Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Physical Sciences and Mathematics (980)
- Engineering (695)
- Social and Behavioral Sciences (318)
- Computer Sciences (293)
- Chemistry (267)
-
- Life Sciences (258)
- Education (256)
- Arts and Humanities (193)
- Psychology (169)
- Electrical and Computer Engineering (166)
- Aerospace Engineering (141)
- Environmental Sciences (132)
- Mechanical Engineering (115)
- Medicine and Health Sciences (113)
- Computer Engineering (107)
- Earth Sciences (107)
- Artificial Intelligence and Robotics (96)
- Biomedical Engineering and Bioengineering (85)
- Biology (82)
- Civil and Environmental Engineering (80)
- Oceanography and Atmospheric Sciences and Meteorology (75)
- Mathematics (73)
- Philosophy (73)
- Ecology and Evolutionary Biology (67)
- Polymer Chemistry (63)
- Statistics and Probability (63)
- Materials Science and Engineering (53)
- Geology (52)
- Graphics and Human Computer Interfaces (50)
- Applied Mathematics (49)
- Institution
- Keyword
-
- Machine Learning (48)
- Education (38)
- College of Performing and Visual Arts (36)
- Machine learning (36)
- Theatre Arts and Dance (30)
-
- Theatre Arts and Dance Student Work (30)
- Mathematics (28)
- Simulation (28)
- Optimization (24)
- Deep Learning (20)
- Computer Vision (19)
- Virginia (19)
- Chemistry (15)
- Dance (15)
- Modeling (15)
- Neural Networks (15)
- Artificial Intelligence (14)
- Climate change (14)
- Electrical engineering (14)
- Control (13)
- Ecology (13)
- College of Natural and Health Sciences (12)
- Computer engineering (12)
- CubeSat (12)
- GIS (12)
- Spr_stu (12)
- Clustering (11)
- FEA (11)
- Gender (11)
- Learning (11)
- Publication Year
- Publication Type
- File Type
Articles 1621 - 1650 of 3188
Full-Text Articles in Entire DC Network
Effects Of Input Modality On Capturing Notes, Chaya Bijani
Effects Of Input Modality On Capturing Notes, Chaya Bijani
Master's Theses
The features of the smartphone make it an indispensible commodity of Western urban lifestyles. However, the most common problems of using a mobile device for work-related activities are limited screen space and poor input techniques. People in the workforce whose daily job entails being in a mobile environment generally prefer to carry light, mobile devices along with a pen and a notepad. The purpose of this study was to investigate optimal input modality for taking notes. The three modes of input evaluated were spoken notes, typing on the phone, and writing by hand using a pen and paper. The variables …
Seasonal Road Layout Design In Mountainous Terrain Using Gis With The Side Hill And Least Cost Path Methods, Emil Harold Brundage
Seasonal Road Layout Design In Mountainous Terrain Using Gis With The Side Hill And Least Cost Path Methods, Emil Harold Brundage
Master's Theses
Seasonal road design in mountainous terrain consists of four main phases: route selection, field investigation, surveying, and analysis. The first phase, route selection, consists of two parts: selecting control points at strategic locations, and then determining potential routes between those points. Two geographic information system (GIS) geoprocessing automations were developed to aid a road planner in determining routes between control points. Both automations utilized Environmental Systems Research Institute’s (ESRI) ArcGIS software package. The first method developed was the least cost path method, which makes use of ArcGIS’s cost path tool to find a route between points following a gradual slope. …
Pace, Academic Progress, And The Antecedents Of Student Motivation, Aaron Randall Hiatt
Pace, Academic Progress, And The Antecedents Of Student Motivation, Aaron Randall Hiatt
Master's Theses
The research examined the impact of the pace requirement of the 2010 program integrity legislation at a single graduate institution to gauge its potential for fulfilling the legislation’s stated purpose of increased likelihood of student success. The study determined that there have been changes in registration behavior (particularly in course drop behavior that reduces the number of credits calculated as attempted each semester) since the case institution introduced the pace requirement in Fall 2011. An increase in course completion efficiency was also found. The doctoral candidacy qualifying phase was singled out for a more refined examination, which was loosely tracked …
The Effects Of Robot-Child Interactions On Interpersonal And Intrapersonal Coordination, Kinga Palatinus
The Effects Of Robot-Child Interactions On Interpersonal And Intrapersonal Coordination, Kinga Palatinus
Master's Theses
