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Digital generation of non-gaussian spiky excitations using spectral representation with additive phase structure / Seung H. Seong in Journal of engineering mechanics, Vol. 138 N° 10 (Octobre 2012) 

Public ISBD [article]  in Journal of engineering mechanics > Vol. 138 N° 10 (Octobre 2012) . - pp. 1236–1248. Titre : Digital generation of non-gaussian spiky excitations using spectral representation with additive phase structure Type de document : texte imprimé Auteurs : Seung H. Seong, Auteur ; Jon A. Peterka, Auteur Année de publication : 2012 Article en page(s) : pp. 1236–1248. Note générale : Mécanique appliquée Langues : Anglais (eng) Mots-clés : Digital  random  data  generation  Non-Gaussian  distribution  Spectral  method  Phase  structure Résumé : This paper presents a framework of the digital generation of non-Gaussian spiky excitations. This study is focused on the random spikiness, featuring large excursions with considerable energy and monotonic (nonstochastic) variations in a local time history. A first-order non-Gaussian stochastic time series model and its spectral representation are employed for the local spiky features. The stochastic model generates not only autocorrelation properties but also a unique shape of peaks formed with random spikes and monotonic variations between spikes. The Fourier representation of the stochastic model enables an effective control of the peaks and provides a filtering operation for the local feature generation in the frame of stationary stochastic process. Several spectral models with stochastic or ensemble-averaged amplitudes and four added phase functions have been developed. Thus, the phase is different from the uncorrelated uniform phases in a conventional spectral method. The essential feature of the method is to utilize correlations in the structured phase that are responsible for the spikiness. A four-parameter system is developed that is capable of generating spiky features while simulating specified power spectra and higher-order moments. A simple procedure for the selection of phase parameter values by a graphical method is described with illustrations of surface pressure simulation. ISSN : 0733-9399 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29EM.1943-7889.0000431 [article] Digital generation of non-gaussian spiky excitations using spectral representation with additive phase structure [texte imprimé] / Seung H. Seong, Auteur ; Jon A. Peterka, Auteur . - 2012 . - pp. 1236–1248. Mécanique appliquée Langues : Anglais (eng) in Journal of engineering mechanics > Vol. 138 N° 10 (Octobre 2012) . - pp. 1236–1248. Mots-clés : Digital  random  data  generation  Non-Gaussian  distribution  Spectral  method  Phase  structure Résumé : This paper presents a framework of the digital generation of non-Gaussian spiky excitations. This study is focused on the random spikiness, featuring large excursions with considerable energy and monotonic (nonstochastic) variations in a local time history. A first-order non-Gaussian stochastic time series model and its spectral representation are employed for the local spiky features. The stochastic model generates not only autocorrelation properties but also a unique shape of peaks formed with random spikes and monotonic variations between spikes. The Fourier representation of the stochastic model enables an effective control of the peaks and provides a filtering operation for the local feature generation in the frame of stationary stochastic process. Several spectral models with stochastic or ensemble-averaged amplitudes and four added phase functions have been developed. Thus, the phase is different from the uncorrelated uniform phases in a conventional spectral method. The essential feature of the method is to utilize correlations in the structured phase that are responsible for the spikiness. A four-parameter system is developed that is capable of generating spiky features while simulating specified power spectra and higher-order moments. A simple procedure for the selection of phase parameter values by a graphical method is described with illustrations of surface pressure simulation. ISSN : 0733-9399 En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29EM.1943-7889.0000431