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2020

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Articles 38131 - 38160 of 39223

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Wheat Growth Monitoring And Yield Estimation Based On Multi-Rotor Unmanned Aerial Vehicle, Zhaopeng Fu, Jie Jang, Yang Gao, Brian Krienke, Meng Wang, Kaitai Zhong, Qiang Cao, Yongchao Tian, Yan Zhu, Weixing Cao, Xiaojun Liu Jan 2020

Wheat Growth Monitoring And Yield Estimation Based On Multi-Rotor Unmanned Aerial Vehicle, Zhaopeng Fu, Jie Jang, Yang Gao, Brian Krienke, Meng Wang, Kaitai Zhong, Qiang Cao, Yongchao Tian, Yan Zhu, Weixing Cao, Xiaojun Liu

Department of Agronomy and Horticulture: Faculty Publications

Leaf area index (LAI) and leaf dry matter (LDM) are important indices of crop growth. Real-time, nondestructive monitoring of crop growth is instructive for the diagnosis of crop growth and prediction of grain yield. Unmanned aerial vehicle (UAV)-based remote sensing is widely used in precision agriculture due to its unique advantages in flexibility and resolution. This study was carried out on wheat trials treated with different nitrogen levels and seeding densities in three regions of Jiangsu Province in 2018–2019. Canopy spectral images were collected by the UAV equipped with a multi-spectral camera during key wheat growth stages. To verify the …

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The State Of Sustainable Agriculture And Agroecology Research And Impacts: A Survey Of U.S. Scientists, Marcia Delonge, Tali Robbins, Andrea D. Basche, Lindsey Haynes-Maslow Jan 2020

The State Of Sustainable Agriculture And Agroecology Research And Impacts: A Survey Of U.S. Scientists, Marcia Delonge, Tali Robbins, Andrea D. Basche, Lindsey Haynes-Maslow

Department of Agronomy and Horticulture: Faculty Publications

A growing body of research suggests that although sustainable agriculture, particularly agroecology, can address challenges such as those related to climate change, ecosystem services, food insecurity, and farmer livelihoods, the transition to such systems remains limited. To gain insight into the state of U.S. sustainable agriculture and agroecology, we developed a 28-question mixed-method survey that was administered to scientists in these fields. Respondents (N=168) represented diverse locations, institutions, and career stages. They offered varied definitions of sustainable agriculture, with 40% considering economic and social well-being to be core components. Respondents identified the amount and duration of public research …

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Dicamba Retention In Commercial Sprayers Following Triple Rinse Cleanout Procedures, And Soybean Response To Contamination Concentrations, Frances B. Browne, Xiao Li, Katilyn J. Price, Jianping Wang, Yi Wang, Greg R. Kruger, Jeff Golus, Gabrielle De Castro Macedo, Bruno C. Vieira, Tyler Sandlin Jan 2020

Dicamba Retention In Commercial Sprayers Following Triple Rinse Cleanout Procedures, And Soybean Response To Contamination Concentrations, Frances B. Browne, Xiao Li, Katilyn J. Price, Jianping Wang, Yi Wang, Greg R. Kruger, Jeff Golus, Gabrielle De Castro Macedo, Bruno C. Vieira, Tyler Sandlin

Department of Agronomy and Horticulture: Faculty Publications

The commercial launch of dicamba‐tolerant (DT) crops has resulted in increased dicamba usage and a high number of dicamba off‐target movement complaints on sensitive soybeans (Glycine max L.). Dicamba is a synthetic auxin and low dosages as 0.028 g ae ha−1 can induce injury on sensitive soybean. Tank contamination has been identified as one of the sources for unintended sensitive crop exposure. The labels of new dicamba formulations require a triple rinse cleanout procedure following applications. Cleanout efficacy might vary based on the sprayer type and procedure followed. This study was performed to quantify dicamba retention in commercial sprayers and …

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Investigation Of Emotional Intelligence And Computer Self-Efficacy On The Cybersecurity Interest Of High School Students, William Earl Hilliker Jr. Jan 2020

Investigation Of Emotional Intelligence And Computer Self-Efficacy On The Cybersecurity Interest Of High School Students, William Earl Hilliker Jr.

