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2012

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Full-Text Articles in Physical Sciences and Mathematics

Optimal Error Of Query Sets Under The Differentially-Private Matrix Mechanism, Chao Li, Gerome Miklau Dec 2012

Optimal Error Of Query Sets Under The Differentially-Private Matrix Mechanism, Chao Li, Gerome Miklau

Gerome Miklau

A common goal of privacy research is to release synthetic data that satisfies a formal privacy guarantee and can be used by an analyst in place of the original data. To achieve reasonable accuracy, a synthetic data set must be tuned to support a specified set of queries accurately, sacrificing fidelity for other queries.

This work considers methods for producing synthetic data under differential privacy and investigates what makes a set of queries "easy" or "hard" to answer. We consider answering sets of linear counting queries using the matrix mechanism, a recent differentially-private mechanism that can reduce error by adding …


Simulations In 3d Tactics, Interdiction And Multi-Agent Modelling, A. R. Green, I. C. Piper, Daniel Keep, C. J. Flaherty Dec 2012

Simulations In 3d Tactics, Interdiction And Multi-Agent Modelling, A. R. Green, I. C. Piper, Daniel Keep, C. J. Flaherty

Dr Ian Piper

The analysis of vulnerabilities in large complex spaces is fundamentally problematic. The lack of capacity to generate a threat assessment merely exacerbates this problem. Lacking as well, in current literature is a developed methodology. To overcome this problem, we propose an approach using multi-agent modelling, which is also melded with three dimensional (3D) tactical understandings. Our approach builds on a microsimulation decision support tool, which was developed for a behavioural simulation of CBRN events. Microsimulation is based on the individual; who as an individual has a number of attributes, and which are stochastic (when repeated within an attribute). This approach …


Simple, Robust And Accurate Head-Pose Tracking Using A Single Camera, S. Meers, Koren Ward, I. Piper Dec 2012

Simple, Robust And Accurate Head-Pose Tracking Using A Single Camera, S. Meers, Koren Ward, I. Piper

Dr Ian Piper

This paper describes an inexpensive, robust method for tracking the head position and orientation of the user by using a single low-cost USB camera and infrared light emitting diodes concealed within spectacle frames worn by the user. Unlike gaze and head-pose tracking systems which rely on high-resolution stereo cameras and complex image processing hardware and software to find and track facial features on the user, the proposed system is able to efficiently locate and track the head's orientation and distance relative to the camera with little processing. Due to the infrared light emitting diodes having fixed geometry, the system does …


Application Of Web Mashup Technology To Oyster Information Services, Christian Chuindja Ngniah Dec 2012

Application Of Web Mashup Technology To Oyster Information Services, Christian Chuindja Ngniah

University of New Orleans Theses and Dissertations

Web mashup is a lightweight technology used to integrate data from remote sources without direct access to their databases. As a data consumer, a Web mashup application creates new contents by retrieving data through the Web application programming interface (API) provided by the external sources. As a data provider, the service program publishes its Web API and implements the specified functions.

In the project reported by this thesis, we have implemented two Web mashup applications to enhance the Web site oystersentinel.org: the Perkinsus marinus model and the Oil Spill model. Each model overlay geospatial data from a local database …


Application Of Digital Forensic Science To Electronic Discovery In Civil Litigation, Brian Roux Dec 2012

Application Of Digital Forensic Science To Electronic Discovery In Civil Litigation, Brian Roux

University of New Orleans Theses and Dissertations

Following changes to the Federal Rules of Civil Procedure in 2006 dealing with the role of Electronically Stored Information, digital forensics is becoming necessary to the discovery process in civil litigation. The development of case law interpreting the rule changes since their enactment defines how digital forensics can be applied to the discovery process, the scope of discovery, and the duties imposed on parties. Herein, pertinent cases are examined to determine what trends exist and how they effect the field. These observations buttress case studies involving discovery failures in large corporate contexts along with insights on the technical reasons those …


Methodology And Automated Metadata Extraction From Multiple Volume Shadow Copies, Henri Michael Van Goethem Dec 2012

Methodology And Automated Metadata Extraction From Multiple Volume Shadow Copies, Henri Michael Van Goethem

Masters Theses, 2010-2019

Modern day digital forensics investigations rely on timelines as a principal method for normalizing and chronologically categorizing artifacts recovered from computer systems. Timelines provide investigators with a chronological representation of digital evidence so they can depict altered and unaltered digital forensics data in-context to drive conclusions about system events and/or user activities. While investigators rely on many system artifacts such as file system time/date stamps, operating system artifacts, program artifacts, logs, and/or registry artifacts as input for deriving chronological representations, using only the available or most recent version of the artifacts may provide a limited picture of historical changes on …


