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Full-Text Articles in Physical Sciences and Mathematics

On The 3d Point Cloud For Human-Pose Estimation, Kai-Chi Chan Apr 2016

On The 3d Point Cloud For Human-Pose Estimation, Kai-Chi Chan

Open Access Dissertations

This thesis aims at investigating methodologies for estimating a human pose from a 3D point cloud that is captured by a static depth sensor. Human-pose estimation (HPE) is important for a range of applications, such as human-robot interaction, healthcare, surveillance, and so forth. Yet, HPE is challenging because of the uncertainty in sensor measurements and the complexity of human poses. In this research, we focus on addressing challenges related to two crucial components in the estimation process, namely, human-pose feature extraction and human-pose modeling.

In feature extraction, the main challenge involves reducing feature ambiguity. We propose a 3D-point-cloud feature called …


Rank Constrained Homotopies Of Matrices And The Blackadar-Handelman Conjectures On C*-Algebras, Kaushika De Silva Apr 2016

Rank Constrained Homotopies Of Matrices And The Blackadar-Handelman Conjectures On C*-Algebras, Kaushika De Silva

Open Access Dissertations

Rank constrained homotopies of matrices:

For any n ≥ k ≥ l ∈ N, let S( n,k,l) be the set of all non-negative definite matrices a ∈ Mn(C) with l ≤ rank a ≤ k. We investigate homotopy equivalence of continuous maps from a compact Hausdorff space X into sets of the form S(n,k,l). From [37] it is known that for any n, if 4dim X ≤ k-l where dim X denote the covering dimension of X, then there is exactly one homotopy class of maps from X into S …


Is Metabolism Goal-Directed? Investigating The Validity Of Modeling Biological Systems With Cybernetic Control Via Omic Data, Frank T. Devilbiss Apr 2016

Is Metabolism Goal-Directed? Investigating The Validity Of Modeling Biological Systems With Cybernetic Control Via Omic Data, Frank T. Devilbiss

Open Access Dissertations

Cybernetic models are uniquely juxtaposed to other metabolic modeling frameworks in that they describe the time-dependent regulation of cellular reactions in terms of dynamic "metabolic goals." This approach contrasts starkly with purely mechanistic descriptions of metabolic regulation which seek to explain metabolic processes in high resolution — a clearly daunting undertaking. Over a span of three decades, cybernetic models have been used to predict metabolic phenomena ranging from resource consumption in mixed-substrate environments to intracellular reaction fluxes of intricate metabolic networks. While the cybernetic approach has been validated in its utility for the prediction of metabolic phenomena, its central feature, …


Crop Modeling For Assessing And Mitigating The Impacts Of Extreme Climatic Events On The Us Agriculture System, Zhenong Jin Apr 2016

Crop Modeling For Assessing And Mitigating The Impacts Of Extreme Climatic Events On The Us Agriculture System, Zhenong Jin

Open Access Dissertations

The US agriculture system is the world’s largest producer of maize and soybean, and typically supplies more than one-third of their global trading. Nearly 90% of the US maize and soybean production is rainfed, thus is susceptible to climate change stressors such as heat waves and droughts. Process-based crop and cropping system models are important tools for climate change impact assessments and risk management. As data- science is becoming a new frontier for agriculture growth, the incoming decade calls for operational platforms that use hyper-local growth monitoring, high-resolution real-time weather and satellite data assimilation and cropping system modeling to help …


Present Day Plate Boundary Deformation In The Caribbean And Crustal Deformation On Southern Haiti, Steeve Symithe Apr 2016

Present Day Plate Boundary Deformation In The Caribbean And Crustal Deformation On Southern Haiti, Steeve Symithe

Open Access Dissertations

The Caribbean plate and its boundaries with North and South America, marked by subduction and large intra-arc strike-slip faults, are a natural laboratory for the study of strain partitioning and interseismic plate coupling in relation to large earth- quakes. In this work, I use the available campaign and continuous GPS measurements in the Caribbean to derive a regional velocity field expressed in a consistent reference frame. I use this velocity field as input to a kinematic model where surface velocities result from the rotation of rigid blocks bounded by locked faults accumulating inter- seismic strain, while allowing for partial locking …


Optimal Monitoring And Mitigation Of Systemic Risk In Lending Networks, Zhang Li Apr 2016

