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Articles 1201 - 1230 of 2105
Full-Text Articles in Computer Sciences
Band Gap Engineering Via Doping: A Predictive Approach, Antonis N. Andriotis, Madhu Menon
Band Gap Engineering Via Doping: A Predictive Approach, Antonis N. Andriotis, Madhu Menon
Center for Computational Sciences Faculty Publications
We employ an extension of Harrison's theory at the tight binding level of approximation to develop a predictive approach for band gap engineering involving isovalent doping of wide band gap semiconductors. Our results indicate that reasonably accurate predictions can be achieved at qualitative as well as quantitative levels. The predictive results were checked against ab initio ones obtained at the level of DFT/SGGA + U approximation. The minor disagreements between predicted and ab initio results can be attributed to the electronic processes not incorporated in Harrison's theory. These include processes such as the conduction band anticrossing [Shan et al., …
An Enhanced Mapreduce Workload Allocation Tool For Spot Market Resources, John Stephen Hudzina
An Enhanced Mapreduce Workload Allocation Tool For Spot Market Resources, John Stephen Hudzina
CCAC Theses and Dissertations
When a cloud user allocates a cluster to execute a map-reduce workload, the user must determine the number and type of virtual machine instances to minimize the workload's financial cost. The cloud user may rent on-demand instances at a fixed price or spot instances at a variable price to execute the workload. Although the cloud user may bid on spot virtual machine instances at a reduced rate, the spot market auction may delay the workload's start or terminate the spot instances before the workload completes. The cloud user requires a forecast for the workload's financial cost and completion time to …
Fall: A Fair And Low Latency Queuing Scheme For Data Center Networks, Lin Xue, Chui Hui Chiu, Suman Kumar, Praveenkumar Kondikoppa, Seung Jong Park
Fall: A Fair And Low Latency Queuing Scheme For Data Center Networks, Lin Xue, Chui Hui Chiu, Suman Kumar, Praveenkumar Kondikoppa, Seung Jong Park
Computer Science Faculty Research & Creative Works
Low latency, high throughput, and fairness are the stringent performance requirements of data center networks. For web applications continue to thrive, data center must remain effective by addressing these challenges. While most of the challenges have been handled by data center specific transport protocols (e.g. DCTCP), these transport protocols are not default options for data center users. Free choice of transport protocols demands careful consideration for an effective solution. We argue that queuing scheme at layer-2 switches hold the key to address these issues. Therefore, in this paper, we present FaLL, a queuing scheme for data center networks that meets …
The Unified Behavior Framework For The Simulation Of Autonomous Agents, Daniel M. Roberson
The Unified Behavior Framework For The Simulation Of Autonomous Agents, Daniel M. Roberson
Theses and Dissertations
Since the 1980s, researchers have designed a variety of robot control architectures intending to imbue robots with some degree of autonomy. A recently developed architecture, the UBF, implements a variation of the three-layer architecture with a reactive controller to rapidly make behavior decisions. Additionally, the UBF utilizes software design patterns that promote the reuse of code and free designers to dynamically switch between behavior paradigms. This paper explores the application of the UBF to the simulation domain. By employing software engineering principles to implement the UBF architecture within an open-source simulation framework, we have extended the versatility of both. The …
Constructing Cost-Effective And Targetable Ics Honeypots Suited For Production Networks, Michael M. Winn
Constructing Cost-Effective And Targetable Ics Honeypots Suited For Production Networks, Michael M. Winn
Theses and Dissertations
Honeypots are a technique that can mitigate the risk of cyber threats. Effective honeypots are authentic and targetable, and their design and implementation must accommodate risk tolerance and financial constraints. The proprietary, and often expensive, hardware and software used by Industrial Control System (ICS) devices creates the challenging problem of building a flexible, economical, and scalable honeypot. This research extends Honeyd into Honeyd+, making it possible to use the proxy feature to create multiple high interaction honeypots with a single Programmable Logic Controller (PLC). Honeyd+ is tested with a network of 75 decoy PLCs, and the interactions with the decoys …
Tactical Ai In Real Time Strategy Games, Donald A. Gruber
Tactical Ai In Real Time Strategy Games, Donald A. Gruber
Theses and Dissertations
The real time strategy (RTS) tactical decision making problem is a difficult problem. It is generally more complex due to its high degree of time sensitivity. This research effort presents a novel approach to this problem within an educational, teaching objective. Particular decision focus is target selection for a artificial intelligence (AI) RTS game model. The use of multi-objective evolutionary algorithms (MOEAs) in this tactical decision making problem allows an AI agent to make fast, effective solutions that do not require modification to the current environment. This approach allows for the creation of a generic solution building tool that is …
