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A Subcontinental Reconstruction Of Invasion Patterns And Processes For The Past Two Centuries, Teresa Lynn Clark Jan 2015

A Subcontinental Reconstruction Of Invasion Patterns And Processes For The Past Two Centuries, Teresa Lynn Clark

Open Access Theses

Understanding large-scale invasion patterns and processes is essential for effective and proactive management of exotic species that have caused significant ecological and economic damages. While many studies have focused on specific habitats and species, my research is aimed at the broad-scale patterns of expansion during the course of the past two centuries. I use long-term herbarium specimens to recreate the spatiotemporal distributions of 29 invasive plant species within the eastern United States. The emerging spatial patterns reveal species’ expansion through a continuum of radial expansion, long distance jump dispersals, and range infilling. This study identifies a set of metrics that …

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Community Detection Using Efficient Modularity Optimization Method: Labelmod With Single And Multi-Layer Graphs, Seokhun Bang Jan 2015

Community Detection Using Efficient Modularity Optimization Method: Labelmod With Single And Multi-Layer Graphs, Seokhun Bang

Open Access Theses

Graph clustering is a field of study that helps reveal characteristics of communities. Systems can be viewed as networks and form communities in various areas such as biology, computer science, engineering, economics, and politics. A clustering algorithm is a tool that detects communities and it can be also considered as a pre-processing step to study the characteristics of detected communities. Many efforts were made to develop a well performing clustering algorithm in different types of networks. In recent literature, a concept of multi-layer graphs emerged, and clustering algorithms are being developed to detect communities in the multi-layer graphs. In this …

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Non Destructive Testing Of Soft Body Armor, Karan Bhise Jan 2015

Non Destructive Testing Of Soft Body Armor, Karan Bhise

Open Access Theses

Pristine bullet proof vests are extremely effective at halting pre-determined projectile threats and have saved over 3000 lives. However, the effectiveness of these vests to halt a bullet is seen to decrease over time.Owing to the importance of bullet proof vests over a period of time, tests to determine their effectiveness have been carried out on every batch of vests at the time of inception and at certain time intervals by shooting a bullet through them. A few vests from every batch are picked up and shot at to check for bullet penetration during this process while these results are …

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A Subcontinental Reconstruction Of Invasion Patterns And Processes For The Past Two Centuries, Teresa Lynn Clark Jan 2015

A Subcontinental Reconstruction Of Invasion Patterns And Processes For The Past Two Centuries, Teresa Lynn Clark

Open Access Theses

Understanding large-scale invasion patterns and processes is essential for effective and proactive management of exotic species that have caused significant ecological and economic damages. While many studies have focused on specific habitats and species, my research is aimed at the broad-scale patterns of expansion during the course of the past two centuries. I use long-term herbarium specimens to recreate the spatiotemporal distributions of 29 invasive plant species within the eastern United States. The emerging spatial patterns reveal species’ expansion through a continuum of radial expansion, long distance jump dispersals, and range infilling. This study identifies a set of metrics that …

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The Home Literacy And Numeracy Environment In Preschool: Cross-Domain Relations Of Parent Practices And Child Outcomes, Amy Rose Napoli Jan 2015

The Home Literacy And Numeracy Environment In Preschool: Cross-Domain Relations Of Parent Practices And Child Outcomes, Amy Rose Napoli

Open Access Theses

There is ample evidence indicating that early literacy and numeracy skills are important to later academic achievement, and that these early skills develop together. There is also evidence that parent-child literacy and numeracy practices are predictive of children’s literacy and numeracy skills within their respective domains. However, there is limited research on the relations between the home literacy environment (HLE) and numeracy outcomes, and the home numeracy environment (HNE) and literacy outcomes. Thus, the purpose of the present study was to investigate the relations of the HLE and HNE to children’s literacy and numeracy practices, both within and across domains. …

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Heat And Mass Transfer Analysis Of A Film Evaporative Mems Tunable Array, William John O'Neill Jan 2015

Heat And Mass Transfer Analysis Of A Film Evaporative Mems Tunable Array, William John O'Neill

