1,442 research outputs found
Size Estimation of Interface Crack by Interference Effect
It is of primary importance to estimate the crack size on the interface of two solids for evaluating the integrity of jointed interfaces. In this paper, the scattering problem of elastic waves is formulated for the interface crack of layered materials in water. Greenâs function for the water/solid/solid material is constructed and utilized to represent the scattered pressure field in water caused by the crack opening displacement in the interface of two solids. Introduction of the far-field approximation for the scattered pressure field and then the high frequency approximation for the crack opening displacement leads to a simple equation which is related to the crack size, the wave velocity in water, the angles of incident wave and observation point, and the period of scattering amplitude in the frequency range. The size of interface crack is estimated by measuring the periodicity of the scattering amplitude for fixed transducerâs angles in water. Examples are shown for pulse-echo configurations
Evidence of Strong Correlation between Instanton and QCD-monopole on SU(2) Lattice
The correlation between instantons and QCD-monopoles is studied both in the
lattice gauge theory and in the continuum theory. An analytical study in the
Polyakov-like gauge, where is diagonalized, shows that the
QCD-monopole trajectory penetrates the center of each instanton, and becomes
complicated in the multi-instanton system. Using the SU(2) lattice with ,
the instanton number is measured in the singular (monopole-dominating) and
regular (photon-dominating) parts, respectively. The monopole dominance for the
topological charge is found both in the maximally abelian gauge and in the
Polyakov gauge.Comment: 4 pages, Latex, 3 figures. Talk presented by H. Suganuma at
International Symposium on 'Lattice Field Theory', July 11 - 15, 1995,
Melbourne, Australi
Confinement and Topological Charge in the Abelian Gauge of QCD
We study the relation between instantons and monopoles in the abelian gauge.
First, we investigate the monopole in the multi-instanton solution in the
continuum Yang-Mills theory using the Polyakov gauge. At a large instanton
density, the monopole trajectory becomes highly complicated, which can be
regarded as a signal of monopole condensation. Second, we study instantons and
monopoles in the SU(2) lattice gauge theory both in the maximally abelian (MA)
gauge and in the Polyakov gauge. Using the lattice, we find
monopole dominance for instantons in the confinement phase even at finite
temperatures. A linear-type correlation is found between the total
monopole-loop length and the integral of the absolute value of the topological
density (the total number of instantons and anti-instantons) in the MA gauge.
We conjecture that instantons enhance the monopole-loop length and promote
monopole condensation.Comment: 3 pages, LaTeX, Talk presented at LATTICE96(topology
Cardiac rupture after catheter ablation procedure
ArticleAnnals of Thoracic Surgery. 80(1): 326-328 (2005)journal articl
Lifshitz-Slyozov Scaling For Late-Stage Coarsening With An Order-Parameter-Dependent Mobility
The coarsening dynamics of the Cahn-Hilliard equation with order-parameter
dependent mobility, , is addressed at
zero temperature in the Lifshitz-Slyozov limit where the minority phase
occupies a vanishingly small volume fraction. Despite the absence of bulk
diffusion for , the mean domain size is found to grow as , due to subdiffusive transport of the order parameter
through the majority phase. The domain-size distribution is determined
explicitly for the physically relevant case .Comment: 4 pages, Revtex, no figure
Human Ό-calpain: Simple isolation from erythrocytes and characterization of autolysis fragments
Heterodimeric ÎŒ-calpain, consisting of the large (80 kDa) and the small (30 kDa) subunit, was isolated and purified from human erythrocytes by a highly reproducible four-step purification procedure. Obtained material is more than 95% pure and has a specific activity of 6 - 7 mU/mg. Presence of contaminating proteins could not be detected by HPLC and sequence analysis. During storage at -80 °C the enzyme remains fully activatable by CaÂČâș, although the small subunit is partially processed to a 22 kDa fragment. This novel autolysis product of the small subunit starts with the sequence (60)RILG and is further processed to the known 18 kDa fragment. Active forms and typical transient and stable autolysis products of the large subunit were identified by protein sequencing. In casein-zymograms only the activatable forms 80 kDa+30 kDa, 80 kDa+22 kDa and 80 kDa+18 kDa displayed caseinolysis
Instanton, Monopole Condensation and Confinement
The confinement mechanism in the nonperturbative QCD is studied in terms of
topological excitation as QCD-monopoles and instantons. In the 't Hooft abelian
gauge, QCD is reduced into an abelian gauge theory with monopoles, and the QCD
vacuum can be regarded as the dual superconductor with monopole condensation,
which leads to the dual Higgs mechanism. The monopole-current theory extracted
from QCD is found to have essential features of confinement. We find also close
relation between monopoles and instantons using the lattice QCD. In this
framework, the lowest glueball (1.5 1.7GeV) can be identified
as the QCD-monopole or the dual Higgs particle.Comment: Talk presented by H.Suganuma at the 5th Topical Seminar on The
Irresistible Rise of the Standard Model, San Miniato al Todesco, Italy, 21-25
April 1997 5 pages, Plain Late
Critical dynamics of phase transition driven by dichotomous Markov noise
An Ising spin system under the critical temperature driven by a dichotomous
Markov noise (magnetic field) with a finite correlation time is studied both
numerically and theoretically. The order parameter exhibits a transition
between two kinds of qualitatively different dynamics, symmetry-restoring and
symmetry-breaking motions, as the noise intensity is changed.
There exist regions called channels where the order parameter stays for a
long time slightly above its critical noise intensity. Developing a
phenomenological analysis of the dynamics, we investigate the distribution of
the passage time through the channels and the power spectrum of the order
parameter evolution. The results based on the phenomenological analysis turn
out to be in quite good agreement with those of the numerical simulation.Comment: 27 pages, 12 figure
- âŠ