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Articles 1 - 30 of 1954

Full-Text Articles in Physical Sciences and Mathematics

Water Efficiency & Sustainability In The Mountain West, 2022, Zachary Billot, Caitlin J. Saladino, William E. Brown Jr. Oct 2023

Water Efficiency & Sustainability In The Mountain West, 2022, Zachary Billot, Caitlin J. Saladino, William E. Brown Jr.

Environment

This fact sheet analyzes the effectiveness of state-level policies related to water usage, conservation, and sustainability for the Mountain West states of Arizona, Colorado, Nevada, New Mexico, and Utah in 2022. The original data are published in the “2022 State Policy Scorecard for Water Efficiency and Sustainability” report written by the Alliance for Water Efficiency.

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The High Pressure Dependence Of X-Ray Induced Decomposition Of Cadmium Oxalate, Adrian F. Lua Sanchez, Petrika Cifligu, Marc Graff, Michael Pravica, Pradip K. Bhowmik, Changyong Park, Egor Evlyukhin Oct 2023

The High Pressure Dependence Of X-Ray Induced Decomposition Of Cadmium Oxalate, Adrian F. Lua Sanchez, Petrika Cifligu, Marc Graff, Michael Pravica, Pradip K. Bhowmik, Changyong Park, Egor Evlyukhin

Physics & Astronomy Faculty Research

The high proclivity of x rays to destabilize and distort molecular structures has been previously utilized in the synthesis of novel compounds. Here, we show that x-ray induced decomposition of cadmium oxalate induces chemical and structural transformations only at 0.5 and 1 GPa. Using x-ray diffraction and Raman spectroscopy, the synthesized product is identified as cadmium carbonate with cadmium oxalate remnants, which is stable under ambient conditions. At ambient and >1 GPa pressures, only degradation of the electronic density distribution is observed. The transformation kinetics are examined in terms of Avrami’s model, which demonstrates that despite the necessity of high …

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Broadband Equity, Access, And Deployment In Nevada, Brad Wimmer Oct 2023

Broadband Equity, Access, And Deployment In Nevada, Brad Wimmer

Policy Briefs and Reports

The $45.45 billion Broadband, Equity, Access, and Deployment (BEAD) program’s primary objective is to extend broadband service to all unserved and underserved locations in the U.S. and its territories. Several industry studies predict that the BEAD program can meet its goal of providing universal access to broadband service if eligible entities execute their grant programs well. My review of the BEAD program indicates that policy makers can enhance the likelihood of program success by designing competitive grant programs that give applicants the incentive to undercut the subsidies proposed by their rivals and provide applicants the flexibility to design networks that …

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Environmental And Socio-Economic Stress In The Mountain West, Ayda Atici, Caitlin J. Saladino, Fatma Nasoz, William E. Brown Jr. Aug 2023

Environmental And Socio-Economic Stress In The Mountain West, Ayda Atici, Caitlin J. Saladino, Fatma Nasoz, William E. Brown Jr.

Environment

This fact sheet examines data on environmental and socio-economic risk metrics including which metrics pose the most risk for Nevada counties.The data are retrieved from “System for the Triage of Risks from Environmental and Socio-Economic Stressors” created by the Massachusetts Institute of Technology (MIT) joint program on the science and policy of global change.

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Coal Ash Dumps In The Mountain West, Julia Salangsang, Nicole Diaz Del Valle, Zachary Billot, Caitlin J. Saladino, William E. Brown Jr. Jul 2023

Coal Ash Dumps In The Mountain West, Julia Salangsang, Nicole Diaz Del Valle, Zachary Billot, Caitlin J. Saladino, William E. Brown Jr.

Environment

This fact sheet presents data on coal ash dumps, their management, and the pollutants that exist at each site in the Mountain West states of Arizona, Colorado, Nevada, New Mexico, and Utah. The original report includes data on coal ash dumping sites for all 50 states.