Master's Theses and Doctoral Dissertations

There is a lack of interest in young students in pursuing a career in cybersecurity. Defining potential traits that could identify an interested student could help fill the national shortage of cybersecurity professionals. This study examines the relationship between computer self-efficacy, emotional intelligence, and an interest in a cybersecurity career of high school students in Southeast Michigan. It also attempts to determine if a student’s participation in STEM events and the location of the student’s school are significant moderating factors. A cross-sectional survey was conducted on a sample of 280 students in Grades 9 through 12 who attended school at …

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Winter Cover Crop Root Biomass Yield In Corn And Soybean Systems, Sabrina J. Ruis, Humberto Blanco-Canqui, Katja Koehler-Cole, Paul J. Jasa, G. Slater, Roger W. Elmore, Richard B. Ferguson Jan 2020

Winter Cover Crop Root Biomass Yield In Corn And Soybean Systems, Sabrina J. Ruis, Humberto Blanco-Canqui, Katja Koehler-Cole, Paul J. Jasa, G. Slater, Roger W. Elmore, Richard B. Ferguson

Department of Agronomy and Horticulture: Faculty Publications

Cover crop (CC) roots are critical for soil ecosystem service delivery including soil stabilization, C and nutrient cycling, soil health improvement, and others. However, most CC studies only evaluate CC aboveground biomass yield, neglecting the belowground portion of the plant. The objectives of this study were to quantify the impacts of (a) CC planting (pre- and post-harvest) dates and (b) early (2–4 wk before main crop planting) and late (at main crop planting) CC termination with and without corn (Zea mays L.) residue removal on root biomass yield. We assessed the effects of CC planting or termination dates on root …

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The Lateral Root Density Gene Regulates Root Growth During Water Stress In Wheat, Dante F. Placido, Jaspreet Sandhu, Shirley Sato, Natalya Nersesian, Truyen Quach, Thomas Clemente, Paul Staswick, Harkamal Walia Jan 2020

The Lateral Root Density Gene Regulates Root Growth During Water Stress In Wheat, Dante F. Placido, Jaspreet Sandhu, Shirley Sato, Natalya Nersesian, Truyen Quach, Thomas Clemente, Paul Staswick, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Drought stress is the major limiting factor in agriculture. Wheat, which is the most widely grown crop in the world, is predominantly cultivated in drought-prone rainfed environments. Since roots play a critical role in water uptake, root response to water limitations is an important component for enhancing wheat adaptation. In an effort to discover novel genetic sources for improving wheat adaptation, we characterized a wheat translocation line with a chromosomal segment from Agropyron elongatum, a wild relative of wheat, which unlike common wheat maintains root growth under limited-water conditions. By exploring the root transcriptome data, we found that reduced …

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Spatial Particulate Fields During Highwinds In The Imperial Valley, California, Frank R. Freedman, Paul English, Jeff Wagner, Yang Liu, Akula Venkatram, Daniel Q. Tong, Mohammad Z. Al-Hamdan, Meytar Sorek-Hamer, Robert Chatfield, Ana Rivera, Patrick L. Kinney Jan 2020

Spatial Particulate Fields During Highwinds In The Imperial Valley, California, Frank R. Freedman, Paul English, Jeff Wagner, Yang Liu, Akula Venkatram, Daniel Q. Tong, Mohammad Z. Al-Hamdan, Meytar Sorek-Hamer, Robert Chatfield, Ana Rivera, Patrick L. Kinney

Faculty Research, Scholarly, and Creative Activity

We examined windblown dust within the Imperial Valley (CA) during strong springtime west-southwesterly (WSW) wind events. Analysis of routine agency meteorological and ambient particulate matter (PM) measurements identified 165 high WSW wind events between March and June 2013 to 2019. The PM concentrations over these days are higher at northern valley monitoring sites, with daily PM mass concentration of particles less than 10 micrometers aerodynamic diameter (PM10) at these sites commonly greater than 100 μg/m3 and reaching around 400 μg/m3, and daily PM mass concentration of particles less than 2.5 micrometers aerodynamic diameter (PM2.5) commonly greater than 20 μg/m3 and …

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Electromagnetic-Circuital-Thermal Multiphysics Simulation Method: A Review, Huan Huan Zhang, Pan Pan Wang, Shuai Zhang, Long Li, Ping Li, Wei E.I. Sha, Li (Lijun) Jun Jiang Jan 2020

