Engineering Commons^™

Observed Superspin-Glass Behavior In Ni0.5zn0.5fe2o4 Nanoparticles, Antony Adair

Open Access Theses & Dissertations

In this investigation we seek to identify the magnetic behavior of Ni0.5Zn0.5Fe2O4 nanoparticles though AC-susceptibility and DC-magnetization measurements. Powder x-ray diffraction was performed to determine the purity and average diameter ( ~ 9nm) of the particles. Aditionally, structure was confirmed by comparison through the International Centre for Diffraction Data's Powder Diffraction File [52] (PDF # 08-0234).

Zero-field cooled and field cooled DC magnetization measurements (bifurcation and blocking temperature), as well as M(H) hysteresis (below and above the blocking temperature) lead us to initially suggest that the material may in fact be superparamagnetic. However, further investigation of the real AC susceptibility …

Silica Removal From Brine By Using Ion Exchange, Carlos R. Acevedo

Open Access Theses & Dissertations

Local governments have been forced to look for additional water sources to satisfy the ever increasing demand for fresh water. Very often, the new water sources such as the underground water in continental territories have high salt content. Currently, reverse osmosis technology (RO) is one of the most common processes for water desalination. However, this process is limited by high silica and salt concentrations in water. At high concentrations silica clogs the membranes used in the RO process, reducing their life and increasing operational costs. In this study, quaternary ammonium resins and sulfonic acid resins were used to remove silica …

Multi-Objective Network Reliability Optimization Using Evolutionary Algorithms, Franciso Oswaldo Aguirre

Open Access Theses & Dissertations

This work presents a new multiple objective evolutionary algorithm to solve three well known network reliability allocation problems considering different conflicting objectives to be optimized simultaneously. The new algorithm is applied in the design of a telecommunication network that is formed for several stations or nodes interconnected by telecommunication links or paths. The problem presented in this work involves finding which links to activate in order to obtain connectivity in the nodes. The number of nodes that need to be connected depends of the case that is being evaluated. The three network reliability problems considered are: all-terminal, k-terminal, and two-terminal. …

Estimating Variation In Stiffness And Volume Change Of Clays From Geochemical And Index Properties, Cynthia Roxanna Zuniga

Open Access Theses & Dissertations

Clayey soils from six different locations in Texas were analyzed and evaluated with respect to their expansion and shrinkage and change in stiffness associated with moisture content variation. These soils consist of five high plasticity-index (PI) clays (PI greater than 25) and one low-PI clay (PI = 17). The behavior of the clays changes dramatically with moisture content fluctuation, thus causing stiffness and volume changes throughout the year. Total or differential volume movements caused by swell or shrinkage strains of expansive soils and reduction in modulus can exert enough pressure to damage the pavements and cause maintenance problems.

The intent …

Semi-Automated Frame Transformations Using Fft Analysis On 2-D Images, Francisco Javier Osuna

Open Access Theses & Dissertations

Cassini entered Saturn's orbit on July 1, 2004 beginning a four-year exploration of Saturn. In 2008 the mission was extended, and Cassini continues to collect and transmit images and data collected during its mission. In order to accurately interpret images, it is necessary to know the location and orientation of the camera provided the field of view when the image was collected. While the mission managers provide initial estimates of this orientation, scientific analysis requires better estimates than the initial data provided. Navigation is a process for improving the estimation of the true camera pointing vector as determined by features …

Transition Metal Catalysts For Hydrodesulfurization Reactions Applied To Petroleum Industry, Brenda Torres

Open Access Theses & Dissertations

Catalysis plays a fundamental role in petroleum refining and basic petrochemical industries creating new routes in the development of industrial processes. Moreover, catalysis has become indispensable to the solution of environmental pollution problems and therefore on public health. World wide concerns for preservation of the environment has motivated the development of "Green" catalyst based technologies, to achieve a better utilization of petroleum resources and demands for cleaner transportation fuels. These environmental concerns have led to increasingly drastic regulations on sulfur, nitrogen and aromatics content in fuels. Sulfur content in the motor and diesel fuels is continuously reduced by regulations to …