Context-Sensitive Entity Resolution, William C. Decker
Context-Sensitive Entity Resolution, William C. Decker
Theses and Dissertations
This dissertation proposes an entity resolution approach that is context-sensitive, meaning it relies less on high-risk information, such as social security numbers, to discern whether records from a data set belong to the same real-world individual or to different real-world individuals. The research follows an iterative process of assessing the quality, or fitness of use, of identity data housed in an educational institution and then processing the data with the proposed context-sensitive entity resolution (ER) rule set. The efficacy of this process is demonstrated through calculation of the four-year adjusted cohort graduation rate, a prevalent longitudinal data analysis challenge for …
The Tail Wagging The Dog: An Overdue Examination Of Student Teaching Evaluations, Patti Miles, Deanna House
The Tail Wagging The Dog: An Overdue Examination Of Student Teaching Evaluations, Patti Miles, Deanna House
Information Systems and Quantitative Analysis Faculty Publications
Purpose: The purpose of this research is to examine the impact of several factors beyond the professor’s control and their unique impact on Student Teaching Evaluations (STEs). The present research pulls together a substantial amount of data to statistically analyze several academic historical legends about just how vulnerable STEs are to the effects of: class size, course type, professor gender, and course grades.
Design/methodology/approach: This research is utilizes over 30,000 individual student evaluations of 255 professors, spanning six semesters, during a three year time period to test six hypotheses. The final sample represents 1057 classes ranging in size between 10 …
Unified Behavior Framework For Discrete Event Simulation Systems, Alexander J. Kamrud
Unified Behavior Framework For Discrete Event Simulation Systems, Alexander J. Kamrud
Theses and Dissertations
Intelligent agents provide simulations a means to add lifelike behavior in place of manned entities. Generally when developed, a single intelligent agent model is chosen, such as rule based, behavior trees, etc. This choice introduces restrictions into what behaviors agents can manifest, and can require significant testing in edge cases. This thesis presents the use of the UBF in the AFSIM environment. The UBF provides the flexibility to implement any and all intelligent agent models, allowing the developer to choose the model he/she feels best fits the experiment at hand. Furthermore, the UBF demonstrates several key software engineering principles through …
Evaluating Machine Learning Classifiers For Hybrid Network Intrusion Detection Systems, Michael D. Rich
Evaluating Machine Learning Classifiers For Hybrid Network Intrusion Detection Systems, Michael D. Rich
Theses and Dissertations
Existing classifier evaluation methods do not fully capture the intended use of classifiers in hybrid intrusion detection systems (IDS), systems that employ machine learning alongside a signature-based IDS. This research challenges traditional classifier evaluation methods in favor of a value-focused evaluation method that incorporates evaluator-specific weights for classifier and prediction threshold selection. By allowing the evaluator to weight known and unknown threat detection by alert classification, classifier selection is optimized to evaluator values for this application. The proposed evaluation methods are applied to a Cyber Defense Exercise (CDX) dataset. Network data is processed to produce connection-level features, then labeled using …
Git As An Encrypted Distributed Version Control System, Russell G. Shirey
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 …
Focal Structures Analysis In Complex And Social Networks, Fatih Sen
Focal Structures Analysis In Complex And Social Networks, Fatih Sen
Theses and Dissertations
Identifying influential individuals is a well-known approach in extracting actionable knowledge in a network. Previous researches suggest measures to identify influential individuals, e.g., they focus on the question ``which individuals are best connected to others or have the most influence?". Such individuals, however, might not represent the context (relationships, interactions, etc.) entirely in a social network. For example, it is nearly an impossible task for a single individual to organize a mass protest of the scale of the 2011 Arab Spring and the 2012 Occupy Wall Street. Similarly, other events such as mobilizing the 2013 Taksim square-Gezi Park protesters, coordinating …
Multilingual Extraction Ontologies, David W. Embley, Stephen W. Liddle, Deryle W. Lonsdale, Yuri Tijerino
Multilingual Extraction Ontologies, David W. Embley, Stephen W. Liddle, Deryle W. Lonsdale, Yuri Tijerino
Journal of Undergraduate Research
On December 29, 2009 we were informed that our application for a 2010 MEG grant was approved. This final report sketches the accomplishments attained during the project’s timeframe since then.