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The Climate Change Hope Scale: Does The Three-Factor Model Fit An Adult Sample?, Yuhan Bi, Victoria Angulo, Michal Newhouse-Van Vlerin, Orei Z. Odents, Kimberly A. Barchard Apr 2023

The Climate Change Hope Scale: Does The Three-Factor Model Fit An Adult Sample?, Yuhan Bi, Victoria Angulo, Michal Newhouse-Van Vlerin, Orei Z. Odents, Kimberly A. Barchard

Psychology Faculty Presentations

The Climate Change Hope Scale (CCHS; Li & Monroe, 2017) adapted Synder et al.'s (1991) Hope Scale to focus specifically on climate change. In an adolescent sample, the CCHS has three factors: Personal-sphere willpower and waypower, Collective-sphere willpower and waypower, and Lack of willpower and waypower. Our research tests if Li and Monroe's (2017) three-factor model fits the data from an adult sample.

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Electric Utility Performance In The Mountain West, Hira Ahmed, Miguel Soriano Ralston, Caitlin J. Saladino, William E. Brown Jr. Mar 2023

Electric Utility Performance In The Mountain West, Hira Ahmed, Miguel Soriano Ralston, Caitlin J. Saladino, William E. Brown Jr.

Environment

This fact sheet examines select data from the Citizens Utility Board (CUB) report, “Electric Utility Performance: A State-By-State Review,” which provides information on the affordability, reliability, and environmental responsibility of electric utility energy consumption. The original report provides a comprehensive state-by-state profile of utility performance in the United States. These data were originally reported by the Energy Information Administration (EIA) of the U.S. Department of Energy. This federal entity is responsible for the aggregation and dissemination of information about the American energy industry. This fact sheet highlights energy sources, affordability, reliability, and environmental impact of energy consumption in the Mountain …

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Recycling In The Mountain West, Zachary Billot, Caitlin J. Saladino, William E. Brown Jr. Mar 2023

Recycling In The Mountain West, Zachary Billot, Caitlin J. Saladino, William E. Brown Jr.

Environment

This fact sheet synthesizes data on rates of recycling from the March 2021 report "50 States of Recycling," sponsored by the Ball Corporation.The information presented in this document focuses on the effectiveness of recycling in total and by recyclable item, as well as the quantity of product recycled specifically within the Mountain West states of Arizona, Colorado, Nevada, New Mexico, and Utah.

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Drought Levels In Nevada Counties, 2022, Julianna Jovillar, Caitlin J. Saladino, William E. Brown Jr. Dec 2022

Drought Levels In Nevada Counties, 2022, Julianna Jovillar, Caitlin J. Saladino, William E. Brown Jr.

Environment

This fact sheet synthesizes data on drought levels within Nevada counties from the National Integrated Drought Information System (NIDIS) in 2022. The information presented in this document focuses on the breakdown of the number of Nevada residents affected by the droughts within each county and the drought experience in each county.

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How Dynamic Adsorption Controls Surfactant‑Enhanced Boiling, Mario R. Mata, Brandon Ortiz, Dhruv Luhar, Vesper Evereux, H. Jeremy Cho Oct 2022

How Dynamic Adsorption Controls Surfactant‑Enhanced Boiling, Mario R. Mata, Brandon Ortiz, Dhruv Luhar, Vesper Evereux, H. Jeremy Cho

Mechanical Engineering Faculty Research

No abstract provided.

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Beyond Functional Diversity: The Importance Of Trophic Position To Understanding Functional Processes In Community Evolution, Roxanne M. W. Banker, Ashley A. Dineen, Melanie G. Sorman, Carrie L. Tyler, Peter D. Roopnarine Oct 2022

Beyond Functional Diversity: The Importance Of Trophic Position To Understanding Functional Processes In Community Evolution, Roxanne M. W. Banker, Ashley A. Dineen, Melanie G. Sorman, Carrie L. Tyler, Peter D. Roopnarine