Optimal Monitoring And Mitigation Of Systemic Risk In Lending Networks, Zhang Li

Open Access Dissertations

This thesis proposes optimal policies to manage systemic risk in financial networks. Given a one-period borrower-lender network in which all debts are due at the same time and have the same seniority, we address the problem of allocating a fixed amount of cash among the nodes to minimize the weighted sum of unpaid liabilities. Assuming all the loan amounts and cash flows are fixed and that there are no bankruptcy costs, we show that this problem is equivalent to a linear program. We develop a duality-based distributed algorithm to solve it which is useful for applications where it is desirable …


Climate Change And Hazardous Convective Weather In The United States: Insights From High-Resolution Dynamical Downscaling, Kimberly A. Hoogewind Apr 2016

Climate Change And Hazardous Convective Weather In The United States: Insights From High-Resolution Dynamical Downscaling, Kimberly A. Hoogewind

Open Access Dissertations

Global climate model (GCM) projections increasingly suggest that large-scale environmental conditions favorable for hazardous convective weather (HCW) may increase in frequency in the future due to anthropogenic climate change. However, this storm environment-based approach is undoubtedly limited by the assumption that convective-scale phenomena will be realized within these environments. The spatial resolution of GCMs remains much too coarse to adequately represent the scales at which severe convective storms occur, including processes that may lead to storm initiation. With the advancement of computing resources, however, it has now become feasible to explicitly represent deep convective storms within a high-resolution regional climate …


Kernels Of Adjoints Of Composition Operators On Hilbert Spaces Of Analytic Functions, Brittney Rachele Miller Apr 2016

Kernels Of Adjoints Of Composition Operators On Hilbert Spaces Of Analytic Functions, Brittney Rachele Miller

Open Access Dissertations

This thesis contains a collection of results in the study of the adjoint of a composition operator and its kernel in weighted Hardy spaces, in particular, the classical Hardy, Bergman, and Dirichlet spaces. In 2006, Cowen and Gallardo-Gutiérrez laid the groundwork for an explicit formula for the adjoint of a composition operator with rational symbol acting on the Hardy space, and in 2008, Hammond, Moorhouse, and Robbins established such a formula. In 2014, Goshabulaghi and Vaezi obtained analogous formulas for the adjoint of a composition operator in the Bergman and Dirichlet spaces. While it is known that the kernel of …


Energy Efficiency In Data Collection Wireless Sensor Networks, Miquel Andres Navarro Patino Apr 2016

Energy Efficiency In Data Collection Wireless Sensor Networks, Miquel Andres Navarro Patino

Open Access Dissertations

This dissertation studies the problem of energy efficiency in resource constrained and heterogeneous wireless sensor networks (WSNs) for data collection applications in real-world scenarios. The problem is addressed from three different perspectives: network routing, node energy profiles, and network management. First, the energy efficiency in a WSN is formulated as a load balancing problem, where the routing layer can diagnose and exploit the WSN topology redundancy to reduce the data traffic processed in critical nodes, independent of their hardware platform, improving their energy consumption and extending the network lifetime. We propose a new routing strategy that extends traditional cost-based routing …


Monotonicity Formulas For Diffusion Operators On Manifolds And Carnot Groups, Heat Kernel Asymptotics And Wiener's Criterion On Heisenberg-Type Groups, Kevin L. Rotz Apr 2016

Monotonicity Formulas For Diffusion Operators On Manifolds And Carnot Groups, Heat Kernel Asymptotics And Wiener's Criterion On Heisenberg-Type Groups, Kevin L. Rotz

Open Access Dissertations

The contents of this thesis are an assortment of results in analysis and subRiemannian geometry, with a special focus on the Heisenberg group Hn, Heisenbergtype (H-type) groups, and Carnot groups.

As we wish for this thesis to be relatively self-contained, the main definitions and background are covered in Chapter 1. This includes basic information about Carnot groups, Hn, H-type groups, diffusion operators, and the curvature dimension inequality.

