Computer Engineering Commons^™

Technology Corner Automated Data Extraction Using Facebook, Nick V. Flor

Journal of Digital Forensics, Security and Law

Because of Facebook’s popularity, law enforcement agents often use it as a key source of evidence. But like many user digital trails, there can be a large amount of data to extract for analysis. In this paper, we explore the basics of extracting data programmatically from a user’s Facebook via a Web app. A data extraction app requests data using the Facebook Graph API, and Facebook returns a JSON object containing the data. Before an app can access a user’s Facebook data, the user must log into Facebook and give permission. Thus, this approach is limited to situations where users …

Book Review: Mastering Windows Network Forensics And Investigation, 2/E, John C. Ebert

Journal of Digital Forensics, Security and Law

The book is available as a paperback and e-book. The e-book versions allow you to preview several chapters at any of a number of online vendors. The e-book prices vary from the same as the soft cover version ($59.99) to about $38.99. Some of the vendor's e-books retain the color illustrations found in the print version, but others produce them in grey scale, so you might want to look out for that. The book is divided into four parts (17 chapters) plus two appendices.

I am compelled to give the book illustrations a highly unfavorable assessment regarding their readability qualities. …

Column: Analysis Of Digital Traces, Fred Cohen

Journal of Digital Forensics, Security and Law

In part 1 of this series (Cohen, 2011a), Analysis of digital traces is a foundational process by which the examiner, typically using computer software tools, comes to understand and answer basic questions regarding digital traces.

An Australian Perspective On The Challenges For Computer And Network Security For Novice Endusers, Patryk Szewczyk

Journal of Digital Forensics, Security and Law

It is common for end-users to have difficulty in using computer or network security appropriately and thus have often been ridiculed when misinterpreting instructions or procedures. This discussion paper details the outcomes of research undertaken over the past six years on why security is overly complex for endusers. The results indicate that multiple issues may render end-users vulnerable to security threats and that there is no single solution to address these problems. Studies on a small group of senior citizens has shown that educational seminars can be beneficial in ensuring that simple security aspects are understood and used appropriately.

Automated Identification And Reconstruction Of Youtube Video Access, Jonathan Patterson, Christopher Hargreaves

Journal of Digital Forensics, Security and Law

YouTube is one of the most popular video-sharing websites on the Internet, allowing users to upload, view and share videos with other users all over the world. YouTube contains many different types of videos, from homemade sketches to instructional and educational tutorials, and therefore attracts a wide variety of users with different interests. The majority of YouTube visits are perfectly innocent, but there may be circumstances where YouTube video access is related to a digital investigation, e.g. viewing instructional videos on how to perform potentially unlawful actions or how to make unlawful articles. When a user accesses a YouTube video …

Book Review: System Forensics, Investigation, And Response, Nate Keith

Journal of Digital Forensics, Security and Law

I recently expressed an interest to a respected colleague in finding a way to “give back” to the forensic community. He suggested writing a review for a text he recently received and provide feedback to the community. It is my intent to present an objective analysis of System Forensics, Investigation, and Response.

Identifying Trace Evidence From Target-Specific Data Wiping Application Software, Gregory H. Carlton, Gary C. Kessler

Journal of Digital Forensics, Security and Law

One area of particular concern for computer forensics examiners involves situations in which someone utilized software applications to destroy evidence. There are products available in the marketplace that are relatively inexpensive and advertised as being able to destroy targeted portions of data stored within a computer system. This study was undertaken to analyze a subset of these tools in order to identify trace evidence, if any, left behind on disk media after executing these applications. We evaluated five Windows 7 compatible software products whose advertised features include the ability for users to wipe targeted files, folders, or evidence of selected …

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

Technology Corner: A Regular Expression Training App, Nick V. Flor

Journal of Digital Forensics, Security and Law

Regular expressions enable digital forensic analysts to find information in files. The best way for an analyst to become proficient in writing regular expressions is to practice. This paper presents the code for an app that allows an analyst to practice writing regular expressions.

