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2009

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An Enhanced Data Mining Life Cycle, Markus Hofmann, Brendan Tierney Jan 2009

An Enhanced Data Mining Life Cycle, Markus Hofmann, Brendan Tierney

Conference papers

Data mining projects are complex and can have a high failure rate. In order to improve project management and success rates of such projects a life cycle is vital to the overall success of the project. This paper reports on a research project that was concerned with the life cycle development for data mining projects, its team members and their role. The paper provides a detailed view of the design and development of the data mining life cycle called DMLC. The life cycle aims to support all members of data mining project teams as well as IT managers and academic …

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Evaluation Of Mixed-Effects Modeling Techniques For The Analysis Of Longitudinal Data Collected From Pk-Pd And Efficacy Clinical Trials, Rajesh Narwal Jan 2009

Evaluation Of Mixed-Effects Modeling Techniques For The Analysis Of Longitudinal Data Collected From Pk-Pd And Efficacy Clinical Trials, Rajesh Narwal

Open Access Dissertations

Linear and non-linear mixed effects modeling techniques are of great importance for the analysis of repeated measure data collected from various pharmacokinetic (PK)-pharmacodynamic (PD) and efficacy clinical trial during drug development. Monte-Carlo simulations were used to evaluate and compare the properties of mixed-model for repeated measure (MMRM) to fixed-effects ANOVA. The methods were compared using three different response profiles, four types of correlation structures (unstructured, compound symmetry, autoregressive and Toeplitz) and three types of missing mechanisms (MCAR (missing completely at random), MAR (missing at random) and MNAR (missing not at random). The MMRM methods adequately controlled type-I error and provided …

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Three Essays On Corporate Pension Underfunding, Securities Valuation And Market Efficiency, Ting Zhang Jan 2009

Three Essays On Corporate Pension Underfunding, Securities Valuation And Market Efficiency, Ting Zhang

Open Access Dissertations

This dissertation consists of three essays on corporate pension plan underfunding and securities valuation. The first essay presents evidence that sell-side stock analysts systematically underreact to pension underfunding information when they forecast firm earnings and such underreaction is associated with future stock returns. The second essay examines the effect of pension obligation overhang on ratings of a firm's bond issues with different seniority. It shows that both the level and changes of pension obligations have significant effects on bond ratings and bond liquidity of non-senior secured issues (including senior unsecured, senior subordinate, subordinate, and junior subordinate bonds), but have no …

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Making Room For One Another: Practicing Dynamic And Designed Dialogicality In A Kindergarten Classroom, Gerri August Jan 2009

Making Room For One Another: Practicing Dynamic And Designed Dialogicality In A Kindergarten Classroom, Gerri August

Open Access Dissertations

The territory of this critical ethnography lies at the intersection of democratic, transformative pedagogy and differences that made a difference in an urban kindergarten. It is an interpretation of a democratic, transformative educator responding to sociocultural differences that emerged in the classroom discourse. Often, such differences lead to otherization. This study interprets the constraints and possibilities that encouraged students to recognize and respect difference. The kindergarten classroom is interpreted in the framework of activity theory. Drawing largely on discourse analysis, this interpretation turns on the interplay between two primary elements in the activity system. The first is Zeke, the kindergarten …

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On The Dynamics Of Oceanic Gap-Traversing Boundary Currents, Joseph J. Kuehl Jan 2009

On The Dynamics Of Oceanic Gap-Traversing Boundary Currents, Joseph J. Kuehl

Open Access Dissertations

Rotating-table laboratory experiments of oceanic gap-traversing boundary currents are considered. The experimental setup is designed to mimic a predominantly inertial boundary current, which impinges on a quasigeostrophic interior when encountering a gap in its supporting boundary. The current separates from the boundary, negotiates the gap and reattaches to the boundary. This is the case in oceanic situations such as the Kuroshio encountering the Luzon Strait and the Gulf Stream in the mouth of the Gulf of Mexico. Observation of such regions have shown the current to either leap directly across the gap or penetrate into the gap, forming a loop …

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Subseafloor Sulfate Reduction: Investigation Of An Unrecognized Pathway And Quantification Of Low Rates, Heather Nicole Schrum Jan 2009

Subseafloor Sulfate Reduction: Investigation Of An Unrecognized Pathway And Quantification Of Low Rates, Heather Nicole Schrum

