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Marbles: The Application Of Input-Output Concepts To Safety Management Systems, Tim Brady, A. Stolzer, Anthony Brickhouse, Antonio Cortes, Dan Mccune, Jayathi Raghavan, David Freiwald Jan 2015

Marbles: The Application Of Input-Output Concepts To Safety Management Systems, Tim Brady, A. Stolzer, Anthony Brickhouse, Antonio Cortes, Dan Mccune, Jayathi Raghavan, David Freiwald

Publications

The goal of this research was to apply the economic concept titled Input-Output Analysis to an aviation safety concept titled Safety Management Systems (SMS). Input-Output (IO) is based upon the interrelationships of various components of an economic system and what happens to the system when one or more of those components changes. Since SMS is, by definition, a system with definable components, the research sought to determine if the interrelationships between those components could be determined and quantified. The term ‘‘marbles’’ was used to describe the activities that led to the IO-SMS matrix. Marbles was used as a metaphor for …


Mitigating The Effects Of Climate Change With Wind Energy And Gis, Rachael Isphording, Richard Snow, Mary Snow Dec 2014

Mitigating The Effects Of Climate Change With Wind Energy And Gis, Rachael Isphording, Richard Snow, Mary Snow

Publications

The climate is changing, and humans are heavily exacerbating these changes. As the effects of climate change are being felt across the planet, scientists and policy makers are uniting to increase mitigation efforts and are researching renewable, clean energy sources to reduce the amount of greenhouse gas emissions released into the atmosphere during energy production. Of the different renewable energy technologies, wind energy is one of the most researched and implemented. Over the past twenty years, researchers have been applying Geographic Information Systems (GIS) to their climate change studies. GIS allows the user to spatially view, manipulate, and analyze data …


Ethics Is Not Rocket Science: How To Have Ethical Discussions In Your Science Class, Kelly C. Smith Dec 2014

Ethics Is Not Rocket Science: How To Have Ethical Discussions In Your Science Class, Kelly C. Smith

Publications

The Rutland Institute for Ethics at Clemson University seeks to encourage discussion on campus, in businesses, and in the community about how ethical decision-making can be the basis of both personal and professional success. In the last 15 years, our fellows have, among other things, served as Co-PI’s on a wide range of grants, produced Responsible Conduct of Research training for science and engineering graduate students and faculty, managed the ethics curriculum at a medical school, and produced video lectures on ethical thinking for undergraduate Biology majors. The crown jewel of our efforts to-date is our Ethics Across the Curriculum …


Engineering Design Challenge, Lindsay B. Wheeler, Brooke A. Whitworth, Amanda L. Gonczi Dec 2014

Engineering Design Challenge, Lindsay B. Wheeler, Brooke A. Whitworth, Amanda L. Gonczi

Publications

No abstract provided.


A Deep Proper Motion Catalog Within The Sloan Digital Sky Survey Footprint, Jeffrey A. Munn, Hugh C. Harris, Ted Von Hippel, Mukremin Kilic, James W. Liebert, Kurtis A. Williams, Steven Degenarro, Elizabeth Jeffery, Trudy M. Tilleman Dec 2014

A Deep Proper Motion Catalog Within The Sloan Digital Sky Survey Footprint, Jeffrey A. Munn, Hugh C. Harris, Ted Von Hippel, Mukremin Kilic, James W. Liebert, Kurtis A. Williams, Steven Degenarro, Elizabeth Jeffery, Trudy M. Tilleman

Publications

A new proper motion catalog is presented, combining the Sloan Digital Sky Survey (SDSS) with second epoch observations in the r band within a portion of the SDSS imaging footprint. The new observations were obtained with the 90prime camera on the Steward Observatory Bok 90 inch telescope, and the Array Camera on the U.S. Naval Observatory, Flagstaff Station, 1.3 m telescope. The catalog covers 1098 square degrees to r = 22.0, an additional 1521 square degrees to r = 20.9, plus a further 488 square degrees of lesser quality data. Statistical errors in the proper motions range from 5 mas …


