Upper mantle seismic anisotropy beneath a convergent boundary:SKS waveform modeling in central Tibet

This study used SKS waveforms from the International Deep Profiling of Tibet and the Himalayas(INDEPTH) III dataset and a new 2D method for modeling seismic waves in anisotropic media to construct an image of anisotropic structures beneath central Tibet.A preferred model revealed three-segment anisotropic structures in the upper mantle beneath the study region.Waveform modeling demonstrated that the anisotropy was mainly generated by the lithosphere but not the asthenosphere,and that an anisotropic model with a flatter axis of symmetry provides a more consistent interpretation of the observations than models having steeply dipping symmetry axes.A relatively low velocity zone may underlie or intermingle with the anisotropic structures in the northern portion of the region.Synthetic tests also indicate that variations in the elastic constants and depth extent of the anisotropy assumed by the calculations do not affect the general conclusions,although trade-offs exist among certain model parameters.The modeling results suggest that the complex seismic structures in central Tibet were associated with underthrusting of the Indian lithosphere beneath the Asian lithosphere;the inferred flat symmetry axis of the anisotropy was likely generated during this collision process.If this were not the case,the inherited anisotropy would exhibit a steeply dipping axis of symmetry,parallel to the direction of underthrusting.

The effect of transcorneal electrical stimulation in visual acuity: Retinitis pigmentosa

Transcorneal Electrical Stimulation (TES) was applied to a group of volunteer patients suffering from Retinitis Pigmentosa (RP), in order to investigate the effect of TES in Visual Acuity (VA). 28 partial blind patients with diagnosis of classic RP, Usher syndrome I and/or II were stimulated transcornealy, during a period of 52 weeks using a non conventional waveform, only in the lowest visually capable eye. The proposed waveform has been modeled from the natural response of human retina and delivered by means of an adaptive generator designed and built for tissue stimulation. Statistical results show the improvement of average VA or at least the contention of the disease natural progress. Categorized analysis of results indicates the same effect that if the age of patients, time since diagnosis and genetic disorder variation (classic RP, Usher syndrome I and/or II) are considered, in this case clinical and electrophysiological follow-up parameters were statistically analyzed in order to know the effect of TES. General results yield an improvement of 48.15% in the average of VA for stimulated eyes against an average degreasing of -8.06% in the same scale, with respect to their basal condition before the start of the experiment.

Analysis on rupture feature of a great complicated earthquake in Kamchatka

The M S=7.3 earthquake of June, 8 1993, off the eastern coast of Kamchatka was very complicated in the rupture history. The rupture feature of this event was discussed by the broadband waveform modelling method as well as the combining analysis on the subevent stack and the quasi time difference. The results suggest that the rupture propagation of the event was in a strong unidirection and its main rupture processes can be expressed as: rupture nucleation→NEE→near east by north→near east by south→stop, from deep to shallow.

APPLICATION OF FRF ESTIMATOR BASED ON ERRORS-IN-VARIABLES MODEL IN MULTI-INPUT MULTI-OUTPUT VIBRATION CONTROL SYSTEM

The FRF estimator based on the errors-in-variables （EV） model of multi-input multi-output （MIMO） system is presented to reduce the bias error of FRF HI estimator. The FRF HI estimator is influenced by the noises in the inputs of the system and generates an under-estimation of the true FRF. The FRF estimator based on the EV model takes into account the errors in both the inputs and outputs of the system and would lead to more accurate FRF estimation. The FRF estimator based on the EV model is applied to the waveform replication on the 6-DOF （degree-of-freedom） hydraulic vibration table. The result shows that it is favorable to improve the control precision of the MIMO vibration control system.

Research on hoarse speech based on vocal cord model and glottal waveform

Considering the fact that hoarse speech is usually caused by pathological changes of vocal cords, and its motion state is reflected by glottal waveform, we present a new method of research on hoarse speech based on dissymmetric four-mass model of vocal cords and glottal wave analysis-synthesis ill this paper. By linking hoarse speech waveform with glottal wave and the vocal cord model, the characteristic parameters of normal speech and hoarse speech before and after laryngeal operation are studied. The parameters of glottal wave periodicity and vocal cord symmetry of hoarse speech are compared with those of normal speech. It is applied to analyzing the relations between model parameters and hoarse mechanism in pathology and physiology. Experimental results show that this new method can unveil the relations between acoustic features and pathological causes of hoarse speech, providing theoretical and experimental bases both for diagnosing laryngeal diseases non-contactly and for improving the tone quality of hoarse speech.