45,836 research outputs found
Stability and asymptotic behavior of periodic traveling wave solutions of viscous conservation laws in several dimensions
Under natural spectral stability assumptions motivated by previous
investigations of the associated spectral stability problem, we determine sharp
estimates on the linearized solution operator about a multidimensional
planar periodic wave of a system of conservation laws with viscosity, yielding
linearized stability for all and dimensions and nonlinear stability and
-asymptotic behavior for and . The behavior can in
general be rather complicated, involving both convective (i.e., wave-like) and
diffusive effects
Beach face dynamics as affected by ground water table elevations
This report presents the results of laboratory studies which were carried out in the Coastal
and Oceanographical Engineering Laboratory to investigate the effects of ground water table
elevations on the beach profile changes over the swash zone. The experiment was conducted at
three different water table levels while the other experimental conditions were fixed to constant
values with regular waves. The water table levels included (1) normal water table level which
is the same as mean sea level, (2) a higher level and (3) a lower level than the mean sea
level. Special attention was given to the higher water level to investigate whether this level
enhances erosion of the beach face and also to methods of interpreting the experimental data.
The experiment described herein was carried out with a fairly fine sand and has demonstrated
the significance of beach water table on profile dynamics. The increased water table level
caused distinct effects in three definite zones. First, erosion occurred at the base of the beach
face and the sand eroded was carried up and deposited on the upper portion of the beach
face. Secondly, the bar trough deepened considerably and rapidly and the eroded sand was
deposited immediately landward. This depositional area changed from mildly erosional to
strongly depositional. Third, the area seaward of the bar eroded with a substantial deepening.
The lowered water table appeared to result in a much more stable beach and the resulting
effects were much less. The only noticeable trend was a limited deposition in the scour area at
the base of the beach face. (Document has 37 pages.
Polarization enhancement in ,He)n reaction: Nuclear teleportation
I show that an experimental technique used in nuclear physics may be
successfully applied to quantum teleportation (QT) of spin states of massive
matter. A new non-local physical effect the `quantum-teleportation-effect' is
discovered for the nuclear polarization measurement. Enhancement of the neutron
polarization is expected in the proposed experiment for QT that discriminates
{\it only} one of the Bell states.Comment: 3 pages, accepted for publication in J. Phys.
Peierls substitution in the energy dispersion of a hexagonal lattice
The method of the Peierls substitution in studying the magnetic subband
structure of a hexagonal lattice is re-examined. Several errors in the
formalism of a couple of recent papers are pointed out and rectified so as to
describe the effect of the magnetic field pertinently.Comment: 3 pages (two-columns), 2 EPS figures, submitted to J. Phys.: Condens.
Matte
A Study of Some Methods for Measuring CKM CP Violating Phases
We study the influence of penguin (especially, electroweak penguin) effects
on some methods of measuring the angles , , and in the
CKM unitarity triangle. We use next-to-leading order effective Hamiltonian, and
present numerical estimates based on the factorization approximation. We find
that some techniques suggested in the literature, especially for
determination, are not workable in light of the electroweak penguin effects.
Nevertheless, there are methods that would work for each angle determination.
For angle we consider mode and estimate the
penguin contamination. For angle we consider a method based on SU(3)
symmetry and carefully consider SU(3) breaking effects. We point out regions in
the parameter space where this method could be used reliably.Comment: 25 pages (Latex), 5 PS figs (uuencoded, epsf.tex
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