Chapter 2 incorporates excerpts from a paper by N. Garofalo and the author, [42]. In it, we propose a generalization of Almgren’s frequency function N : (0, 1) → R for solutions to …


Finite Dimensional Approximations And Deformations Of Group C*-Algebras, Andrew James Schneider Apr 2016

Finite Dimensional Approximations And Deformations Of Group C*-Algebras, Andrew James Schneider

Open Access Dissertations

Quasidiagonality is a finite-dimensional approximation property of a C*-algebra which indicates that it has matricial approximations that capture the structure of the C*-algebra. We investigate when C*-algebras associated to discrete groups have such a property with particular emphasis on finding obstructions. In particular, we point out that groups with Kazhdan's Property (T) and only finitely many unitary equivalence classes of finite dimensional representations do not produce quasidiagonal C*-algebras. We then observe and note interactions with Property (T) and other approximation properties.

Property (QH) is a related but stronger approximation property with deep connections to E-Theory and …


An Evaluation Of Noise Reduction Strategies At Large Commercial Airports In The United States: A Policy Analysis And Framework Classification, Tyler Spence Apr 2016

An Evaluation Of Noise Reduction Strategies At Large Commercial Airports In The United States: A Policy Analysis And Framework Classification, Tyler Spence

Open Access Dissertations

Noise pollution from aircraft, specifically in the vicinity of airports as aircraft takeoff and land, is a problem that has been shown to have negative impacts on the welfare of humans, animals, and the surrounding environment. The problem may only become worse as air travel increases for cargo and passenger operations, populations increase, and the overall number of aircraft increase. Currently, guidance has been issued from the International Civil Aviation Organization on how to combat the issue of noise pollution through policy, both at that national regulatory level, and at the local airport level. This study evaluated the local airport …


Direct Drug Screening And Lipid Profiling Using Ambient Mass Spectrometry, Yuan Su Apr 2016

Direct Drug Screening And Lipid Profiling Using Ambient Mass Spectrometry, Yuan Su

Open Access Dissertations

Mass spectrometry (MS) stands in an outstanding position in analysis of biological specimens owing to its abundant structural information, high accuracy, incomparable sensitivity, high speed, and the large variety of its applications. The ion source, an instrumental part for converting the analyte into ions, has played an important role in analyzing biological specimens by MS. However, the performance of conventional spray-based ionization methods always suffers from chemical interferences derived from complex biological matrices. A series of sample extraction, purification, and separation steps is required before the ionization, so as to ensure excellent performance of MS analysis. In order to simplify …


Behavioral Responses And Policy Evaluation: Revisiting Water And Fuel Policies, Shanxia Sun Apr 2016

Behavioral Responses And Policy Evaluation: Revisiting Water And Fuel Policies, Shanxia Sun

Open Access Dissertations

In my dissertation, I examine how policies regulating agricultural production and clean technology impact the environment. I focus on policies affecting water depletion, water pollution, and fuel consumption. I assess their cost-effectiveness by modeling and quantifying the behavioral responses of farmers and households.

My first essay focuses on decreasing groundwater depletion through increasing irrigation efficiency in Mexico. I quantify the impacts of different sources of inefficiency on groundwater extraction, and I evaluate the effectiveness of alternative policies that aim to reduce the over-extraction of groundwater. I find that mechanisms of electricity cost-sharing implemented in many wells have a sizable impact …


Implementation And Validation Of A Probabilistic Open Source Baseball Engine (Posbe): Modeling Hitters And Pitchers, Rhett Tracy Schaefer Apr 2016

Implementation And Validation Of A Probabilistic Open Source Baseball Engine (Posbe): Modeling Hitters And Pitchers, Rhett Tracy Schaefer

Open Access Theses

This manuscript details the implementation and validation of an open source probabilistic baseball engine (POSBE) that focuses on the hitter and pitcher model of the simulation. The simulation produced outcomes that parallel those observed in actual professional Major League Baseball games. The observed data were taken from the nineteen games played between the New York Yankees (NYY) and Boston Red Sox (BOS) during the 2015 season. The potential hitter/pitcher outcomes of interest were singles, doubles, triples, homeruns, walks, hit-by-pitch, and strikeouts. The nineteen game series was simulated 1000 times, resulting in a total of 19,000 simulations. The eighteen hitters and …


Gesture Based Non-Obstacle Interaction On Mobile Computing Devices For Dirty Working Environment, William B. Huynh Apr 2016

