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āVoyagerā: An educational card game
āVoyagerā is an educational card game involving scientific satellites, developed for use in schools with children aged 9 to 13 years. The idea of the game is to improve pupilsā knowledge about the large number of scientific satellites there are in space in a fun way, while also practising numeracy skills. Several copies of the game were produced using funding obtained from the Particle Physics and Astronomy Research Council (PPARC) as a Public Understanding of Science (PUS) award. These initial ātrialā versions of the game were taken to three different schools where feedback obtained from both pupils and staff was used to produce a final copy of the game that can be distributed to other schools along with a set of companion notes to form the basis of a science lesson. This article reports the findings of the school trials and indicates possible future developments of other scientific card games that could be beneficial to the classroom.http://www.iop.org/EJ/abstract/0031-9120/38/1/30
Kolmogorov-Burgers Model for Star Forming Turbulence
The process of star formation in interstellar molecular clouds is believed to
be controlled by driven supersonic magnetohydrodynamic turbulence. We suggest
that in the inertial range such turbulence obeys the Kolmogorov law, while in
the dissipative range it behaves as Burgers turbulence developing shock
singularities. On the base of the She-Leveque analytical model we then predict
the velocity power spectrum in the inertial range to be E_k ~ k^{-1.74}. This
result reproduces the observational Larson law, ~ l^{0.74...0.76},
[Larson, MNRAS 194 (1981) 809] and agrees well with recent numerical findings
by Padoan and Nordlund [astro-ph/0011465]. The application of the model to more
general dissipative structures, with higher fractal dimensionality, leads to
better agreement with recent observational results.Comment: revised, new material added, 8 page
Nonlinear adaptive control using non-parametric Gaussian Process prior models
Nonparametric Gaussian Process prior models, taken from Bayesian statistics methodology are used to implement a nonlinear adaptive control law. The expected value of a quadratic cost function is minimised, without ignoring the variance of the model predictions. This leads to implicit regularisation of the control signal (caution), and excitation of the system. The controller has dual features, since it is both tracking a reference signal and learning a model of the system from observed responses. The general method and its main features are illustrated on a simulation example
Simulation of MeV electron energy deposition in CdS quantum dots absorbed in silicate glass for radiation dosimetry
Copyright @ 2010 IOP Publishing Ltd. The conference proceedings contain the written papers of the contributions presented at Quantum Dot 2010 (QD2010). The conference was held in Nottingham, UK, on 26thā30th April, 2010.We are currently developing 2D dosimeters with optical readout based on CdS or CdS/CdSe core-shell quantum-dots using commercially available materials. In order to understand the limitations on the measurement of a 2D radiation profile the 3D deposited energy profile of MeV energy electrons in CdS quantum-dot-doped silica glass have been studied by Monte Carlo simulation using the CASINO and PENELOPE codes. Profiles for silica glass and CdS quantum-dot-doped silica glass were then compared
Teaching Students to Fish: Creating a Sustainable Student Peer Research Program
A Peer Research Mentor (PRM) program was developed at Musselman Library, Gettysburg College to augment traditional reference services and expand library outreach. Goals included enhancing these studentsā information literacy skills helping them become better researchers, as well as sharing that knowledge with peers. This poster will highlight the initial and on-going training, their involvement at the reference desk, and outreach projects to date
Rubber-coated bellows improves vibration damping in vacuum lines
Compact-vibration damping systems, consisting of rubber-coated metal bellows with a sliding O-ring connector, are used in vacuum lines. The device presents a metallic surface to the vacuum system and combines flexibility with the necessary stiffness. It protects against physical damage, reduces fatigue failure, and provides easy mating of nonparallel lines
Black hole singularities: a numerical approach
The singularity structure of charged spherical collapse is studied by
considering the evolution of the gravity-scalar field system. A detailed
examination of the geometry at late times strongly suggests the validity of the
mass-inflation scenario~\cite{PI:90}. Although the area of the two-spheres
remains finite at the Cauchy horizon, its generators are eventually focused to
zero radius. Thus the null, mass-inflation singularity {\em generally}\/
precedes a crushing singularity deep inside the black hole core. This
central singularity is spacelike.Comment: 4 pages Phys. Rev. style including five figures, provided as
compressed postscript files. To appear in Physical Review Letter
Fluorescence Analysis for Multi-Site Aluminum Binding to Natural Organic Matter
Natural organic matter (NOM) samples isolated from different water sources in Norway were compared using their fluorescence properties. Fluorescence surfaces were observed at pH 4.36 and deconvoluted using SIMPLISMA (Windig and Guilment 1991). There were a total of seven different fluorophores observed for these samples and each sampling site had between four and six ofthe fluorescent components. These components were observed to bind Al during titrations at the same pH. Multiresponse titration curves were fit using the method of Smith and Kramer (1998) and most of the binding strengths are similar to values for Suwannee River fulvic acid (1ogKā between 4.8 and 5.5), but there are strong sites (IogKā = 7) and weak sites (1ogKā between 3 and 4) also observed. Results depended on the isolation method used; reverse osmosis and low pressure evaporation yielded different values but with no consistent trends
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