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

Extraction Of Electronic Evidence From Voip: Identification & Analysis Of Digital Speech, David Irwin, Arek Dadej, Jill Slay

Journal of Digital Forensics, Security and Law

The Voice over Internet Protocol (VoIP) is increasing in popularity as a cost effective and efficient means of making telephone calls via the Internet. However, VoIP may also be an attractive method of communication to criminals as their true identity may be hidden and voice and video communications are encrypted as they are deployed across the Internet. This produces a new set of challenges for forensic analysts compared with traditional wire-tapping of the Public Switched Telephone Network (PSTN) infrastructure, which is not applicable to VoIP. Therefore, other methods of recovering electronic evidence from VoIP are required. This research investigates the …

Book Review: Dispute Resolution And E-Discovery, Milton Luoma

Journal of Digital Forensics, Security and Law

As is apparent from its title, this book tackles two very current and difficult legal issues – electronic discovery and dispute resolution. The authors tie the two legal concepts together in an effort to provide litigants and practitioners a less expensive and less time consuming alternative than is typically the case with traditional litigation and court proceedings. By including electronic discovery in the discussions, the authors recognize the importance and significance of electronic discovery in mediation and arbitration as it is in traditional litigation.

On The Development Of A Digital Forensics Curriculum, Manghui Tu, Dianxiang Xu, Samsuddin Wira, Cristian Balan, Kyle Cronin

Journal of Digital Forensics, Security and Law

Computer Crime and computer related incidents continue their prevalence and frequency, resulting in losses approaching billions of dollars. To fight against these crimes and frauds, it is urgent to develop digital forensics education programs to train a suitable workforce that can effectively investigate computer crimes and incidents. There is presently no standard to guide the design of digital forensics curriculum for an academic program. In this research, previous work on digital forensics curriculum design and existing education programs are thoroughly investigated. Both digital forensics educators and practitioners were surveyed and results were analyzed to determine the industry and law enforcement …

The Science Of Digital Forensics: Recovery Of Data From Overwritten Areas Of Magnetic Media, Fred Cohen

Journal of Digital Forensics, Security and Law

The first time I encountered data loss and recovery effects of magnetic memory was as a night and weekend computer operator for the computer science department of Carnegie-Mellon University in the 1973-1974 time frame. Part of my job involved dealing directly with outages and failures associated with magnetic memory components used in what, at the time, were large computer systems. On occasions, portions of magnetic core memory or disk drives would encounter various failure modes and the systems using these devices would have to be reconfigured to operate without the failed components until repair personnel could come in to repair …

Automatic Crash Recovery: Internet Explorer's Black Box, John Moran, Douglas Orr

Journal of Digital Forensics, Security and Law

A good portion of today's investigations include, at least in part, an examination of the user's web history. Although it has lost ground over the past several years, Microsoft's Internet Explorer still accounts for a large portion of the web browser market share. Most users are now aware that Internet Explorer will save browsing history, user names, passwords and form history. Consequently some users seek to eliminate these artifacts, leaving behind less evidence for examiners to discover during investigations. However, most users, and probably a good portion of examiners are unaware Automatic Crash Recovery can leave a gold mine of …

Book Review: The Software Ip Detective's Handbook: Measurement, Comparison, And Infringement Detections, Diane Barrett

Journal of Digital Forensics, Security and Law

Do not the book title fool you into thinking that the book is only for those looking to detect software infringement detection. It is a comprehensive look at software intellectual property. The book covers a wide range of topics and has something to offer for just about everyone from lawyers to programmers.

“Preemptive Suppression” – Judges Claim The Right To Find Digital Evidence Inadmissible Before It Is Even Discovered, Bob Simpson

Journal of Digital Forensics, Security and Law

Vermont state prosecutors have asked the Vermont Supreme Court to end a state trial judge’s practice of attaching conditions to computer warrants. The Vermont judge’s conditions are drawn from five conditions established in the 2009 decision of the 9th Circuit Court of Appeals in the Comprehensive Drug Testing, Inc. case (CDT II). This is the first time the validity of the “CDT conditions” will be decided by a state court of final jurisdiction in the United States

Modeling And Control Of Discrete Event Systems Using Finite State Machines With Variables And Their Applications In Power Grids, Junhui Zhao, Le Yi Wang, Zhong Chen, Feng Lin, Hongwei Zhang

Electrical & Computer Engineering and Computer Science Faculty Publications

Control theories for discrete event systems modeled as finite state machines have been well developed to address various fundamental control issues. However, finite state machine model has long suffered from the problem of state explosion that renders it unsuitable for some practical applications. In an attempt to mitigate the state explosion problem, we propose an efficient representation that appends finite sets of variables to finite state machines in modeling discrete event systems. We also present the control synthesis techniques for such finite state machines with variables (FSMwV). We first present our notion and means of control under this representation. We …

Characterizing Metal-Insulator-Transition (Mit) Phase Change Materials (Pcm) For Rf And Dc Micro-Switching Elements, Brent L. Danner, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

