The seismic reflection characterizations of a thin layer are important for reservoir geophysics. However, discussions on the reflection for a thin layer are usually restricted to precritical angle incidence. In this work, an exact analytical solution is derived to model the reflection amplitude and amplitude variation with offset (AVO) responses of a single thin bed for arbitrary incident angles. The results show that the influence of an ultra-thin bed is great for opposite-polarity reflections and is small for identical-polarity reflections. Opposite-polarity precritical reflection amplitudes first decrease in magnitude with the wavelength/thickness ratio to a local minimum, then increase to a maximum, and finally decrease gradually to zero as the layer vanishes. Opposite-polarity postcritical reflections monotonically decrease from near unity to zero, proportional to the thickness of the layer. Identicalpolarity precritical reflection amplitudes first increase in magnitude with the wavelength/thickness ratio to a local maximum, then decrease to a minimum, and finally increase to the amplitude of a single bottom reflection when the layer vanishes. Identical-polarity postcritical reflections have magnitudes near unity. The AVO responses for both opposite and identical-polarity acoustic thin beds gradually increase with angle. The influence of the Poisson's ratio of the thin bed is small for either small incidence angles or thicknesses less than 7% of the seismic wavelength, but is large for high incidence angles or thicknesses greater than 13% of the wavelength. A decrease of Poisson's ratio causes a pronounced AVO response that reaches its maximum at the quarter-wavelength tuning thickness.

We sought to explore the mediating effect of compulsory citizenship behavior in the relationship between organizational citizenship pressure and work–family conflict, and the moderating role of job autonomy in influencing the mediation. Through a 3-wave web-based survey of 312 employees in China, we found that organizational citizenship pressure was positively related to compulsory citizenship behavior, the positive impact of citizenship pressure on work–family conflict was mediated by compulsory citizenship behavior, and job autonomy mitigated the above mediation effect. Our findings provide insight into the mechanisms that underpin the effect of organizational citizenship pressure on work–family conflict.

The scattering of elastic waves by an elastic or viscoelastic cylinder is investigated numerically. The analytical solutions of the scattered and internal fields excited by a normally incident plane P wave or SV  wave are derived in a concise form. Solutions for cylindrical P‐wave incidence and for some special cases of the cylinder medium and the matrix medium are also evaluated explicitly. Numerical results for directivity patterns, scattering cross‐sections and synthetic seismograms are given for both non‐absorbing and absorbing cylinders. Results show that the directivity patterns that undergo a mode conversion (the P–SV  scattering and the SV –P scattering) are invariant as ka increases, k being the wavenumber and a the cylinder radius, the P–P scattering and the SV –SV  scattering concentrate to the forward direction and all scattering waves (P–P, SV –SV  and P–SV  or SV –P) grow into more complicated structures. The interference of diffracted and transmitted waves causes the maxima and minima in the curves of scattering cross‐sections, and the small high‐frequency peaks that appear in a low‐velocity non‐absorbing cylinder correspond to the resonance scattering. The total scattered field is mainly the superposition of the geometrically transmitted waves (P1 P2 P1 , P1 P2 S1 and P1 S2 S1 for P‐wave incidence and S1 S2 S1 , S1 S2 P1 and S1 P2 P1 for SV‐wave incidence) that go through the cylinder and the diffracted waves (P1 P^1 P1 and P1 P^1 S1 for P‐wave incidence and S1 Ŝ1 S1 and S1 P^1 P1 for SV‐wave incidence) that propagate on the matrix side of the cylinder interface. The arrival times and the waveforms of these different wave pulses depend on the positions of the observation points and the elastic parameters of the medium.

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The anisotropy of a periodically layered isotropic medium is numerically modeled in order to study the effect of the scale of heterogeneity on seismic observations. An important motivation is to delineate the wavelength ranges over which a pulse propagating obliquely through the structure will be described by either ray (short wavelength) or effective medium (long wavelength) theory. The same band-limited pulse is propagated obliquely at a variety of incidence angles through a compositionally uniform layered structure as a function of the layer thicknesses. The resulting seismograms display similar behavior to that encountered for normal incidence including the effects of stop-and pass-bands. Velocities determined from time picks on these seismograms show a large difference in velocities between the long and short wavelength limits as has been previously demonstrated for normal incidence propagation. The bulk of the transition between these two limits is independent of incidence angle and occurs when the ratio between the wavelength and the layering thickness is near a value of 10. Two more geologically reasonable models show that these effects are diminished with smaller contrasts between the layers.