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Full-Text Articles in Physical Sciences and Mathematics

Secure Integer Comparisons Using The Homomorphic Properties Of Prime Power Subgroups, Rhys A. Carlton Aug 2017

Secure Integer Comparisons Using The Homomorphic Properties Of Prime Power Subgroups, Rhys A. Carlton

Electronic Thesis and Dissertation Repository

Secure multi party computation allows two or more parties to jointly compute a function under encryption without leaking information about their private inputs. These secure computations are vital in many fields including law enforcement, secure voting and bioinformatics because the privacy of the information is of paramount importance.

One common reference problem for secure multi party computation is the Millionaires' problem which was first introduced by Turing Award winner Yao in his paper "Protocols for secure computation". The Millionaires' problem considers two millionaires who want to know who is richer without disclosing their actual worth.

There are public-key cryptosystems that …


Machs: Mitigating The Achilles Heel Of The Cloud Through High Availability And Performance-Aware Solutions, Manar Jammal Apr 2017

Machs: Mitigating The Achilles Heel Of The Cloud Through High Availability And Performance-Aware Solutions, Manar Jammal

Electronic Thesis and Dissertation Repository

Cloud computing is continuously growing as a business model for hosting information and communication technology applications. However, many concerns arise regarding the quality of service (QoS) offered by the cloud. One major challenge is the high availability (HA) of cloud-based applications. The key to achieving availability requirements is to develop an approach that is immune to cloud failures while minimizing the service level agreement (SLA) violations. To this end, this thesis addresses the HA of cloud-based applications from different perspectives. First, the thesis proposes a component’s HA-ware scheduler (CHASE) to manage the deployments of carrier-grade cloud applications while maximizing their …


Practical Attacks On Cryptographically End-To-End Verifiable Internet Voting Systems, Nicholas Chang-Fong Apr 2017

Practical Attacks On Cryptographically End-To-End Verifiable Internet Voting Systems, Nicholas Chang-Fong

Electronic Thesis and Dissertation Repository

Cryptographic end-to-end verifiable voting technologies concern themselves with the provision of a more trustworthy, transparent, and robust elections. To provide voting systems with more transparency and accountability throughout the process while preserving privacy which allows voters to express their true intent.

Helios Voting is one of these systems---an online platform where anyone can easily host their own cryptographically end-to-end verifiable election, aiming to bring verifiable voting to the masses. Helios does this by providing explicit cryptographic checks that an election was counted correctly, checks that any member of the public can independently verify. All of this while still protecting one …


Metafork: A Compilation Framework For Concurrency Models Targeting Hardware Accelerators, Xiaohui Chen Mar 2017

Metafork: A Compilation Framework For Concurrency Models Targeting Hardware Accelerators, Xiaohui Chen

Electronic Thesis and Dissertation Repository

Parallel programming is gaining ground in various domains due to the tremendous computational power that it brings; however, it also requires a substantial code crafting effort to achieve performance improvement. Unfortunately, in most cases, performance tuning has to be accomplished manually by programmers. We argue that automated tuning is necessary due to the combination of the following factors. First, code optimization is machine-dependent. That is, optimization preferred on one machine may be not suitable for another machine. Second, as the possible optimization search space increases, manually finding an optimized configuration is hard. Therefore, developing new compiler techniques for optimizing applications …


Analysis Of 3d Cone-Beam Ct Image Reconstruction Performance On A Fpga, Devin Held Dec 2016

Analysis Of 3d Cone-Beam Ct Image Reconstruction Performance On A Fpga, Devin Held

Electronic Thesis and Dissertation Repository

Efficient and accurate tomographic image reconstruction has been an intensive topic of research due to the increasing everyday usage in areas such as radiology, biology, and materials science. Computed tomography (CT) scans are used to analyze internal structures through capture of x-ray images. Cone-beam CT scans project a cone-shaped x-ray to capture 2D image data from a single focal point, rotating around the object. CT scans are prone to multiple artifacts, including motion blur, streaks, and pixel irregularities, therefore must be run through image reconstruction software to reduce visual artifacts. The most common algorithm used is the Feldkamp, Davis, and …


Regulatory Compliance-Oriented Impediments And Associated Effort Estimation Metrics In Requirements Engineering For Contractual Systems Engineering Projects, Md Rashed I. Nekvi Dec 2016

