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How Noise Thresholds Affect The Information Content Of Stellar Flare Sequences, Elmer C. Rivera, Jay R. Johnson, Jonathan Homan, Simon Wing Feb 2023

How Noise Thresholds Affect The Information Content Of Stellar Flare Sequences, Elmer C. Rivera, Jay R. Johnson, Jonathan Homan, Simon Wing

Faculty Publications

Systems that exhibit discrete dynamics can be well described and reconstructed by considering the set of time intervals between the discrete events of the system. The Kepler satellite has cataloged light curves for many Sun-like stars, and these light curves show strong bursts in intensity that are associated with stellar flares. The waiting time between these flares describes the fundamental dynamics of the stars and is driven by physical processes, such as flux emergence. While it is rather straightforward to identify large flares, the identification of weaker flares can be challenging because of the presence of noise. A common practice …


Turbulent Mixing Simulation Using The Hierarchical Parcel-Swapping (Hips) Model, Tommy Starick, Masoomeh Behrang, David O. Lignell, Heiko Schmidt, Alan R. Kerstein Feb 2023

Turbulent Mixing Simulation Using The Hierarchical Parcel-Swapping (Hips) Model, Tommy Starick, Masoomeh Behrang, David O. Lignell, Heiko Schmidt, Alan R. Kerstein

Faculty Publications

Turbulent mixing is an omnipresent phenomenon that permanently affects our everyday life. Mixing processes also
plays an important role in many industrial applications. The full resolution of all relevant flow scales often poses a major challenge to the numerical simulation and requires a modeling of the small-scale effects. In transported Probability Density Function (PDF) methods, the simplified modeling of the molecular mixing is a known weak point. At this place, the Hierarchical Parcel-Swapping (HiPS) model developed by A.R. Kerstein [J. Stat. Phys. 153, 142-161 (2013)] represents a computationally efficient and novel turbulent mixing model. HiPS simulates the effects of turbulence …


Three- And Four-Point Functions In Cpt -Even Lorentz-Violating Scalar Qed, Brett Altschul, L. C.T. Brito, J. C.C. Felipe, S. Karki, A. C. Lehum, A. Yu Petrov Feb 2023

Three- And Four-Point Functions In Cpt -Even Lorentz-Violating Scalar Qed, Brett Altschul, L. C.T. Brito, J. C.C. Felipe, S. Karki, A. C. Lehum, A. Yu Petrov

Faculty Publications

The renormalization of quantum field theories usually assumes Lorentz and gauge symmetries, besides the general restrictions imposed by unitarity and causality. However, the set of renormalizable theories can be enlarged by relaxing some of these assumptions. In this work, we consider the particular case of a CPT-preserving but Lorentz-breaking extension of scalar QED. For this theory, we calculate the one-loop radiative corrections to the three- and four-point scalar-vector vertex functions, at the lowest order in the Lorentz-violation parameters, and we explicitly verify that the resulting low-energy effective action is compatible with the usual gauge invariance requirements. With these results, we …


Multicollinearity Applied Stepwise Stochastic Imputation: A Large Dataset Imputation Through Correlation‑Based Regression, Benjamin D. Leiby, Darryl K. Ahner Feb 2023

Multicollinearity Applied Stepwise Stochastic Imputation: A Large Dataset Imputation Through Correlation‑Based Regression, Benjamin D. Leiby, Darryl K. Ahner

Faculty Publications

This paper presents a stochastic imputation approach for large datasets using a correlation selection methodology when preferred commercial packages struggle to iterate due to numerical problems. A variable range-based guard rail modification is proposed that benefits the convergence rate of data elements while simultaneously providing increased confidence in the plausibility of the imputations. A large country conflict dataset motivates the search to impute missing values well over a common threshold of 20% missingness. The Multicollinearity Applied Stepwise Stochastic imputation methodology (MASS-impute) capitalizes on correlation between variables within the dataset and uses model residuals to estimate unknown values. Examination of the …


Enhanced Phase Sensitivity In A Mach-Zehnder Interferometer Via Photon Recycling, Dong Li, Chun Hua Yuan, Xiaoping Ma, Qingle Wang, Hwang Lee, Yao Yao, Weiping Zhang Feb 2023

