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Full-Text Articles in Physical Sciences and Mathematics

Macro - And Microstructure Evaluation And Field Applications Of Concrete With Recycled Glass Pozzolan, Marija Krstic Jan 2020

Macro - And Microstructure Evaluation And Field Applications Of Concrete With Recycled Glass Pozzolan, Marija Krstic

Dissertations and Theses

Concrete is the most used material in the world, second only to water. Conventional concrete is produced with Portland cement (PC). The production of cement is an energy intensive operation that has raised significant environmental concerns, since one ton of cement generates an equal ton of CO2. In the USA about 90 million tons of cement are used annually, with 3 million tons used in New York. Most contemporary concrete applications for buildings and infrastructure use high-performance concrete (HPC) mixtures which are produced by replacing a percentage of cement with supplementary cementitious materials (SCMs), consisting mainly of fly-ash …


Tropical Cyclone Hazards In Relation To Propagation Speed, Jiehao Huang Jan 2020

Tropical Cyclone Hazards In Relation To Propagation Speed, Jiehao Huang

Dissertations and Theses

As the population and infrastructure along the US East Coast increase, it becomes increasingly important to study the characteristics of tropical cyclones that can impact the coast. A recent study shows that the propagation speed of tropical cyclones has slowed over the past 60 years, which can lead to greater accumulation of precipitation and greater storm surge impacts. The study presented herein is meant to examine and analyze the relationships that exist between the propagation speed of tropical cyclones, their surface wind strength, displacement angles, and cyclone averaged winds. This analysis is focused on tropical cyclones spanning from 1950-2015 in …


Safe Automated Refactoring For Intelligent Parallelization Of Java 8 Streams, Raffi T. Khatchadourian, Yiming Tang, Mehdi Bagherzadeh Jan 2020

Safe Automated Refactoring For Intelligent Parallelization Of Java 8 Streams, Raffi T. Khatchadourian, Yiming Tang, Mehdi Bagherzadeh

Publications and Research

Streaming APIs are becoming more pervasive in mainstream Object-Oriented programming languages and platforms. For example, the Stream API introduced in Java 8 allows for functional-like, MapReduce-style operations in processing both finite, e.g., collections, and infinite data structures. However, using this API efficiently involves subtle considerations such as determining when it is best for stream operations to run in parallel, when running operations in parallel can be less efficient, and when it is safe to run in parallel due to possible lambda expression side-effects. ics-preserving fashion. The approach, based on a novel data ordering and typestate analysis, consists of preconditions and …


Ftir Analysis Of Bacteria Biomass-Mineral Interactions In Soils, Finola Fung-Khee Jan 2020

Ftir Analysis Of Bacteria Biomass-Mineral Interactions In Soils, Finola Fung-Khee

Dissertations and Theses

Soil organic carbon (SOC) accounts for 70% of the carbon on Earth. It is therefore a key player in global carbon cycling and climate change (Smith et al., 2008). Soil organic matter (SOM) is an important component of organic matter in soils (SOC), and results from biogeochemical process involving net primary producers, soil biomass and soil mineralogy (Horwath and Kuzyakov, 2018). In this study, the interplay between soil bacterial biomass and reactive clay minerals in soils was investigated. The purpose of the research was to shed light into the stabilization of SOC in a bacterial biomass-soil/clay matrix. Soils characterized as …


Multimodal Data Integration For Real-Time Indoor Navigation Using A Smartphone, Yaohua Chang Jan 2020

Multimodal Data Integration For Real-Time Indoor Navigation Using A Smartphone, Yaohua Chang

Dissertations and Theses

We propose an integrated solution of indoor navigation using a smartphone, especially for assisting people with special needs, such as the blind and visually impaired (BVI) individuals. The system consists of three components: hybrid modeling, real-time navigation, and client-server architecture. In the hybrid modeling component, the hybrid model of a building is created region by region and is organized in a graph structure with nodes as destinations and landmarks, and edges as traversal paths between nodes. A Wi-Fi/cellular-data connectivity map, a beacon signal strength map, a 3D visual model (with destinations and landmarks annotated) are collected while a modeler walks …


