7,771 research outputs found
Failure of intuition in elementary rigid body dynamics
Suppose a projectile collides perpendicularly with a stationary rigid rod on
a smooth horizontal table. We show that, contrary to what one naturally
expects, it is not always the case that the rod acquires maximum angular
velocity when struck at an extremity. The treatment is intended for first year
university students of Physics or Engineering, and could form the basis of a
tutorial discussion of conservation laws in rigid body dynamics.Comment: Four pages; to appear in European Journal of Physic
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Making sense of higher education: students as consumers and the value of the university experience
In the global university sector competitive funding models are progressively becoming the norm, and institutions/courses are frequently now subject to the same kind of consumerist pressures typical of a highly marketised environment. In the United Kingdom, for example, students are increasingly demonstrating customer-like behaviour and are now demanding even more ‘value’ from institutions. Value, though, is a slippery concept and has proven problematic both in terms of its conceptualisation and measurement. This article explores the relationship between student value and higher education and, via study in one United Kingdom business school, suggests how this might be better understood and operationalised. Adopting a combined qualitative/quantitative approach, this article also looks to identify which of the key value drivers has most practical meaning and, coincidentally, identifies a value-related difference between home and international students
Learning Design: reflections on a snapshot of the current landscape
The mounting wealth of open and readily available information and the swift evolution of social, mobile and creative technologies warrant a re-conceptualisation of the role of educators: from providers of knowledge to designers of learning. This need is being addressed by a growing trend of research in Learning Design. Responding to this trend, the Art and Science of Learning Design workshop brought together leading voices in the field and provided a forum for discussing its key issues. It focused on three thematic axes: practices and methods, tools and resources, and theoretical frameworks. This paper reviews some definitions of Learning Design and then summarises the main contributions to the workshop. Drawing upon these, we identify three key challenges for Learning Design that suggest directions for future research
Ensuring Trust in One Time Exchanges: Solving the QoS Problem
We describe a pricing structure for the provision of IT services that ensures
trust without requiring repeated interactions between service providers and
users. It does so by offering a pricing structure that elicits truthful
reporting of quality of service (QoS) by providers while making them
profitable. This mechanism also induces truth-telling on the part of users
reserving the service
Path integrals and wavepacket evolution for damped mechanical systems
Damped mechanical systems with various forms of damping are quantized using
the path integral formalism. In particular, we obtain the path integral kernel
for the linearly damped harmonic oscillator and a particle in a uniform
gravitational field with linearly or quadratically damped motion. In each case,
we study the evolution of Gaussian wavepackets and discuss the characteristic
features that help us distinguish between different types of damping. For
quadratic damping, we show that the action and equation of motion of such a
system has a connection with the zero dimensional version of a currently
popular scalar field theory. Furthermore we demonstrate that the equation of
motion (for quadratic damping) can be identified as a geodesic equation in a
fictitious two-dimensional space.Comment: 15 pages, 6 figure
Densities with Gaussian Tails
Consider densities fi(t), for i = 1, ..., d, on the real line which have thin tails in the sense that, for each i, fi(t) ∼ γi(t)e−ψi(t), where γi behaves roughly like a constant and ψi is convex, C2, with ψ′ → ∞ and ψ″ > 0 and l/√ψ″ is self-neglecting. (The latter is an asymptotic variation condition.) Then the convolution is of the same form ft * ... *fd(t) ∼ γ(t)e − ψ(t) Formulae for γ, ψ are given in terms of the factor densities and involve the conjugate transform and infimal convolution of convexity theory. The derivations require embedding densities in exponential families and showing that the assumed form of the densities implies asymptotic normality of the exponential familie
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