Coordination is crucial throughout development, from motor development and language acquisition to children’s play and other social interactions. Based on the links between motor and social behavior, proper coordination should help children connect socially with others. Being part of a larger study investigating the effects of a multisystem intervention tool for children with ASD, this work examined the effect of robot-child interaction on interpersonal and intrapersonal coordination in typically developing children. 5-year-olds and 7 year-olds participated in a four-week training protocol, where children had to copy the movements of a small humanoid robot. Measures of cross recurrence quantification analysis revealed …
Impact Of Role Model Gender And Communality On College Women’S Math Performance And Interest In Stem, Elizabeth K. Lawner
Impact Of Role Model Gender And Communality On College Women’S Math Performance And Interest In Stem, Elizabeth K. Lawner
Master's Theses
The current project examined the effect of science, technology, engineering, and math (STEM) role model gender and communality and communal goal endorsement on college women’s math performance and their interest in, perceived belonging in, and perceived communal goal affordance of STEM. The first study was conducted online and did not include math performance, while the second study was conducted in the laboratory and added a math assessment. It was hypothesized that exposure to a female role model would result in greater math performance and interest and perceiving belonging in STEM, exposure to a communal role model would result in increased …
Dynamical X-Ray Diffraction From Arbitrary Semiconductor Heterostructures Containing Dislocations, Paul Rago
Dynamical X-Ray Diffraction From Arbitrary Semiconductor Heterostructures Containing Dislocations, Paul Rago
Master's Theses
High-resolution x-ray diffraction is a valuable non-destructive tool for the structural characterization of semiconductor heterostructures, and measured diffraction profiles contain information on the depth profiles of strain, composition, and defect densities in device structures. Much of this information goes untapped because the lack of phase information prevents direct inversion of the diffraction profile. A common practice is to use dynamical simulations in conjunction with a curve-fitting procedure to extract the profiles of strain and composition in the depth of the material. Prior to this work, the dynamical simulations have been based on perfect, dislocation-free laminar crystals, and this renders the …
Migration, Global Middle Class, And Professional Development: How Chinese Graduate Students In The U.S. Re-Establish A Sense Of Selfhood, Sylvia Shi Pu
Master's Theses
Transnational migration inevitably leads to destabilization of identity. Groups with different characteristics adopt varied strategies to restabilize a sense of selfhood. Elite global migrants, well-equipped with economic, cultural, and educational capital, tend to embrace a cosmopolitan lifestyle in the new location (Favell 2008). In contrast, migrant workers with limited human capital depend on their national peers for useful information and resources in order to make smooth transition across borders (Brown 2011). However, the case of the elite Chinese student migrants fits into neither of the trajectories. In regaining a sense of personhood, those global middle-class migrants end up in a …
Relative Expression Of Germination Genes Sleb, Gerac, And Gpr In Heat Treated Bacillus Licheniformis And Bacillus Subtilis, Valerie Paige Arechiga
Relative Expression Of Germination Genes Sleb, Gerac, And Gpr In Heat Treated Bacillus Licheniformis And Bacillus Subtilis, Valerie Paige Arechiga
Master's Theses
Endospore-forming bacteria of the genus Bacillus are of significant importance to the food industry. Species from this genus exhibit the ability to form metabolically dormant endospores characterized by resistance to heat, UV, and chemical treatment. Spores have undetectable metabolic activity and remain impervious to the harsh conditions of their environment, but they can detect environmental cues signaling favorable growth conditions and begin the process of germination. Once germination and outgrowth are complete, the fully viable cell is capable of reproducing and forming colonies. The resistance of these endospores has been a topic of decades of research, particularly because of their …
Development Of A Digital Controller For Motor Control Experiments In The Ee472 Lab, Jeffrey David D'Amelio
Development Of A Digital Controller For Motor Control Experiments In The Ee472 Lab, Jeffrey David D'Amelio
Master's Theses
A digital motor controller for student lab use is designed, built, and tested. The controller uses an encoder for position measurement, and an H-bridge to drive the electromechanical plant.