Regulatory Compliance-Oriented Impediments And Associated Effort Estimation Metrics In Requirements Engineering For Contractual Systems Engineering Projects, Md Rashed I. Nekvi

Electronic Thesis and Dissertation Repository

Large-scale contractual systems engineering projects often need to comply with a myriad of government regulations and standards as part of contractual fulfillment. A key activity in the requirements engineering (RE) process for such a project is to elicit appropriate requirements from the regulations and standards that apply to the target system. However, there are impediments in achieving compliance due to such factors as: the voluminous contract and its high-level specifications, large number of regulatory documents, and multiple domains of the system. Little empirical research has been conducted on developing a shared understanding of the compliance-oriented complexities involved in such projects, …


Automatic Fracture Orientation Extraction From Sfm Point Clouds, Jon Kissi Oct 2016

Automatic Fracture Orientation Extraction From Sfm Point Clouds, Jon Kissi

Electronic Thesis and Dissertation Repository

Geology seeks to understand the history of the Earth and its surface processes through charac- terisation of surface formations and rock units. Chief among the geologists’ tools are rock unit orientation measurements, such as Strike, Dip and Dip Direction. These allow an understanding of both surface and sub-structure on both the local and macro scale.

Although the way these techniques can be used to characterise geology are well understood, the need to collect these measurements by hand adds time and expense to the work of the geologist, precludes spontaneity in field work, and coverage is limited to where the geologist …


Agora: A Knowledge Marketplace For Machine Learning, Mauro Ribeiro Aug 2016

Agora: A Knowledge Marketplace For Machine Learning, Mauro Ribeiro

Electronic Thesis and Dissertation Repository

More and more data are becoming part of people's lives. With the popularization of technologies like sensors, and the Internet of Things, data gathering is becoming possible and accessible for users. With these data in hand, users should be able to extract insights from them, and they want results as soon as possible. Average users have little or no experience in data analytics and machine learning and are not great observers who can collect enough data to build their own machine learning models. With large quantities of similar data being generated around the world and many machine learning models being …


Climbing Up Cloud Nine: Performance Enhancement Techniques For Cloud Computing Environments, Mohamed Abusharkh Jul 2016

Climbing Up Cloud Nine: Performance Enhancement Techniques For Cloud Computing Environments, Mohamed Abusharkh

Electronic Thesis and Dissertation Repository

With the transformation of cloud computing technologies from an attractive trend to a business reality, the need is more pressing than ever for efficient cloud service management tools and techniques. As cloud technologies continue to mature, the service model, resource allocation methodologies, energy efficiency models and general service management schemes are not yet saturated. The burden of making this all tick perfectly falls on cloud providers. Surely, economy of scale revenues and leveraging existing infrastructure and giant workforce are there as positives, but it is far from straightforward operation from that point. Performance and service delivery will still depend on …


Feature Encoding Strategies For Multi-View Image Classification, Kyle Doerr Jan 2016

Feature Encoding Strategies For Multi-View Image Classification, Kyle Doerr

Electronic Thesis and Dissertation Repository

Machine vision systems can vary greatly in size and complexity depending on the task at hand. However, the purpose of inspection, quality and reliability remains the same. This work sets out to bridge the gap between traditional machine vision and computer vision. By applying powerful computer vision techniques, we are able to achieve more robust solutions in manufacturing settings. This thesis presents a framework for applying powerful new image classification techniques used for image retrieval in the Bag of Words (BoW) framework. In addition, an exhaustive evaluation of commonly used feature pooling approaches is conducted with results showing that spatial …


Dynamically Testing Graphical User Interfaces, Santo Carino Jan 2016

Dynamically Testing Graphical User Interfaces, Santo Carino

Electronic Thesis and Dissertation Repository

Software test generation for GUIs is a hard problem. The goal of this thesis is to investigate different methods for dynamically generating tests for GUIs. We introduce the concept of an event-pair graph, which is used to represent and measure test suites, and show how it can be used to generate tests and measure GUI coverage. Before we can begin generating tests, we first want to determine which is better: a small test suite with a few long tests or a large test suite with many short tests. Therefore, we designed and conducted a study to determine which is more …


Generating Invalid Input Strings For Software Testing, Benjamin D. Revington Aug 2015