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

Online Child Sexual Abuse: The French Response, Mohamed Chawki

Journal of Digital Forensics, Security and Law

Online child sexual abuse is an increasingly visible problem in society today. The introduction, growth and utilization of information and telecommunication technologies (ICTs) have been accompanied by an increase in illegal activities. With respect to cyberspace the Internet is an attractive environment to sex offenders. In addition to giving them greater access to minors, extending their reach from a limited geographical area to victims all around the world, it allows criminals to alter or conceal their identities. Sexual predators, stalkers, child pornographers and child traffickers can use various concealment techniques to make it more difficult for investigators to identify them …

Correlating Orphaned Windows Registry Data Structures, Damir Kahvedžić, Tahar Kechadi

Journal of Digital Forensics, Security and Law

Recently, it has been shown that deleted entries of the Microsoft Windows registry (keys) may still reside in the system files once the entries have been deleted from the active database. Investigating the complete keys in context may be extremely important from both a Forensic Investigation point of view and a legal point of view where a lack of context can bring doubt to an argument. In this paper we formalise the registry behaviour and show how a retrieved value may not maintain a relation to the part of the registry it belonged to and hence lose that context. We …

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

Continuous Fraud Detection In Enterprise Systems Through Audit Trail Analysis, Peter J. Best, Pall Rikhardsson, Mark Toleman

Journal of Digital Forensics, Security and Law

Enterprise systems, real time recording and real time reporting pose new and significant challenges to the accounting and auditing professions. This includes developing methods and tools for continuous assurance and fraud detection. In this paper we propose a methodology for continuous fraud detection that exploits security audit logs, changes in master records and accounting audit trails in enterprise systems. The steps in this process are: (1) threat monitoringsurveillance of security audit logs for ‘red flags’, (2) automated extraction and analysis of data from audit trails, and (3) using forensic investigation techniques to determine whether a fraud has actually occurred. We …

A Synopsis Of Proposed Data Protection Legislation In Sa, Francis S. Cronjé

Journal of Digital Forensics, Security and Law

Privacy International1 made the following statement regarding South Africa’s financial sector in its 2005 world survey: “South Africa has a well-developed financial system and banking infrastructure. Despite the sophistication of the financial sector, the privacy of financial information is weakly regulated by a code of conduct for banks issued by the Banking Council.” This extract highlights some of the problems South Africa are experiencing with its current status on privacy as viewed from an International perspective. In recent years the International society has stepped up its efforts in creating a global village wherein the individual could be assured of having …

Bluetooth Hacking: A Case Study, Dennis Browning, Gary C. Kessler

Journal of Digital Forensics, Security and Law

This paper describes a student project examining mechanisms with which to attack Bluetooth-enabled devices. The paper briefly describes the protocol architecture of Bluetooth and the Java interface that programmers can use to connect to Bluetooth communication services. Several types of attacks are described, along with a detailed example of two attack tools, Bloover II and BT Info.

Detection Of Steganography-Producing Software Artifacts On Crime-Related Seized Computers, Asawaree Kulkarni, James Goldman, Brad Nabholz, William Eyre

Journal of Digital Forensics, Security and Law

Steganography is the art and science of hiding information within information so that an observer does not know that communication is taking place. Bad actors passing information using steganography are of concern to the national security establishment and law enforcement. An attempt was made to determine if steganography was being used by criminals to communicate information. Web crawling technology was used and images were downloaded from Web sites that were considered as likely candidates for containing information hidden using steganographic techniques. A detection tool was used to analyze these images. The research failed to demonstrate that steganography was prevalent on …

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

Prevention Is Better Than Prosecution: Deepening The Defence Against Cyber Crime, Jacqueline Fick

Journal of Digital Forensics, Security and Law

In the paper the author proposes that effectively and efficiently addressing cyber crime requires a shift in paradigm. For businesses and government departments alike the focus should be on prevention, rather than the prosecution of cyber criminals. The Defence in Depth strategy poses a practical solution for achieving Information Assurance in today’s highly networked environments. In a world where “absolute security” is an unachievable goal, the concept of Information Assurance poses significant benefits to securing one of an organization’s most valuable assets: Information. It will be argued that the approach of achieving Information Assurance within an organisation, coupled with the …

To License Or Not To License Revisited: An Examination Of State Statutes Regarding Private Investigators And Digital Examiners, Thomas Lonardo, Doug White, Alan Rea

Journal of Digital Forensics, Security and Law

In this update to the previous year's study, the authors examine statutes that regulate, license, and enforce investigative functions in each US state. After identification and review of Private Investigator licensing requirements, the authors find that very few state statutes explicitly differentiate between Private Investigators and Digital Examiners. After contacting all state agencies the authors present a distinct grouping organizing state approaches to professional Digital Examiner licensing. The authors conclude that states must differentiate between Private Investigator and Digital Examiner licensing requirements and oversight.