Enhanced Phase Sensitivity In A Mach-Zehnder Interferometer Via Photon Recycling, Dong Li, Chun Hua Yuan, Xiaoping Ma, Qingle Wang, Hwang Lee, Yao Yao, Weiping Zhang

Faculty Publications

We propose an alternative scheme for phase estimation in a Mach-Zehnder interferometer (MZI) with photon recycling. It is demonstrated that with the same coherent-state input and homodyne detection, our proposal possesses a phase sensitivity beyond the traditional MZI. For instance, it can achieve an enhancement factor of ∼9.32 in the phase sensitivity compared with the conventional scheme even with a photon loss of 10% on the photon-recycled arm. From another point of view, the quantum Cramér-Rao bound (QCRB) is also investigated. It is found that our scheme is able to achieve a lower QCRB than the traditional one. Intriguingly, the …


Evidence Of Sea Level Rise At The Peruvian Coast (1942-2019), Bismarck Jigena-Antelo, Carol Estrada-Ludeña, Stephan Howden, Wilmer Rey, Jorge Paz-Acosta, Patricia Lopez-García, Eric Salazar-Rodriguez, Nieves Endrina, Juan J. Muñoz-Pérez Feb 2023

Evidence Of Sea Level Rise At The Peruvian Coast (1942-2019), Bismarck Jigena-Antelo, Carol Estrada-Ludeña, Stephan Howden, Wilmer Rey, Jorge Paz-Acosta, Patricia Lopez-García, Eric Salazar-Rodriguez, Nieves Endrina, Juan J. Muñoz-Pérez

Faculty Publications

The present work aims to analyze the variability of the sea level of the Peruvian coast with time series over a long observation period (Seventy-eight years, from 1942 to 2019). Data came from the Talara, Callao and Matarani tide gauge stations located at the north, center and south of the coast. Variations of sea level as well as air and seawater surface temperature were analyzed. Among the different scenarios studied, a sea level rise of 6.79, 4.21 and 5.16 mm/year for Talara, Callao and Matarani, respectively was found during the 1979–1997 nodal cycle. However, these results decreased significantly during the …


Measurement Of Proton Light Yield Of Water-Based Liquid Scintillator, E. J. Callaghan, B. L. Goldblum, J. A. Brown, T. A. Laplace, Juan J. Manfredi, M. Yeh, G. D. Orebi Gann Feb 2023

Measurement Of Proton Light Yield Of Water-Based Liquid Scintillator, E. J. Callaghan, B. L. Goldblum, J. A. Brown, T. A. Laplace, Juan J. Manfredi, M. Yeh, G. D. Orebi Gann

Faculty Publications

The proton light yield of liquid scintillators is an important property in the context of their use in large-scale neutrino experiments, with direct implications for neutrino-proton scattering measurements and the discrimination of fast neutrons from inverse β-decay coincidence signals. This work presents the first measurement of the proton light yield of a water-based liquid scintillator (WbLS) formulated from 5% linear alkyl benzene (LAB), at energies below 20 MeV, as well as a measurement of the proton light yield of a pure LAB + 2 g/L 2,5-diphenyloxazole (PPO) mixture (LABPPO). The measurements were performed using a double time-of-flight method and a …


Measurement Of The VE- Nucleus Charged-Current Double-Differential Cross Section At 〈EV⟩ = 2.4 Gev Using Nova, M. A. Acero, P. Adamson, L. Aliaga, N. Anfimov, A. Antoshkin, E. Arrieta-Diaz, L. Asquith, A. Aurisano, A. Back, M. Biard, N. Balashov, P. Baldi, B. A. Bambah, S. Bashar, K. Bays, R. Bernstein, V. Bhatnagar, D. Bhattarai, B. Bhuyan, J. Bian, Roberto Petti, Et. Al. Feb 2023

Measurement Of The VE- Nucleus Charged-Current Double-Differential Cross Section At 〈EV⟩ = 2.4 Gev Using Nova, M. A. Acero, P. Adamson, L. Aliaga, N. Anfimov, A. Antoshkin, E. Arrieta-Diaz, L. Asquith, A. Aurisano, A. Back, M. Biard, N. Balashov, P. Baldi, B. A. Bambah, S. Bashar, K. Bays, R. Bernstein, V. Bhatnagar, D. Bhattarai, B. Bhuyan, J. Bian, Roberto Petti, Et. Al.

