Digital Commons Network^™

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 …

Neutron Imaging Of Al6061 Prepared By Solid-State Friction Stir Additive Manufacturing, Saber Nemati, Leslie G. Butler, Kyungmin Ham, Gerald L. Knapp, Congyuan Zeng, Selami Emanet, Hamed Ghadimi, Shengmin Guo, Yuxuan Zhang, Hassina Bilheux

Faculty Publications

Solid-state Friction Stir Additive Manufacturing has recently gained attention as a result of its capacity to fabricate large-scale parts while preserving the mechanical properties of the feedstock material. However, the correlation between the quality of layer-by-layer bonding of the deposited metal and processing parameters has remained unknown. Neutron imaging techniques, with 90% total transmission per cm, are employed for Al6061 parts fabricated by MELD® Technology as a non-destructive evaluation approach for the first time to investigate the layer-by-layer structure of a stadium-shaped ingot in different sections. The post-processed results show the fabricated parts with an optimized set of processing parameters …

Hardness Distribution Of Al2050 Parts Fabricated Using Additive Friction Stir Deposition, Hamed Ghadimi, Huan Ding, Selami Emanet, Mojtaba Talachian, Chase Cox, Michael Eller, Shengmin Guo

Faculty Publications

The solid-state additive friction stir deposition (AFSD) process is a layer-by-layer metal 3D-printing technology. In this study, AFSD is used to fabricate Al–Cu–Li 2050 alloy parts. The hardness values for various regions of the as-deposited built parts are measured, and the results are contrasted with those of the feedstock material. The as-fabricated Al2050 parts are found to have a unique hardness distribution due to the location-specific variations in the processing temperature profile. The XRD results indicate the presence of the secondary phases in the deposited parts, and EDS mapping confirms the formation of detectable alloying particles in the as-deposited Al2050 …

Correction: Design Of Crack-Free Laser Additive Manufactured Inconel 939 Alloy Driven By Computational Thermodynamics Method (Mrs Communications, (2022), 12, 5, (844-849), 10.1557/S43579-022-00253-X), Congyuan Zeng, Huan Ding, Uttam Bhandari, S. M. Guo

Faculty Publications

The article Design of crack-free laser additive manufactured Inconel 939 alloy driven by computational thermodynamics method, written by Congyuan Zeng, Huan Ding, Uttam Bhandari, S. M. Guo, was originally published electronically on the publisher’s internet portal on 9 September 2022 without open access. With the author(s)’ decision to opt for Open Choice the copyright of the article changed on 20 December 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 …

Wind Loads On Overhead Sign Structures: A Comparative Study, Aly Mousaad Aly, James Benson

Faculty Publications

Road signs are prone to extreme winds that cause significant damage. Overhead sign structures can disrupt traffic and cause harm to the traveling public if a failure occurs under extreme wind conditions. In this paper, we employ Computational Fluid Dynamics (CFD) in a comparative study to understand the aerodynamics of standard, porous, and curved signs. The study shows the viability of porous and curved overhead boards for lessening aerodynamic loads, which can mini-mize damage and enhance safety on roadways. Porous overhead signs can decrease the drag forces; however, the size of the openings is a vital parameter in reducing wind …

Vibration Attenuation In A High-Rise Hybrid-Timber Building: A Comparative Study, Suvash Chapain, Aly Mousaad Aly

Faculty Publications

Recent developments in engineered timber products, and their availability, durability, and renewability, have led to taller and more flexible buildings. However, these buildings may experience excessive vibrations, resulting in safety and serviceability issues due to wind or earthquake loads. This paper presents a dynamic analysis of a 42-story-tall hybrid-timber building, along with a comparative study of the performance of three damping devices: (i) pendulum pounding tuned mass damper (PTMD), (ii) tuned mass damper inerter (TMDI), and (iii) tuned mass damper (TMD). First, we evaluate the vibration reduction capability of the TMD and the TMDI under filtered white noise and variable …

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 …

Steering Particles Via Micro-Actuation Of Chemical Gradients Using Model Predictive Control, Mark N. Mcdonald, Cameron K. Peterson, Douglas R. Tree

Faculty Publications

Biological systems rely on chemical gradients to direct motion through both chemotaxis and signaling, but synthetic approaches for doing the same are still relatively naïve. Consequently, we present a novel method for using chemical gradients to manipulate the position and velocity of colloidal particles in a microfluidic device. Specifically, we show that a set of spatially localized chemical reactions that are sufficiently controllable can be used to steer colloidal particles via diffusiophoresis along an arbitrary trajectory. To accomplish this, we develop a control method for steering colloidal particles with chemical gradients using nonlinear model predictive control with a model based …

What Factors Make Consumers In The Usa Buy Hemp Products? Evidence From Nielsen Consumer Panel Data, Gwanseon Kim, Mark Tyler

Faculty Publications

This study aims to identify critical consumer-demographic characteristics associated with the consumption of products containing hemp and investigate their effect on total expenditure in the USA. To estimate the likelihood of market participation and consumption level, the Heckman selection model is employed utilizing Nielsen consumer panel data from 2008 to 2015. Using a Heckman selection model, this study finds that socio-demographic characteristics, especially income, age, and education, play an important role in explaining purchases of and demand for different categories of hemp products. Noteworthy is the finding that the role of the age of the household head is mixed with …

