Digital Commons Network^™

Fatigue Life Of Pitch- And Stall-Regulated Composite Tidal Turbine Blades, Ciaran R. Kennedy, Vesna Jaksic, Sean B. Leen, Conchúr M. Ó Brádaigh

Publications

Tidal turbine blades are subject to harsh loading and environmental conditions, including large thrust and torsional loadings, relative to wind turbine blades, due to the high density of seawater, among other factors. The complex combination of these loadings, as well as water ingress and associated composite laminate saturation, have significant implications for blade design, affecting overall device design, stability, scalability, energy production and cost-effectiveness. This study investigates the effect of seawater ingress on composite material properties, and the associated design and life expectancy of tidal turbine blades in operating conditions. The fatigue properties of dry and water-saturated glass fibre reinforced …

Gw170817: Implications For The Stochastic Gravitational-Wave Background From Compact Binary Coalescences, B. P. Abbott, K. Aultoneal, S. Gaudio, K. Gill, E. M. Gretarsson, B. Hughey, M. Muratore, J. W. W. Pratt, S. G. Schwalbe, K. Staats, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

The LIGO Scientific and Virgo Collaborations have announced the event GW170817, the first detection of gravitational waves from the coalescence of two neutron stars. The merger rate of binary neutron stars estimated from this event suggests that distant, unresolvable binary neutron stars create a significant astrophysical stochastic gravitational-wave background. The binary neutron star component will add to the contribution from binary black holes, increasing the amplitude of the total astrophysical background relative to previous expectations. In the Advanced LIGO-Virgo frequency band most sensitive to stochastic backgrounds (near 25 Hz), we predict a total astrophysical background with amplitude ΩGW(f=25  Hz)=1.8+2.7−1.3×10−9 with …

Numerical Simulation Of Energy Localization In Dynamic Materials, Arkadi Berezovski, Mihhail Berezovski

Publications

Dynamic materials are artificially constructed in such a way that they may vary their characteristic properties in space or in time, or both, by an appropriate arrangement or control. These controlled changes in time can be provided by the application of an external (non-mechanical) field, or through a phase transition. In principle, all materials change their properties with time, but very slowly and smoothly. Changes in properties of dynamic materials should be realized in a short or quasi-nil time lapse and over a sufficiently large material region. Wave propagation is a characteristic feature for dynamic materials because it is also …

Research Benefits For Scholarly Authors Being Published On A Public Forum, Hunter M. Watson, Brent D. Bowen, Timothy B. Holt, Jacqueline R. Luedtke

Publications

The previous construct of research was focused on social media platforms as a benefactor in broadcasting towards a global audience with non-academic professions. Following along the same ideology, this research directs the attention to a pertained audience in academic profession.

•Embry-Riddle is the host of Scholarly Commons which collects the research of authors (faculty members), and assists in developing a digital portfolio. This portfolio creates metric measurements on a dashboard to indicate where downloads are occurring, and aids in providing current information pertaining to the authors’ publication. •In this case, the publication of the National Airline Quality Rating (AQR) ( …

A Longitudinal Analysis On The Cyclical Pattern Of The U.S. Airline Industry, Michelle M. Bennett, Brent D. Bowen, Jacqueline R. Luedtke, Dean Headley, Timothy B. Holt

Publications

The Airline Quality Rating (AQR) is the nation’s most comprehensive study of airline performance and quality for over two decades. AQR provides consumers and industry watchers a means to compare performance quality among different US airlines using objective performance-based data. This research looks to analyze the cyclical patterns present in AQR in order to identify trends and factors contributing to the changes in these results each year. This research utilizes the application of a longitudinal analysis methodology which will provide the correlation between factors identified and the indicators affected.

