the impact of meteorological and hydrological drought on groundwater resources in coastal deserts in the south of iran was investigated during 1991-2011, using standardized precipitation index (spi), standardized runoff index (sri), and groundwater resources index (gri). the results indicated that wet and drought spells governed the area in the first and second decades, respectively, which was ...

In this paper, we obtain the cross-correlation spectrum of generalized bent Boolean functions in a subclass of MaioranaMcFarland class (GMMF). An affine transformation which preserve the cross-correlation spectrum of two generalized Boolean functions, in absolute value is also presented. A construction of generalized bent Boolean functions in (n+ 2) variables from four generalized Boolean funct...

In this paper we examine two couplings that produce time-shifted synchronization in a pair of chaotic oscillators. The couplings do not utilize an explicit timedelay term. We characterize the observed synchronization by determining the dependence of the time shift and cross correlation between the drive and response oscillators on a tunable parameter. Our observations agree well with estimates ...

We describe a new approach to constrain the amplitude of matter perturbations in the Universe using galaxy clusters. We combine the galaxy cluster X-ray luminosity function of the REFLEX survey with the mass– luminosity relationship obtained via gravitational lensing from a sample of galaxy clusters identified in Sloan Digital Sky Survey commissioning data and confirmed through cross-correlatio...

In this paper we present an algorithm for fast calculation of the normalized cross correlation NCC and its applica tion to the problem of template matching Given a template t whose position is to be determined in an image f the basic idea of the algorithm is to represent the template for which the normalized cross correlation is calculated as a sum of rectangular basis functions Then the correl...

where x̄ is the complex conjugate of x This paper uses the machinery of almost periodic functions to prove that even without uniform convergence the connection between a pair of almost periodic functions and the constants of the associated Fourier series exists for both the convolution and cross-correlation. The general results for two almost periodic functions are narrowed and applied to Ramanu...

Consider two multi-dimensional digital signals, each with Ns samples. For some number of lags Nl Ns, the cost of computing a single cross-correlation of these two signals is proportional to Ns ×Nl. By exploiting several properties of Gaussian windows, we can compute Ns local cross-correlations, again with computational cost proportional to Ns×Nl. Here, local means the cross-correlation of signa...

Inter-aural time differences (ITDs) constitute an important localization cue for azimuth estimation, particularly below 1.5 kHz. As a first approximation, it is commonly assumed that ITDs do not depend on frequency. Nevertheless, Kuhn (JASA, 1977) shows theoretically and experimentally that due to diffraction effects around the head, ITDs depend on frequency. Low frequency ITDs should thus theo...

A typical imaging condition for seismic reflection data involves source and receiver wavefield matching, e.g. by cross-correlation, at every image location. This statement is true no matter how the two wavefields are reconstructed, for example by one-way wavefield extrapolation, or two-way reverse-time extrapolation, or Kirchhoff integral methods. This statement is also true when the source and...

Computational sound localisation using binaural microphones requires accurate Interaural Time Difference (ITD) estimation in order to infer an angle of incidence. The Phase Transform weighting function, used in generalized cross correlation calculations for microphone arrays is investigated here for application to ITD estimation in binaural head recordings. Empirical measurements using the meth...