The Power Of Principled Bayesian Methods In The Study Of Stellar Evolution, Ted Von Hippel, David Van Dyk, David Stenning, Elliot Robinson, Elizabeth Jeffery, Nathan Stein, William Jefferys, Erin M. O'Malley Nov 2014

The Power Of Principled Bayesian Methods In The Study Of Stellar Evolution, Ted Von Hippel, David Van Dyk, David Stenning, Elliot Robinson, Elizabeth Jeffery, Nathan Stein, William Jefferys, Erin M. O'Malley

Publications

It takes years of effort employing the best telescopes and in- struments to obtain high-quality stellar photometry, astrometry, and spectroscopy. Stellar evolution models contain the experience of life- times of theoretical calculations and testing. Yet most astronomers fit these valuable models to these precious datasets by eye. We show that a principled Bayesian approach to fitting models to stellar data yields substantially more information over a range of stellar astrophysics. We highlight advances in determining the ages of star clusters, mass ratios of binary stars, limitations in the accuracy of stellar models, post-main-sequence mass loss, and the ages of individual …


Bayesian Analysis For Stellar Evolution With Nine Parameters (Base-9): User's Manual, Ted Von Hippel, Elliot Robinson, Elizabeth Jeffery, Rachel Wagner-Kaiser, Steven Degennaro, Nathan Stein, David Stenning, William H. Jefferys, David Van Dyk Nov 2014

Bayesian Analysis For Stellar Evolution With Nine Parameters (Base-9): User's Manual, Ted Von Hippel, Elliot Robinson, Elizabeth Jeffery, Rachel Wagner-Kaiser, Steven Degennaro, Nathan Stein, David Stenning, William H. Jefferys, David Van Dyk

Publications

BASE-9 is a Bayesian software suite that recovers star cluster and stellar parameters from photometry. BASE-9 is useful for analyzing single-age, single-metallicity star clusters, binaries, or single stars, and for simulating such systems. BASE-9 uses Markov chain Monte Carlo and brute-force numerical integration techniques to estimate the posterior probability distributions for the age, metallicity, helium abundance, distance modulus, and line-of-sight absorption for a cluster, and the mass, binary mass ratio, and cluster membership probability for every stellar object. BASE-9 is provided as open source code on a version-controlled web server. The executables are also available as Amazon Elastic Compute Cloud …


Manifest Complexity: A Foundational Ethic For Astrobiology?, Kelly C. Smith Nov 2014

Manifest Complexity: A Foundational Ethic For Astrobiology?, Kelly C. Smith

Publications

This paper examines the age old question of the basis of moral value in the new context of astrobiology, which offers a fresh perspective. The goal is to offer the broad outline of a general theory of moral value that can accommodate the diversity of living entities we are likely to encounter beyond the confines of Earth. It begins with ratiocentrism, the view that the possession of reason is the primary means by which we differentiate entities having moral value in and of themselves from those having moral value merely by virtue of the uses to which they can be …


Book Review: Planetary Rings: A Post-Equinox View 2nd Ed, T. D. Oswalt Nov 2014

Book Review: Planetary Rings: A Post-Equinox View 2nd Ed, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Planetary Rings : a Post-Equinox View 2nd Ed. by Larry W. Esposito, Cambridge, 2014 246p bibl index, 9781107028821 $120.00


Numerical Simulation Of The Long-Range Propagation Of Gravity Wave Packets At High Latitudes, C. J. Heale, J. B. Snively, M. P. Hickey Oct 2014

Numerical Simulation Of The Long-Range Propagation Of Gravity Wave Packets At High Latitudes, C. J. Heale, J. B. Snively, M. P. Hickey