Faculty Publications

The inclusive electron neutrino charged-current cross section is measured in the NOvA near detector using 8.02×1020 protons-on-target in the NuMI beam. The sample of GeV electron neutrino interactions is the largest analyzed to date and is limited by ≃17% systematic rather than the ≃7.4% statistical uncertainties. The double-differential cross section in final-state electron energy and angle is presented for the first time, together with the single-differential dependence on Q2 (squared four-momentum transfer) and energy, in the range 1  GeV≤EνGENIE, GiBUU, NEUT, and NuWro neutrino event generators. The data do not strongly favor a model over the …


Reliable Detection Of Location Spoofing And Variation Attacks, Chiho Kim, Sang-Yoon Chang, Dongeun Lee, Jinoh Kim Feb 2023

Reliable Detection Of Location Spoofing And Variation Attacks, Chiho Kim, Sang-Yoon Chang, Dongeun Lee, Jinoh Kim

Faculty Publications

Location spoofing is a critical attack in mobile communications. While several previous studies investigated the detection of location spoofing attacks, they are limited in their performance and lack the consideration of emerging attack variations. In this paper, we present a data-driven methodology for the reliable detection of location spoofing and its variations. To enhance the performance, we introduce and utilize a new set of features, which is differential in nature and enables the checking of the mobility constraints and inconsistency. Our comparison study with the previous research shows that the presented scheme using the new features significantly improves the accuracy …


Emotion Classification Of Indonesian Tweets Using Bidirectional Lstm, Aaron K. Glenn, Phillip M. Lacasse, Bruce A. Cox Feb 2023

Emotion Classification Of Indonesian Tweets Using Bidirectional Lstm, Aaron K. Glenn, Phillip M. Lacasse, Bruce A. Cox

Faculty Publications

Emotion classification can be a powerful tool to derive narratives from social media data. Traditional machine learning models that perform emotion classification on Indonesian Twitter data exist but rely on closed-source features. Recurrent neural networks can meet or exceed the performance of state-of-the-art traditional machine learning techniques using exclusively open-source data and models. Specifically, these results show that recurrent neural network variants can produce more than an 8% gain in accuracy in comparison with logistic regression and SVM techniques and a 15% gain over random forest when using FastText embeddings. This research found a statistical significance in the performance of …


Well Placement Optimization Through The Triple-Completion Gas And Downhole Water Sink-Assisted Gravity Drainage (Tc-Gdws-Agd) Eor Process, Watheq J. Al-Mudhafar, David A. Wood, Dahlia A. Al-Obaidi, Andrew K. Wojtanowicz Feb 2023

Well Placement Optimization Through The Triple-Completion Gas And Downhole Water Sink-Assisted Gravity Drainage (Tc-Gdws-Agd) Eor Process, Watheq J. Al-Mudhafar, David A. Wood, Dahlia A. Al-Obaidi, Andrew K. Wojtanowicz

Faculty Publications

Gas and downhole water sink-assisted gravity drainage (GDWS-AGD) is a new process of enhanced oil recovery (EOR) in oil reservoirs underlain by large bottom aquifers. The process is capital intensive as it requires the construction of dual-completed wells for oil production and water drainage and additional multiple vertical gas-injection wells. The costs could be substantially reduced by eliminating the gas-injection wells and using triple-completed multi-functional wells. These wells are dubbed triple-completion-GDWS-AGD (TC-GDWS-AGD). In this work, we design and optimize the TC-GDWS-AGD oil recovery process in a fictitious oil reservoir (Punq-S3) that emulates a real North Sea oil field. The design …


Effects Of Covid-19 On Sensory And Cognitive Perception Of Mild And Severe Diagnosed And Recovered Patients Versus Healthy Consumers, Adan Cabal-Prieto, Lucía Sánchez-Arellano, José Andrés Herrera-Corredor, Jesús Rodríguez-Miranda, Witoon Prinyawiwatkul, Lorena Guadalupe Ramón-Canul, Filiberto Toledano-Toledano, Ingrid Mayanin Rodríguez-Buenfil, Manuel Octavio Ramírez-Sucre, Gregorio Hernández-Salinas, Emmanuel De Jesús De Ramírez-Rivera Feb 2023

