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Numerical treatment of seismic accelerograms and of inelastic seismic structural responses using harmonic wavelets
The harmonic wavelet transform is employed to analyze various kinds of nonstationary signals common in aseismic design. The effectiveness of the harmonic wavelets for capturing the temporal evolution of the frequency content of strong ground motions is demonstrated. In this regard, a detailed study of important earthquake accelerograms is undertaken and smooth joint time-frequency spectra are provided for two near-field and two far-field records; inherent in this analysis is the concept of the mean instantaneous frequency. Furthermore, as a paradigm of usefulness for aseismic structural purposes, a similar analysis is conducted for the response of a 20-story steel frame benchmark building considering one of the four accelerograms scaled by appropriate factors as the excitation to simulate undamaged and severely damaged conditions for the structure. The resulting joint time-frequency representation of the response time histories captures the influence of nonlinearity on the variation of the effective natural frequencies of a structural system during the evolution of a seismic event. In this context, the potential of the harmonic wavelet transform as a detection tool for global structural damage is explored in conjunction with the concept of monitoring the mean instantaneous frequency of records of critical structural responses
Self-consistent account for phonon induced corrections to quadrupole moments of odd nuclei. Pole and non-pole diagrams
Recent results of the description of quadrupole moments of odd semi-magic
nuclei are briefly reviewed. They are based on the self-consistent theory of
finite Fermi systems with account for the phonon-particle coupling (PC)
effects. The self-consistent model for describing the PC effects was developed
previously for magnetic moments. Account for the non-pole diagrams is an
important ingredient of this model. In addition to previously reported results
for the odd In and Sb isotopes, which are the proton-odd neighbors of even tin
nuclei, we present new results for odd Bi isotopes, the odd neighbors of even
lead isotopes. In general, account for the PC corrections makes the agreement
with the experimental data significantly better.Comment: 8 pages, 4 figures. Presented at ICNFP1
On a connection between the switching separability of a graph and that of its subgraphs
A graph of order is called {switching separable} if its modulo-2 sum
with some complete bipartite graph on the same set of vertices is divided into
two mutually independent subgraphs, each having at least two vertices. We prove
the following: if removing any one or two vertices of a graph always results in
a switching separable subgraph, then the graph itself is switching separable.
On the other hand, for every odd order greater than 4, there is a graph that is
not switching separable, but removing any vertex always results in a switching
separable subgraph. We show a connection with similar facts on the separability
of Boolean functions and reducibility of -ary quasigroups. Keywords:
two-graph, reducibility, separability, graph switching, Seidel switching, graph
connectivity, -ary quasigroupComment: english: 9 pages; russian: 9 page
Ultracold neutral plasma expansion in two dimensions
We extend an isothermal thermal model of ultracold neutral plasma expansion
to systems without spherical symmetry, and use this model to interpret new
fluorescence measurements on these plasmas. By assuming a self-similar
expansion, it is possible to solve the fluid equations analytically and to
include velocity effects to predict the fluorescence signals. In spite of the
simplicity of this approach, the model reproduces the major features of the
experimental data
A connection between the Camassa-Holm equations and turbulent flows in channels and pipes
In this paper we discuss recent progress in using the Camassa-Holm equations
to model turbulent flows. The Camassa-Holm equations, given their special
geometric and physical properties, appear particularly well suited for studying
turbulent flows. We identify the steady solution of the Camassa-Holm equation
with the mean flow of the Reynolds equation and compare the results with
empirical data for turbulent flows in channels and pipes. The data suggests
that the constant version of the Camassa-Holm equations, derived under
the assumptions that the fluctuation statistics are isotropic and homogeneous,
holds to order distance from the boundaries. Near a boundary, these
assumptions are no longer valid and the length scale is seen to depend
on the distance to the nearest wall. Thus, a turbulent flow is divided into two
regions: the constant region away from boundaries, and the near wall
region. In the near wall region, Reynolds number scaling conditions imply that
decreases as Reynolds number increases. Away from boundaries, these
scaling conditions imply is independent of Reynolds number. Given the
agreement with empirical and numerical data, our current work indicates that
the Camassa-Holm equations provide a promising theoretical framework from which
to understand some turbulent flows.Comment: tex file, 29 pages, 4 figures, Physics of Fluids (in press
Microbial Population and Fermentation Characteristic in Response to Sapindus Rarak Mineral Block Supplementation
This experiment was conducted to evaluate the effect of supplementation with lerak extract combined with mineral block on protozoal and bacterial population, and fermentation characteristic in vitro. The experimental design was completely randomized block design with 3 treatments and 4 replications. Control diet was a substrate that consisted of concentrate, forage and feed block with ratio 50 : 48 : 2, respectively. The treatments as a substrate were: control diet (C), C + 0.09% lerak extract, and C + 0.18% lerak extract from the total ration. Variables observed were protozoal and bacterial population, dry matter and organic matter degradability, N-NH3 and total volatile fatty acid (VFA) concentration. Data were analyzed using analysis of variance (ANOVA). The result showed that there were no significant effect (P>0.05) for all parameter measured with lerak extract supplementation up to 0.18% in the presence of mineral block. However, supplementation of lerak extract 0.18% only slightly reduced protozoal numbers but tended to increase bacterial numbers. Dry matter and organic matter degradability and concentration of N-NH3 were similar among treatments. Volatile fatty acids profile changed which propionate tended to increase and acetate tended to decrease and ratio of acetate to propionate tended to decrease. In conclusion, addition of lerak extract up to 0.18% from total ration in the presence of mineral block was not yet effective to depress protozoal population, but could modify fermentation characteristic in vitro
General dilatonic gravity with an asymptotically free gravitational coupling constant near two dimensions
We study a renormalizable, general theory of dilatonic gravity (with a
kinetic-like term for the dilaton) interacting with scalar matter near two
dimensions. The one-loop effective action and the beta functions for this
general theory are written down. It is proven that the theory possesses a
non-trivial ultraviolet fixed point which yields an asymptotically free
gravitational coupling constant (at ) in this regime.
Moreover, at the fixed point the theory can be cast under the form of a
string-inspired model with free scalar matter. The renormalization of the
Jackiw-Teitelboim model and of lineal gravity in dimensions is
also discussed. We show that these two theories are distinguished at the
quantum level. Finally, fermion-dilatonic gravity near two dimensions is
considered.Comment: LaTeX, 13 pages, no figure
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