In ordinary social interaction, including cooperative work, there are many structures that participants use and represent in a variety of ways, e.g., with verbal descriptions, drawings, tables, graphs, etc. For example, consider sporting events. Figure 1 shows a table from a newspaper representing the order and participants in a boat race, the Henley Regatta, while Figure 2 shows the same infor...

Introduction The heterogeneities in the crust and upper mantle structure as well as the complex source rupture process have an important influence on regional seismic wavefield, particularly for high-frequency waves. Moreover small-scale heterogeneities such as for the sedimentary basin introduce significant amplification of ground motion, which lead to long ground shaking over several minutes ...

Recent photometric and spectroscopic observations of the hybrid variable γ Pegasi [6, 5] revealed 6 frequencies of the SPB type and 8 of the β Cep type pulsations. Standard seismic models, which have been constructed with OPAL [7] and OP [12] opacities by fitting three frequencies (those of the radial fundamental and two dipole modes), do not reproduce the frequency range of observed pulsations...

spectral decomposition is a powerful tool for analysis of seismic data. fourier transform determines the frequency contents of a signal. but for analysis of non-stationary signals, 1-d transform to frequency domain is not sufficient. in early years, transforming of seismic traces into time and frequency domain was done via windowed fourier transform, called a short time fourier transform (stft)...

We study the 3-state square-lattice Potts antiferromagnet at zero temperature by a Monte Carlo simulation using the Wang-Swendsen-Kotecký cluster algorithm, on lattices up to 1024 × 1024. We confirm the critical exponents predicted by Burton and Henley based on the height representation of this model.

We discuss observations and seismic analyses for three multi-periodic δ Scuti stars in the Praesepe cluster: BU, BN and BV Cnc. For two stars (BU and BN Cnc) we re-analyse published photoelectric photometry and show that using statistical weights results in a dramatic reduction in the noise level. We detect seven frequencies in BU Cnc and eight in BN Cnc, with three of the latter being previous...

Context. There are many unknowns in the formation of subdwarf B stars. Different formation channels are considered to be possible and to lead to a variety of helium-burning subdwarfs. All seismic models to date, however, assume that a subdwarf B star is a posthelium-flash-core surrounded by a thin inert layer of hydrogen. Aims. We examine an alternative formation channel, in which the subdwarf ...

For accurate seismic hazard evaluation, both the spatial and frequency-dependent variabilities in the amplitudes of earthquake ground motions are needed. While this information is rarely fully available due to the paucity of relevant seismic data, dense arrays like the 5200-geophone array in Long Beach, California provide the opportunity to study this amplitude variability. Here we show that am...

Gravitational wave detectors aim to detect strain perturbations of space-time on the order of 10−21–10−22 at frequencies between 1 Hz and a few kHz. This space-time strain, integrated over kilometer scale interferometers, will induce movements of suspended mirrors on the order of 10−18–10−19 m. Seismic motion in this frequency band varies between 10−6 m and 10−12 m. Required seismic attenuation...

Increased monitoring of civil structures for response to earthquake motions is fundamental to reducing seismic risk. Seismic monitoring is difficult because typically only a few useful, intermediate to large earthquakes occur per decade near instrumented structures. Here, we demonstrate that the impulse response function (IRF) of a multistory building can be generated from ambient noise. Estima...