Edge Device Speaker Verification, Thomas P. Duffy Jan 2020

Edge Device Speaker Verification, Thomas P. Duffy

Dissertations and Theses

The continued shrinking of processors and other physical hardware in concert with development of embeddable machine learning frameworks has enabled new use cases placing machine learning directly in the “wild”. The problem of speaker verification, for a long time, has been deployed to perform inference on systems with significant computations resources. More recently, these systems have been built for smaller, cheaper devices which can be placed in people's homes or other edge locations. Here, we aim to demonstrate that a reasonably accurate, generalizable, text-independent speaker verification system can be built, trained, and, ultimately, deployed onto a microcontroller with as a …


Toward Closing The Urban Surface Energy Balance Using Satellite Remote Sensing, Joshua Hrisko Jan 2020

Toward Closing The Urban Surface Energy Balance Using Satellite Remote Sensing, Joshua Hrisko

Dissertations and Theses

The energy exchanges at the Earth’s surface are responsible for many of the processes that govern weather, climate, human health, and energy use. This exchange, commonly known as the surface energy balance (SEB), determines the near-surface thermodynamic state by partitioning the available energy into surface fluxes. The net all-wave radiation is often the primary energy source, while the heat storage and sensible and latent heat fluxes account for the majority of energy distributed elsewhere. While the SEB of various natural environments(trees, crops, soils) has been well-observed and modeled, the urban surface energy balance remains elusive. This is due to the …


Adapting To Extreme Heat: Social, Atmospheric, And Infrastructure Impacts Of Air Conditioning In Megacities - The Case Of New York City, Harold Gamarro Jan 2020

Adapting To Extreme Heat: Social, Atmospheric, And Infrastructure Impacts Of Air Conditioning In Megacities - The Case Of New York City, Harold Gamarro

Dissertations and Theses

Extreme heat events are becoming more frequent and intense in most large cities. Built-up surfaces also limit cooling mechanisms, leading to warmer conditions in cities, a phenomenon called the Urban Heat Island (UHI). This presents major challenges to reduce adverse health effects of hot weather, particularly in vulnerable populations like the elderly and low-income communities. Here we explore the overall impacts of increasing air conditioning (AC) system adoption in residences as an adaptive measure to reduce human health risks under heat waves, with New York City (NYC) as a case study. This study uses AC adoption data from the 2017 …


Technological Challenges And Innovations In Cybersecurity And Networking Technology Program, Syed R. Zaidi, Ajaz Sana, Aparicio Carranza Jan 2020

Technological Challenges And Innovations In Cybersecurity And Networking Technology Program, Syed R. Zaidi, Ajaz Sana, Aparicio Carranza

Publications and Research

This era is posing a unique challenge to the Cybersecurity and related Engineering Technology areas, stimulated by the multifaceted technological boom expressed in accelerated globalization, digital transformation, the cloud, mobile access apps, and the Internet of Things (IoT)—where more and more devices are connected to the Internet every day. As the use of new Internet-based technologies increase; so does the risk of theft and misuse of sensitive information. This demands the awareness of cyber-criminality and the need for cyber hygiene in corporations, small businesses, and the government. As the need for experienced cybersecurity specialists has skyrocketed in recent years and …


The Tsukano Conjectures On Exponential Sums, Brad Isaacson Jan 2020

The Tsukano Conjectures On Exponential Sums, Brad Isaacson

Publications and Research

We prove three conjectures of Tsukano about exponential sums stated in his Master’s thesis written at Osaka University. These conjectures are variations of earlier conjectures made by Lee and Weintraub which were first proved by Ibukiyama and Saito.


Mode Discrimination In Dissipatively Coupled Laser Arrays, Jiajie Ding, Mohammad-Ali Miri Jan 2020

Mode Discrimination In Dissipatively Coupled Laser Arrays, Jiajie Ding, Mohammad-Ali Miri

Publications and Research

No abstract provided.