Publications

We use a 2-D, nonlinear, time-dependent numerical model to simulate the propagation of wave packets under average high latitude, winter conditions. We investigate the ability of waves to propagate large horizontal distances, depending on their direction of propagation relative to the average modeled ambient winds. Wave sources were specified to represent the following: (1) the most common wave parameters inferred from observations of Nielsen et al. (2009) ((18 km λᵪ , 7.5 min period), (2) waves consistent with the average phase speed observed (40 m/s) but outlying horizontal wavelength and period values (40 km λᵪ , 17 min period), and …


Improving Tennis Player Performance Using System Development Interpretations Methodology, Dotan Shvorin, Kevin Taaffe Oct 2014

Improving Tennis Player Performance Using System Development Interpretations Methodology, Dotan Shvorin, Kevin Taaffe

Publications

This research demonstrates a unique analytical approach to improving a player's performance in the game of tennis. We introduce a system development interpretations (SDI) methodology for associating player characteristics and factors in a hierarchical structure. We then show how this tool is applied in a human performance environment such as tennis. This approach was developed as a multi-disciplinary quality tool for process improvement that identifies factor dependencies and depicts their impact on the resulting player performance. From the implementation of the SDI methodology, the research was able to define the tennis player's difficulties and it has allowed the researchers to …


Benchmarking Professional Development Practices Across Youth-Serving Organizations: Implications For Extension, Barry A. Garst, Sarah Baughman, Nancy Franz Oct 2014

Benchmarking Professional Development Practices Across Youth-Serving Organizations: Implications For Extension, Barry A. Garst, Sarah Baughman, Nancy Franz

Publications

Examining traditional and contemporary professional development practices of youth-serving organizations can inform practices across Extension, particularly in light of the barriers that have been noted for effectively developing the professional competencies of Extension educators. With professional development systems changing quickly, particularly through online education and blended learning opportunities, benchmarks need to guide new research around best practices in professional development. Although many program providers have not established benchmarks for professional development, a few cases exist. This article examines the current state of professional development practices of youth-serving organizations and offers recommendations for improving Extension professional development practices.


Synthetic Data Generation For The Internet Of Things, Jason Anderson, K. E. Kennedy, Linh B. Ngo, Andre Luckow, Amy Apon Oct 2014

Synthetic Data Generation For The Internet Of Things, Jason Anderson, K. E. Kennedy, Linh B. Ngo, Andre Luckow, Amy Apon

Publications

The concept of Internet of Things (IoT) is rapidly moving from a vision to being pervasive in our everyday lives. This can be observed in the integration of connected sensors from a multitude of devices such as mobile phones, healthcare equipment, and vehicles. There is a need for the development of infrastructure support and analytical tools to handle IoT data, which are naturally big and complex. But, research on IoT data can be constrained by concerns about the release of privately owned data. In this paper, we present the design and implementation results of a synthetic IoT data generation framework. …


Rational Design Of Small-Molecule Stabilizers Of Spermine Synthase Dimer By Virtual Screening And Free Energy-Based Approach, Zhe Zhang, Virginie Martiny, David Lagorce, Yoshihiko Ikeguchi, Emil Alexov, Maria A. Miteva Oct 2014

Rational Design Of Small-Molecule Stabilizers Of Spermine Synthase Dimer By Virtual Screening And Free Energy-Based Approach, Zhe Zhang, Virginie Martiny, David Lagorce, Yoshihiko Ikeguchi, Emil Alexov, Maria A. Miteva

Publications

Snyder-Robinson Syndrome (SRS) is a rare mental retardation disorder which is caused by the malfunctioning of an enzyme, the spermine synthase (SMS), which functions as a homo-dimer. The malfunctioning of SMS in SRS patients is associated with several identified missense mutations that occur away from the active site. This investigation deals with a particular SRS-causing mutation, the G56S mutation, which was shown computationally and experimentally to destabilize the SMS homo-dimer and thus to abolish SMS enzymatic activity. As a proof-of-concept, we explore the possibility to restore the enzymatic activity of the malfunctioning SMS mutant G56S by stabilizing the dimer through …