Geoscience Faculty Publications

Ecosystem structure—that is the species present, the functions they represent, and how those functions interact—is an important determinant of community stability. This in turn a􀀀ects how ecosystems respond to natural and anthropogenic crises, and whether species or the ecological functions that they represent are able to persist. Here we use fossil data from museum collections, literature, and the Paleobiology Database to reconstruct trophic networks of Tethyan paleocommunities fromthe Anisian and Carnian (Triassic), Bathonian (Jurassic), and Aptian (Cretaceous) stages, and compare these to a previously reconstructed trophic network from a modern Jamaican reef community. We generated model food webs consistent with …

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Acreage Of Foreign Owned Farmland In The Mountain West, 2020, Geneva Martin, Saha Salahi, Zachary Billot, Caitlin J. Saladino, William E. Brown Jr. Aug 2022

Acreage Of Foreign Owned Farmland In The Mountain West, 2020, Geneva Martin, Saha Salahi, Zachary Billot, Caitlin J. Saladino, William E. Brown Jr.

Housing & Real Estate

This fact sheet examines foreign-owned farmland in the Mountain West states of Arizona, Colorado, Nevada, New Mexico, and Utah, as originally reported by the United States Department of Agriculture’s (USDA) Farm Service Agency.

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Renewable Energy Legislation In Nevada: 2017 - 2021, Peter Grema, Zachary Walusek, Caitlin J. Saladino, William E. Brown Jr. Aug 2022

Renewable Energy Legislation In Nevada: 2017 - 2021, Peter Grema, Zachary Walusek, Caitlin J. Saladino, William E. Brown Jr.

Environment

The purpose of this fact sheet is to summarize legislative actions from the biennial 79th, 80th, and 81st Nevada Legislative Sessions (2017, 2019, and 2021) regarding solar energy production and state efforts to reach 50 percent energy production from renewable sources by 2030. By 2050, Nevada has a statutorily mandated obligation to be a net-zero carbon producer in fulfilling energy production needs from large scale utility services.

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Artificial Intelligence In The Radiomic Analysis Of Glioblastomas: A Review, Taxonomy, And Perspective, Ming Zhu, Sijia Li, Yu Kuang, Virginia B. Hill, Amy B. Heimberger, Lijie Zhai, Shenjie Zhai Aug 2022

Artificial Intelligence In The Radiomic Analysis Of Glioblastomas: A Review, Taxonomy, And Perspective, Ming Zhu, Sijia Li, Yu Kuang, Virginia B. Hill, Amy B. Heimberger, Lijie Zhai, Shenjie Zhai

Electrical & Computer Engineering Faculty Research

Radiological imaging techniques, including magnetic resonance imaging (MRI) and positron emission tomography (PET), are the standard-of-care non-invasive diagnostic approaches widely applied in neuro-oncology. Unfortunately, accurate interpretation of radiological imaging data is constantly challenged by the indistinguishable radiological image features shared by different pathological changes associated with tumor progression and/or various therapeutic interventions. In recent years, machine learning (ML)-based artificial intelligence (AI) technology has been widely applied in medical image processing and bioinformatics due to its advantages in implicit image feature extraction and integrative data analysis. Despite its recent rapid development, ML technology still faces many hurdles for its broader applications …

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Wildfire Risk In Mountain West States, 2017-2021, Olivia K. Cheche, Corryn Richardson, Zachary Billot, Miguel Soriano Ralston, Vanessa Booth, Caitlin J. Saladino, William E. Brown Jr. Jul 2022

Wildfire Risk In Mountain West States, 2017-2021, Olivia K. Cheche, Corryn Richardson, Zachary Billot, Miguel Soriano Ralston, Vanessa Booth, Caitlin J. Saladino, William E. Brown Jr.

Environment

This fact sheet examines data on wildfire destruction in the Mountain West states of Arizona, Colorado, Nevada, New Mexico, and Utah. The original report from the Insurance Information Institute presents findings on percent of properties at risk of wildfire destruction, the number of wildfires by state, and numbers of acres burned per state.