Triflic Acid Mediated Sequential Cyclization Of Ortho-Alkynylarylesters With Ammonium Acetate, Maciej E. Domaradzki, Xiaochen Liu, Jiye Ong, Gyeongah Yu, Gan Zhang, Ariel Simantov, Eliyahu Perl, Yu Chen Jan 2020

Triflic Acid Mediated Sequential Cyclization Of Ortho-Alkynylarylesters With Ammonium Acetate, Maciej E. Domaradzki, Xiaochen Liu, Jiye Ong, Gyeongah Yu, Gan Zhang, Ariel Simantov, Eliyahu Perl, Yu Chen

Publications and Research

A triflic acid (TfOH) mediated sequential cyclization of ortho-alkynylarylesters and ammonium acetate (NH4OAc) was reported. The reaction took place via a Brønsted acid-mediated intramolecular cyclization of ortho-alkynylarylesters followed by an ammonium acetate participated substitution reaction, forming isoquinolin-1-ones as the major products. Different from most of the known synthetic methods of isoquinolin-1-ones, no metal catalyst was required in the reported reaction. The regioisomers – isoindolin-1-ones were obtained together with isoquinolin-1-ones in a few cases. The intermediate compounds – isochromen-1-ones and isobenzofuran-1-ones were also isolated. The interconversion experiments showed that the regioisomers formed during the Brønsted acid induced …


Microspheres With Atomic-Scale Tolerances Generate Hyperdegeneracy, Jacob Kher-Alden, Shai Maayani, Leopoldo L. Martin, Mark Douvidzon, Lev Deych, Tal Carmon Jan 2020

Microspheres With Atomic-Scale Tolerances Generate Hyperdegeneracy, Jacob Kher-Alden, Shai Maayani, Leopoldo L. Martin, Mark Douvidzon, Lev Deych, Tal Carmon

Publications and Research

Degeneracies play a crucial rule in precise scientific measurements as well as in sensing applications. Spherical resonators have a high degree of degeneracy thanks to their highest symmetry; yet, fabricating perfect spheres is challenging because even a stem to hold the sphere breaks the symmetry. Here we fabricate a levitating spherical resonator that is evanescently coupled to a standard optical fiber. We characterize the resonators to exhibit an optical quality factor exceeding a billion, 10 μm radius, and sphericity to within less than 1µ. Using our high quality and sphericity, we experimentally lift degeneracies of orders higher than 200, which …


Sugar-Derived Oleogels In Cosmetics And Food Applications: A Case Study Of Trehalose- And Mannitol-Based Gelators, Polina Tsupko Jan 2020

Sugar-Derived Oleogels In Cosmetics And Food Applications: A Case Study Of Trehalose- And Mannitol-Based Gelators, Polina Tsupko

Dissertations and Theses

Gels represent an indispensable part of our everyday lives with direct applications in food, medicine, cosmetics and other industries. Amphiphilic molecules have been shown to act as low molecular weight gelators (LMWGs) and are becoming the main focus of several research groups. Their ability to self-assemble into various morphologies from micelles to bilayer sheets, and remain stable due to noncovalent forces responsible for the formation of the 3D network—Self-Assembled Fibrillar Network (SAFiNs)—is in the core of their ability to produce molecular gels. Those amphiphilic molecules capable of adsorbing at the interface and behaving as surface active agents are known as …


Singlet Fission In A Hexacene Dimer: Energetics Dictate Dynamics, Samuel N. Sanders, Elango Kumarasamy, Kealan J. Fallon, Matthew Y. Sfeir, Luis M. Campos Jan 2020

Singlet Fission In A Hexacene Dimer: Energetics Dictate Dynamics, Samuel N. Sanders, Elango Kumarasamy, Kealan J. Fallon, Matthew Y. Sfeir, Luis M. Campos

Publications and Research

Singlet fission (SF) is an exciton multiplication process with the potential to raise the efficiency limit of single junction solar cells from 33% to up to 45%. Most chromophores generally undergo SF as solid-state crystals. However, when such molecules are covalently coupled, the dimers can be used as model systems to study fundamental photophysical dynamics where a singlet exciton splits into two triplet excitons within individual molecules. Here we report the synthesis and photophysical characterization of singlet fission of a hexacene dimer. Comparing the hexacene dimer to analogous tetracene and pentacene dimers reveals that excess exoergicity slows down singlet fission, …


