Showing papers on "Noise published in 1977"
TL;DR: In the present study, reductions in stuttering under noise could not be explained by increases in vocal level and it appears, instead, that reductions inStuttering were related to a decrease in auditory feedback.
Abstract: The present study was designed to assess the effects of increased vocal level on stuttering in the presence and absence of noise, and to assess the effects of noise on stuttering with and without a concomitant increase in vocal level. Accordingly, eight adult stutterers spoke in quiet with normal vocal level, in quiet with increased vocal level, in noise with normal level, and in noise with increased level. All subjects reduced stuttering in noise compared with quiet conditions. However, there was no difference in stuttering when subjects spoke with normal compared with increased vocal level. In the present study, reductions in stuttering under noise could not be explained by increases in vocal level. It appears, instead, that reductions in stuttering were related to a decrease in auditory feedback. The condition which resulted in the largest decrease in auditory feedback, speaking in noise with a normal level, also resulted in the largest decrease in stuttering.
22 citations
Patent•
09 Jun 1977TL;DR: In this article, a slew-rate limited amplifier is used to reduce the interference with the voice detection process caused by impulse noise, and a logarithmic amplifier is included for the purpose of optimizing the separation of the syllabic-rate envelope from the audio signal.
Abstract: A voice detector circuit including a slew-rate limited amplifier at the input thereof so as to reduce the interference with the voice detection process caused by impulse noise. The slew-rate limited amplifier is essentially transparent to audio signals, while providing severe attenuation of impulse noise components. The actual determination of the voice content of the audio signal is provided by comparing the average syllabic-rate content of the impulse noise limited, audio signal with the peak noise content thereof. Additionally, a logarithmic amplifier is included for the purpose of optimizing the separation of the syllabic-rate envelope from the audio signal.
18 citations
TL;DR: The results indicate that psychological factors often determine the amount of annoyance, and this is in line with the concept of “noise” as a psychological, rather than an acoustical, term.
18 citations
TL;DR: White noise presented following speech initiation led to shorter reading times and fewer disfluent words, especially for part-word repetitions, and supported Timmons and Boudreau's adaptation model, which posits that stutterers have difficulty adapting to discrepancies in delays of auditory feedback through different channels.
12 citations
09 May 1977
TL;DR: The analysis of speech using Linear Prediction is reformulated to account for the presence of acoustically added noise and a technique is presented for reducing its effect on parameter estimation.
Abstract: The analysis of speech using Linear Prediction is reformulated to account for the presence of acoustically added noise and a technique is presented for reducing its effect on parameter estimation. The method, called Predictive Noise Cancellation (PNC), modifies the noisy speech autocorrelations using an estimate of present background noise which is adaptively updated from an average all-pole noise spectrum. The all-pole noise spectrum is calculated by averaging autocorrelations during non-speech activity. The method uses procedures which are already available to the LPC analyzer, and thus is well suited for real time analysis of noisy speech. Preliminary results show signal to noise improvements on the order of 10 to 20 db.
12 citations
TL;DR: It may be that the ability to match at high rates and the perception of tonal quality that subjects with excellent and trained hearing, such as musicians, exhibit for white‐spectrum stochastic pulse sequences or gated noise is due to the residue phenomenon or to spectral clues discussed in this paper.
Abstract: Data on time response in the nervous system are available for animals. Rate‐matching data for humam subjects with implanted electrodes are available. These data do not tell us with certainty up to what rate people with normal hearing utilize time information directly. In many experiments an attempt to measure time response is confused by the presence of spectral clues. Short‐term spectral clues exist in stochastic sequences of positive and negative pulses and in modulated white noise, both of which have a white long‐term spectrum. These clues are periodicity (with a period equal to the pulse or modulation rate) and symmetry (about frequencies equal to integer multiples of half this rate), differences at different frequencies in the peak‐ or rms‐voltage distribution function of the output of a narrow‐band filter and, in the case of stochastic pulse sequences, differences in extreme intensity at different frequencies. It may be that the ability to match at high rates and the perception of tonal quality that subjects with excellent and trained hearing, such as musicians, exhibit for white‐spectrum stochastic pulse sequences or gated noise is due to the residue phenomenon or to spectral clues discussed in this paper.
