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City University of New York (CUNY)

Theses/Dissertations

2018

Articles 31 - 60 of 81

Full-Text Articles in Physical Sciences and Mathematics

Flexible And Versatile Soft Templates For Mesoporous Silicas And Organosilicas Based On Pluronic Block Copolymer Surfactants And Their Mixtures, George Farid Sep 2018

Flexible And Versatile Soft Templates For Mesoporous Silicas And Organosilicas Based On Pluronic Block Copolymer Surfactants And Their Mixtures, George Farid

Dissertations, Theses, and Capstone Projects

In this dissertation, the work will be discussed that was focused on the synthesis of consolidated periodic mesoporous materials such as 2-D hexgonal ordered mesoporous silicas (SBA-15) as well as single-micelle-templated silica and organosilica nanotubes and nanospheres using triblock copolymer surfactants and their mixtures in the presence of a swelling agent. The introductory section, Chapter 1, will address the current state of the tunability of single-micelle-templated silica and organosilica nanotubes and will compare it with the work presented in this dissertation on the use of a dual-surfactant templating systems. Chapter 2 of the dissertation discusses transmission electron microscopy characterization of …


List, Sample, And Count, Ali Assarpour Sep 2018

List, Sample, And Count, Ali Assarpour

Dissertations, Theses, and Capstone Projects

Counting plays a fundamental role in many scientific fields including chemistry, physics, mathematics, and computer science. There are two approaches for counting, the first relies on analytical tools to drive closed form expression, while the second takes advantage of the combinatorial nature of the problem to construct an algorithm whose output is the number of structures. There are many algorithmic techniques for counting, they cover the explicit approach of counting by listing to the approximate approach of counting by sampling.

This thesis looks at counting three sets of objects. First, we consider a subclass of boolean functions that are monotone. …


Synthesis And Evaluation Of Densely-Functionalized Troponoids, Danielle R. Hirsch Sep 2018

Synthesis And Evaluation Of Densely-Functionalized Troponoids, Danielle R. Hirsch

Dissertations, Theses, and Capstone Projects

Herein, we document our efforts to expand the scope of troponoid synthetic methodology towards densely-substituted scaffolds. This body of work has focused primarily on an oxidopyrylium cycloaddition/ring-opening strategy for the synthesis and biochemical evaluation of troponoids for assistance in a variety of medicinal chemistry studies. In Chapter 1, we outline the use of this synthetic strategy in the profiling of a library of synthetic αHTs against an aminoglycoside antibiotic resistance enzyme known as aminoglycoside-2’’-O-nucleotidyltransferase [ANT(2’’)-Ia]. Enzymatic mechanistic insights have been gleaned from an assessment of troponoid/antibiotic synergistic potential. In particular, two synthetic constructs were identified as promising antibiotic adjuvant candidates, …


Private-Key Fully Homomorphic Encryption For Private Classification Of Medical Data, Alexander N. Wood Sep 2018

Private-Key Fully Homomorphic Encryption For Private Classification Of Medical Data, Alexander N. Wood

Dissertations, Theses, and Capstone Projects

A wealth of medical data is inaccessible to researchers and clinicians due to privacy restrictions such as HIPAA. Clinicians would benefit from access to predictive models for diagnosis, such as classification of tumors as malignant or benign, without compromising patients’ privacy. In addition, the medical institutions and companies who own these medical information systems wish to keep their models private when used by outside parties.

Fully homomorphic encryption (FHE) enables practical polynomial computation over encrypted data. This dissertation begins with coverage of speed and security improvements to existing private-key fully homomorphic encryption methods. Next this dissertation presents a protocol for …


Fundamental Chemistry Related To The Separations And Coordination Of Actinium-225, Thorium-227, And Technetium-99, Jasmine L. Hatcher Sep 2018

Fundamental Chemistry Related To The Separations And Coordination Of Actinium-225, Thorium-227, And Technetium-99, Jasmine L. Hatcher

Dissertations, Theses, and Capstone Projects

This work explores the fundamental chemistry of actinium, thorium, and technetium in an effort to develop methodologies which help to address complications specific to each of these elements. Developing fundamental knowledge in inorganic chemistry has the power to meaningfully address a number of real world problems. By using simple systems and experiments like following an electron or changing the solvent system, we are able to gain invaluable information which can be used to address major issues.