Synthesis, Crystal Structure, And Magnetic Properties Of Comofeal And Related Compounds, Gavin Baker, Jax Wysong, Shah Valloppilly, Paul Shand, Pavel Lukashev, Parashu Kharel

Faculty Publications

We have carried out joint theoretical and experimental investigations of three Heusler compounds CoMoFeAl, CoMo0.5Fe1.5Al, and Co1.5Mo0.5FeAl. Our first-principle calculations show that all three compounds show either ferro- or ferrimagnetic order with CoMoFeAl and CoMo0.5Fe1.5Al exhibiting high spin polarization of almost 80%. The investigated samples were prepared using arc melting and high vacuum annealing. All the samples show cubic crystal structure with disorder. The parent compound CoMoFeAl shows a small saturation magnetization of 12 emu/g, and a Curie temperature of 440 K. The other two compounds, namely, Co1.5Mo0.5FeAl and CoMo0.5Fe1.5Al, show much higher saturation magnetizations of 62 emu/g and 59 …

Is A Genetic Diathesis For Poor Nutrition Becoming More Crucial Due To The Uniformity Of Covid Social Stress?, M. Catherine Desoto

Faculty Publications

The important role of nutrition in proper neural functioning and mental health has seen wider acceptance, but is still sadly under recognized given the existent body of research. This Special Issue was designed to unite authoritative information on this topic in one volume. This editorial provides an overview of the issue, and suggests that the combination of social isolation, lack of exercise, and remaining indoors that overtook industrialized societies during 2020 are specific factors expected to change the Gene × Environment interactions for anxiety and depression. Importantly, the recent environmental changes may make biological diatheses for nutritional deficiencies even more …

Review Of Preaching To People In Pain: How Suffering Can Shape Your Sermons And Connect With Your Congregations By Matthew D. Kim, Grand Rapids, Mi: Baker Academic, 2021., Rodney Palmer

Faculty Publications

No abstract provided.

Da Principio: Ancorando L'Etica All'evento Della Creazione, Davide Sciarabba

Faculty Publications

No abstract provided.

Darius Andrews Of Sumner, Maine: An Update, Kathrine C. Aydelott

Faculty Publications

This brief essay is an update to “Darius Andrews of Sumner, Maine: A Descent from Henry Andrews of Taunton, Massachusetts,” which is available online from the University of New Hampshire Scholars’ Repository, which see for context.

Plea Bargaining's Uncertainty Problem, Jeffrey Bellin

Faculty Publications

While commentators roundly condemn plea bargaining, the criticism can be as muddled as the practice itself. Critics’ primary target is the “trial penalty.” But a differential between guilty-plea and trial sentences seems inevitable in any system that allows defendants to concede guilt. And, as a new wave of “progressive prosecutors” is demonstrating, gaps between (unusually lenient) plea offers and long (potential) post-trial sentences are not only a strong incentive to plead guilty but also a powerful tool for reducing American penal severity. Other critiques point to flaws that parallel those found in the broader system, overlooking that plea bargaining is …

Trolley Problems, Private Necessity, And The Duty To Rescue, Laura A. Heymann

Faculty Publications

Laidlaw v. Sage is generally, at best, an oddity in Torts casebooks today. A case that captured the imagination of New York newspaper readers at the time, Laidlaw involved an explosion that, William Laidlaw argued, the wealthy Russell Sage survived only because, at the last moment, he pulled Laidlaw in front of him to absorb the brunt of the blast. As taught in Torts classrooms, Laidlaw is either a case about the intent requirement for battery or a case about causation. But the case, assuming the plaintiff’s story was true, also provides an interesting window into what would seem to …

Crypto Assets And The Problem Of Tax Classifications, Eric D. Chason

Faculty Publications

To date, Internal Revenue Service (I.R.S.) guidance on cryptocurrencies has been thin. When the I.R.S. has issued guidance, it occasionally mishandles the technical details (such as confusing air drops and hard forks). More personnel (and personnel with greater technical expertise) would allow the I.R.S. to keep pace with the explosive growth of cryptocurrency. Nevertheless, the I.R.S. could better leverage its existing resources by focusing on select issues and seeking enabling legislation from Congress. Specifically, the I.R.S. should focus on crypto issues occurring on a system-wide basis and not requiring taxpayer-specific considerations.

For example, determining whether Bitcoin is a “security” under …

Practical Pointers: A Five-Star Church, S. Joseph Kidder

Faculty Publications

No abstract provided.

How To Read Ellen White's Writings Today, Denis Kaiser

Faculty Publications

No abstract provided.

