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2007

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Articles 3421 - 3450 of 6758

Full-Text Articles in Physical Sciences and Mathematics

An Overview Of Adsl Homed Nepenthes Honeypots In Western Australia, Craig Valli, Aaron Wooten Mar 2007

An Overview Of Adsl Homed Nepenthes Honeypots In Western Australia, Craig Valli, Aaron Wooten

Australian Digital Forensics Conference

This paper outlines initial analysis from research in progress into ADSL homed Nepenthes honeypots. One of the Nepenthes honeypots prime objective in this research was the collection of malware for analysis and dissection. A further objective is the analysis of risks that are circulating within ISP networks in Western Australian. What differentiates Nepenthes from many traditional honeypot designs it that is has been engineered from a distributed network philosophy. The program allows distribution of results across a network of sensors and subsequent aggregation of malware statistics readily within a large network environment.

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An Overview And Examination Of Digital Pda Devices Under Forensics Toolkits, Krishnun Sansurooah Mar 2007

An Overview And Examination Of Digital Pda Devices Under Forensics Toolkits, Krishnun Sansurooah

Australian Digital Forensics Conference

Personal Digital Assistants most commonly known as PDAs are becoming more and more fashionable and affordable in the working environment. With the advent and rapidly increasing technology these handled devices are now targeted by a lot of person with criminal intentions. But unfortunately crime does not choose its technology and nowadays those ultra light handhelds are getting more and more involved in crimes. This therefore become an onerous task for the forensics examiners who needs the proper forensics tools to investigate the information held on these devices. The purpose of this report will browse the current forensics toolkits available and …

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Profiling Through A Digital Mobile Device, Lee Fueng Yap, Andy Jones Mar 2007

Profiling Through A Digital Mobile Device, Lee Fueng Yap, Andy Jones

Australian Digital Forensics Conference

Mobile digital devices have evolved from telecommunications device to a lifestyle product over the years. These devices are used in all aspects of our daily life. As a result, more information is stored within the devices. Unprotected mobile digital device is susceptible to privacy invasion attack when the device falls into the wrong hand of any unscrupulous third party. The main objective of this paper is to provide an implication analysis on the possible risks of information leakage through digital mobile devices, in the case when users forget to, or choose never to apply any security protection to their devices

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Forensic Analysis Avoidance Techniques Of Malware, Murray Brand Mar 2007

Forensic Analysis Avoidance Techniques Of Malware, Murray Brand

Australian Digital Forensics Conference

Anti-forensic techniques are increasingly being used by malware writers to avoid detection and analysis of their malicious code. Penalties for writing malware could include termination of employment, fines or even, imprisonment. Malware writers are motivated not to get caught and are actively using subversive techniques to avoid forensic analysis. Techniques employed include obfuscation, anti-disassembly, encrypted and compressed data, data destruction and anti-debugging. Automated detection and classification work is progressing in this field. This includes analysing statistical structures such as assembly instructions, system calls, system dependence graphs and classification through machine learning.

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A Proof-Of-Concept Project For Utilizing U3 Technology In Incident Response, Marwan Al-Zarouni, Haitham Al-Hajri Mar 2007

A Proof-Of-Concept Project For Utilizing U3 Technology In Incident Response, Marwan Al-Zarouni, Haitham Al-Hajri

Australian Digital Forensics Conference

This paper discusses the importance of live forensics and the use of an automated USB based smart data gathering technology to be used in incident response. The paper introduces the technology and its application in incidence response as well as highlight how it works. It also explains the tools that it uses to gather the live data from target systems. The paper also highlights some of the advantages and disadvantages of the technology as will as its limitations. The paper concludes with mentioning the importance of testing the tool and ways it can be developed and taken further.

