9,096 research outputs found
It\u27s Fun, But Is It Science? Goals and Strategies in a Problem-Based Learning Course
All students at Hampshire College must complete a science requirement in which they demonstrate their understanding of how science is done, examine the work of science in larger contexts, and communicate their ideas effectively. Human Biology: Selected Topics in Medicine is one of 18-20 freshman seminars designed to move students toward completing this requirement. Students work in cooperative groups of 4-6 people to solve actual medical cases about which they receive information progressively. Students assign themselves homework tasks to bring information back for group deliberation. The goal is for case teams to work cooperatively to develop a differential diagnosis and recommend treatment. Students write detailed individual final case reports. Changes observed in student work over six years of developing this course include: increased motivation to pursue work in depth, more effective participation on case teams, increase in critical examination of evidence, and more fully developed arguments in final written reports. As part of a larger study of eighteen introductory science courses in two institutions, several types of pre- and post-course assessments were used to evaluate how teaching approaches might have influenced students’ attitudes about science, their ability to learn science, and their understanding of how scientific knowledge is developed [1]. Preliminary results from interviews and Likert-scale measures suggest improvements in the development of some students’ views of epistemology and in the importance of cooperative group work in facilitating that development
Plethystic Vertex Operators and Boson-Fermion Correspondences
We study the algebraic properties of plethystic vertex operators, introduced
in J. Phys. A: Math. Theor. 43 405202 (2010), underlying the structure of
symmetric functions associated with certain generalized universal character
rings of subgroups of the general linear group, defined to stabilize tensors of
Young symmetry type characterized by a partition of arbitrary shape \pi. Here
we establish an extension of the well-known boson-fermion correspondence
involving Schur functions and their associated (Bernstein) vertex operators:
for each \pi, the modes generated by the plethystic vertex operators and their
suitably constructed duals, satisfy the anticommutation relations of a complex
Clifford algebra. The combinatorial manipulations underlying the results
involve exchange identities exploiting the Hopf-algebraic structure of certain
symmetric function series and their plethysms.Comment: 21 pages, LaTeX. Minor typos corrected. Added brief survey of related
work and new reference
The Hopf Algebra Structure of the Character Rings of Classical Groups
The character ring \CGL of covariant irreducible tensor representations of
the general linear group admits a Hopf algebra structure isomorphic to the Hopf
algebra \Sym$ of symmetric functions. Here we study the character rings \CO and
\CSp of the orthogonal and symplectic subgroups of the general linear group
within the same framework of symmetric functions. We show that \CO and \CSp
also admit natural Hopf algebra structures that are isomorphic to that of \CGL,
and hence to \Sym. The isomorphisms are determined explicitly, along with the
specification of standard bases for \CO and \CSp analogous to those used for
\Sym. A major structural change arising from the adoption of these bases is the
introduction of new orthogonal and symplectic Schur-Hall scalar products.
Significantly, the adjoint with respect to multiplication no longer coincides,
as it does in the \CGL case, with a Foulkes derivative or skew operation. The
adjoint and Foulkes derivative now require separate definitions, and their
properties are explored here in the orthogonal and symplectic cases. Moreover,
the Hopf algebras \CO and \CSp are not self-dual. The dual Hopf algebras \CO^*
and \CSp^* are identified. Finally, the Hopf algebra of the universal rational
character ring \CGLrat of mixed irreducible tensor representations of the
general linear group is introduced and its structure maps identified.Comment: 38 pages, uses pstricks; new version is a major update, new title,
new material on rational character
A complete distribution of redshifts for sub-millimetre galaxies in the SCUBA-2 Cosmology Legacy Survey UDS field
This is a pre-copyedited, author-produced PDF of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. Available online at https://doi.org/10.1093/mnras/stx1689. © 2017 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Sub-milllimetre galaxies (SMGs) are some of the most luminous star-forming galaxies in the Universe, however their properties remain hard to determine due to the difficulty of identifying their optical\slash near-infrared counterparts. One of the key steps to determining the nature of SMGs is measuring a redshift distribution representative of the whole population. We do this by applying statistical techniques to a sample of 761 850m sources from the SCUBA-2 Cosmology Legacy Survey observations of the UKIDSS Ultra-Deep Survey (UDS) Field. We detect excess galaxies around per cent of the 850m positions in the deep UDS catalogue, giving us the first 850m selected sample to have virtually complete optical\slash near-infrared redshift information. Under the reasonable assumption that the redshifts of the excess galaxies are representative of the SMGs themselves, we derive a median SMG redshift of , with 68 per cent of SMGs residing between $1.07Peer reviewedFinal Accepted Versio
Chord diagrams and BPHZ subtractions
The combinatorics of the BPHZ subtraction scheme for a class of ladder graphs
for the three point vertex in theory is transcribed into certain
connectivity relations for marked chord diagrams (knots with transversal
intersections). The resolution of the singular crossings using the equivalence
relations in these examples provides confirmation of a proposed fundamental
relationship between knot theory and renormalization in perturbative quantum
field theory.Comment: 12 pages, 5 Postscript figures, LaTex 2
Transportation noise pollution - Control and abatement
Control and abatement of transportation noise pollutio
TRIAD - Preliminary design of an operational earth resources survey system. 1969 summer faculty fellowship program in engineering systems design
TRIAD, preliminary design of operational earth resources survey syste
TRIAD - Preliminary design of an operational earth resources survey system Final report
Design of operational earth resources survey syste
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