Gesture Based Non-Obstacle Interaction On Mobile Computing Devices For Dirty Working Environment, William B. Huynh

Open Access Theses

The dominant way of interacting with tablets, smartphones, or wearable devices are through touchscreen or touchpad, which requires the user to physically touch the device’s screen. However, in certain situation, for example, a dirty working environment, touching is not ideal or feasible. This study examined a new method that allows for a non-touch interaction by using the devices’ back camera along with simple gesture to simulate mouse clicking. Cameras are used to capture motion-based gestures coupled with object detection, achieving a non-touch interaction. With human subject evaluation, the researcher found that using the back camera on mobile devices for gesture …


A Study Of How Chinese Ink Painting Features Can Be Applied To 3d Scenes And Models In Real-Time Rendering, Muning Cao Apr 2016

A Study Of How Chinese Ink Painting Features Can Be Applied To 3d Scenes And Models In Real-Time Rendering, Muning Cao

Open Access Theses

Past research findings addressed mature techniques for non-photorealistic rendering. However, research findings indicate that there is little information dealing with efficient methods to simulate Chinese ink painting features in rendering 3D scenes. Considering that Chinese ink painting has achieved many worldwide awards, the potential to effectively and automatically develop 3D animations and games in this style indicates a need for the development of appropriate technology for the future market.

The goal of this research is about rendering 3D meshes in a Chinese ink painting style which is both appealing and realistic. Specifically, how can the output image appear similar to …


Developing Probability Maps For Locating And Scouting Unprotected Areas Of Gravel Hill Prairies On Rodman Soils Along The Wabash River Valley Near Lafayette, Indiana, Ryan W.R. Schroeder Mar 2016

Developing Probability Maps For Locating And Scouting Unprotected Areas Of Gravel Hill Prairies On Rodman Soils Along The Wabash River Valley Near Lafayette, Indiana, Ryan W.R. Schroeder

Engagement & Service-Learning Summit

No abstract provided.


Managing Your Professional Identity: Leveraging Social Media And Emerging Metrics To Demonstrate Professional Impact, Megan R. Sapp Nelson Mar 2016

Managing Your Professional Identity: Leveraging Social Media And Emerging Metrics To Demonstrate Professional Impact, Megan R. Sapp Nelson

Libraries Faculty and Staff Presentations

This session will assist graduate students to deliberately develop an online professional identity that will uniquely identify them as an academic as well as positively highlight their personal strengths.

Students will walk away with a plan to create a unique professional identifier and an understanding of how to measure the impact of online scholarly communication.

Topics included are:

ORCID ID

social media, such as LinkedIn & ResearchGate

Alternative Metrics (Altmetrics), such has Kudos, ImpactStory, & AltMetric

Data repositories, such as GitHub & FigShare


Hydrologic And Water Quality Impacts From Perennial Crop Production On Marginal Lands, Qingyu Feng Mar 2016

Hydrologic And Water Quality Impacts From Perennial Crop Production On Marginal Lands, Qingyu Feng

Open Access Dissertations

Marginal lands are proposed as a viable option for producing biofeedstocks as these lands are not heavily engaged in agricultural production or may not be suitable for intensive row-crop food/feed production. However, meeting biofeedstock production goals will require large amount of marginal lands and the unintended consequences of producing biofeedstocks on marginal lands are not fully clear. The overall goal of this study was to evaluate the productivity of biofeedstocks on marginal lands and the potential impacts on hydrologic and water quality processes from the land use conversion.

This study was conducted in the Upper Mississippi River Basin (UMRB). First, …


Sequential Pattern Mining With Uncertain Data, Jiaqi Ge Mar 2016

Sequential Pattern Mining With Uncertain Data, Jiaqi Ge

Open Access Dissertations

In recent years, a number of emerging applications, such as sensor monitoring systems, RFID networks and location based services, have led to the proliferation of uncertain data. However, traditional data mining algorithms are usually inapplicable in uncertain data because of its probabilistic nature. Uncertainty has to be carefully handled; otherwise, it might significantly downgrade the quality of underlying data mining applications.

