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Full-Text Articles in Engineering

Statistical Model Of Hot-Carrier Degradation And Lifetime Prediction For P-Mos Transistors, Firat Kaçar, Ayten Kuntman, Hakan Kuntman Jan 2006

Statistical Model Of Hot-Carrier Degradation And Lifetime Prediction For P-Mos Transistors, Firat Kaçar, Ayten Kuntman, Hakan Kuntman

Turkish Journal of Electrical Engineering and Computer Sciences

Along with advances in microelectronics, and computer and space technologies, device dimensions are becoming smaller; as a result, hot-carrier effect, lifetime prediction, and reliability become more important concepts for MOS transistors. In this paper, the degradation in the drain current and threshold voltage of P-MOS transistors are observed by operating the devices under voltage stress conditions. Using the observation results, the effect of hot-carriers was investigated statistically and a new statistical method for modeling was proposed as an alternative to those given in the literature. The linear regression method is used to estimate the power, Weibull, and logarithmic parameters, and …


The Effect Of Collector Doping On Inp-Based Double Heterojunction Bipolar Transistors, Serkan Topaloğlu, Jörn Driesen, Werner Prost, Franz Josef Tegude Jan 2006

The Effect Of Collector Doping On Inp-Based Double Heterojunction Bipolar Transistors, Serkan Topaloğlu, Jörn Driesen, Werner Prost, Franz Josef Tegude

Turkish Journal of Electrical Engineering and Computer Sciences

High current effects on double heterojunction bipolar transistor (DHBT) performance were investigated. Three DHBTs with different collector doping densities were grown and processed. DC and RF measurements were performed to evaluate the influence of collector doping and the related Kirk effect on HBT performance. In addition to these samples, the Kirk effect was proven on SHBTs and the delay of this effect on submicron HBTs was investigated.


An Adaptive Feedforward Amplifier Application For 5.8 Ghz, Engi̇n Kurt, Osman Palamutçuoğullari Jan 2006

An Adaptive Feedforward Amplifier Application For 5.8 Ghz, Engi̇n Kurt, Osman Palamutçuoğullari

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a 5.8 GHz power amplifier is linearized by an adaptive feedforward technique. A DSP-based control scheme is applied to reduce the intermodulation distortion of this amplifier. A two-tone test is used to verify the design.


Artificial Neural Design Of Microstrip Antennas, Nurhan Türker, Fi̇li̇z Güneş, Tülay Yildirim Jan 2006

Artificial Neural Design Of Microstrip Antennas, Nurhan Türker, Fi̇li̇z Güneş, Tülay Yildirim

Turkish Journal of Electrical Engineering and Computer Sciences

A general design procedure is suggested for microstrip antennas using artificial neural networks and this is demonstrated using rectangular patch geometry. In this design procedure, synthesis is defined as the forward side and then analysis as the reverse side of the problem. Worked examples are given using the most efficient materials.


Wind Power, Distributed Generation: New Challenges, New Solutions, Vladimiro Miranda Jan 2006

Wind Power, Distributed Generation: New Challenges, New Solutions, Vladimiro Miranda

Turkish Journal of Electrical Engineering and Computer Sciences

This paper discusses some issues related with the growing importance of wind power and in modern power systems and some challenges raised by the emergence of distributed generation, and how computational intelligence and other modern techniques have been able to provide valuable results in solving the new problems. It presents some solutions obtained with a number of computational intelligence techniques and their application to real cases.


Controlling Rail Potential Of Dc Supplied Rail Traction Systems, Mehmet Turan Söylemez, Süleyman Açikbaş, Adnan Kaypmaz Jan 2006

Controlling Rail Potential Of Dc Supplied Rail Traction Systems, Mehmet Turan Söylemez, Süleyman Açikbaş, Adnan Kaypmaz

Turkish Journal of Electrical Engineering and Computer Sciences

Most modern DC electrified mass transit systems use a totally floating earth as their grounding strategy. A well-known problem related with totally floating systems is that the touch potentials can be dangerously high. In order to reduce the voltages on rails, several devices exist. Most of these devices allow a direct connection to earth when a certain voltage threshold is exceeded. In this paper, the working principles of these devices are given and the effect of certain parameters related with these devices on the minimum achievable touch potentials is investigated.


