Engineering Commons^™

Induction Motor, State Estimation, Extended Kalman Filtering, Recurrent Neural Networks, Saadetti̇n Aksoy, Aydin Mühürcü

Turkish Journal of Electrical Engineering and Computer Sciences

This study presents a recurrent neural network (RNN)-based nonlinear state estimator that uses an Elman neural network structure (ENN) for state estimation of a squirrel-cage induction motor. The proposed algorithm only uses the measurements of the stator currents and the rotor angular speed, and it learns the dynamic behavior of the state observer from these measurements through prediction error minimization. A squirrel-cage induction motor was fed from sinusoidal, 6-step, and pulse-width modulation (PWM) supply sources at different times in order to observe the performance of the proposed estimator for different operation conditions. Estimation results showed that the proposed algorithm is …

A Stationary, Variable Dof Flight Control System For An Unmanned Quadrocopter, Vasfi̇ Emre Ömürlü, Ahmet Kirli, Utku Büyükşahi̇n, Şeref Naci̇ Engi̇n, Sedat Kurtoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Unmanned air vehicles (UAV) and especially quadrocopters have drawn great attention in recent years because of their maneuverability and nonlinear control problem. Most of the related research concentrate on control; yet, design and communication are also some sub-topics. In this paper, a stationary, four rotor air vehicle with limited/controlled degree of freedom is constructed so that various control algorithms and their changing effects with varying vehicle dynamics can be studied on the ground for safety purposes. Ascending/descending, pitch/yaw/roll motions can be limited by setting the vehicle's degree of freedom mechanically, resulting better net observability of the control algorithms on the …

A Luenberger-Sliding Mode Observer With Rotor Time Constant Parameter Estimation In Induction Motor Drives, Mustafa Gürkan Aydeni̇z, İbrahi̇m Şenol

Turkish Journal of Electrical Engineering and Computer Sciences

The performance and efficiency of an induction motor drive system can be enhanced by online estimation of critical parameters such as rotor time constant. A novel Luenberger-sliding mode observer with a parameter adaptation algorithm is proposed in this paper to compensate for the parameter variation effects. The observer is comparably simple and robust relative to the previously developed observers, and yet suitable for online implementation. Simulation studies for the proposed method were conducted in a MATLAB environment. Observer constants and the control parameters were tuned during the simulation studies and used during the experimental study stage. Experimental verification of the …

Using Learning Automata For Multi-Objective Generation Dispatch Considering Cost, Voltage Stability And Power Losses, Ari̇f Karakaş, Celal Kocatepe, Fangxing Li

Turkish Journal of Electrical Engineering and Computer Sciences

The economical and secure operation of power systems has significant importance. Due to technical limitations, the best economical operation point is not always the desired operating point for system stability or power losses. In this study, first, the most economical operating point is obtained by solving the non-linear, network-constrained economic dispatch problem using a genetic algorithm. Then, the system voltage stability is analyzed to compare the different possible operating points using V-Q sensitivity analysis. The power losses, obtained for various operating points, are considered the third objective function. Finally, these 3 aspects of cost, voltage stability, and power losses are …

Change Detection Without Difference Image Computation Based On Multiobjective Cost Function Optimization, Turgay Çeli̇k, Zeki̇ Yetgi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we propose a novel method for unsupervised change detection in multi-temporal satellite images by using multiobjective cost function optimization via genetic algorithm (GA). The spatial image grid of the input multi-temporal satellite images is divided into two distinct regions, representing ``changed'' and ``unchanged'' regions between input images, via the intermediate change detection mask produced by the GA. The dissimilarity of pixels of ``changed'' regions and similarity of pixels of ``unchanged'' regions between input multi-temporal images are measured using image quality metrics which consider correlation, spectral distortion, radiometric distortion, and contrast distortion. The contextual information of each pixel …

Statistical Significance Based Graph Cut Regularization For Medical Image Segmentation, Sema Candemi̇r, Yusuf Si̇nan Akgül