Open Access Theses

This thesis details the heat and mass transfer analysis of a MEMs microthruster designed to provide propulsive, attitude control and thermal control capabilities to a cubesat. This thruster is designed to function by retaining water as a propellant and applying resistive heating in order to increase the temperature of the liquid-vapor interface to either increase evaporation or induce boiling to regulate mass flow. The resulting vapor is then expanded out of a diverging nozzle to produce thrust. Because of the low operating pressure and small length scale of this thruster, unique forms of mass transfer analysis such as non-continuum gas …

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Training And Evaluation Of Virtual Sensors For Rooftop Units, Jebaraj Vasudevan Jan 2015

Training And Evaluation Of Virtual Sensors For Rooftop Units, Jebaraj Vasudevan

Open Access Theses

This thesis focuses on assessing and extending specific virtual sensors for rooftop units with

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Friendships And Networks In Chinese Adolescents: Academic Achievement And Academic Engagement, Siyu Xu Jan 2015

Friendships And Networks In Chinese Adolescents: Academic Achievement And Academic Engagement, Siyu Xu

Open Access Theses

This longitudinal study examined the associations between Chinese adolescents’ academic adjustment (i.e., academic achievement and academic engagement) and network affiliates and friends’ academic adjustment. Seven hundred and twenty seventh grade students (Mean age= 13.24, 382 boys and 338 girls) participated in the study. They were followed into the eighth grade (Mean Age = 14.26, 343 boys and 312 girls). Adolescents’ academic achievement was highly correlated with that of their friends and network affiliates at both grades. Adolescents’ academic engagement was not, however, correlated with their friends and network affiliates’ academic engagement. First year friends’ academic achievement significantly predicted second year …

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A Technological Approach To Bloodstain Pattern Analysis, Michael Keith Burgess Jan 2015

A Technological Approach To Bloodstain Pattern Analysis, Michael Keith Burgess

Open Access Theses

The field of Bloodstain Pattern Analysis has had many achievements since the mid 1900’s, such as using computers in a physical crime scene. However, the computer aided programs that are in use today are sometimes bulky, many times expensive, and always require a large amount of training to be used properly. In addition to this problem, many investigators use the same formula of determining the angle of incidence on every type of surface, planar or not, which creates mistakes in their findings. Using a technological approach, this investigation examined a new approach for collecting data from bloodstains. This examination answered …

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A Numerical Tool For Evaluating And Optimizing Multijunction Pv Systems, Kevon Clint Charles Jan 2015

A Numerical Tool For Evaluating And Optimizing Multijunction Pv Systems, Kevon Clint Charles

Open Access Theses

Solar energy is one of the most abundant sources of clean renewable energy and is also an important source of electrical energy. Solar energy has the potential of meeting all of the world's energy needs, and has seen substantial growth and development in recent years. Solar cells can convert sunlight directly into electrical energy, and the solar industry has made a great deal of progress in making them less costly and more efficient. The conversion efficiency of solar cells, however, is one of the main factors that limits the solar industry from competing with fossil fuels. Once the efficiency of …

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Novel Electricity Supply Techniques For Sustainable Ultraviolet Water Purification, Zachary Koch Jan 2015

Novel Electricity Supply Techniques For Sustainable Ultraviolet Water Purification, Zachary Koch

Open Access Theses

Millions of people have gained access to clean and safe drinking water in the last 15 years. However, millions of individuals continue to experience poor water qualities on a regular basis. The purpose of this research is to design an ultraviolet water purification system that utilizes new ultraviolet LED technologies in order to provide potable drinking water. The intended purpose of this device is to be a long-lasting solution for areas in need. This is accomplished through the use of promising technologies such as solar photovoltaic modules and electrochemical double layered capacitors. A village size of 40 people was selected …

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Improving Label Prediction In Social Networks By Adding Noise, Praveen Kumar Gurumurthy Jan 2015

Improving Label Prediction In Social Networks By Adding Noise, Praveen Kumar Gurumurthy

Open Access Theses

Social Networks like Facebook and Linkedin have grown tremendously over the last

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Advanced Methods For Validating Combustion Instability Predictions Using Pressure Measurements, Yu Huang Jan 2015

Advanced Methods For Validating Combustion Instability Predictions Using Pressure Measurements, Yu Huang

Open Access Theses

The utility of high fidelity (HF) pressure measurements from Continuous Variable

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Using Topography To Aid Cell Phone Geolocation, Jaeyoung Kim Jan 2015

