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Range Information Characterization Of The Hokuyo Ust-20lx Lidar Sensor, Matthew A. Cooper, John F. Raquet, Rick Patton May 2018

Range Information Characterization Of The Hokuyo Ust-20lx Lidar Sensor, Matthew A. Cooper, John F. Raquet, Rick Patton

Faculty Publications

This paper presents a study on the data measurements that the Hokuyo UST-20LX Laser Rangefinder produces, which compiles into an overall characterization of the LiDAR sensor relative to indoor environments. The range measurements, beam divergence, angular resolution, error effect due to some common painted and wooden surfaces, and the error due to target surface orientation are analyzed. It was shown that using a statistical average of sensor measurements provides a more accurate range measurement. It was also shown that the major source of errors for the Hokuyo UST-20LX sensor was caused by something that will be referred to as “mixed …

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Analyzing Operating And Support Costs For Air Force Aircraft, Scott C. Hewitson, Jonathan D. Ritschel, Edward D. White, Gregory Brown May 2018

Analyzing Operating And Support Costs For Air Force Aircraft, Scott C. Hewitson, Jonathan D. Ritschel, Edward D. White, Gregory Brown

Faculty Publications

Purpose: Recent legislation resulted in an elevation of operating and support (O&S) costs’ relative importance for decision-making in Department of Defense programs. However, a lack of research in O&S hinders a cost analyst’s abilities to provide accurate sustainment estimates. Thus, the purpose of this paper is to investigate when Air Force aircraft O&S costs stabilize and to what degree. Next, a parametric O&S model is developed to predict median O&S costs for use as a new tool for cost analyst practitioners.
Design/Methodology/Approach: Utilizing the Air Force total ownership cost database, 44 programs consisting of 765 observations from 1996 to 2016 …

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Additive List Coloring Of Planar Graphs With Given Girth, Axel Brandt, Sogol Jahanbekam, Jennifer Diemunsch May 2018

Additive List Coloring Of Planar Graphs With Given Girth, Axel Brandt, Sogol Jahanbekam, Jennifer Diemunsch

Faculty Publications

An additive coloring of a graph G is a labeling of the vertices of G from {1,2,...,k} such that two adjacent vertices have distinct sums of labels on their neighbors. The least integer k for which a graph G has an additive coloring is called the additive coloring number of G, denoted \luck(G). Additive coloring is also studied under the names lucky labeling and open distinguishing. In this paper, we improve the current bounds on the additive coloring number for particular classes of graphs by proving results for a list version of additive coloring. We apply the discharging method and …

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Search For Tensor, Vector, And Scalar Polarizations In The Stochastic Gravitational-Wave Background, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier, S. Appert, K. Arai, M. C. Araya May 2018

Search For Tensor, Vector, And Scalar Polarizations In The Stochastic Gravitational-Wave Background, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier, S. Appert, K. Arai, M. C. Araya

Faculty Publications

The detection of gravitational waves with Advanced LIGO and Advanced Virgo has enabled novel tests of general relativity, including direct study of the polarization of gravitational waves. While general relativity allows for only two tensor gravitational-wave polarizations, general metric theories can additionally predict two vector and two scalar polarizations. The polarization of gravitational waves is encoded in the spectral shape of the stochastic gravitational-wave background, formed by the superposition of cosmological and individually unresolved astrophysical sources. Using data recorded by Advanced LIGO during its first observing run, we search for a stochastic background of generically polarized gravitational waves. We find …

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Constraints On Cosmic Strings Using Data From The First Advanced Ligo Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, K. Arai, M. C. Araya, J. S. Areeda May 2018

Constraints On Cosmic Strings Using Data From The First Advanced Ligo Observing Run, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, P. Ajith, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. Antier, S. Appert, K. Arai, M. C. Araya, J. S. Areeda