Open Access Dissertations

Bacterially-catalyzed sulfate reduction is the dominant respiratory pathway in much of the deep subseafloor sediment, where it yields energy for a significant fraction of the Earth's total biomass. Sulfate reduction impacts the ecology of the deep biosphere, the biogeochemistry of sediment pore water and the global marine sulfur and carbon cycles. Chemical concentration profiles, thermodynamics, and sulfate isotopic compositions are a few of the methods used to determine the presence of sulfate reduction, its biochemical mechanisms, and the rates at which it occurs. By employing these methods we show that a previously unrecognized sulfate reduction pathway is likely to occur …

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A Quantitative Study Of The Summer Slide In Science Of Elementary School Students, Giovanna Guadagno Donoyan Jan 2009

A Quantitative Study Of The Summer Slide In Science Of Elementary School Students, Giovanna Guadagno Donoyan

Open Access Dissertations

Concerned parents and educators agree children learn best when the rhythm of instruction is continuous with practice and application of skills. Long summer breaks may interrupt the flow of formal school learning leading some students to forget previous instruction. A review of the previous school work is generally required in the fall upon return from the summer vacation. Investigating summer vacation and equity issues, Jamar (1994) noted that more affluent students may "return to school in the fall with a considerable educational advantage over their less advantaged peers as a result of either additional school-related learning, or lower levels of …

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Exploring Some Inattended Affective Factors In Performing Nonroutine Mathematical Tasks, John D. Butler Jan 2009

Exploring Some Inattended Affective Factors In Performing Nonroutine Mathematical Tasks, John D. Butler

Open Access Dissertations

The purpose of this study was to describe students' attempts to solve nonroutine math problems and to explore possible correlates of their performance. The focus of this study was on inattended (i.e., intentionally avoided) dimensions that have been underrepresented in the literature, including attitudes, interests, values, aesthetics, metacognition, and representation. Both objective and subjective data--drawn from 13 separate sources--using quantitative and qualitative procedures, were analyzed. Fine-grained rubrics were developed and used to score student work on six nonroutine math problems. These objective data were complemented with students' written "logs" of their work in real time, followed by semi-structured debriefing interviews …

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Children Of Possibility: Children's Musicking In Communities Of Practice, Kimberly Cotter-Lemus Jan 2009

Children Of Possibility: Children's Musicking In Communities Of Practice, Kimberly Cotter-Lemus

Open Access Dissertations

Inner-city youth are often labeled in social science research with the "at risk" construct, signifying the risk of anticipated failure based on children's (or families') deficiencies. In the context of an arts project, the inner-city students in this study demonstrated ability to overcome the deficient "at risk" label imposed by society. The year-long, teacher-practitioner research took place in an underprivileged K-5 elementary school in the Northeast. Using a sociocultural framework, I examined what happens when children in this school setting are given an arts project in which they are allowed to be self-directive. The arts project consisted of weekly participation …

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Nonpoint Source Pollutant Monitering On The Ponaganset River Watershed, John C. Arruda Jr. Jan 2009

Nonpoint Source Pollutant Monitering On The Ponaganset River Watershed, John C. Arruda Jr.

Open Access Master's Theses

The Ponaganset River Basin consists of an area of 14.4 mi2 located in the town of Foster, Rhode Island. This area is located within the northwest region of the Scituate Watershed. The source of this river comes from the Ponaganset Reservoir with an area of 2.1 mi2 and a storage capacity of 742 MG. Water quality samples were collected at United States Geological Survey (USGS) site (01115187) which is approximately 5 miles down stream from the reservoir and 0.4 miles upstream from Barden Reservoir. The Ponaganset River has the largest mean daily discharge of all the sampling locations in the …

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Partial Order Reduction For Planning, You Xu Jan 2009

Partial Order Reduction For Planning, You Xu

All Theses and Dissertations (ETDs)

Partial Order Reduction: POR) is a technique that reduces the search space by recognizing interchangeable orders between actions and expanding only a subset of all possible orders during the search. It has been extensively studied in model checking and has proven to be an enabling technique for reducing the search space and costs. Several POR algorithms have been proposed in planning, including the Expansion Core: EC) and Stratified Planning: SP) algorithms. Being orthogonal to the development of accurate heuristic functions, these reduction methods show great potential to improve the planning efficiency from a new perspective. However, it is unclear how …

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Development And Implementation Of Fully 3d Statistical Image Reconstruction Algorithms For Helical Ct And Half-Ring Pet Insert System, Daniel Keesing Jan 2009

Development And Implementation Of Fully 3d Statistical Image Reconstruction Algorithms For Helical Ct And Half-Ring Pet Insert System, Daniel Keesing