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A Forensically Tested Tool For Identification Of Notebook Computers To Aid Recovery: Liars Phase I Proof Of Concept, Peter Hannay, Andrew Woodward, Nic Cope Mar 2007

A Forensically Tested Tool For Identification Of Notebook Computers To Aid Recovery: Liars Phase I Proof Of Concept, Peter Hannay, Andrew Woodward, Nic Cope

Australian Digital Forensics Conference

The LIARS tool was designed to enable identification, and potentially the return, to the rightful owner of stolen laptop or notebook computers. Many laptops are discovered by Police, but time constraints prevent recovered devices from being identified. This project has produced a proof of concept tool which can be used by virtually any police officer, or other investigator, which does not alter the hard drive in any fashion. The tool uses a modified version of the chntpw software, and is based on a forensically tested live Linux CD. The tool examines registry hives for known location of keys which may …

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Optical Tracking For Relative Positioning In Automated Aerial Refueling, James H. Spencer Mar 2007

Optical Tracking For Relative Positioning In Automated Aerial Refueling, James H. Spencer

Theses and Dissertations

An algorithm is designed to extract features from video of an air refueling tanker for use in determining the precise relative position of a receiver aircraft. The algorithm is based on receiving a known estimate of the tanker aircraft's position and attitude. The algorithm then uses a known feature model of the tanker to predict the location of those features on a video frame. A corner detector is used to extract features from the video. The measured corners are then associated with known features and tracked from frame to frame. For each frame, the associated features are used to calculate …

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A Study Of Bi-Directional Reflectance Distribution Functions And Their Effects On Infrared Signature Models, Samuel I. Harkiss Mar 2007

A Study Of Bi-Directional Reflectance Distribution Functions And Their Effects On Infrared Signature Models, Samuel I. Harkiss

Theses and Dissertations

Since 2004, AFIT has been developing a trend-analysis tool to assess large commercial aircraft infrared (LCAIR) signatures. In many cases, this code predicted signatures to within 10% of measured data. However, other results indicated that the single-bounce, specular-reflection algorithm being used failed to adequately simulate interactions between aircraft parts where either the specular component is dominated by diffuse reflection or part-to-part multiple-bounce reflections contribute significantly to the signature. This research incorporates Bi-Directional Reflectance Distribution Functions (BRDF's) and multiple-bounce calculations into the LCAIR model. A physical aircraft model was constructed from aluminum, and measurements were taken before and after a surface …

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Improving Machine Learning Through Oracle Learning, Joshua Ephraim Menke Mar 2007

Improving Machine Learning Through Oracle Learning, Joshua Ephraim Menke

Theses and Dissertations

The following dissertation presents a new paradigm for improving the training of machine learning algorithms, oracle learning. The main idea in oracle learning is that instead of training directly on a set of data, a learning model is trained to approximate a given oracle's behavior on a set of data. This can be beneficial in situations where it is easier to obtain an oracle than it is to use it at application time. It is shown that oracle learning can be applied to more effectively reduce the size of artificial neural networks, to more efficiently take advantage of domain experts …

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The Acs Survey Of Galactic Globular Clusters. I. Overview And Clusters Without Previoushubble Space Telescope Photometry, Ata Sarajedini, Luigi R. Bedin, Brian Chaboyer, Aaron Dotter, Michael H. Siegel, Jay Anderson, Antonio Aparicio, Ivan King, Steven R. Majewski, A. Marin-Franch, Giampolo Piotto, I. Neill Reid, Alfred Rosenberg Mar 2007

The Acs Survey Of Galactic Globular Clusters. I. Overview And Clusters Without Previoushubble Space Telescope Photometry, Ata Sarajedini, Luigi R. Bedin, Brian Chaboyer, Aaron Dotter, Michael H. Siegel, Jay Anderson, Antonio Aparicio, Ivan King, Steven R. Majewski, A. Marin-Franch, Giampolo Piotto, I. Neill Reid, Alfred Rosenberg