Turkish Journal of Electrical Engineering and Computer Sciences

Graph cut minimization formulates the image segmentation as a linear combination of problem constraints. The salient constraints of the computer vision problems are data and smoothness which are combined through a regularization parameter. The main task of the regularization parameter is to determine the weight of the smoothness constraint on the graph energy. However, the difference in functional forms of the constraints forces the regularization weight to balance the inharmonious relationship between the constraints. This paper proposes a new idea: bringing the data and smoothness terms on the common base decreases the difference between the constraint functions. Therefore the regularization …

Investigation Of Luhn's Claim On Information Retrieval, İlker Kocabaş, Beki̇r Taner Di̇nçer, Bahar Karaoğlan

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we show how Luhn's claim about the degree of importance of a word in a document can be related to information retrieval. His basic idea is transformed into z-scores as the weights of terms for the purpose of modeling term frequency (tf) within documents. The Luhn-based models represented in this paper are considered as the TF component of proposed TF \times IDF weighing schemes. Moreover, the final term weighting functions appropriate for the TF \times IDF weighting scheme are applied to TREC-6, -7, and -8 databases. The experimental results show relevance to Luhn's claim by having high …

The Journal Of Undergraduate Research: Volume 09

The Journal of Undergraduate Research

This is the complete issue of the South Dakota State University Journal of Undergraduate Research, Volume 13.

Vibrational Analysis Of Soloflex Whole Body Vibration Platform, Zachary Croatt, Josh Robers

The Journal of Undergraduate Research

A Soloflex Whole Body Vibration (WBV) Platform was tested for its frequency and magnitude of vibration at multiple settings on the supplied dial. An accelerometer was used to measure the vibrations on different points mapped across the platform. The motor attached to the board was also tested for its frequency using a high-speed camera. The amplitude measurements found from the accelerometer data was compared to the readings on the supplied control module to “calibrate” the platform for medical testing.

Vibrational Analysis Of An Electromechanical Toothbrush, Mark Wager

The Journal of Undergraduate Research

The effectiveness of an electromechanical toothbrush is based entirely on its ability to remove plaque through vibrations. This paper contests that the three-dimensional motion of more inexpensive models of electromechanical toothbrushes can be accurately modeled in one-dimension so as to predict the motion of future toothbrush designs using simply the material properties, motor specifications, and grip design. Vibrational modeling, mathematical modeling, and experimentation were used in the analysis to confirm the outcome of the study and the assumptions of the model.

Design And Ground Plane Optimization Of A Cpw-Fed Ultra-Wideband Antenna, Mohammed Al-Husseini, Ali Ramadan, Youssef Tawk, Ali El-Hajj, Karim Y. Kabalan

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, an ultra-wideband antenna based on an egg-shaped conductor and a co-planar waveguide (CPW) feed is presented. The ground plane incorporates an egg-shaped slot with parametrized center and dimensions. By resizing the slot and moving its center, a slotted or a partial ground can be obtained. Based on this configuration, a parametric study that aims at achieving the best ultra-wideband (UWB) response of the antenna is done. The study shows that an excellent UWB response is achieved for a certain ground slot size, beyond which the response starts to degrade. However, as the slot size tends to infinity, …

Application Of A Hybrid Evolutionary Technique For Efficiency Determination Of A Submersible Induction Motor, Mümtaz Mutluer, Osman Bi̇lgi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

Electric motors are the largest consumers of electricity in plants and induction motors constitute nearly two-thirds of them. The replacement of in-service induction motors with more efficient ones is a very important strategy for energy savings and consequently nearly 30 different methods have been used to determine the efficiency of induction motors in the last 2 decades. This paper aims to develop the efficiency determination of a 20 Hp submersible induction motor. Due to getting perfect efficiency of the submersible induction motor, a robust hybrid evolutionary optimization technique, which consists of a genetic algorithm and simulated annealing, is used. The …

An Algorithm To Minimize Within-Class Scatter And To Reduce Common Matrix Dimension For Image Recognition, Ümi̇t Çi̇ğdem Turhal, Alpaslan Duysak

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new algorithm using 2DPCA and Gram-Schmidt Orthogonalization Procedure for recognition of face images is proposed. The algorithm consists of two parts. In the first part, a common feature matrix is obtained; and in the second part, the dimension of the common feature matrix is reduced. Resulting common feature matrix with reduced dimension is used for face recognition. Column and row covariance matrices are obtained by applying 2DPCA on the column and row vectors of images, respectively. The algorithm then applies eigenvalue-eigenvector decomposition to each of these two covariance matrices. Total scatter maximization is achieved taking the …