All Theses and Dissertations (ETDs)

X-ray computed tomography: CT) and positron emission tomography: PET) have become widely used imaging modalities for screening, diagnosis, and image-guided treatment planning. Along with the increased clinical use are increased demands for high image quality with reduced ionizing radiation dose to the patient. Despite their significantly high computational cost, statistical iterative reconstruction algorithms are known to reconstruct high-quality images from noisy tomographic datasets. The overall goal of this work is to design statistical reconstruction software for clinical x-ray CT scanners, and for a novel PET system that utilizes high-resolution detectors within the field of view of a whole-body PET scanner. …

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Numerical Drag Reduction Studies On Generic Truck, Miles Bellman Jan 2009

Numerical Drag Reduction Studies On Generic Truck, Miles Bellman

All Theses and Dissertations (ETDs)

Drag reduction studies on generic truck models using passive shape optimization and active flow control are studied using numerical methods. A genetic algorithm is used to find optimal truck front shapes for reduced drag. The best shape found gives a 3.4% drag reduction. Active flow control is used to reduce drag by using oscillatory synthetic jet actuators on a generic truck body, a D-shaped bluff body, and the Ahmed body. Experimental data is available for these three configurations without and with active flow control. Actuators at the back of the trucks energize separating boundary layers and delay the shedding of …

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Discounting Of Delayed And Probabilistic Rewards By Women With And Without Binge Eating Disorder, Jamie Manwaring Jan 2009

Discounting Of Delayed And Probabilistic Rewards By Women With And Without Binge Eating Disorder, Jamie Manwaring

All Theses and Dissertations (ETDs)

Obese individuals with binge eating disorder: BED) exhibit more general and eating-disordered psychopathology than obese individuals without BED. Binge eating also impedes weight-loss efforts, already difficult in an obese population. A better basic understanding of binge eating and obesity is needed to refine treatments for both conditions. Discounting, an experimental paradigm that examines changes in the value of delayed or uncertain outcomes, may provide an objective assessment of impulsive behavior. Impulsivity may perpetuate binge eating, but discounting tasks have never been evaluated with eating disordered individuals. A discounting procedure could help differentiate individuals with eating/weight problems from controls in terms …

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Structural Rna Homology Search And Alignment Using Covariance Models, Eric Nawrocki Jan 2009

Structural Rna Homology Search And Alignment Using Covariance Models, Eric Nawrocki

All Theses and Dissertations (ETDs)

Functional RNA elements do not encode proteins, but rather function directly as RNAs. Many different types of RNAs play important roles in a wide range of cellular processes, including protein synthesis, gene regulation, protein transport, splicing, and more. Because important sequence and structural features tend to be evolutionarily conserved, one way to learn about functional RNAs is through comparative sequence analysis - by collecting and aligning examples of homologous RNAs and comparing them. Covariance models: CMs) are powerful computational tools for homology search and alignment that score both the conserved sequence and secondary structure of an RNA family. However, due …

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The Mechanisms And Roles Of Feedback Loops For Visual Processing, Jing Shao Jan 2009

The Mechanisms And Roles Of Feedback Loops For Visual Processing, Jing Shao

All Theses and Dissertations (ETDs)

Signal flow in the brain is not unidirectional; feedback represents a key element in neural signal processing. To address the question on how do neural feedback loops work in terms of synapses, microcircuitry, and systems dynamics, we developed a chick midbrain slice preparation to study and characterize one important feedback loop within the avian visual system: isthmotectal feedbackloop. The isthmotectal feedback loop consists of the optic tectum: OT) and three nucleus isthmi: Imc, Ipc and SLu. The tectal layer 10 neurons project to ipsilateral Imc, Ipc and SLu in a topographic way. In turn Ipc and SLu send back topographical: …

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Electrocardiographic Consequences Of Electrical And Anatomical Remodeling In Diabetic And Obese Humans, Shuli Wang Jan 2009

Electrocardiographic Consequences Of Electrical And Anatomical Remodeling In Diabetic And Obese Humans, Shuli Wang

All Theses and Dissertations (ETDs)

Background. Diabetes and obesity are two major risk factors for cardiovascular disease. Both can cause changes due to cardiac sources in body-surface potentials: BSPs), that is, in electrocardiograms: ECGs). By identifying the major effects of diabetes and obesity on BSPs, we hope to reveal the electrical phenotype of diabetes in body-surface ECGs in the presence of obesity. Methods. A Bidomain Platform was constructed to link heart-surface transmembrane potentials: TMPs) and BSPs. The Forward-Problem Module of the platform calculates BSPs from a bidomain-model of myocyte TMPs and torso anatomy. The platform also contains a Cardio-myocyte TMP Estimation Module in which an …