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Steel Module-To-Concrete Core Connection Methods In High Rise Modular Buildings: A Critical Review, Bishal Poudel, Seungtaek Lee, Jin Ouk Choi Jun 2022

Steel Module-To-Concrete Core Connection Methods In High Rise Modular Buildings: A Critical Review, Bishal Poudel, Seungtaek Lee, Jin Ouk Choi

Civil and Environmental Engineering and Construction Faculty Research

Modularization in a high-rise building is different from a small building, as it is exposed to more lateral forces like wind and earthquakes. The integrity, robustness, and overall stability of the modules and their performance is based on the joining techniques and strong structural systems. High lateral stiff construction structures like concrete shear walls and frames, braced steel frames, and steel moment frames are used for the stability of high-rise modular buildings. Similarly, high-rise stick-built buildings have concrete cores and perimeter frames for lateral load strength and stiffness. Methods for general steel-concrete connections are available in many works of literature. …

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A Generalized Family Of Exponentiated Composite Distributions, Bowen Liu, Malwane Ananda Jun 2022

A Generalized Family Of Exponentiated Composite Distributions, Bowen Liu, Malwane Ananda

Mathematical Sciences Faculty Research

In this paper, we propose a new family of distributions, by exponentiating the random variables associated with the probability density functions of composite distributions. We also derive some mathematical properties of this new family of distributions, including the moments and the limited moments. Specifically, two special models in this family are discussed. Three real datasets were chosen, to assess the performance of these two special exponentiated-composite models. When fitting to these three datasets, these three special exponentiated-composite distributions demonstrate significantly better performance, compared to the original composite distributions.

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Evaluating The Behaviour Of Centrally Perforated Unreinforced Masonry Walls: Applications Of Numerical Analysis, Machine Learning, And Stochastic Methods, Mohsen Khaleghi, Javid Salimi, Visar Farhangi, Mohammad Javad Moradi, Moses Karakouzian May 2022

Evaluating The Behaviour Of Centrally Perforated Unreinforced Masonry Walls: Applications Of Numerical Analysis, Machine Learning, And Stochastic Methods, Mohsen Khaleghi, Javid Salimi, Visar Farhangi, Mohammad Javad Moradi, Moses Karakouzian

Civil and Environmental Engineering and Construction Faculty Research

The presence of openings greatly affects the response of unreinforced masonry (URM) walls. This topic greatly attracts the attention of many researchers. Perforated unreinforced masonry (PURM) walls under in-plane loads through the truss discretization method (TDM) along with several machine learning approaches such as Multilayer perceptron (MLP), Group of Method Data Handling (GMDH), and Radial basis function (RBF) are described in this paper. A new method named Multi-pier (MP) that is fast and accurate, is used to determine the behavior of PURM walls. The results of the MP method are expressed as a ratio of lateral load-bearing capacity and initial …

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Quantification Of Organic Carbon Sequestered By Biogenic Iron Sulfide Minerals In Long-Term Anoxic Laboratory Incubations, Nader Nabeh, Cheyenne Brokaw, Aude Picard Apr 2022

Quantification Of Organic Carbon Sequestered By Biogenic Iron Sulfide Minerals In Long-Term Anoxic Laboratory Incubations, Nader Nabeh, Cheyenne Brokaw, Aude Picard

Life Sciences Faculty Research

Organic carbon sequestration in sedimentary environments controls oxygen and carbon dioxide concentrations in the atmosphere. While minerals play an important role in the preservation of organic carbon, there is a lack of understanding about the formation and stability of organo-mineral interactions in anoxic environments, especially those involving authigenic iron sulfide minerals. In this study, we quantified organic carbon and nitrogen sequestered in biogenic iron sulfide minerals co-precipitated with sulfate-reducing bacteria (SRB) in freshwater and marine conditions in long-term laboratory experiments. The amounts of C and N associated with biogenic iron sulfide minerals increased with increasing cell biomass concentrations available in …