Generating Invalid Input Strings For Software Testing, Benjamin D. Revington

Electronic Thesis and Dissertation Repository

Grammar-based testing has interested the academic community for decades, but little work has been done with regards to testing with invalid input strings. For our research, we generated LR parse tables from grammars. We then generated valid and invalid strings based on coverage of these tables. We evaluated the effectiveness of these strings in terms of code coverage and fault detection by inputting them to subject programs which accept input based on the grammars. For a baseline, we then compared the effectiveness of these strings to a more general approach where the tokens making up each string are chosen randomly. …


A Software Design Pattern Based Approach To Auto Dynamic Difficulty In Video Games, Muhammad Iftekher Chowdhury Sep 2014

A Software Design Pattern Based Approach To Auto Dynamic Difficulty In Video Games, Muhammad Iftekher Chowdhury

Electronic Thesis and Dissertation Repository

From the point of view of skill levels, reflex speeds, hand-eye coordination, tolerance for frustration, and motivations, video game players may vary drastically. Auto dynamic difficulty (ADD) in video games refers to the technique of automatically adjusting different aspects of a video game in real time, based on the player’s ability and emergence factors in order to provide the optimal experience to users from such a large demography and increase replay value. In this thesis, we describe a collection of software design patterns for enabling auto dynamic difficulty in video games. We also discuss the benefits of a design pattern …


Intents-Based Service Discovery And Integration, Cheng Zheng Sep 2014

Intents-Based Service Discovery And Integration, Cheng Zheng

Electronic Thesis and Dissertation Repository

With the proliferation of Web services, when developing a new application, it makes sense to seek and leverage existing Web services rather than implementing the corresponding components from scratch. Therefore, significant research efforts have been devoted to the techniques for service discovery and integration. However, most of the existing techniques are based on the ternary participant classification of the Web service architecture which only takes into consideration the involvement of service providers, service brokers, and application developers. The activities of application end users are usually ignored.

This thesis presents an Intents-based service discovery and integration approach at the conceptual level …


On The Interoperability Of Programming Languages Based On The Fork-Join Parallelism Model, Sushek Shekar Dec 2013

On The Interoperability Of Programming Languages Based On The Fork-Join Parallelism Model, Sushek Shekar

Electronic Thesis and Dissertation Repository

This thesis describes the implementation of MetaFork, a meta-language for concurrency platforms targeting multicore architectures. First of all, MetaFork is a multithreaded language based on the fork-join model of concurrency: it allows the programmer to express parallel algorithms assuming that tasks are dynamically scheduled at run-time. While MetaFork makes no assumption about the run-time system, it formally defines the serial C-elision of a MetaFork program. In addition, MetaFork is a suite of source-to-source compilers permitting the automatic translation of multithreaded programs between programming languages based on the fork-join model. Currently, this compilation framework supports the OpenMP and CilkPlus concurrency platforms. …


Missing Requirements Information And Its Impact On Software Architectures: A Case Study, Md Rounok Salehin Dec 2013

Missing Requirements Information And Its Impact On Software Architectures: A Case Study, Md Rounok Salehin

Electronic Thesis and Dissertation Repository

[Context & motivation] In the development of large, software-intensive systems, the system’s requirements are seldom, if ever, concluded upon prior to commencing with systems architecture. Research shows that, in order to manage development and domain complexities, instances of requirements engineering (RE) and systems architecting (SA) processes tend to inter-weave. [Question/problem] However, missing requirements information can cause one to create (or recreate) the needed information during different SA activities. While backtracking in the software development process is known to be costly, the costs associated with missing requirements in the SA process have not been investigated empirically. [Principal ideas/results] We …


A Modular Approach To The Development Of Interactive Augmented Reality Applications., Nelson J. Andre Dec 2013

A Modular Approach To The Development Of Interactive Augmented Reality Applications., Nelson J. Andre

Electronic Thesis and Dissertation Repository

Augmented reality (AR) technologies are becoming increasingly popular as a result of the increase in the power of mobile computing devices. Emerging AR applications have the potential to have an enormous impact on industries such as education, healthcare, research, training and entertainment. There are currently a number of augmented reality toolkits and libraries available for the development of these applications; however, there is currently no standard tool for development. In this thesis we propose a modular approach to the organization and development of AR systems in order to enable the creation novel AR experiences. We also investigate the incorporation of …