Modeling And Simulation Of Evacuation Plan For Hancock Stadium, Nirmal Neranjan Weerasekara
Modeling And Simulation Of Evacuation Plan For Hancock Stadium, Nirmal Neranjan Weerasekara
Theses and Dissertations
The goal of this study is to use Modeling and Simulation of Evacuation Plan (MSEP) to support management to execute proper evacuation plan in case of emergency at Hancock Stadium in Illinois State University. Analyses of the research literature and evacuation scenarios are used to build a simulation system that will connect a description of emergency and evacuation situation with its context. It shows how an evacuation plan actually functions. The results of the study will help safety managers to understand the current situations of evacuation according to the specific simulation scenarios. The evacuation simulation is categorized according to the …
A Kansa-Radial Basis Function Method For Elliptic Boundary Value Problems In Annular Domains, Xiao Yan Liu, Andreas Karageorghis, C. S. Chen
A Kansa-Radial Basis Function Method For Elliptic Boundary Value Problems In Annular Domains, Xiao Yan Liu, Andreas Karageorghis, C. S. Chen
Faculty Publications
We employ a Kansa-radial basis function (RBF) method for the numerical solution of elliptic boundary value problems in annular domains. This discretization leads, with an appropriate selection of collocation points and for any choice of RBF, to linear systems in which the matrices possess block circulant structures. These linear systems can be solved efficiently using matrix decomposition algorithms and fast Fourier transforms. A suitable value for the shape parameter in the various RBFs used is found using the leave-one-out cross validation algorithm. In particular, we consider problems governed by the Poisson equation, the inhomogeneous biharmonic equation and the inhomogeneous Cauchy–Navier …
Unknown Threat Detection With Honeypot Ensemble Analsyis Using Big Datasecurity Architecture, Michael Eugene Sanders
Unknown Threat Detection With Honeypot Ensemble Analsyis Using Big Datasecurity Architecture, Michael Eugene Sanders
Theses and Dissertations
The amount of data that is being generated continues to rapidly grow in size and complexity. Frameworks such as Apache Hadoop and Apache Spark are evolving at a rapid rate as organizations are building data driven applications to gain competitive advantages. Data analytics frameworks decomposes our problems to build applications that are more than just inference and can help make predictions as well as prescriptions to problems in real time instead of batch processes.
Information Security is becoming more important to organizations as the Internet and cloud technologies become more integrated with their internal processes. The number of attacks and …
Using Software Defined Networking To Solve Missed Firewall Architecture In Legacy Networks, Jared Dean Vogel
Using Software Defined Networking To Solve Missed Firewall Architecture In Legacy Networks, Jared Dean Vogel
Theses and Dissertations
This study is concerned with migrating traditional networks and their inherent firewall architecture to Software Defined Networking (SDN) architecture to provide an initial attempt at preventing application downtime due to hidden firewall domain rules. In legacy organization environments the networking engineers, firewall teams, and application analysts are often silo groups, but Software Defined Networking (SDN) can blur the lines between these group silos.
This thesis first outlines the interworking of SDN, traditional firewall architecture and how it interacts with SDN, an experiment of implementation, and the resulting conclusions.