Actinium-225 (t½: 9.92 d) is an alpha-emitting radionuclide with nuclear properties well suited for alpha therapy of malignant tumors. The present global …


Building Test Anonymity Networks In A Cybersecurity Lab Environment, John Schriner Aug 2018

Building Test Anonymity Networks In A Cybersecurity Lab Environment, John Schriner

Student Theses

This paper explores current methods for creating test anonymity networks in a laboratory environment for the purpose of improving these networks while protecting user privacy. We first consider how each of these networks is research-driven and interested in helping researchers to conduct their research ethically. We then look to the software currently available for researchers to set up in their labs. Lastly we explore ways in which digital forensics and cybersecurity students could get involved with these projects and look at several class exercises that help students to understand particular attacks on these networks and ways they can help to …


A 3d Characteristics Database Of Land Engraved Areas With Known Subclass, Entni Lin Jun 2018

A 3d Characteristics Database Of Land Engraved Areas With Known Subclass, Entni Lin

Student Theses

Subclass characteristics on bullets may mislead firearm examiners when they rely on traditional 2D images. In order to provide indelible examples for training and help avoid identification errors, 3D topography surface maps and statistical methods of pattern recognition are applied to toolmarks on bullets containing known subclass characteristics. This research was conducted by collecting 3D topography surface map data from land engraved areas of bullets fired through known barrels. This data was processed and used to train the statistical algorithms to predict their origin. The results from the algorithm are compared with the “right answers” (i.e. correct IDs) of the …


An Improved Method For The Analysis Of Fiber Evidence Using Polarized Light Microscopy, Samuel F. Kaplan Jun 2018

An Improved Method For The Analysis Of Fiber Evidence Using Polarized Light Microscopy, Samuel F. Kaplan

Student Theses

Using the basic fundamentals of polarized light microscopy, a new and improved method for identifying synthetic fibers is presented in this thesis. Using the equation of an ellipse in spherical coordinates, an EXCEL™ (Microsoft Inc., Seattle, WA) spreadsheet was developed that generated tables of data that provide a foundation for a new and more efficient method in fiber analysis. Intermediate refractive index values for each subclass of textile fibers were calculated based on the fiber's principal refractive index values. The angles of refractive index matching to known refractive index fluids vary from 0 to 90 degrees upon rotation of the …


Multimodal Depression Detection: An Investigation Of Features And Fusion Techniques For Automated Systems, Michelle Renee Morales May 2018

Multimodal Depression Detection: An Investigation Of Features And Fusion Techniques For Automated Systems, Michelle Renee Morales

Dissertations, Theses, and Capstone Projects

Depression is a serious illness that affects a large portion of the world’s population. Given the large effect it has on society, it is evident that depression is a serious health issue. This thesis evaluates, at length, how technology may aid in assessing depression. We present an in-depth investigation of features and fusion techniques for depression detection systems. We also present OpenMM: a novel tool for multimodal feature extraction. Lastly, we present novel techniques for multimodal fusion. The contributions of this work add considerably to our knowledge of depression detection systems and have the potential to improve future systems by …


Optimization Of Cuinxga1-Xse2 Solar Cells With Post Selenization, Zehra Cevher May 2018

Optimization Of Cuinxga1-Xse2 Solar Cells With Post Selenization, Zehra Cevher

Dissertations, Theses, and Capstone Projects

The chalcopyrite semiconductor CuInxGa1-xSe2 is considered as the most promising material for high efficiency thin film solar cells due to its exceptional radiation stability, tunable direct bandgap, high light absorption coefficient and low cost preparation methods. In this thesis, we present the systematic investigation of the deposition conditions to optimize the CuInxGa1-xSe2 device performance using the two-step deposition method. Further, we utilized nonlinear optical methods to investigate the deposition parameters to optimize the bulk and interface properties of photovoltaic devices.

