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Full-Text Articles in Physical Sciences and Mathematics

Gravitational-Wave Science With The Laser Interferometer Gravitational-Wave Observatory, Madeline Wade May 2017

Gravitational-Wave Science With The Laser Interferometer Gravitational-Wave Observatory, Madeline Wade

Madeline Wade

Gravitational-waves, as predicted by Einstein’s theory of general relativity, are oscillations of spacetime caused by the motion of masses. Although not yet directly detected, there is strong evidence for the existence of gravitational-waves. Detectable gravitational waves will come from dramatic astrophysical events, such as supernova explosions and collisions of black holes. The Laser Interferometer Gravitational-wave Observatory (LIGO) is a network of detectors designed to make the first direct detection of gravitational waves. The upgraded version of LIGO, Advanced LIGO (aLIGO), will offer a dramatic improvement in sensitivity that will virtually guarantee detections. Gravitational-wave detections will not only illuminate mysterious astrophysical …


Gravitational Waves From Rotating Neutron Stars And Compact Binary Systems, Leslie Wade May 2017

Gravitational Waves From Rotating Neutron Stars And Compact Binary Systems, Leslie Wade

Leslie Wade

It is widely anticipated that the first direct detections of gravitational waves will be made by advanced gravitational-wave detectors, such as the two Laser Interferometer Gravitational-wave Observatories (LIGO) and the Virgo interferometer. In preparation for the advanced detector era, I have worked on both detection and post-detection efforts involving two gravitational wave sources: isolated rotating neutron stars (NSs) and compact binary coalescences (CBCs). My dissertation includes three main research projects: 1) a population synthesis study assessing the detectability of isolated NSs, 2) a CBC search for intermediate-mass black-hole binaries (IMBHBs), and 3) new methods for directly measuring the neutron-star (NS) …


Vector Acoustic Intensity Around A Tuning Fork, Daniel A. Russell, Justin Junell, Daniel O. Ludwigsen May 2017

Vector Acoustic Intensity Around A Tuning Fork, Daniel A. Russell, Justin Junell, Daniel O. Ludwigsen

Daniel Ludwigsen

The acoustic intensity vector field around a tuning fork is investigated. Theory for a longitudinal quadrupole source predicts a well-defined transition between near-field and far-field, with significant circulation of sound energy in the near-field. Vector components of the time-averaged intensity were measured using a two-microphone intensity probe and found to agree well with predictions from theory. The vector intensity map is interpreted, and shown to provide useful information about the near-field of an acoustic source.


A Simple Electric Field Probe In A Gauss's Law Laboratory, Daniel O. Ludwigsen, Gregory N. Hassold May 2017

A Simple Electric Field Probe In A Gauss's Law Laboratory, Daniel O. Ludwigsen, Gregory N. Hassold

Daniel Ludwigsen

Early in our calculus-based introductory course, students are introduced to electric fields and sometimes struggle with the abstraction of a vector field. They have less familiarity with the phenomena associated with electric fields, and the connection between phenomena and mathematical formalism is weaker. Our very next topic is Gauss's law.


Better Understanding Of Resonance Through Modeling And Visualization, Daniel O. Ludwigsen, Cayla Jewett, Matthew Jusczcyk May 2017

Better Understanding Of Resonance Through Modeling And Visualization, Daniel O. Ludwigsen, Cayla Jewett, Matthew Jusczcyk

Daniel Ludwigsen

Students encounter cavity resonance and waveguide phenomena in acoustics courses and texts, where the study is usually limited to cases with simple geometries: parallelepipeds, cylinders, and spheres. Long-wavelength approximations help with situations of more complexity, as in the classic Helmholtz resonator. At Kettering University, we are beginning to employ finite element modeling in our acoustics classes to help undergraduates better understand the acoustic modes of actual structures. This approach to the time-independent wave equation (the Helmholtz equation) was first used in a research and measurements class to investigate two classic resonance problems. The first problem was a study of resonance …


Choose Wisely: Static Or Kinetic Friction—The Power Of Dimensionless Plots, Daniel O. Ludwigsen, Kathryn A. Svinarich May 2017