Dartmouth Scholarship

We present the first results of a large Advanced Camera for Surveys (ACS) survey of Galactic globular clusters. This Hubble Space Telescope (HST) Treasury project is designed to obtain photometry with S/N (signal-to-noise ratio) 10 for main-sequence stars with masses 0.2 M⊙ in a sample of globulars using the ACS Wide Field Channel. Here we focus on clusters without previous HST imaging data. These include NGC 5466, NGC 6779, NGC 5053, NGC 6144, Palomar 2, E3, Lyngå 7, Palomar 1, and NGC 6366. Our color-magnitude diagrams (CMDs) extend reliably from the horizontal branch to as much as …

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To Boldly Go: Current Work And Future Directions In Mathematics And Popular Culture, Christopher Goff, Sarah J. Greenwald Mar 2007

To Boldly Go: Current Work And Future Directions In Mathematics And Popular Culture, Christopher Goff, Sarah J. Greenwald

Christopher Goff

No abstract provided.

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Minimal Walking On The Lattice, Simon Catterall, Francesco Sannino Mar 2007

Minimal Walking On The Lattice, Simon Catterall, Francesco Sannino

Physics - All Scholarship

We provide the first evidence of a walking dynamics for two color lattice Yang-Mills theory with two Dirac flavors in the symmetric representation of the gauge group.

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Ria: An Rf Interference Avoidance Algorithm For Heterogeneous Wireless Networks, Daniel P. Delorey, Qiuyi Duan, Charles D. Knutson, Manoj Pandey, Lei Wang, Ryan W. Woodings, Daniel Zappala Mar 2007

Ria: An Rf Interference Avoidance Algorithm For Heterogeneous Wireless Networks, Daniel P. Delorey, Qiuyi Duan, Charles D. Knutson, Manoj Pandey, Lei Wang, Ryan W. Woodings, Daniel Zappala

Faculty Publications

Devices with multiple wireless interfaces are becoming increasingly popular. We envision that these devices will become the building block for future mesh networks, providing seamless connectivity across a range of heterogeneous devices. Although these devices typically implement frequency sharing, using either Direct Sequence Spread Spectrum (DSSS) or Frequency Hopping Spread Spectrum (FHSS), they may still interfere with one another. In this paper we provide a novel Radio Interference Avoidance (RIA) algorithm that solves the problem of interference between IEEE 802.11 and Bluetooth. We then extend this algorithm to other types of DSSS and FHSS combinations. Though the algorithm is limited …

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Modified Test Statistics By Inter-Voxel Variance Shrinkage With An Application To Fmri, Shu-Chih Su, Brian Caffo, Elizabeth Garrett-Mayer, Susan Bassett Mar 2007

Modified Test Statistics By Inter-Voxel Variance Shrinkage With An Application To Fmri, Shu-Chih Su, Brian Caffo, Elizabeth Garrett-Mayer, Susan Bassett

Johns Hopkins University, Dept. of Biostatistics Working Papers

Functional Magnetic Resonance Imaging (fMRI) is a non-invasive technique which is commonly used to quantify changes in blood oxygenation and flow coupled to neuronal activation. One of the primary goals of fMRI studies is to identify localized brain regions where neuronal activation levels vary between groups. Single voxel t-tests have been commonly used to determine whether activation related to the protocol differs across groups. Due to the generally limited number of subjects within each study, accurate estimation of variance at each voxel is difficult. Thus, combining information across voxels in the statistical analysis of fMRI data is desirable in order …

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Does Spelling Count? Reflections On Writing In The Mathematics Classroom, Christopher D. Goff Mar 2007

Does Spelling Count? Reflections On Writing In The Mathematics Classroom, Christopher D. Goff

College of the Pacific Faculty Presentations

The written word is scarce in the stereotypical mathematics course, which instead emphasizes the routine solving of problems. But having students explain their solutions in writing can pave the way to more critical mathematical thinking. This talk will examine the use of writing as a tool to learn mathematics. We will reflect on: reasons to incorporate writing in a mathematics class; which courses lend themselves to writing assignments; what types of assignments to use; samples of student work; and whether using writing can actually improve student learning. Depending on the assignments, writing can also incorporate several “Basic Principles” of AMATYC’s …