First, we investigated the deposition parameters to optimize the structural, …


Assessing The Ordinality Of Response Bias With Item Response Models: A Case Study Using The Phq-9, Venessa N. Singhroy May 2018

Assessing The Ordinality Of Response Bias With Item Response Models: A Case Study Using The Phq-9, Venessa N. Singhroy

Dissertations, Theses, and Capstone Projects

Improper scale usage in psychological and clinical assessment is an important problem. If respondents do not use the scales in a consistent manner, the reliability of a composite is likely to be attenuated. This is particularly problematic when particular items are singled out for special treatment or when subscales are of interest, not just a total score. This study used both non-parametric and parametric item response theory (IRT) methods to gain further insight into the validity of the PHQ-9, a dual purpose instrument that assesses the severity of depressive symptoms using nine Likert-scale items and allows the investigator to establish …


Pregnancy Induced Alterations Of Reproductive Tract Collagen And Elastin In A Murine Model, Basant K. Dhital May 2018

Pregnancy Induced Alterations Of Reproductive Tract Collagen And Elastin In A Murine Model, Basant K. Dhital

Dissertations, Theses, and Capstone Projects

This thesis reports on structural and dynamical modifications of reproductive tract elastin and collagen as a function of parity. Pelvic floor dysfunction, including pelvic organ prolapse (POP) is a major concern affecting female health worldwide, leading to surgeries costing billions of dollars annually. Collagen, elastic fibers, and proteoglycans are major extracellular matrix (ECM) components found in connective tissues. Vaginal child birth, advancing age, and disruption or dysfunction of connective tissue are major risk factors of POP. In the female reproductive tract, the assembly of elastic fibers is crucial for the pelvic floor support. Any disturbance in the synthesis, assembly, and …


N-Representability In The Quantum Kernel Energy Method, Walter Polkosnik May 2018

N-Representability In The Quantum Kernel Energy Method, Walter Polkosnik

Dissertations, Theses, and Capstone Projects

The Kernel Energy Method (KEM) delivers accurate full molecule energies using less computational resources than standard ab-initio quantum chemical approaches. KEM achieves this efficiency by decomposing a system of atoms into disjoint subsets called kernels. The results of full ab-initio calculations on each individual single kernel and on each double kernel formed by the union of each pair of single kernels are combined in an equation of a form that is specific to KEM to provide an approximation to the full molecule energy. KEM has been demonstrated to give accurate molecular energies over a wide range of systems, chemical methods …


Standard And Anomalous Wave Transport Inside Random Media, Xujun Ma May 2018

Standard And Anomalous Wave Transport Inside Random Media, Xujun Ma

Dissertations, Theses, and Capstone Projects

This thesis is a study of wave transport inside random media using random matrix theory. Anderson localization plays a central role in wave transport in random media. As a consequence of destructive interference in multiple scattering, the wave function decays exponentially inside random systems. Anderson localization is a wave effect that applies to both classical waves and quantum waves. Random matrix theory has been successfully applied to study the statistical properties of transport and localization of waves. Particularly, the solution of the Dorokhov-Mello-Pereyra-Kumar (DMPK) equation gives the distribution of transmission.

For wave transport in standard one dimensional random systems in …


Re-Architecting Mass Storage Input/Output For Performance And Efficiency, Robert Gezelter May 2018

Re-Architecting Mass Storage Input/Output For Performance And Efficiency, Robert Gezelter

Dissertations, Theses, and Capstone Projects

The semantics and fundamental structure of modern operating system IO systems dates from the mid-1960's to the mid-1970's, a period of time when computing power and memory capacity were a mere fraction of today's systems. Engineering tradeoffs made in the past enshrine the resource availability context of computing at that time. Deconstructing the semantics of the IO infrastructure allows a re-examination of long-standing design decisions in the context of today's greater processing and memory resources. The re-examination allows changes to several wide-spread paradigms to improve efficiency and performance.


