4,125 research outputs found
Mathematic & mathematics education: searching for common ground, edited by M. Fried and T. Dreyfus, New York, Springer, 2014, 402 pp., £90, ISBN 978-94-007-7472-8
This is an Accepted Manuscript of an article published by Taylor & Francis in Research in Mathematics Education on 22nd Aug 2014, available online: http://dx.doi.org/10.1080/14794802.2014.93735
Letter to Philander Chase
A. & G. Ralston inform Philander Chase they received a draft to withdraw $200 in Chase\u27s name, but with no prior notice. They ask him to inform them in the future.https://digital.kenyon.edu/chase_letters/2065/thumbnail.jp
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Excavations and survey at Coats Hill, near Moffat, 1990-1
This report describes the results of the survey and sample excavations of small cairns,
annular structures and other remains on Coats Hill, near Moffat. The difficulties of assessing
the dates and functions of certain of the structures are discussed. The project formed
part of the archaeological studies for the North Western Ethylene Pipeline (NWEP) Project
for Shell Chemicals UK Ltd, which wholly funded the archaeological work and the publication
of this report
Hadron Helicity Violation in Exclusive Processes: Quantitative Calculations in Leading Order QCD
We study a new mechanism for hadronic helicity flip in high energy hard
exclusive reactions. The mechanism proceeds in the limit of perfect chiral
symmetry, namely without any need to flip a quark helicity. The fundamental
feature of the new mechanism is the breaking of rotational symmetry of the hard
collision by a scattering plane in processes involving independent quark
scattering. We show that in the impulse approximation there is no evidence for
of the helicity violating process as the energy or momentum transfer is
increased over the region 1 GeV^2 < Q^2 < 100 GeV^2. In the asymptotic region
Q^2> 1000 GeV^2, a saddle point approximation with doubly logarithmic accuracy
yields suppression by a fraction of power of Q^2. ``Chirally--odd" exclusive
wave functions which carry non--zero orbital angular momentum and yet are
leading order in the high energy limit, play an important role.Comment: uuencoded LaTeX file (21 pages) and PostScript figure
The Virgo Alignment Puzzle in Propagation of Radiation on Cosmological Scales
We reconsider analysis of data on the cosmic microwave background on the
largest angular scales. Temperature multipoles of any order factor naturally
into a direct product of axial quantities and cosets. Striking coincidences
exist among the axes associated with the dipole, quadrupole, and octupole CMB
moments. These axes also coincide well with two other axes independently
determined from polarizations at radio and optical frequencies propagating on
cosmological scales. The five coincident axes indicate physical correlation and
anisotropic properties of the cosmic medium not predicted by the conventional
Big Bang scenario. We consider various mechanisms, including foreground
corrections, as candidates for the observed correlations. We also consider
whether the propagation anomalies may be a signal of ``dark energy'' in the
form of a condensed background field. Perhaps {\it light propagation} will
prove to be an effective way to look for the effects of {\it dark energy}.Comment: 24 pages, 4 figures, minor changes, no change in result or
conclusions. to appear in IJMP
Excited electron-bubble states in superfluid helium-4: a time-dependent density functional approach
We present a systematic study on the excited electron-bubble states in
superfluid helium-4 using a time-dependent density functional approach. For the
evolution of the 1P bubble state, two different functionals accompanied with
two different time-development schemes are used, namely an accurate
finite-range functional for helium with an adiabatic approximation for electron
versus an efficient zero-range functional for helium with a real-time evolution
for electron. We make a detailed comparison between the quantitative results
obtained from the two methods, which allows us to employ with confidence the
optimal method for suitable problems. Based on this knowledge, we use the
finite-range functional to calculate the time-resolved absorption spectrum of
the 1P bubble, which in principle can be experimentally determined, and we use
the zero-range functional to real-time evolve the 2P bubble for several
hundreds of picoseconds, which is theoretically interesting due to the break
down of adiabaticity for this state. Our results discard the physical
realization of relaxed, metastable 2P electron-bubblesComment: 16 pages, 12 figure
THE WHEAT AND STOCKER CATTLE ANALYZER: A MICROCOMPUTER DECISION AID FOR EVALUATING WHEAT PRODUCTION AND STOCKER CATTLE GRAZING DECISIONS
The Wheat and Stocker Cattle Analyzer is a microcomputer decision aid for evaluating interrelated wheat production and stocker cattle grazing decisions under yield, weight gain, and price uncertainty. An important feature of the model is that wheat commodity program provisions are incorporated into the analysis. A wide range of alternatives including wheat production for grain only, owned stocker cattle grazing, and wheat pasture leasing can be evaluated by the program.Crop Production/Industries, Livestock Production/Industries,
Locality of quark-hadron duality and deviations from quark counting rules above resonance region
We show how deviations from the dimensional scaling laws for exclusive
processes may be related to a breakdown in the locality of quark-hadron
duality. The essential principles are illustrated in a pedagogic model of a
composite system with two spinless charged constituents, for which a dual
picture for the low-energy resonance phenomena and high-energy scaling behavior
can be established. We introduce the concept of "restricted locality" of
quark-hadron duality and show how this results in deviations from the pQCD
quark counting rules above the resonance region. In particular it can be a
possible source for oscillations about the smooth quark counting rule, as seen
e.g. in the 90-degree differential cross sections for .Comment: The way to present Eqs. (2), (4), (7) are changed while physics
contents and calculations are left intact; Additional explanations for the
forward and large-angle duality are added; Three more references are
included; Version to appear on Phys. Rev. Let
Enhancing Critical Thinking Across The Undergraduate Experience: An Exemplar From Engineering
Faculty in a large, urban school of engineering designed a longitudinal study to assess the critical thinking skills of undergraduate students as they progressed through the engineering program. The Paul-Elder critical thinking framework was used to design course assignments and develop a holistic assessment rubric. The curriculum was re-designed to include deliberate teaching of critical thinking and assessment in at least one key course for every student each year of their undergraduate curriculum. The critical thinking scores for seniors using the holistic rubric were significantly higher than their baseline critical thinking scores as freshmen (p = .004). This case-study can serve as an exemplar for other units, departments, or programs to model or replicate
The Commercial Preparation of Oxygen from Lime and Chlorine
The reaction of chlorine on a suspension of lime in the presence of suitable catalysts, such as nickel, cobalt and iron salts, has been studied. It was found that the optimum temperature is 94° C.; that the greatest unit efficiency of the catalyst, nickel nitrate, is obtained at a concentration of.02 g. per 100 c.c; that the rate of generation of oxygen is almost directly proportional to the rate of flow of the chlorine and that nickel and cobalt salts are distinctly superior to all other catalysts which were used. In addition it has been found that the catalyst is not easily poisoned, and may be used throughout a number of runs
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