Electromagnetic-Circuital-Thermal Multiphysics Simulation Method: A Review, Huan Huan Zhang, Pan Pan Wang, Shuai Zhang, Long Li, Ping Li, Wei E.I. Sha, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

Electromagnetic-circuital-thermal multiphysics simulation is a very important topic in the field of integrated circuits (ICs), microwave circuits, antennas, etc. This paper presents a comprehensive review of the state of the art of electromagnetic-circuital-thermal multiphysics simulation method. Most efforts were focused on electromagnetic-circuital co-simulation and electromagnetic-thermal cosimulation. A brief introduction of related theories like governing equations, numerical methods, and coupling mechanisms is also included.

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Crowdsourcing Contests: Understanding The Effect Of Environment And Organization Specific Factors On Sustained Participation, Hanieh Javadi Khasraghi, Xuan Wang Jan 2020

Crowdsourcing Contests: Understanding The Effect Of Environment And Organization Specific Factors On Sustained Participation, Hanieh Javadi Khasraghi, Xuan Wang

Information Systems Faculty Publications

Crowdsourcing has increasingly become a recognized problem-solving mechanism for organizations by outsourcing the problem to an undefined crowd of people. The success of crowdsourcing depends on the sustained participation and quality-submissions of the individuals. Yet, little is known about the environment-specific and organization-specific factors that influence individuals’ continued participation in these contests. We address this research gap, by conducting an empirical study using data from an online crowdsourcing contest platform, Kaggle, which delivers data science and machine learning solutions to its clients. The findings show the statistically significant effects of structural capital, familiarity with organization, and experience with the organization …

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Numerical Methods For Electromagnetic Modeling Of Graphene: A Review, Kaikun Niu, Ping Li, Zhixiang Huang, Li (Lijun) Jun Jiang, Hakan Bagci Jan 2020

Numerical Methods For Electromagnetic Modeling Of Graphene: A Review, Kaikun Niu, Ping Li, Zhixiang Huang, Li (Lijun) Jun Jiang, Hakan Bagci

Electrical and Computer Engineering Faculty Research & Creative Works

Graphene's remarkable electrical, mechanical, thermal, and chemical properties have made this the frontier of many other 2-D materials a focus of significant research interest in the last decade. Many theoretical studies of the physical mechanisms behind these properties have been followed by those investing the graphene's practical use in various fields of engineering. Electromagnetics, optics, and photonics are among these fields, where potential benefits of graphene in improving the device/system performance have been studied. These studies are often carried out using simulation tools. To this end, many numerical methods have been developed to characterize electromagnetic field/wave interactions on graphene sheets …

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Predicting Densities And Elastic Moduli Of Sio2-Based Glasses By Machine Learning, Yong-Jie Hu, Ge Zhao, Mingfei Zhang, Bin Bin, Tyler Del Rose, Qian Zhao, Qan Zu, Yang Chen, Xuekun Sun, Maarten De Jong, Multiple Additional Authors Jan 2020

Predicting Densities And Elastic Moduli Of Sio2-Based Glasses By Machine Learning, Yong-Jie Hu, Ge Zhao, Mingfei Zhang, Bin Bin, Tyler Del Rose, Qian Zhao, Qan Zu, Yang Chen, Xuekun Sun, Maarten De Jong, Multiple Additional Authors

Mathematics and Statistics Faculty Publications and Presentations

Chemical design of SiO2-based glasses with high elastic moduli and low weight is of great interest. However, it is difficult to find a universal expression to predict the elastic moduli according to the glass composition before synthesis since the elastic moduli are a complex function of interatomic bonds and their ordering at different length scales. Here we show that the densities and elastic moduli of SiO2-based glasses can be efficiently predicted by machine learning (ML) techniques across a complex compositional space with multiple (>10) types of additive oxides besides SiO2. Our machine learning approach relies on a training set …

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Assessing The Severity Of Health States Based On Social Media Posts, Shweta Yadav, Joy Prakash Sain, Amit P. Sheth, Asif Ekbal, Sriparna Saha, Pushpak Bhattacharyya Jan 2020

Assessing The Severity Of Health States Based On Social Media Posts, Shweta Yadav, Joy Prakash Sain, Amit P. Sheth, Asif Ekbal, Sriparna Saha, Pushpak Bhattacharyya

