Three-track runway elevation profiles measured at two United States Government installations

Three-track airport runway elevation profiles and airplane response to runway roughnes

The NASA digital VGH program, early results

Data from airline digital flight data recorders provides relevant statistical data for estimating fatigue life consumption of the current airliner fleet and for design criteria updating for future designs. The data indicates real operating effects due to the autopilot, i.e., gust response frequency peak increase by 2 or 3 times, and the existence of the low frequency low amplitude limit cycle motion in altitude hold. The extension of more data types for ground operations is considered. Onboard processing of simple data types is also considered

Basic research in wake vortex alleviation using a variable twist wing

The variable twist wing concept was used to investigate the relative effects of lift and turbulence distribution on the rolled up vortex wake. Several methods of reducing the vortex strength behind an aircraft were identified. These involve the redistribution of lift spanwise on the wing and drag distribution along the wing. Initial attempts to use the variable twist wing velocity data to validate the WAKE computer code have shown a strong correlation, although the vorticity levels were not exactly matched

NASA thermionic-conversion program

Current out-of-core emphases allow converter material and design freedoms previously prohibited by in-core nucleonic and geometric restrictions. As a result, potential improvements indicate possibilities for severalfold increases in efficiencies. The new TEC-ART program concentrated initially on low-work function collectors and interelectrode-loss reduction and revealed much in a short time. This new emission capability coupled with improved collectors that maintain performance with emitter-vapor deposit accumulations are requisites for efficient, enduring thermionic converters

Development and evaluation of a prototype in-flight instrument flight rules (IFR) procedures trainer

An in-flight instrument flight rules (IFR) procedures trainer capable of providing simulated indications of instrument flight in a typical general aviation aircraft independent of ground based navigation aids was developed. The IFR navaid related instruments and circuits from an ATC 610J table top simulator were installed in a Cessna 172 aircraft and connected to its electrical power and pitot static systems. The benefits expected from this hybridization concept include increased safety by reducing the number of general aviation aircraft conducting IFR training flights in congested terminal areas, and reduced fuel use and instruction costs by lessening the need to fly to and from navaid equipped airports and by increased efficiency of the required in-flight training. Technical feasibility was demonstrated and the operational feasibility of the concept was evaluated. Results indicated that the in-flight simulator is an effective training device for teaching IFR procedural skills

A review of the NASA V-G/VGH general aviation program

The V-G and VGH data collected from a wide variety of general aviation airplanes since the inception of the NASA V-G/VGH General Aviation Program in 1962 are presented. These data were analyzed to obtain information on the gust and maneuver loads, on the operating practices, and on the effects of different types of operations on these parameters

Sensitivity of Nonrenormalizable Trajectories to the Bare Scale

Working in scalar field theory, we consider RG trajectories which correspond to nonrenormalizable theories, in the Wilsonian sense. An interesting question to ask of such trajectories is, given some fixed starting point in parameter space, how the effective action at the effective scale, Lambda, changes as the bare scale (and hence the duration of the flow down to Lambda) is changed. When the effective action satisfies Polchinski's version of the Exact Renormalization Group equation, we prove, directly from the path integral, that the dependence of the effective action on the bare scale, keeping the interaction part of the bare action fixed, is given by an equation of the same form as the Polchinski equation but with a kernel of the opposite sign. We then investigate whether similar equations exist for various generalizations of the Polchinski equation. Using nonperturbative, diagrammatic arguments we find that an action can always be constructed which satisfies the Polchinski-like equation under variation of the bare scale. For the family of flow equations in which the field is renormalized, but the blocking functional is the simplest allowed, this action is essentially identified with the effective action at Lambda = 0. This does not seem to hold for more elaborate generalizations.Comment: v1: 23 pages, 5 figures, v2: intro extended, refs added, published in jphy

Why stigma matters in addressing alcohol harm

Alcohol problems are amongst the most stigmatized of conditions, resulting in multiple additional harms for people with Alcohol Use Disorder (AUD). Alcohol stigma encompasses widely endorsed negative stereotypes leading to prejudice and discrimination towards people with AUD. Self-stigma further harms individuals through preventing and undermining recovery. The persistence of alcohol stigma highlights the limitations of an illness model of AUD for stigma reduction; in fact, many groups inadvertently reinforce stigma by emphasizing the artificial line between ‘normal’ drinkers and the pathologized ‘alcoholic other’. A public health case for alcohol stigma reduction highlights the need to address this societal false dichotomization of problem drinkers. Promoting a continuum aligned model of AUD, a dynamic model of responsibility, and other evidence-led approaches such as person-first language by key stakeholders are recommended

Chameleon effect and the Pioneer anomaly

The possibility that the apparent anomalous acceleration of the Pioneer 10 and 11 spacecraft may be due, at least in part, to a chameleon field effect is examined. A small spacecraft, with no thin shell, can have a more pronounced anomalous acceleration than a large compact body, such as a planet, having a thin shell. The chameleon effect seems to present a natural way to explain the differences seen in deviations from pure Newtonian gravity for a spacecraft and for a planet, and appears to be compatible with the basic features of the Pioneer anomaly, including the appearance of a jerk term. However, estimates of the size of the chameleon effect indicate that its contribution to the anomalous acceleration is negligible. We conclude that any inverse-square component in the anomalous acceleration is more likely caused by an unmodelled reaction force from solar-radiation pressure, rather than a chameleon field effect.Comment: 16 pages; to appear in Phys.Rev.

Web-based Tools for the Analysis of DNA Microarrays

End of project reportDNA microarrays are widely used for gene expression profiling. Raw data resulting from microarray experiments, however, tends to be very noisy and there are many sources of technical variation and bias. This raw data needs to be quality assessed and interactively preprocessed to minimise variation before statistical analysis in order to achieve meaningful result. Therefore microarray analysis requires a combination of visualisation and statistical tools, which vary depending on what microarray platform or experimental design is used.Bioconductor is an existing open source software project that attempts to facilitate analysis of genomic data. It is a collection of packages for the statistical programming language R. Bioconductor is particularly useful in analyzing microarray experiments. The problem is that the R programming language’s command line interface is intimidating to many users who do not have a strong background in computing. This often leads to a situation where biologists will resort to using commercial software which often uses antiquated and much less effective statistical techniques, as well as being expensively priced. This project aims to bridge this gap by providing a user friendly web-based interface to the cutting edge statistical techniques of Bioconductor