Metal-insulator transition (MIT) phase-change materials (PCM) are material compounds that have the ability to be either conductors or insulators depending on external stimuli. A micromachined test structure for applying external electric fields across MIT wire segments was designed and fabricated. Using this novel test structure, Germanium Telluride (GeTe) and Vanadium Oxide (VOx) were successfully transitioned from a conductor to an insulator. The resistivity of the GeTe wire segments increased three to five orders of magnitude with ∼40 V applied to the parallel plates of the test structure. The VOx wires exhibited an order of magnitude transition in resistivity with ∼20 …

Continuous Time-Varying Biasing Approach For Spectrally Tunable Infrared Detectors, Woo-Yong Jang, Majeed M. Hayat, Payman Zarkesh-Ha, Sanjay Krishna

Electrical and Computer Engineering Faculty Research and Publications

In a recently demonstrated algorithmic spectral-tuning technique by Jang et al. [Opt. Express 19, 19454-19472, (2011)], the reconstruction of an object’s emissivity at an arbitrarily specified spectral window of interest in the long-wave infrared region was achieved. The technique relied upon forming a weighted superposition of a series of photocurrents from a quantum dots-in-a-well (DWELL) photodetector operated at discrete static biases that were applied serially. Here, the technique is generalized such that a continuously varying biasing voltage is employed over an extended acquisition time, in place using a series of fixed biases over each sub-acquisition time, which totally …

A New Ensemble Learning Method For Temporal Pattern Identification, Wenjing Zhang, Xin Feng

Electrical and Computer Engineering Faculty Research and Publications

In this paper we present a method for identification of temporal patterns predictive of significant events in a dynamic data system. A new hybrid model using Reconstructed Phase Space (MRPS) and Hidden Markov Model (HMM) is applied to identify temporal patterns. This method constructs phase space embedding by using individual embedding of each variable sequences. We also employ Hidden Markov Models (HMM) to the multivariate sequence data to categorize multi-dimensional data into three states, e.g. normal, patterns and events. A support vector machine optimization method is used to search an optimal classifier to identify temporal patterns that are predictive of …

New Perspective On Passively Quenched Single Photon Avalanche Diodes: Effect Of Feedback On Impact Ionization, David A. Ramirez, Majeed M. Hayat, Graham J. Rees, Xudong Jiang, Mark A. Itzler

Electrical and Computer Engineering Faculty Research and Publications

Single-photon avalanche diodes (SPADs) are primary devices in photon counting systems used in quantum cryptography, time resolved spectroscopy and photon counting optical communication. SPADs convert each photo-generated electron hole pair to a measurable current via an avalanche of impact ionizations. In this paper, a stochastically self-regulating avalanche model for passively quenched SPADs is presented. The model predicts, in qualitative agreement with experiments, three important phenomena that traditional models are unable to predict. These are: (1) an oscillatory behavior of the persistent avalanche current; (2) an exponential (memoryless) decay of the probability density function of the stochastic quenching time of the …

A Suspended Nanogap Formed By Field-Induced Atomically Sharp Tips, Jun Hyun Han, Kyung Song, Shankar Radhakrishnan, Sang Ho Oh, Chung Hoon Lee

Electrical and Computer Engineering Faculty Research and Publications

A sub-nanometer scale suspended gap (nanogap) defined by electric field-induced atomically sharp metallic tips is presented. A strong local electric field (>109 V=m) across micro/nanomachined tips facing each other causes the metal ion migration in the form of dendrite-like growth at the cathode. The nanogap is fully isolated from the substrate eliminating growth mechanisms that involve substrate interactions. The proposed mechanism of ion transportation is verified using real-time imaging of the metal ion transportation using an in situ biasing in transmission electron microscope (TEM). The configuration of the micro/nanomachined suspended tips allows nanostructure growth of a wide variety of …

A Very Robust Algan/Gan Hemt Technology To High Forward Gate Bias And Current, Bradley D. Christiansen, Eric R. Heller, Ronald A. Coutu Jr., Ramakrishna Vetury, Jeffrey B. Shealy

Electrical and Computer Engineering Faculty Research and Publications

Reports to date of GaN HEMTs subjected to forward gate bias stress include varied extents of degradation. We report an extremely robust GaN HEMT technology that survived—contrary to conventional wisdom—high forward gate bias (+6 V) and current (>1.8 A/mm) for >17.5 hours exhibiting only a slight change in gate diode characteristic, little decrease in maximum drain current, with only a 0.1 V positive threshold voltage shift, and, remarkably, a persisting breakdown voltage exceeding 200 V.

