We compare traditional methods of seismic event location, based on phase pick data and analysis of events one-at-a-time, with a modern method based on cross-correlation measurements and joint analysis of numerous events. In application to four different regions representing different types of seismicity and monitored with networks of different station density, we present preliminary results ind...

Cyclic cross-correlation function between image pairs of maximal length pseudo-random binary sequences is studied. It is found that the peak of the cross-correlation remains constant for every possible image pairs of the sequences of the same length. However, this unique property is not valid for all the other possible pairs.

New constructions of 3-dimensional optical orthogonal codes are presented. In each case the codes have ideal autocorrelation λa = 0, and cross correlation of λc = 1. All codes produced are demonstrated to be optimal. The constructions utilize a particular automorphism (a Singer cycle) of PG(k,q), the finite projective geometry of dimension k over the field of order q, or its affine analogue in ...

A PIV algorithm is presented for estimating time-averaged or phase-averaged velocity fields. The algorithm can be applied to situations where signal strength is not sufficient for standard cross correlation techniques, such as a low number of particle images in an interrogation spot, or poor image quality. The algorithm can also be used to increase the spatial resolution of measurements by allo...

Neher et al 2 Summary Typically, measurements that aim to predict perceived spatial impression of music signals in concert halls are performed by calculating the interaural cross-correlation coefficient (IACC) of a binaurally-recorded impulse response. Previous research, however, has shown that this can lead to results very different from those obtained if a musical input signal is used. The re...

In this paper, a coherence function technique is introduced for Tangible Acoustic Interfaces (TAI) using the Location Template Matching (LTM) approach. A simple workflow is proposed for the purpose of evaluating the performance of different TAI techniques and investigating the effect of various parameters based on experimental data. Performance analysis shows that the method of magnitude square...

Detecting a stationary, stochastic gravitational wave signal is complicated by the impossibility of observing detector noise independently of the signal. Here we describe a method of identifying this source of systematic error by varying the orientation of one of the detectors, leading to separate and independent modulations of the signal and noise contribution to the cross-correlation. The met...

Reliable estimates of vertical, inline and crossline components of apparent displacements in time-lapse seismic images are difficult to obtain for two reasons. First, features in 3-D seismic images tend to be locally planar, and components of displacement within the planes of such features are poorly resolved. Second, searching directly for peaks in 3-D cross-correlations is less robust, more c...

[1] Cross correlation of ambient seismic noise is known to result in time series from which station‐station travel‐time measurements can be made. Part of the reason that these cross‐correlation travel‐time measurements are reliable is that there exists a theoretical framework that quantifies how these travel times depend on the features of the ambient noise. However, corresponding theoretical r...

Sequences with very low out-of-phase auto-correlation and cross-correlation function are widely used for synchronization in mobile communication and multimedia systems where reliable data transmissions are required. For optimum detection, synchronization sequences usually have out-of-phase correlation values that are very low or zero. However sequences with ideal correlation function are very r...