Choose Wisely: Static Or Kinetic Friction—The Power Of Dimensionless Plots, Daniel O. Ludwigsen, Kathryn A. Svinarich

Daniel Ludwigsen

Consider a problem of sliding blocks, one stacked atop the other, resting on a friction-less table. If the bottom block is pulled horizontally, nature makes a choice: if the applied force is small, static friction between the blocks accelerates the blocks together, but with a large force the blocks slide apart. In that case, kinetic friction still forces the upper block forward but with less acceleration than the lower block. The choice, then, lies in the relative terms—what is meant by small and large? After a confusing experience during a recent exam, we’ve found a demonstration and graphical presentation that …


Acoustic Testing And Modeling: An Advanced Undergraduate Laboratory, Daniel A. Russell, Daniel O. Ludwigsen May 2017

Acoustic Testing And Modeling: An Advanced Undergraduate Laboratory, Daniel A. Russell, Daniel O. Ludwigsen

Daniel Ludwigsen

This paper describes an advanced laboratory course in acoustics, specifically targeted for students with an interest in engineering applications at a school with a strongly integrated industrial co-op program. The laboratory course is developed around a three-pronged approach to problem solving that combines and integrates theoretical models, computational models, and experimental data. The course is structured around modules that begin with fundamental concepts and build laboratory skills and expand the knowledge base toward a final project. Students keep a detailed laboratory notebook, write research papers in teams, and must pass laboratory certification exams. This paper describes the course layout and …


Vitamin D Status And Demographic And Lifestyle Determinants Among Adults In The United States (Nhanes 2001-2006), Yan Cao, Katie L. Callahan, Sreenivas P. Veeranki, Yang Chen, Ying Liu, Shimin Zheng May 2017

Vitamin D Status And Demographic And Lifestyle Determinants Among Adults In The United States (Nhanes 2001-2006), Yan Cao, Katie L. Callahan, Sreenivas P. Veeranki, Yang Chen, Ying Liu, Shimin Zheng

Shimin Zheng

This study looked at risk factors associated with vitamin D levels in the body among a representative sample of adults in the U.S., NHANES III (2001-2006) data were used to assess the relationship between several demographic and health risk factors and vitamin D levels in the body. The Baseline-Category Logit Model was used to test the association between vitamin D level and the potential risk factors age, education, ethnicity, poverty status, physical activity, smoking, alcohol, obesity, diabetes and total cholesterol with both genders. Vitamin D insufficiency and deficiency were significantly associated with age, race, education, physical activity, obesity, diabetes and …


Random Regression Models Based On The Elliptically Contoured Distribution Assumptions With Applications To Longitudinal Data, Alfred A. Bartolucci, Shimin Zheng, Sejong Bae, Karan P. Singh May 2017

Random Regression Models Based On The Elliptically Contoured Distribution Assumptions With Applications To Longitudinal Data, Alfred A. Bartolucci, Shimin Zheng, Sejong Bae, Karan P. Singh

Shimin Zheng

We generalize Lyles et al.’s (2000) random regression models for longitudinal data, accounting for both undetectable values and informative drop-outs in the distribution assumptions. Our models are constructed on the generalized multivariate theory which is based on the Elliptically Contoured Distribution (ECD). The estimation of the fixed parameters in the random regression models are invariant under the normal or the ECD assumptions. For the Human Immunodeficiency Virus Epidemiology Research Study data, ECD models fit the data better than classical normal models according to the Akaike (1974) Information Criterion. We also note that both univariate distributions of the random intercept and …


The Use Of Vital Statistics Data For Research Of Consequence: Birth Outcomes And Population Health In A Rural Region, Claudia Kozinetz, Shimin Zheng, Eunice Mogusu May 2017

The Use Of Vital Statistics Data For Research Of Consequence: Birth Outcomes And Population Health In A Rural Region, Claudia Kozinetz, Shimin Zheng, Eunice Mogusu

Shimin Zheng

Objective: The Affordable Care Act (ACA) has influenced increasing interests in population health and population health outcomes. The purpose of this study was to exemplify the importance of using existing vital statistics data for understanding and monitoring health outcomes and consequentially health disparities at the population level. Data from birth records for two geographic regions from 2009-2014 were compared; low birth weight (LBW) and preterm delivery (PD) were used as surrogates for population health outcomes. Methods: A population-based, multi-year, cross-sectional study design using a pooled dataset of birth records from Tennessee (TN) was the framework for the analyses. A sub-population …