Therefore, we extend traditional data mining algorithms into their uncertain versions so that they still can produce accurate results. In particular, we use a motivating example of sequential pattern mining to illustrate how to incorporate uncertain information in the …


The Search For Dark Matter Annihilation In Galaxy Clusters At Veritas, James V. Tucci Mar 2016

The Search For Dark Matter Annihilation In Galaxy Clusters At Veritas, James V. Tucci

Open Access Dissertations

Recent data and cosmological models point to a significant fraction of the Universe being comprised of Cold Dark Matter (DM), though little is known about it directly as it does not interact electromagnetically. The most likely explanation for DM is a Weakly Interacting Massive Particle (WIMP) having a mass as low as ∼10 GeV to as high as ∼10 TeV. WIMPs are believed to be their own antiparticles and self-annihilate into a variety of lighter particles including γ-rays. Many direct detection, indirect detection, and direct production schemes have been proposed to search for the elusive WIMP. Galaxy clusters, consisting of …


Thermal Neutron Analysis For Improvised Explosive Device Detection, Matthew David Marziale Mar 2016

Thermal Neutron Analysis For Improvised Explosive Device Detection, Matthew David Marziale

Open Access Dissertations

In this dissertation, the design of a system to detect improvised explosive devices is considered. The technique utilized is thermal neutron analysis. In this method, thermal neutrons are used to interrogate a volume for the presence of nitrogen, which is used as an indicator of explosive, given its unusual high energy line in the gamma ray spectrum generated by thermal capture reactions on explosive material. The performance of the system is then considered for a number of devices used to represent an improvised explosive device, including a 155 mm shell, an antitank mine, and a air to surface bomb. The …


Supervised Learning-Based Explicit Nonlinear Model Predictive Control And Unknown Input Estimation In Biomedical Systems, Ankush Chakrabarty Feb 2016

Supervised Learning-Based Explicit Nonlinear Model Predictive Control And Unknown Input Estimation In Biomedical Systems, Ankush Chakrabarty

Open Access Dissertations

Application of nonlinear control theory to biomedical systems involves tackling some unique and challenging problems. The mathematical models that describe biomedical systems are typically large and nonlinear. In addition, biological systems exhibit dynamics which are not reflected in the model (so-called 'un-modeled dynamics') and hard constraints on the states and control actions, which exacerbate the difficulties in designing model-based controllers or observers.

This thesis investigates the design of scalable fast explicit nonlinear model predictive controllers (ENMPCs). The design involves (i) the estimation of a feasible region using Lyapunov stability methods and support vector machines; and (ii) within the estimated feasible …


A Flexible And Versatile Framework For Statistical Design And Analysis Of Quantitative Mass Spectrometry-Based Proteomic Experiments, Meena Choi Feb 2016

A Flexible And Versatile Framework For Statistical Design And Analysis Of Quantitative Mass Spectrometry-Based Proteomic Experiments, Meena Choi

Open Access Dissertations

Quantitative mass spectrometry (MS)-based proteomics is an indispensable technology for biological and clinical research. As the proteomics field grows, MS-based proteomic workflows are becoming more complex and diverse. The accuracy and the throughput of the MS measurements and of the signal processing tools dramatically increased. However, many existing statistical tools and workflows have not followed the technological development. Therefore, there is a need for flexible statistical tools, which reflect diverse and complex workflows, are computationally efficient for large datasets, and maximize the reproducibility of the results.

We propose a family of linear mixed effects models, and a split-plot view of …


The Basic Competencies Of Biological Experimentation: Concept-Skill Statements, Nancy Pelaez, Trevor Anderson, Stephanie M. Gardner, Yue Yin, Joel K. Abraham, Edward Bartlett, Cara Gormally, Jeffrey P. Hill, Mildren Hoover, Carol Hurney, Tammy Long, Dina L. Newman, Karen Sirum, Michael Stevens Jan 2016

The Basic Competencies Of Biological Experimentation: Concept-Skill Statements, Nancy Pelaez, Trevor Anderson, Stephanie M. Gardner, Yue Yin, Joel K. Abraham, Edward Bartlett, Cara Gormally, Jeffrey P. Hill, Mildren Hoover, Carol Hurney, Tammy Long, Dina L. Newman, Karen Sirum, Michael Stevens

