Computer Engineering Commons^™

A New Approach Of Nonblind Watermarking Methods Based On Dwt And Svd Via Lu Decomposition, Onur Jane, Ersi̇n Elbaşi

Turkish Journal of Electrical Engineering and Computer Sciences

Multimedia security has been the focal point of considerable research activity in the last decade, mainly because of its wide application area. Watermarking, in particular, is identified as a major technology to achieve copyright protection and multimedia security. Therefore, recent studies in the literature include some evident approaches for embedding data into a multimedia element. Because of its useful frequency component separation, the discrete wavelet transform (DWT) is commonly used in watermarking schemes. Moreover, singular value decomposition (SVD) and lower-and-upper (LU) decomposition have little effect on the perception of the watermark. Therefore, in this study, a combination of DWT and …

Implementation Of Neural Network-Based Maximum Power Tracking Control For Wind Turbine Generators, Abdulhaki̇m Karakaya, Ercüment Karakaş

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the maximum power point tracking (MPPT) of a permanent magnet synchronous generator used in a wind generator system is realized by a prototype installed in a laboratory environment. The installed prototype is modeled in a MATLAB/Simulink environment. The MPPT is realized by an artificial neural network (ANN). The obtained simulation and experimental results are compared. The maximum power estimation at various windmill speeds (rpm) of the trained ANN in determined reference speeds is analyzed. The zero crossing points of the phases are determined by a digital signal peripheral interface controller and the system is operated according to …

Design And Implementation Of A Microcontroller Based Wind Energy Conversion System, Mehmet Demi̇rtaş, Şeri̇f Şerefoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a dsPIC-controlled DC/DC boost converter and a wind turbine control system that tracks the maximum power point are designed and implemented. In practice, the energy generated by a permanent magnet synchronous wind turbine is applied to the load using a circuit that consists of a rectifier, boost converter, and protective load. The converter operates in the designed mode 35% more efficiently than in the normal operation mode. In addition, the wind turbine is protected from overvoltages in strong windy weather using the protective circuit. Experimental results show that the ripple value on the direct current belonging to …

Optimization Of Job Shop Scheduling Problems Using Modified Clonal Selection Algorithm, Yilmaz Atay, Hali̇fe Kodaz

Turkish Journal of Electrical Engineering and Computer Sciences

Artificial immune systems (AISs) are one of the artificial intelligence techniques studied a lot in recent years. AISs are based on the principles and mechanisms of the natural immune system. In this study, the clonal selection algorithm, which is used commonly in AISs, is modified. This algorithm is applied to job shop scheduling problems, which are one of the most difficult optimization problems. For applying application results to the optimum solution, parameter values giving the optimum solution are determined by analyzing the parameters in the algorithm. The obtained results are given in detail in the tables and figures. The best …

Study On Interior Permanent Magnet Synchronous Motors For Hybrid Electric Vehicle Traction Drive Application Considering Permanent Magnet Type And Temperature, Javad Soleimani, Abolfazl Vahedi, Abdolhossein Ejlali, Mohammadhossein Barzegari Bafghi

Turkish Journal of Electrical Engineering and Computer Sciences

Recently, interior permanent magnet synchronous motors (Interior-PMSMs) have become known as a good candidate for hybrid electric vehicle (HEV) traction drive application due to their unique merits. However, the dynamic and steady-state behaviors of these motors are quite dependent on the permanent magnet (PM) type, configuration, and volume in rotor structures. This paper uses a novel structure of Interior-PMSMs for traction applications with fragmental buried rotor magnets in order to achieve low torque ripple, iron losses, and cogging torque. In this paper, first, the effect of the PM type on a d-q equivalent circuit model is examined. Next, the design …

A New Psfb Converter-Based Inverter Arc Welding Machine With High Power Density And High Efficiency, İsmai̇l Aksoy

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a high-performance single-phase inverter arc welding machine is presented. Power control of the developed welding machine is realized with a high-frequency, phase-shifted full bridge (PSFB) pulse-width modulation (PWM) converter. The PSFB PWM converter operates with soft switching at no load and full load. There is no need to use a passive snubber in the converter. Welding machine control is implemented with a digital signal processor (DSP) and phase-shift PWM IC. By means of the DSP, advanced arc welding functions and protection features such as short-circuit, over-current, and temperature protection are achieved. The current and voltage waveforms given …

