Computer Engineering Commons^™

Optimal Spectrum Sensing And Channel Search Strategies For Cognitive Radio Systems: Algorithms, Analysis, And Real-Time Implementation, Raied Caromi

Theses and Dissertations

Spurred on by the ever increasing demand for bandwidth and the shortage of radio spectrum, researchers are faced with numerous challenges to advance the new technologies. At the same time, spectrum is under-utilized and not fully exploited most of the time in most places. Cognitive radio (CR) is an emerging technology that offers a novel approach to solve the problem of spectrum under-utilization. Specifically, CR offers an approach to share the spectrum through dynamic spectrum access (DSA). In particular, the secondary users (SUs) are allowed to use the communication system without interrupting the primary users (PUs). Spectrum sensing is the …

The Theory And Application Of Privacy-Preserving Computation, Michael R. Clark

Theses and Dissertations

Privacy is a growing concern in the digital world as more information becomes digital every day. Often the implications of how this information could be exploited for nefarious purposes are not explored until after the fact. The public is becoming more concerned about this. This dissertation introduces a new paradigm for tackling the problem, namely, transferable multiparty computation (T-MPC). T-MPC builds upon existing multiparty computation work yet allows some additional flexibility in the set of participants. T-MPC is orders of magnitude more efficient for certain applications. This greatly increases the scalability of the sizes of networks supported for privacy-preserving computation.

Git As An Encrypted Distributed Version Control System, Russell G. Shirey

Theses and Dissertations

This thesis develops and presents a secure Git implementation, Git Virtual Vault (GV2), for users of Git to work on sensitive projects with repositories located in unsecure distributed environments, such as in cloud computing. This scenario is common within the Department of Defense, as much work is of a sensitive nature. In order to provide security to Git, additional functionality is added for confidentiality and integrity protection. This thesis examines existing Git encryption implementations and baselines their performance compared to unencrypted Git. Real-world Git repositories are examined to characterize typical Git usage and determine if the existing Git encryption implementations …

Leveraging Human Insights By Combining Multi-Objective Optimization With Interactive Evolution, Joshua R. Christman

Theses and Dissertations

Deceptive fitness landscapes are a growing concern for evolutionary computation. Recent work has shown that combining human insights with short-term evolution has a synergistic effect that accelerates the discovery of solutions. While humans provide rich insights, they fatigue easily. Previous work reduced the number of human evaluations by evolving a diverse set of candidates via intermittent searches for novelty. While successful at evolving solutions for a deceptive maze domain, this approach lacks the ability to measure what the human evaluator identifies as important. The key insight here is that multi-objective evolutionary algorithms foster diversity, serving as a surrogate for novelty, …

Fpga Accelerated Discrete-Surf For Real-Time Homography Estimation, Andrew C. Leighner

Theses and Dissertations

This paper describes our hardware accelerated, FPGA implementation of SURF, named Discrete SURF, to support real-time homography estimation for close range aerial navigation. The SURF algorithm provides feature matches between a model and a scene which can be used to find the transformation between the camera and the model. Previous implementations of SURF have partially employed FPGAs to accelerate the feature detection stage of upright only image comparisons. We extend the work of previous implementations by providing an FPGA implementation that allows rotation during image comparisons in order to facilitate aerial navigation. We also expand beyond feature detection as the …

Counter Weapon Control, Brian J. Roadruck

Theses and Dissertations

In this work, pursuit-evasion differential game theory is applied to the target defense scenario. The targets, attackers, and the defenders positional information is assumed to be known to the players. With positional information, a computational efficient method of strategy synthesis can be derived applying a differential game theory approach. We demonstrate that when non-optimal strategies are employed by one of the players, e.g. Line Of Sight guidance, the outcome will favor the players that employ the optimal strategy given by the solution of the pursuit-evasion differential game.