The Journal Of Undergraduate Research: Volume 04 Jan 2006

The Journal Of Undergraduate Research: Volume 04

The Journal of Undergraduate Research

This is the complete issue of the South Dakota State University Journal of Undergraduate Research, Volume 4.


Economic Evaluation Of Integrating Biodiesel Production With A Dry Mill Ethanol Plant, Steven Bly Jan 2006

Economic Evaluation Of Integrating Biodiesel Production With A Dry Mill Ethanol Plant, Steven Bly

The Journal of Undergraduate Research

Biodiesei is produced by adding methyl ester products to diesel fuel. Base catalyzed transesterification of oil with methanol is the primary process used today. Current dry mill ethanol production facilities allow the com oil to pass through the process where it becomes part of the dried distiller's grain with solubles (DDGS), a lower valued feed co-product. This study evaluated the economic feasibility of integrating a biodiesel production facility with existing and/or new dry mill ethanol plants. The following methods for com oil separation were considered; hexane extraction of com oil from the dried distiller's grain stream, initial germ separation and …


Book Review: Digital Crime And Forensic Science In Cyberspace, Gary C. Kessler Jan 2006

Book Review: Digital Crime And Forensic Science In Cyberspace, Gary C. Kessler

Journal of Digital Forensics, Security and Law

This issue presents the first Book Review column for the JDFSL. It is an experiment to broaden the services that the journal provides to readers, so we are anxious to get your reaction. Is the column useful and interesting? Should we include more than one review per issue? Should we also review products? Do you have suggested books/products for review and/or do you want to write a review? All of this type of feedback -- and more -- is appreciated. Please feel free to send comments to Gary Kessler ([email protected]) or Glenn Dardick ([email protected]).


Alphaco: A Teaching Case On Information Technology Audit And Security, Hüseyin Tanriverdi, Joshua Bertsch, Jonathan Harrison, Po-Ling Hsiao, Ketan S. Mesuria, David Hendrawirawan Jan 2006

Alphaco: A Teaching Case On Information Technology Audit And Security, Hüseyin Tanriverdi, Joshua Bertsch, Jonathan Harrison, Po-Ling Hsiao, Ketan S. Mesuria, David Hendrawirawan

Journal of Digital Forensics, Security and Law

Recent regulations in the United States (U.S.) such as the Sarbanes-Oxley Act of 2002 require top management of a public firm to provide reasonable assurance that they institute internal controls that minimize risks over the firm’s operations and financial reporting. External auditors are required to attest to the management’s assertions over the effectiveness of those internal controls. As firms rely more on information technology (IT) in conducting business, they also become more vulnerable to IT related risks. IT is critical for initiating, recording, processing, summarizing and reporting accurate financial and non-financial data. Thus, understanding IT related risks and instituting internal …


Table Of Contents Jan 2006

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.


Designing A Data Warehouse For Cyber Crimes, Il-Yeol Song, John D. Maguire, Ki Jung Lee, Namyoun Choi, Xiaohua Hu, Peter Chen Jan 2006

Designing A Data Warehouse For Cyber Crimes, Il-Yeol Song, John D. Maguire, Ki Jung Lee, Namyoun Choi, Xiaohua Hu, Peter Chen

Journal of Digital Forensics, Security and Law

One of the greatest challenges facing modern society is the rising tide of cyber crimes. These crimes, since they rarely fit the model of conventional crimes, are difficult to investigate, hard to analyze, and difficult to prosecute. Collecting data in a unified framework is a mandatory step that will assist the investigator in sorting through the mountains of data. In this paper, we explore designing a dimensional model for a data warehouse that can be used in analyzing cyber crime data. We also present some interesting queries and the types of cyber crime analyses that can be performed based on …


A Forensic Log File Extraction Tool For Icq Instant Messaging Clients, Kim Morfitt, Craig Valli Jan 2006

A Forensic Log File Extraction Tool For Icq Instant Messaging Clients, Kim Morfitt, Craig Valli