Faculty Publications

Cosmic strings are topological defects which can be formed in grand unified theory scale phase transitions in the early universe. They are also predicted to form in the context of string theory. The main mechanism for a network of Nambu-Goto cosmic strings to lose energy is through the production of loops and the subsequent emission of gravitational waves, thus offering an experimental signature for the existence of cosmic strings. Here we report on the analysis conducted to specifically search for gravitational-wave bursts from cosmic string loops in the data of Advanced LIGO 2015-2016 observing run (O1). No evidence of such …

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Full Band All-Sky Search For Periodic Gravitational Waves In The O1 Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier, S. Appert, K. Arai, M. C. Araya, J. S. Areeda May 2018

Full Band All-Sky Search For Periodic Gravitational Waves In The O1 Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier, S. Appert, K. Arai, M. C. Araya, J. S. Areeda

Faculty Publications

We report on a new all-sky search for periodic gravitational waves in the frequency band 475-2000 Hz and with a frequency time derivative in the range of [-1.0,+0.1]×10-8 Hz/s. Potential signals could be produced by a nearby spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. This search uses the data from Advanced LIGO's first observational run O1. No gravitational-wave signals were observed, and upper limits were placed on their strengths. For completeness, results from the separately published low-frequency search 20-475 Hz are included as well. Our lowest upper limit on worst-case (linearly polarized) strain amplitude h0 is ∼4×10-25 …

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Challenging Local Realism With Human Choices, C. Abellán, A. Acín, A. Alarcón, O. Alibart, C. K. Andersen, F. Andreoli, A. Beckert, F. A. Beduini, A. Bendersky, M. Bentivegna, P. Bierhorst, D. Burchardt, A. Cabello, J. Cariñe, S. Carrasco, G. Carvacho, D. Cavalcanti, R. Chaves, J. Cortés-Vega, A. Cuevas, A. Delgado, H. De Riedmatten, C. Eichler, P. Farrera, J. Fuenzalida, M. García-Matos, R. Garthoff, S. Gasparinetti, T. Gerrits, F. Ghafari Jouneghani, S. Glancy, E. S. Gómez, P. González May 2018

Challenging Local Realism With Human Choices, C. Abellán, A. Acín, A. Alarcón, O. Alibart, C. K. Andersen, F. Andreoli, A. Beckert, F. A. Beduini, A. Bendersky, M. Bentivegna, P. Bierhorst, D. Burchardt, A. Cabello, J. Cariñe, S. Carrasco, G. Carvacho, D. Cavalcanti, R. Chaves, J. Cortés-Vega, A. Cuevas, A. Delgado, H. De Riedmatten, C. Eichler, P. Farrera, J. Fuenzalida, M. García-Matos, R. Garthoff, S. Gasparinetti, T. Gerrits, F. Ghafari Jouneghani, S. Glancy, E. S. Gómez, P. González

Faculty Publications

A Bell test is a randomized trial that compares experimental observations against the philosophical worldview of local realism 1, in which the properties of the physical world are independent of our observation of them and no signal travels faster than light. A Bell test requires spatially distributed entanglement, fast and high-efficiency detection and unpredictable measurement settings 2,3 . Although technology can satisfy the first two of these requirements 4-7, the use of physical devices to choose settings in a Bell test involves making assumptions about the physics that one aims to test. Bell himself noted this weakness in using physical …

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Improved Space Object Detection Using Short-Exposure Image Data With Daylight Background, David J. Becker, Stephen C. Cain May 2018

Improved Space Object Detection Using Short-Exposure Image Data With Daylight Background, David J. Becker, Stephen C. Cain

Faculty Publications

No abstract provided.