Robust Models For Operator Workload Estimation, Andrew M. Smith

Theses and Dissertations

When human-machine system operators are overwhelmed, judicious employment of automation can be beneficial. Ideally, a system which can accurately estimate current operator workload can make better choices when to employ automation. Supervised machine learning models can be trained to estimate workload in real time from operator physiological data. Unfortunately, estimating operator workload using trained models is limited: using a model trained in one context can yield poor estimation of workload in another. This research examines the utility of three algorithms (linear regression, regression trees, and Artificial Neural Networks) in terms of cross-application workload prediction. The study is conducted for a …

Characterization Of A Robotic Manipulator For Dynamic Wind Tunnel Applications, James C. Lancaster

Theses and Dissertations

The newly acquired 6-DOF Motion Test Apparatus (MTA) was installed to perform dynamic wind tunnel testing in the AFIT Low Speed Wind Tunnel. Several complex motions revealed that the overall performance of the test rig needed improvement especially during small motions. The motions exposed that further enhancements would need to be performed individually for each joint. This research effort focused on the improvement of the MTA wrist roll motor and controller using a pitch oscillation. The controller software was improved using position feedback because the MTA wrist roll motor and controller exhibited reduced signal bias and amplitude attenuation. The enhanced …

Automatic Configuration Of Programmable Logic Controller Emulators, Phillip C. Warner

Theses and Dissertations

Programmable logic controllers (PLCs), which are used to control much of the world's critical infrastructures, are highly vulnerable and exposed to the Internet. Many efforts have been undertaken to develop decoys, or honeypots, of these devices in order to characterize, attribute, or prevent attacks against Industrial Control Systems (ICS) networks. Unfortunately, since ICS devices typically are proprietary and unique, one emulation solution for a particular vendor's model will not likely work on other devices. Many previous efforts have manually developed ICS honeypots, but it is a very time intensive process. Thus, a scalable solution is needed in order to automatically …

Identification Of Employee Engagement Practices Viewed As Critical To Retention: A Cross-Generational Comparison, Sharon R. Floyd

Dissertations

Purpose. The purpose of this study was to identify the employee engagement practices that millennial IT workers perceive as important to retention. The secondary purpose of the study was to determine whether a difference exists between the engagement practices that appeal to millennial IT workers and the engagement practices that appeal to remaining IT working groups, which include the baby boomers and generation X.

Methodology. A quantitative, descriptive, survey-based research method was chosen for this study. The population included information technology workers representing three generations of working adults, including baby boomers, generation Xers, and millennials. The sample included technology workers …

Low-Power And Robust Level-Shifter With Contention Mitigation For Memory And Standalone Applications, Kenneth M. Ramclam

USF Tampa Graduate Theses and Dissertations

The scaling down of transistor sizes has imposed significant challenges in today's technology. Memories such as eDRAM, are experiencing poor retention time because of challenges such as reference voltage variation, high transistor leakage, and low cell capacitance. It can be seen that we must consider not only the first order effects, but also the second order effects to ensure we keep up with current technology trends such as Moore's law. In this thesis we explore various circuit level techniques on level shifters in order to achieve better retention time. With our research, we have addressed important design challenges and propose …

Dcms: A Data Analytics And Management System For Molecular Simulation, Meryem Berrada

USF Tampa Graduate Theses and Dissertations

Despite the fact that Molecular Simulation systems represent a major research tool in multiple scientific and engineering fields, there is still a lack of systems for effective data management and fast data retrieval and processing. This is mainly due to the nature of MS which generate a very large amount of data - a system usually encompass millions of data information, and one query usually runs for tens of thousands of time frames. For this purpose, we designed and developed a new application, DCMS (A data Analytics and Management System for molecular Simulation), that intends to speed up the process …

Embedded System Design For Real-Time Monitoring Of Solitary Embedded System Design For Real-Time Monitoring Of Solitary, Robert Philip O'Brien

USF Tampa Graduate Theses and Dissertations

Alzheimer's disease and other forms of dementia cause cognitive disabilities in the afflicted person. As a result, the person with dementia often requires assistance from a primary caregiver. However, while the caregiver is away from the home they are unaware of the person's status and may not be able to find out without returning to the home due to dementia's effects on cognition.

