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Open Science Happens Somewhere: Exploring the use of Science OER in Schools
This paper concerns a pilot exploring the use of openly licensed content in secondary schools. Specifically it looks at the use of the Open University’s (OU) OpenScienceLab (OSL) in two remote rural schools in the West Highlands of Scotland. OSL is a series of online experiments openly licensed for anyone to use, they are about learning through experimentation, and are part of a wider OU interest in how to support and develop inquiry based learning at a distance (Scanlon 2012). This area is of particular relevance to Scottish schools, as the underlying pedagogy of Curriculum for Excellence (CfE) promotes interdisciplinary thinking and learning through inquiry (Macintyre 2014).
The idea of the pilot was to work on how “open content” might be used in schools to understand what openness might mean in and for educational practice. While our initial intention was simply to run these in schools after the first workshops it became apparent while the technical and licences were open and it was relatively clear how to do the experiments, people were uncertain how to use them in their educational practice. Emphasising the need to attend to Educational Practice as well as Openness in OEP.
The pilot took a participatory design approach (Sanders and Westerlund 2011; Mor et.al 2012), to developing and support practices around the use of Open Educational Resources (OER) in classroom. Through a series of workshops and schools visits we looked to solve these problems from the classroom out, using the teachers experience to develop learning journeys that worked for teachers and pupils. With teachers we created a learning journey using the OU’s free platform OpenLearnWorks to wrap the experiments in a mixture of existing and newly developed OER.
Two journeys were created, these will be run in two locations with with two sets of teachers in December 2014. The paper will report on the outcomes for pupils and teachers of this final stage. In doing so it will reflect on the participatory design process, highlighting the practices developed to support the use of open content, drawing out broader conclusions might support the use open materials in the classroom
On the Kantorovich–Rubinstein theorem
AbstractThe Kantorovich–Rubinstein theorem provides a formula for the Wasserstein metric W1 on the space of regular probability Borel measures on a compact metric space. Dudley and de Acosta generalized the theorem to measures on separable metric spaces. Kellerer, using his own work on Monge–Kantorovich duality, obtained a rapid proof for Radon measures on an arbitrary metric space. The object of the present expository article is to give an account of Kellerer’s generalization of the Kantorovich–Rubinstein theorem, together with related matters. It transpires that a more elementary version of Monge–Kantorovich duality than that used by Kellerer suffices for present purposes. The fundamental relations that provide two characterizations of the Wasserstein metric are obtained directly, without the need for prior demonstration of density or duality theorems. The latter are proved, however, and used in the characterization of optimal measures and functions for the Kantorovich–Rubinstein linear programme. A formula of Dobrushin is proved
Testing the validity of the effective rate constant approximation for surface reaction with transport
AbstractWhen one incorporates transport effects into a surface-volume reaction, an integrodifferential equation for the bound state concentration occurs. Such a form is inconvenient for data analysis. An effective rate constant approximation for the solution is correct to O(Da2) as the Damköhler number Da → 0. A numerical simulation of the integrodifferential equation is performed which shows that the effective rate constant approximation is useful even outside this regime
Effect of Interband Transitions on the c axis Penetration Depth of Layered Superconductors
The electromagnetic response of a system with two planes per unit cell
involves, in addition to the usual intraband contribution, an added interband
term. These transitions affect the temperature dependence and the magnitude of
the zero temperature c-axis penetration depth. When the interplane hopping is
sufficiently small, the interband transitions dominate the low temperature
behaviour of the penetration depth which then does not reflect the linear
temperature dependence of the intraband term and in comparison becomes quite
flat even for a d-wave gap. It is in this regime that the pseudogap was found
in our previous normal state calculations of the c-axis conductivity, and the
effects are connected.Comment: 8 pages, 5 figure
Sedimentology and kinematics of a large, retrogressive growth-fault system in Upper Carboniferous deltaic sediments, western Ireland