Testing with SDN shows we are approaching new environments where the edges …
Isomorphism And Similarity For 2-Generation Pedigrees, Haitao Jiang, Guohui Lin, Weitian Tong, Daming Zhu, Binhai Zhu
Isomorphism And Similarity For 2-Generation Pedigrees, Haitao Jiang, Guohui Lin, Weitian Tong, Daming Zhu, Binhai Zhu
Computer Science: Faculty Publications
We consider the emerging problem of comparing the similarity between (unlabeled) pedigrees. More specifically, we focus on the simplest pedigrees, namely, the 2-generation pedigrees. We show that the isomorphism testing for two 2-generation pedigrees is GI-hard. If the 2-generation pedigrees are monogamous (i.e., each individual at level-1 can mate with exactly one partner) then the isomorphism testing problem can be solved in polynomial time. We then consider the problem by relaxing it into an NP-complete decomposition problem which can be formulated as the Minimum Common Integer Pair Partition (MCIPP) problem, which we show to be FPT by exploiting a property …
Parameters Identification For A Composite Piezoelectric Actuator Dynamics, Mohammad Saadeh, Mohamed Trabia
Parameters Identification For A Composite Piezoelectric Actuator Dynamics, Mohammad Saadeh, Mohamed Trabia
Mechanical Engineering Faculty Research
This work presents an approach for identifying the model of a composite piezoelectric (PZT) bimorph actuator dynamics, with the objective of creating a robust model that can be used under various operating conditions. This actuator exhibits nonlinear behavior that can be described using backlash and hysteresis. A linear dynamic model with a damping matrix that incorporates the Bouc–Wen hysteresis model and the backlash operators is developed. This work proposes identifying the actuator’s model parameters using the hybrid master-slave genetic algorithm neural network (HGANN). In this algorithm, the neural network exploits the ability of the genetic algorithm to search globally to …
Interpreting Multitouch Gestures, Michael Schuweiler
Interpreting Multitouch Gestures, Michael Schuweiler
Scholarly Horizons: University of Minnesota, Morris Undergraduate Journal
Interpreting multitouch interactions can be as simple as understanding code that handles these multitouches and this code's associated actions. As more touch events are added to an input, inputs become more complex. There are multiple approaches to interpreting these inputs between users and touchscreens. Researchers in this field find answers to common problems and provide developers with tools that make interactions with multitouch devices easier to describe and incorporate into their systems. These tools are then used to create gestures through different approaches, specifically through demonstration and by declaration. In this paper, these researchers' tools are described and compared.
Dcms: A Data Analytics And Management System For Molecular Simulation, Meryem Berrada
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 …
Sensitivity Analysis For The Winning Algorithm In Knowledge Discovery And Data Mining ( Kdd ) Cup Competition 2014, Fakhri Ghassan Abbas
Sensitivity Analysis For The Winning Algorithm In Knowledge Discovery And Data Mining ( Kdd ) Cup Competition 2014, Fakhri Ghassan Abbas
Theses and Dissertations
This thesis applies multi-way sensitivity analysis for the winning algorithm in the Knowledge Discovery in Data Mining (KDD) cup competition 2014 -`Predicting Excitement at Donors.org'. Because of the highly advanced nature of this competition, analyzing the winning solution under a variety of different conditions provides insight about each of the models the winning team has used in the competition. The study follows Cross Industry Standard Process (CRISP) for data mining to study the steps taken to prepare, model and evaluate the model. The thesis focuses on a gradient boosting model. After careful examination of the models created by the researchers …
The Impact Of Image Synonyms In Graphical-Based Authentication Systems, Jonathan William Sparks
The Impact Of Image Synonyms In Graphical-Based Authentication Systems, Jonathan William Sparks
CCAC Theses and Dissertations
Traditional text-based passwords used for authentication in information systems have several known issues in the areas of usability and security. Research has shown that when users generate passwords for systems, they tend to create passwords that are subject to compromise more so than those created randomly by the computer. Research has also shown that users have difficulty remembering highly secure, randomly created, text-based passwords.