Effects Of Covid-19 On Sensory And Cognitive Perception Of Mild And Severe Diagnosed And Recovered Patients Versus Healthy Consumers, Adan Cabal-Prieto, Lucía Sánchez-Arellano, José Andrés Herrera-Corredor, Jesús Rodríguez-Miranda, Witoon Prinyawiwatkul, Lorena Guadalupe Ramón-Canul, Filiberto Toledano-Toledano, Ingrid Mayanin Rodríguez-Buenfil, Manuel Octavio Ramírez-Sucre, Gregorio Hernández-Salinas, Emmanuel De Jesús De Ramírez-Rivera

Faculty Publications

The objective of this research was to analyze the effects of the SARS-CoV-2 virus on the sensory and cognitive perception of mild and severe COVID-19 diagnosed and recovered consumers versus healthy consumers. Three groups of 50 consumers each (healthy vs. mild and severe COVID-19 diagnosed with 30 days after recovery) were used for the evaluation of instant coffee stimuli in concentrations: 4.40, 2.93, 2.20, 1.76, and 1.47% weight (w)/volume (v) and determine their discriminating power, emotions, and memories. Sensory tests were performed remotely. Results indicated that healthy consumers perceived higher intensities in most of the sensory attributes (with the exception …


Correction To: Parametrized Topological Complexity Of Collision-Free Motion Planning In The Plane (Annals Of Mathematics And Artificial Intelligence, (2022), 90, 10, (999-1015), 10.1007/S10472-022-09801-6), Daniel C. Cohen, Michael Farber, Shmuel Weinberger Feb 2023

Correction To: Parametrized Topological Complexity Of Collision-Free Motion Planning In The Plane (Annals Of Mathematics And Artificial Intelligence, (2022), 90, 10, (999-1015), 10.1007/S10472-022-09801-6), Daniel C. Cohen, Michael Farber, Shmuel Weinberger

Faculty Publications

The article “Parametrized topological complexity of collision-free motion planning in the plane”, written by Daniel C. Cohen, was originally published electronically on the publisher’s internet portal on 07 October 2022 without open access. With the author(s)’ decision to opt for Open Choice the copyright of the article changed on 30 May 2022 to © The Author(s) 2022 and the article is forthwith distributed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a …


Non-Quasiconvex Subgroups Of Hyperbolic Groups Via Stallings-Like Techniques, Pallavi Dani, Ivan Levcovitz Feb 2023

Non-Quasiconvex Subgroups Of Hyperbolic Groups Via Stallings-Like Techniques, Pallavi Dani, Ivan Levcovitz

Faculty Publications

We provide a new method of constructing non-quasiconvex subgroups of hyperbolic groups by utilizing techniques inspired by Stallings’ foldings. The hyperbolic groups constructed are in the natural class of right-angled Coxeter groups (RACGs for short) and can be chosen to be 2-dimensional. More specifically, given a non-quasiconvex subgroup of a (possibly non-hyperbolic) RACG, our construction gives a corresponding non-quasiconvex subgroup of a hyperbolic RACG. We use this to construct explicit examples of non-quasiconvex subgroups of hyperbolic RACGs including subgroups whose generators are as short as possible (length two words), finitely generated free subgroups, non-finitely presentable subgroups, and subgroups of fundamental …


Envirome-Wide Associations Enhance Multi-Year Genome-Based Prediction Of Historical Wheat Breeding Data, Germano Costa-Neto, Leonardo Crespo-Herrera, Nick Fradgley, Keith Gardner, Alison R. Bentley, Susanne Dreisigacker, Roberto Fritsche-Neto, Osval A. Montesinos-López, Jose Crossa Feb 2023

Envirome-Wide Associations Enhance Multi-Year Genome-Based Prediction Of Historical Wheat Breeding Data, Germano Costa-Neto, Leonardo Crespo-Herrera, Nick Fradgley, Keith Gardner, Alison R. Bentley, Susanne Dreisigacker, Roberto Fritsche-Neto, Osval A. Montesinos-López, Jose Crossa