Investigating Volatility Trends Of Silver Through An Analysis Of Stock Options Prices, Dylan Houston Dec 2012

Investigating Volatility Trends Of Silver Through An Analysis Of Stock Options Prices, Dylan Houston

Honors Theses

Volatility is a statistical measure that describes the amount of fluctuation in prices for a given investment; generally, the higher the volatility for an investment, the riskier it is perceived to be. Traders study volatility history so that they can make informed decisions on how to invest capital. The purpose of this article is to analyze implied volatility values, which are derived from the investment's price and are considered the market's estimate of the investment's actual volatility, for silver electronically traded fund (ETF) options in periods of both high and low price movement. In doing so, we desired to see …


Connotational Subtyping And Runtime Class Mutability In Ruby, Ian S. Dillon Dec 2012

Connotational Subtyping And Runtime Class Mutability In Ruby, Ian S. Dillon

Electronic Theses and Dissertations

Connotational subtyping is an approach to typing that allows an object's type to change dynamically, following changes to the object's internal state. This allows for a more precise representation of a problem domain with logical objects that have variable behavior. Two approaches to supporting connotational subtyping in the Ruby programming language were implemented: a language-level implementation using pure Ruby and a modification to the Ruby 1.8.7 interpreter. While neither implementation was wholly successful the language level implementation created complications with reflective language features like self and super and, while Ruby 1.8.7 has been obsoleted by Ruby 1.9 (YARV), the results …


Breaking Weak 1024-Bit Rsa Keys Using Cuda, Kerry Scharfglass, Darrin Weng, Joseph White, Christopher Lupo Dec 2012

Breaking Weak 1024-Bit Rsa Keys Using Cuda, Kerry Scharfglass, Darrin Weng, Joseph White, Christopher Lupo

Computer Science and Software Engineering

An exploit involving the greatest common divisor (GCD) of RSA moduli was recently discovered [1]. This paper presents a tool that can efficiently and completely compare a large number of 1024-bit RSA public keys, and identify any keys that are susceptible to this weakness. NVIDIA's graphics processing units (GPU) and the CUDA massively-parallel programming model are powerful tools that can be used to accelerate this tool. Our method using CUDA has a measured performance speedup of 27.5 compared to a sequential CPU implementation, making it a more practical method to compare large sets of keys. A computation for finding GCDs …


Data Integration: A Case Study In The Financial Services Industry, Louis Epie Dec 2012

Data Integration: A Case Study In The Financial Services Industry, Louis Epie

Regis University Student Publications (comprehensive collection)

Current economic conditions result in banks participating in multiple mergers and acquisitions. This results in banks inheriting silo and heterogeneous systems. For banks to remain competitive, they must create a strategy to integrate data from these acquired systems in a dynamic, efficient, and consumable manner. This research considers a case study of a large financial services company that has successfully integrated data from different sources. In addition this research investigates endeavors that experts in the field have undertaken to develop architectures that address the problems with data integration and appropriate solutions.


Automatic Classification Of Epilepsy Lesions, Junwei Sun Dec 2012

Automatic Classification Of Epilepsy Lesions, Junwei Sun

Electronic Thesis and Dissertation Repository

Epilepsy is a common and diverse set of chronic neurological disorders characterized by seizures. Epileptic seizures result from abnormal, excessive or hypersynchronous neuronal activity in the brain. Seizure types are organized firstly according to whether the source of the seizure within the brain is localized or distributed. In this work, our objective is to validate the use of MRI (Magnetic Resonance Imaging) for localizing seizure focus for improved surgical planning. We apply computer vision and machine learning techniques to tackle the problem of epilepsy lesion classification. First datasets of digitized histology images from brain cortexes of different patients are obtained …


A Conceptlink Graph For Text Structure Mining, Rowena Chau, Ah Chung Tsoi, Markus Hagenbuchner, Vincent Lee Dec 2012

A Conceptlink Graph For Text Structure Mining, Rowena Chau, Ah Chung Tsoi, Markus Hagenbuchner, Vincent Lee