Redesign Of Johar: A Framework For Developing Accessible Applications, Oladapo Oyebode Dec 2013

Redesign Of Johar: A Framework For Developing Accessible Applications, Oladapo Oyebode

Electronic Thesis and Dissertation Repository

As the population of disabled people continues to grow, designing accessible applications is still a challenge, since most applications are incompatible with assistive technologies used by disabled people to interact with the computer. This accessibility issue is usually caused by the reluctance of software engineers or developers to include complete accessibility features in their applications, which in turn is often due to the extra cost and development effort required to dynamically adapt applications to a wide range of disabilities. Our aim to resolve accessibility issues led to the design and implementation of the "Johar" framework, which facilitates the development of …


Collaborative Policy-Based Autonomic Management In Iaas Clouds, Omid Mola Sep 2013

Collaborative Policy-Based Autonomic Management In Iaas Clouds, Omid Mola

Electronic Thesis and Dissertation Repository

With the increasing number of "machines" (either virtual or physical) in a computing environment, it is becoming harder to monitor and manage these resources. Relying on human administrators, even with tools, is expensive and the growing complexity makes management even harder. The alternative is to look for automated approaches that can monitor and manage computing resources in real time with no human intervention. One of the approaches to this problem is policy-based autonomic management. However, in large systems having one single autonomic manager to manage everything is almost impossible. Therefore, multiple autonomic managers will be needed and these will need …


Reliability Models Applied To Smartphone Applications, Sonia Meskini Aug 2013

Reliability Models Applied To Smartphone Applications, Sonia Meskini

Electronic Thesis and Dissertation Repository

Smartphones have become the most used electronic devices. They carry out most of the functionalities of desktops, offering various useful applications that suit the user’s needs. Therefore, instead of the operator, the user has been the main controller of the device and its applications, therefore its reliability has become an emergent requirement. As a first step, based on collected smartphone applications failure data, we investigated and evaluated the efficacy of Software Reliability Growth Models (SRGMs) when applied to these smartphone data in order to check whether they achieve the same accuracy as in the desktop/laptop area. None of the selected …


Maps Of Lessons Learnt In Requirements Engineering, Ibtehal Noorwali Jun 2013

Maps Of Lessons Learnt In Requirements Engineering, Ibtehal Noorwali

Electronic Thesis and Dissertation Repository

Both researchers and practitioners have emphasized the importance of learning from past experiences and its consequential impact on project time, cost, and quality. However, from the survey we conducted of requirements engineering (RE) practitioners, over 70\% of the respondents stated that they seldom use RE lessons in the RE process, though 85\% of these would use such lessons if readily available. Our observation, however, is that RE lessons are scattered, mainly implicitly, in the literature and practice, which obviously, does not help the situation. We, therefore, present ``maps” of RE lessons which would highlight weak (dark) and strong (bright) areas …


Localizing State-Dependent Faults Using Associated Sequence Mining, Shaimaa Ali May 2013

Localizing State-Dependent Faults Using Associated Sequence Mining, Shaimaa Ali

Electronic Thesis and Dissertation Repository

In this thesis we developed a new fault localization process to localize faults in object oriented software. The process is built upon the "Encapsulation'' principle and aims to locate state-dependent discrepancies in the software's behavior. We experimented with the proposed process on 50 seeded faults in 8 subject programs, and were able to locate the faulty class in 100% of the cases when objects with constant states were taken into consideration, while we missed 24% percent of the faults when these objects were not considered. We also developed a customized data mining technique "Associated sequence mining'' to be used in …


An Architecture For Believable Socially Aware Agents, Arvand Dorgoly Apr 2013

An Architecture For Believable Socially Aware Agents, Arvand Dorgoly

Electronic Thesis and Dissertation Repository

The main focus of this thesis is to solve the believability problem in video game agents by integrating necessary psychological and sociological foundations by means of role based architecture. Our design agent also has the capability to reason and predict the decisions of other actors by using its own mental model. The agent has a separate mental model for every actor.