Faculty Publications

Linking high-throughput environmental data (enviromics) to genomic prediction (GP) is a cost-effective strategy for increasing selection intensity under genotype-by-environment interactions (G × E). This study developed a data-driven approach based on Environment–Phenotype Association (EPA) aimed at recycling important G × E information from historical breeding data. EPA was developed in two applications: (1) scanning a secondary source of genetic variation, weighted from the shared reaction-norms of past-evaluated genotypes and (2) pinpointing weights of the similarity among trial-sites (locations), given the historical impact of each envirotyping data variable for a given site. These results were then used as a dimensionality reduction …


Teaching Narrative Interviewing: Reflecting, Narrating, And Becoming-In-Action, Brett H. Bodily, Sherri R. Colby Feb 2023

Teaching Narrative Interviewing: Reflecting, Narrating, And Becoming-In-Action, Brett H. Bodily, Sherri R. Colby

Faculty Publications

Qualitative inquiry teachers often seek powerful pedagogies to improve their students’ understandings. Using our experience leading a doctoral workshop, we share our method for teaching narrative interviewing using Schön’s (1983) “reflection-in-action,” meaning teachers and students reflect in the moment. We also root our pedagogy in Jerome Bruner’s (1986, 1990) narrative as a mode of thinking and a mode of being, a philosophy exploring the ways learners story their own and others’ lives. Describing our doctoral workshop, we highlight Laura, a recent graduate, narrating and becoming a qualitative inquirer. We conclude with a sample teaching lesson, designed to enhance students’ reflective …


Soil Organic Matter Diagenetic State Informs Boreal Forest Ecosystem Feedbacks To Climate Change, Allison N. Myers-Pigg, Karl Kaiser, Ronald Benner, Susan E. Ziegler Feb 2023

Soil Organic Matter Diagenetic State Informs Boreal Forest Ecosystem Feedbacks To Climate Change, Allison N. Myers-Pigg, Karl Kaiser, Ronald Benner, Susan E. Ziegler

Faculty Publications

The fate of soil organic carbon (SOC) in boreal forests is dependent on the integrative ecosystem response to climate change. For example, boreal forest productivity is often nitrogen (N) limited, and climate warming can enhance N cycling and primary productivity. However, the net effect of this feedback on the SOC reservoir and its longevity with climate change remain unclear due to difficulty in detecting small differences between large and variable carbon (C) fluxes needed to determine net changes in soil reservoirs. The diagenetic state of SOC – resulting from the physicochemical and biological transformations that alter the original biomolecular composition …


Drone Detection Using Yolov5, Burchan Aydin, Subroto Singha Feb 2023

Drone Detection Using Yolov5, Burchan Aydin, Subroto Singha

Faculty Publications

The rapidly increasing number of drones in the national airspace, including those for recreational and commercial applications, has raised concerns regarding misuse. Autonomous drone detection systems offer a probable solution to overcoming the issue of potential drone misuse, such as drug smuggling, violating people’s privacy, etc. Detecting drones can be difficult, due to similar objects in the sky, such as airplanes and birds. In addition, automated drone detection systems need to be trained with ample amounts of data to provide high accuracy. Real-time detection is also necessary, but this requires highly configured devices such as a graphical processing unit (GPU). …


Fluvial Flood Losses In The Contiguous United States Under Climate Change, M.M. Rashid, T. Wahl, G. Villarini, A. Sharma Feb 2023

Fluvial Flood Losses In The Contiguous United States Under Climate Change, M.M. Rashid, T. Wahl, G. Villarini, A. Sharma

Faculty Publications

Flooding is one of the most devastating natural disasters causing significant economic losses. One of the dominant drivers of flood losses is heavy precipitation, with other contributing factors such as built environments and socio-economic conditions superimposed to it. To better understand the risk profile associated with this hazard, we develop probabilistic models to quantify the future likelihood of fluvial flood-related property damage exceeding a critical threshold (i.e., high property damage) at the state level across the conterminous United States. The model is conditioned on indicators representing heavy precipitation amount and frequency derived from observed and downscaled precipitation. The likelihood of …