A user interface is created to enhance usability of the device. The user interface is able to display key parameters of the control algorithm as well as the state of the system. It is also used to modify the gains and sample rate of the control algorithm.
The design of the system is refined, and 10 units are built for the EE472 Digital Controls Lab. The lab manuals for the first …
Using Spectral Analysis To Evaluate Flute Tone Quality, Ron Yorita
Using Spectral Analysis To Evaluate Flute Tone Quality, Ron Yorita
Master's Theses
Many skilled flutists place a high priority on "good" tone quality, or timbre. Timbre can be defined as the audible difference in character that a listener perceives for two notes played at the same pitch. Different timbres are determined by the combination and balance of harmonics that comprise a note. Unlike pitch and rhythm, timbre is difficult to objectively quantify. This project explores (1) how tone quality is described by skilled flutists, (2) whether the harmonic spectrum has some correlation with tone quality, (3) whether certain harmonic spectra are preferred, or considered "good".
Thirty-one flutists ranging from high school students …
The Effect Of Artery Bifurcation Angles On Fluid Flow And Wall Shear Stress In The Middle Cerebral Artery, Zachary Ramey Jones
The Effect Of Artery Bifurcation Angles On Fluid Flow And Wall Shear Stress In The Middle Cerebral Artery, Zachary Ramey Jones
Master's Theses
Saccular aneurysms are the abnormal plastic deformation of veins and arteries that can lead to lethal thrombus genesis or internal hemorrhaging. Medication and surgery greatly reduce the mortality rates, but treatment is limited by predicting who will develop aneurysms. A common location for saccular aneurysm genesis is at the main middle cerebral artery (MCA) bifurcation. The main MCA bifurcation is comprised of the M1 MCA segment, parent artery, and two M2 segments, daughter arteries. Studies have found that the lateral angle (LA) ratio of the MCA bifurcation is correlated with aneurysm formation. The LA ratio is defined as the angle …
A Novel Dual Modeling Method For Characterizing Human Nerve Fiber Activation, Frank Daniel Sugden
A Novel Dual Modeling Method For Characterizing Human Nerve Fiber Activation, Frank Daniel Sugden
Master's Theses
Presented in this work is the investigation and successful illustration of a coupled model of the human nerve fiber. SPICE netlist code was utilized to describe the electrical properties of the human nervous membrane in tandem with COMSOL Multiphysics, a finite element analysis software tool. The initial research concentrated on the utilization of the Hodgkin-Huxley electrical circuit representation of the nerve fiber membrane. Further development of the project identified the need for a linear circuit model that more closely resembled the McNeal linearization model augmented by the work of Szlavik which better facilitated the coupling of both SPICE and COMSOL …
Analysis And Optimization Of The Scheffler Solar Concentrator, Simone Alberti
Analysis And Optimization Of The Scheffler Solar Concentrator, Simone Alberti
Master's Theses
The Scheffler reflector is a new solar concentrator design which maintains a fixed focus while only having a single axis tracking mechanism. This design makes the construction and operation of high temperature solar concentrators accessible to developing nations. In this project, I wrote computer simulation codes to better understand the dynamics and the effect of deformation or deviations from ideal conditions in order to define necessary manufacturing and operational tolerances. These tools and knowledge drove the prototyping of new reflector concepts by myself and other students on my team. A fiberglass prototype was able to drive the cost of a …
Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson
Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson
Master's Theses
Packed-bed digesters are an alternative to covered lagoon digesters for methane production and anaerobic treatment of dilute wastewaters such as dairy barn flush water. The physical media of packed-beds retain biofilms, often allowing increased treatment rates. Previous studies have evaluated several types of media for digestion of dilute wastewaters, but cost and media fouling have setback commercial development. A major operational cost has been effluent recirculation pumping.
