摘要:
A method and system for generating an estimate of a clean speech signal extracts time trajections of short-term parameters from a noisy speech signal to obtain a plurality of frequency components each having a magnitude spectrum and a phase spectrum. The magnitude spectrum is then compressed, filtered and then decompressed to obtain a modified magnitude spectrum. The speech signal is then reconstructed using the original phase spectrum and the modified magnitude spectrum.
摘要:
A binary, boron-based alloy as a source for field-emission-type, ion-beam generating devices, wherein boron predominates in the alloy, preferably with a presence of about 60 atomic percent. The other constituent in the alloy is selected from the group of elements consisting of nickel, palladium and platinum. Predominance of boron in these alloys, during operation, promotes combining of boron with trace impurities of carbon in the alloys to form B.sub.4 C and thus to promote wetting of an associated carbon support substrate.
摘要:
A method for modulating a liquid metal ion source includes generating an ion beam, directing a light beam at the liquid metal ion source and inducing a modulation in the ion beam by modulating the light beam.An apparatus for carrying out the invention includes a light beam source for generating a light beam, a modulator for modulating the light beam and a mechanism for directing the modulated light beam at the light metal ion source.
摘要:
A method and system for adaptively filtering a speech signal in order to suppress noise in the signal. The method includes decomposing the signal into multiple frequency subbands, each having a center frequency, estimating a signal-to-noise ratio for each subband, and providing multiple filters, each filter designed for one of a number of selected signal-to-noise ratio independent of the center frequencies of the subbands. The method also includes selecting a filter for filtering each subband, where the filter selected depends on the signal-to-noise ratio estimated for the subband, filtering each subband according to the filter selected, and combining the filtered subbands to provide an estimated filtered speech signal. The system includes appropriate hardware and software for performing the method.
摘要:
The apparatus of the present invention includes a light source for producing a coherent beam of light. A beam splitter is provided for splitting the beam of light into a first, transmitted beam segment and a second, local oscillator beam. A mechanism is provided for frequency shifting the frequency of one or both beam segments and for directing the first beam segment to a target. A remote target for scattering the first beam is provided. A mechanism is provided for combining the scattered first beam segment returning from the target and the second beam segment into a combined beam, and detecting the combined beam. A detector is operative to generate a signal indicative of the crosswind along the path of the directed first beam segment. A mechanism for determining the wind speed normal to the path from the generated signal is also provided.