Remote Internal Wave Forcing Of Regional Ocean Simulations Near The U.S. West Coast, Oladeji Q. Siyanbola, Maarten C. Buijsman, Audrey Delpech, Lionel Renault, Roy Barkan, Jay F. Shriver, Brian K. Arbic, James C. Mcwilliams Feb 2023

Remote Internal Wave Forcing Of Regional Ocean Simulations Near The U.S. West Coast, Oladeji Q. Siyanbola, Maarten C. Buijsman, Audrey Delpech, Lionel Renault, Roy Barkan, Jay F. Shriver, Brian K. Arbic, James C. Mcwilliams

Faculty Publications

Low mode internal waves are able to propagate across ocean basins and modulate ocean dynamics thousands of kilometers away from their generation sites. In this study, the impact of remotely generated internal waves on the internal wave energetics near the U.S. West Coast is investigated with realistically forced regional ocean simulations. At the open boundaries, we impose high-frequency oceanic state variables obtained from a global ocean simulation with realistic atmospheric and astronomical tidal forcing. We use the Discrete Fourier Transform (DFT) technique in separating ingoing and outgoing internal tide energy fluxes at the open boundaries in order to quantify internal …


A Simple Micromilled Microfluidic Impedance Cytometer With Vertical Parallel Electrodes For Cell Viability Analysis, Jason Eades, Julianne F. Audiffred, Micah Fincher, Jin Woo Choi, Steven A. Soper, William Todd Monroe Feb 2023

A Simple Micromilled Microfluidic Impedance Cytometer With Vertical Parallel Electrodes For Cell Viability Analysis, Jason Eades, Julianne F. Audiffred, Micah Fincher, Jin Woo Choi, Steven A. Soper, William Todd Monroe

Faculty Publications

Microfluidic impedance cytometry has been demonstrated as an effective platform for single cell analysis, taking advantage of microfabricated features and dielectric cell sensing methods. In this study, we present a simple microfluidic device to improve the sensitivity, accuracy, and throughput of single suspension cell viability analysis using vertical sidewall electrodes fabricated by a widely accessible negative manufacturing method. A microchannel milled through a 75 µm platinum wire, which was embedded into poly-methyl-methacrylate (PMMA), created a pair of parallel vertical sidewall platinum electrodes. Jurkat cells were interrogated in a custom low-conductivity buffer (1.2 ± 0.04 mS/cm) to reduce current leakage and …


Origami-Based Design Of Conceal-And-Reveal Systems, Bryce P. Defigueiredo, Kyler A. Tolman, Spencer P. Magleby, Nathan A. Pehrson, Erica Crampton, Larry L. Howell Jan 2023

Origami-Based Design Of Conceal-And-Reveal Systems, Bryce P. Defigueiredo, Kyler A. Tolman, Spencer P. Magleby, Nathan A. Pehrson, Erica Crampton, Larry L. Howell

Faculty Publications

This work introduces a type of motion termed “conceal-and-reveal” which is characterized by a state that protects a payload, a state that exposes the payload, and coupled motions between these two states. As techniques for thick, rigid origami-based engineering designs are being developed, origami is becoming increasingly more

attractive as inspiration for complex systems. This paper proposes a process for designing origami-based conceal- and-reveal systems, which can be generalized to design similar thick, rigid origami-based systems. The process

is demonstrated through the development of three conceal-and-reveal systems that present a luxury product to the consumer. The three designs also confirm …


Kinematic/Static Model Of Complex Compliant Mechanisms With Serial-Parallel Substructures: A General Approach, Mingxiang Ling, Junyi Cao, Larry L. Howell Jan 2023

Kinematic/Static Model Of Complex Compliant Mechanisms With Serial-Parallel Substructures: A General Approach, Mingxiang Ling, Junyi Cao, Larry L. Howell