In the present effort, a novel approach to anaerobic digestion of flush dairy water was developed at pilot-scale: broken walnut shells were used as a low-cost packed-bed medium and effluent recirculation was replaced …
A Pareto-Frontier Analysis Of Performance Trends For Small Regional Coverage Leo Constellation Systems, Christopher Alan Hinds
A Pareto-Frontier Analysis Of Performance Trends For Small Regional Coverage Leo Constellation Systems, Christopher Alan Hinds
Master's Theses
As satellites become smaller, cheaper, and quicker to manufacture, constellation systems will be an increasingly attractive means of meeting mission objectives. Optimizing satellite constellation geometries is therefore a topic of considerable interest. As constellation systems become more achievable, providing coverage to specific regions of the Earth will become more common place. Small countries or companies that are currently unable to afford large and expensive constellation systems will now, or in the near future, be able to afford their own constellation systems to meet their individual requirements for small coverage regions.
The focus of this thesis was to optimize constellation geometries …
The Relationship Between Bicycles And Traffic Safety For All Road Users, Jasmine A. Martin
The Relationship Between Bicycles And Traffic Safety For All Road Users, Jasmine A. Martin
Master's Theses
Over the past twenty years bicycle use as a mode of transportation has grown considerably in the United States. Other studies have examined the individual bicyclist’s risk in proportion to the growth in cycling across cities, a phenomenon referred to as ‘safety in numbers.’ This study expands from that research and examines the effect of cyclists on road safety for all road users.
The study examines the roles of bicycle modal split, a city wide analysis, and bicycle infrastructure, a site based analysis, in road safety outcomes. For the city based analysis, twenty years of crash data in 12 California …
Well Clear: General Aviation And Commercial Pilots' Perception Of Unmanned Aerial Vehicles In The National Airspace System, Joseph Taylor Ott
Well Clear: General Aviation And Commercial Pilots' Perception Of Unmanned Aerial Vehicles In The National Airspace System, Joseph Taylor Ott
Master's Theses
The purpose of this research was to determine how different pilot types perceived the subjective concept of the Well Clear Boundary (WCB) and to observe if that boundary changed when dealing with manned versus unmanned aircraft systems (UAS) as well as the effects of other variables. Pilots' perceptions of the WCB were collected objectively through simulator recordings and subjectively through questionnaires. Together, these metrics provided quantitative and qualitative data about pilot WCB perception. The objective results of this study showed significant differences in WCB perception between two different pilot types, as well as WCB significant differences when comparing two different …
An Unsaturated Zone Flux Study In A Highly-Fractured Bedrock Area: Ground Water Recharge Processes At The Masser Recharge Site, East-Central Pennsylvania, Zhengzheng Qin
Master's Theses
This study tested the applicability of the Episodic Master Recession method and utilized the source-responsive flow theory to quantify ground water recharge and simulate preferential flow in the vadose zone at the Masser Recharge Site in east-central Pennsylvania. The ground water recharge shows strong seasonal variations. The shallow fractures form preferential flow paths and predominate in the vadose zone recharge processes, as reflected in the ground water-table elevation rise. They also influence the ground water-table recession rate, reflected in the rapid water-table recession in the deeper well with a high hydraulic conductivity fractured zone. Most importantly, the source-responsive flow model …
Stereotype Threat, Self-Affirmation, And Women's Statistics Performance, Blanca Tapia
Stereotype Threat, Self-Affirmation, And Women's Statistics Performance, Blanca Tapia
Master's Theses
Stereotype threat (fear of confirming a negative group stereotype that in turn can inhibit academic performance) has been implicated in the gender gap observed in the field of mathematics. Even though stereotype threat depresses women's performance, there has been much research reporting various interventions that ameliorate its negative effects. The current study investigated stereotype threat specifically in statistics--an unexplored area in the research literature --and the alleviating effects of self-affirmation. Participants in three conditions (control, stereotype threat, stereotype threat + affirmation) completed a statistics test. In both stereotype threat conditions participants were given a verbal prime to induce stereotype threat, …
A Theoretical Calculation Of The Polarization Of Scattered Light And A Comparison With Aeronet Measurements: Possible Applications To Aerosol Discrimination, Patricio German Piedra
A Theoretical Calculation Of The Polarization Of Scattered Light And A Comparison With Aeronet Measurements: Possible Applications To Aerosol Discrimination, Patricio German Piedra
Master's Theses
Despite considerable efforts by many atmospheric scientists, the identification and classification of aerosols remain a big challenge. On the atmospheric scale, large surveys of aerosols rely heavily on light scattering. The degree of linear polarization (DLP) is sensitive to the size and index of refraction of the aerosol particles and may provide an accurate method for discriminating aerosol types. In this thesis, Mie scattering was implemented to yield both the parallel and perpendicular components of the scattered electric field. In a first set of results, the calculated DLP was used to reproduce measurements of DLP along a principal plane for …
The Application Of P-Bar Theory In Transformation-Based Error-Driven Learning, Bryant Harold Walley
The Application Of P-Bar Theory In Transformation-Based Error-Driven Learning, Bryant Harold Walley
Master's Theses
In P-bar Theory, Perkins et al. (2014) proposed a rule based method for determining the context of a partext (i.e., a part of a text document).
