13,981 research outputs found

    Man's transportation to space

    Get PDF
    Saturn i, saturn ib, and saturn v launch vehicle

    Understanding reflective practice: encouraging better student engagement. First person action inquiry

    Get PDF
    The purpose of this research project is to examine my own engagement with reflective practice in my capacity as teacher and practitioner. This process of examination aims to improve attention to reflective practice within the student nutritional therapist environment where I teach. Research was conducted using a first-person action approach, with data acquired via critical self-observation and non-inquisitorial involvement in work-based situations feeding into action-reflection cycles. Conclusions highlighted strengths and areas for development as teacher and practitioner which may impact on student engagement with reflective practice on the course. Wider staff training and improvement to the curriculum were also identified with actions and recommendations including the adoption of new reflective practice teaching methods, further training for staff, adjustments to personal reflective practices and curriculum-wide developments. The proposed dissemination of findings and outcomes more widely will be via the nutritional therapy regulatory body and amongst fellow training providers

    Afterglow lightcurves, viewing angle and the jet structure of gamma-ray bursts

    Full text link
    Gamma ray bursts are often modelled as jet-like outflows directed towards the observer; the cone angle of the jet is then commonly inferred from the time at which there is a steepening in the power-law decay of the afterglow. We consider an alternative model in which the jet has a beam pattern where the luminosity per unit solid angle (and perhaps also the initial Lorentz factor) decreases smoothly away from the axis, rather than having a well-defined cone angle within which the flow is uniform. We show that the break in the afterglow light curve then occurs at a time that depends on the viewing angle. Instead of implying a range of intrinsically different jets - some very narrow, and others with similar power spread over a wider cone - the data on afterglow breaks could be consistent with a standardized jet, viewed from different angles. We discuss the implication of this model for the luminosity function.Comment: Corrected typo in Eq. 1

    Importance of an Astrophysical Perspective for Textbook Relativity

    Get PDF
    The importance of a teaching a clear definition of the ``observer'' in special relativity is highlighted using a simple astrophysical example from the exciting current research area of ``Gamma-Ray Burst'' astrophysics. The example shows that a source moving relativistically toward a single observer at rest exhibits a time ``contraction'' rather than a ``dilation'' because the light travel time between the source and observer decreases with time. Astrophysical applications of special relativity complement idealized examples with real applications and very effectively exemplify the role of a finite light travel time.Comment: 5 pages TeX, European Journal of Physics, in pres

    Pentalogy of Cantrell : the first Maltese case with successful outcome

    Get PDF
    Pentalogy of Cantrell is a rare disorder which was first described by Cantrell and his colleagues in 1958. It is comprised of congenital heart disease and midline defects. Surgical treatment is possible with internalisation of the heart, repair of associated intracardiac anomalies and repair of the thoraco-abdominal defect. In this article the authors describe the first Maltese case, with a successful outcome.peer-reviewe

    Family Effects in Youth Employment

    Get PDF
    The authors begin with the hypothesis that parental contacts play a major role in finding jobs for youth. This hypothesis is tested with a model of youth employment that includes characteristics of other family members in addition to a large set of control variables. Particular attention is paid to parental characteristics that might indicate a parent's ability to assist the youth in finding a job, including occupation, industry and education. The effects of such variables are generally not significant and do not support the initial hypothesis. However, the employment probability of a youth is significantly affected by the presence of employed siblings, indicating the presence of some intrafamily effects.

    Analysis of pressure distortion testing

    Get PDF
    The development of a distortion methodology, method D, was documented, and its application to steady state and unsteady data was demonstrated. Three methodologies based upon DIDENT, a NASA-LeRC distortion methodology based upon the parallel compressor model, were investigated by applying them to a set of steady state data. The best formulation was then applied to an independent data set. The good correlation achieved with this data set showed that method E, one of the above methodologies, is a viable concept. Unsteady data were analyzed by using the method E methodology. This analysis pointed out that the method E sensitivities are functions of pressure defect level as well as corrected speed and pattern

    Calculation of wind-driven surface currents in the North Atlantic Ocean

    Get PDF
    Calculations to simulate the wind driven near surface currents of the North Atlantic Ocean are described. The primitive equations were integrated on a finite difference grid with a horizontal resolution of 2.5 deg in longitude and latitude. The model ocean was homogeneous with a uniform depth of 100 m and with five levels in the vertical direction. A form of the rigid-lid approximation was applied. Generally, the computed surface current patterns agreed with observed currents. The development of a subsurface equatorial countercurrent was observed

    Adaptation of a general circulation model to ocean dynamics

    Get PDF
    A primitive-variable general circulation model of the ocean was formulated in which fast external gravity waves are suppressed with rigid-lid surface constraint pressires which also provide a means for simulating the effects of large-scale free-surface topography. The surface pressure method is simpler to apply than the conventional stream function models, and the resulting model can be applied to both global ocean and limited region situations. Strengths and weaknesses of the model are also presented
    corecore