Integrated Development And Parallelization Of Automated Dicentric Chromosome Identification Software To Expedite Biodosimetry Analysis, Yanxin Li Apr 2013

Integrated Development And Parallelization Of Automated Dicentric Chromosome Identification Software To Expedite Biodosimetry Analysis, Yanxin Li

Electronic Thesis and Dissertation Repository

Manual cytogenetic biodosimetry lacks the ability to handle mass casualty events. We present an automated dicentric chromosome identification (ADCI) software utilizing parallel computing technology. A parallelization strategy combining data and task parallelism, as well as optimization of I/O operations, has been designed, implemented, and incorporated in ADCI. Experiments on an eight-core desktop show that our algorithm can expedite the process of ADCI by at least four folds. Experiments on Symmetric Computing, SHARCNET, Blue Gene/Q multi-processor computers demonstrate the capability of parallelized ADCI to process thousands of samples for cytogenetic biodosimetry in a few hours. This increase in speed underscores the …


Fuzzy Expert-Cocomo Risk Assessment And Effort Contingency Model In Software Project Management, Ekananta Manalif Mar 2013

Fuzzy Expert-Cocomo Risk Assessment And Effort Contingency Model In Software Project Management, Ekananta Manalif

Electronic Thesis and Dissertation Repository

Software development can be considered to be the most uncertain project when compared to other types of projects due to the uncertainty in the customer requirements, the complexity of the process, and the intangible nature of the product. In order to increase the likelihood of success in managing a software project, the project manager(s) must invest more time and effort in the project planning phase. The two main activities in project planning phase are effort estimation and risk management which has to be executed together because the accuracy of the effort estimation is highly dependent on the size and nature …


Multi-Point Stride Coverage: A New Genre Of Test Coverage Criteria, Mohammad Mahdi Hassan Feb 2013

Multi-Point Stride Coverage: A New Genre Of Test Coverage Criteria, Mohammad Mahdi Hassan

Electronic Thesis and Dissertation Repository

We introduce a family of coverage criteria, called Multi-Point Stride Coverage (MPSC). MPSC generalizes branch coverage to coverage of tuples of branches taken from the execution sequence of a program. We investigate its potential as a replacement for dataflow coverage, such as def-use coverage. We find that programs can be instrumented for MPSC easily, that the instrumentation usually incurs less overhead than that for def-use coverage, and that MPSC is comparable in usefulness to def-use in predicting test suite effectiveness. We also find that the space required to collect MPSC can be predicted from the number of branches in the …


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 …


Generating Log File Analyzers, Ilse Leal Aulenbacher Aug 2012

Generating Log File Analyzers, Ilse Leal Aulenbacher

Electronic Thesis and Dissertation Repository

Software testing is a crucial part of the software development process, because it helps developers ensure that the software works correctly and according to stakehold- ers’ requirements and specifications. Faulty or problematic software can cause huge financial losses. Automation of testing tasks can have a positive impact on software development, by reducing costs and minimizing human error. Software testing can be divided into three tasks: choosing test cases, running test cases on the software under test (SUT) and evaluating the test results. To evaluate test results, testers need to examine the output of the SUT to determine if it performed …


Security On Medical Wireless Sensor Networks, Eric D. Southern Aug 2012

Security On Medical Wireless Sensor Networks, Eric D. Southern

Electronic Thesis and Dissertation Repository

Wireless technology is fast becoming a very important tool for all aspects of communication. An area that lacks a strong implementation for wireless communication is the medical field. Wireless systems could be used by clinicians to be better able to diagnose and monitor patients. The reason behind the lack of adoption in healthcare is due to the need to meet the legislated and perceived requirements of security and privacy when dealing with clinical information. The current methods of wireless authentication are investigated and an existing issue in mobile networks is described and solved with two novel solutions; one solution within …


Models, Techniques, And Metrics For Managing Risk In Software Engineering, Andriy Miranskyy Jun 2011

Models, Techniques, And Metrics For Managing Risk In Software Engineering, Andriy Miranskyy

Electronic Thesis and Dissertation Repository

The field of Software Engineering (SE) is the study of systematic and quantifiable approaches to software development, operation, and maintenance. This thesis presents a set of scalable and easily implemented techniques for quantifying and mitigating risks associated with the SE process. The thesis comprises six papers corresponding to SE knowledge areas such as software requirements, testing, and management. The techniques for risk management are drawn from stochastic modeling and operational research.

The first two papers relate to software testing and maintenance. The first paper describes and validates novel iterative-unfolding technique for filtering a set of execution traces relevant to a …