Aerodynamic Analysis Of Low Speed Wing Design Using Taguchi L9 Orthogonal Array, Kenneth Witcher, Ian Mcandrew, Elena Vishnevskaya

Publications

The study of aerodynamics has been preoccupied with understanding flight at increasing speeds and ultimately supersonic. Today, this pursuit has advanced the science for both Hypersonic and Transonic flight to near Mach 1 supporting economical commercial flight operations. This research presents the data from a Taguchi array on low speed with twin wing designs to establish the design parameters for their use in low speed and high altitude. Also presented is how aerodynamic advantages can be achieved through understanding the interactions of parameters and their use. This is compared to operational effectiveness when applied to remotely piloted aircraft that are …

All-Sky Search For Long-Duration Gravitational Wave Transients In The First Advanced Ligo Observing Run, B. P. Abbott, K. Gill, B. Hughey, J. W. W. Pratt, E. Rhoades, E. Schmidt, S. G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

We present the results of a search for long-duration gravitational wave transients in the data of the LIGO Hanford and LIGO Livingston second generation detectors between and , with a total observational time of . The search targets gravitational wave transients of 10–500 s duration in a frequency band of 24–2048 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. No significant events were observed. As a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. We also show that the …

Estimating Discharge In Low-Order Rivers With High-Resolution Aerial Imagery, Tyler V. King, Bethany T. Neilson, Mitchell T. Rasmussen

Publications

Remote sensing of river discharge promises to augment in situ gauging stations, but the majority of research in this field focuses on large rivers (>50 m wide). We present a method for estimating volumetric river discharge in low-order (wide) rivers from remotely sensed data by coupling high-resolution imagery with one-dimensional hydraulic modeling at so-called virtual gauging stations. These locations were identified as locations where the river contracted under low flows, exposing a substantial portion of the river bed. Topography of the exposed river bed was photogrammetrically extracted from high-resolution aerial imagery while the geometry of the remaining inundated portion …

Metallic Mxenes: A New Family Of Materials For Flexible Triboelectric Nanogenerators, Yongchang Dong, Sai Sunil Kumar Mallineni, Kathleen Maleski, Herbert Behlow, Vadym N. Mochalin, Apparao M. Rao, Yury Gogosti, Ramakrishna Podila

Publications

Wearable and flexible electronics warrant the development of self-powered devices to circumvent the limitations imposed by traditional energy storage devices. Triboelectric nanogenerators (TENGs) that convert waste mechanical energy from human motion into electric power offer a solution. Highly electronegative and conducting TENG materials that support the generation of both large potential differences and high currents are imperative for effectively harvesting electric power from human muscle movements. Here, we demonstrate that two-dimensional MXenes (e.g., titanium carbide Ti3C2Tx, where Tx stands for surface functional groups such as -O, -OH, and -F) are a family of electrically conducting materials that are triboelectrically more …

A Mean-Risk Mixed Integer Nonlinear Program For Transportation Network Protection, Jie Lu, Akshay Gupte, Yongxi Huang

Publications

This paper focuses on transportation network protection to hedge against extreme events such as earthquakes. Traditional two-stage stochastic programming has been widely adopted to obtain solutions under a risk-neutral preference through the use of expectations in the recourse function. In reality, decision makers hold different risk preferences. We develop a mean-risk two-stage stochastic programming model that allows for greater flexibility in handling risk preferences when allocating limited resources. In particular, the first stage minimizes the retrofitting cost by making strategic retrofit decisions whereas the second stage minimizes the travel cost. The conditional value-at-risk (CVaR) is included as the risk measure …

Exploring Practices Of Science Coordinators Participating In Targeted Professional Development, Brooke A. Whitworth, Jennifer L. Maeng, Randy L. Bell

Publications

This study describes how district science coordinators supported teachers and implemented professional development in their districts following participation in the Science Coordinator Academy. This qualitative descriptive case study comprised three district science coordinators from three districts in a mid‐Atlantic state, as well as principals and teachers from those districts. Data sources, including observations, surveys, artifacts, and interviews, were analyzed using the framework method (Gale, Heath, Cameron, Rashid, & Redwood, 2013). District context, science coordinator background, and collaboration were salient factors that influenced coordinator practices and coordinators’ abilities to impact teacher change. We hypothesize that the development of a coaching relationship, …

Monthly Paleostreamflow Reconstruction From Annual Tree-Ring Chronologies, James H. Stagge, David E. Rosenberg, R. J. Derose, Tammy M. Rittenour

Publications

Paleoclimate reconstructions are increasingly used to characterize annual climate variability prior to the instrumental record, to improve estimates of climate extremes, and to provide a baseline for climate-change projections. To date, paleoclimate records have seen limited engineering use to estimate hydrologic risks because water systems models and managers usually require streamflow input at the monthly scale. This study explores the hypothesis that monthly streamflows can be adequately modeled by statistically decomposing annual flow reconstructions. To test this hypothesis, a multiple linear regression model for monthly streamflow reconstruction is presented that expands the set of predictors to include annual streamflow reconstructions, …

