Physical Sciences and Mathematics Commons^™

Confidence Bands For Survival Curves Using Model Assisted Cox Regression, Shoubhik Mondal

Dissertations

The goal of this dissertation is to develop informative subject-specific simultaneous confidence bands (SCBs) for survival functions from right censored data. The approach is based on an extension of semiparametric random censorship models (SRCMs) to Cox regression, which produces reliable and more informative SCBs. SRCMs derive their rationale from their ability to utilize parametric ideas within the random censorship environment. Incorporating SRCMs into the existing framework produces more powerful procedures to analyze right censored data. The first part of the project focuses on proposing new estimators of Cox regression parameters and the cumulative baseline hazard function, and deriving their large …

New Directions For Remote Data Integrity Checking Of Cloud Storage, Bo Chen

Dissertations

Cloud storage services allow data owners to outsource their data, and thus reduce their workload and cost in data storage and management. However, most data owners today are still reluctant to outsource their data to the cloud storage providers (CSP), simply because they do not trust the CSPs, and have no confidence that the CSPs will secure their valuable data. This dissertation focuses on Remote Data Checking (RDC), a collection of protocols which can allow a client (data owner) to check the integrity of data outsourced at an untrusted server, and thus to audit whether the server fulfills its contractual …

Intent-Based User Segmentation With Query Enhancement, Wei Xiong

Dissertations

With the rapid advancement of the internet, accurate prediction of user's online intent underlying their search queries has received increasing attention from the online advertising community. As a rich source of information on web user's behavior, query logs have been leveraged by advertising companies to deliver personalized advertisements. However, a typical query usually contains very few terms, which only carry a small amount of information about a user's interest. The tendency of users to use short and ambiguous queries makes it difficult to fully describe and distinguish a user's intent. In addition, the query feature space is sparse, as only …

Efficient Domain Decomposition Algorithms For The Solution Of The Helmholtz Equation, Dawid Midura

Dissertations

The purpose of this thesis is to formulate and investigate new iterative methods for the solution of scattering problems based on the domain decomposition approach. This work is divided into three parts. In the first part, a new domain decomposition method for the perfectly matched layer system of equations is presented. Analysis of a simple model problem shows that the convergence of the new algorithm is guaranteed provided that a non-local, square-root transmission operator is used. For efficiency, in practical simulations such operators need to be localized. Current, state of the art domain decomposition algorithms use the localization technique based …

The Experience Of Reducing Environmental Risks In An Environmental Justice Community, Gabriela Dory

Dissertations

Research on Environmental Justice (EJ) communities has focused on quantitative assessment of environmental hazards and general physical health problems. Little is known about how individuals living in EJ communities perceive their environmental risks and how they reduce environmental risks. The purpose of the study is to explore and describe the perceived environmental risks and the experience of reducing environmental risk among individuals living in an EJ community.

A qualitative and longitudinal design with a descriptive phenomenological method is used to recruit 23 participants living in a known EJ community in the urban area of New Jersey. A total of 43 …

The Control Of The False Discovery Rate Under Structured Hypotheses, Gavin Lynch

Dissertations

The hypotheses in many multiple testing problems often have some inherent structure based on prior information such as Gene Ontology in gene expression data. However, few false discovery rate (FDR) controlling procedures take advantage of this inherent structure. In this dissertation, we develop FDR controlling methods which exploit the structural information of the hypotheses.

First, we study the fixed sequence structure where the testing order of the hypotheses has been pre-specified. We are motivated to study this structure since it is the most basic of structures, yet, it has been largely ignored in the literature on large scale multiple testing. …

Electro-Deformation Of A Moving Boundary: A Drop Interface And A Lipid Bilayer Membrane, Herve Nganguia

Dissertations

This dissertation focuses on the deformation of a viscous drop and a vesicle immersed in a (leaky) dielectric fluid under an electric field. A number of mathematical tools, both analytical and numerical, are developed for these investigations. The dissertation is divided into three parts. First, a large-deformation model is developed to capture the equilibrium deformation of a viscous spheroidal drop covered with non-diffusing insoluble surfactant under a uniform direct current (DC) electric field. The large- deformation model predicts the dependence of equilibrium spheroidal drop shape on the permittivity ratio, conductivity ratio, surfactant coverage, and the elasticity number. Results from the …

Data Analysis And Simulation For Warranties And Golf Handicaps, Sonia Bandha

Dissertations

In this dissertation, we discuss the application of data analysis and numerical simulation in order to gain insight into problems related to warranty cost management and the effectiveness of the golf handicap system. Despite the commonalities of the approaches, we will discuss these problems in turn.