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Physical Processes Dictate Early Biogeochemical Dynamics Of Soil Pyrogenic Organic Matter In A Subtropical Forest Ecosystem, Jason Stuart, Russell Anderson, Patrick Lazzarino, Kevin A. Kuehn, Omar R. Harvey May 2018

Physical Processes Dictate Early Biogeochemical Dynamics Of Soil Pyrogenic Organic Matter In A Subtropical Forest Ecosystem, Jason Stuart, Russell Anderson, Patrick Lazzarino, Kevin A. Kuehn, Omar R. Harvey

Faculty Publications

Quantifying links between pyOM dynamics, environmental factors and processes is central to predicting ecosystem function and response to future perturbations. In this study, changes in carbon (TC), nitrogen (TN), pH, and relative recalcitrance (R50) for pineand cordgrass-derived pyOM were measured at 3–6 weeks intervals throughout the first year of burial in the soil. Objectives were to (1) identify key environmental factors and processes driving early-stage pyOM dynamics, and (2) develop quantitative relationships between environmental factors and observed changes in pyOM properties. The study was conducted in sandy soils of a forested ecosystem within the Longleaf pine range of the United …

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Uswhy Does Not The Leaf Weight-Area Allometry Of Bamboos Follow The 3/2-Power Law?, Shuyan Lin, Lijuan Shao, Cang Hui, Yu Song, Gadi V.P. Reddy, Johan Gielis, Fang Li, Yulong Ding, Qiang Wei, Peijian Shi May 2018

Uswhy Does Not The Leaf Weight-Area Allometry Of Bamboos Follow The 3/2-Power Law?, Shuyan Lin, Lijuan Shao, Cang Hui, Yu Song, Gadi V.P. Reddy, Johan Gielis, Fang Li, Yulong Ding, Qiang Wei, Peijian Shi

Faculty Publications

The principle of similarity (Thompson, 1917) states that the weight of an organismfollows the 3/2-power law of its surface area and is proportional to its volume on the condition that the density is constant. However, the allometric relationship between leaf weight and leaf area has been reported to greatly deviate from the 3/2-power law, with the irregularity of leaf density largely ignored for explaining this deviation. Here, we choose 11 bamboo species to explore the allometric relationships among leaf area (A), density (ρ), length (L), thickness (T), and weight (W). Because the edge of a bamboo leaf follows a simplified …

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Absence Of Point Spectrum For The Self-Dual Extended Harper's Model, Rui Han May 2018

Absence Of Point Spectrum For The Self-Dual Extended Harper's Model, Rui Han

Faculty Publications

We give a simple proof of absence of point spectrum for the self-dual extended Harper's model. We get a sharp result which improves that of [1] in the isotropic self-dual regime.

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Numerical Methods For A Two-Species Competition-Diffusion Model With Free Boundaries, Shuang Liu, Xinfeng Liu May 2018

Numerical Methods For A Two-Species Competition-Diffusion Model With Free Boundaries, Shuang Liu, Xinfeng Liu

Faculty Publications

The systems of reaction-diffusion equations coupled with moving boundaries defined by Stefan condition have been widely used to describe the dynamics of spreading population and with competition of two species. To solve these systems numerically, new numerical challenges arise from the competition of two species due to the interaction of their free boundaries. On the one hand, extremely small time steps are usually needed due to the stiffness of the system. On the other hand, it is always difficult to efficiently and accurately handle the moving boundaries especially with competition of two species. To overcome these numerical difficulties, we introduce …

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Event-Based Climatology Of Tropical Cyclone Rainfall In Houston, Texas And Miami, Florida, Jill C. Trepanier, Clay S. Tucker May 2018

Event-Based Climatology Of Tropical Cyclone Rainfall In Houston, Texas And Miami, Florida, Jill C. Trepanier, Clay S. Tucker

Faculty Publications

Tropical cyclone (TC) rainfall amounts are compared from 1950-2017 for Houston, Texas and Miami, Florida to estimate the risk of TC rain in both cities. Following the wake of Hurricanes Harvey and Irma in 2017, concern has risen over the future of raininess in these locations. Per-event rainfall amounts are aggregated using tracks taken from HURDAT, time-of-rain gathered from National Weather Service daily weather maps, and rainfall totals taken from airport monitoring stations. Risk analysis tools include descriptive statistics, time series, and return frequencies for Houston and Miami, and spatially interpolated surfaces for Hurricanes Harvey and Irma. The season duration …