Shifted One-Parameter Supersymmetric Family Of Quartic Asymmetric Double-Well Potentials, Haret C. Rosu, S.C. Mancas, Pisin Chen Oct 2014

Shifted One-Parameter Supersymmetric Family Of Quartic Asymmetric Double-Well Potentials, Haret C. Rosu, S.C. Mancas, Pisin Chen

Publications

Extending our previous work (Rosu, Mancas, Chen, Ann.Phys. 343 (2014) 87-102), we define supersymmetric partner potentials through a particular Riccati solution of the form F (x) = (x - c)^2 - 1, where c is a real shift parameter, and work out the quartic double-well family of one-parameter isospectral potentials obtained by using the corresponding general Riccati solution. For these parametric double well potentials, we study how the localization properties of the two wells depend on the parameter of the potentials for various values of the shifting parameter.


Energy Consumption Reduction Strategies For Plug-In Hybrid Electric Vehicles With Connected Vehicle Technology In An Urban Environment, Parth Bhavsar, Yiming He, Mashrur Chowdhury, Ryan Fries, Andrew Shealy Sep 2014

Energy Consumption Reduction Strategies For Plug-In Hybrid Electric Vehicles With Connected Vehicle Technology In An Urban Environment, Parth Bhavsar, Yiming He, Mashrur Chowdhury, Ryan Fries, Andrew Shealy

Publications

Automobile manufacturers have introduced plug-in hybrid electric vehicles (PHEVs) to reduce fossil fuel consumption. This paper details three optimization strategies that can be utilized to further minimize energy consumption of PHEVs through an information exchange between PHEVs and infrastructure agents supported by the connected vehicle technology (CVT). While an earlier research by the authors focused on a freeway scenario, this study developed strategies for an urban scenario in which frequent ‘stop-and-go’ conditions exist. Three strategies were considered in this study based on different types of information availability using CVT; only signal timing information was available in Strategy One, only headway …


Fitting Multiple Bell Curves Stably And Accurately To A Time Series As Applied To Hubbert Cycles Or Other Phenomena, James A. Conder Sep 2014

Fitting Multiple Bell Curves Stably And Accurately To A Time Series As Applied To Hubbert Cycles Or Other Phenomena, James A. Conder

Publications

Bell curves are applicable to understating many observations and measurements across the sciences. Relating Gaussian curves to data is a common because of its relation to both the Central Limit Theorem and to random error. Similarly, fitting logistic derivatives to oil or other nonrenewable resource production is common practice. Fitting bell curves to a time series is an inherently non-linear problem requiring initial estimates of the parameters describing the bellcurves. Poor estimates lead to instability and divergent solutions. Fitting to a cumulative curve improves stability, but at the expense of accuracy of the final solution. Jointly fitting multiple bell curves …


On Uav Robust Nonlinear Control In Presence Of Parametric Uncertainties, Vladimir V. Golubev, William Mackunis Sep 2014

On Uav Robust Nonlinear Control In Presence Of Parametric Uncertainties, Vladimir V. Golubev, William Mackunis

Publications

We examine a new robust nonlinear flight control technology that employs an array of synthetic-jet micro-actuators embedded in UAV wing design in order to completely eliminate moving parts (such as ailerons) thus greatly enhancing maneuverability required for small fixed-wing air vehicles operating, e.g., in tight urban environments. Estimated fast response times are critical in mitigating gust effects while greatly improving flight stability and control. The new controller design is particularly advantageous for high levels of uncertainty and nonlinearity present both in the unsteady flowpath environment and in the embedded actuator’s response. The current work focuses on a benchmark case of …


Investigation Of A Mesospheric Gravity Wave Ducting Event Using Coordinated Sodium Lidar And Mesospheric Temperature Mapper Measurements At Alomar, Norway (69°N), Katrina Bossert, David C. Fritts, Pierre-Dominique Pautet, Michael J. Taylor, Bifford P. Williams, William R. Pendleton Jr. Aug 2014

Investigation Of A Mesospheric Gravity Wave Ducting Event Using Coordinated Sodium Lidar And Mesospheric Temperature Mapper Measurements At Alomar, Norway (69°N), Katrina Bossert, David C. Fritts, Pierre-Dominique Pautet, Michael J. Taylor, Bifford P. Williams, William R. Pendleton Jr.

