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Specular suffering: (staging) the body in pain
For the abstract see the PDF fil
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Joining forces: engineering and arts students get physic(al) – problem solving strategies in the trans-school project
This paper / web article describes the practical investigations undertaken as part of the arts/engineering trans-school project.University of the Arts, London and Brunel University LTDU (APDU
The One-Loop H^2R^3 and H^2(DH)^2R Terms in the Effective Action
We consider the one-loop B^2h^3 and B^4h amplitudes in type II string theory,
where B is the NS-NS two-form and h the graviton, and expand to lowest order in
alpha'. After subtracting diagrams due to quartic terms in the effective
action, we determine the presence and structure of both an H^2R^3 and
H^2(DH)^2R term. We show that both terms are multiplied by the usual
(t_8t_8\pm{1/8}\epsilon_{10}\epsilon_{10}) factor.Comment: 20 pages, 3 figures; corrected typo
Application of inflated structures to hovercraft annual survey 1968-69: inflated structures report C1206/3
1.0 Introduction
This report surveys work carried out in the Department of Aircraft
Design at the College of Aeronautics, Cranfield, in accordance with the
terms of Ministry of Technology contract reference PD/28/045/ADM, College
of Aeronautics reference 0.1206. The period covered by this report
extends from 1st October 1968 to 1st October 1969, which constitutes
the first complete year of operation under the contract terms.
The reporting procedure agreed with Mintech is that individual research
topics shall be separately reported in the form of technical memoranda,
and that comprehensive surveys of a descriptive nature shall be submitted
at regular intervals
Magnetization Switching in Single-Domain Ferromagnets
A model for single-domain uniaxial ferromagnetic particles with high
anisotropy, the Ising model, is studied. Recent experimental observations have
been made of the probability that the magnetization has not switched. Here an
approach is described in which it is emphasized that a ferromagnetic particle
in an unfavorable field is in fact a metastable system, and the switching is
accomplished through the nucleation and subsequent growth of localized
droplets. Nucleation theory is applied to finite systems to determine the
coercivity as a function of particle size and to calculate the probability of
not switching. Both of these quantities are modified by different boundary
conditions, magnetostatic interactions, and quenched disorder.Comment: 4 pages, LaTeX, 2 figures, documentstyle{elsart} More fits and
Mathematica notebook at http://www.scri.fsu.edu/~novotny/magnetism.html To
appear in J.Mag.Mag.Mater. Conference Proceedings of 7th International
Conference on Magnetism Cairns, Australia, August, 199
The measurement of biaxial strains in coated fabric materials using the disc-replica method
A method of measuring biaxial strains in coated fabric type materials
is presented whereby the strain is deduced from the distortion of a circular
impression made on the material. The impression is placed on the material
when loaded, enabling all measurements to be made with the material in its
relaxed, unloaded, state
Target shape dependence in a simple model of receptor-mediated endocytosis and phagocytosis
Phagocytosis and receptor-mediated endocytosis are vitally important particle
uptake mechanisms in many cell types, ranging from single-cell organisms to
immune cells. In both processes, engulfment by the cell depends critically on
both particle shape and orientation. However, most previous theoretical work
has focused only on spherical particles and hence disregards the wide-ranging
particle shapes occurring in nature, such as those of bacteria. Here, by
implementing a simple model in one and two dimensions, we compare and contrast
receptor-mediated endocytosis and phagocytosis for a range of biologically
relevant shapes, including spheres, ellipsoids, capped cylinders, and
hourglasses. We find a whole range of different engulfment behaviors with some
ellipsoids engulfing faster than spheres, and that phagocytosis is able to
engulf a greater range of target shapes than other types of endocytosis.
Further, the 2D model can explain why some nonspherical particles engulf
fastest (not at all) when presented to the membrane tip-first (lying flat). Our
work reveals how some bacteria may avoid being internalized simply because of
their shape, and suggests shapes for optimal drug delivery.Comment: 18 pages, 5 figure
Mean and Extreme Radio Properties of Quasars and the Origin of Radio Emission
We investigate the evolution of both the radio-loud fraction (RLF) and (using
stacking analysis) the mean radio-loudness of quasars. We consider how these
values evolve as a function of redshift and luminosity, black hole (BH) mass
and accretion rate, and parameters related to the dominance of a wind in the
broad emission line region. We match the FIRST source catalog to samples of
luminous quasars (both spectroscopic and photometric), primarily from the Sloan
Digital Sky Survey. After accounting for catastrophic errors in BH mass
estimates at high-redshift, we find that both the RLF and the mean radio
luminosity increase for increasing BH mass and decreasing accretion rate.
Similarly both the RLF and mean radio loudness increase for quasars which are
argued to have weaker radiation line driven wind components of the broad
emission line region. In agreement with past work, we find that the RLF
increases with increasing luminosity and decreasing redshift while the mean
radio-loudness evolves in the exact opposite manner. This difference in
behavior between the mean radio-loudness and the RLF in L-z may indicate
selection effects that bias our understanding of the evolution of the RLF;
deeper surveys in the optical and radio are needed to resolve this discrepancy.
Finally, we argue that radio-loud (RL) and radio-quiet (RQ) quasars may be
parallel sequences but where only RQ quasars at one extreme of the distribution
are likely to become RL, possibly through slight differences in spin and/or
merger history.Comment: 55 pages, 28 figures, accepted to A
Visual Attention to Radar Displays
A model is described which predicts the allocation of attention to the features of a radar display. It uses the growth of uncertainty and the probability of near collision to call the eye to a feature of the display. The main source of uncertainty is forgetting following a fixation, which is modelled as a two dimensional diffusion process. The model was used to predict information overload in intercept controllers, and preliminary validation obtained by recording eye movements of intercept controllers in simulated and live (practice) interception
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