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A new method based on the predicting of phase difference (PPM) is developed to extract phase slowness from multi-channel dispersive waves. This method is verified by synthesized multipole array waveforms and field data measured by a multipole array acoustic logging tool (MPAL). The results show that this method is fast and stable for dispersion analysis.
Let the observed sequence {yk} be generated by the multivariate ARMAX system A(z)yk = B(z)uk-1 + C(z)wk, where {wk} is the system noise with unknown covariance matrix Rw > 0, and {uk} is a sequence of mutually independent and identically distributed (iid) random vectors. Based on {yk} and {uk}, identification algorithms are proposed to simultaneously estimate the orders (p,q,r), the covariance...
In this paper, an adaptive controller for the synchronization between the generalized Lorenz hyperchaos system and the hyperchaotic Ro??ssler system is designed. The parameters of both drive and response systems are totally unknown. By utilizing the Lyapunov method and the Barbalat's lemma, global complete synchronization of the two hyperchaotic systems are obtained. Numerical simulation is carried...
The generalized Lorenz system contains a class of three-dimensional autonomous quadratic chaotic systems, including Lorenz systems, Chen systems, Lu?? systems, unified chaotic systems and some other chaotic systems. In this paper, the impulsive synchronization of two generalized Lorenz systems is studied. By exploring the structure knowledge of the system, sufficient conditions are derived. In addition,...
Formation anisotropy evaluation is very important for complex reservoir in petroleum exploration. Cross-dipole array acoustic well logging technology breaks the restriction that shear waves could not be measured in soft formations. The cross-dipole acoustic data can be used to study the formation anisotropy. This paper presents an example of cross-dipole application of multi-pole acoustic logging...
In this paper, we consider the problem of presetting the optimal batch quantities to be sold in each period for a class of non-perishable products with fixed inventory in the face of price and demand uncertainty. More specifically, we suppose that the demand in each period is an independent random variable with known distribution function, and the price is determined exogenously and fluctuates according...
To achieve a good balance between matching accuracy and computation efficiency is a key challenge for query-by-humming (QBH) system. In this paper, we propose an approach of n-gram based fast match. Our n-gram method uses a robust statistical note transcription as well as error compensation method based on the analysis of frequent transcription errors. The effectiveness of our approach has been evaluated...
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