Dr Markus Hagenbuchner

Most text mining methods are based on representing documents using a vector space model, commonly known as a bag of word model, where each document is modeled as a linear vector representing the occurrence of independent words in the text corpus. It is well known that using this vector-based representation, important information, such as semantic relationship among concepts, is lost. This paper proposes a novel text representation model called ConceptLink graph. The ConceptLink graph does not only represent the content of the document, but also captures some of its underlying semantic structure in terms of the relationships among concepts. The …


Computational Capabilities Of Graph Neural Networks, Franco Scarselli, Marco Gori, Ah Chung Tsoi, Markus Hagenbuchner, Gabriele Monfardini Dec 2012

Computational Capabilities Of Graph Neural Networks, Franco Scarselli, Marco Gori, Ah Chung Tsoi, Markus Hagenbuchner, Gabriele Monfardini

Dr Markus Hagenbuchner

In this paper, we will consider the universal approximation properties of a recently introduced neural network model called graph neural network (GNN) which can be used to process structured data inputs, e.g. acyclic graph, cyclic graph, directed or un-directed graphs. This class of neural networks implements a function (G, n) 2 IRm that maps a graph Gand one of its nodes n onto an m-dimensional Euclidean space. We characterize the functions that can be approximated by GNNs, in probability, up to any prescribed degree of precision. This set contains the maps that satisfy a property, called preservation of the unfolding …


The Graph Neural Network Model, Franco Scarselli, Marco Gori, Ah Chung Tsoi, Markus Hagenbuchner, Gabriele Monfardini Dec 2012

The Graph Neural Network Model, Franco Scarselli, Marco Gori, Ah Chung Tsoi, Markus Hagenbuchner, Gabriele Monfardini

Dr Markus Hagenbuchner

Many underlying relationships among data in several areas of science and engineering, e.g. computer vision, molecular chemistry, molecular biology, pattern recognition, data mining, can be represented in terms of graphs. In this paper, we propose a new neural network model, called graph neural network (GNN) model, that extends existing neural network methods for processing the data represented in the graph domain. This GNN model, which can directly process most of the practically useful types of graphs, e.g. acyclic, cyclic, directed, un-directed, implements a transduction function $\tau(\BG,n)\in\R^m$ that maps a graph $\BG$ and one of its nodes $n$ into an m-dimensional …


Ranking Attack Graphs With Graph Neural Networks, Liang Lu, Rei Safavi-Naini, Markus Hagenbuchner, Willy Susilo, Jeffrey Horton, Sweah Liang Yong, Ah Chung Tsoi Dec 2012

Ranking Attack Graphs With Graph Neural Networks, Liang Lu, Rei Safavi-Naini, Markus Hagenbuchner, Willy Susilo, Jeffrey Horton, Sweah Liang Yong, Ah Chung Tsoi

Dr Markus Hagenbuchner

Network security analysis based on attack graphs has been applied extensively in recent years. The ranking of nodes in an attack graph is an important step towards analyzing network security. This paper proposes an alternative attack graph ranking scheme based on a recent approach to machine learning in a structured graph domain, namely, Graph Neural Networks (GNNs). Evidence is presented in this paper that the GNN is suitable for the task of ranking attack graphs by learning a ranking function from examples and generalizes the function to unseen possibly noisy data, thus showing that the GNN provides an effective alternative …


Data Curation Is For Everyone! The Case For Master's And Baccalaureate Institutional Engagement With Data Curation, Yasmeen Shorish Dec 2012

Data Curation Is For Everyone! The Case For Master's And Baccalaureate Institutional Engagement With Data Curation, Yasmeen Shorish

Yasmeen Shorish

This article describes the fundamental challenges to data curation, how these challenges may be compounded for smaller institutions, and how data management is an essential and manageable component of data curation. Data curation is often discussed within the confines of large, research universities. As a result, master’s and baccalaureate institutions may be left with the impression that they cannot engage with data curation. However, by proactively engaging with faculty, libraries of all sizes can build closer relationships and help educate faculty on data documentation and organization best practices. Experiences from one master’s comprehensive institution as it engages with data management …


Automatic Foreground Initialization For Binary Image Segmentation, Wei Li Dec 2012

Automatic Foreground Initialization For Binary Image Segmentation, Wei Li

Electronic Thesis and Dissertation Repository

Foreground segmentation is a fundamental problem in computer vision. A popular approach for foreground extraction is through graph cuts in energy minimization framework. Most existing graph cuts based image segmentation algorithms rely on user’s initialization. In this work, we aim to find an automatic initialization for graph cuts. Unlike many previous methods, no additional training dataset is needed. Collecting a training set is not only expensive and time consuming, but it also may bias the algorithm to the particular data distribution of the collected dataset. We assume that the foreground differs significantly from the background in some unknown feature space …