Publications

The unprecedented growth of Internet users has resulted in an abundance of unstructured information on social media including health forums, where patients request healthrelated information or opinions from other users. Previous studies have shown that online peer support has limited effectiveness without expert intervention. Therefore, a system capable of assessing the severity of health state from the patients’ social media posts can help health professionals (HP) in prioritizing the user’s post. In this study, we inspect the efficacy of different aspects of Natural Language Understanding (NLU) to identify the severity of the user’s health state in relation to two perspectives(tasks) …

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Automatic Target Recognition With Deep Metric Learning., Abdelhamid Bouzid Jan 2020

Automatic Target Recognition With Deep Metric Learning., Abdelhamid Bouzid

Electronic Theses and Dissertations

An Automatic Target Recognizer (ATR) is a real or near-real time understanding system where its input (images, signals) are obtained from sensors and its output is the detected and recognized target. ATR is an important task in many civilian and military computer vision applications. The used sensors, such as infrared (IR) imagery, enlarge our knowledge of the surrounding environment, especially at night as they provide continuous surveillance. However, ATR based on IR faces major challenges such as meteorological conditions, scale and viewpoint invariance. In this thesis, we propose solutions that are based on Deep Metric Learning (DML). DML is a …

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Alone: A Dataset For Toxic Behavior Among Adolescents On Twitter, Thilini Wijesiriwardene, Hale Inan, Ugur Kursuncu, Manas Gaur, Valerie L. Shalin, Krishnaprasad Thirunarayan, Amit P. Sheth, I. Budak Arpinar Jan 2020

Alone: A Dataset For Toxic Behavior Among Adolescents On Twitter, Thilini Wijesiriwardene, Hale Inan, Ugur Kursuncu, Manas Gaur, Valerie L. Shalin, Krishnaprasad Thirunarayan, Amit P. Sheth, I. Budak Arpinar

Publications

The convenience of social media has also enabled its misuse, potentially resulting in toxic behavior. Nearly 66% of internet users have observed online harassment, and 41% claim personal experience, with 18% facing severe forms of online harassment. This toxic communication has a significant impact on the well-being of young individuals, affecting mental health and, in some cases, resulting in suicide. These communications exhibit complex linguistic and contextual characteristics, making recognition of such narratives challenging. In this paper, we provide a multimodal dataset of toxic social media interactions between confirmed high school students, called ALONE (AdoLescents ON twittEr), along with descriptive …

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Measurement Of Sub-2 Nm Stable Clusters During Silane Pyrolysis In A Furnace Aerosol Reactor, Miguel Vazquez-Pufleau, Yang Wang, Pratim Biswas, Elijah Thimsen Jan 2020

Measurement Of Sub-2 Nm Stable Clusters During Silane Pyrolysis In A Furnace Aerosol Reactor, Miguel Vazquez-Pufleau, Yang Wang, Pratim Biswas, Elijah Thimsen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The initial stages of particle formation are important in several industrial and environmental systems; however, the phenomenon is not completely understood due to the inability to measure cluster size distributions. A high resolution differential mobility analyzer with an electrometer was used to map out the early stages of Si particle formation from pyrolysis of SiH4 in a furnace aerosol reactor. We detected for the first time subnanometer stable clusters from silane pyrolysis, and the diameter was measured to be about 0.7 nm. This diameter is within the range of probable sizes that the reported families of critical silane clusters could …

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Bending Behavior And Deflection Prediction Of High-Strength Sfrc Beams Under Fatigue Loading, Dan Ying Gao, Zhi Qiang Gu, Chenglin Wu Jan 2020

Bending Behavior And Deflection Prediction Of High-Strength Sfrc Beams Under Fatigue Loading, Dan Ying Gao, Zhi Qiang Gu, Chenglin Wu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The experiments of high-strength steel-fiber-reinforced concrete (SFRC) beams subjected to fatigue bend loading were conducted in this work. A total of 12 beams were tested to failure, including 2 under static loading and 10 under fatigue loading. The main varying parameters of the tested beams included the stress level, fiber volume fraction, and strength of the steel reinforcement. The fatigue life, mid-span deflection, residual deflection, and crack width were measured and evaluated. The stiffness degradation of high-strength SFRC beams was analyzed. The results indicated that both the stress level and fiber volume fraction have significant influences on the fatigue life …

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Special Section Guest Editorial: Machine Learning In Optics, Jonathan Howe, Travis Axtell, Khan Iftekharuddin Jan 2020

Special Section Guest Editorial: Machine Learning In Optics, Jonathan Howe, Travis Axtell, Khan Iftekharuddin

Electrical & Computer Engineering Faculty Publications

This guest editorial summarizes the Special Section on Machine Learning in Optics.