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Refinement Of An Instrument To Assess Readiness For Knowledge Management, Landon C. Bailey Mar 2007

Refinement Of An Instrument To Assess Readiness For Knowledge Management, Landon C. Bailey

Theses and Dissertations

Academics and practitioners have described knowledge as a primary source for competitive advantage for organizations; however, many attempts at instituting knowledge management programs to increase organizational competitiveness do not succeed. Instituting knowledge management programs generally requires organizations to make significant changes and the concept of readiness has long been believed to be an important precondition for successful organizational change. By linking previous research in enablers for knowledge management and organizational change, it is possible to adapt an established organizational change readiness instrument to measure readiness for knowledge management. This study culminates in the development and field-testing of the resultant knowledge …

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The Effects Of Orthophosphate As A Copper Corrosion Control Inhibitor In High Alkalinity Drinking Water Systems, Stephen Grace Mar 2007

The Effects Of Orthophosphate As A Copper Corrosion Control Inhibitor In High Alkalinity Drinking Water Systems, Stephen Grace

Theses and Dissertations

The purpose of this research was to investigate orthophosphate as a corrosion inhibitor for copper pipe in a high-alkalinity drinking water system. Specifically, this thesis sought to answer three research questions regarding the impact of orthophosphate treatment, the nature of the mechanism by which orthophosphate controls copper corrosion, and the value of equilibrium modeling in predicting orthophosphate’s effects. The research questions were answered through a comprehensive literature review and experimental methodology integrating laboratory jar tests, water sampling and analysis from a field investigation, qualitative solids analysis, and equilibrium model application. This study analyzed field data obtained over the course of …

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Unraveling The Catalytic Mechanism Of Nitrile Hydratases, Sanghamitra Mitra, Richard C. Holz Mar 2007

Unraveling The Catalytic Mechanism Of Nitrile Hydratases, Sanghamitra Mitra, Richard C. Holz

Chemistry Faculty Research and Publications

To elucidate a detailed catalytic mechanism for nitrile hydratases (NHases), the pH and temperature dependence of the kinetic constants kcat and Km for the cobalt-type NHase from Pseudonocardia thermophila JCM 3095 (PtNHase) were examined. PtNHase was found to exhibit a bell-shaped curve for plots of relative activity versus pH at pH 3.2–11 and was found to display maximal activity between pH 7.2 and 7.8. Fits of these data provided pKES1 and pKES2 values of 5.9 ± 0.1 and 9.2 ± 0.1 (kcat′ = 130 ± 1 …

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Polar Research: School Of Rock, Alexandra Witze Mar 2007

Polar Research: School Of Rock, Alexandra Witze

ANDRILL Research and Publications

As Antarctica’s ice teams continue to hunt for the oldest ice their drills will reach, a smaller band of rockhounds is on a similar quest to plug the gaps in the geological record. The team now has a core that promises fresh insight into how Antarctica’s ice waxed and waned over the past few million years. On December 26, 2006, a US$30-million international project called ANDRILL pulled up the final piece of a core from beneath the Ross ice shelf. Previous coring efforts have offered peeks into Antarctica’s deep history — back as far as 34 million years when the …

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Obstacle Annotation By Demonstration, Michael David Clement Mar 2007

Obstacle Annotation By Demonstration, Michael David Clement

Theses and Dissertations

By observing human driving with a “digital head" (combined video camera and accelerometers) and taking a few hand annotations, we can automatically annotate regions in a robot's field of view that should be interpreted as obstacles to be avoided. This is accomplished by detecting the movement for a given frame in a video. Some hand annotations of video frames are necessary and they are used to create Probability Grids. Using the movement data and the Probability Grids, it is possible to annotate large amounts of video data quickly in an automated system.