Propeller Design Requirements For Quadcopters Utilizing Variable Pitch Propellers, Ian R. Mcandrew, Elena Navarro, Ken Witcher

Publications

Unmanned aerial vehicles, UAV, has increases in the drastically in these past several years since their costs reduced. This research is based and built upon previous research presented in a conference. With the advent of commercial Quadcopters, four propeller systems, are used, being designed and used to operate the advantages of both flight and hovering. The basic design of their propeller blades has not evolved from the early days of manned flight when wooden fixed blades were used. In this paper that expands upon previous findings and discussions it explores the historical developments. Furthermore, how the expansion and reduction in …

The Effects Of Isoprene And Nox On Secondary Organic Aerosols Formed Through Reversible And Irreversible Uptake To Aerosol Water, Marwa M. El-Sayed, Diana L. Ortiz-Montalvo, Christopher J. Hennigan

Publications

Isoprene oxidation produces water-soluble organic gases capable of partitioning to aerosol liquid water. The formation of secondary organic aerosols through such aqueous pathways (aqSOA) can take place either reversibly or irreversibly; however, the split between these fractions in the atmosphere is highly uncertain. The aim of this study was to characterize the reversibility of aqSOA formed from isoprene at a location in the eastern United States under substantial influence from both anthropogenic and biogenic emissions. The reversible and irreversible uptake of water-soluble organic gases to aerosol water was characterized in Baltimore, Maryland, USA, using measurements of particulate water-soluble organic carbon …

Godunov-Type Upwind Flux Schemes Of The Two-Dimensional Finite Volume Discrete Boltzmann Method, Leitao Chen, Laura Schaefer

Publications

A simple unified Godunov-type upwind approach that does not need Riemann solvers for the flux calculation is developed for the finite volume discrete Boltzmann method (FVDBM) on an unstructured cell-centered triangular mesh. With piecewise-constant (PC), piecewise-linear (PL) and piecewise-parabolic (PP) reconstructions, three Godunov-type upwind flux schemes with different orders of accuracy are subsequently derived. After developing both a semi-implicit time marching scheme tailored for the developed flux schemes, and a versatile boundary treatment that is compatible with all of the flux schemes presented in this paper, numerical tests are conducted on spatial accuracy for several single-phase flow problems. Four major …

First Search For Nontensorial Gravitational Waves From Known Pulsars, B. P. Abbott, K. Aultoneal, S. Gaudio, K. Gill, B. Hughey, J. W. W. Pratt, E. Schmidt, S. G. Schwalbe, M. J. Szczepańczyk, M. Zanolin, Et Al.

Publications

We present results from the first directed search for nontensorial gravitational waves. While general relativity allows for tensorial (plus and cross) modes only, a generic metric theory may, in principle, predict waves with up to six different polarizations. This analysis is sensitive to continuous signals of scalar, vector, or tensor polarizations, and does not rely on any specific theory of gravity. After searching data from the first observation run of the advanced LIGO detectors for signals at twice the rotational frequency of 200 known pulsars, we find no evidence of gravitational waves of any polarization. We report the first upper …

Mechanical And Electrical Characterization Of Carbon Fiber/Bucky Paper/Zinc Oxide Hybrid Composites, Suma Ayyagari, Marwan Al-Haik, Virginie Rollin

Publications

The quest for multifunctional carbon fiber reinforced composites (CFRPs) expedited the use of several nano reinforcements such as zinc oxide nanorods (ZnO) and carbon nanotubes (CNTs). Zinc oxide is a semi-conductor with good piezoelectric and pyroelectric properties. These properties could be transmitted to CFRPs when a nanophase of ZnO is embedded within CFRPs. In lieu of ZnO nanorods, Bucky paper comprising mat of CNTs could be sandwiched in-between composite laminae to construct a functionally graded composite with enhanced electrical conductivities. In this study, different configurations of hybrid composites based on carbon fibers with different combinations of ZnO nanorods and Bucky …

Computer Program, System, And Method For Observation And Communication For Mobile Settings, Mobile Applications, And Wearable Mobile Devices, Jibo He, Barbara Chaparro