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Small-Angle X-Ray Scattering In Amorphous Silicon: A Computational Study, Durga Paudel, Raymond Atta-Fynn, David A. Drabold, Stephen R. Elliott, Parthapratim Biswas May 2018

Small-Angle X-Ray Scattering In Amorphous Silicon: A Computational Study, Durga Paudel, Raymond Atta-Fynn, David A. Drabold, Stephen R. Elliott, Parthapratim Biswas

Faculty Publications

We present a computational study of small-angle x-ray scattering (SAXS) in amorphous silicon (α-Si) with particular emphasis on the morphology and microstructure of voids. The relationship between the scattering intensity in SAXS and the three-dimensional structure of nanoscale inhomogeneities or voids is addressed by generating large high-quality (α-Si networks with 0.1%–0.3% volume concentration of voids, as observed in experiments using SAXS and positron annihilation spectroscopy. A systematic study of the variation of the scattering intensity in the small-angle scattering region with the size, shape, number density, and the spatial distribution of the voids in the networks is presented. Our results …

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Changes In Physicochemical Properties And Starch Crystallinity Of Sponge Cake Containing Hpmc And Extra Virgin Coconut Oil During Room Temperature Storage, Naratip Poonnakasem, Kalaya Laohasongkram, Saiwarun Chaiwanichsiri, Witoon Prinyawiwatkul May 2018

Changes In Physicochemical Properties And Starch Crystallinity Of Sponge Cake Containing Hpmc And Extra Virgin Coconut Oil During Room Temperature Storage, Naratip Poonnakasem, Kalaya Laohasongkram, Saiwarun Chaiwanichsiri, Witoon Prinyawiwatkul

Faculty Publications

Starch retrogradation is an important factor affecting cake firmness. Effects of hydroxy-propyl-methylcellulose (HPMC) at 0.5% (w/w) or extra virgin coconut oil (EVCO) at 20% (w/w), either alone or together, on physicochemical properties and starch crystallinity of sponge cake during storage was investigated. Addition of EVCO increased specific volume and expansion ratio, while addition of HPMC increased water activity of the freshly baked sponge cake. Changes in firmness, moisture, and spin-lattice relaxation time from nuclear magnetic resonance (T1) of sponge cakes followed a first-order kinetic reaction. Use of HPMC and/or EVCO in sponge cake could retard the firmness rate in the …

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Particular Solutions Of Products Of Helmholtz-Type Equations Using The Matern Function, Xiao-Yan Liu, Ching-Shyang Chen, Wen Li, Ming Li May 2018

Particular Solutions Of Products Of Helmholtz-Type Equations Using The Matern Function, Xiao-Yan Liu, Ching-Shyang Chen, Wen Li, Ming Li

Faculty Publications

We derive closed-form particular solutions for Helmholtz-type partial differential equations. These are derived explicitly using the Matern basis functions. The derivation of such particular solutions is further extended to the cases of products of Helmholtz-type operators in two and three dimensions. The main idea of the paper is to link the derivation of the particular solutions to the known fundamental solutions of certain differential operators. The newly derived particular solutions are used, in the context of the method of particular solutions, to solve boundary value problems governed by a certain class of products of Helmholtz-type equations. The leave-one-out cross validation …

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Hadronic Lorentz Violation In Chiral Perturbation Theory Including The Coupling To External Fields, Rasha Kamand, Brett David Altschul, Matthias R. Schindler May 2018

Hadronic Lorentz Violation In Chiral Perturbation Theory Including The Coupling To External Fields, Rasha Kamand, Brett David Altschul, Matthias R. Schindler

Faculty Publications

If any violation of Lorentz symmetry exists in the hadron sector, its ultimate origins must lie at the quark level. We continue the analysis of how the theories at these two levels are connected, using chiral perturbation theory. Considering a 2-flavor quark theory, with dimension-4 operators that break Lorentz symmetry, we derive a low-energy theory of pions and nucleons that is invariant under local chiral transformations and includes the coupling to external fields. The pure meson and baryon sectors, as well as the couplings between them and the couplings to external electromagnetic and weak gauge fields, contain forms of Lorentz …