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Pyridinium Bis-Retinoids: Extraction, Synthesis, And Folate Coupling, Mary Allison Alvarez Mar 2007

Pyridinium Bis-Retinoids: Extraction, Synthesis, And Folate Coupling, Mary Allison Alvarez

Theses and Dissertations

This thesis is divided into two parts.Part I describes the organic extraction, separation, and liquid chromatographic-mass spectrometric analysis of chromophores from human and bovine retinal pigment epithelium. Flurorophores in the retinal pigment epithelium have been implicated in age related macular degeneration. In addition, the synthesis and characterization of a number of bis-retinoid type compounds that may potentially be found in such extracts, or that may be used for insight into pyridinium bis-retinoid reactivity, was accomplished.Part II describes a study of pyridinium bis-retinoid-folic acid coupling with respect to linker type, linker length, and nature of the linkage. Folic acid has been …

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The Lability Of Riverine Particulate Organic Carbon Delivered To The Ocean, Lawrence Mayer Mar 2007

The Lability Of Riverine Particulate Organic Carbon Delivered To The Ocean, Lawrence Mayer

University of Maine Office of Research Administration: Grant Reports

The large annual flux of organic carbon from land to the ocean largely disappears in the sea. Reasons for this loss are not clear. Under this award, the PI will examine abiotic and biotic aspects of the lability to loss of riverine particulate organic matter. Work will focus on the Mississippi, as it demonstrates the clearest loss of particulate organic material of any North American river upon deposition in the ocean. Photochemical experiments will follow up on initial work showing significant dissolution of particulate organic matter subjected to solar levels of radiation. Interactions with metal cycling will be studied, as …

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Bayesian Meta-Analysis Models For Microarray Data: A Comparative Study, Erin M. Conlon, Joon J. Song, Anna Liu Mar 2007

Bayesian Meta-Analysis Models For Microarray Data: A Comparative Study, Erin M. Conlon, Joon J. Song, Anna Liu

Erin M. Conlon

Background With the growing abundance of microarray data, statistical methods are increasingly needed to integrate results across studies. Two common approaches for meta-analysis of microarrays include either combining gene expression measures across studies or combining summaries such as p-values, probabilities or ranks. Here, we compare two Bayesian meta-analysis models that are analogous to these methods. Results Two Bayesian meta-analysis models for microarray data have recently been introduced. The first model combines standardized gene expression measures across studies into an overall mean, accounting for inter-study variability, while the second combines probabilities of differential expression without combining expression values. Both models produce …

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The Effect Of Birth Order On Infant Injury, Heather L. Van Duker Mar 2007

The Effect Of Birth Order On Infant Injury, Heather L. Van Duker

Theses and Dissertations

Pediatric injury is both common and expensive. Finding ways to prevent pediatric injury is a major public health concern. Many studies have investigated various aspects of pediatric injury, and some suggest that birth order may be an important risk factor for pediatric injury. This study further examined the relationship of birth order with pediatric injury, specifically studying the association of birth order with emergency department-attended infant injury while adjusting for other important family and individual covariates. Data for analysis included Utah birth certificate, death certificate, and hospital emergency department datasets, which were probabilistically linked to obtain complete demographic and injury …

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Grating Lobe Reduction In Transducer Arrays Through Structural Filtering Of Supercritical Plates, Brian E. Anderson, Stephen A. Hambric, Jack W. Hughes Mar 2007

Grating Lobe Reduction In Transducer Arrays Through Structural Filtering Of Supercritical Plates, Brian E. Anderson, Stephen A. Hambric, Jack W. Hughes

Faculty Publications

The effect of placing a structural acoustic filter between water and the transducer elements of an array to help reduce undesirable grating lobes is investigated. A supercritical plate is mounted to transducer elements with a thin decoupling polyurethane layer between the transducers and the plate. The plate acts as a radiation/incidence angle filter to pass energy at angles near normal incidence, but suppress energy at large incidence angles. Grating lobe reduction is achieved at the expense of limiting the available steering of the main lobe. Within this steer angle limitation, the main lobe can be steered as normal while the …

