12,507 research outputs found
The Structure and Freezing of fluids interacting via the Gay-Berne (n-6) potentials
We have calculated the pair correlation functions of a fluid interacting via
the Gay-Berne(n-6) pair potentials using the \PY integral equation theory and
have shown how these correlations depend on the value of n which measures the
sharpness of the repulsive core of the pair potential. These results have been
used in the density-functional theory to locate the freezing transitions of
these fluids. We have used two different versions of the theory known as the
second-order and the modified weighted density-functional theory and examined
the freezing of these fluids for and in the reduced
temperature range lying between 0.65 and 1.25 into the nematic and the smectic
A phases. For none of these cases smectic A phase was found to be stabilized
though in some range of temperature for a given it appeared as a metastable
state. We have examined the variation of freezing parameters for the
isotropic-nematic transition with temperature and . We have also compared
our results with simulation results wherever they are available. While we find
that the density-functional theory is good to study the freezing transitions in
such fluids the structural parameters found from the \PY theory need to be
improved particularly at high temperatures and lower values of .Comment: 21 Pages (in RevTex4), 6 GIF and 4 Postscript format Fig
Technology Transfer through Imports
While there is general agreement that technology differences must figure prominently in any successful account of the cross-country income variation, not much is known on the source of these technology differences. This paper examines cross-country income differences in terms of factor accumulation, domestic R&D, and foreign technological spillovers. The empirical analysis encompasses seventeen industrialized countries in four continents over three decades, at a level disaggregated enough to identify innovations in a number of key high-tech sectors. International technology transfer is found to play a crucial part in accounting for income differences. We also relate technology transfer to imports, showing that imports are often a major channel. At the same time, our analysis highlights that international technology transfer varies importantly across industries and countries.
Cyclic representations of the periodic Temperley Lieb algebra, complex Virasoro representations and stochastic processes
An -dimensional representation of the periodic
Temperley-Lieb algebra is presented. It is also a representation of
the cyclic group . We choose and define a Hamiltonian as a sum of
the generators of the algebra acting in this representation. This Hamiltonian
gives the time evolution operator of a stochastic process. In the finite-size
scaling limit, the spectrum of the Hamiltonian contains representations of the
Virasoro algebra with complex highest weights. The case is discussed in
detail. One discusses shortly the consequences of the existence of complex
Virasoro representations on the physical properties of the systems.Comment: 5 pages, 6 figure
Manual for Program PSTRESS: Peel stress computation
Described is the use of the interactive FORTRAN computer program PSTRESS, which computes a closed form solution for two bonded plates subjected to applied moments, vertical shears, and in-plane forces. The program calculates in-plane stresses in the plates, deflections of the plates, and peel and shear stresses in the adhesive. The document briefly outlines the analytical method used by PSTRESS, describes the input and output of the program, and presents a sample analysis. The results of the latter are shown to be within a few percent of results obtained using a NASTRAN finite element analysis. An appendix containing a listing of PSTRESS is included
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