This paper employs direct spectral fitting of individual orbital data in order to measure rapid X-ray iron K α line and continuum spectral slope variations in Seyfert 1 galaxies with unprecedented temporal resolution. Application of this technique to a long RXTE observation of MCG−6-30-15 indicates that the line flux does vary on short (∼ <1 d) timescales, but that these variations are not corr...

A simple new method to recover details in a spectral envelope is proposed based on a recently introduced speech analysis, modification and resynthesis framework called TANDEMSTRAIGHT. Spectral envelope recovery of voiced sounds is a discrete-to-analog conversion in the frequency domain. However, there is a fundamental problem because the spatial frequency contents of vocal tract functions gener...

We investigate femtosecond stimulated Raman scattering (SRS) in H2, D2, HD, and CH4 excited with 300-fsduration pulses at 390-nm wavelength and with as much as 0.1 mJ of energy. We show that the SRSgeneration threshold and conversion efficiency are due to the transient nature of SRS in femtosecond regime. We determine optimal conditions for efficient generation in the broad spectral range 289–7...

An array of fused silica waveguiding channels with randomly distributed transverse sizes in a disordered microstructure fiber is shown to allow a highly efficient broadly tunable frequency conversion of low-energy ultrashort laser pulses. Dispersion can be switched in such waveguide arrays by coupling the pump field into waveguiding wires with different diameters. Microstructure-fiber-integrate...

Voice conversion is a process which modifies speech produced by one speaker so that it sounds as if it is uttered by another speaker. In this paper a new voice conversion system is presented. The system requires parallel training data. By using linear prediction analysis, speech is described with line spectral frequencies and the corresponding residua. LSFs are converted together with instantan...

Voice Conversion (VC) systems modify a speaker voice (source speaker) to be perceived as if another speaker (target speaker) had uttered it. Previous published VC approaches using Gaussian Mixture Models [1] performs the conversion in a frame-by-frame basis using only spectral information. In this paper, two new approaches are studied in order to extend the GMM-based VC systems. First, dynamic ...

We present results of a bright polarization-entangled photon source operating at 1552 nm via type-II collinear degenerate spontaneous parametric down-conversion in a periodically poled potassium titanyl phosphate crystal. We report a conservative inferred pair generation rate of 123,000 pairs/s/mW into collection modes. Minimization of spectral and spatial entanglement was achieved by group vel...

In this paper, a novel transcoding algorithm for the Selectable Mode Vocoder (SMV) and the G.723.1 speech coder is proposed. In contrast to the conventional tandem transcoding algorithm, the proposed algorithm converts the parameters of one coder to the other without going through the decoding and encoding process. The proposed algorithm is composed of four parts: the parameter decoding, Line S...

Voices can be deliberately disguised by means of human imitation or voice conversion. The question arises to what extent they can be modified by using either method. In the current paper, a set of speaker identification experiments are conducted; first, analysing some prosodic features extracted from voices of professional impersonators attempting to mimic a target voice and, second, using both...

We implement an interferometric method to measure the orbital angular momentum (OAM) spectrum of photon pairs generated by spontaneous parametric down-conversion. In contrast to previous experiments, which were all limited by the modal capacity of the detection system, our method operates on the entire down-conversion cone and reveals the complete distribution of the generated OAM. In this geom...