Showing papers by "Applied Science Private University published in 1972"

On a direct-iterative eigensolution technique

Abstract: Two variations of an iterative scheme are presented for the solution to algebraic eigensystems. These algorithms are used in conjunction with the method of reduced generalized co-ordinates so that n number of frequencies and mode shapes are obtained simultaneously. The bases of the scheme are the well-known results of Stodola–Vianello and Gram–Schmidt. Advantages of the present schemes are realized both in computational effort and in computer storage. Examples are presented to illustrate the convergence characteristics.

Love and Rayleigh waves in the San Fernando Valley

Abstract: By means of a recently developed finite element technique, the propagation of Love and Rayleigh waves along an approximately north-south section of the San Fernando Valley is studied. At periods of 1 sec or less, the surface amplitudes of both Love and Rayleigh waves increase considerably with distance south into the valley as the alluvium thickens. Dipping structures give rise to higher Love and Rayleigh modes which modulate the surface displacement caused by the fundamental Love and Rayleigh modes. At periods of 1 sec or less, the fundamental Love and Rayleigh modes travel almost entirely in the uppermost 9000 ft (2743 m) of the Earth9s crust. Conversion of the first higher Love mode to the fundamental mode can contribute significantly to the Love wave surface displacement. Finally, at periods of 1 sec or less, the phase velocities of the fundamental Love and Rayleigh modes depend on the displacements of these modes near the surface of the Earth. These velocities may be considerably different from the arithmetic mean of the phase velocities of the Love and Rayleigh modes at the ends of the model.

Rayleigh waves from a moving thrust fault

Abstract: The amplitude of the Rayleigh waves produced by a finite, propagating dip-slip fault of arbitrary orientation in a homogeneous, isotropic half-space is obtained The fault is assumed to initiate suddenly at depth and to spread unilaterally to the free surface with constant speed The Rayleigh-wave amplitude ahead of the fault break is shown to be considerably higher than that behind the initial epicenter There is severe amplitude modulation in the epicentral region caused by the interference of waves traveling in opposite directions The numerical results indicate that for Rayleigh waves in the period range of interest in earthquake engineering, a number of simplifications can be made in modeling an earthquake source of this type

Application of Correlation Analysis to Acoustic Emission

Abstract: : Correlation analysis techniques have been used in order to characterize acoustic emission pulses from metals. A brief description of correlation functions and the method of their determination is presented. The time varying spectra of a magnesium sample has been obtained using the present techniques, and then compared with the more common methods of measuring acoustic emission. Other uses of correlation analysis in acoustic emission studies are included. (Author)

A Decomposition Method of Determining Maximum Compatibles

Abstract: A direct method of determining the maximum compatibility sets of an incompletely specified flow table of a sequential machine is presented. Subsets of pairwise incompatibles are utilized to decompose the set of all states in a step-by-step process into the maximum compatibles in a few steps. The method is simpler and faster than previously reported tabular, algebraic, and graphical techniques.