral interface controllers) together with description of each component included by the constructed system, which can be used in energy metering sector commonly.

ABSTRACT A DEPENDABLE COMPUTING APPLICATION G&uuml / ng&ouml / r, Ugur M.S., Department of Electric and Electronics Engineering Supervisor : Prof. Dr. Hasan Cengiz G&uuml / ran April 2005, 129 pages This thesis focuses on fault tolerance which is kind of dependable computing implementation. It deals with the advantages of fault tolerance techniques on Single Event Upsets (SEU) occurred in a Field Programmable Gate Array (FPGA). Two fault tolerant methods are applied to floating point multiplier. Most common SEU mitigation method is Triple Modular Redundancy (TMR). So, two fault tolerance methods, which use TMR, are tested. There are three printed circuit boards (PCBs) and one user interface software in the setup. By user interface software running on a computer, user can inject fault or faults to the selected part of the system, which uses TMR with voting circuit or TMRVC TMR with voting and correction circuits on floating point multiplier. After inserting fault or faults, user can watch results of the fault injection test by user interface software. One of these printed circuit boards is called as a Test Pattern Generator. It is responsible for communication between the Fault Tolerant Systems and the user interface software running on a computer. Fault Tolerant Systems is second PCB in the setup. It is used to implement fault tolerant methods on fifteen bits floating point multiplier in the FPGA. First one of these methods is TMR with voter circuit (TMRV) and second one is TMR with voter and correction circuits (TMRVC). Last PCB in the setup is Display PCB. This PCB displays fault tolerant test result and floating point multiplication result. All the functions on Test Pattern Generator and Fault Tolerant Systems are implemented through the use of a Field Programmable Gate Array (FPGA), which is programmed using the Very High Speed IC Description Language (VHDL). Implementation results of the used methods in FPGA are evaluated to observe the performance of applied methods for tolerating SEU.

ABSTRACT SOFT DECODING OF CONVOLUTIONAL PRODUCT CODES ON AN FPGA PLATFORM Sanli, Mustafa M.Sc., Department of Electrical and Electronics Engineering Supervisor: Asst. Prof. Dr. Ali &Ouml / zg&uuml / r YILMAZ September 2005, 79 pages In today&rsquo / s world, high speed and accurate data transmission and storage is necessary in many fields of technology. The noise in the transmission channels and read-write errors occurring in the data storage devices cause data loss or slower data transmission. To solve these problems, the error rate of the received information must be minimized. Error correcting codes are used for detecting and correcting the errors. Turbo coding is an efficient error correction method which is commonly used in various communication systems. In turbo coding, some redundancy is added to the data to be transmitted. The redundant data is used to recover original data from the received data. MAP algorithm is one of the most commonly used soft decision decoding algorithms. In this thesis, hardware implementation of the MAP algorithm is studied. MAP decoding is verified on an FPGA. Virtex2Pro is the platform of choice in this study. The algorithm is written in the VHDL language. A MAP decoder is designed and its operation is verified. Using many MAP decoders concurrently, a convolutional product decoder is implemented as well. Area and speed limitations are discussed.