Journal of Digital Forensics, Security and Law

Instant messenger programs such as ICQ are often used by hackers and criminals for illicit purposes and consequently the log files from such programs are of interest in a forensic investigation. This paper outlines research that has resulted in the development of a tool for the extraction of ICQ log file entries. Detailed reconstruction of data from log files was achieved with a number of different ICQ software. There are several limitations with the current design including timestamp information not adjusted for the time zone, data could be altered, and conversations must be manually reconstructed. Future research will aim to …


The Design Of An Undergraduate Degree Program In Computer & Digital Forensics, Gary C. Kessler, Michael E. Schirling Jan 2006

The Design Of An Undergraduate Degree Program In Computer & Digital Forensics, Gary C. Kessler, Michael E. Schirling

Journal of Digital Forensics, Security and Law

Champlain College formally started an undergraduate degree program in Computer & Digital Forensics in 2003. The underlying goals were that the program be multidisciplinary, bringing together the law, computer technology, and the basics of digital investigations; would be available as on online and oncampus offering; and would have a process-oriented focus. Success of this program has largely been due to working closely with practitioners, maintaining activity in events related to both industry and academia, and flexibility to respond to ever-changing needs. This paper provides an overview of how this program was conceived, developed, and implemented; its evolution over time; and …


The Role Of Power And Negotiation In Online Deception, Chad Albrecht, Conan C. Albrecht, Jonathan Wareham, Paul Fox Jan 2006

The Role Of Power And Negotiation In Online Deception, Chad Albrecht, Conan C. Albrecht, Jonathan Wareham, Paul Fox

Journal of Digital Forensics, Security and Law

The purpose of this paper is to advance theoretical understanding of the important role of both power and negotiation during online deception. By so doing, the paper provides insight into the relationship between perpetrator and victim in Internet fraud. The growing prevalence of Internet Fraud continues to be a burden to both society and individuals. In an attempt to better understand Internet fraud and online deception, this article attempts to build an interactive model, based upon the dimensions of power and negotiation from the management and psychology literature. Using the model presented, the article examines the effects of the Internet …


A Curriculum For Teaching Information Technology Investigative Techniques For Auditors, Grover S. Kearns Jan 2006

A Curriculum For Teaching Information Technology Investigative Techniques For Auditors, Grover S. Kearns

Journal of Digital Forensics, Security and Law

Recent prosecutions of highly publicized white-collar crimes combined with public outrage have resulted in heightened regulation of financial reporting and greater emphasis on systems of internal control. Because both white-collar and cybercrimes are usually perpetrated through computers, internal and external auditors’ knowledge of information technology (IT) is now more vital than ever. However, preserving digital evidence and investigative techniques, which can be essential to fraud examinations, are not skills frequently taught in accounting programs and instruction in the use of computer assisted auditing tools and techniques – applications that might uncover fraudulent activity – is limited. Only a few university-level …


Development Of A National Repository Of Digital Forensic Intelligence, Mark Weiser, David P. Biros, Greg Mosier Jan 2006

Development Of A National Repository Of Digital Forensic Intelligence, Mark Weiser, David P. Biros, Greg Mosier

Journal of Digital Forensics, Security and Law

Many people do all of their banking online, we and our children communicate with peers through computer systems, and there are many jobs that require near continuous interaction with computer systems. Criminals, however, are also “connected”, and our online interaction provides them a conduit into our information like never before. Our credit card numbers and other fiscal information are at risk, our children's personal information is exposed to the world, and our professional reputations are on the line.

The discipline of Digital Forensics in law enforcement agencies around the nation and world has grown to match the increased risk and …


Electronic Data Discovery: Integrating Due Process Into Cyber Forensic Practice, John W. Bagby, John C. Ruhnka Jan 2006

Electronic Data Discovery: Integrating Due Process Into Cyber Forensic Practice, John W. Bagby, John C. Ruhnka

Journal of Digital Forensics, Security and Law

Most organizations and government agencies regularly become engaged in litigation with suppliers, customers, clients, employees, competitors, shareholders, prosecutors or regulatory agencies that nearly assures the need to organize, retain, find and produce business records and correspondence, emails, accounting records or other data relevant to disputed issues. This article discusses some high visibility cases that constrain how metadata and content is routinely made available to opposing parties in civil litigation, to prosecutors in criminal prosecutions and to agency staff in regulatory enforcement litigation. Public policy, as implemented in the rules of evidence and pretrial discovery, restrict electronic data discovery (EDD) as …