Publications

A system including at least first and second wearable mobile devices and optionally one or more smartphones or other computing devices for allowing a wearable mobile device wearer, an on-site observer, and a remote observer to research and test usability of products in mobile settings, mobile applications, mobile devices, and wearable mobile devices, desktop usability settings, and other settings and devices. The devices nm a software application for generating first-person video and third-person video, transmitting the video to the other devices, marking the videos with time stamps, and allowing the remote observer to send messages and other information to the …

Ten Years Of The Real World Design Challenge, Robert W. Deters, Brent Terwilliger, S.C. Kleinke, Ralph K. Coppola, Jeff Coppola

Publications

Preparing students to be successful in STEM careers is important to foster continued growth in the US and the world. The Real World Design Challenge is a high school design competition focused on the area of aviation. Students work in teams to solve a real world problem using professional tools. The 2018 challenge marks the tenth anniversary of this program. The first students to compete in this competition are now in the work force. This paper describes the background of RWDC, the different challenges that have been used throughout its ten years, the current precision agriculture challenges using UAS, and …

Unmanned Aerial Systems: Research, Development, Education & Training At Embry-Riddle Aeronautical University, Michael P. Hickey

Publications

With technological breakthroughs in miniaturized aircraft-related components, including but not limited to communications, computer systems and sensors, state-of-the-art unmanned aerial systems (UAS) have become a reality. This fast-growing industry is anticipating and responding to a myriad of societal applications that will provide new and more cost-effective solutions that previous technologies could not, or will replace activities that involved humans in flight with associated risks.

Embry-Riddle Aeronautical University has a long history of aviation-related research and education, and is heavily engaged in UAS activities. This document provides a summary of these activities, and is divided into two parts. The first part …

Which Neuropsychological Functions Predict Various Processing Speed Components In Children With And Without Attention-Deficit/Hyperactivity Disorder?, Sarah A Vadnais, Michelle Y Kibby, Audreyana C Jagger-Rickels

Publications

We identified statistical predictors of four processing speed (PS) components in a sample of 151 children with and without attention-deficit/hyperactivity disorder (ADHD). Performance on perceptual speed was predicted by visual attention/short-term memory, whereas incidental learning/psychomotor speed was predicted by verbal working memory. Rapid naming was predictive of each PS component assessed, and inhibition predicted all but one task, suggesting a shared need to identify/retrieve stimuli rapidly and inhibit incorrect responding across PS components. Hence, we found both shared and unique predictors of perceptual, cognitive, and output speed, suggesting more specific terminology should be used in future research on PS in …

Increased Overwinter Mortalities Of White-Tailed Deer (Odocoileus Virginianus) Fawns During A Drought Year, Marie I. Tosa, Matthew Thomas Springer, Clayton Nielsen, Eric M. Schauber

Publications

Mortality rates of white-tailed deer (Odocoileus virginianus (Zimmerman, 1780)) fawns have been quantified throughout North America. Few studies, however, have assessed cause-specific mortality of fawns after the first 3 months of life or during a severe weather event. During 2010-2014, we captured and radiotracked 93 fawns in southern and central Illinois and recorded 18 mortality events. In order of importance, survival rates were affected by days since capture, year of drought, age at capture, week post-capture (1/0 indicator), and region. Estimated overwinter (fall through spring) survival rate (± SE) of fawns in both regions during 2010-14 was 0.83 ± …

Supporting Elementary Teachers’ Enactment Of Nature Of Science Instruction: A Randomized Controlled Trial, Jennifer L. Maeng, Randy L. Bell, Tyler St. Clair, Amanda L. Gonczi, Brooke A. Whitworth

Publications

This embedded mixed method study used a randomised controlled⁠ trial design to examine two cohorts of upper (grades 4–6) elementary teachers’ classroom implementation of nature of science (NOS) instruction following their participation in a statewide professional development (PD). The treatment group (n = 145) was compared to a control group (n = 90), which received no PD. The PD included a summer institute that situated explicit NOS instruction within the context of problem-based learning (PBL). Data sources included videotaped classroom observations across four time points and teacher-generated descriptions of lessons preceding and following the observed lesson including learning …

A Complementary Cyber-Human Systems Framework For Industry 4.0 Cyber-Physical Systems, Matthew Krugh, Laine Mears

Publications

Humans are a vital element to automotive manufacturing; however, skilled production personnel have largely been designated as data receivers in Cyber-Physical Systems (CPS) of Industry 4.0. A renewed focus on the human worker who completes significant portions of manual value-added content in automotive assembly through Cyber-Human Systems (CHS) is allowing humans to perform their jobs more safely, efficiently, and supporting enhanced control and quality monitoring of manual manufacturing tasks. There is a need for a unified complementary framework of CHS and CPS to guide the implementation of future smart manufacturing systems.