On The Classification Of Duality Webs For Graded Quivers, Sebastían Franco, Azeem Hasan, Xingyang Yu Jan 2020

On The Classification Of Duality Webs For Graded Quivers, Sebastían Franco, Azeem Hasan, Xingyang Yu

Publications and Research

We study the m-graded quiver theories associated to CY (m+2)-folds and their order (m + 1) dualities. We investigate how monodromies give rise to mutation invariants, which in turn can be formulated as Diophantine equations characterizing the space of dual theories associated to a given geometry. We discuss these ideas in general and illustrate them in the case of orbifold theories. Interestingly, we observe that even in this simple context the corresponding Diophantine equations may admit an infinite number of seeds for m ≥ 2, which translates into an infinite number of disconnected duality webs. Finally, …


"Lagrangian Disks" In M-Theory, Sebastián Franco, Sergei Gukov, Sangmin Lee, Rak-Kyeong Seong, James Sparks Jan 2020

"Lagrangian Disks" In M-Theory, Sebastián Franco, Sergei Gukov, Sangmin Lee, Rak-Kyeong Seong, James Sparks

Publications and Research

While the study of bordered (pseudo-)holomorphic curves with boundary on Lagrangian submanifolds has a long history, a similar problem that involves (special) Lagrangian submanifolds with boundary on complex surfaces appears to be largely overlooked in both physics and math literature. We relate this problem to geometry of coassociative submanifolds in G2 holonomy spaces and to Spin(7) metrics on 8-manifolds with T2 fibrations. As an application to physics, we propose a large class of brane models in type IIA string theory that generalize brane brick models on the one hand and 2d theories T[M4] on …


Dark-Binding Process Relevant To Preventing Photosensitized Oxidation: Conformation-Dependent Light And Dark Mechanisms By A Dual-Functioning Diketone, Sarah J. Belh, Niluksha Walalawela, Stas Lekhtman, Alexander Greer Dec 2019

Dark-Binding Process Relevant To Preventing Photosensitized Oxidation: Conformation-Dependent Light And Dark Mechanisms By A Dual-Functioning Diketone, Sarah J. Belh, Niluksha Walalawela, Stas Lekhtman, Alexander Greer

Publications and Research

Few photosensitizers function in both light and dark processes as they usually have no function when the lights are turned off. We hypothesized that light and dark mechanisms in an α-diketone will be decoupled by dihedral rotation in a conformation- dependent binding process. Successful decoupling of these two functions is now shown. Namely, anti- and syn-skewed conformations of 4,4′-dimethylbenzil promote photosensitized alkoxy radical production, whereas the syn conformation promotes a binding shutoff reaction with trimethyl phosphite. Less rotation of the diketone is better suited to the photosensitizing function since phosphite binding arises through the syn conformer of lower stability. The …


“Treat Me Covalently” – New Tools To Improve Covalent Drug Design For Advancement Of Cancer Treatments, Yuliya Mazo Dec 2019

“Treat Me Covalently” – New Tools To Improve Covalent Drug Design For Advancement Of Cancer Treatments, Yuliya Mazo

Student Theses and Dissertations

The goal of this project was to investigate the complex mechanism of covalent bonding among different molecules and their targets in a modeling software ICM-Pro. Specifically, it included the identification of fundamental aspects of a covalent bonding mechanism of the Michael addition reaction. Michael addition reaction of electrophilic α, β-unsaturated carbonyl compounds with a nucleophilic cysteine residue in thymidylate synthase, papain, and EGFR tyrosine kinase were examined. Thymidylate synthase and EGFR were chosen because they are important targets in the treatment of various types of cancer. In order to find the most optimal parameters, identification and assessment of the effect …


The Rockaway Project - Townes, Diara Jepris D. Townes Dec 2019

The Rockaway Project - Townes, Diara Jepris D. Townes

Capstones

The Rockaway Project is a story-driven website that provides information on the government response to Superstorm Sandy recovery on the Rockaway peninsula in Queens, New York. Dozens of climate resiliency projects have been delayed or remain unfinished, despite millions of dollars in funding and six years of promises. The website hosts audio, visual and digital content, gathered through interviews and data collection.