Forensic Tools For Mobile Phone Subscriber Identity Modules, Wayne Jansen, Rick Ayers Jan 2006

Forensic Tools For Mobile Phone Subscriber Identity Modules, Wayne Jansen, Rick Ayers

Journal of Digital Forensics, Security and Law

Mobile phones and other handheld devices incorporating cellular capabilities, such as Personal Digital Assistants, are ubiquitous. Besides placing calls, these devices allow users to perform other useful tasks, including text messaging and phonebook entry management. When cell phones and cellular devices are involved in a crime or other incident, forensic specialists require tools that allow the proper retrieval and speedy examination of data present on the device. For devices conforming to the Global System for Mobile Communications (GSM) standards, certain data such as dialed numbers, text messages, and phonebook entries are maintained on a Subscriber Identity Module (SIM). This paper …


Gis And 3d Analysis Applied To Sea Turtle Mortalities And Navigation Channel Dredging, Bradley A. Shellito, Keith B. Lockwood Jan 2006

Gis And 3d Analysis Applied To Sea Turtle Mortalities And Navigation Channel Dredging, Bradley A. Shellito, Keith B. Lockwood

Virginia Journal of Science

Between 2000 and 2003 there were an increased number of documented sea turtle mortalities related to hopper dredging in the channels of the Chesapeake Bay. A pilot study was undertaken to create a bathymetric surface and three-dimensional model of the Cape Henry Channel using Geographic Information Systems (GIS) as a visualization tool to examine sea turtle mortalities in relation to the dredging. In Fall 2003, the US Army Corps of Engineers dredged the Thimble Shoals Federal Navigation Channel, and a more refined model was developed using this data. This project examines the growing concerns over sea turtle mortality rates and …


Bs News Jan 2006

Bs News

Building Services Engineering

No abstract provided.


A Corpus-Based Concatenative Speech Synthesis System For Turkish, Haşi̇m Sak, Tunga Güngör, Yaşar Safkan Jan 2006

A Corpus-Based Concatenative Speech Synthesis System For Turkish, Haşi̇m Sak, Tunga Güngör, Yaşar Safkan

Turkish Journal of Electrical Engineering and Computer Sciences

Speech synthesis is the process of converting written text into machine-generated synthetic speech. Concatenative speech synthesis systems form utterances by concatenating pre-recorded speech units. Corpus-based methods use a large inventory to select the units to be concatenated. In this paper, we design and develop an intelligible and natural sounding corpus-based concatenative speech synthesis system for the Turkish language. The implemented system contains a front-end comprised of text analysis, phonetic analysis, and optional use of transplanted prosody. The unit selection algorithm is based on commonly used Viterbi decoding algorithm of the best-path in the network of the speech units using spectral …


An Ann Based Approach To Improve The Distance Relaying Algorithm, Hassan Khorashadi Zadeh, Zuyi Li Jan 2006

An Ann Based Approach To Improve The Distance Relaying Algorithm, Hassan Khorashadi Zadeh, Zuyi Li

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents an artificial neural network- (ANN) based approach to improve the performance of the distance relaying algorithm. The proposed distance relay uses magnitudes of voltages and currents as input signals to find fault locations. In this approach, an ANN has been included in the protection algorithm as an extension of the existing methods, which improves the reliability of the protection operation. The design procedure of the proposed relay is presented in detail. Simulation studies are performed and the influence of changing system parameters, such as fault resistance and source impedance, is studied. Performance studies show that the proposed …


Sturm-Liouville Equation: The Bridge Between Eigenvalue And Green's Function Problems, Levent Sevgi̇ Jan 2006

Sturm-Liouville Equation: The Bridge Between Eigenvalue And Green's Function Problems, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

This article is intended as an educational aid and discusses guided wave propagation problems that are modeled via the Sturm-Liouville equation in electromagnetics. The bridge between source-free (eigenvalue) and source-driven (Green's function) problems that are represented by the same Sturm-Liouville equation is emphasized. The presentation focuses on representation of an arbitrary source from the features (eigenfunctions) of the problem geometry and extraction of the eigenvalues of a problem from propagation characteristics (Green's function) on a canonical problem; a homogeneously filled parallel plate waveguide with non-penetrable boundaries