An Outcome-Based Approach For Ensuring Regulatory Compliance Of Business Processes, Quanjun Yin Dec 2012

An Outcome-Based Approach For Ensuring Regulatory Compliance Of Business Processes, Quanjun Yin

Electronic Thesis and Dissertation Repository

In service industries, such as healthcare, catering, tourism, etc., there exist regulations that require organisations’ service comply with the regulations. More and more regulations in the service sector are, or are aimed to be, outcome-focused regulations. An outcome prescribed in the regulation is what users should experience or achieve when the regulated business processes are compliant. Service providers need to proactively ensure that the outcomes specified in the regulations have been achieved prior to conducting the relevant part of the business or prior to inspectors discovering noncompliance. Current approaches check system requirements or business processes, not outcomes, against regulations and …


Hybrid Solvers For The Boolean Satisfiability Problem: An Exploration, Nicole Nelson Dec 2012

Hybrid Solvers For The Boolean Satisfiability Problem: An Exploration, Nicole Nelson

Theses and Dissertations

The Boolean Satisfiability problem (SAT) is one of the most extensively researched NP-complete problems in Computer Science. This thesis focuses on the design of feasible solvers for this problem. A SAT problem instance is a formula in propositional logic. A SAT solver attempts to find a solution for the formula. Our research focuses on a newer solver paradigm, hybrid solvers, where two solvers are combined in order to gain the benefits from both solvers in the search for a solution. Our hybrid solver, AmbSAT, combines two well-known solvers: the systematic Davis-Putnam-Logemann-Loveland solver (DPLL) and the stochastic WalkSAT solver. AmbSAT's design …


Charateristics And Impact Of Interpersonal Conflicts On Requirements Risks, Avinder Walia Dec 2012

Charateristics And Impact Of Interpersonal Conflicts On Requirements Risks, Avinder Walia

Electronic Thesis and Dissertation Repository

Interpersonal conflicts in software projects have an impact on project’s success, product’s quality, team’s performance, etc. However, in Requirements Engineering (RE), there is dearth of research on this topic; previous research has focused largely on conflicts among requirements. We conducted a case study of an industrial project to determine the characteristics (e.g., type, severity, conflict management styles, etc.) and impact of interpersonal conflicts rooted in RE (RE-Conflicts), on project risks associated with requirements (e..g., inadequately identified requirements, incorrect requirements, etc). The findings show that the conflicts over administrative procedures (47%) had the highest frequency count. The highest number of …


A Model For Coherent Distributed Systems, Robert L. Brown, Peter J. Denning, Walter F. Tichy Dec 2012

A Model For Coherent Distributed Systems, Robert L. Brown, Peter J. Denning, Walter F. Tichy

Dr Robert Brown

No abstract provided.


Automatic, Remote Status Lights For Vax Unix, Douglas E. Comer, Robert L. Brown Dec 2012

Automatic, Remote Status Lights For Vax Unix, Douglas E. Comer, Robert L. Brown

Dr Robert Brown

No abstract provided.


Should Distributed Systems Be Hidden?, Peter J. Denning, Robert L. Brown Dec 2012

Should Distributed Systems Be Hidden?, Peter J. Denning, Robert L. Brown

Dr Robert Brown

No abstract provided.


P2cp: A New Cloud Storage Model To Enhance Performance Of Cloud Services, Zhe Sun, Jun Shen, Ghassan Beydoun Dec 2012

P2cp: A New Cloud Storage Model To Enhance Performance Of Cloud Services, Zhe Sun, Jun Shen, Ghassan Beydoun

Associate Professor Ghassan Beydoun

This paper presents a storage model named Peer to Cloud and Peer (P2CP). Assuming that the P2CP model follows the Poisson process or Little’s law, we prove that the speed and availability of P2CP is generally better than that of the pure Peer to Peer (P2P) model, the Peer to Server, Peer (P2SP) model or the cloud model. A key feature of our P2CP is that it has three data transmission tunnels: the cloud-user data transmission tunnel, the clients’ data transmission tunnel, and the common data transmission tunnel. P2CP uses the cloud storage system as a common storage system. When …


A Guide To Documenting Software Design For Maximum Software Portability For Software Defined Radios, Joseph Snively Dec 2012

A Guide To Documenting Software Design For Maximum Software Portability For Software Defined Radios, Joseph Snively

Regis University Student Publications (comprehensive collection)