Jane Jacobs And Dark Age America, Peter L. Laurence

Publications

No abstract provided.

Cardiovascular Biomechanical Models, Ethan Kung

Publications

Computational and in vitro methods offer powerful means to model the cardiovascular system and investigate biomechanics related to blood flow, cardiovascular tissue, and medical devices. These models can be constructed to directly describe human anatomy and physiology, and can be more highly controlled compared to animal models. Low-order models composed of lumped-parameter elements and simplified descriptions of cardiac function can capture the global physiology, while high-order models exhibiting detailed 3D anatomy and dynamics can provide highly realistic replication of biomechanical interactions in a small region of the circulation. Multiscale models offer the freedom to capture biomechanics in different regions at …

Which Neuropsychological Functions Predict Various Processing Speed Components In Children With And Without Attention-Deficit/Hyperactivity Disorder?, Sarah A Vadnais, Michelle Y Kibby, Audreyana C Jagger-Rickels

Publications

We identified statistical predictors of four processing speed (PS) components in a sample of 151 children with and without attention-deficit/hyperactivity disorder (ADHD). Performance on perceptual speed was predicted by visual attention/short-term memory, whereas incidental learning/psychomotor speed was predicted by verbal working memory. Rapid naming was predictive of each PS component assessed, and inhibition predicted all but one task, suggesting a shared need to identify/retrieve stimuli rapidly and inhibit incorrect responding across PS components. Hence, we found both shared and unique predictors of perceptual, cognitive, and output speed, suggesting more specific terminology should be used in future research on PS in …

Which Neuropsychological Functions Predict Various Processing Speed Components In Children With And Without Attention-Deficit/Hyperactivity Disorder?, Sarah A Vadnais, Michelle Y Kibby, Audreyana C Jagger-Rickels

Publications

We identified statistical predictors of four processing speed (PS) components in a sample of 151 children with and without attention-deficit/hyperactivity disorder (ADHD). Performance on perceptual speed was predicted by visual attention/short-term memory, whereas incidental learning/psychomotor speed was predicted by verbal working memory. Rapid naming was predictive of each PS component assessed, and inhibition predicted all but one task, suggesting a shared need to identify/retrieve stimuli rapidly and inhibit incorrect responding across PS components. Hence, we found both shared and unique predictors of perceptual, cognitive, and output speed, suggesting more specific terminology should be used in future research on PS in …

Extensive Crispr Rna Modification Reveals Chemical Compatibility And Structure-Activity Relationships For Cas9 Biochemical Activity, Keith T. Gagnon

Publications

CRISPR (clustered regularly interspaced short palindromic repeat) endonucleases are at the forefront of biotechnology, synthetic biology and gene editing. Methods for controlling enzyme properties promise to improve existing applications and enable new technologies. CRISPR enzymes rely on RNA cofactors to guide catalysis. Therefore, chemical modification of the guide RNA can be used to characterize structure-activity relationships within CRISPR ribonucleoprotein (RNP) enzymes and identify compatible chemistries for controlling activity. Here, we introduce chemical modifications to the sugar-phosphate backbone of Streptococcus pyogenes Cas9 CRISPR RNA (crRNA) to probe chemical and structural requirements. Ribose sugars that promoted or accommodated A-form helical architecture in …

Feeding The Eco-Consumer, Alexia Brunet Marks

Publications

There is a lot of talk about making our food system more “sustainable,” and eco-consumers — those who consider environmental sustainability as an important purchasing priority — are making themselves heard. This growing consumer segment is rapidly gaining national attention for moving more sustainable products to the market, and for its willingness to pay more for these options. However, while economists normally predict that higher prices lead profit-minded suppliers to enter a market to meet a new and growing demand, this transition is not occurring at the pace one would expect.

This Article argues that land tenure status — whether …