For many moderately high value items with a substantial sales volume (such as automobiles), a warranty is used as an important element of marketing products as a better warranty typically signals higher product quality to customers. Much recent research on modeling and optimization of servicing costs for Non-Renewing Free Replacement Warranties (NR-FRW) assumes that …

Fwer Controlling Procedures For Testing Multiple Hypotheses With Hierarchical Structure And Applications In Clinical Trials, Zhiying Qiu

Dissertations

In applications of clinical trials, the hypotheses to be tested often exhibit a hierarchical structure, and are usually hierarchically ordered based on their importance, clinical relevance, or dose concentration, etc. Thus, they are tested in a pre-defined fixed sequence. In some more complex cases, the hypotheses to be tested are hierarchically grouped into several families, and thus the families are tested in a sequential order. Although such problems of structured multiple testing have received much attention and several popular FWER controlling procedures, such as conventional fixed sequence procedure, fallback procedure and gatekeeping procedure have been introduced, not much progress has …

Computational Methods For The Analysis Of Next Generation Sequencing Data, Wei Wang

Dissertations

Recently, next generation sequencing (NGS) technology has emerged as a powerful approach and dramatically transformed biomedical research in an unprecedented scale. NGS is expected to replace the traditional hybridization-based microarray technology because of its affordable cost and high digital resolution. Although NGS has significantly extended the ability to study the human genome and to better understand the biology of genomes, the new technology has required profound changes to the data analysis. There is a substantial need for computational methods that allow a convenient analysis of these overwhelmingly high-throughput data sets and address an increasing number of compelling biological questions which …

Investigation Of New Feature Descriptors For Image Search And Classification, Atreyee Sinha

Dissertations

Content-based image search, classification and retrieval is an active and important research area due to its broad applications as well as the complexity of the problem. Understanding the semantics and contents of images for recognition remains one of the most difficult and prevailing problems in the machine intelligence and computer vision community. With large variations in size, pose, illumination and occlusions, image classification is a very challenging task. A good classification framework should address the key issues of discriminatory feature extraction as well as efficient and accurate classification. Towards that end, this dissertation focuses on exploring new image descriptors by …

Analysis Of Far-Infrared Optical Spectra Of Multiferroics, Eric C. Standard

Dissertations

The optical spectra of multiferroic crystals Dy₃Fe₅O₁₂, Tb₃Fe₅O₁₂, and four hexagonal RMnO₃ (5D= Er, Tm, Yb, Lu) are studied using intense bright synchrotonic light in the infrared spectral range. In regards to the materials analyzed, two rare earth iron garnets and four rare earth manganites in total are examined. These materials have attracted much attention due to their interesting magnetoelectric properties. They could serve as the basis for the next generation of faster and more energy efficient memory and logic devices. To examine these materials, two …

Nanocarbon Immobilized Membrane For Separation And Analysis, Madhuleena Bhadra

Dissertations

Membrane processes classically cover a wide range of applications associated with various aspects of separation and purification. Over the last few years, membrane based processes have received much interest due to their compact and modular architecture, low energy consumption and cost effective separation. With the development of diverse nanomaterials which can serve as nanosorbents, or provide specific morphology for selective solute transport, recent years have witnessed the emergence of nanocarbon based membranes that can address some of the limitations of conventional membrane processes and make feasible the next generation of breakthroughs.

The objective of this research is the exploration of …

Inverse Methods For Sound Speed Estimation In The Ocean, Tao Lin

Dissertations

This dissertation presents theoretical and computational approaches for estimating sound-speed in the ocean under different conditions. The first part of the dissertation discusses a fast approach for solving the inverse problem of estimating sediment sound-speed based on the Deift-Trubowitz trace formula. Under certain assumptions, this algorithm can recover the sound speed profile in the seabed using pressure field measurements in the water column at low frequencies. The inversion algorithm requires solving a non-linear integral equation. In the past, Stickler and Zhou employed a first order Born approximation for solving the integral equation. This work introduces two new methods. The first …

Risk Prediction With Genomic Data, Bharati Jadhav

Theses

Genome wide association study (GWAS) is widely used with various machine learning algorithms to predict disease risk. This thesis investigates this widely used approach of GWAS using Single Nucleotide Polymorphism (SNP) genotype data and a novel approach of disease risk prediction with whole exome sequencing data, namely Whole Exome Wide Association Study (WEWAS). It further applies a discriminating machine learning algorithm, namely a Support Vector Machine (SVM) with different Kernel functions. For this study, only SNPs generated using genotyping technology, which focuses more on common variants, are used initially for disease prediction. Later, the whole exome data generated using Next …

Dynamics Of Phase Locking In Neuronal Networks In The Presence Of Synaptic Plasticity, Zeynep Akcay