Coincidence Of Bargaining Solutions And Rationalizability In Epistemic Games, Todd Stambaugh May 2018

Coincidence Of Bargaining Solutions And Rationalizability In Epistemic Games, Todd Stambaugh

Dissertations, Theses, and Capstone Projects

Chapter 1: In 1950, John Nash proposed the Bargaining Problem, for which a solution is a function that assigns to each space of possible utility assignments a single point in the space, in some sense representing the ’fair’ deal for the agents involved. Nash provided a solution of his own, and several others have been presented since then, including a notable solution by Ehud Kalai and Meir Smorodinsky. In chapter 1, a complete account is given for the conditions under which the two solutions will coincide for two player bargaining scenarios.

Chapter 2: In the same year, Nash …


Divergence Of Cat(0) Cube Complexes And Coxeter Groups, Ivan Levcovitz May 2018

Divergence Of Cat(0) Cube Complexes And Coxeter Groups, Ivan Levcovitz

Dissertations, Theses, and Capstone Projects

We provide geometric conditions on a pair of hyperplanes of a CAT(0) cube complex that imply divergence bounds for the cube complex. As an application, we characterize right-angled Coxeter groups with quadratic divergence and show right-angled Coxeter groups cannot exhibit a divergence function between quadratic and cubic. This generalizes a theorem of Dani-Thomas that addressed the class of 2-dimensional right-angled Coxeter groups. This characterization also has a direct application to the theory of random right-angled Coxeter groups. As another application of the divergence bounds obtained for cube complexes, we provide an inductive graph theoretic criterion on a right-angled Coxeter group's …


The Distribution Of Totally Positive Integers In Totally Real Number Fields, Tianyi Mao May 2018

The Distribution Of Totally Positive Integers In Totally Real Number Fields, Tianyi Mao

Dissertations, Theses, and Capstone Projects

Hecke studies the distribution of fractional parts of quadratic irrationals with Fourier expansion of Dirichlet series. This method is generalized by Behnke and Ash-Friedberg, to study the distribution of the number of totally positive integers of given trace in a general totally real number field of any degree. When the number field is quadratic, Beck also proved a mean value result using the continued fraction expansions of quadratic irrationals. We generalize Beck’s result to higher moments. When the field is cubic, we show that the asymptotic behavior of a weighted Diophantine sum is related to the structure of the unit …


Finding Paths Via Quantum Systems And Its Application For Quantum Algorithms, Daniel S. Koch May 2018

Finding Paths Via Quantum Systems And Its Application For Quantum Algorithms, Daniel S. Koch

Dissertations, Theses, and Capstone Projects

The field of Quantum Information Theory provides the theoretical foundation for the pursuit of quantum computers. The ongoing questions of how quantum computers will be realized and what they will achieve, are both very uncertain. However, worldwide efforts are beginning to converge on some answers, and the future of quantum computers is looking brighter than ever. In contribution to the grand goal that is quantum computing, this thesis serves as a demonstration to the usefulness of quantum over classical computing. The central theme of my work, and my collaborators, is the exploration of using quantum systems as a tool for …


Singlet Oxygen Oxidation Of Guanine, 9-Methylguanine And Guanine-Cytosine Base Pair: Dynamics And Kinetics Revealed By Parallel Gas- And Solution-Phase Experiments And Computations, Wenchao Lu May 2018

Singlet Oxygen Oxidation Of Guanine, 9-Methylguanine And Guanine-Cytosine Base Pair: Dynamics And Kinetics Revealed By Parallel Gas- And Solution-Phase Experiments And Computations, Wenchao Lu

Dissertations, Theses, and Capstone Projects

Singlet oxygen (1O2) oxidatively generated damage of DNA gives rise to mutagenesis, carcinogenesis, and cellular death. Guanine is the most susceptible DNA target of 1O2. The related process has been studied over three decades but the mechanism has remained elusive. My thesis research has focused on reaction mechanism, dynamics and kinetics of 1O2 oxidation of guanine, 9-methylguanine and guanine-cytosine base pair, from the gas-phase bare ions, through hydrated clusters, to aqueous solution. Various techniques have been adapted in the work, including 1O2 generation and detection, guided-ion beam tandem mass …