PIBERG Instructional Innovation Materials

This biological experimentation competencies map is a model created by members of the ACE-Bio Network of seven areas a competent biologist calls in when doing experimentation in biology. Each competency is represented by a summary word on a uniquely colored segment of the model. For presentation convenience, the seven major areas within experimentation in biology are mapped onto tables in a linear manner. However, this is not meant to convey a particular order that one must follow during experimentation. The areas are given equal weight and flexible order of their use throughout the process of experimentation. This work is meant …


Tailoring Optical And Plasmon Resonances In Core-Shell And Core-Multishell Nanowires, Sarath Ramadurgam Jan 2016

Tailoring Optical And Plasmon Resonances In Core-Shell And Core-Multishell Nanowires, Sarath Ramadurgam

Open Access Dissertations

Semiconductor nanowires (NWs) are sub-wavelength structures which exhibit strong optical (Mie) resonances in the visible range. In addition to such optical resonances, the localized surface plasmon resonances (LSPR) in metal and semiconductor (or dielectric) based core-shell (CS) and core-multishell (CMS) NWs can be tailored to achieve novel negative-index metamaterials (NIM), extreme absorbers, invisibility cloaks and sensors. Particularly, in this dissertation, the versatility of CS and CMS NWs for the design of negative-index metamaterials in the visible range and, plasmonic light harvesting in ultrathin photocatalyst layers for water splitting are studied.

Utilizing the LSPR in the metal layer and the magnetic …


A Study Of Alterations In Dna Epigenetic Modifications (5mc And 5hmc) And Gene Expression Influenced By Simulated Microgravity In Human Lymphoblastoid Cells, Basudev Chowdhury, Arun Seetharam, Zhiping Wang, Yunlong Liu, Amy C. Lossie, Jyothi Thimmapuram Jan 2016

A Study Of Alterations In Dna Epigenetic Modifications (5mc And 5hmc) And Gene Expression Influenced By Simulated Microgravity In Human Lymphoblastoid Cells, Basudev Chowdhury, Arun Seetharam, Zhiping Wang, Yunlong Liu, Amy C. Lossie, Jyothi Thimmapuram

Cyber Center Publications

Cells alter their gene expression in response to exposure to various environmental changes. Epigenetic mechanisms such as DNA methylation are believed to regulate the alterations in gene expression patterns. In vitro and in vivo studies have documented changes in cellular proliferation, cytoskeletal remodeling, signal transduction, bone mineralization and immune deficiency under the influence of microgravity conditions experienced in space. However microgravity induced changes in the epigenome have not been well characterized. In this study we have used Next-generation Sequencing (NGS) to profile ground-based “simulated” microgravity induced changes on DNA methylation (5-methylcytosine or 5mC), hydroxymethylation (5-hydroxymethylcytosine or 5hmC), and simultaneous gene …


Size And Chemistry Selective Membranes From Block Polymer Templates, Ryan A. Mulvenna Jan 2016

Size And Chemistry Selective Membranes From Block Polymer Templates, Ryan A. Mulvenna

Open Access Dissertations

The use of block polymers continues to gain attention with their myriad applications in industry for advanced applications in biology, medicine, electronics, and separations. The ability of block polymers to self assemble into ordered states on the nanometer level makes these materials suitable for applications that mandate structural order on this scale. By tuning the chemistry of these block domains, we may explore their utilization for advanced separations.

In this dossier, we detail the efforts into the controlled radical polymerization of polyisoprene-b-polystyrene-b-poly( N,N-dimethylacrylamide) (PI-PS-PDMA) via. a facile reversible addition-fragmentation chain transfer (RAFT) mechanism. For this …


Electric Power And The Global Economy: Advances In Database Construction And Sector Representation, Jeffrey C. Peters Jan 2016

Electric Power And The Global Economy: Advances In Database Construction And Sector Representation, Jeffrey C. Peters

Open Access Dissertations

The electricity sector plays a crucial role in the global economy. The sector is a major consumer of fossil fuel resources, producer of greenhouse gas emissions, and an important indicator and correlate of economic development. As such, the sector is a primary target for policy-makers seeking to address these issues. The sector is also experiencing rapid technological change in generation (e.g. renewables), primary inputs (e.g. horizontal drilling and hydraulic fracturing), and end-use efficiency. This dissertation seeks to further our understanding of the role of the electricity sector as part of the dynamic global energy-economy, which requires significant research advances in …