Stability analysis of an F/A-18 E/F cable mount m odel

A full-span F/A-18 E/F cable mounted wind tunnel model is part of a flutter clearance program at the NASA Langley Transonic Dynamics Tunnel. Parametric analysis of this model using GRUMCBL software was conducted to assess stability for wind tunnel tests. Two configurations of the F/A-18 E/F were examined. The parameters examined were pulley-cable friction, mach number, dynamic pressure, cable geometry, center of gravity location, cable tension, snubbing the model, drag, and test medium. For the nominal cable geometry (Cable Geometry 1), Configuration One was unstable for cases with higher pulley-cable friction coefficients. A new cable geometry (Cable Geometry 3) was determined in which Configuration One was stable for all cases evaluated. Configuration Two with the nominal center of gravity position was found to be unstable for cases with higher pulley-cable friction coefficients; however, the model was stable when the center of gravity moved forward 1/2. The model was tested using the cable mount system during the initial wind tunnel entry and was stable as predicted

The Quantum Tortoise and the Classical Hare: A simple framework for understanding which problems quantum computing will accelerate (and which it will not)

Quantum computing promises transformational gains for solving some problems, but little to none for others. For anyone hoping to use quantum computers now or in the future, it is important to know which problems will benefit. In this paper, we introduce a framework for answering this question both intuitively and quantitatively. The underlying structure of the framework is a race between quantum and classical computers, where their relative strengths determine when each wins. While classical computers operate faster, quantum computers can sometimes run more efficient algorithms. Whether the speed advantage or the algorithmic advantage dominates determines whether a problem will benefit from quantum computing or not. Our analysis reveals that many problems, particularly those of small to moderate size that can be important for typical businesses, will not benefit from quantum computing. Conversely, larger problems or those with particularly big algorithmic gains will benefit from near-term quantum computing. Since very large algorithmic gains are rare in practice and theorized to be rare even in principle, our analysis suggests that the benefits from quantum computing will flow either to users of these rare cases, or practitioners processing very large data

Educational Technology-Benefits and Barriers

Statement of Problem: The second background paper for the Medical School Objective Project (MSOP), defined Educational Technology (ET) as the use of information technology to facilitate student’s learning.1 Medical schools as a group have made limited progress in accomplishing the recommended educational technology goals and there had been much greater use of such technology in basic sciences courses than in clinical clerkships. We will explore the positive and negative implications of incorporating ET into the educational experience of TMC schools. [See PDF for complete abstract

Deceleration and Dispersion of Large-scale Coronal Bright Fronts

One of the most dramatic manifestations of solar activity are large-scale coronal bright fronts (CBFs) observed in extreme ultraviolet (EUV) images of the solar atmosphere. To date, the energetics and kinematics of CBFs remain poorly understood, due to the low image cadence and sensitivity of previous EUV imagers and the limited methods used to extract the features. In this paper, the trajectory and morphology of CBFs was determined in order to investigate the varying properties of a sample of CBFs, including their kinematics and pulse shape, dispersion, and dissipation. We have developed a semi-automatic intensity profiling technique to extract the morphology and accurate positions of CBFs in 2.5-10 min cadence images from STEREO/EUVI. The technique was applied to sequences of 171A and 195A images from STEREO/EUVI in order to measure the wave properties of four separate CBF events. Following launch at velocities of ~240-450kms^{-1} each of the four events studied showed significant negative acceleration ranging from ~ -290 to -60ms^{-2}. The CBF spatial and temporal widths were found to increase from ~50 Mm to ~200 Mm and ~100 s to ~1500 s respectively, suggesting that they are dispersive in nature. The variation in position-angle averaged pulse-integrated intensity with propagation shows no clear trend across the four events studied. These results are most consistent with CBFs being dispersive magnetoacoustic waves.Comment: 15 pages, 18 figure