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Real-Time Optimization Of Anti-Reflective Coatings For Cigs Solar Cells, Grace Rajan, Shankar Karki, Robert W. Collins, Nikolas J. Podraza, Sylvain Marsillac Jan 2020

Real-Time Optimization Of Anti-Reflective Coatings For Cigs Solar Cells, Grace Rajan, Shankar Karki, Robert W. Collins, Nikolas J. Podraza, Sylvain Marsillac

Electrical & Computer Engineering Faculty Publications

A new method combining in-situ real-time spectroscopic ellipsometry and optical modeling to optimize the thickness of an anti-reflective (AR) coating for Cu(In,Ga)Se2 (CIGS) solar cells is described and applied directly to fabricate devices. The model is based on transfer matrix theory with input from the accurate measurement of complex dielectric function spectra and thickness of each layer in the solar cell by spectroscopic ellipsometry. The AR coating thickness is optimized in real time to optically enhance device performance with varying thickness and properties of the constituent layers. Among the parameters studied, we notably demonstrate how changes in thickness of …

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Assessing If Motivation Impacts General Aviation Pilots’ Persistence In Varying Weather Conditions, Sabrina Woods Jan 2020

Assessing If Motivation Impacts General Aviation Pilots’ Persistence In Varying Weather Conditions, Sabrina Woods

Doctoral Dissertations and Master's Theses

Continued flight under visual flight rules into instrument meteorological conditions is the predominant cause for fatal accidents by percentage, for general aviation aircraft operations. It is possible that a pilot’s motivation or reason for flying will override other safer, more logical courses of action when a hazard presents itself. The decision appears to stem from a willingness to persist in a course of action despite factors that indicate an alternate and safer course is warranted. This research addresses what is currently presumed about the decision to continue flying under visual flight rules into instrument conditions and marries those ideas with …

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Methodology For Quantifying Resiliency Of Transportation Systems, Hannah Rose Russell Jan 2020

Methodology For Quantifying Resiliency Of Transportation Systems, Hannah Rose Russell

Doctoral Dissertations and Master's Theses

The National Science Foundation’s definition of resiliency is “the ability to prepare and plan for, absorb, recover from, or more successfully adapt to actual or potential adverse events” (National Science Foundation, 2016). While this definition is informative and useful, it lacks a quantitative reference. There is a need for a method of quantifying resilience to better plan and prepare for system wide disruptions. The research effort described herein provides a quantifiable measures of system resiliency, consistent with NSF’s definition. Fundamentally, a system disruption can be partitioned into five distinctive states: the stable pre-event state, the absorption state, the disrupted state, …

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Redefining Creep: A Comprehensive Analysis Of Aviation Accident Survivability, Michael Knott Jan 2020

Redefining Creep: A Comprehensive Analysis Of Aviation Accident Survivability, Michael Knott

Doctoral Dissertations and Master's Theses

Given the sheer amount of flights that occur on a daily basis around the world, aviation accidents are going to occur. The principles ensuring that an accident is as safe as possible are considered aircraft survivability or crashworthiness which is analyzed using the acronym CREEP; Container, Restraint, Environment, Energy Absorption, and Post-Crash Factors. CREEP is used by investigators to analyze survivability after a crash, but has significant short falls. By only focusing on a crash, CREEP misses several survivability concepts applicable to aviation such as aircraft equipped with ejection seats, inflight environmental factors, and high …

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Minding Morality: Ethical Artificial Societies For Public Policy Modeling, Saikou Y. Diallo, F. Leron Shults, Wesley J. Wildman Jan 2020

Minding Morality: Ethical Artificial Societies For Public Policy Modeling, Saikou Y. Diallo, F. Leron Shults, Wesley J. Wildman