Dissertations

The behavior generated by neuronal networks depends on the phase relationships of its individual neurons. Observed phases result from the combined effects of individual cells and synaptic connections whose properties change dynamically. The properties of individual cells and synapses can often be characterized by driving the cell or synapse with inputs that arrive at different phases or frequencies, thus producing a feed-forward description of these properties. In this study, a recurrent network of two oscillatory neurons that are coupled with reciprocal synapses is considered. Feed-forward descriptions of the phase response curves of the neurons and the short-term synaptic plasticity properties …

Nanocarbons As Charge Carriers In Organic Solar Cells, Xinbo C. Lau

Dissertations

Organic photovoltaics (OPV) are an alternate to conventional silicon and thin film solar cells. They have several advantages such as simple fabrication, low material cost, light weight, and the ability to cover large areas. Typical OPV are based on bulk heterojunction structure consisting of a blend of an electron-donating semiconductor polymer and an electron-accepting molecule. Various approaches have been pursued to improve the performance of OPV: low bandgap polymers, new electron acceptors, processing additives, and tandem cell architecture.

Nanocarbons possess unique physical and chemical properties that can contribute to the enhancement of OPV performance, such as charge carrier mobility, thermal …

Increasing Adolescent Interest In Computing Through The Use Of Social Cognitive Career Theory, Osama Eljabiri

Dissertations

While empirical research efforts are sufficient to provide evidence of the role of most constructs in the Social Cognitive Career Theory (SCCT), this dissertation shifts the research focus and finds serious shortcomings in defining the construct of computer technology learning experiences design.

The purpose of this dissertation is to investigate whether, and to what extent, the proposed SCCT-enhanced framework can increase self-efficacy and interest of pre-college and college students in computer-based technology through the newly proposed “Learning Experiences” construct; in particular, whether it can reduce the gender gaps.

As a result of a comprehensive literature review, the dissertation connects learning, …

Innovative Local Texture Descriptors With Application To Eye Detection, Jiayu Gu

Dissertations

Local Binary Patterns (LBP), which is one of the well-known texture descriptors, has broad applications in pattern recognition and computer vision. The attractive properties of LBP are its tolerance to illumination variations and its computational simplicity. However, LBP only compares a pixel with those in its own neighborhood and encodes little information about the relationship of the local texture with the features. This dissertation introduces a new Feature Local Binary Patterns (FLBP) texture descriptor that can compare a pixel with those in its own neighborhood as well as in other neighborhoods and encodes the information of both local texture and …

Svmaud: Using Textual Information To Predict The Audience Level Of Written Works Using Support Vector Machines, Todd Will

Dissertations

Information retrieval systems should seek to match resources with the reading ability of the individual user; similarly, an author must choose vocabulary and sentence structures appropriate for his or her audience. Traditional readability formulas, including the popular Flesch-Kincaid Reading Age and the Dale-Chall Reading Ease Score, rely on numerical representations of text characteristics, including syllable counts and sentence lengths, to suggest audience level of resources. However, the author’s chosen vocabulary, sentence structure, and even the page formatting can alter the predicted audience level by several levels, especially in the case of digital library resources. For these reasons, the performance of …

A Modeling Study Of The History-Dependence Of Conduction Delay In Unmyelinated Axons, Yang Zhang

Dissertations

Conduction delay in an axon is the time required for an action potential to propagate between two positions. It is a function of the axon’s passive membrane properties, voltage-gated ion channels and the Na+/K+ pump, and can be substantially affected by neuromodulators. The conduction delay of action potential, generated by the pyloric dilator (PD) neuron unmyel i nated motor axon in the stomatogastric nervous system, shows significant variability with ongoing bursting or Poisson stimulation. When the axon is stimulated, the mean value (Dmean) and coefficient variation of conduction delay (CV-D) slowly increase with time (slow timescale effect), and the relationship …

Particle Filtering For Frequency Estimation From Acoustic Time-Series In Dispersive Media, Nattapol Aunsri

Dissertations

Acoustic signals propagating in the ocean carry information about geometry and environmental parameters within the propagation medium. Accurately retrieving this information leads us to effectively estimate parameters that are of utmost importance in environmental studies, climate monitoring, and defense. This dissertation focuses on the development of sequential Bayesian filtering methods to obtain accurate estimates of instantaneous frequencies using Short Term Fourier Transforms within the acoustic field measured at an array of hydrophones, which can be used in a subsequent step for the estimation of propagation related parameters. We develop a particle filter to estimate these frequencies along with modal amplitudes, …

Using Structural And Semantic Methodologies To Enhance Biomedical Terminologies, Zhe He