The Structure Of Models Of Second-Order Set Theories, Kameryn J. Williams May 2018

The Structure Of Models Of Second-Order Set Theories, Kameryn J. Williams

Dissertations, Theses, and Capstone Projects

This dissertation is a contribution to the project of second-order set theory, which has seen a revival in recent years. The approach is to understand second-order set theory by studying the structure of models of second-order set theories. The main results are the following, organized by chapter. First, I investigate the poset of T-realizations of a fixed countable model of ZFC, where T is a reasonable second-order set theory such as GBC or KM, showing that it has a rich structure. In particular, every countable partial order embeds into this structure. Moreover, we can arrange so that these embedding preserve …


On Some Geometry Of Graphs, Zachary S. Mcguirk May 2018

On Some Geometry Of Graphs, Zachary S. Mcguirk

Dissertations, Theses, and Capstone Projects

In this thesis we study the intrinsic geometry of graphs via the constants that appear in discretized partial differential equations associated to those graphs. By studying the behavior of a discretized version of Bochner's inequality for smooth manifolds at the cone point for a cone over the set of vertices of a graph, a lower bound for the internal energy of the underlying graph is obtained. This gives a new lower bound for the size of the first non-trivial eigenvalue of the graph Laplacian in terms of the curvature constant that appears at the cone point and the size of …


The Advection-Diffusion Equation And The Enhanced Dissipation Effect For Flows Generated By Hamiltonians, Michael Kumaresan May 2018

The Advection-Diffusion Equation And The Enhanced Dissipation Effect For Flows Generated By Hamiltonians, Michael Kumaresan

Dissertations, Theses, and Capstone Projects

We study the Cauchy problem for the advection-diffusion equation when the diffusive parameter is vanishingly small. We consider two cases - when the underlying flow is a shear flow, and when the underlying flow is generated by a Hamiltonian. For the former, we examine the problem on a bounded domain in two spatial variables with Dirichlet boundary conditions. After quantizing the system via the Fourier transform in the first spatial variable, we establish the enhanced-dissipation effect for each mode. For the latter, we allow for non-degenerate critical points and represent the orbits by points on a Reeb graph, with vertices …


Geometry And Analysis Of Some Euler-Arnold Equations, Jae Min Lee May 2018

Geometry And Analysis Of Some Euler-Arnold Equations, Jae Min Lee

Dissertations, Theses, and Capstone Projects

In 1966, Arnold showed that the Euler equation for an ideal fluid can arise as the geodesic flow on the group of volume preserving diffeomorphisms with respect to the right invariant kinetic energy metric. This geometric interpretation was rigorously established by Ebin and Marsden in 1970 using infinite dimensional Riemannian geometry and Sobolev space techniques. Many other nonlinear evolution PDEs in mathematical physics turned out to fit in this universal approach, and this opened a vast research on the geometry and analysis of the Euler-Arnold equations, i.e., geodesic equations on a Lie group endowed with one-sided invariant metrics. In this …


Physical Applications Of The Geometric Minimum Action Method, George L. Poppe Jr. May 2018

Physical Applications Of The Geometric Minimum Action Method, George L. Poppe Jr.

Dissertations, Theses, and Capstone Projects

This thesis extends the landscape of rare events problems solved on stochastic systems by means of the \textit{geometric minimum action method} (gMAM). These include partial differential equations (PDEs) such as the real Ginzburg-Landau equation (RGLE), the linear Schroedinger equation, along with various forms of the nonlinear Schroedinger equation (NLSE) including an application towards an ultra-short pulse mode-locked laser system (MLL).

Additionally we develop analytical tools that can be used alongside numerics to validate those solutions. This includes the use of instanton methods in deriving state transitions for the linear Schroedinger equation and the cubic diffusive NLSE.