In Transformation-Based Error-Driven Learning and Natural Language Processing: A Case Study in Part-of-Speech Tagging Brill (1995) demonstrates a method of error-driven learning applied to individual words at the sentence level to determine the part of speech each word represents.
We combine these two concepts providing a transformation-based error-driven learning algorithm to improve the results obtained from the static rules Perkins proposed and determine if the rule order prediction will provide additional metadata.
Approximation Of The Scattering Amplitude Using Nonsymmetric Saddle Point Matrices, Amber Sumner Robertson
Approximation Of The Scattering Amplitude Using Nonsymmetric Saddle Point Matrices, Amber Sumner Robertson
Master's Theses
In this thesis we look at iterative methods for solving the primal (Ax = b) and dual (AT y = g) systems of linear equations to approximate the scattering amplitude defined by gTx =yTb. We use a conjugate gradient-like iteration for a unsymmetric saddle point matrix that is contructed so as to have a real positive spectrum. We find that this method is more consistent than known methods for computing the scattering amplitude such as GLSQR or QMR. Then, we use techniques from "matrices, moments, and quadrature" to compute the scattering amplitude …
A Vegetation Analysis On Horn Island, Mississippi, Ca. 1940 Using Characteristic Dimensions Derived From Historical Aerial Photography, Guy Wilburn Jeter Jr.
A Vegetation Analysis On Horn Island, Mississippi, Ca. 1940 Using Characteristic Dimensions Derived From Historical Aerial Photography, Guy Wilburn Jeter Jr.
Master's Theses
Horn Island is part of the MS/AL barrier island chain in the northern Gulf of Mexico located approximately 18kn off the coast of Mississippi. This island’s habitats have undergone many transitions over the last several decades. The goal of this study was to quantify habitat change over a seventy year period using historical black and white photography from 1940. Using present NAIP imagery from the USDA, habitat structure was estimated by using geo-statistics, and second order statistics, from a co-occurrence matrix, to characterize texture for habitat classification. Percent land cover was then calculated to determine overall land cover change over …
A Novel Method For Confirming The Presence Of Volatile Reduced Sulfide Compounds Via Inductively Coupled Plasma-Optical Emission Spectroscopy, Krystal Lynne Parker
A Novel Method For Confirming The Presence Of Volatile Reduced Sulfide Compounds Via Inductively Coupled Plasma-Optical Emission Spectroscopy, Krystal Lynne Parker
Master's Theses
Millions of dollars in destruction in the past decade have resulted from the use of Chinese drywall in homes. There are also potential health hazards related to this corrosive material. As such, it is important to find a way to identify Chinese drywall. Drywall can be tested for certain markers, such as strontium, sulfur, and carbonates to identify it as corrosive Chinese drywall. The laboratory preparation and analysis should be efficient and cost effective. The methods previously used, such as an X-ray fluorescence gun have had issues with getting a proper reading due to the layers of other materials found …
The Structure And Properties Of Clique Graphs Of Regular Graphs, Jan Burmeister
The Structure And Properties Of Clique Graphs Of Regular Graphs, Jan Burmeister
Master's Theses
In the following thesis, the structure and properties of G and its clique graph clt (G) are analyzed for graphs G that are non-complete, regular with degree δ , and where every edge of G is contained in a t -clique. In a clique graph clt (G), all cliques of order t of the original graph G become the clique graph’s vertices, and the vertices of the clique graph are adjacent if and only if the corresponding cliques in the original graph have at least 1 vertex in common. This thesis mainly investigates if …
Reinforcement Learning Of Distributed Surveillance Plans, Madhavi Chittireddy
Reinforcement Learning Of Distributed Surveillance Plans, Madhavi Chittireddy
Master's Theses
