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Optically Transparent Microwave Absorber Based On Water-Based Moth-Eye Structures, H Kwon, G D’Aguanno, Andrea Alù

Advanced Science Research Center

We propose an approach to realize an optically transparent microwave absorber based on water-based moth-eye metamaterial structures. The absorber is made of a periodic array of properly shaped glass caps infiltrated with distilled water. Analytical calculations and numerical simulations show that the water-based metamaterial absorbs electromagnetic waves over a wide spectral band ranging from 4GHz to well above 120GHz, showing absorption levels close to 100% for incident radiation that ranges from normal to grazing angles, for both TE and TM polarizations. Yet, the structure is optically transparent, offering exciting opportunities in a variety of civil and military applications, such as …

Authentic Stem Research, Practices Of Science, And Interest Development In An Informal Science Education Program, Bobby Habig, Preeti Gupta

Publications and Research

Background: Two critical challenges in science education are how to engage students in the practices of science and how to develop and sustain interest. The goal of this study was to examine the extent to which high school youth, the majority of whom are members of racial and ethnic groups historically underrepresented in STEM, learn the skills and practices of science and in turn develop interest in conducting scientific research as part of their career pursuits. To accomplish this goal, we applied Hidi and Renninger’s well-tested theoretical framework for studying interest development in the context of a museum-based, informal science …

Exclusion Statistics For Particles With A Discrete Spectrum, Stéphane Ouvry, Alexios P. Polychronakos

Publications and Research

We formulate and study the microscopic statistical mechanics of systems of particles with exclusion statistics in a discrete one-body spectrum. The statistical mechanics of these systems can be expressed in terms of effective single-level grand partition functions obeying a generalization of the standard thermodynamic exclusion statistics equation of state. We derive explicit expressions for the thermodynamic potential in terms of microscopic cluster coefficients and show that the mean occupation numbers of levels satisfy a nesting relation involving a number of adjacent levels determined by the exclusion parameter. We apply the formalism to the harmonic Calogero model and point out a …

Color Charge Correlations In The Proton At Nlo: Beyond Geometry Based Intuition, Adrian Dumitru, Heikki Mäntysaari, Risto Paatelainen

Publications and Research

Color charge correlators provide fundamental information about the proton structure. In this Letter, we evaluate numerically two-point color charge correlations in a proton on the light cone including the next-to-leading order corrections due to emission or exchange of a perturbative gluon. The non-perturbative valence quark structure of the proton is modelled in a way consistent with high-x proton structure data. Our results show that the correlator exhibits startlingly non-trivial behavior at large momentum transfer or central impact parameters, and that the color charge correlation depends not only on the impact parameter but also on the relative transverse momentum of …

Wavefront-Selective Fano Resonant Metasurface, Adam C. Overvig, Andrea Alù

Publications and Research

Fano resonances are conventionally understood as sharp spectral features with selectivity in the momentum-frequency domain, implying that they can be excited only by plane waves with specific frequencies and incident angles. We demonstrate that Fano resonances can be made generally selective in the space-frequency domain. They can be tailored to resonate only when excited by a frequency, polarization, and wavefront of choice. This generalization reveals that Fano systems are characterized by eigenwaves that scatter to their time-reversed image upon reflection. Although in conventional Fano systems this trivially occurs for normally incident plane waves, we show that, in general, the selected …

Calabi-Yau Products: Graded Quivers For General Toric Calabi-Yaus, 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 generalizes the connection between CY (m + 2)-folds and gauge theories on the worldvolume of D(5 − 2m)-branes for m = 0, . . . , 3 to arbitrary m. In this paper we introduce the Calabi-Yau product, a new algorithm that starting from the known quiver theories for a pair of toric CY_m+2 and CY_n+2 produces the quiver theory for a related CY_{m+n+3 …}

Jazz Colors: Pigment Identification In The Gouaches Used By Henri Matisse, Ana Martins, Anne Catherine Prud’Hom, Maroussia Duranton, Abed Haddad, Celine Daher, Anne Genachte-Le Bail, Tiffany Tang