Quantitative Modeling Of Reliability And Survivability For Cyber-Physical Power Systems, Murtadha Nabeel Albasrawi

Masters Theses

"Critical infrastructure systems are increasingly reliant on cyber infrastructure that enables intelligent real-time control of physical components. This cyber infrastructure utilizes environmental and operational data to provide decision support intended to increase the efficacy and reliability of the system and facilitate mitigation of failure. Realistic imperfections, such as corrupt sensor data, software errors, or failed communication links can cause failure in a functional physical infrastructure, defying the purpose of intelligent control. As such, justifiable reliance on cyber-physical critical infrastructure is contingent on rigorous investigation of the effect of intelligent control, including modeling and simulation of failure propagation within the cyber-physical …

Computer Vision Libraries For Trailer Truck Testbed Using Open Source Computer Vision Libraries, Krishnan Raghavan

Masters Theses

"Computer Vision is a field that aims at understanding and analyzing images from the real world to produce numerical and symbolical data. It is a first step at duplicating the capabilities of human vision by electronically understanding the image and perceiving its features. This work aims at providing some of the features of a human eye to a trailer truck. These features include getting a 3D wireframe from continuous images and prediction of the next position of the objects in view, while the truck is moving.

The thesis has been divided into 3 sections. First section is acquiring images in …

Computation Of Cross-Talk Alignment By Mixed Integer Linear Programming, Qifeng Chen

Masters Theses

"Noise analysis has been an important and difficult part of design flow of very large-scale integrated (VLSI) systems in many years. In this thesis, the problem of signal alignment resulting in possible maximum peak interconnect coupling noise and propose a variation aware technique for computing combined noise pulse taking into account timing constraints on signal transitions has been discussed. This work shows that the worst noise alignment algorithm can be formulated as mixed integer programming (MLIP) problem both in deterministic window cases and variational window cases. For deterministic window cases, it is assumed that timing windows are given for each …

Software-Based Instrumentation For Analysis Of Electrostatic Discharge Effects, Antonio James Sabatini

Masters Theses

”Failures caused by electrostatic discharge (ESD) compromise the reliability of embedded systems. Peripherals such as the universal serial bus (USB) are particularly vulnerable, as isolating them to avoid electromagnetic interference would defy their purpose - facilitating communication with and/or by the embedded system. Better understanding the propagation of failures that result from ESD can facilitate defensive development of hardware and software for embedded systems, but is hampered by the lack of non-invasive and lightweight instrumentation techniques.

The original contribution of this thesis is the design and development of software-based instrumentation for monitoring the reaction of the USB peripheral of an …

Password Protected Visual Cryptography Via Cellular Automaton Rule 30, Roman V. Yampolskiy, Jovan D. Rebolledo-Mendez, Musa M. Hindi

Faculty and Staff Scholarship

Visual cryptography depends on two shares. The initial configuration, extra security bits and the number of the rule for the CA along with the number of computed steps serve as a password for a visually encrypted image. The second share could contain a predefined pattern; the developed algorithm uses a snapshot of a CA after a certain number of steps to generate the predefined share. Only one of these shares has to be random. The developed encryption system is a hybrid between visual and classical cryptographic approaches. It requires less storage space compared to a standalone visual encryption system and …

Frequency Selective Surfaces For Extreme Applications, Jay Houston Barton

Open Access Theses & Dissertations

It is known that for high-power microwaves and other extreme environments, the use of resonant metallic elements in frequency selective surfaces can be problematic. The solution developed within this Dissertation to solve these problems was to use guided-mode resonance phenomenon to create all-dielectric frequency selective surfaces that could survive these extreme environments.

To fully understand how these devices work, three different computational electromagnetic methods are formulated and implemented. The formulation of these methods start with the differential form of Maxwellâ??s equation and are derived all the way down to the final simulation state. This is done sequentially and all the …

Myspace, Inc. V. Graphon Corp.: Ignoring The Basic Premise That 101 Must Come Before 102 And 103, Emmanuel A. Fishelman

Journal of Business & Technology Law

No abstract provided.