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The Stellar Populations Of Two Ultra-Diffuse Galaxies From Optical And Near-Infrared Photometry, Viraj Pandya, Aaron J. Romanowsky, Seppo Laine, Jean Brodie, Benjamin Johnson, William Glaccum, Alexa Villaume, Jean-Charles Cuillandre, Stephen Gwyn, Jessica Krick, Ronald Lasker, Ignacio Martín-Navarro, David Martinez-Delgado, Pieter Van Dokkum Apr 2018

The Stellar Populations Of Two Ultra-Diffuse Galaxies From Optical And Near-Infrared Photometry, Viraj Pandya, Aaron J. Romanowsky, Seppo Laine, Jean Brodie, Benjamin Johnson, William Glaccum, Alexa Villaume, Jean-Charles Cuillandre, Stephen Gwyn, Jessica Krick, Ronald Lasker, Ignacio Martín-Navarro, David Martinez-Delgado, Pieter Van Dokkum

Faculty Publications

We present observational constraints on the stellar populations of two ultra-diffuse galaxies (UDGs) using optical through near-infrared (NIR) spectral energy distribution (SED) fitting. Our analysis is enabled by new Spitzer-IRAC 3.6 and 4.5 μm imaging, archival optical imaging, and the prospectorfully Bayesian SED fitting framework. Our sample contains one field UDG (DGSAT I), one Virgo cluster UDG (VCC 1287), and one Virgo cluster dwarf elliptical for comparison (VCC 1122). We find that the optical–NIR colors of the three galaxies are significantly different from each other. We infer that VCC 1287 has an old (7.7 Gyr) and surprisingly metal-poor …

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Upper Limits On The Presence Of Central Massive Black Holes In Two Ultra-Compact Dwarf Galaxies In Centaurus A, Karina Voggel, Anil Seth, Nadine Neumayer, Steffen Mieske, Igor Chilingarian, Christopher Ahn, Holger Baumgardt, Michael Hilker, Dieu Nguyen, Aaron J. Romanowsky, Jonelle Walsh, Mark Den Brok, Jay Strader Apr 2018

Upper Limits On The Presence Of Central Massive Black Holes In Two Ultra-Compact Dwarf Galaxies In Centaurus A, Karina Voggel, Anil Seth, Nadine Neumayer, Steffen Mieske, Igor Chilingarian, Christopher Ahn, Holger Baumgardt, Michael Hilker, Dieu Nguyen, Aaron J. Romanowsky, Jonelle Walsh, Mark Den Brok, Jay Strader

Faculty Publications

The recent discovery of massive black holes (BHs) in the centers of high-mass ultra-compact dwarf galaxies (UCDs) suggests that at least some are the stripped nuclear star clusters of dwarf galaxies. We present the first study that investigates whether such massive BHs, and therefore stripped nuclei, also exist in low-mass (M < 107 M ⊙) UCDs. We constrain the BH masses of two UCDs located in Centaurus A (UCD 320 and UCD 330) using Jeans modeling of the resolved stellar kinematics from adaptive optics data obtained with the SINFONI integral field spectrograph at the Very Large Telescope (VLT/SINFONI). No massive BHs …

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Fitting Als Reflectance Data Using Python, R. Steven Turley Apr 2018

Fitting Als Reflectance Data Using Python, R. Steven Turley

Faculty Publications

This article describes how to use the python refl library in https://bitbucket.org/steve_turley/reflectance-fitting to fit thin film reflectance data from the Advanced Light Source (ALS) at Lawrence Berkeley National Labs. It uses data taken for a thin film of aluminum capped by a thin film of aluminum fluoride on a silicon nitride substrate. The single fit in the example shown here shows the importance of taking into account the oxidation of the aluminum layer as part of the fit.

