Noise

About: Noise is a research topic. Over the lifetime, 5111 publications have been published within this topic receiving 69407 citations. The topic is also known as: Мопсы танцуют под радио бандитов из сталкера 10 часов.

Method and apparatus for automatic control of spectral doppler imaging

Abstract: An ultrasound system is disclosed that includes a method and apparatus to automatically adjust certain parameters that affect visualization of a Doppler spectral image. The ultrasound system acquires spectral lines of Doppler data generated by the ultrasound system. A data processor within the ultrasound system determines the presence of aliasing and estimates noise levels from the spectral lines of Doppler data. The data processor then automatically adjusts system parameters such as pulse repetition frequency (PRF), baseline shift, and spectrum orientation in response to aliasing and noise levels. The data processor of the ultrasound system also determines positive and negative signal boundaries for each spectral line of Doppler data and a display architecture processes the signal boundary data to display a spectral trace corresponding to the edges of the spectral lines.

The Effects of Negative Affect Arousal on Reactions to Speakers

Abstract: Two studies were conducted to test the hypothesis that speakers associated with negative affect and/or frustration will be negatively evaluated. As part of a colour recognition study, the participants in the first experiment listened to tape-recorded colour descriptions by a male speaker of standard English . The tape was either free from noise or punctuated by bursts of white noise. The subjects in the noisy tape condition performed significantly worse on the colour recognition task, and consistent with the hypothesis, judged the speaker less favourably. Participants in the second study listened to the colour descriptions of either a standard or Spanish-accented speaker of English which were presented on tapes with no noise, continuous white noise or bursts of white noise. Colour recognition accuracy was significantly influenced by both noise and accent alone as well as in combination. Accented speakers were responded to more negatively than standard speakers on most measures, including several social evaluation scales. Noise significantly affected other measures, including the ratings of speaker's communication effectiveness, tape responsibility for task difficulty, and ease of understanding. The results, as a whole, suggest that serious attention be given to the negative affect mechanism in the social evaluation of nonstandard speech styles.

Remote power supply

Abstract: A remote power supply arrangement for graphical display systems. The remote power supply places one or more power supplies in a separate location, some distance apart from the graphical display, rather than within the display cabinet or module itself. Power is then transferred from the power supply to the display by electrical cords. The remote power supply provides lighter weight displays, less noise near the displays, and improved maintenance and repair. The invention includes apparatus, methods of providing remote power to displays.

Signal and Feature Compensation Methods for Robust Speech Recognition

Abstract: Automatic speech recognition systems are pattern classifiers designed to solve a rather specific statistical pattern classification problem. For the benefit of readers with a limited background in speech recognition technologies, this chapter begins by reviewing the formulation of automatic speech recognition as a statistical pattern classification process and by discussing how environmental disturbances adversely affect classifier performance. Linear spectral subtraction, also referred to simply as spectral subtraction, is a method of canceling additive uncorrelated noise from a noisy speech signal. In spectral subtraction, signals are separated into speech and nonspeech regions by a variety of techniques, and all regions deemed to be nonspeech are used to estimate the noise spectrum. Nonlinear spectral subtraction attempts to improve the noise cancellation of spectral subtraction by making the oversubtraction factor for any frequency band dependent on the local signal-to-noise ratio. The chapter describes selected signal and feature compensation techniques in current usage, which were chosen on the basis of their efficiency and generality.

A current-mode power sigma-delta modulator for audio applications

Abstract: Linear and switching techniques are currently adopted to implement current-mode power stages. Pulsewidth modulation (PWM) is usually employed with the switching technique for both industrial and audio applications. In this paper, the Sigma-Delta modulation is considered as an alternative to the PWM in devising a switching current-mode power stage suitable for audio amplification. The proposed modulator is analyzed and simulated. The whole system was realized on an experimental breadboard. The results carried out on the prototype are reported and discussed. The electrical characterization presents interesting features in terms of linearity, noise, and power efficiency.