In this thesis work, a system of embedded devices is presented which tracks a solitary dementia patient in the home in real-time. The system is composed of three main hardware components. Multiple passive and active sensors are …

Investigating Correlation Between Availability Of Free Time Facilities For Pupils And Their Educational Achievements While Exploiting Linked Data And Volunteered Geographic Information, Peter Kovar

Dissertations

The advent of Semantic Web as an extension of the current World Wide Web (Web) brings methods and technologies to structure the data, interlink it with other related data and capture its semantics. This holds for new data to be published as well as for the data already on the Web. The interlinking of data led to definition of a linked data paradigm and the Semantic Web allows for creating a Global Linked Data Space. The linked data sets can combine data coming from heterogeneous sources. Using ontologies the meaning in data from different areas of interest can be compared …

Exploring The Impact That Organisational Culture And Structures Have On Knowledge Management Initiatives, Gavin Digan

Dissertations

The project builds on research in the domain of knowledge management, with a literature review covering several aspects of the domain. There is particular emphasis on knowledge management implementations within organisations. Several researchers in the area offer methodologies or strategies for organisations to adopt, when implementing knowledge management initiatives. These options are covered at length in the literature review along with real world case studies on organisations that have implemented knowledge initiatives with varying degrees of success. A key aspect of the research is assessing the impact of organisational culture on knowledge management initiatives. The literature review contains an extensive …

The Effect Of Stress-­ Relaxation Cycles On The Capacitance Of Dielectric Electro Active Polymers, Cody Rieger, Boon-Chai Ng

Posters, Presentations, and Papers

Dielectric Electro Active Polymers (DEAP) has the potential of converting mechanical energy into useful electrical energy. This material consists of a silicone dielectric film material with a special corrugated surface and a very thin layer of metallic electrodes on both sides of the surface. As these materials allow large mechanical deformations with low operating forces, potential applications include using this material to convert the energy from the ocean waves, and wind. This work examined the capacitance to provide useful information in optimizing the electrical properties for specific applications, and to investigate how the electrical properties are affected by electrical and/or …

Can Passive Mobile Application Traffic Be Identified Using Machine Learning Techniques, Peter Holland

Dissertations

Mobile phone applications (apps) can generate background traffic when the end-user is not actively using the app. If this background traffic could be accurately identified, network operators could de-prioritise this traffic and free up network bandwidth for priority network traffic. The background app traffic should have IP packet features that could be utilised by a machine learning algorithm to identify app-generated (passive) traffic as opposed to user-generated (active) traffic. Previous research in the area of IP traffic classification focused on classifying high level network traffic types originating on a PC device. This research was concerned with classifying low level app …

Can Wikipedia Article Traffic Statistics Be Used To Verify A Technical Indicator? An Exploration Into The Correlation Between Wikipedia Article Traffic Statistics And The Coppock Technical Indicator., Cormac O'Connor

Dissertations

Recent studies have shown that, through the quantification of Wikipedia Usage Patterns as a result of information gathering, stock market moves can be predicted (Moat et al 2013). There was also research performed to determine the predictive nature of Wikipedia Data to predict movie box office success (Mestyan et al. 2013). The goal of any investor, in order to maximize the return of their investments, is to have an edge over other participants in the markets. Several tools and techniques have been used over the years to fulfil this, some proving to generate a consistent stream of income (Gillen 2012). …

An Open Source Implementation And Evaluation Of A Federated Searching Service Based On File Based Index And Relational Database Index, Alan Liu

Dissertations

One of the greatest challenges in the modern information world is the storage of data and the ability to extract usable knowledge from it, to enable enterprises to gain insight that can be leverage to succeed in the competitive environment. Data is constantly being generated and collected at a rapid pace from users and customers via many sources such as intranet, internet and other smart devices. To effectively use the collected data, knowledge must be extracted from it to allow effective and efficient business planning. While the core challenge of data analytics is to extract hidden non-trivial information form large …

Low Power Real-Time Video And Audio Embedded System Design For Naturalistic Bicycle Study, Janardhan Bhima Reddy Karri

USF Tampa Graduate Theses and Dissertations

According to NHTSA Traffic Safety Facts [9], bicyclist deaths and injuries in 2013 are recorded as 732 and 48,000, respectively. In the State of Florida the safety of bicyclists is of particular concern as the bicycle fatality rates are nearly triple the national average. Further Florida ranks #1 on bicycle fatality rate in the nation for several years. To determine the cause of near-misses and crashes, a detailed study of bicyclist behavior and environmental conditions is needed. In a Florida Department of Transport (FDOT) funded project, USF CUTR has proposed naturalistic bicycle study based on ride data collected from 100 …