VMASC Publications

Public policies are designed to have an impact on particular societies, yet policy-oriented computer models and simulations often focus more on articulating the policies to be applied than on realistically rendering the cultural dynamics of the target society. This approach can lead to policy assessments that ignore crucial social contextual factors. For example, by leaving out distinctive moral and normative dimensions of cultural contexts in artificial societies, estimations of downstream policy effectiveness fail to account for dynamics that are fundamental in human life and central to many public policy challenges. In this paper, we supply evidence that incorporating morally salient …

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Security In 5g-Enabled Internet Of Things Communication: Issues: Challenges, And Future Research Roadmap, Mohammad Wazid, Ashok Kumar Das, Sachin Shetty, Prosanta Gope, Joel J.P.C. Rodrigues Jan 2020

Security In 5g-Enabled Internet Of Things Communication: Issues: Challenges, And Future Research Roadmap, Mohammad Wazid, Ashok Kumar Das, Sachin Shetty, Prosanta Gope, Joel J.P.C. Rodrigues

VMASC Publications

5G mobile communication systems promote the mobile network to not only interconnect people, but also interconnect and control the machine and other devices. 5G-enabled Internet of Things (IoT) communication environment supports a wide-variety of applications, such as remote surgery, self-driving car, virtual reality, flying IoT drones, security and surveillance and many more. These applications help and assist the routine works of the community. In such communication environment, all the devices and users communicate through the Internet. Therefore, this communication agonizes from different types of security and privacy issues. It is also vulnerable to different types of possible attacks (for example, …

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The Artificial University: Decision Support For Universities In The Covid-19 Era, Wesley J. Wildman, Saikou Y. Diallo, George Hodulik, Andrew Page, Andreas Tolk, Neha Gondal Jan 2020

The Artificial University: Decision Support For Universities In The Covid-19 Era, Wesley J. Wildman, Saikou Y. Diallo, George Hodulik, Andrew Page, Andreas Tolk, Neha Gondal

VMASC Publications

Operating universities under pandemic conditions is a complex undertaking. The Artificial University (TAU) responds to this need. TAU is a configurable, open-source computer simulation of a university using a contact network based on publicly available information about university classes, residences, and activities. This study evaluates health outcomes for an array of interventions and testing protocols in an artificial university of 6,500 students, faculty, and staff. Findings suggest that physical distancing and centralized contact tracing are most effective at reducing infections, but there is a tipping point for compliance below which physical distancing is less effective. If student compliance is anything …

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Post-Supernatural Cultures: There And Back Again, Wesley J. Wildman, F. Leron Shults, Saikou Y. Diallo, Ross Gore, Justin Lane Jan 2020

Post-Supernatural Cultures: There And Back Again, Wesley J. Wildman, F. Leron Shults, Saikou Y. Diallo, Ross Gore, Justin Lane

VMASC Publications

The abandonment of supernatural religious beliefs and rituals seems to occur quite easily in some contexts, but post-supernaturalist cultures require a specific set of conditions that are difficult to produce and sustain on a large scale and thus are historically rare. Despite the worldwide resurgence of supernaturalist religion, some subcultures reliably produce people who deny the existence of supernatural entities. This social phenomenon has evoked competing explanations, many of which enjoy empirical support. We synthesize six of the most influential social-science explanations, demonstrating that they provide complementary perspectives on a complex causal architecture. We incorporate this theoretical synthesis into a …

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Impact Of Considering And Neglecting States On Descent-To-Landing Navigation, Kyle J. Demars, Kari C. Ward Jan 2020

Impact Of Considering And Neglecting States On Descent-To-Landing Navigation, Kyle J. Demars, Kari C. Ward

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper develops a novel square-root formulation of the consider/neglect Kalman filter for navigation applications. The proposed filter partitions system parameters into three distinct categories: those to be estimated by the filter, those whose contribution to the system can be considered without explicitly estimating them, and those with sufficiently low effect on the system such that their contribution can be neglected altogether. Discussion on appropriate selection of consider and neglect parameters is provided with specific attention given to descent-to-landing navigation. Monte Carlo simulations and analysis are performed to assess the performance of the square-root consider/neglect filter.