Publications

New measurements at the ALOMAR observatory in northern Norway (69°N, 16°E) using the Weber sodium lidar and the Advanced Mesospheric Temperature Mapper (AMTM) allow for a comprehensive investigation of a gravity wave (GW) event on 22 and 23 January 2012 and the complex and varying propagation environment in which the GW was observed. These observational techniques provide insight into the altitude ranges over which a GW may be evanescent or propagating and enable a clear distinction in specific cases. Weber sodium lidar measurements provide estimates of background temperature, wind, and stability profiles at altitudes from ~78 to 105 km. Detailed …


A Coordinated Investigation Of The Gravity Wave Breaking And The Associated Dynamical Instability By A Na Lidar And An Advanced Mesosphere Temperature Mapper Over Logan, Ut (41.7°N, 111.8°W), Xuguang Cai, Tao Yuan, Yucheng Zhao, Pierre-Dominique Pautet, Michael J. Taylor, William R. Pendleton Jr. Aug 2014

A Coordinated Investigation Of The Gravity Wave Breaking And The Associated Dynamical Instability By A Na Lidar And An Advanced Mesosphere Temperature Mapper Over Logan, Ut (41.7°N, 111.8°W), Xuguang Cai, Tao Yuan, Yucheng Zhao, Pierre-Dominique Pautet, Michael J. Taylor, William R. Pendleton Jr.

Publications

The impacts of gravity wave (GW) on the thermal and dynamic characteristics within the mesosphere/lower thermosphere, especially on the atmospheric instabilities, are still not fully understood. In this paper, we conduct a comprehensive and detailed investigation on one GW breaking event during a collaborative campaign between the Utah State University Na lidar and the Advanced Mesospheric Temperature Mapper (AMTM) on 9 September 2012. The AMTM provides direct evidence of the GW breaking as well as the horizontal parameters of the GWs involved, while the Na lidar's full diurnal cycle observations are utilized to uncover the roles of tide and GWs …


Potential And Technological Advancement Of Biofuels, Rajee Olaganathan, Fabian Ko Qui Shen, Lim Jun Shen Aug 2014

Potential And Technological Advancement Of Biofuels, Rajee Olaganathan, Fabian Ko Qui Shen, Lim Jun Shen

Publications

This scientific paper examines the feasibility of biofuels as a solution to the world‟s energy crisis. It studies the development of the four different generations of biofuel that have been discerned over the years, determining the pros and cons of each. The paper further investigates the issues concerning each generation, and determines how their successors have solved and improved on those problems. In order to give the reader an unbiased perspective, the paper studies both general advantages and disadvantages that encompasses social, economic and environmental impacts. Research and development on the first two generations of biofuels have matured, and case …


The Geocoronal H Α Cascade Component Determined From Geocoronal H Β Intensity Measurements, F. L. Roesler, E. J. Mierkiewicz, S. M. Nossal Aug 2014

The Geocoronal H Α Cascade Component Determined From Geocoronal H Β Intensity Measurements, F. L. Roesler, E. J. Mierkiewicz, S. M. Nossal

Publications

"Geocoronal H α and H β intensity measurements using the Wisconsin H α Mapper Fabry-Perot are used to determine the intensity of the H α cascade component. From basic atomic physics and the work of Meier (1995), we show that the total cascade in geocoronal H α emission is 0.52 ± 0.03 times the geocoronal H β intensity, I(H β), for solar Lyman series excitation of geocoronal hydrogen. The results are consistent with the H α cascade measurements of Mierkiewicz et al. (2012), which were determined directly from the analysis of H α line profile measurements, and significantly narrow the …