Publications and Research

Jazz, the illustrated book by Henri Matisse, is a testament to the vitality of the artist in the last decade of his career. The book consists of twenty illustrations reproduced in 370 copies using a stencil-based printing technique and the same Linel gouaches the artist had used for the original maquettes. This study reports on the comprehensive analysis carried out to identify the pigments in the gouaches used in Jazz by transmitted and reflectance infrared, Raman, SERS, and X-ray fluorescence spectroscopies, and describes the lightfastness of these gouaches as evaluated by microfaedometry. This study also highlights the necessity of …

The Interface And Instrumentality Of Eurorack Modular Synthesis, Eliot Bates

Publications and Research

In this essay, I will examine a couple of aspects of hardware modular synthesizers which, despite not being a “new” morphological form (most commercially sold synthesizers from the 1960s through the early 1970s were modular), experienced an extremely unlikely expansion of interest and activity in the mid-1990s. With a contemporary modular synth, users buy a powered rack that holds modules specific to one of several competing formats. For the two most widely adopted formats, Eurorack (sometimes called 3U in reference to the height of modules, or Doepfer A-100 after the first branded system to adopt this panel height) and MOTM/MU …

Geol 746: Groundwater Hydrology, Tim Eaton

Open Educational Resources

No abstract provided.

Deployment Of Causal Effect Estimation In Live Games Of Dota 2, Anders Harboell Christiansen, Emil Gensby, Bryan S. Weber

Publications and Research

In this paper, we provide an application that produces consistent in-game estimates of win probabilities in Dota 2. Previous work shows that common methods of identifying the effect of in-game features are strongly inconsistent, which we corroborate here with a large data set. We further provide an in-game application for players to see these estimates during the game as a training tool, along with displaying the estimated marginal impact of the primary actions (kills, last hits, and tower damage), which are previously known only by intuition. In a double-blind setting, we are the first to identify that users observe a …

Long Term Nutrient And Chlorophyll A Dynamics Across Long Island Sound And Impacts On Dissolved Oxygen Conditions Within The Western Sound (1991-2019), Sherry Perreira

Dissertations and Theses

Nitrogen overload, eutrophication, and hypoxia have been challenging and persistent water quality problems in Long Island Sound (LIS) over the past decades with major impacts on commercial industries, ecology, and recreational activities in the region. Recognizing these problems, the EPA enforced three phases of the Clean Water Act (CWA) to reduce nitrogen loads in an effort to improve this important estuary. This study examines how nitrogen (NH₃, NO_x & TDN), chlorophyll a (CHLA), and dissolved oxygen (DO) concentrations changed in LIS over the past 30 years, in response to water quality regulations as well as changes in …

On The Improvements Of Boundary-Layer Representation For High Resolution Weather Forecasting In Costal-Urban Environments, David Melecio-Vazquez

Dissertations and Theses

As large urban centers around the world become more densely populated, the global conversion from natural to man-made land surfaces will only increase. These land-use changes affect the urban surface energy budget which in turn changes the structure of the planetary boundary layer (PBL) above. With current high-performance computing systems, meteorological and built environment information can be better utilized to quantify the anthropogenic effects of these modifications. Although these systems have improved forecasting near-surface weather conditions, a comprehensive approach to represent urban impacts on the PBL is still limited. Improved PBL representation can lead to better weather and climate forecasts, …

Effects Of Flow Rate And Droplet Size On Double Emulsion Morphology, Rossana Iturbide

Dissertations and Theses

Experimental work has been conducted to analyze the interactions and morphology of three fluids, an air bubble and oil droplet in water. The experimental results have been compared to a morphology diagram based on the spreading factors that depend on the interfacial tension between two fluids. The possible morphologies are complete engulfment, partial engulfment, and no coalescence. The experimental study utilized an acrylic tube filled with water where an air bubble and oil droplet were injected and forced to interact after injection. Following the surface tension and interfacial tension measurements of mineral oil, silicone oil, olive oil, water, and air, …