Trends And Determinants Of Up-To-Date Status With Colorectal Cancer Screening In Tennessee, 2002-2008, Sreenivas P. Veeranki, Shimin Zheng May 2017

Trends And Determinants Of Up-To-Date Status With Colorectal Cancer Screening In Tennessee, 2002-2008, Sreenivas P. Veeranki, Shimin Zheng

Shimin Zheng

BACKGROUND: Screening rates for colorectal cancer (CRC) are increasing nationwide including Tennessee (TN); however, their up-to-date status is unknown. The objective of this study is to determine the trends and characteristics of TN adults who are up-to-date status with CRC screening during 2002-2008. METHODS: We examined data from the TN Behavioral Risk Factor Surveillance System for 2002, 2004, 2006 and 2008 to estimate the proportion of respondents aged 50 years and above who were up-to-date status with CRC screening, defined as an annual home fecal occult blood test and/or sigmoidoscopy or colonoscopy in the past 5 years. We identified trends …


The Association Of Calcium Intake And Other Risk Factors With Cardiovascular Disease Among Obese Adults In Usa, Yang Chen, Sheryl Strasser, Katie Callahan, David Blackley, Yan Cao, Liang Wang, Shimin Zheng May 2017

The Association Of Calcium Intake And Other Risk Factors With Cardiovascular Disease Among Obese Adults In Usa, Yang Chen, Sheryl Strasser, Katie Callahan, David Blackley, Yan Cao, Liang Wang, Shimin Zheng

Shimin Zheng

In this study, we used a cross-sectional study design to examine the relationship between the calcium intake and risk factors for CVD among obese adults by using continuous waves of National Health and Nutrition Examination Survey (NHANES) data 1999-2010. The association between calcium intake and risk factors of CVD (hypertension, total cholesterol, HDL, glycohemoglobin), CRP, albuminuria) is assessed among obese adults in USA. The incidence of Cardiovascular Disease (CVD) is high among obese people. The potential effects of inadequate calcium intake on CVD are receiving increased epidemiologic attention. Understanding the association between risk factors for CVD and calcium intake among …


Screening For Elder Mistreatment Among Older Adults Seeking Legal Assistance Services, Sheryl M. Strasser, Megan Smith, Scott Weaver, Shimin Zheng, Yan Cao May 2017

Screening For Elder Mistreatment Among Older Adults Seeking Legal Assistance Services, Sheryl M. Strasser, Megan Smith, Scott Weaver, Shimin Zheng, Yan Cao

Shimin Zheng

Introduction: The aging population is a rapidly growing demographic in the United States. Isolation, limited autonomy, and declining physical and mental health render many older adults vulnerable to elder mistreatment (EM). The purpose of this study was to assess the prevalence and correlates of EM among a sample of older adults using legal assistance services in Atlanta, Georgia. Methods: Researchers administered surveys to consenting older adults (aged 60þ) in 5 metro Atlanta community centers that hosted legal assistance information sessions as part of the Elderly Legal Assistance Program. The surveys screened for risk factors and prevalence of EM risk using …


Stochastic Representations Of The Matrix Variate Skew Elliptically Contoured Distributions, Shimin Zheng, Chunming Zhang, Jeff Knisley May 2017

Stochastic Representations Of The Matrix Variate Skew Elliptically Contoured Distributions, Shimin Zheng, Chunming Zhang, Jeff Knisley

Shimin Zheng

Matrix variate skew elliptically contoured distributions generalize several classes of important distributions. This paper defines and explores matrix variate skew elliptically contoured distributions. In particular, we discuss two stochastic representations of the matrix variate skew elliptically contoured distributions.