Graphical-based passwords have been shown to be highly memorable for users when applied to system authentication. However, graphical-based authentication systems require additional cognitive load to recognize and enter a password compared to traditional text-based authentication that …
Intersections Of Critical Systems Thinking And Community Based Participatory Research In Developing A Web Site For Autistic Adults, Dora Madeline Raymaker
Intersections Of Critical Systems Thinking And Community Based Participatory Research In Developing A Web Site For Autistic Adults, Dora Madeline Raymaker
Dissertations and Theses
People with disabilities, including those on the autism spectrum, comprise the world's largest minority and experience significant inequities in Internet use. Existing standards for accessible web sites are necessary but not sufficient without the direct engagement of end users in identifying access needs. Yet little is known about methods for effective engagement, and there are no systematically derived Web accessibility guidelines for autistic end users. Here I explore a hybrid approach to direct engagement using critical systems thinking (CST) and community based participatory research (CBPR) during the co-development of a healthcare-focused web site by the Academic Autism Spectrum Partnership in …
An Interpretive Phenomenological Analysis Inquiry Into Facebook Newcomer Motivations For Participatory Activities, Kristin Raub
An Interpretive Phenomenological Analysis Inquiry Into Facebook Newcomer Motivations For Participatory Activities, Kristin Raub
CCAC Theses and Dissertations
This qualitative study provided insight into the phenomenon of newcomers in social networking, in particular, to understand what role specific Facebook features play in motivating content sharing and contribution among newcomers. Research indicated that the first several months or years of social networking site (SNS) membership are the most crucial in terms of indicating long-term participation and commitment to the SNS. Long-term participation is specifically manifested through interactions with peers who are members of the same website and through interactivity such as content sharing and contribution. A number of quantitative studies have focused on motivations for user contribution in social …
A Hybrid Approach To Indoor Sensor Area Localization And Coverage, Mengmeng Gai
A Hybrid Approach To Indoor Sensor Area Localization And Coverage, Mengmeng Gai
UNO Student Research and Creative Activity Fair
This study presents a hybrid approach to indoor object detection and tracking. The test area is partitioned into regions that are covered by sensors placed on the ceilings. The approximate location of an object is determined by these sensors using RSSI. The region determination is then followed by localizing the exact location of the object using Building Information Modeling (BIM) and the 3D stereo image measurements. To determine the coverage ratio of a region for better placement of sensors, the 3D space is partitioned into 2D planes whose coverage points are determined by a newly developed software product called LOCOPac. …
The Hosoya Entropy Of A Graph, Abbe Mowshowitz, Matthias Dehmer
The Hosoya Entropy Of A Graph, Abbe Mowshowitz, Matthias Dehmer
Publications and Research
This paper demonstrates properties of Hosoya entropy, a quantitative measure of graph complexity based on a decomposition of the vertices linked to partial Hosoya polynomials. Connections between the information content of a graph and Hosoya entropy are established, and the special case of Hosoya entropy of trees is investigated.
Psycholinguistic Study: Deaf Children Vs. Codas And Language Comprehension, Amber Smith, Michael Jones
Psycholinguistic Study: Deaf Children Vs. Codas And Language Comprehension, Amber Smith, Michael Jones
Journal of Undergraduate Research
This project will use an EEG to differentiate brain response to given stimuli between deaf and CODA (children of deaf adults) participants. This project is simple in nature, we will administer two tests: one in ASL and one in English, while the participant is wearing the EEG. We will then analyze and compare the data between the two groups.
Learning Object-Oriented Programming In Python: Towards An Inventory Of Difficulties And Testing Pitfalls, Craig Miller, Amber Settle, John Lalor
Learning Object-Oriented Programming In Python: Towards An Inventory Of Difficulties And Testing Pitfalls, Craig Miller, Amber Settle, John Lalor
Technical Reports
We report a small yet detailed study where we recorded students completing an object-oriented programming exercise in the context of a CS2 course using Python. All students struggled while completing the assignment, most notably experiencing difficulties with parameters and referencing elements with object-dot notation. While previous research has identified these areas as troublesome for novice programmers, our analysis suggests that parameters and reference specifications are particularly critical prerequisites for learning advanced object-oriented concepts with the Python programming language. Given our findings, we recommend extensive practice with parameter passing and object-dot notation before addressing advanced object-oriented concepts in a Python course.