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Properties Of Neutron Star Critical Collapses, Mew-Bing Wan Jan 2009

Properties Of Neutron Star Critical Collapses, Mew-Bing Wan

All Theses and Dissertations (ETDs)

Critical phenomena in gravitational collapse opened a new mathematical vista into the theory of general relativity and may ultimately entail fundamental physical implication in the astrophysical realm, especially in gravitational collapse scenarios. However, at present, the dynamics of critical phenomena in realistic astrophysical gravitational collapse scenarios are still largely unknown. My thesis seeks to understand the properties of the neutron star critical solution, understand the properties of the threshold in the solution space of the Einstein field equations between the black hole and a neutron star phases, and clarify the implication these results on realistic astrophysical scenarios. We develop a …

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Contributions To The Methodology Of Electrocardiographic Imaging (Ecgi) And Application Of Ecgi To Study Mechanisms Of Atrial Arrhythmia, Post Myocardial Infarction Electrophysiological Substrate, And Ventricular Tachycardia In Patients, Yong Wang Jan 2009

Contributions To The Methodology Of Electrocardiographic Imaging (Ecgi) And Application Of Ecgi To Study Mechanisms Of Atrial Arrhythmia, Post Myocardial Infarction Electrophysiological Substrate, And Ventricular Tachycardia In Patients, Yong Wang

All Theses and Dissertations (ETDs)

ABSTRACT OF THE DISSERTATION Contributions to the Methodology of Electrocardiographic Imaging: ECGI) and Application of ECGI to Study Mechanisms of Atrial Arrhythmia, Post Myocardial Infarction Electrophysiological Substrate, and Ventricular Tachycardia in Patients by Yong Wang Doctor of Philosophy in Biomedical Engineering Washington University in St. Louis, 2009 Professor Yoram Rudy, Chair Electrocardiographic Imaging: ECGI) is a noninvasive imaging modality for cardiac electrophysiology and arrhythmia. ECGI reconstructs epicardial potentials, electrograms and isochrones from body-surface electrocardiograms combined with heart-torso geometry from computed tomography: CT). The application of a new meshless method, the Method of Fundamental Solutions: MFS) is introduced to ECGI with …

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Graduate Accounting Students' Perception Of It Forensics: A Multi-Dimensional Analysis, Grover S. Kearns Jan 2009

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 …

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Continuous Fraud Detection In Enterprise Systems Through Audit Trail Analysis, Peter J. Best, Pall Rikhardsson, Mark Toleman Jan 2009

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 …

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Table Of Contents Jan 2009

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

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Detection Of Steganography-Producing Software Artifacts On Crime-Related Seized Computers, Asawaree Kulkarni, James Goldman, Brad Nabholz, William Eyre Jan 2009

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 …

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Correlating Orphaned Windows Registry Data Structures, Damir Kahvedžić, Tahar Kechadi Jan 2009

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 …

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Insecurity By Obscurity: A Review Of Soho Router Literature From A Network Security Perspective, Patryk Szewczyk, Craig Valli Jan 2009

Insecurity By Obscurity: A Review Of Soho Router Literature From A Network Security Perspective, Patryk Szewczyk, Craig Valli

Journal of Digital Forensics, Security and Law

Because of prevalent threats to SoHo based ADSL Routers, many more devices are compromised. Whilst an end-user may be at fault for not applying the appropriate security mechanisms to counter these threats, vendors should equally share the blame. This paper reveals that the lack of security related content and poor overall design could impact on end-users’ interpretation and willingness to implement security controls on their ADSL router. It argues that whilst the number of threats circulating the Internet is increasing, vendors are not improving their product literature.

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Electronic Forms-Based Computing For Evidentiary Analysis, Andy Luse, Brian Mennecke, Anthony M. Townsend Jan 2009

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 …

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Book Review: Cyber Security And Global Information Assurance: Threat Analysis And Response Solutions, Gary C. Kessler Jan 2009

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. …

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Table Of Contents Jan 2009

Table Of Contents

Journal of Digital Forensics, Security and Law

No abstract provided.

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A Synopsis Of Proposed Data Protection Legislation In Sa, Francis S. Cronjé Jan 2009

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 …

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Prevention Is Better Than Prosecution: Deepening The Defence Against Cyber Crime, Jacqueline Fick Jan 2009

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 …

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