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Cross-Participant Eeg-Based Assessment Of Cognitive Workload Using Multi-Path Convolutional Recurrent Neural Networks, Ryan G. Hefron, Brett J. Borghetti, Christine M. Schubert Kabban, James Christensen, Justin Estep Apr 2018

Cross-Participant Eeg-Based Assessment Of Cognitive Workload Using Multi-Path Convolutional Recurrent Neural Networks, Ryan G. Hefron, Brett J. Borghetti, Christine M. Schubert Kabban, James Christensen, Justin Estep

Faculty Publications

Applying deep learning methods to electroencephalograph (EEG) data for cognitive state assessment has yielded improvements over previous modeling methods. However, research focused on cross-participant cognitive workload modeling using these techniques is underrepresented. We study the problem of cross-participant state estimation in a non-stimulus-locked task environment, where a trained model is used to make workload estimates on a new participant who is not represented in the training set. Using experimental data from the Multi-Attribute Task Battery (MATB) environment, a variety of deep neural network models are evaluated in the trade-space of computational efficiency, model accuracy, variance and temporal specificity yielding three …

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Uncertainty Evaluation In The Design Of Structural Health Monitoring Systems For Damage Detection, Christine M. Schubert Kabban, Richard P. Uber, Kevin J. Lin, Bin Lin, M. Bhuiyan, Victor Giurgiutiu Apr 2018

Uncertainty Evaluation In The Design Of Structural Health Monitoring Systems For Damage Detection, Christine M. Schubert Kabban, Richard P. Uber, Kevin J. Lin, Bin Lin, M. Bhuiyan, Victor Giurgiutiu

Faculty Publications

The validation of structural health monitoring (SHM) systems for aircraft is complicated by the extent and number of factors that the SHM system must demonstrate for robust performance. Therefore, a time- and cost-efficient method for examining all of the sensitive factors must be conducted. In this paper, we demonstrate the utility of using the simulation modeling environment to determine the SHM sensitive factors that must be considered for subsequent experiments, in order to enable the SHM validation. We demonstrate this concept by examining the effect of SHM system configuration and flaw characteristics on the response of a signal from a …

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Uncertainty Evaluation In The Design Of Structural Health Monitoring Systems For Damage Detection, Christine Schubert Kabban, Richard Uber, Kevin Lin, Bin Li, Md Yeasin Bhuiyan, Victor Giurgiutiu Apr 2018

Uncertainty Evaluation In The Design Of Structural Health Monitoring Systems For Damage Detection, Christine Schubert Kabban, Richard Uber, Kevin Lin, Bin Li, Md Yeasin Bhuiyan, Victor Giurgiutiu

Faculty Publications

The validation of structural health monitoring (SHM) systems for aircraft is complicated by the extent and number of factors that the SHM system must demonstrate for robust performance. Therefore, a time- and cost-efficient method for examining all of the sensitive factors must be conducted. In this paper, we demonstrate the utility of using the simulation modeling environment to determine the SHM sensitive factors that must be considered for subsequent experiments, in order to enable the SHM validation. We demonstrate this concept by examining the effect of SHM system configuration and flaw characteristics on the response of a signal from a …

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Scales Of Seafloor Sediment Resuspension In The Northern Gulf Of Mexico, Arne-R. Diercks, Clayton Dike, Vernon Asper, Steven F. Dimarco, Jeff Chanton, Uta Passow Apr 2018

Scales Of Seafloor Sediment Resuspension In The Northern Gulf Of Mexico, Arne-R. Diercks, Clayton Dike, Vernon Asper, Steven F. Dimarco, Jeff Chanton, Uta Passow

Faculty Publications

Seafloor sediment resuspension events of different scales and magnitudes and the resulting deep (>1,000 m) benthic nepheloid layers were investigated in the northern Gulf of Mexico during Fall 2012 to Summer 2013. Time-series data of size-specific in-situ settling speeds of marine snow in the benthic nepheloid layer (moored flux cameras), particle size distributions (profiling camera), currents (various current meters) and stacked time-series flux data (sediment traps) were combined to recognize resuspension events ranging from small-scale local, to small-scale far-field to hurricane-scale. One smallscale local resuspension event caused by inertial currents was identified based on local high current speeds ( …

