Previous authors have tried to image seismic reflectivity by crosscorrelating passive seismic data, and treating the resultant correlograms as active source seismograms. We provide a mathematical framework for working with passive seismic correlograms that is both appropriate for V (x , y, z) media, and arbitrary source location. Under this framework, correlograms can be migrated with an imagin...

An overview of Gaussian beam imaging is given for converted and surface reflected seismic waves. The earthquake seismology community now regularly uses seismic waves from distant sources to illuminate structures beneath seismic arrays in so-called passive imaging experiments. Similarly, reservoir structures can be imaged with seismic waves incident from below using sources in boreholes. Gaussia...

A mathematical model to compute the overall vibrational response of connected multistructure mechanical systems is presented. Using the proposed model, structural vibration control strategies for seismic protection of multibuilding systems can be efficiently designed. Particular attention is paid to the design of control configurations that combine passive interbuilding dampers with local feedb...

This study firstly proposes some representative simple methods to obtain the suboptimal passive damping and stiffness parameters from the optimal control gain matrix since it is not possible to add the exact optimal damping and stiffness parameters to the structure in practice. It is shown numerically that modifying the structural damping and the stiffness in the proposed suboptimal ways may su...

The correlation of ambient vibrations of the Earth yields the impulse response between two passive sensors as if one was a source. This provides the opportunity to image the Earth beneath regional seismic arrays. In this paper, we present imaging of the lithosphere in Europe based on surface Rayleigh waves extracted from continuous record of the seismic noise. We also recall a brief history of ...

Due to limitations on the use of passive base isolation systems which show poor performance in near field seismic excitations or active systems which require high external power, as stand alone control devices for a range of seismic excitations, a hybrid control system that mitigates the limitations of either passive or active control systems is preferred. The present study examines the use of ...

Seismic interferometry recovers the Green's function between two receivers by cross-correlating the field measured from sources that surround the receivers. In the seismic literature, it has been widely reported that this processing can produce artifacts in the Green's function estimate called "spurious multiples" or the "virtual refracted wave." The spurious multiples are attributed to the hea...

Temporal changes of seismic properties, such as velocity, attenuation, anisotropy, and scattering properties, have been inferred by active methods for decades and more recently by passive methods. In particular, passive methods are capable of monitoring seismic properties because they do not require earthquakes but rely on continuously excited signals in the ocean, for example, a collection of ...

In this paper, a control strategy to reduce the vibrational response of adjacent buildings under seismic excitation is presented. The proposed strategy combines passive linking elements with an active decentralized H∞ control system. The overall active-passive control system admits decentralized design and operation, and achieves an excellent vibrational reduction when the active control system...