The Impact Of Hard Disk Firmware Steganography On Computer Forensics, Iain Sutherland, Gareth Davies, Nick Pringle, Andrew Blyth

Journal of Digital Forensics, Security and Law

The hard disk drive is probably the predominant form of storage media and is a primary data source in a forensic investigation. The majority of available software tools and literature relating to the investigation of the structure and content contained within a hard disk drive concerns the extraction and analysis of evidence from the various file systems which can reside in the user accessible area of the disk. It is known that there are other areas of the hard disk drive which could be used to conceal information, such as the Host Protected Area and the Device Configuration Overlay. There …

Electronic Forms-Based Computing For Evidentiary Analysis, Andy Luse, Brian Mennecke, Anthony M. Townsend

Journal of Digital Forensics, Security and Law

The paperwork associated with evidentiary collection and analysis is a highly repetitive and time-consuming process which often involves duplication of work and can frequently result in documentary errors. Electronic entry of evidencerelated information can facilitate greater accuracy and less time spent on data entry. This manuscript describes a general framework for the implementation of an electronic tablet-based system for evidentiary processing. This framework is then utilized in the design and implementation of an electronic tablet-based evidentiary input prototype system developed for use by forensic laboratories which serves as a verification of the proposed framework. The manuscript concludes with a discussion …

Graduate Accounting Students' Perception Of It Forensics: A Multi-Dimensional Analysis, Grover S. Kearns

Journal of Digital Forensics, Security and Law

Forensics and information technology (IT) have become increasingly important to accountants and auditors. Undergraduate accounting students are introduced to general IT topics but discussion of forensic knowledge is limited. A few schools have introduced an undergraduate major in forensic accounting. Some graduate schools offer accounting students an emphasis in forensic or fraud accounting that includes instruction in forensics and information technology. When students do not view the IT topics as being equally important to their careers as traditional accounting topics, these attitudes may reduce the quality of the course. In an effort to assess student attitudes, a survey of 46 …

Book Review: Cyber Security And Global Information Assurance: Threat Analysis And Response Solutions, Gary C. Kessler

Journal of Digital Forensics, Security and Law

I freely admit that this book was sent to me by the publisher for the expressed purpose of my writing a review and that I know several of the chapter authors. With that disclosure out of the way, let me say that the book is well worth the review (and I get to keep my review copy).
The preface to the book cites the 2003 publication of The National Strategy to Secure Cyberspace by the White House, and the acknowledgement by the U.S. government that our economy and national security were fully dependent upon computers, networks, and the telecommunications infrastructure. …

Experimental And Numerical Study Of A Proton Exchange Membrane Electrolyzer For Hydrogen Production, Sachin S. Deshmukh

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hydrogen as a fuel source has received attention from researchers globally due to its potential to replace fossil based fuels for energy production. Research is being performed on hydrogen production, storage and utilization methods to make its use economically feasible relative to current energy sources. The PEM electrolyzer is used to produce hydrogen and oxygen using water and electricity. Focus of our study is to provide a benchmark experiment and numerical model of a single cell electrolyzer that can assist in improving the current state of understanding of this system. Parametric analysis of an experimental cell was performed to understand …

Dc Electrokinetic Transport Of Cylindrical Cells In Straight Microchannels, Ye Ai, Ali Beskok, David T. Gauthier, Sang W. Joo, Shizhi Qian

Biological Sciences Faculty Publications

Electrokinetic transport of cylindrical cells under dc electric fields in a straight microfluidic channel is experimentally and numerically investigated with emphasis on the dielectrophoretic (DEP) effect on their orientation variations. A two-dimensional multiphysics model, composed of the Navier-Stokes equations for the fluid flow and the Laplace equation for the electric potential defined in an arbitrary Lagrangian-Eulerian framework, is employed to capture the transient electrokinetic motion of cylindrical cells. The numerical predictions of the particle transport are in quantitative agreement with the obtained experimental results, suggesting that the DEP effect should be taken into account to study the electrokinetic transport of …

