Angular Spectra for non-Gaussian Isotropic Fields

Cosmic Microwave Background (CMB) Anisotropies is a subject of intensive research in several fields of sciences. In this paper we start a systematic development of basic notions and theory in statistics according to the application for CMB. The main result of this paper is the necessary and sufficient condition for isotropy of a non-Gaussian field in terms of spectra. Clear formulae for bi-, tri- and polyspectra and bi-, tri-, and higher order covariances are also given. Keywords: Bispectrum, Trispectrum, Angular poly-Spectra, Cosmic microwave background radiation; Gaussianity; spherical random fieldsComment: 53 page

La cathédrale gréco-catholique de la Sainte Trinité à Balázsfalva: influences orientales et occidentales | The Greek-Catholic cathedral of the Holy Trinity in Balázsfalva (Blaj): Oriental and occidental influences

Après avoir brièvement rappelé les circonstances historiques de sa construction, Szilveszter Terdik fait l’inventaire de la décoration religieuse de la cathédrale. Il montre notamment l’effort de fidélité aux grands principes de l’art byzantin tout en décrivant certaines inflexions dévoilant l’intention de rapprochement avec Rome ; double tendance renforcée par l’implication de deux artistes aux parcours différents. | After briefly summarizing the historical circumstances of its construction, Szilveszter Terdik compiles a kind of inventory of the religious decoration of the cathedral. He demonstrates the effort to maintain loyalty to the main principal of the byzantine art, while describing certain inflexions that show the intention to get closer to Rome. Moreover, these two tendencies were sustained by two different artists

IDENTIFICATION OF NONLINEAR VEHICLE DYNAMICS WITH UNOBSERVABLE INPUT

The realization problem and identification procedure of simple nonlinear vehicle dynamics are studied using the estimated spectrum and bispectrum of the output (vertical acceleration) process when the input excitation is (in real time) unobservable