The use of software defined communications systems is growing incredibly fast. The field of software engineering as a discipline has not adequately addressed the subject of software portability which makes large and costly software development efforts less ready to port to future platforms. By understanding the causes of portability problems, they can either be avoided altogether in development or very well documented so that they are easier to overcome in future efforts. Literature, case studies, and surveys are used to collect opinions and information about large software programs where portability is a desirable characteristic in order to best establish the …


Symbolic Model-Checking Of Stateful Timed Csp Using Bdd And Digitization, Truong Khanh Nguyen, Jun Sun, Yang Liu, Jin Song Dong Dec 2012

Symbolic Model-Checking Of Stateful Timed Csp Using Bdd And Digitization, Truong Khanh Nguyen, Jun Sun, Yang Liu, Jin Song Dong

Research Collection School Of Computing and Information Systems

Stateful Timed CSP has been recently proposed to model (and verify) hierarchical real-time systems. It is an expressive modeling language which combines data structure/operations, complicated control flows (modeled using compositional process operators adopted from Timed CSP), and real-time requirements like deadline and within. It has been shown that Stateful Timed CSP is equivalent to closed timed automata with silent transitions, which implies that the timing constraints of Stateful Timed CSP can be captured using explicit tick events, through digitization. In order to tackle the state space explosion problem, we develop a BDD-based symbolic model checking approach to verify Stateful Timed …


Improvements On Seeding Based Protein Sequence Similarity Search, Weiming Li Dec 2012

Improvements On Seeding Based Protein Sequence Similarity Search, Weiming Li

Electronic Thesis and Dissertation Repository

The primary goal of bioinformatics is to increase an understanding in the biology of organisms. Computational, statistical, and mathematical theories and techniques have been developed on formal and practical problems that assist to achieve this primary goal. For the past three decades, the primary application of bioinformatics has been biological data analysis. The DNA or protein sequence similarity search is perhaps the most common, yet vitally important task for analyzing biological data.

The sequence similarity search is a process of finding optimal sequence alignments. On the theoretical level, the problem of sequence similarity search is complex. On the applicational level, …


Error Correction In Next Generation Dna Sequencing Data, Michael Z. Molnar Dec 2012

Error Correction In Next Generation Dna Sequencing Data, Michael Z. Molnar

Electronic Thesis and Dissertation Repository

Motivation: High throughput Next Generation Sequencing (NGS) technologies can sequence the genome of a species quickly and cheaply. Errors that are introduced by NGS technologies limit the full potential of the applications that rely on their data. Current techniques used to correct these errors are not sufficient, and a more efficient and accurate program is needed to correct errors.

Results: We have designed and implemented RACER (Rapid Accurate Correction of Errors in Reads), an error correction program that targets the Illumina genome sequencer, which is currently the dominant NGS technology. RACER combines advanced data structures with an intricate analysis of …


Security Analysis Of Two Signcryption Schemes, Guilin Wang, Robert H. Deng, Dongjin Kwak, Sangjae Moon Dec 2012

Security Analysis Of Two Signcryption Schemes, Guilin Wang, Robert H. Deng, Dongjin Kwak, Sangjae Moon

Dr Guilin Wang

Signcryption is a new cryptographic primitive that performs signing and encryption simultaneously, at a cost significantly lower than that required by the traditional signature-then-encryption approach. In this paper, we present a security analysis of two such schemes: the Huang-Chang convertible signcryption scheme, and the Kwak-Moon group signcryption scheme. Our results show that both schemes are insecure. Specifically, the Huang-Chang scheme fails to provide confidentiality, while the Kwak-Moon scheme does not satisfy the properties of unforgeability, coalition-resistance, and traceability.


Comments On "A Practical (T, N) Threshold Proxy Signature Scheme Based On The Rsa Cryptosystem", Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng Dec 2012

Comments On "A Practical (T, N) Threshold Proxy Signature Scheme Based On The Rsa Cryptosystem", Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng

Dr Guilin Wang

In a (t, n) threshold proxy signature scheme based on RSA, any t or more proxy signers can cooperatively generate a proxy signature while t-1 or fewer of them can't do it. The threshold proxy signature scheme uses the RSA cryptosystem to generate the private and the public key of the signers. In this article, we discuss the implementation and comparison of some threshold proxy signature schemes that are based on the RSA cryptosystem. Comparison is done on the basis of time complexity, space complexity and communication overhead. We compare the performance of four schemes: Hwang et al., Wen et …