Design And Development Of Workstation For Microparts Manipulation And Assembly, Emrah Deni̇z Kunt, Ahmet Teoman Naskali̇, İslam Shoukry Mohammed Khalil, Asif Sabanovic, Ebubeki̇r Yüksel

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, microassembly system design issues are discussed with requirements, constraints and necessities for the development of an assembly platform, and these issues are shown over a versatile and reconfigurable microassembly workstation which is designed and realized as a research tool for investigation of the problems in microassembly and micromanipulation tasks. First prototype of a workstation and the development of a second prototype with enhancements on mechanical and control structure of the system are presented with details on the configuration of the systems. In addition, several experiments using a workstation are presented both on the first and the second …

Column: File Cabinet Forensics, Simson Garfinkel

Journal of Digital Forensics, Security and Law

Researchers can spend their time reverse engineering, performing reverse analysis, or making substantive contributions to digital forensics science. Although work in all of these areas is important, it is the scientific breakthroughs that are the most critical for addressing the challenges that we face. Reverse Engineering is the traditional bread-and-butter of digital forensics research. Companies like Microsoft and Apple deliver computational artifacts (operating systems, applications and phones) to the commercial market. These artifacts are bought and used by billions. Some have evil intent, and (if society is lucky), the computers end up in the hands of law enforcement. Unfortunately the …

Column: Putting The Science In Digital Forensics, Fred Cohen

Journal of Digital Forensics, Security and Law

In a recent study, digital forensics was found to lack a consensus around even the most basis notions and terminology of the field. To quote: “These two preliminary studies individually suggest that (1) scientific consensus in the area of digital forensic evidence examination is lacking in the broad sense, but that different groups within that overall community may have limited consensus around areas in which they have special expertise, and (2) that the current peerreviewed publication process is not acting to bring about the sorts of elements typically found in the advancement of a science toward such a consensus. ... …

Technology Corner: Internet Packet Sniffers, Nick V. Flor, Kenneth Guillory

Journal of Digital Forensics, Security and Law

The best way to understand an internet packet sniffer, hereafter “packet sniffer”, is by analogy with a wiretap. A wiretap is a piece of hardware that allows a person to eavesdrop on phone conversations over a telephone network. Similarly, a packet sniffer is a piece of software that allows a person to eavesdrop on computer communications over the internet. A packet sniffer can be used as a diagnostic tool by network administrators or as a spying tool by hackers who can use it to steal passwords and other private information from computer users. Whether you are a network administrator or …

Sampling: Making Electronic Discovery More Cost Effective, Milton Luoma, Vicki Luoma

Journal of Digital Forensics, Security and Law

With the huge volumes of electronic data subject to discovery in virtually every instance of litigation, time and costs of conducting discovery have become exceedingly important when litigants plan their discovery strategies. Rather than incurring the costs of having lawyers review every document produced in response to a discovery request in search of relevant evidence, a cost effective strategy for document review planning is to use statistical sampling of the database of documents to determine the likelihood of finding relevant evidence by reviewing additional documents. This paper reviews and discusses how sampling can be used to make document review more …

Column: The Physics Of Digital Information, Fred Cohen

Journal of Digital Forensics, Security and Law

No abstract provided.

Developing A Forensic Continuous Audit Model, Grover S. Kearns, Katherine J. Barker, Stephen P. Danese

Journal of Digital Forensics, Security and Law

Despite increased attention to internal controls and risk assessment, traditional audit approaches do not seem to be highly effective in uncovering the majority of frauds. Less than 20 percent of all occupational frauds are uncovered by auditors. Forensic accounting has recognized the need for automated approaches to fraud analysis yet research has not examined the benefits of forensic continuous auditing as a method to detect and deter corporate fraud. The purpose of this paper is to show how such an approach is possible. A model is presented that supports the acceptance of forensic continuous auditing by auditors and management as …