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Design And Analysis Of Descent-To-Landing Navigation Incorporating Terrain Effects, Kari C. Ward, Gunner S. Fritsch, J. Cameron Helmuth, Kyle J. Demars, James S. Mccabe Jan 2020

Design And Analysis Of Descent-To-Landing Navigation Incorporating Terrain Effects, Kari C. Ward, Gunner S. Fritsch, J. Cameron Helmuth, Kyle J. Demars, James S. Mccabe

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This study investigated the ability of a navigation filter to process multiple terrain-based sensors, such as slant-range, slant-speed, and terrain relative navigation sensors, during a descent-to-landing scenario to estimate the state of a landing vehicle. The filtering technique leveraged was based upon a factorized form of the multiplicative extended Kalman filter, and terrain-based measurements were fused with star camera and inertial measurement unit sensor returns to estimate the position, velocity, and attitude of the landing vehicle. Monte Carlo simulations were carried out to assess the performance of the navigation filter along a lunar descent trajectory, as well as the consistency …

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Science, Diplomacy, And The Red Sea's Unique Coral Reef: It's Time For Action, Karine Kleinhaus, Ali Al-Sawalmih, Daniel J. Barshis, Amatzia Genin, Lola N. Grace, Ove Hoegh-Guldberg, Yossi Loya, Anders Meiborn, Eslam O. Osman, Jean-Daniel Ruch, Yonathan Shaked, Christian R. Voolstra, Assaf Zvuloni, Maoz Fine Jan 2020

Science, Diplomacy, And The Red Sea's Unique Coral Reef: It's Time For Action, Karine Kleinhaus, Ali Al-Sawalmih, Daniel J. Barshis, Amatzia Genin, Lola N. Grace, Ove Hoegh-Guldberg, Yossi Loya, Anders Meiborn, Eslam O. Osman, Jean-Daniel Ruch, Yonathan Shaked, Christian R. Voolstra, Assaf Zvuloni, Maoz Fine

Biological Sciences Faculty Publications

Rapid ocean warming due to climate change poses a serious risk to the survival of coral reefs. It is estimated that 70–90 percent of all reefs will be severely degraded by mid-century even if the 1.5°C goal of the Paris Climate Agreement is achieved. However, one coral reef ecosystem seems to be more resilient to rising sea temperatures than most others. The Red Sea’s reef ecosystem is one of the longest continuous living reefs in the world, and its northernmost portion extends into the Gulf of Aqaba. The scleractinian corals in the Gulf have an unusually high tolerance for the …

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Correlates Of Bird Collisions With Buildings Across Three North American Countries, Jared A. Elmore, Stephen B. Hager, Bradley J. Cosentino, Nastasha Hagemeyer, Eric Walters, Scott R. Loss, Et Al. Jan 2020

Correlates Of Bird Collisions With Buildings Across Three North American Countries, Jared A. Elmore, Stephen B. Hager, Bradley J. Cosentino, Nastasha Hagemeyer, Eric Walters, Scott R. Loss, Et Al.

Biological Sciences Faculty Publications

Collisions with buildings cause up to 1 billion bird fatalities annually in North America. Bird-building collisions have recently received increased conservation, research, and policy attention. However, efforts to reduce collisions would benefit from studies conducted at large spatial scales across multiple study sites, with standardized methods, and with consideration of species- and life history-related variation and correlates of collisions. We addressed these research needs with a coordinated data collection effort at 40 sites across North America. We estimated collision vulnerability for 40 bird species by accounting for their North American population abundance, distribution overlap with study sites, and sampling effort. …

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Accuracy Of Predicted Energy Expenditure From A Fitbit Inspire Hr Activity Monitor During Short- And Long-Duration Exercise, Cailyn Van Camp Jan 2020

Accuracy Of Predicted Energy Expenditure From A Fitbit Inspire Hr Activity Monitor During Short- And Long-Duration Exercise, Cailyn Van Camp

Master's Theses and Doctoral Dissertations

PURPOSE: To determine the accuracy of predicted Energy Expenditure (EE) reported by a wrist-worn activity monitor compared to measured EE during both a long- and short-duration exercise. METHODS: In addition to a VO2max treadmill test, a running speed at approximately 70 - 75% of that VO2max was found during the first visit. The second and third visit was comprised of either a 30-minute or 10-minute run at the speed previously determined. A wrist activity monitor was worn and VO2 and EE were recorded by a metabolic cart. Pearson correlation, paired samples t-test, and repeated measures ANOVAs compared predicted …

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