“Time For Some Traffic Problems”: Enhancing E-Discovery And Big Data Processing Tools With Linguistic Methods For Deception Detection, Erin S. Crabb

Journal of Digital Forensics, Security and Law

Linguistic deception theory provides methods to discover potentially deceptive texts to make them accessible to clerical review. This paper proposes the integration of these linguistic methods with traditional e-discovery techniques to identify deceptive texts within a given author’s larger body of written work, such as their sent email box. First, a set of linguistic features associated with deception are identified and a prototype classifier is constructed to analyze texts and describe the features’ distributions, while avoiding topic-specific features to improve recall of relevant documents. The tool is then applied to a portion of the Enron Email Dataset to illustrate how …

Fast Rtp Detection And Codecs Classification In Internet Traffic, Petr Matousek, Ondrej Rysavy, Martin Kmet

Journal of Digital Forensics, Security and Law

This paper presents a fast multi-stage method for on-line detection of RTP streams and codec identification of transmitted voice or video traffic. The method includes an RTP detector that filters packets based on specific values from UDP and RTP headers. When an RTP stream is successfully detected, codec identification is applied using codec feature sets. The paper shows advantages and limitations of the method and its comparison with other approaches. The method was implemented as a part of network forensics framework NetFox developed in project SEC6NET. Results show that the method can be successfully used for Lawful Interception as well …

Relating Admissibility Standards For Digital Evidence To Attack Scenario Reconstruction, Changwei Liu, Anoop Singhal, Duminda Wijesekera

Journal of Digital Forensics, Security and Law

Attackers tend to use complex techniques such as combining multi-step, multi-stage attack with anti-forensic tools to make it difficult to find incriminating evidence and reconstruct attack scenarios that can stand up to the expected level of evidence admissibility in a court of law. As a solution, we propose to integrate the legal aspects of evidence correlation into a Prolog based reasoner to address the admissibility requirements by creating most probable attack scenarios that satisfy admissibility standards for substantiating evidence. Using a prototype implementation, we show how evidence extracted by using forensic tools can be integrated with legal reasoning to reconstruct …

A Study Of Forensic Imaging In The Absence Of Write-Blockers, Gary C. Kessler, Gregory H. Carlton

Journal of Digital Forensics, Security and Law

Best practices in digital forensics demand the use of write-blockers when creating forensic images of digital media, and this has been a core tenet of computer forensics training for decades. The practice is so ingrained that the integrity of images created without a write-blocker are immediately suspect. This paper describes a research framework that compares forensic images acquired with and without utilizing write-blockers in order to understand the extent of the differences, if any, in the resultant forensic copies. We specifically address whether differences are superficial or evidentiary, and we discuss the impact of admitting evidence acquired without write blocking. …

Automated Evaluation Of Approximate Matching Algorithms On Real Data, Frank Breitinger, Vassil Roussev

Electrical & Computer Engineering and Computer Science Faculty Publications

Bytewise approximate matching is a relatively new area within digital forensics, but its importance is growing quickly as practitioners are looking for fast methods to screen and analyze the increasing amounts of data in forensic investigations. The essential idea is to complement the use of cryptographic hash functions to detect data objects with bytewise identical representation with the capability to find objects with bytewise similarrepresentations.

Unlike cryptographic hash functions, which have been studied and tested for a long time, approximate matching ones are still in their early development stages and evaluation methodology is still evolving. Broadly, prior approaches have …

Perception Based Misunderstandings In Human-Computer Dialogues, Niels Schütte, John D. Kelleher, Brian Mac Namee

Articles

In a situated dialogue, misunderstandings may arise if the participants perceive or interpret the environment in different ways. In human-computer dialogue this may be due the sensor errors. We present an experiment system and a series of experiments in which we investigate this problem.

Lightweight Data Compression In Wireless Sensor Networks Using Huffman Coding, Henry P. Medeiros, Marcos C. Maciel, Richard D. Souza, Marcelo E. Pellenz

Electrical and Computer Engineering Faculty Research and Publications

This paper presents a lightweight data compression method for wireless sensor networks monitoring environmental parameters with low resolution sensors. Instead of attempting to devise novel ad hoc algorithms, we show that, given general knowledge of the parameters that must be monitored, it is possible to efficiently employ conventional Huffman coding to represent the same parameter when measured at different locations and time periods. When the data collected by the sensor nodes consists of integer measurements, the Huffman dictionary computed using statistics inferred from public datasets often approaches the entropy of the data. Results using temperature and relative humidity measurements show …