A Statistical Study Of Magnetic Field Fluctuations In The Dayside Magnetosheath And Their Dependence On Upstream Solar Wind Conditions, A. P. Dimmock, K. Nykyri, T. I. Pulkkinen Aug 2014

A Statistical Study Of Magnetic Field Fluctuations In The Dayside Magnetosheath And Their Dependence On Upstream Solar Wind Conditions, A. P. Dimmock, K. Nykyri, T. I. Pulkkinen

Publications

The magnetosheath functions as a natural interface connecting the interplanetary and magnetospheric plasma. Since the magnetosheath houses the shocked solar wind, it is populated with abundant magnetic field turbulence which are generated both locally and externally. Although the steady state magnetosheath is to date relatively well understood, the same cannot be said of transient magnetic perturbations due to their kinetic nature and often complex and numerous generation mechanisms. The current manuscript presents a statistical study of magnetic field fluctuations in the dayside magnetosheath as a function of upstream solar wind conditions. We concentrate on the ambient higher-frequency fluctuations in the …


Nonadiabatic Heating In Magnetic Reconnection, Xuanye Ma, Antonius Otto Jul 2014

Nonadiabatic Heating In Magnetic Reconnection, Xuanye Ma, Antonius Otto

Publications

Plasma transport process as a fundamental problem in magnetospheric physics is often associated with strong nonadiabatic heating. At the magnetopause, observations show an increase of specific entropy (i.e., S = p/ργ) by 2 orders of magnitude from the magnetosheath into the magnetosphere. In the near‐Earth magnetotail, particle injection requires strongly entropy depleted plasma bubbles, and their evolution can be strongly modified in the presence of nonadiabatic heating. In this study, one of the critical plasma transport mechanisms, magnetic reconnection, is investigated as a nonadiabatic process in the framework of MHD. It is important to examine whether magnetic reconnection can provide …


Variable Viscosity Condition In The Modeling Of A Slider Bearing, Kedar Nath Uprety, S.C. Mancas Jul 2014

Variable Viscosity Condition In The Modeling Of A Slider Bearing, Kedar Nath Uprety, S.C. Mancas

Publications

To reduce tear and wear of machinery lubrication is essential. Lubricants form a layer between two surfaces preventing direct contact and reduce friction between moving parts and hence reduce wear. In this short letter the lubrication of two slider bearings with parallel and nonparallel is studied. First, we show that bearings with parallel plates cannot support any load. For bearings with nonparallel plates we are interested on how constant and temperature dependent viscosity affects the properties of the bearings. Also, a critical temperature for which the bearings would fail due to excess in temperature is found for both latter cases. …


Problm Web Server: Protein And Membrane Placement And Orientation Package, Taylor Kimmett, Nicholas Smith, Shawn Witham, Marharyta Petukh, Subhra Sarkar, Emil Alexov Jul 2014

Problm Web Server: Protein And Membrane Placement And Orientation Package, Taylor Kimmett, Nicholas Smith, Shawn Witham, Marharyta Petukh, Subhra Sarkar, Emil Alexov

Publications

The 3D structures of membrane proteins are typically determined without the presence of a lipid bilayer. For the purpose of studying the role of membranes on the wild type characteristics of the corresponding protein, determining the position and orientation of transmembrane proteins within a membrane environment is highly desirable. Here we report a geometry-based approach to automatically insert a membrane protein with a known 3D structure into pregenerated lipid bilayer membranes with various dimensions and lipid compositions or into a pseudomembrane. The pseudomembrane is built using the Protein Nano-Object Integrator which generates a parallelepiped of user-specified dimensions made up of …


The Life Cycle Of Instability Features Measured From The Andes Lidar Observatory Over Cerro Pachon On 24 March 2012, J. H. Hecht, K. Wan, L. J. Gelinas, David C. Fritts, R. L. Walterscheid, R. J. Rudy, A. Z. Liu, S. J. Franke, F. A. Vargas, Pierre-Dominique Pautet, Michael J. Taylor, G. R. Swenson Jun 2014