Analysis Of Data Remaining On Second Hand Adsl Routers, Patryk Szewczyk

Journal of Digital Forensics, Security and Law

In theory, an ADSL router can provide an additional layer of security to a wired and wireless network through; access control, wireless encryption, firewall rule sets, and network event logging. An ADSL router may also contain the users’ usage habits and broadband account credentials. However, end-users may be unaware of the intricacies of the security measures available and the potentially confidential information stored on their device. As a result a second hand ADSL router may contain a wealth of user-specific information if not wiped and disposed of in a secure manner. This paper shows the data that was acquired from …

Book Review: Online Privacy: Issues In The Digital Age, Darlene M. Tester

Journal of Digital Forensics, Security and Law

This book is one of a series of books Currie has written about online areas of concern. This is the sixth book in the series. The purpose of the book is to act as a primer for people in the IT field who may need a point of reference for Internet issues such as gaming, security and privacy. The book takes a high level look at the complexities of privacy online from social networking to hackers and provides insight into what the most pressing issues of privacy are online today.

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

Technology Corner: Virtual Crime Scene Reconstruction: The Basics Of 3d Modeling, Nick V. Flor

Journal of Digital Forensics, Security and Law

Digital crime scenes take place in the context of physical crime scenes. Virtual crime scene reconstruction is an activity where investigators create a 3- dimensional (3-D) model of an actual crime scene for the purpose of determining the events that lead to the crime. While virtual crime scene reconstruction is currently used for analyzing physical scenes, it can also help investigators visualize and explore ways digital media could have been used to perpetrate a crime. In this technology corner we explore one of the technologies underlying virtual crime scene reconstruction: 3-D modeling.

Working Inside The Box: An Example Of Google Desktop Search In A Forensic Examination, Timothy J. Latulippe

Journal of Digital Forensics, Security and Law

Information and the technological advancements for which mankind develops with regards to its storage has increased tremendously over the past few decades. As the total amount of data stored rapidly increases in conjunction with the amount of widely available computer-driven devices being used, solutions are being developed to better harness this data. These types of advancements are continually assisting investigators and computer forensic examiners. One such application which houses copious amounts of fruitful data is the Google Desktop Search program. Coupled with tested and verified techniques, examiners can exploit the power of this application to cater to their investigative needs. …

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

Book Review: Iphone And Ios Forensics: Investigation, Analysis And Mobile Security For Apple Iphone, Ipad And Ios Devices, Christopher Schulte

Journal of Digital Forensics, Security and Law

These are exciting times for Digital Forensics practitioners. While our examinations of mobile devices (including cell phones and tablet computers) continue to bring new and sometimes hair-pulling challenges into our labs and on-site engagements, research and understanding of these tiny computers is increasing at what seems an exponential rate. This is especially true in the iOS (Apple Computer’s mobile operating system that powers the iPhone, iPad, iPod Touch and Apple TV) space. The diligent work of talented computer scientists in this field allows examiners everywhere to reap the benefits of easier, faster and more effective examinations that yield more accurate …

Investigating Modern Communication Technologies: The Effect Of Internet-Based Communication Technologies On The Investigation Process, Matthew Simon, Jill Slay

Journal of Digital Forensics, Security and Law

Communication technologies are commonplace in modern society. For many years there were only a handful of communication technologies provided by large companies, namely the Public Switched Telephone Network (PSTN) and mobile telephony; these can be referred to as traditional communication technologies. Over the lifetime of traditional communication technologies has been little technological evolution and as such, law enforcement developed sound methods for investigating targets using them. With the advent of communication technologies that use the Internet – Internet-based or contemporary communication technologies – law enforcement are faced with many challenges. This paper discusses these challenges and their potential impact. It …

Computational Investigation Of Particle Settling Effects On Inhaled Submicron Bioaerosol Deposition In The Human Lung, Mohammed Ali, Essam A. Ibrahim

Early Career Technical Journal (ECTJ)

Proceedings of the ASME Early Career Technical Conference, November 4-5, 2011. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia

pp. 1-5

Dynamic Modeling And Parameter Estimation For Impact Analysis And Robust Packaging Design, Thomas M. Stone, Seung-Kyum Choi, Hemanth Amarchinta

Early Career Technical Journal (ECTJ)

Proceedings of the ASME Early Career Technical Conference, November 4-5, 2011. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia

pp. 6-13