Faculty Publications

Kinematic and static analyses of compliant mechanisms are crucial at the early stage of design, and it can be difficult and laborsome for complex configurations with distributed compliance. In this paper, a general and concise kinematic/static modeling method of flexure-hinge-based compliant mechanisms with arbitrary serial-parallel substructures is presented to provide accurate and efficient solutions by combining the matrix displacement method with the transfer matrix method. The transition between the elemental stiffness matrix and the transfer matrix of the flexure hinge and the flexible beam is straightforward, enabling the condensation of a hybrid serial-parallel substructure into one equivalent element simple. Then, …


A Pseudo-Static Model For Dynamic Analysis On Frequency Domain Of Distributed Compliant Mechanisms, Mingxiang Ling, Larry L. Howell, June Cao, Zhou Jiang Jan 2023

A Pseudo-Static Model For Dynamic Analysis On Frequency Domain Of Distributed Compliant Mechanisms, Mingxiang Ling, Larry L. Howell, June Cao, Zhou Jiang

Faculty Publications

This paper presents a pseudo-static modeling methodology for dynamic analysis of distributed compliant mechanisms to provide accurate and efficient solutions. First, a dynamic stiffness matrix of the flexible beam is deduced, which has the same definition and a similar form as the traditional static compliance/stiffness matrix but is frequency-dependent. Second, the pseudo-static modeling procedure for the dynamic analysis is implemented in a statics-similar way. Then, all the kinematic, static and dynamic performances of compliant mechanisms can be analyzed based on the pseudo- static model. The superiority of the proposed method is that when it is used for the dynamic modeling …


Origami-Inspired Sacrificial Joints For Folding Compliant Mechanisms, Todd G. Nelson, Alex Avila, Larry L. Howell, Just L. Herder, Davood Farhadi Machekposhtic Jan 2023

Origami-Inspired Sacrificial Joints For Folding Compliant Mechanisms, Todd G. Nelson, Alex Avila, Larry L. Howell, Just L. Herder, Davood Farhadi Machekposhtic

Faculty Publications

Folding is a manufacturing method which can create complex 3D geometries from flat materi- als and can be particularly useful in cost-sensitive or planar-limited fabrication applications.

This paper introduces compliant mechanisms that employ folding techniques from origami to evolve from a flat material to deployed state. We present origami-inspired sacrificial joints, joints which have mobility during assembly of the mechanism but are rigid in their final position, to create regions of high and low stiffness and the proper alignment of compliant flexures in folded mechanisms. To demonstrate the method we fold steel sheet to create some well-known and complex compliant …


Normalized Coordinate Equations And Energy Method For Predicting Natural Curved-Fold Configurations, Jacob Badger, Todd G. Nelson, Rober J. Lang, Denise M. Halverson, Larry L. Howell Jan 2023

Normalized Coordinate Equations And Energy Method For Predicting Natural Curved-Fold Configurations, Jacob Badger, Todd G. Nelson, Rober J. Lang, Denise M. Halverson, Larry L. Howell

Faculty Publications

Of the many valid configurations that a curved fold may assume, it is of particular interest to identify natural—or lowest energy—configurations that physical models will preferentially assume. We present normalized coordinate equations—equations that relate fold surface properties

to their edge of regression—to simplify curved-fold rela- tionships. An energy method based on these normalized

coordinate equations is developed to identify natural con- figurations of general curved folds. While it has been noted

that natural configurations have nearly planar creases for curved folds, we show that non-planar behavior near the crease ends substantially reduces the energy of a fold.


Soil Microbial Legacies Influence Freeze–Thaw Responses Of Soil, Melissa A. Pastore, Aimee T. Classen, Marie E. English, Serita D. Frey, Melissa A. Knorr, Karin Rand, E. Carol Adair Jan 2023

Soil Microbial Legacies Influence Freeze–Thaw Responses Of Soil, Melissa A. Pastore, Aimee T. Classen, Marie E. English, Serita D. Frey, Melissa A. Knorr, Karin Rand, E. Carol Adair

Faculty Publications

Warmer winters with less snowfall are increasing the frequency of soil freeze–thaw cycles across temperate regions. Soil microbial responses to freeze–thaw cycles vary and some of this variation may be explained by microbial conditioning to prior winter conditions, yet such linkages remain largely unexplored. We investigated how differences in temperature history influenced microbial community composition and activity in response to freeze–thaw cycles.