Ash Aerosol Particle Size Distribution, Composition, And Deposition Behavior While Co-Firing Coal And Steam-Exploded Biomass In A 1.5 Mwth Combustor, Rajarshi Roy, Brian Schooff, Xiaolong Li, Scott Montgomery, Jacob Tuttle, Jost O.L. Wendt, Kingsley Dickson, Brian Iverson, Andrew R. Fry

Faculty Publications

Five different blends of Utah bituminous coal and steam-exploded pine (100/0, 75/25, 50/50, 25/75, 0/100 by mass) were fired in a 1.5 MWth combustor. Primary objectives were to understand mineral matter behavior by analyzing aerosol size distribution, aerosol size-segregated composition, ash deposition mass, and ash composition. For particle size < 0.1 μm, pure coal had the lowest aerosol concentration and pure biomass showed the highest (higher nucleation of potassium salts), a trend which reversed for particles >0.1 μm. During pure biomass combustion, aerosol particles >15 μm contained higher mass fractions of potassium (+126%), calcium (+132%), and iron (+115%) and lower fractions of aluminum (−49%) and silicon (−29%) than pure coal. Ash deposition mass decreased with increasing biomass blends. …

Forgotten Brother Reuben Lewis: Missouri River Fur Trader And Indian Agent For The Arkansas Cherokees, Jay H. Buckley, Deveney Reber

Faculty Publications

Reuben Lewis was born in 1777, the fourth and youngest child of William Lewis and Lucy Meriwether. Their oldest child, Jane, married and lived out her days at Locust Hill, the family estate in Virginia. The Lewis’ second child, baby Lucinda, died in infancy. Their third child, Meriwether – the closest in age and friendship to Reuben – became the famous first half of the Lewis and Clark Expedition which explored the uncharted West before he met his tragic and mysterious death on the Natchez Trace in Tennessee. While Reuben’s life has been rightly overshadowed by his older brother Meriwether’s …

Design And Characterization Of An Aerosol Test Chamber For Emergency Response Patient Contamination Control Simulation And Research, Megan L. Steele, Emily M. Spatz, George P. Lemmer, Jacob M. Denney, Casey Cooper, Jeremy M. Slagley, Robert M. Eninger

Faculty Publications

Contaminated or infected patients present a risk of cross-contamination for emergency responders, attending medical personnel and medical facilities as they enter a treatment facility. The controlled conditions of an aerosol test chamber are required to examine factors of contamination, decontamination, and cross-contamination. This study presents the design, construction, and a method for characterizing an aerosol test chamber for a full-sized manikin on a standard North Atlantic Treaty Organization litter. The methodology combined air velocity measurements, aerosol particle counts and size distributions, and computational fluid dynamics modeling to describe the chamber’s performance in three dimensions. This detailed characterization facilitates future experimental …

Laser Powder Bed Fusion Of Molybdenum And Mo-0.1sic Studied By Positron Annihilation Lifetime Spectroscopy And Electron Backscatter Diffraction Method, Nathan E. Ellsworth, Joshua R. Machacek, Ryan A. Kemnitz, Cayla C. Eckley, Brianna M. Sexton, Joel S. Gearhart, Larry W. Burggraf

Faculty Publications

Positron annihilation lifetime spectroscopy (PALS) has been used for the first time to investigate the microstructure of additively manufactured molybdenum. Despite the wide applicability of positron annihilation spectroscopy techniques to the defect analysis of metals, they have only been used sparingly to monitor the microstructural evolution of additively manufactured metals. Molybdenum and molybdenum with a dilute addition (0.1 wt%) of nano-sized silicon carbide, prepared via laser powder bed fusion (LPBF) at four different scan speeds: 100, 200, 400, and 800 mm/s, were studied by PALS and compared with electron backscatter diffraction analysis. The aim of this study was to clarify …

Ads-B Classification Using Multivariate Long Short-Term Memory–Fully Convolutional Networks And Data Reduction Techniques, Sarah Bolton, Richard Dill, Michael R. Grimaila, Douglas Hodson

Faculty Publications

Researchers typically increase training data to improve neural net predictive capabilities, but this method is infeasible when data or compute resources are limited. This paper extends previous research that used long short-term memory–fully convolutional networks to identify aircraft engine types from publicly available automatic dependent surveillance-broadcast (ADS-B) data. This research designs two experiments that vary the amount of training data samples and input features to determine the impact on the predictive power of the ADS-B classification model. The first experiment varies the number of training data observations from a limited feature set and results in 83.9% accuracy (within 10% of …

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.

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 …

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, …

Emotions In Crisis: Consequences Of Ceremonial Refugee Camp Visits To Bhutanese Refugee Camps In Nepal, Kamryn Warren

Faculty Publications

Research on refugee resettlement frequently overlooks the larger context of the experience of forced migration. As a result, the micro-level interactions between refugees and the bureaucrats who make resettlement decisions are obscured. We can better understand the socio-political dynamics between refugees and the officials deciding their resettlement cases if we approach encounters between refugees and migration officials during ceremonial visits as sites of emotional exchange. This article examines the complex socio-political emotional exchanges of power and vulnerability that underpin the refugee resettlement process through an ethnographic analysis of Bhutanese refugee camps in Nepal.

Energy Drinks: The Scourge Of Studying?, Paul A. Djupe

Faculty Publications

No abstract provided.

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 …