Dissertations

Biomedical terminologies and ontologies underlie various Health Information Systems (HISs), Electronic Health Record (EHR) Systems, Health Information Exchanges (HIEs) and health administrative systems. Moreover, the proliferation of interdisciplinary research efforts in the biomedical field is fueling the need to overcome terminological barriers when integrating knowledge from different fields into a unified research project. Therefore well-developed and well-maintained terminologies are in high demand. Most of the biomedical terminologies are large and complex, which makes it impossible for human experts to manually detect and correct all errors and inconsistencies. Automated and semi-automated Quality Assurance methodologies that focus on areas that are more …

Vehicle Re-Routing Strategies For Congestion Avoidance, Juan Pan

Dissertations

Traffic congestion causes driver frustration and costs billions of dollars annually in lost time and fuel consumption. This dissertation introduces a cost-effective and easily deployable vehicular re-routing system that reduces the effects of traffic congestion. The system collects real-time traffic data from vehicles and road-side sensors, and computes proactive, individually tailored re-routing guidance, which is pushed to vehicles when signs of congestion are observed on their routes. Subsequently, this dissertation proposes and evaluates two classes of re-routing strategies designed to be incorporated into this system, namely, Single Shortest Path strategies and Multiple Shortest Paths Strategies.

These strategies are firstly implemented …

The Winds Of Change: The Political Ecology Of Renewable Energy Transition In Vermont, Jill Mcnulty Clegg

Theses

This research presents a case study of renewable energy transition (RET) in Vermont, illustrated by a recently completed commercial wind project in the Lowell Mountains. Preliminary analysis maps out the current political landscape of Vermont’s RET – its stakeholders, political climate, and important policy advances. Subsequent analysis focuses on the relationship between RET and the unique aspects of Vermont’s institutions, culture, and communities. Important elements of this analysis include the ways that community groups form a vital link between citizens and the State, the unique opportunities and challenges presented by Vermont’s pastoral land perception and activist heritage, and the way …

Innovations In State-Level Solar Energy Policy : Motivating Community Investment In Resiliency, Sarah Katheryn Gentile

Theses

Community-level resilience in the face of climate change is critical for New Jersey. Through a review of current literature, evidence is provided that a majority of work being done with respect to climate-change planning is taking place at the local level. On the basis of case-study analyses, three community renewable energy projects are examined as well as two policy tools that are helping to facilitate development of local capacity to generate renewable energy. The best elements of these initiatives are extracted and form the basis of a policy discussion intended to encourage local level generation of renewable energy, thereby increasing …

Thermochemical Properties Of C3 To C5 Unsaturated Carbonyl Alkenes: Enthalpies Of Formation, Entropy, Heat Capacity, Bond Enthalpy, Ruiqi Jian

Theses

α,β and α-γ unsaturated carbonyl compounds are important classes of carbonyl compounds with the general structure R-(O=C)-Cα=Cβ-R’ and R-(O=Cγ)-Cβ-Cα=Cβ-R’. These compounds are utilized in industry and are also produced as intermediates of hydrocarbon oxidation in chemistry of the atmosphere and in combustion. These unsaturated carbonyls are common environmental pollutants, are frequently associated with adverse effects, and are considered to play an important role in human cancer. Their stability, thermochemical properties are important to understanding their reaction paths in atmospheric, combustion and bio related environments. Enthalpy, entropy, and heat capacity of unsaturated alkene molecules, and radicals corresponding to hydrogen atom …

Mems Approaches In Infrared Imaging, George Papavieros

Theses

The design and performance simulation of a novel Microelectromechanical System (MEMS) based infrared detector, that utilizes coefficient of thermal expansion, is discussed. The detector design uses a variety of thermal expansion coefficient materials, including alloys which are connected to ambient through a thermal conducting bridge. The thermal flux, due to the incident IR photons, is determined by the Extended Blackbody Calculator (BBC). These materials are physically interfaced with different types of piezoelectric resonators, constructed using the MEMS process. The expansion due to heating, applies stress to the piezoelectric resonator material. This thermally induced stress forces the resonator to alter its …

Comparison Of Different Differential Expression Analysis Tools For Rna-Seq Data, Junfei Zhu

Theses

In molecular biology research, RNA-seq is a relatively new method for transcriptome profiling. It utilizes the next generation sequencing technology to provide huge amount information about the variety and abundance of RNA present in an organism of interest at a specific state and a given time. One of the most important tasks of RNA-seq analysis is finding genes that are expressed differently in different subject groups. A lot of differential expression analysis tools for RNA-seq have been developed, but there is no golden standard in this field. In this research, four commonly used tools (DESeq, edgeR, limma, and cuffdiff) are …