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Artificial Intelligence Framework Identifies Candidate Targets For Drug Repurposing In Alzheimer’S Disease, Jiansong Fang, Pengyue Zhang, Quan Wang, Chien Wei Chiang, Yadi Zhou, Yuan Hou, Jielin Xu, Rui Chen, Bin Zhang, Stephen J. Lewis, James B. Leverenz, Andrew A. Pieper, Bingshan Li, Lang Li, Jeffrey Cummings, Feixiong Cheng Jan 2022

Artificial Intelligence Framework Identifies Candidate Targets For Drug Repurposing In Alzheimer’S Disease, Jiansong Fang, Pengyue Zhang, Quan Wang, Chien Wei Chiang, Yadi Zhou, Yuan Hou, Jielin Xu, Rui Chen, Bin Zhang, Stephen J. Lewis, James B. Leverenz, Andrew A. Pieper, Bingshan Li, Lang Li, Jeffrey Cummings, Feixiong Cheng

Brain Health Faculty Publications

Background: Genome-wide association studies (GWAS) have identified numerous susceptibility loci for Alzheimer’s disease (AD). However, utilizing GWAS and multi-omics data to identify high-confidence AD risk genes (ARGs) and druggable targets that can guide development of new therapeutics for patients suffering from AD has heretofore not been successful. Methods: To address this critical problem in the field, we have developed a network-based artificial intelligence framework that is capable of integrating multi-omics data along with human protein–protein interactome networks to accurately infer accurate drug targets impacted by GWAS-identified variants to identify new therapeutics. When applied to AD, this approach integrates GWAS findings, …

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Novel Architecture Of Onem2m-Based Convergence Platform For Mixed Reality And Iot, Seungwoon Lee, Woogeun Kil, Byeong Hee Roh, Si-Jung Kim, Jin Suk Kang Jan 2022

Novel Architecture Of Onem2m-Based Convergence Platform For Mixed Reality And Iot, Seungwoon Lee, Woogeun Kil, Byeong Hee Roh, Si-Jung Kim, Jin Suk Kang

College of Engineering Faculty Research

There have been numerous works proposed to merge augmented reality/mixed reality (AR/MR) and Internet of Things (IoT) in various ways. However, they have focused on their specific target applications and have limitations on interoperability or reusability when utilizing them to different domains or adding other devices to the system. This paper proposes a novel architecture of a convergence platform for AR/MR and IoT systems and services. The proposed architecture adopts the oneM2M IoT standard as the basic framework that converges AR/MR and IoT systems and enables the development of application services used in general-purpose environments without being subordinate to specific …

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An Approach For Material Model Identification Of A Composite Coating Using Micro-Indentation And Multi-Scale Simulations, Pouya Shojaei, Riccardo Scazzosi, Mohamed Trabia, Brendan O’Toole, Marco Giglio, Xing Zhang, Yiliang Liao, Andrea Manes Jan 2022

An Approach For Material Model Identification Of A Composite Coating Using Micro-Indentation And Multi-Scale Simulations, Pouya Shojaei, Riccardo Scazzosi, Mohamed Trabia, Brendan O’Toole, Marco Giglio, Xing Zhang, Yiliang Liao, Andrea Manes

Mechanical Engineering Faculty Research

While deposited thin film coatings can help enhance surface characteristics such as hardness and friction, their effective incorporation in product design is restricted by the limited understand-ing of their mechanical behavior. To address this, an approach combining micro-indentation and meso/micro-scale simulations was proposed. In this approach, micro-indentation testing was conducted on both the coating and the substrate. A meso-scale uniaxial compression finite element model was developed to obtain a material model of the coating. This material model was incorporated within an axisymmetric micro-scale model of the coating to simulate the indentation. The proposed approach was applied to a Ti/SiC metal …

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Evaluation Of Continuous Power-Down Schemes, James Andro-Vasko, Wolfgang Bein Jan 2022