Increasing Food Production in Drylands Using Agrivoltaics

In the desert, native plants respond to the hottest part of the day by either closing their stomata, which would stop photosynthesis, or by simply reducing their photosynthesis rates due to heat stress. Soil water resources are also impacted due to significant evaporation. If plants have more shade during the day, will they photosynthesize more in the afternoon than plants without shade? Will these plants with shade transpire less, and thus need to be watered less? This study takes a look at plants which have grown under a photovoltaics array (a new agriculture practice called agrivoltaics) as well as plants which have grown in the open (modeling traditional agriculture practices). It was hypothesized the agrivoltaics practice will benefit plants by providing them shade and retaining soil moisture during the day as well as benefiting the photovoltaics by keeping them cooler to increase their efficiency. This study was designed to determine whether growing under the photovoltaic panels is beneficial, by collecting and analyzing data on photosynthesis (carbon uptake) and transpiration (water loss) rates of 8+ different species. These measurements will help answer which plants are best suited for being planted in an agrivoltaics installation

Postgraduate Palliative care education: Evaluation of a South African Programme

AIM: We aimed to assess the postgraduate palliative care distance education programme of the University of Cape Town (UCT) in terms of its perceived ability to influence palliative care delivery. METHODS: A mixed-methods approach, consisting of two surveys using open-ended and multiple-choice options, was conducted from January to December 2007 at the UCT School of Public Health and Family Medicine. All students registered in the programme from 2000 - 2007 were invited to participate; 83 (66.4% of all eligible participants) completed the general survey, and 41 (65.7%) of the programme's graduates completed the graduate survey. The survey scores and open-ended data were triangulated to evaluate UCT's palliative care postgraduate programme. RESULTS: General survey scores of graduates were significantly higher in 5 of the 6 categories in comparison with current students. The graduate survey indicated that curriculum and teaching strengths were in communication and dealing with challenging encounters. Graduates also stressed the need to develop a curriculum that incorporated a practical component. CONCLUSIONS: In addition to current postgraduate training, palliative care education in South Africa should be extended to undergraduate medical students, as the benefits of UCT's programme were limited to a small cohort of practitioners

Postgraduate palliative care education: Evaluation of a South African programme

Aim. We aimed to assess the postgraduate palliative care distance education programme of the University of Cape Town (UCT) in terms of its perceived ability to influence palliative care delivery. Methods. A mixed-methods approach, consisting of two surveys using open-ended and multiple-choice options, was conducted from January - December 2007 at the UCT School of Public Health and Family Medicine. All students registered in the programme from 2000 - 2007 were invited to participate; 83 (66.4% of all eligible participants) completed the general survey, and 41 (65.7%) of the programme's graduates completed the graduate survey. The survey scores and open-ended data were triangulated to evaluate UCT’s palliative care postgraduate programme. Results. General survey scores of graduates were significantly higher in 5 of the 6 categories in comparison with current students. The graduate survey indicated that curriculum and teaching strengths were in communication and dealing with challenging encounters. Graduates also stressed the need to develop a curriculum that incorporated a practical component. Conclusions. In addition to current postgraduate training, palliative care education in South Africa should be extended to undergraduate medical students, as the benefits of UCT’s programme were limited to a small cohort of practitioners

Prison Gerrymandering Report 2021

The purpose of the redistricting process should be to create districts that accurately reflect the communities they represent and to distribute political power across those communities. But counting incarcerated individuals at the facility where they are incarcerated, rather than their home addresses, artificially bolsters the political power of certain communities on the backs of individuals who are not truly part of those communities, while simultaneously reducing the political voices of their home communities. In Texas, there are dramatic implications, with a handful of rural regions gaining a disproportionate share of the political power over other rural regions and diminishing the true population count in certain urban areas. This under-representation only exacerbates existing problems with Census undercounts and socio economic disparities which have a root in racial discrimination. It also deviates from how Texas law treats incarcerated populations in every other context, creating a conflict with the Texas constitution that needs to be addressed.Traditionally, the United States Census Bureau has counted incarcerated individuals at the facility where they are housed, but the Bureau has made clear that this historical practice has persisted only for administrative reasons, not for legal or policy ones. Recently, the Census Bureau has evolved in its treatment of incarcerated populations, and, for the first time, will make it practical for states on tight timelines to assign incarcerated individuals to their home communities. Many states across the nation are taking advantage of this opportunity to correct for the distortions created by prison gerrymandering. In order to more accurately reflect the state's population, Texas legislators should take advantage of the Census Bureau's new tools and work with state agencies to identify those prisoners who, rightfully, should be counted at an address in their permanent community