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A Route Less Traveled: Principals’ Perceptions Of Alternative Licensed Cte Teachers, Scott R. Bartholomew, Emma P. Bullock, Louis S. Nadelson Apr 2018

A Route Less Traveled: Principals’ Perceptions Of Alternative Licensed Cte Teachers, Scott R. Bartholomew, Emma P. Bullock, Louis S. Nadelson

Faculty Publications

The shortage of teachers prepared to teach career and technical education (CTE) courses, or willing to work in certain locations (e.g. inner city, rural), has motivated the desire to explore solutions such as alternative routes to teacher licensure (ARL). Most ARL programs bypass colleges of education and provide a different approach to preparing individuals to teach, leaving many to wonder about the quality and knowledge of these teachers. Specific areas, such as CTE, have seen a large influx of ARL teachers in recent years. We sought to determine school principals’ perceptions of ARL CTE teachers. We found principal support for …

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Towards Cosmological Dynamics From Loop Quantum Gravity, Bao Fei Li, Parampreet Singh, Anzhong Wang Apr 2018

Towards Cosmological Dynamics From Loop Quantum Gravity, Bao Fei Li, Parampreet Singh, Anzhong Wang

Faculty Publications

We present a systematic study of the cosmological dynamics resulting from an effective Hamiltonian, recently derived in loop quantum gravity using Thiemann's regularization and earlier obtained in loop quantum cosmology (LQC) by keeping the Lorentzian term explicit in the Hamiltonian constraint. We show that quantum geometric effects result in higher than quadratic corrections in energy density in comparison to LQC, causing a nonsingular bounce. Dynamics can be described by the Hamilton or Friedmann-Raychaudhuri equations, but the map between the two descriptions is not one to one. A careful analysis resolves the tension on symmetric versus asymmetric bounce in this model, …

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Functioning Of Coastal River-Dominated Ecosystems And Implications For Oil Spill Response: From Observations To Mechanisms And Models, Adam T. Greer, Alan M. Shiller, Eileen E. Hoffman, Jerry D. Wiggert, Sally J. Warner, Sabrina M. Parra, Chudong Pan, Jeffrey W. Book, Dongjoo Joung, Steven K. Dykstra, Jeffrey W. Krause, Brian Dzwonkowski, Inia M. Soto, M. Kemal Cambazoglu, Alison L. Deary, Christian Briseño-Avena, Adam D. Boyette, Jessica A. Kastler, Virginie Sanial, Laura Hode, Uchenna Nwankwo, Luciano M. Chiaverano, Stephan J. O'Brien, Patrick J. Fitzpatrick, Yee H. Lau, Michael S. Dinniman, Kevin M. Martin, Peng Ho, Allison K. Mojzis, Stephan D. Howden, Frank J. Hernandez, Ian Church, Travis N. Miles, Su Sponaugle, James N. Moum, Robert A. Arnone, Robert K. Cowen, Gregg A. Jacobs, Oscar Schofield, William M. Graham Apr 2018

Functioning Of Coastal River-Dominated Ecosystems And Implications For Oil Spill Response: From Observations To Mechanisms And Models, Adam T. Greer, Alan M. Shiller, Eileen E. Hoffman, Jerry D. Wiggert, Sally J. Warner, Sabrina M. Parra, Chudong Pan, Jeffrey W. Book, Dongjoo Joung, Steven K. Dykstra, Jeffrey W. Krause, Brian Dzwonkowski, Inia M. Soto, M. Kemal Cambazoglu, Alison L. Deary, Christian Briseño-Avena, Adam D. Boyette, Jessica A. Kastler, Virginie Sanial, Laura Hode, Uchenna Nwankwo, Luciano M. Chiaverano, Stephan J. O'Brien, Patrick J. Fitzpatrick, Yee H. Lau, Michael S. Dinniman, Kevin M. Martin, Peng Ho, Allison K. Mojzis, Stephan D. Howden, Frank J. Hernandez, Ian Church, Travis N. Miles, Su Sponaugle, James N. Moum, Robert A. Arnone, Robert K. Cowen, Gregg A. Jacobs, Oscar Schofield, William M. Graham