12 citations
TL;DR: In this article, an attempt was made to derive an impression of time duration during noise presentation, and most of the subjects showed that time may be accelerated by noise around the level of 75 dB(A), feeling that time passes faster than in silence.
11 citations
10 citations
TL;DR: In this article, the authors investigated the effect of traffic noise and air pollution on the annoyance felt by the residents of different streets with varying traffic density and building density, and found that about 40% of residents were heavily disturbed during daytime when the noise level Leq was around 65 dB(A); while for the same noise level at night about 55% reported to be heavily disturbed.
Abstract: The residents of different streets with varying traffic density and building density were questioned about annoyance due to traffic noise and air pollution. Frequency and extent of annoyance felt, effects of immissions on such living aspects as recreation, or communication, and also the reactions to the disturbance felt (such as closing windows and taking sleeping pills) were investigated. Noise levels as well as particulate matter and gaseous air pollutant concentrations were measured along the streets under investigation. The evaluation of 1300 questionaires showed that reactions to noise were different in different quarters although noise levels were the same. In general, about 40% of residents were heavily disturbed during daytime when the noise level Leq was around 65 dB(A); while for the same noise level at night about 55% reported to be heavily disturbed. Strong correlations were also obtained between annoyance due to noise and that due to air pollution. The results show that annoyance felt is dependent not only on the measured noise levels and/or air pollution concentrations, but that there do exist interactions between the residential quarters and annoyance. These interactions should be considered while fixing the limits and standards.
10 citations
Patent•
10 Jan 1977
TL;DR: In this article, the authors proposed to obtain an ensamble effect not being heard any harsh noise caused by changing a noise generated from a delay circuit to a tone color by receiving variation in an electron musical instrument.
Abstract: PURPOSE:To obtain an ensamble effect not being heard any harsh noise caused by changing a noise generated from a delay circuit to a tone color by receiving variation in an electron musical instrument.
6 citations
Patent•
29 Jan 1977
TL;DR: In this article, a group of materials such as selenium, tellurium, arsentic, and sulfer were used to reduce the noise in the time of record regeneration.
Abstract: PURPOSE:Together with manufacturing material for recording at a low cost by using such a group of materials as selenium, tellurium, tellurium containing arsentic, tellurium containing sulfer, CS2S2, OSCO2, or GaN, reducing the noise in the time of record regeneration.
TL;DR: The effects of noise on plasma renin activity (PRA) were studied in unan-esthetized rats and Stimuli at 2000 cps of up to 115 dB were ineffective in elevating PRA.
Abstract: SummaryThe effects of noise on plasma renin activity (PRA) were studied in unan-esthetized rats. An intensity of 115 dB (broadband) was required to increase PRA in animals eating a normal diet; the threshold was only 90-100 dB for sodium-deprived rats. Stimuli at 2000 cps of up to 115 dB were ineffective in elevating PRA.The authors gratefully acknowledge the advice and assistance of Dr. Joseph E. Hawkins.
Book•
01 Jan 1977
TL;DR: In this article, a strange varmint haunts the woodsman who lopped off its tail and then he opened his dogs goes to how. You know what more about the story absolutely.
Abstract: A strange varmint haunts the woodsman who lopped off its tail. Yesnothank you whimps are not themes I am happy to read. Smittys body on the mountain to get up delight for such a few. Smitty then he opened his dogs goes to how. She crawed into his belly is also said smitty yelled. This is haunted by myself remember, reading everyone else's reviews and explain that noise. You know what more about the story absolutely.
TL;DR: In this article, eight binaural chinchillas trained on a shuttlebox avoidance procedure were exposed to three successive levels of an octave band of noise centered at 0.063 kHz.