Growth faulting is a common feature of many deltaic environments and is vital in determining local sediment dispersal and accumulation, and hence in controlling the resultant sedimentary facies distribution and architecture. Growth faults occur on a range of scales, from a few centimetres to hundreds of metres, with the largest growth faults frequently being under-represented in outcrops that are often smaller than the scale of feature under investigation. This paper presents data from the exceptionally large outcrops of the Cliffs of Moher, western Ireland, where a growth-fault complex affects strata up to 60 m in thickness and extends laterally for 3 km. Study of this Namurian (Upper Carboniferous) growth-fault system enables the relationship between growth faulting and sedimentation to be detailed and permits reconstruction of the kinematic history of faulting. Growth faulting was initiated with the onset of sandstone deposition on a succession of silty mudstones that overlie a thin, marine shale. The decollement horizon developed at the top of the marine shale contact for the first nine faults, by which time aggradation in the hangingwall exceeded 60 m in thickness. After this time, failure planes developed at higher stratigraphic levels and were associated with smaller scale faults. The fault complex shows a dominantly landward retrogressive movement, in which only one fault was largely active at any one time. There is no evidence of compressional features at the base of the growth faults, thus suggesting open-ended slides, and the faults display both disintegrative and non-disintegrative structure. Thin-bedded, distal mouth bar facies dominate the hangingwall stratigraphy and, in the final stages of growth-fault movement, erosion of the crests of rollover structures resulted in the highest strata being restricted to the proximity of the fault. These upper erosion surfaces on the fault scarp developed erosive chutes that were cut parallel to flow and are downlapped by the distal hangingwall strata of younger growth faults
Chiral Symmetry restoration in the massive Thirring model at finite T and : Dimensional reduction and the Coulomb gas
We show that in certain limits the (1+1)-dimensional massive Thirring model
at finite temperature is equivalent to a one-dimensional Coulomb gas of
charged particles at the same . This equivalence is then used to explore the
phase structure of the massive Thirring model. For strong coupling and
(the fermion mass) the system is shown to behave as a free gas of "molecules"
(charge pairs in the Coulomb gas terminology) made of pairs of chiral
condensates. This binding of chiral condensates is responsible for the
restoration of chiral symmetry as . In addition, when a fermion
chemical potential is included, the analogy with a Coulomb gas
still holds with playing the role of a purely imaginary external electric
field. For small and we find a typical massive Fermi gas behaviour
for the fermion density, whereas for large it shows chiral restoration by
means of a vanishing effective fermion mass. Some similarities with the chiral
properties of low-energy QCD at finite and baryon chemical potential are
discussed.Comment: 28 pages, 6 figures, better resolution figures are available upon
reques
Linear response of vibrated granular systems to sudden changes in the vibration intensity
The short-term memory effects recently observed in vibration-induced
compaction of granular materials are studied. It is shown that they can be
explained by means of quite plausible hypothesis about the mesoscopic
description of the evolution of the system. The existence of a critical time
separating regimes of ``anomalous'' and ``normal'' responses is predicted. A
simple model fitting into the general framework is analyzed in the detail. The
relationship between this work and previous studies is discussed.Comment: 10 pages, 6 figures; fixed errata, updtated reference
Condensate fraction and critical temperature of a trapped interacting Bose gas
By using a mean field approach, based on the Popov approximation, we
calculate the temperature dependence of the condensate fraction of an
interacting Bose gas confined in an anisotropic harmonic trap. For systems
interacting with repulsive forces we find a significant decrease of the
condensate fraction and of the critical temperature with respect to the
predictions of the non-interacting model. These effects go in the opposite
direction compared to the case of a homogeneous gas. An analytic result for the
shift of the critical temperature holding to first order in the scattering
length is also derived.Comment: 8 pages, REVTEX, 2 figures, also available at
http://anubis.science.unitn.it/~oss/bec/BEC.htm
Slow dynamics for the dilute Ising model in the phase coexistence region
In this paper we consider the Glauber dynamics for a disordered ferromagnetic
Ising model, in the region of phase coexistence. It was conjectured several
decades ago that the spin autocorrelation decays as a negative power of time
[Huse and Fisher, Phys. Rev. B, 1987]. We confirm this behavior by establishing
a corresponding lower bound in any dimensions , together with an
upper bound when . Our approach is deeply connected to the Wulff
construction for the dilute Ising model. We consider initial phase profiles
with a reduced surface tension on their boundary and prove that, under mild
conditions, those profiles are separated from the (equilibrium) pure plus phase
by an energy barrier.Comment: 44 pages, 6 figure
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