Partial Program Admission, Michael Wilson, Ron Cytron, Jon Turner

All Computer Science and Engineering Research

Real-time systems on non-preemptive platforms require a means of bounding the execution time of programs for admission purposes. Worst-Case Execution Time (WCET) is most commonly used to bound program execution time. While bounding a program’s WCET statically is possible, computing its true WCET is difficult.We present a new technique we call partial program admission, a means of statically enforcing an otherwise untrusted assertion of WCET without adding runtime overhead, by means of code duplication. We apply this technique to real programs from the virtual networking arena and present the results.

Scheduling Design With Unknown Execution Time Distributions Or Modes, Robert Glaubius, Terry Tidwell, Christopher Gill, William D. Smart

All Computer Science and Engineering Research

Open soft real-time systems, such as mobile robots, experience unpredictable interactions with their environments and yet must respond both adaptively and with reasonable temporal predictability. Because of the uncertainty inherent in such interactions, many of the assumptions of the real-time scheduling techniques traditionally used to ensure predictable timing of system actions do not hold in those environments. In previous work we have developed novel techniques for scheduling policy design where up-front knowledge of execution time distributions can be used to produce both compact representations of resource utilization state spaces and efficient optimal scheduling policies over those state spaces. This paper …

Enabling A Low-Delay Internet Service Via Built-In Performance Incentives, Maxim Podlesny, Sergey Gorinsky

All Computer Science and Engineering Research

The single best-effort service of the Internet struggles to accommodate divergent needs of different distributed applications. Numerous alternative network architectures have been proposed to offer diversified network services. These innovative solutions failed to gain wide deployment primarily due to economic and legacy issues rather than technical shortcomings. Our paper presents a new simple paradigm for network service differentiation that accounts explicitly for the multiplicity of Internet service providers and users as well as their economic interests in environments with partly deployed new services. Our key idea is to base the service differentiation on performance itself, rather than price. We design …

Design Of An Extensible Network Testbed With Heterogeneous Components, Charlie Wisemen, Jyoti Parwatikar, Ken Wong, John Dehart, Jonathan Turner

All Computer Science and Engineering Research

Virtualized network infrastructures are currently deployed in both research and commercial contexts. The complexity of the virtualization layer varies greatly in different deployments, ranging from cloud computing environments, to carrier Ethernet applications using stacked VLANs, to networking testbeds. In all of these cases, there are many users sharing the resources of one provider, where each user expects their resources to be isolated from all other users. Our work in this area is focused on network testbeds. In particular, we present the design of the latest version of the Open Network Laboratory (ONL) testbed. This redesign generalizes the underlying infrastructure to …

Robust Sensor Networks In Homes Via Reactive Channel Hopping, Mo Sha, Greg Hackmann, Chenyang Lu

All Computer Science and Engineering Research

Home area networks (HANs) consisting of wireless sensors have emerged as the enabling technology for important applications such as smart energy and assisted living. A key challenge faced in deploying robust wireless sensor networks (WSNs) for home automation applications is the need to provide long-term, reliable operation in the face of the varied sources of interference found in typical residential settings. To better understand the channel dynamics in these environments, we performed an in-depth empirical study of the performance of HANs in ten real-life apartments. Our empirical study leads to several key insights into designing robust HANs for residential environments. …

Reliable Patient Monitoring: A Clinical Study In A Step-Down Hospital Unit, Octav Chipara, Chenyang Lu, Thomas C. Bailey, Gruia-Catalin Roman

All Computer Science and Engineering Research

This paper presents the design, deployment, and empirical study of a wireless clinical monitoring system that collects pulse and oxygen saturation readings from patients. The primary contribution of this paper is an in-depth clinical trial that assesses the feasibility of wireless sensor networks for patient monitoring in general (non-ICU) hospital units. The trial involved 32 patients monitored in a step-down cardiology unit at Barnes-Jewish Hospital, St. Louis. During a total of 31 days of monitoring, the network achieved high reliability (median 99.92%, range 95.21% - 100%). The overall reliability of the system was dominated by sensing reliability (median 80.55%, range …