Predictors Of Neonatal Abstinence Syndrome In Buprenorphine Exposed Newborn: Can Cord Blood Buprenorphine Metabolite Levels Help?, Darshan Shah, Stacy Brown, Nick Hagemeier, Shimin Zheng, Amy Kyle, Jason Pryor, Nilesh Dankhara, Piyuesh Singh May 2017

Predictors Of Neonatal Abstinence Syndrome In Buprenorphine Exposed Newborn: Can Cord Blood Buprenorphine Metabolite Levels Help?, Darshan Shah, Stacy Brown, Nick Hagemeier, Shimin Zheng, Amy Kyle, Jason Pryor, Nilesh Dankhara, Piyuesh Singh

Shimin Zheng

Background

Buprenorphine is a semi-synthetic opioid used for the treatment of opioid dependence. Opioid use, including buprenorphine, has been increasing in recent years, in the general population and in pregnant women. Consequently, there has been a rise in frequency of neonatal abstinence syndrome (NAS), associated with buprenorphine use during pregnancy. The purpose of this study was to investigate correlations between buprenorphine and buprenorphine-metabolite concentrations in cord blood and onset of NAS in buprenorphine exposed newborns.

Methods

Nineteen (19) newborns who met inclusion criteria were followed after birth until discharge in a double-blind non-intervention study, after maternal consent. Cord blood and …


Prevalence Of And Risk Factors For Adolescent Obesity In Tennessee Using The 2010 Youth Risk Behavior Survey (Yrbs) Data: An Analysis Using Weighted Hierarchical Logistic Regression, Shimin Zheng, Nicole Holt, Jodi L. Southerland, Yan Cao, Trevor Taylor, Deborah L. Slawson, Mark Bloodworth May 2017

Prevalence Of And Risk Factors For Adolescent Obesity In Tennessee Using The 2010 Youth Risk Behavior Survey (Yrbs) Data: An Analysis Using Weighted Hierarchical Logistic Regression, Shimin Zheng, Nicole Holt, Jodi L. Southerland, Yan Cao, Trevor Taylor, Deborah L. Slawson, Mark Bloodworth

Shimin Zheng

Background: The rate of adolescent overweight and obesity has more than quadrupled over the past few decades, and has become a major public health problem [1]. In 2011, 55% of 12-19 year olds in the United States (U.S.) were overweight or obese [2]. Adolescence is a pivotal time in which many health risk behaviors such as tobacco, alcohol, and drug use are initiated. Such health risk behaviors have been significantly associated with overweight and obesity among adolescents. Objective: The purpose of this study is to evaluate the relationship between obesity and the health risk behaviors most commonly associated with premature …


Predictors Of Treatments Acceptable To Patients For Late-Life Depression, Gerald J. Jogerst, Shimin Zheng, Erik Vanderlip May 2017

Predictors Of Treatments Acceptable To Patients For Late-Life Depression, Gerald J. Jogerst, Shimin Zheng, Erik Vanderlip

Shimin Zheng

Objectives. Describe older patients’ perceptions about depression and characteristics associated with acceptance of treatments. Design. Cross-sectional study. Setting. Three primary care clinics in Iowa. Participants. Consecutive sample of 529 primary care patients. Measurements. Depression screening tool (a 9-item patient health questionnaire [PHQ-9]) and questionnaire including sociodemographic data, patient attitudes about depression, and acceptability of different treatments. Results. Mean age was 71.9 years (range 60–93 years), 314 (59%) female. Among the 529 participants, 93 (17.5%) had history of depression and 60 (11.3%) had PHQ-9 scores of 10 or greater. Participants believed depression is a disease for which they would use medication …


Moments Of Matrix Variate Skew Elliptically Contoured Distributions, Shimin Zheng, Jeff Knisley, Chunming Zhang May 2017

Moments Of Matrix Variate Skew Elliptically Contoured Distributions, Shimin Zheng, Jeff Knisley, Chunming Zhang

Shimin Zheng

Matrix variate skew elliptically contoured distributions generalize several classes of important distributions. This paper defines and explores matrix variate skew elliptically contoured distributions. In particular, we discuss the first two moments of the matrix variate skew elliptically contoured distributions.