The Life Cycle Of Instability Features Measured From The Andes Lidar Observatory Over Cerro Pachon On 24 March 2012, J. H. Hecht, K. Wan, L. J. Gelinas, David C. Fritts, R. L. Walterscheid, R. J. Rudy, A. Z. Liu, S. J. Franke, F. A. Vargas, Pierre-Dominique Pautet, Michael J. Taylor, G. R. Swenson

Publications

The Aerospace Corporation's Nightglow Imager (ANI) observes nighttime OH emission (near 1.6 μm) every 2 s over an approximate 73° field of view. ANI had previously been used to study instability features seen over Maui. Here we describe observations of instabilities seen from 5 to 8 UT on 24 March 2012 over Cerro Pachon, Chile, and compare them with previous results from Maui, with theory, and with Direct Numerical Simulations (DNS). The atmosphere had reduced stability because of the large negative temperature gradients measured by a Na lidar. Thus, regions of dynamical and convective instabilities are expected to form, depending …


Should Expectations About The Rate Of New Antiretroviral Drug Development Impact The Timing Of Hiv Treatment Initiation And Expectations About Treatment Benefits?, Amin Khademi, R. Scott Braithwaite, Denis Saure, Andrew J. Schaefer, Kimberly Nucifora, Mark S. Roberts Jun 2014

Should Expectations About The Rate Of New Antiretroviral Drug Development Impact The Timing Of Hiv Treatment Initiation And Expectations About Treatment Benefits?, Amin Khademi, R. Scott Braithwaite, Denis Saure, Andrew J. Schaefer, Kimberly Nucifora, Mark S. Roberts

Publications

Background: Many analyses of HIV treatment decisions assume a fixed formulary of HIV drugs. However, new drugs are approved nearly twice a year, and the rate of availability of new drugs may affect treatment decisions, particularly when to initiate antiretroviral therapy (ART).

Objectives: To determine the impact of considering the availability of new drugs on the optimal initiation criteria for ART and outcomes in patients with HIV/AIDS.

Methods: We enhanced a previously described simulation model of the optimal time to initiate ART to incorporate the rate of availability of new antiviral drugs. We assumed that the future rate of availability …


High-Resolution Spectroscopy Of The Lunar Sodium Exosphere, E. J. Mierkiewicz, R. J. Oliversen, F. L. Roesler, O. L. Lupie Jun 2014

High-Resolution Spectroscopy Of The Lunar Sodium Exosphere, E. J. Mierkiewicz, R. J. Oliversen, F. L. Roesler, O. L. Lupie

Publications

"We have applied high-resolution Fabry-Perot spectroscopy to the study of the lunar sodium exosphere for the study of exospheric effective temperature and velocity variations. Observing from the National Solar Observatory McMath-Pierce Telescope, we used a dual-etalon Fabry-Perot spectrometer with a resolving power of 180,000 to measure line widths and Doppler shifts of the sodium D2 (5889.95 Å) emission line. Our field of view was 360 km, and measurements were made in equatorial and polar regions from 500 km to 3500 km off the limb. Data were obtained from full moon to 3 days following full moon (waning phase) in March …


Ermakov-Lewis Invariants And Reid Systems, S.C. Mancas, Haret C. Rosu Jun 2014

Ermakov-Lewis Invariants And Reid Systems, S.C. Mancas, Haret C. Rosu

Publications

Reid's mth-order generalized Ermakov systems of nonlinear coupling constant α are equivalent to an integrable Emden–Fowler equation. The standard Ermakov–Lewis invariant is discussed from this perspective, and a closed formula for the invariant is obtained for the higher-order Reid systems (m≥3). We also discuss the parametric solutions of these systems of equations through the integration of the Emden–Fowler equation and present an example of a dynamical system for which the invariant is equivalent to the total energy.