This thesis describes the design and implementation of a Reinforcement Learning algorithm on a camera surveillance model which is used to know the stackelberg strategies of attacker and defender. This reinforcement learning algorithm is compared with the uniform policy and hill climbing algorithms by executing them on a common set of different data files, generated programmatically with various combinations of problem size, location, and orientation transitions as well as rewards of attacker and defender. The comparison includes the time taken to obtain better stackelberg policy and the resulted final pay-off of the defender. This thesis shows that the reinforcement learning …
A Study Of Shock Analysis Using The Finite Element Method Verified With Euler-Bernoulli Beam Theory; Mechanical Effects Due To Pulse Width Variation Of Shock Inputs; And Evaluation Of Shock Response Of A Mixed Flow Fan, David Jonathan Gonzalez Campos
A Study Of Shock Analysis Using The Finite Element Method Verified With Euler-Bernoulli Beam Theory; Mechanical Effects Due To Pulse Width Variation Of Shock Inputs; And Evaluation Of Shock Response Of A Mixed Flow Fan, David Jonathan Gonzalez Campos
Master's Theses
A Study Of Shock Analysis Using The Finite Element Method Verified With Euler-Bernoulli Beam Theory; Mechanical Effects Due To Pulse Width Variation Of Shock Inputs; And Evaluation Of Shock Response Of A Mixed Flow Fan
David Jonathan González Campos
For many engineers that use finite element analysis or FEA, it is very important to know how to properly model and obtain accurate solutions for complicated loading conditions such as shock loading. Transient acceleration loads, such as shocks, are not as common as static loads. Analyzing these types of problems is less understood, which is the basis for this study. FEA …
Dcamp: Distributed Common Api For Measuring Performance, Alexander Paul Sideropoulos
Dcamp: Distributed Common Api For Measuring Performance, Alexander Paul Sideropoulos
Master's Theses
Although the nearing end of Moore’s Law has been predicted numerous times in the past, it will eventually come to pass. In forethought of this, many modern computing systems have become increasingly complex, distributed, and parallel. As software is developed on and for these complex systems, a common API is necessary for gathering vital performance related metrics while remaining transparent to the user, both in terms of system impact and ease of use.
Several distributed performance monitoring and testing systems have been proposed and implemented by both research and commercial institutions. However, most of these systems do not meet several …
Control Of A Spacecraft Using Mixed Momentum Exchange Devices, Blake J. Currie
Control Of A Spacecraft Using Mixed Momentum Exchange Devices, Blake J. Currie
Master's Theses
Hardware configurations, a control law, and a steering law are developed for a mixed hardware spacecraft that uses both control moment gyros and reaction wheels. Replacing one or more gyros in a spacecraft with a reaction wheel has potential for cost savings while still achieving much greater performance than using reaction wheels alone. Several simulated tests are run to compare the performance to a traditional all reaction wheel or all control moment gyro spacecraft, including analysis of failure modes and singular configurations. The mixed system performed similarly to all gyro systems, responding within 6% of the gyro system’s time for …
Adapting Monte Carlo Localization To Utilize Floor And Wall Texture Data, Stephanie Krapil
Adapting Monte Carlo Localization To Utilize Floor And Wall Texture Data, Stephanie Krapil
Master's Theses
Monte Carlo Localization (MCL) is an algorithm that allows a robot to determine its location when provided a map of its surroundings. Particles, consisting of a location and an orientation, represent possible positions where the robot could be on the map. The probability of the robot being at each particle is calculated based on sensor input.
Traditionally, MCL only utilizes the position of objects for localization. This thesis explores using wall and floor surface textures to help the algorithm determine locations more accurately. Wall textures are captured by using a laser range finder to detect patterns in the surface. Floor …