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201.
P. N. Singh 《Pure and Applied Geophysics》1972,94(1):60-65
Summary The present paper studies the mechanical response of a piezoelectric composite transducer—with an elastic compliance partly constant and partly variable with time—acted upon by suitable thermal field besides the electrical voltage. The Laplace transform has been applied to solve the problem. 相似文献
202.
Summary A magnetic survey carried out in Sua area of the Palamau district, Bihar (India) has shown very interesting anomalies. The survey has been conducted specially to obtain the extension of the magnetite deposits which are being quarried at Sua. The interpretation of magnetic anomalies have clearly brought out the following facts: a) the magnetite is extending both sides of the quarry to a considerable distance, b) the nature of the anomaly indicates that the magnetite occurs in the form of veins. It has also been possible to find out the thickness of the veins and the depth at which they occur. 相似文献
203.
Jagdeo Singh 《Pure and Applied Geophysics》1971,85(1):269-282
Summary Thermal demagnetization of large number of samples form the Isle of Mull have been carried out. The rocks belong to the Tertiary age. The results indicate that the rocks have been magnetized in the prevalling geomagnetic field at the time of formation. Some of the rocks indicate movement during cooling. 相似文献
204.
Summary Theoretical expressions are derived for the displacement, velocity and stress in the time domain induced by an axially symmetric shearing stress applied at the inner surface of a spherical cavity in a hornogeneous, isotropic, elastic medium of infinite extent. Theoretical seismograms are computed for a step source and for three sources with exponential decay in time. A satisfactory time-dependence of the source can be obtained by combining the step source with one or more exponentially decaying sources. 相似文献
205.
V. P. Singh 《水文研究》1995,9(7):783-796
Error equations for the kinematic wave and diffusion wave approximations with lateral inflow neglected in the momentum equation are derived under simplified conditions for space-independent flows. These equations specify error as a function of time in the flow hydrograph. The kinematic wave, diffusion wave and dynamic wave solutions are parameterized through a dimensionless parameter γ which is dependent on the initial conditions. This parameter reflects the effect of initial flow depth, channel-bed slope, lateral inflow, infiltration and channel roughness when the initial condition is non-vanishing; it reflects the effect of bed slope, channel roughness and acceleration due to gravity when the initial condition is vanishing. The error equations are found to be the Riccati equation. The structure of the error equations in the case when the momentum equation neglects lateral inflow is different from that when the lateral inflow is included. 相似文献
206.
A. K. Singh 《Astrophysics and Space Science》1984,103(2):241-248
The effect of heat sinks on the free-convection flow of an incompressible viscous fluid past an impulsively started infinite vertical porous plate is considered. Finite difference method has been used to obtain the numerical solution of the governing equations. The influence of the various parameters, occurring into the problem, on the velocity field, the temperature field and on their related quantities is extensively discussed with the help of graphs and tables. 相似文献
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Shivamoggi (1983) has used the method of strained coordinates in investigating the nonlinear Rayleigh-Taylor instability problem. After incorporating the corrections pointed out by Malik and Singh (1983) he obtained a revised expression for the nonlinear cut off wavenumber which separates the region of stability from that of instability. 相似文献