Faculty Publications

Coastal river-dominated oceans are physically complex, biologically productive, and intimately connected to human socioeconomic activity. The Deepwater Horizon blowout and subsequent advection of oil into coastal waters of the northern Gulf of Mexico (nGOM) highlighted the complex linkages among oceanographic processes within this river-dominated system and knowledge gaps about it that resulted in imprecise information on both oil transport and ecosystem consequences. The interdisciplinary research program implemented through the CONsortium for oil exposure pathways in COastal River-Dominated Ecosystems (CONCORDE) is designed to identify and quantitatively assess key physical, biological, and geochemical processes acting in the nGOM, in order to provide …

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Unconventional Pairing Symmetry Of Interacting Dirac Fermions On A Π -Flux Lattice, Huaiming Guo, Ehsan Khatami, Yao Wang, Thomas Devereaux, Rajiv Singh, Richard Scalettar Apr 2018

Unconventional Pairing Symmetry Of Interacting Dirac Fermions On A Π -Flux Lattice, Huaiming Guo, Ehsan Khatami, Yao Wang, Thomas Devereaux, Rajiv Singh, Richard Scalettar

Faculty Publications

The pairing symmetry of interacting Dirac fermions on the π-flux lattice is studied with the determinant quantum Monte Carlo and numerical linked-cluster expansion methods. The s∗- (i.e., extended s-) and d-wave pairing symmetries, which are distinct in the conventional square lattice, are degenerate under the Landau gauge. We demonstrate that the dominant pairing channel at strong interactions is an unconventional ds∗-wave phase consisting of alternating stripes of s∗- and d-wave phases. A complementary mean-field analysis shows that while the s∗- and d-wave symmetries individually have nodes in the energy spectrum, the ds∗ channel is fully gapped. The results represent a …

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Evaluating And Supporting Teacher Practice Of Formative Assessment: Assessing Posing, Pausing, And Probing Moves, Carrie Holmberg, Brent Duckor Apr 2018

Evaluating And Supporting Teacher Practice Of Formative Assessment: Assessing Posing, Pausing, And Probing Moves, Carrie Holmberg, Brent Duckor

Faculty Publications

Decades of research supports that teacher engagement in formative assessment (FA) can powerfully impact student learning outcomes (Black & Wiliam, 1998; Hattie, 2009, 2012). Yet less is known about teacher development of FA skills on a continuum of practice. This empirical study designed, piloted, and examined test content validity of a performance-based assessment of teachers’ FA practice related to questioning “moves” in the context of six multilingual high needs middle school mathematics classrooms. Qualitative comparative analysis of triangulated evidence of teachers’ planning for, enacting, and reflecting on posing, pausing, and probing “moves” found differences among teachers’ probing in particular, related …

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Unpacking Teacher Practice Through A Moves-Based Formative Assessment Framework Using Video-Based Cycles Of Inquiry, Brent Duckor, Carrie Holmberg Apr 2018

Unpacking Teacher Practice Through A Moves-Based Formative Assessment Framework Using Video-Based Cycles Of Inquiry, Brent Duckor, Carrie Holmberg

Faculty Publications

Research has shown for over a decade that teachers who engage in formative assessment (FA) practices may have the most powerful impact on student learning (Black & Wiliam, 1998; Hattie, 2012). Yet less is known about the development of teachers’ knowledge and use of formative assessment as they plan, enact, and reflect on their questioning practices. Our qualitative case study focuses on how in-service middle school math teachers take up three specific moves (Author A, 2014) associated with formative assessment practice as as part of a video-based cycle of inquiry project. The study found focusing participants’ planning and reflection through …

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