680 research outputs found
Illinois Lo-Cal House
The increasing scarcity of fuels makes it imperativeto include more energy conservation features in our housing.
This circular describes the design, construction, and predicted performance of a house that uses approximately one-third of the energy needed to heat a house of the same size which is built to meet 1974 insulation standards (United States Department of Housing and Urban Development standards for houses located in areas having a heating season of between 4500 and 8000 degree-days). Because of its low-energy requirements for heating, the house has been called the "Illinois Lo-Cal House." If the Lo-Cal House is compared to the typical house of 1950, the savings are even more dramatic.
The two features which account for the exceptional
reduction are:
1) Superior insulation
2) Solar orientation
Of the reduction, about 80% or more is due to the heavy insulation. The remaining reduction is due to the location of most of the windows in the south wall, where they act as solar collectors
On the Coexistence in RuSr2GdCu2O8 of Superconductivity and Ferromagnetism
We review the reasons that make superconductivity unlikely to arise in a
ferromagnet. Then, in light of the report by Tallon and collaborators that
RuSr2GdCu2O8 becomes superconducting at approximately 35 K which is well below
the Curie temperature of 132 K, we consider whether the objections really apply
to this compound. Our considerations are supported by local spin density
calculations for this compound, which indeed indicate a ferromagnetic RuO2
layer. The Ru moment resides in t_2g orbitals but is characteristic of
itinerant magnetism (and is sensitive to choice of exchange-correlation
potential and to the atomic positions). Based on the small exchange splitting
that is induced in the Cu-O layers, the system seems capable of supporting
singlet superconductivity an FFLO-type order parameter and possibly a pi-phase
alternation between layers. If instead the pairing is triplet in the RuO2
layers, it can be distinguished by a spin-polarized supercurrent. Either type
of superconductivity seems to imply a spontaneous vortex phase if the
magnetization is rotated out of the plane.Comment: 3 revtex pages, 2 embedded figures. In press, Proc. HTS99 Conf.,
Miami, 199
Orbital moment of a single Co atom on a Pt(111) surface - a view from correlated band theory
The orbital magnetic moment of a Co adatom on a Pt(111) surface is calculated
in good agreement with experimental data making use of the LSDA+U method. It is
shown that both electron correlation induced orbital polarization and
structural relaxation play essential roles in orbital moment formation. The
microscopic origins of the orbital moment enhancement are discussed
Electronic structure and spectral properties of Am, Cm and Bk: Charge density self-consistent LDA+HIA calculations in FP-LAPW basis
We provide a straightforward and numerically efficient procedure to perform
local density approximation + Hubbard I (LDA+HIA) calculations, including
self-consistency over the charge density, within the full potential linearized
augmented plane wave (FP-LAPW) method. This implementation is all-electron,
includes spin-orbit interaction, and makes no shape approximations for the
charge density. The method is applied to calculate selected heavy actinides in
the paramagnetic phase. The electronic structure and spectral properties of Am
and Cm metals obtained are in agreement with previous dynamical mean-field
theory (LDA+DMFT) calculations and with available experimental data. We point
out that the charge density self-consistent LDA+HIA calculations predict the
charge on Bk to exceed the atomic integer value by 0.22.Comment: 8 pages, 1 figur
Orbital magnetic moment and extrinsic spin Hall effect for iron impurity in gold
We report electronic structure calculations of an iron impurity in gold host.
The spin, orbital and dipole magnetic moments were investigated using the
LDA+ correlated band theory. We show that the {\em
around-mean-field}-LDA+ reproduces the XMCD experimental data well and does
not lead to formation of a large orbital moment on the Fe atom. Furthermore,
exact diagonalization of the multi-orbital Anderson impurity model with the
full Coulomb interaction matrix and the spin-orbit coupling is performed in
order to estimate the spin Hall angle. The obtained value suggests that there is no giant extrinsic spin Hall effect due to
scattering on iron impurities in gold.Comment: 5 pages, 2 figure
Coulomb Correlations and Magnetic Anisotropy in ordered CoPt and FePt alloys
We present results of the magneto-crystalline anisotropy energy (MAE)
calculations for chemically ordered CoPt and FePt alloys taking into
account the effects of strong electronic correlations and spin-orbit coupling.
The local spin density + Hubbard U approximation (LSDA+U) is shown to provide a
consistent picture of the magnetic ground state properties when intra-atomic
Coulomb correlations are included for both 3 and 5 elements. Our results
demonstrate significant and complex contribution of correlation effects to
large MAE of these material.Comment: revised version; 4 pages, 2 figure
Multiplet effects in the electronic structure of -Pu, Am and their compounds
We propose a straightforward and efficient procedure to perform dynamical
mean-field (DMFT) calculations on the top of the static mean-field LDA+U
approximation. Starting from self-consistent LDA+U ground state we included
multiplet transitions using the Hubbard-I approximation, which yields a very
good agreement with experimental photoelectron spectra of -Pu, Am, and
their selected compounds.Comment: submitted to Europhysics Letter
Use Of A Real World Business Panel To Assist In MBA Program Outcomes Assessment And Curriculum Refinement
The world of business operates in an extremely dynamic environment. Domestic issues (competition, cultural diversity, regulation/deregulation) global issues (competition, economic, cultural/social, and political), and rapidly changing technologies all require business school curricula that are designed to be flexible and proactive as well as reactive. An ever increasingly important responsibility of schools of business is the assessment of outcomes of their programs. Outcomes may be measured on several dimensions. One such measurement is the assessment of the skills/abilities of its graduates. This work will describe the efforts of a business school to engage the local business community in that undertaking
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