Link to capstone project: https://www.youtube.com/watch?v=fAq2BeR4bS0&t=1s


Building Mof Nanocomposites With Oxidized Graphitic Carbon Nitride Nanospheres: The Effect Of Framework Geometry On The Structural Heterogeneity, Dimitrios A. Giannakoudakis, Teresa J. Bandosz Dec 2019

Building Mof Nanocomposites With Oxidized Graphitic Carbon Nitride Nanospheres: The Effect Of Framework Geometry On The Structural Heterogeneity, Dimitrios A. Giannakoudakis, Teresa J. Bandosz

Publications and Research

Composite of two MOFs, copper-based Cu-BTC (HKUST-1) and zirconium-based Zr-BDC (UiO-66), with oxidized graphitic carbon nitride nanospheres were synthesized. For comparison, pure MOFs were also obtained. The surface features were analyzed using x-ray diffraction (XRD), sorption of nitrogen, thermal analysis, and scanning electron microscopy (SEM). The incorporation of oxidized g-C3N4 to the Cu-BTC framework caused the formation of a heterogeneous material of a hierarchical pores structure, but a decreased surface area when compared to that of the parent MOF. In the case of UiO-66, functionalized nanospheres were acting as seeds around which the crystals grew. Even though the MOF phases …


Determinism Of Stochastic Processes Through The Relationship Between The Heat Equation And Random Walks, Gurmehar Singh Makker Dec 2019

Determinism Of Stochastic Processes Through The Relationship Between The Heat Equation And Random Walks, Gurmehar Singh Makker

Publications and Research

We study the deterministic characteristics of stochastic processes through investigation of random walks and the heat equation. The relationship is confirmed by discretizing the heat equation in time and space and determining the probability distribution function for random walks in dimension d = 1, 2. The existence of the relationship is presented both through theoretical analysis and numerical computation.


The Privacy Preserving Framework With Virtual Ring And Identity-Based Cryptography For Smart Grid, Leonard Sutanto Dec 2019

The Privacy Preserving Framework With Virtual Ring And Identity-Based Cryptography For Smart Grid, Leonard Sutanto

Publications and Research

One of the main challenges in the smart grid is how to efficiently manage the high-volume data from smart meters and sensors and preserve the privacy from the consumption data to avoid potential attacks (e.g., identity theft) for the involved prosumers, retail electricity providers and other clusters of distributed energy resources. This poster proposes a two-layer framework with the cloud computing infrastructure. The virtual ring and identity-based cryptography are utilized in each layer to preserve privacy efficiently. The methods of the virtual ring and identity-based cryptography are introduced. The purposes and needs are discussed at the end of this poster.


An Application Of The Ising Model, Juliano A. Everett Dec 2019

An Application Of The Ising Model, Juliano A. Everett

Publications and Research

Understanding how the Ising model works,what it represents, and how it can be applied to neurology. Given that an Ising model is an Entropy model that could be representative of the firing of neurons, some assumptions of the system are made and then the process is simulated through Monte Carlo methods.


Static Solid Relaxation Ordered Spectroscopy: Ss-Rosy, Gregory S. Boutis, Ravinath Kausik Nov 2019

Static Solid Relaxation Ordered Spectroscopy: Ss-Rosy, Gregory S. Boutis, Ravinath Kausik

Publications and Research

A two-dimensional pulse sequence is introduced for correlating nuclear magnetic resonance anisotropic chemical shifts to a relaxation time (e.g., T1) in solids under static conditions. The sequence begins with a preparatory stage for measuring relaxation times, and is followed by a multiple pulse sequence for homonuclear dipolar decoupling. Data analysis involves the use of Fourier transform, followed by a one-dimensional inverse Laplace transform for each frequency index. Experimental results acquired on solid samples demonstrate the general approach, and additional variations involving heteronuclear decoupling and magic angle spinning are discussed.