Associations Of Smoking Status And Serious Psychological Distress With Chronic Obstructive Pulmonary Disease, Ke-Sheng Wang, Liang Wang, Shimin Zheng, Long-Yang Wu May 2017

Associations Of Smoking Status And Serious Psychological Distress With Chronic Obstructive Pulmonary Disease, Ke-Sheng Wang, Liang Wang, Shimin Zheng, Long-Yang Wu

Shimin Zheng

Background: Chronic obstructive pulmonary disease (COPD) has been a major public health problem due to its high prevalence, morbidity, and mortality. Smoking is a major risk factor for COPD, while serious psychological distress (SPD) is prevalent among COPD patients. However, no study focusing on the effect of SPD on COPD has been so far conducted, while few studies have focused on the associations of SPD and behavioral factors with COPD by smoking status. Objectives: This study aimed to examine the associations of SPD and behavioral factors (such as smoking and physical activity) with COPD. Materials and Methods: Weighted logistic regression …


Beyond 3 Au From The Sun: The Hypervolatiles Ch4, C2h6, And Co In The Distant Comet C/2006 W3 (Christensen), Boncho P. Bonev, Geronimo L. Villanueva, Michael A. Disanti, Hermann Boehnhardt, Manuela Lippi, Erika L. Gibb, Lucas Paganini, Michael J. Mumma May 2017

Beyond 3 Au From The Sun: The Hypervolatiles Ch4, C2h6, And Co In The Distant Comet C/2006 W3 (Christensen), Boncho P. Bonev, Geronimo L. Villanueva, Michael A. Disanti, Hermann Boehnhardt, Manuela Lippi, Erika L. Gibb, Lucas Paganini, Michael J. Mumma

Erika Gibb

Comet C/2006 W3 (Christensen) remained outside a heliocentric distance (R h) of 3.1 au throughout its apparition, but it presented an exceptional opportunity to directly sense a suite of molecules released from its nucleus. The Cryogenic Infrared Echelle Spectrograph at ESO-VLT detected infrared emissions from the three "hypervolatiles" (CO, CH4, and C2H6) that have the lowest sublimation temperatures among species that are commonly studied in comets by remote sensing. Even at R h = 3.25 au, the production rate of each molecule exceeded those measured for the same species in a number of other comets, although these comets were observed …


Osspal: Finding And Evaluating Open Source Software, Anthony Wasserman Apr 2017

Osspal: Finding And Evaluating Open Source Software, Anthony Wasserman

Tony Wasserman

This paper describes the OSSpal project, which is aimed at helping companies, government agencies, and other organizations find high quality free and open source software (FOSS) that meets their needs. OSSpal is a successor to the Business Readiness Rating (BRR), combining quantitative and qualitative evaluation measures for software in various categories. Instead of a purely numeric calculated score OSSpal adds curation of high-quality FOSS projects and individual user reviews of these criteria. Unlike the BRR project, for which there was no automated support, OSSpal has an operational, publicly available website where users may search by project name or category, and …


Decision-Making With Cross-Entropy For Self-Adaptation, Gabriel A. Moreno, Ofer Strichman, Sagar Chaki, Radislav Vaisman Apr 2017

Decision-Making With Cross-Entropy For Self-Adaptation, Gabriel A. Moreno, Ofer Strichman, Sagar Chaki, Radislav Vaisman

Gabriel A. Moreno

Approaches to decision-making in self-adaptive systems are increasingly becoming more effective at managing the target system by taking into account more elements of the decision problem that were previously ignored. These approaches have to solve complex optimization problems at run time, and even though they have been shown to be suitable for different kinds of systems, their time complexity can make them excessively slow for systems that have a large adaptation-relevant state space, or that require a tight control loop driven by fast decisions. In this paper we present an approach to speed up complex proactive latency-aware self-adaptation decisions, using …


Comparing Model-Based Predictive Approaches To Self-Adaptation: Cobra And Pla, Gabriel A. Moreno, Alessandro V. Papadopoulos, Konstantinos Angelopoulos, Javier Camara, Bradley Schmerl Apr 2017

Comparing Model-Based Predictive Approaches To Self-Adaptation: Cobra And Pla, Gabriel A. Moreno, Alessandro V. Papadopoulos, Konstantinos Angelopoulos, Javier Camara, Bradley Schmerl

Gabriel A. Moreno

Modern software-intensive systems must often guarantee certain quality requirements under changing run-time conditions and high levels of uncertainty. Self-adaptation has proven to be an effective way to engineer systems that can address such challenges, but many of these approaches are purely reactive and adapt only after a failure has taken place. To overcome some of the limitations of reactive approaches (e.g., lagging behind environment changes and favoring short-term improvements), recent proactive self-adaptation mechanisms apply ideas from control theory, such as model predictive control (MPC), to improve adaptation. When selecting which MPC approach to apply, the improvement that can be obtained …


Sustainability And Global Environmental Constitutionalism, James R. May Apr 2017

Sustainability And Global Environmental Constitutionalism, James R. May

James R. May

No abstract provided.