Polarization Sensitive Imaging Techniques Using Quantum Entangled Qubits, Vitaly Sukharenko

Dissertations and Theses

The aim of this research is to study imaging techniques using quantum entangled qubits. These techniques extract information about the quantum state of two entangled qubits and corelate the degree of entanglement to each pixel. Imaging information of the underlying structure or material is decoded using the reconstruction of the quantum density matrix along with the calculated entanglement and concurrence levels between the two qubits. Reconstruction of a quantum state and quantum state tomography are of increasing importance in quantum information science. Quantum state tomography is used to describe entanglement of trapped ions [1] and photons [2]. Number of experiments …

Spatial And Non-Spatial Patterns Of Genetic Diversity In Neotropical Bats, Andrea J. Calderon Brito

Dissertations and Theses

Macroecological studies that predict genetic diversity and its correlation with other biodiversity dimensions are essential to conservation in a rapidly changing environment. However, in bats (order Chiroptera), studies associating abiotic or ecological traits that could help to predict genetic diversity are scarce, even for singular species. In the Neotropics, the highest concentration of mammal and amphibian genetic diversity has been found in the Andes mountains and the Amazon Rainforest, yet it is an open question whether bat genetic diversity is also higher in these regions, or even if any abiotic factors are correlated with bat genetic diversity. Additionally, it is …

Analysis Of Uncertainty In Hydrometeorological Ensemble Forecasts, Carolien N. Mossel

Dissertations and Theses

Ensemble hydrometeorological forecasting has great potential for improving flood predictions and use in water management systems, however, the amount of data used and created with an ensemble forecast requires a careful and intentional approach to understand how useful and skillful the forecast is. The NOAA National Water Model (NWM) was run using downscaled NOAA Global Ensemble Forecast System (GEFS) meteorological forcings for the 2016-2017 wet season (October-March) in California to create an 11-member hydrologic forecast ensemble. To evaluate the performance of these ensemble forecasts, we chose to study streamflow sites within Sonoma County, California, a rain-dominated region which includes the …

Comparison Of Calculated Normal Mode Molecular Vibrations With Experimental Gas-Phase Infrared Spectroscopy, Anila Renis Sutar

Dissertations and Theses

Computational vibrational spectroscopy serves as an important tool in the interpretation of experimental infrared (IR) spectra. Analysis of computational results provides a perspective over broader wavelength ranges and at higher precision. Although there are issues regarding accuracy, this can be approximated by using a scaling factor. High-resolution gas-phase FTIR spectroscopy at a resolution of 0.125 cm^-1 can partially resolve rovibrational transitions in the P, Q, and R bands and therefore identify fundamental frequencies with approximately 1 cm^-1 precision.

This research has compared high-resolution gas-phase FTIR absorption peaks to calculated vibrational frequencies. In the calculation of normal mode frequencies, …

Adsorption Kinetics And Phase Behavior Of Particles Adsorbed At An Interface, Shaghayegh Darjani

Dissertations and Theses

The ability to predict the adsorption dynamic, phase behavior, and surface pressure of a monolayer of adsorbed particles in two-dimensional systems are key aspects of many current research areas. Examples include phase transitions in amphiphilic monolayers, emulsion stability due to particle adsorption at interfaces, and melting at an interface.

In this thesis, a new approach for deriving the equation of state for a two-dimensional lattice gas is proposed, based on arguments similar to those used in the derivation of the Langmuir-Szyszkowski equation of state for localized adsorption. This work aims to predict the adsorption kinetics and phase behavior of a …

A New Mathematical Theory For The Dynamics Of Large Tumor Populations, A Potential Mechanism For Cancer Dormancy & Recurrence And Experimental Observation Of Melanoma Progression In Zebrafish, Adeyinka A. Lesi

Dissertations and Theses

Cancer, a family of over a hundred disease varieties, results in 600,000 deaths in the U.S. alone. Yet, improvements in imaging technology to detect disease earlier, pharmaceutical developments to shrink or eliminate tumors, and modeling of biological interactions to guide treatment have prevented millions of deaths. Cancer patients with initially similar disease can experience vastly different outcomes, including sustained recovery, refractory disease or, remarkably, recurrence years after apparently successful treatment. The current understanding of such recurrences is that they depend on the random occurrence of critical mutations. Clearly, these biological changes appear to be sufficient for recurrence, but are they …

Coordinated Control For Dc Energy Hubs Involving Ders, Evs, And Subway Systems, Rohama Ahmad

Dissertations and Theses

No abstract provided.