A Mems Photoacoustic Detector Of Terahertz Radiation For Chemical Sensing, Nathan Glauvitz, S. Blazevic, Ronald A. Coutu Jr., Michael Kistler, Ivan R. Medvedev, Douglas T. Petkie

Electrical and Computer Engineering Faculty Research and Publications

A piezoelectric Microelectromechanical system (MEMS) cantilever pressure sensor was designed, modeled, fabricated, and tested for sensing the photoacoustic response of gases to terahertz (THz) radiation. The sensing layers were comprised of three thin films; a lead zirconate titanate (PZT) piezoelectric layer sandwiched between two metal contact layers. The sensor materials were deposited on the silicon device layer of a silicon-on-insulator (SOI) wafer, which formed the physical structure of the cantilever. To release the cantilever, a hole was etched through the backside of the wafer and the buried oxide was removed with hydrofluoric acid. Devices were then tested in a custom …

Multiplication Theory For Dynamically Biased Avalanche Photodiodes: New Limits For Gain Bandwidth Product, Majeed M. Hayat, David A. Ramirez

Electrical and Computer Engineering Faculty Research and Publications

Novel theory is developed for the avalanche multiplication process in avalanche photodiodes (APDs) under time-varying reverse-biasing conditions. Integral equations are derived characterizing the statistics of the multiplication factor and the impulse-response function of APDs, as well as their breakdown probability, all under the assumption that the electric field driving the avalanche process is time varying and spatially nonuniform. Numerical calculations generated by the model predict that by using a bit-synchronous sinusoidal biasing scheme to operate the APD in an optical receiver, the pulse-integrated gain-bandwidth product can be improved by a factor of 5 compared to the same APD operating under …

Measurement And Modeling Of Passive Surface Mount Devices On Fr4 Substrates, Rahulkumar Sadanand Koche

Dissertations and Theses

Passive components like resistors, capacitors and inductors are used in every electronic system. These are the very basic components which affect the system performance at higher frequencies and it is necessary to understand and model the behavior of these components in a very accurate manner. This work focuses on utilizing Printed Circuit Board (PCB) test boards, or fixtures, made of FR4 for characterizing Surface Mount Device (SMD) components. Agilent's Advanced Design System (ADS) microwave circuit simulation software was used for designing the microstrip transmission lines as well as for generating the layout for manufacturing of the PCB. SMD resistors, capacitors …

New Change Impact Factor Estimation In Software Development, Murat Kahraman Güngör, Ersi̇n Elbaşi, James Walter Fawcett

Turkish Journal of Electrical Engineering and Computer Sciences

Change in software is always an essential part of software development and maintenance. Estimating a proposed change's effect on the later phases of the development helps project managers and developers with decision-making and predicting future progress. During development, on some occasions, speedy solutions are necessary to meet project schedules. Such quick changes may lead to major quality flaws in the long term, even though they solve local problems in the short term. Controlled management of change is achieved by being able to estimate the impact of changes. In this paper, we propose a new change impact factor estimation and present …

Optimization Of Pilot Tones Using Differential Evolution Algorithm In Mimo-Ofdm Systems, Muhammet Nuri̇ Seyman, Necmi̇ Taşpinar

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, we propose a differential evolution (DE) algorithm for optimizing the placement and power of the pilot tones that are utilized by a least square (LS) algorithm for channel estimation in multiple-input and multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems. Computer simulations demonstrated that the performance of the LS algorithm was increased by optimizing the pilot tones with the DE algorithm instead of locating them orthogonally. We used the upper bound of the mean square error (MSE) as a fitness function of the DE algorithm for optimization tasks. With the use of an upper bound, it is not necessary …

An Improved Fastslam Framework Using Soft Computing, Ramazan Havangi, Mohammad Ali Nekoui, Mohammad Teshnehlab

Turkish Journal of Electrical Engineering and Computer Sciences

FastSLAM is a framework for simultaneous localization and mapping (SLAM) using a Rao-Blackwellized particle filter. However, FastSLAM degenerates over time. This degeneracy is due to the fact that a particle set estimating the pose of the robot loses its diversity. One of the main reasons for losing particle diversity in FastSLAM is sample impoverishment. In this case, most of the particle weights are insignificant. Another problem of FastSLAM relates to the design of an extended Kalman filter (EKF) for the landmark position's estimation. The performance of the EKF and the quality of the estimation depend heavily on correct a priori …