Using Topography To Aid Cell Phone Geolocation, Jaeyoung Kim

Open Access Theses

In daily life, people demand accuracy of the Global Positioning System (GPS) receiver. The current problem of GPS on mobile phones is that it is not available in areas such as urban, natural canyons, forests, and indoor environments. Several methods have been developed to obtain more accurate position estimation over the past years. The received signal strength (RSS) and time difference of arrival (TDOA) are the main approaches to use available mobile signals and errors around 4 ~ 12 dB and 10 ~ 60 meters, respectively. Another approach to make a better performance of the sensor is to use radio …

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Crash Analysis Of A Conceptual Electric Vehicle With A Multifunctional Battery System, Jaspreet Singh Kukreja Jan 2015

Crash Analysis Of A Conceptual Electric Vehicle With A Multifunctional Battery System, Jaspreet Singh Kukreja

Open Access Theses

For current electric vehicles, batteries are employed only as an energy source. Due to safety concerns, the space for battery storage is co-allocated with passenger space, which would constrain the design for the vehicle. An architectured multifunctional battery-structure material, namely Granular Battery Assembly (GBA), has been proposed by Tsutsui et al., 2014. Such a material system utilizes the deformation of sacrificing tubes to dissipate impact energy and protect the battery cells, thereby allowing the batteries to be placed in the front crumple zone of an electric vehicle, while also ensuring occupant safety.

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Industrial Adoption Of Model-Based Systems Engineering: Challenges And Strategies, Apoorv Maheshwari Jan 2015

Industrial Adoption Of Model-Based Systems Engineering: Challenges And Strategies, Apoorv Maheshwari

Open Access Theses

As design teams are becoming more globally integrated, one of the biggest challenges is to efficiently communicate across the team. The increasing complexity and multi-disciplinary nature of the products are also making it difficult to keep track of all the information generated during the design process by these global team members. System engineers have identified Model-based Systems Engineering (MBSE) as a possible solution where the emphasis is placed on the application of visual modeling methods and best practices to systems engineering (SE) activities right from the beginning of the conceptual design phases through to the end of the product lifecycle. …

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Stirlocharger Powered By Exhaust Heat For High Efficiency Combustion And Electric Generation, Adhiraj B. Mathur Jan 2015

Stirlocharger Powered By Exhaust Heat For High Efficiency Combustion And Electric Generation, Adhiraj B. Mathur

Open Access Theses

Stirling engines have been in existence since the early 1900s, and have been of little study in the recent years. Stirling engines are low power, heat engines which work on the principle of a temperature differential between the hot and cold sides. This thesis will look into the integration of a Stirling engine onto a turbocompressor for automotive applications calling the device a Stirlocharger.

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Evaluating Management Options: Simulating Wetland Processes And Performance Of Nutrient Reduction By Use Of A Water Quality Algorithm, Stuart David Smith Jan 2015

Evaluating Management Options: Simulating Wetland Processes And Performance Of Nutrient Reduction By Use Of A Water Quality Algorithm, Stuart David Smith

Open Access Theses

The effects of nutrient overloading have been well identified in areas such as the Gulf of Mexico, where agricultural drainage from the Midwest is considered a main contributor to the hypoxic zone. Amongst the suite of agricultural Best Management Practices (BMPs), managed wetlands may present a more cost effective approach to assimilate pollutants and improve water quality at the scale of small watersheds. However, previous research has yielded varying results. Mathematical models have become a tool used to characterize components and predict behaviors of a given process. Model results can then be used to analyze multiple management options, improve decision …

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Investigating The Impact Of Visuohaptic Simulations For The Conceptual Understanding Of Electric Field For Distributed Charges, Uzma Abdul Sattar Shaikh Jan 2015

Investigating The Impact Of Visuohaptic Simulations For The Conceptual Understanding Of Electric Field For Distributed Charges, Uzma Abdul Sattar Shaikh