Goes-R Supervised Machine Learning, Ronald Adomako

Dissertations and Theses

The GOES-R series is a product line of four satellite, with two currently on-orbit (GOES-16 “East” and GOES-17 “West”). GOES-17 is susceptible to a Loop-Heat-Pipe (LHP) phenomenon where during Fall and Spring seasons, there are times of day where some of the infrared bands records inaccurate readings from the Advanced Baseline Imager (ABI). This occurs from joint astronomical behavior and position of the GOES-17. This calibration issue occurs when the LHP instrument fails to radiate the heat of the sun out of ABI. Predictive Calibration (pCal) is an algorithm developed by instrument vendors for the National Oceanic Atmospheric Agency (NOAA) …

Blockchain-Based Architecture For Secured Cyberattack Signatures And Features Distribution, Oluwaseyi J. Ajayi

Dissertations and Theses

One effective way of detecting malicious traffic in computer networks is intrusion detection systems (IDS). Despite the increased accuracy of IDSs, distributed or coordinated attacks can still go undetected because of the single vantage point of the IDSs. Due to this reason, there is a need for attack characteristics' exchange among different IDS nodes. Another reason for IDS coordination is that a zero-day attack (an attack without a known signature) experienced in organizations located in different regions is not the same. Collaborative efforts of the participating IDS nodes can stop more attack threats if IDS nodes exchange these attack characteristics …

Molecular To Macroscopic Understanding Of Chloroaluminate Anion Intercalation In Rechargeable Aluminum-Graphite Batteries, Jeffrey Xu

Dissertations and Theses

Today’s global energy challenges pose an urgent need to electrify transportation and better store intermittent renewable energy sources (e.g., solar and wind energy). For such large-scale battery applications, aluminum batteries are a promising “beyond lithium-ion” technology due to the high volumetric capacity, earth abundance, low-cost, and inherent safety of aluminum metal. However, there are very few compatible positive electrode materials that exhibit high energy density and cycling stability, in part due to the challenges of electrochemically intercalating highly charged Al³⁺ cations. Recently, graphite has been demonstrated as a promising positive electrode material in non-aqueous rechargeable aluminum batteries, which store …

Understanding The Effect Of Climate And Hydrometeorological Extremes On Natural And Human-Induced Hydrosystems, Jeongwoo Hwang

Dissertations and Theses

The contemporary hydrosystems of the United States involve a complex combination of natural and modified basins in the presence of changing climate and anthropogenic impacts. An enhanced understanding of the interdependence between climate forcings, human-induced interventions, and water balance in both natural and modified basins are essential for developing reliable and resilient hydrosystems and for better water resources management. In response, this dissertation focuses on investigating the hydroclimatology of natural and modified basins across the contiguous United States. It has three research objectives: (1) to explain flow alterations due to anthropogenic activities, especially dam operations, in modified basins and understand …

Control Hierarchies For Critical Infrastructures In Smart Grid Using Reinforcement Learning And Metaheuristic Optimization, Oindrilla Dutta

Dissertations and Theses

The objective of this work is to develop robust control framework for interdependent smart grid infrastructures comprising two critical infrastructures: 1) power distribution networks that are characterized by high penetration of distributed energy resources (DERs), and 2) DC-rail transportation systems in congested urban areas. The rising integration of DERs into the power grid is causing a paradigm shift in the power distribution network. Consequently, new control challenges for efficient and robust operation of the power grid have surfaced. For instance, the intermittency of renewable energy resources necessitates coordinated control of power flows, voltage regulators, and protection device settings of the …