Evaluation Of Continuous Power-Down Schemes, James Andro-Vasko, Wolfgang Bein

Computer Science Faculty Research

We consider a power-down system with two states—“on” and “off”—and a continuous set of power states. The system has to respond to requests for service in the “on” state and, after service, the system can power off or switch to any of the intermediate power-saving states. The choice of states determines the cost to power on for subsequent requests. The protocol for requests is “online”, which means that the decision as to which intermediate state (or the off-state) the system will switch has to be made without knowledge of future requests. We model a linear and a non-linear system, and …

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Stability And Mechanical Properties Of W1-X Mox B4.2 (X=0.0-1.0) From First Principles, Weiguang Gong, Rui Xu, Xuecheng Shao, Quan Li, Changfeng Chen Dec 2021

Stability And Mechanical Properties Of W1-X Mox B4.2 (X=0.0-1.0) From First Principles, Weiguang Gong, Rui Xu, Xuecheng Shao, Quan Li, Changfeng Chen

Physics & Astronomy Faculty Research

Heavy transition-metal tetraborides (e.g., tungsten tetraboride, molybdenum tetraboride, and molybdenum-doped tungsten tetraboride) exhibit superior mechanical properties, but solving their complex crystal structures has been a long-standing challenge. Recent experimental x-ray and neutron diffraction measurements combined with first-principles structural searches have identified a complex structure model for tungsten tetraboride that contains a boron trimer as an unusual structural unit with a stoichiometry of 1:4.2. In this paper, we expand the study to binary MoB4.2 and ternary W1-xMoxB4.2 (x=0.0-1.0) compounds to assess their thermodynamic stability and mechanical properties using a tailor-designed crystal structure search method in conjunction with first-principles energetic calculations. Our …

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Numerical Modeling Of Mineralizing Processes During The Formation Of The Yangzhuang Kiruna-Type Iron Deposit, Middle And Lower Yangtze River Metallogenic Belt, China: Implications For The Genesis And Longevity Of Kiruna-Type Iron Oxide-Apatite Systems, Xunyu Hu, Simon Jowitt, Feng Yuan, Guangxian Liu, Jinhui Luo, Yuhua Chen, Hui Yang, Keyue Ren, Yongguo Yang Dec 2021

Numerical Modeling Of Mineralizing Processes During The Formation Of The Yangzhuang Kiruna-Type Iron Deposit, Middle And Lower Yangtze River Metallogenic Belt, China: Implications For The Genesis And Longevity Of Kiruna-Type Iron Oxide-Apatite Systems, Xunyu Hu, Simon Jowitt, Feng Yuan, Guangxian Liu, Jinhui Luo, Yuhua Chen, Hui Yang, Keyue Ren, Yongguo Yang

Geoscience Faculty Publications

The Yangzhuang iron deposit is a Kiruna-type iron oxide-apatite (IOA) deposit within the Ningwu mining district of the Middle and Lower Yangtze River Metallogenic Belt (MLYRMB), China. This study applies a numerical modeling approach to identify the key processes associated with the formation of the deposit that cannot be easily identified using traditional analytical approaches, including the duration of the mineralizing process and the genesis of iron orebodies within intrusions associated with the deposit. This approach highlights the practical value of numerical modeling in quantitatively analyzing mineralizing processes during the formation of mineral deposits and assesses how these methods can …

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Eccentric Neutron Star Disk Driven Type Ii Outburst Pairs In Be/X-Ray Binaries, Alessia Franchini, Rebecca G. Martin Dec 2021

Eccentric Neutron Star Disk Driven Type Ii Outburst Pairs In Be/X-Ray Binaries, Alessia Franchini, Rebecca G. Martin

Physics & Astronomy Faculty Research

Be star X-ray binaries are transient systems that show two different types of outbursts. Type I outbursts occur each orbital period while type II outbursts have a period and duration that are not related to any periodicity of the binary system. Type II outbursts may be caused by mass transfer to the neutron star from a highly eccentric Be star disk. A sufficiently misaligned Be star decretion disk undergoes secular Von Zeipel-Lidov-Kozai (ZLK) oscillations of eccentricity and inclination. Observations show that in some systems the type II outbursts come in pairs with the second being of lower luminosity. We use …