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Short Note On Polyphases Pd-Pt-Te Mineralisations Which Is Determined In Rutile Bearing Berit Metaophiolite Chromitites In Kahramanmaraş, Hatice Kozlu Erdal Mar 2007

Short Note On Polyphases Pd-Pt-Te Mineralisations Which Is Determined In Rutile Bearing Berit Metaophiolite Chromitites In Kahramanmaraş, Hatice Kozlu Erdal

Bulletin of the Mineral Research and Exploration

No abstract provided.

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Bayesian Meta-Analysis Models For Microarray Data: A Comparative Study, Erin M. Conlon, Joon J. Song, Anna Liu Mar 2007

Bayesian Meta-Analysis Models For Microarray Data: A Comparative Study, Erin M. Conlon, Joon J. Song, Anna Liu

Anna Liu

Background With the growing abundance of microarray data, statistical methods are increasingly needed to integrate results across studies. Two common approaches for meta-analysis of microarrays include either combining gene expression measures across studies or combining summaries such as p-values, probabilities or ranks. Here, we compare two Bayesian meta-analysis models that are analogous to these methods. Results Two Bayesian meta-analysis models for microarray data have recently been introduced. The first model combines standardized gene expression measures across studies into an overall mean, accounting for inter-study variability, while the second combines probabilities of differential expression without combining expression values. Both models produce …

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Using Concept Maps To More Efficiently Create Intelligence Information Models, Christopher E. Coryell Mar 2007

Using Concept Maps To More Efficiently Create Intelligence Information Models, Christopher E. Coryell

Theses and Dissertations

Information models are a critical tool that enables intelligence customers to quickly and accurately comprehend U.S. intelligence agency products. The Knowledge Pre-positioning System (KPS) is the standard repository for information models at the National Air and Space Intelligence Center (NASIC). The current approach used by NASIC to build a KPS information model is laborious and costly. Intelligence analysts design an information model using a manual, butcher-paper-based process. The output of their work is then entered into KPS by either a single NASIC KPS "database modeler" or a contractor (at a cost of roughly $100K to the organization). This thesis proposes …

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Use Of Thrust Vectors In Support Of The Cybercraft Initiative, Michael Stevens Mar 2007

Use Of Thrust Vectors In Support Of The Cybercraft Initiative, Michael Stevens

Theses and Dissertations

The CyberCraft Initiative is designing a framework for command and control of future Air Force Cyber-weapon systems, that autonomously operate and defend the Air Force networks and information systems to provide Cyberspace Superiority in support of the defense of the United States. The fundamental research question of the CyberCraft Initiative is "What is required for a commander to trust a CyberCraft to autonomously defend military information systems?" The Trust Vector model is one method of integrating trust into the CyberCraft fleet. Trust Vectors define trust and distrust between agents based on three components; current and historical data, intrinsic knowledge of …

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Implementation And Optimization Of The Advanced Encryption Standard Algorithm On An 8-Bit Field Programmable Gate Array Hardware Platform, Ryan J. Silva Mar 2007

Implementation And Optimization Of The Advanced Encryption Standard Algorithm On An 8-Bit Field Programmable Gate Array Hardware Platform, Ryan J. Silva

Theses and Dissertations

The contribution of this research is three-fold. The first is a method of converting the area occupied by a circuit implemented on a Field Programmable Gate Array (FPGA) to an equivalent as a measure of total gate count. This allows direct comparison between two FPGA implementations independent of the manufacturer or chip family. The second contribution improves the performance of the Advanced Encryption Standard (AES) on an 8-bit computing platform. This research develops an AES design that occupies less than three quarters of the area reported by the smallest design in current literature as well as significantly increases area efficiency. …

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