Investigating The Effect Of Electrolyte Concentration And Charging Protocol On Materials Utilization In Rechargeable Zinc Manganese Dioxide Batteries, Snehal H. Kolhekar

Dissertations and Theses

Achieving a highly cyclable, high energy density battery with MnO₂ cathodes encounters many obstacles. Chief among these is the inability of the widely-used γ-MnO₂ polymorph to retain its structural integrity when cycled to near full one-electron discharge capacity, which is about 280mAh/g for commercially available electrolytic manganese dioxide (EMD). In this one-electron range, discharge occurs by proton insertion producing Mn⁺³ which then reverts to γ-MnO₂ on charging. In the first part of the thesis, we investigate the root cause of failure of MnO₂ cathodes under deep cycling in the one-electron discharge range and establish a …

Voltage Security Optimization For Power Transmission Systems, Tamer Ibrahim

Dissertations and Theses

This project proposes an optimization approach for day-ahead reactive power planning to ensure voltage security in transmission networks. The problem is formulated as a voltage-secure multi-period optimal reactive power dispatch (MP-ORPD) problem. The optimization approach searches for optimal set-points of dynamic and static reactive power (var) resources. Specifically, the output includes set-points for switching shunts, transformer taps, and voltage magnitudes at the regulated buses. The primary goal is to maximize the dynamic reactive power reserve of the system, by minimizing the reactive power supplied by synchronous generators. The secondary goal is to minimize changes in the settings of switching shunts …

The Diffuse Bounce Back Lattice Boltzmann Method And Its Applications On The Study Of Fluid-Particle Interactions, Geng Liu

Dissertations and Theses

Fluid-structure interaction is very broadly seen and widely used in many industrial, engineering and environmental processes. The lattice Boltzmann method has been preferred for simulating particulate flows due to its advantages of easy implementation, micro- and mesoscopic physical insights and parallel algorithm. Both sharp and diffuse boundary treatments are studied to recover curved and moving boundaries on structured orthogonal grids for the lattice Boltzmann method. These methods can describe curved boundaries more accurately and more smoothly than the naive staircase approximation. However, to improve the order of velocity accuracy and to reduce the fluctuation of force, either interpolation or additional …

Free-Space Nonreciprocal Transmission Based On Nonlinear Coupled Fano Metasurfaces, Ahmed Mekawy, Dimitrios L. Sounas, Andrea Alù

Advanced Science Research Center

Optical nonlinearities can enable unusual light–matter interactions, with functionalities that would be otherwise inaccessible relying only on linear phenomena. Recently, several studies have harnessed the role of optical nonlinearities to implement nonreciprocal optical devices that do not require an external bias breaking time-reversal symmetry. In this work, we explore the design of a metasurface embedding Kerr nonlinearities to break reciprocity for free-space propagation, requiring limited power levels. After deriving the general design principles, we demonstrate an all-dielectric flat metasurface made of coupled nonlinear Fano silicon resonant layers realizing large asymmetry in optical transmission at telecommunication frequencies. We show that the …

Designed And Biologically Active Protein Lattices, Shih-Ting Wang, Brian Minevich, Jianfang Liu, Honghu Zhang, Dmytro Nykypanchuk, James Byrnes, Wu Liu, Lev Bershadsky, Qun Liu, Tong Wang, Gang Ren, Oleg Gang

Advanced Science Research Center

Versatile methods to organize proteins in space are required to enable complex biomaterials, engineered biomolecular scaffolds, cell-free biology, and hybrid nanoscale systems. Here, we demonstrate how the tailored encapsulation of proteins in DNA-based voxels can be combined with programmable assembly that directs these voxels into biologically functional protein arrays with prescribed and ordered two-dimensional (2D) and three-dimensional (3D) organizations. We apply the presented concept to ferritin, an iron storage protein, and its iron-free analog, apoferritin, in order to form single-layers, double-layers, as well as several types of 3D protein lattices. Our study demonstrates that internal voxel design and intervoxel encoding …