We collected soil microbial communities that developed under colder (high elevation) and warmer (low elevation) temperature regimes in spruce-fir forests, then added each of these soil microbial communities to a sterile bulk-soil in a laboratory microcosm experiment. The …


Publisher Correction: A Very Luminous Jet From The Disruption Of A Star By A Massive Black Hole (Nature, (2022), 612, 7940, (430-434), 10.1038/S41586-022-05465-8), Igor Andreoni, Michael W. Coughlin, Daniel A. Perley, Yuhan Yao, Wenbin Lu, S. Bradley Cenko, Harsh Kumar, Shreya Anand, Anna Y.Q. Ho, Mansi M. Kasliwal, Antonio De Ugarte Postigo, Ana Sagués-Carracedo, Steve Schulze, D. Alexander Kann, S. R. Kulkarni, Jesper Sollerman, Nial Tanvir, Armin Rest, Luca Izzo, Jean J. Somalwar, David L. Kaplan, Tomás Ahumada, G. C. Anupama, Katie Auchettl, Sudhanshu Barway, Eric C. Bellm, Varun Bhalerao, Joshua S. Bloom, Michael Bremer, Mattia Bulla, Eric Burns, Sergio Campana, Poonam Chandra Jan 2023

Publisher Correction: A Very Luminous Jet From The Disruption Of A Star By A Massive Black Hole (Nature, (2022), 612, 7940, (430-434), 10.1038/S41586-022-05465-8), Igor Andreoni, Michael W. Coughlin, Daniel A. Perley, Yuhan Yao, Wenbin Lu, S. Bradley Cenko, Harsh Kumar, Shreya Anand, Anna Y.Q. Ho, Mansi M. Kasliwal, Antonio De Ugarte Postigo, Ana Sagués-Carracedo, Steve Schulze, D. Alexander Kann, S. R. Kulkarni, Jesper Sollerman, Nial Tanvir, Armin Rest, Luca Izzo, Jean J. Somalwar, David L. Kaplan, Tomás Ahumada, G. C. Anupama, Katie Auchettl, Sudhanshu Barway, Eric C. Bellm, Varun Bhalerao, Joshua S. Bloom, Michael Bremer, Mattia Bulla, Eric Burns, Sergio Campana, Poonam Chandra

Faculty Publications

In the version of this article initially published, there was in an error in the third-to-last sentence of the abstract, now reading, in part, “we calculate a rate of 0.02–0.01 +0.04 Gpc–3 yr–1”, where Gpc was spelled out as gigapascals, not gigaparsecs. Also, the scale label (2″) was missing in the lower-left corner of Fig. 1b. The errors have been corrected in the HTML and PDF versions of the article.


On Limitations Of Uniplex Networks For Modeling Multiplex Contagion, Nicholas W. Landry, Jimi Adams Jan 2023

On Limitations Of Uniplex Networks For Modeling Multiplex Contagion, Nicholas W. Landry, Jimi Adams

Faculty Publications

Many network contagion processes are inherently multiplex in nature, yet are often reduced to processes on uniplex networks in analytic practice. We therefore examine how data modeling choices can affect the predictions of contagion processes. We demonstrate that multiplex contagion processes are not simply the union of contagion processes over their constituent uniplex networks. We use multiplex network data from two different contexts- (1) a behavioral network to represent their potential for infectious disease transmission using a "simple"epidemiological model, and (2) users from online social network sites to represent their potential for information spread using a threshold-based "complex"contagion process. Our …


Externalities,Scarcity And Abundance, Brett M. Frischmann, Giovanni B. Ramello Jan 2023

Externalities,Scarcity And Abundance, Brett M. Frischmann, Giovanni B. Ramello

Faculty Publications

Introduction: Do externalities work and matter differently in a world of scarcity vs. a world of abundance? In this article, we critically examine the economic phenomena of externalities. The concept of externality, an important idea in economics and law, is useful in exploring the complex and dynamic relationships between resource supply and human flourishing within various sociotechnical systems.

Methods: First, we define the basic concept and explain why it is fundamental to economic analysis of complex social environments Second, we briefly survey the intellectual history of externalities with the goal of tying together a few different strands of economic theory …