Graded Quivers, Generalized Dimer Models And Toric Geometry, Sebastián Franco, Azeem Hasan Nov 2019

Graded Quivers, Generalized Dimer Models And Toric Geometry, Sebastián Franco, Azeem Hasan

Publications and Research

The open string sector of the topological B-model on CY (m+2)-folds is described by m-graded quivers with superpotentials. This correspondence extends to general m the well known connection between CY (m+2)-folds and gauge theories on the world-volume of D(5-2m)-branes for m = 0, ..., 3. We introduce m-dimers, which fully encode the m-graded quivers and their superpotentials, in the case in which the CY (m+2)-folds are toric. Generalizing the well known m = 1,2 cases, m-dimers significantly simplify the connection between geometry and m-graded quivers. A key …


A Note On Graphs With Prescribed Orbit Structure, Abbe Mowshowitz, Matthias Dehmer, Frank Emmert-Streib Nov 2019

A Note On Graphs With Prescribed Orbit Structure, Abbe Mowshowitz, Matthias Dehmer, Frank Emmert-Streib

Publications and Research

No abstract provided.


Residential Household Yard Care Practices Along Urban-Exurban Gradients In Six Climatically-Diverse U.S. Metropolitan Areas, Dexter H. Locke, Colin Polsky, J. Morgan Grove, Peter M. Groffman, Kristen C. Nelson, Kelli L. Larson, Jeannine Cavender-Bares, James B. Heffernan, Rinku Roy Chowdhury, Sarah E. Hobbie, Neil D. Bettez, Sharon J. Hall, Christopher Neill, Laura Ogden, Jarlath O'Neil-Dunne Nov 2019

Residential Household Yard Care Practices Along Urban-Exurban Gradients In Six Climatically-Diverse U.S. Metropolitan Areas, Dexter H. Locke, Colin Polsky, J. Morgan Grove, Peter M. Groffman, Kristen C. Nelson, Kelli L. Larson, Jeannine Cavender-Bares, James B. Heffernan, Rinku Roy Chowdhury, Sarah E. Hobbie, Neil D. Bettez, Sharon J. Hall, Christopher Neill, Laura Ogden, Jarlath O'Neil-Dunne

Publications and Research

Residential land is expanding in the United States, and lawn now covers more area than the country’s leading irrigated crop by area. Given that lawns are widespread across diverse climatic regions and there is rising concern about the environmental impacts associated with their management, there is a clear need to understand the geographic variation, drivers, and outcomes of common yard care practices. We hypothesized that 1) income, age, and the number of neighbors known by name will be positively associated with the odds of having irrigated, fertilized, or applied pesticides in the last year, 2) irrigation, fertilization, and pesticide application …


Land Surface Temperature Variability Across India: A Remote Sensing Satellite Perspective, Satya Prakash, Hamidreza Norouzi Nov 2019

Land Surface Temperature Variability Across India: A Remote Sensing Satellite Perspective, Satya Prakash, Hamidreza Norouzi

Publications and Research

Land surface temperature (LST) plays a key role in the surface energy budget computation and land surface process studies. The Moderate Resolution Imaging Spectroradiometer (MODIS) sensors onboard the Aqua and Terra satellites provide comprehensive global LST estimates at a fine spatial resolution. The MODIS products were recently upgraded to Collection 6, and shown to be more accurate than its predecessor Collection 5 products. In this study, LST and its variability have been examined across India from Collection 6 of the Aqua MODIS data at 0.05° spatial resolution for the period of 2003 to 2017. All-India mean LST characteristics show distinctive …


Planck's And Callendar's Blackbody Radiation Formulas And Their Fitness To Experimental Data, Max Tran Nov 2019

Planck's And Callendar's Blackbody Radiation Formulas And Their Fitness To Experimental Data, Max Tran

Publications and Research

In this paper, we compare the blackbody radiation density formula obtained with classical physics by Hugh L Callendar and the formula obtained by Max Planck using quantization of energy. We use R and Maxima to analyze their fitness on coordinating experimental data and indicate some limitations with experiments in this area.