Ispy: Threats To Individual And Institutional Privacy In The Digital World, Lori Andrews Apr 2017

Ispy: Threats To Individual And Institutional Privacy In The Digital World, Lori Andrews

Lori B. Andrews

What type of information is collected, who is viewing it, and what law librarians can do to protect their patrons and institutions.


Assessing Public Health Burden Associated With Exposure To Ambient Black Carbon In The United States, Ying Li, Daven K. Henze, Darby Jack, Barron H. Henderson, Patrick L. Kinney Apr 2017

Assessing Public Health Burden Associated With Exposure To Ambient Black Carbon In The United States, Ying Li, Daven K. Henze, Darby Jack, Barron H. Henderson, Patrick L. Kinney

Ying Li

Black carbon (BC) is a significant component of fine particulate matter (PM2.5) air pollution, which has been linked to a series of adverse health effects, in particular premature mortality. Recent scientific research indicates that BC also plays an important role in climate change. Therefore, controlling black carbon emissions provides an opportunity for a double dividend. This study quantifies the national burden of mortality and morbidity attributable to exposure to ambient BC in the United States (US). We use GEOS–Chem, a global 3-D model of atmospheric composition to estimate the 2010 annual average BC levels at 0.5 x 0.667° resolution, and …


Sidz Dc Article April Twenty, Sidney Twentythree Sr., Ann Test Apr 2017

Sidz Dc Article April Twenty, Sidney Twentythree Sr., Ann Test

Ann Test

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Mathematical Model Of The Shell With The Infill For Retaining Structures, Alexander T. Bekker, Nikita Ya. Tsimbelman, Dmitriy A. Potyanikhin, Andrey I. Mamontov, Ömer Bilgin, Tatiana I. Chernova Apr 2017

Mathematical Model Of The Shell With The Infill For Retaining Structures, Alexander T. Bekker, Nikita Ya. Tsimbelman, Dmitriy A. Potyanikhin, Andrey I. Mamontov, Ömer Bilgin, Tatiana I. Chernova

Ömer Bilgin

A description of finite element model and analysis of a shell with an infill is performed. A large diameter thin cylindrical shell structure with the edge leaning against compressible foundation soil is analyzed. Different materials are considered individually for the models of each structure shell and infill component (metal or reinforced concrete shell, and granular or elastic infill in a shell and foundation soil loaded by the structure). Contact conditions between 1) the infill and the shell’s inner surface and 2) between the foundation material and the shell edge are analyzed. An example of calculating strain conditions in the shell …


Wire Diffraction Gratings, Tom Greenslade Apr 2017

Wire Diffraction Gratings, Tom Greenslade

Thomas B. Greenslade, Jr.

No abstract provided.


Winter Rye Cover Crop Biomass Production, Degradation, And N Recycling, J. L. Pantoja, J. E. Sawyer, D. W. Barker Apr 2017

Winter Rye Cover Crop Biomass Production, Degradation, And N Recycling, J. L. Pantoja, J. E. Sawyer, D. W. Barker

John E. Sawyer

Winter rye (Secale cereale L.) as a cover crop can take up residual inorganic N between annual row crops and therefore be used to help reduce NO3 -–N loss from fields and movement to water systems. However, does the rye N uptake affect N recycling to soil and add to plant available N? The rye carbon:nitrogen (C:N) ratio could also influence N recycling. The objectives of this study were to evaluate rye biomass degradation and N recycling after spring rye termination in a no-till corn (Zea mays L.) - soybean [Glycine max. (L.) Merr.] rotation. A two year experiment (2010-2011) …