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Machine Learning And Radiomic Features To Predict Overall Survival Time For Glioblastoma Patients, Lina Chato, Shahram Latifi Dec 2021

Machine Learning And Radiomic Features To Predict Overall Survival Time For Glioblastoma Patients, Lina Chato, Shahram Latifi

Electrical & Computer Engineering Faculty Research

Glioblastoma is an aggressive brain tumor with a low survival rate. Understanding tumor behavior by predicting prognosis outcomes is a crucial factor in deciding a proper treatment plan. In this paper, an automatic overall survival time prediction system (OST) for glioblastoma patients is developed on the basis of radiomic features and machine learning (ML). This system is designed to predict prognosis outcomes by classifying a glioblastoma patient into one of three survival groups: short-term, mid-term, and long-term. To develop the prediction system, a medical dataset based on imaging information from magnetic resonance imaging (MRI) and non-imaging information is used. A …

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Data Of The Constructivist Practices In The Learning Environment Survey From Engineering Undergraduates: An Exploratory Factor Analysis, Chengcheng Li, Shaoan Zhang, Tiberio Garza, Yingtao Jiang Dec 2021

Data Of The Constructivist Practices In The Learning Environment Survey From Engineering Undergraduates: An Exploratory Factor Analysis, Chengcheng Li, Shaoan Zhang, Tiberio Garza, Yingtao Jiang

Teaching and Learning Faculty Research

This paper presents the dataset of a questionnaire on first-year engineering undergraduates’ perceptions of constructivist practices in the learning environment. The questionnaire with a 5-Likert scale was adapted from previous research. The sample consisted of 293 first-year engineering undergraduates in the southwest region of the United States. The online questionnaire was sent to participants who completed it voluntarily at the end of Fall 2019. A total of 274 of 293 participants completed the questionnaire with a response rate of 93.515%. Exploratory factor analysis was conducted to test the underlying factor structure of the questionnaire, which serves as a good reference …

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Nonperiodic Type I Be/X-Ray Binary Outbursts, Rebecca G. Martin, Alessia Franchini Dec 2021

Nonperiodic Type I Be/X-Ray Binary Outbursts, Rebecca G. Martin, Alessia Franchini

Physics & Astronomy Faculty Research

Type I Be/X-ray binary outbursts are driven by mass transfer from a Be star decretion disk to a neutron star companion during each orbital period. Treiber et al. recently observed nonperiodic type I outbursts in RX J0529.8-6556 that has unknown binary orbital properties. We show that nonperiodic type I outbursts may be temporarily driven in a low eccentricity binary with a disk that is inclined sufficiently to be mildly unstable to Kozai-Lidov oscillations. The inclined disk becomes eccentric and material is transferred to the neutron star at up to three locations in each orbit: when the neutron star passes the …

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Characteristics Of Flow Over Rectangular Labyrinth Weirs With Round Corners, Omed S.Q. Yousif, Kawa Z. Abdulrahman, Wazira Qadir, Ahang S. Ali, Moses Karakouzian Dec 2021

Characteristics Of Flow Over Rectangular Labyrinth Weirs With Round Corners, Omed S.Q. Yousif, Kawa Z. Abdulrahman, Wazira Qadir, Ahang S. Ali, Moses Karakouzian

Civil and Environmental Engineering and Construction Faculty Research

The hydraulic performance of round-cornered rectangular labyrinth weirs with varying weir heights and effective lengths has not been explored in the existing literature to the authors’ knowledge. The purpose of this experimental study was to see how the height and effective length of round-cornered rectangular labyrinth weirs affect their discharge efficiency. Nine flat-crested rectangular labyrinth weirs made of high-density polyethylene (HDPE) were tested in a rectangular flume under various discharges to fulfill the goals of this study. The discharge coefficients for the weirs were then calculated. The hydraulic efficiency of weirs with round corners increases as the weir height (P) …

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