A Pi Controller Based On Gain-Scheduling For Synchronous Generator, Alireza Sedaghati Jan 2006

A Pi Controller Based On Gain-Scheduling For Synchronous Generator, Alireza Sedaghati

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper a gain- scheduling scheme of a proportional integral (GSPI) controller is proposed for a synchronous generator. In presented scheme, both proportional and integral gains are allowed to vary within a predetermined range. In order to validate the effectiveness of GSPI controller, simulation studies for a single-machine infinite bus power system are used .The results verify improved performance of GSPI controller comparing to conventional AVR under various operating conditions.


State-Space Synthesis Of Current-Mode First-Order Log-Domain Filters, Ali̇ Kirçay, Uğur Çam Jan 2006

State-Space Synthesis Of Current-Mode First-Order Log-Domain Filters, Ali̇ Kirçay, Uğur Çam

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes current-mode first-order log-domain filters, which are systematically derived using the state-space synthesis procedure. First-order low-pass, high-pass, and all-pass responses are obtained with different circuit types. The filter circuits have very simple structures, since they use only bipolar junction transistors (BJTs) and a grounded capacitor. They can be electronically tuned by changing an external current. The filters have a greater bandwidth due to inherently current-mode and log-domain operation. PSPICE simulations are given to confirm the theoretical analysis.


Electrical And Computer Engineering Education In The 21^{St} Century: Issues, Perspectives And Challenges, Levent Sevgi̇ Jan 2006

Electrical And Computer Engineering Education In The 21^{St} Century: Issues, Perspectives And Challenges, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Infusing Technical Communication And Teamwork Within The Ece Curriculum, By April Kedrowicz, Sundy Watanabe, Damon Hall, Cynthia Furse Jan 2006

Infusing Technical Communication And Teamwork Within The Ece Curriculum, By April Kedrowicz, Sundy Watanabe, Damon Hall, Cynthia Furse

Turkish Journal of Electrical Engineering and Computer Sciences

This paper highlights a unique approach to infusing formal training and practice in oral and written communication and teamwork development in the Department of Electrical and Computer Engineering (ECE) at the University of Utah. Faculty and graduate (Ph.D.) students from the College of Humanities have teamed up with faculty from engineering to develop communication and teamwork instruction that is integrated into the existing engineering curriculum. These skills are used as a vehicle to provide better understanding of engineering concepts and their applications.


Secure Digital Communication Using Chaotic Symbolic Dynamics, Ajeesh P. Kurian, Sadasivan Puthusserypady Jan 2006

Secure Digital Communication Using Chaotic Symbolic Dynamics, Ajeesh P. Kurian, Sadasivan Puthusserypady

Turkish Journal of Electrical Engineering and Computer Sciences

One of the major hurdles in implementing chaotic communication schemes is the synchronization of chaotic systems. For the last two decades, numerous contributions of varying successes have been made by researchers from different disciplines for the synchronization of chaotic systems. Symbolic dynamics based synchronization method is shown to be capable of providing high quality synchronization (HQS), which is essential for reliable communication. In this work, using this method, a secure digital communication system is proposed. The well known piece-wise linear 1-D map such as tent map and Bernoulli shift map are used for this study. Since the information is dynamically …


Development And Delivery Of Coursework: The Legal/Regulatory/Policy Environment Of Cyberforensics, John W. Bagby, John C. Ruhnka Jan 2006

Development And Delivery Of Coursework: The Legal/Regulatory/Policy Environment Of Cyberforensics, John W. Bagby, John C. Ruhnka

Journal of Digital Forensics, Security and Law

This paper describes a cyber-forensics course that integrates important public policy and legal issues as well as relevant forensic techniques. Cyber-forensics refers to the amalgam of multi-disciplinary activities involved in the identification, gathering, handling, custody, use and security of electronic files and records, involving expertise from the forensic domain, and which produces evidence useful in the proof of facts for both commercial and legal activities. The legal and regulatory environment in which electronic discovery takes place is of critical importance to cyber-forensics experts because the legal process imposes both constraints and opportunities for the effective use of evidence gathered through …