Open Access Theses

The present study assessed the benefits of a multisensory intervention on the conceptual understanding of electric field for distributed charges in engineering and technology undergraduate students. A novel visuohaptic intervention was proposed, which focused on exploring the forces around the different electric field configurations for distributed charges namely point, infinitely long line and uniformly charged ring. The before and after effects of the visuohaptic intervention are compared, wherein the intervention includes instructional scaffolding. Three single-group studies were conducted to investigate the effect among three different populations: (a) Undergraduate engineering students, (b) Undergraduate technology students and (c) Undergraduate engineering technology students …

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Gaussian Processes With Built-In Dimensionality Reduction: Applications In High-Dimensional Uncertainty Quantification, Rohit Kaushal Tripathy Jan 2015

Gaussian Processes With Built-In Dimensionality Reduction: Applications In High-Dimensional Uncertainty Quantification, Rohit Kaushal Tripathy

Open Access Theses

Uncertainty quantification (UQ) tasks, such as model calibration, uncertainty propagation, and optimization under uncertainty, typically require several thousand evaluations of the underlying computer codes. To cope with the cost of simulations, one replaces the real response surface with a cheap surrogate based, e.g., on polynomial chaos expansions, neural networks, support vector machines, or Gaussian processes (GP). However, the number of simulations required to learn a generic multivariate response grows exponentially as the input dimension increases. This curse of dimensionality can only be addressed, if the response exhibits some special structure that can be discovered and exploited. A wide range of …

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Evaluating Engineering Learning And Gender Neutrality For The Product Design Of A Modular Robotic Kit, Ansh Verma Jan 2015

Evaluating Engineering Learning And Gender Neutrality For The Product Design Of A Modular Robotic Kit, Ansh Verma

Open Access Theses

The development of a system is informed from design factors in order to success- fully support the intended usability from the perceived affordances [1]. The theory of ‘Human Centered Design’ champions that these factors be derived from the user itself. It is based on exploiting these affordances that the boundary of technology is pushed to sometimes invent new methods or sometimes approach a problem from newer perspectives. This thesis is an example where we inform our design rationales from children in order to develop a gender neutral modular robotic toy kit.

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Constrained Optimized Command Shaping For Minimizing Residual Vibration In A Flexible-Joint Robot, Alok Agrawal Jan 2015

Constrained Optimized Command Shaping For Minimizing Residual Vibration In A Flexible-Joint Robot, Alok Agrawal

Open Access Theses

Joint flexibility is a natural trait of robotic manipulators, which limits fast point-to-point motion. Remedial measures are often employed to enable these systems to perform their goal in a desired manner. These measures range from either modifying the system dynamics such that the resonance is increasingly damped or by designing cleverly shaped input commands that avoid exciting the resonant modes altogether. In this work, a numerical framework for generating constrained shaped commands for a two-link flexible-joint robot is presented. To optimally select the design parameters for generating shaped commands, the effects of subjecting the optimization to mutually exhaustive constraints of …

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A Framework For Optimal Design Of Low-Power Fir Filters, Aparajita Banerjee Jan 2015

A Framework For Optimal Design Of Low-Power Fir Filters, Aparajita Banerjee

Open Access Theses

Approximate Computing has emerged as a new low-power design approach for application domains characterized by intrinsic error resilience. Digital Signal Processing (DSP) is one such domain where outputs of acceptable quality can be produced even though the internal computations are carried out in an approximate manner. With the ever increasing need for data rates at lower power usage; the need for improved complexity reduction schemes for DSP systems continues. One of the most widely performed steps in DSP is FIR filtering. FIR filters are preferred due to their linear

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Analysis And Simulation Of Nonlinearities In Noise Attenuation Model For A Diesel Engine Block, Jiajun Cao Jan 2015

Analysis And Simulation Of Nonlinearities In Noise Attenuation Model For A Diesel Engine Block, Jiajun Cao

Open Access Theses

The purpose of this thesis is to understand the characteristics of noise attenuation of a diesel engine block, by means of setting up a structural attenuation model and exploring the impact of variations of the model, in terms of nonlinearities. A model motivated by a set of experimentally-determined attenuation measurements was constructed, validated and explored for the potential for sound power prediction, with the aid of simulation.