These analytical solutions are …


Adaptation And Augmentation: Towards Better Rescoring Strategies For Automatic Speech Recognition And Spoken Term Detection, Min Ma May 2018

Adaptation And Augmentation: Towards Better Rescoring Strategies For Automatic Speech Recognition And Spoken Term Detection, Min Ma

Dissertations, Theses, and Capstone Projects

Selecting the best prediction from a set of candidates is an essential problem for many spoken language processing tasks, including automatic speech recognition (ASR) and spoken keyword spotting (KWS). Generally, the selection is determined by a confidence score assigned to each candidate. Calibrating these confidence scores (i.e., rescoring them) could make better selections and improve the system performance. This dissertation focuses on using tailored language models to rescore ASR hypotheses as well as keyword search results for ASR-based KWS.

This dissertation introduces three kinds of rescoring techniques: (1) Freezing most model parameters while fine-tuning the output layer in order to …


Heat Stress Vulnerability: Analyzing The Socio-Environmental Factors Influencing Heat Stress Hospital Visits And Implementation Of Green Infrastructure In New York City, Jose Pillich May 2018

Heat Stress Vulnerability: Analyzing The Socio-Environmental Factors Influencing Heat Stress Hospital Visits And Implementation Of Green Infrastructure In New York City, Jose Pillich

Dissertations, Theses, and Capstone Projects

The goal of this study was to identify factors leading to heat stress hospitalizations visits in New York City through the use of climatological and social science data, thus enabling greater targeting of individuals and groups with heightened vulnerability to extreme heat. Recent research has established that climate change will increase overall temperatures in New York City in the future. Heat waves are predicted to increase in frequency and severity, adversely impacting public health and increasing heat vulnerability that could lead to heat stroke or other comorbidities. This dissertation takes into account existing data to generate a new model that …


Parp Pet Imaging Agents, Brandon Carney Feb 2018

Parp Pet Imaging Agents, Brandon Carney

Dissertations, Theses, and Capstone Projects

The poly (adenosine-diphosphate (ADP) ribose) polymerase (PARP) family of enzymes has been of interest to researchers and clinicians for over fifty years, especially the first member of the family, PARP1. This enzyme has become a target for cancer therapeutics due the reliance of highly proliferating cells on PARP1 for genomic maintenance. In the coming age of individualized medicine, however, highly specific therapeutic agents like PARP inhibitors are in need of similarly highly specific companion diagnostic agents. These kind of agents have been made possible with the quickly progressing field of molecular imaging. Specifically, positron emission tomography (PET) has enabled the …


Infinitely Many Solutions To Asymmetric, Polyharmonic Dirichlet Problems, Edger Sterjo Feb 2018

Infinitely Many Solutions To Asymmetric, Polyharmonic Dirichlet Problems, Edger Sterjo

Dissertations, Theses, and Capstone Projects

In this dissertation we prove new results on the existence of infinitely many solutions to nonlinear partial differential equations that are perturbed from symmetry. Our main theorems focus on polyharmonic Dirichlet problems with exponential nonlinearities, and are now published in Topol. Methods Nonlinear Anal. Vol. 50, No.1, (2017), 27-63. In chapter 1 we give an introduction to the problem, its history, and the perturbation argument itself. In chapter 2 we prove the variational principle of Bolle on the behavior of critical values under perturbation, and the variational principle of Tanaka on the existence of critical points of large augmented Morse …


Relating Justification Logic Modality And Type Theory In Curry–Howard Fashion, Konstantinos Pouliasis Feb 2018

Relating Justification Logic Modality And Type Theory In Curry–Howard Fashion, Konstantinos Pouliasis

Dissertations, Theses, and Capstone Projects

This dissertation is a work in the intersection of Justification Logic and Curry--Howard Isomorphism. Justification logic is an umbrella of modal logics of knowledge with explicit evidence. Justification logics have been used to tackle traditional problems in proof theory (in relation to Godel's provability) and philosophy (Gettier examples, Russel's barn paradox). The Curry--Howard Isomorphism or proofs-as-programs is an understanding of logic that places logical studies in conjunction with type theory and -- in current developments -- category theory. The point being that understanding a system as a logic, a typed calculus and, a language of a class of categories constitutes …