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Sound Scattering Of An Obstacle Placed Near A Non-Locally Reacting Ground, Yiming Wang Jan 2015

Sound Scattering Of An Obstacle Placed Near A Non-Locally Reacting Ground, Yiming Wang

Open Access Theses

The Boundary Element Method (BEM) is widely used in outdoor sound scattering prob-lems due to its computational efficiency when compared to the FEM (FEM) for certain propagation geometries. The advantage of the BEM is apparent for problem geometries where the scattering surface is much smaller than the computational domain of the prob-lem. The Green's function can be used in the BEM formulation to represent a non-locally reacting porous ground surface. The Weyl Van der Pol formula is often used to accurately calculate the Green's functions above a locally reacting surface. However, the Green’s function representation for the sound field above …

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Hbsi Automation Using The Kinect 2, Zachary Edward Moore Jan 2015

Hbsi Automation Using The Kinect 2, Zachary Edward Moore

Open Access Theses

This research focused on classifying Human-Biometric Sensor Interaction errors in real-time. The Kinect 2 was used as a measuring device to track the position and movements of the subject through a simulated border control environment. Knowing, in detail, the state of the subject ensures that the human element of the HBSI model is analyzed accurately. A network connection was established with the iris device to know the state of the sensor and biometric system elements of the model. Information such as detection rate, extraction rate, quality, capture type, and more metrics was available for use in classifying HBSI errors. A …

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Morphological Plasticity Of Invasive Silver Carp In Divergent Midwestern Rivers, Katherine Flynn Touzinsky Jan 2015

Morphological Plasticity Of Invasive Silver Carp In Divergent Midwestern Rivers, Katherine Flynn Touzinsky

Open Access Theses

In the past decade, silver carp (SC; Hypopthalmicthys molitrix) have incited a great quantity of scientific research because their establishment and success in the Midwestern U.S. has led to concerns that they could invade the Great Lakes Basin. These previous studies have identified phenotypic plasticity in SC behavior and spawning as they invade novel environments. Although divergent habitats have been shown to elicit morphological plasticity in multiple fish species, similar research has not been conducted for SC despite their observed plasticity in other traits. I examined SC collected from two hydrogeomorphically divergent rivers, the Illinois River (IR) and middle Wabash …

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The Role Of Snow In Soil Thermal Dynamics Of The Arctic Terrestrial Ecosystems, Zhou Lyu Jan 2015

The Role Of Snow In Soil Thermal Dynamics Of The Arctic Terrestrial Ecosystems, Zhou Lyu

Open Access Theses

The vast area of permanent or seasonal snow cover is an essential component of terrestrial ecosystems in northern mid-to-high latitudes (45-90°N), which has insulation effects on the soil layer beneath it. The affected soil thermal regimes will impact soil carbon dynamics. Recent observations indicate that there are substantial changes in both snow cover extent and duration due to climate change in the area. It is important to understand the insulation effect historically so as to better quantify its role in affecting ecosystem carbon dynamics under changing climate in the future. This study incorporates the snow insulation effect by introducing a …

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Multiple-Cosmogenic-Nuclide Approaches To Studying The Holocene And Late Pleistocene History Of Small Ice Caps In Western Greenland, Casey Robert Beel Jan 2015

Multiple-Cosmogenic-Nuclide Approaches To Studying The Holocene And Late Pleistocene History Of Small Ice Caps In Western Greenland, Casey Robert Beel

Open Access Theses

This thesis contains two chapters; one dealing with long-term landscape evolution and late Quaternary ice sheet history along the western margin of the Greenland Ice Sheet (GIS), and the other with assessing the sensitivity of exposure durations calculated from paired bedrock 14C/10Be measurements in glacial troughs. Both chapters were designed to improve our understanding of the glacial history of Greenland.

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Torque Coefficients In Automotive Bolted Joint Assembly, Phuc Van Nguyen Jan 2015

Torque Coefficients In Automotive Bolted Joint Assembly, Phuc Van Nguyen

Open Access Theses

The thesis investigated the effects of four factors and their combinations on the torque coefficients of the first and second tightening of bolted joints by conducting a general full-factorial design with randomized blocks on 20 replications. The experiment involved three levels of tightening tool types, two levels of bolt dimensions, two levels of nut types, and two levels of plate type. The torque coefficients were calculated indirectly through the measuring the torque applied and bolt preload. The response variables studied were the mean and the variance between runs of the torque coefficients of the first tightening, as well as the …

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