Abstract: Audiograms were obtained on eight binaural chinchillas trained on a shuttlebox avoidance procedure. Four chinchillas were exposed to three successive levels of an octave band of noise centered at 0.063 kHz: 100 dB SPL (74 dBA), 110 dB SPL (84 dBA), and 120 dB SPL (94 dBA). The other four chinchillas were exposed to these successive levels of an octave band of noise centered at 1.0 kHz: 75 dB SPL (75 dBA), 85 dB SPL (85 dBA), and 95 dB SPL (95 dBA). All exposures lasted 72 h. Maximum amounts of threshold shift (TS) of 20, 40, and 60 dB were found for the 1.0‐kHz exposures at 1.4 or 2.0 kHz. At the highest level a 10‐dB shift was present 30 days postexposure. Little TS was found for the 0. 063 kHz exposure at 100 and 110 dB. At the 120‐dB exposure a TS of about 40 dB was found at 2.0 and 4.0 kHz and 10 dB remained at 2.0 kHz 30 days postexposure. Implication for human damage risk criteria will be discussed.
TL;DR: In this article, measurements of environmental noise have been made at six sites for one-week periods in three seasons and the noise levels, expressed in six different indices, were shown to be highly correlated with each other.
TL;DR: In this paper, a method for generating a low-frequency sound program for play during the performance of a motion picture film to produce a physical effect on the theater audience is described.
Abstract: There is disclosed a method for generating a low-frequency sound program for play during the performance of a motion picture film to produce a physical effect on the theater audience. Rather than to use random low-frequency noise or some other low-frequency source which is unrelated to the audible sound program, the low-frequency program is derived by shifting down in frequency a selected portion of the audible sound program. The final low-frequency program contains frequency components below 40 Hz, at least 50% of the total energy of which is derived from the shifted-down audible program. By so harmonically relating the audible and low-frequency programs, the audio/visual and vibrational sensations are perceived in a less disjointed fashion.
Patent•
10 Jan 1977
TL;DR: In this paper, the authors proposed a level discrimination circuit for magnetic recording and reading. But this circuit requires a flip-flop to produce an output above a predetermined value for a constant period before and after falling of the output.
Abstract: PURPOSE:To remove noise having a large peak value and a small width by producing an output above a predetermined value from a flip-flop for a constant period before and after falling of the output of a level discrimination circuit for magnetic recording and reading.
TL;DR: In this article, two groups of forty subjects each were presented with three minute noise exposures, and after each noise presentation all subjects rated the annoyance of the noise, judged its acceptability, and estimated how long they could travel in the noise without discomfort.
Abstract: Two groups of forty subjects each were presented with three minute noise exposures. Test stimuli consisted of four types of interior aircraft noise (two commercial jets, general aviation, helicopter), each presented at levels of 85, 80, 75, and 70 dBA. Subjects were seated in pairs in a transportation system simulator. During the noise exposures one subject group was instructed to converse while the other group was instructed to remain silent. After each noise presentation all subjects rated the annoyance of the noise, judged its acceptability, and estimated how long they could travel in the noise without discomfort. Responses by the speech group were more critical than the reverie group on all three measures. Annoyance ratings and acceptance judgments were approximately 3 dB more severe at low noise levels and approximately 1 dB more severe at high noise levels for the speech group. [Work supported by NASA.]
TL;DR: In this article, the authors present a preliminary analysis of a survey of over 2000 people and rank several noise sources in terms of the annoyance reported by the respondents, including aircraft noise, freeway noise, and traffic noise.
Abstract: Estimates of the percentage of the US population exposed to day-night average sound levels in excess of 60 decibels indicate that while approximately 16 million people are exposed to aircraft noise and 3.6 million exposed to freeway noise, more than 59 million of the 134 million inhabitants of urban areas defined in the 1970 census are exposed to other sources of noise. The article presents a preliminary analysis of a survey of over 2000 people and rank orders several noise sources in terms of the annoyance reported by the respondents.
Journal Article•
TL;DR: Listening tests have been carried out to determine the annoyance caused by drop-outs as a function of their duration, the degree of attenuation and the frequency of occurrence, which have been applied in the DAMA annoyance meter, which can measure these quantities for an audio tape and assign a quality rating to it.
Abstract: In addition to a constant background noise, sound recordings on magnetic tape may also suffer from modulation noise and 'drop-outs'. The level of the modulation noise is proportional to that of the signa!. Modulation noise is more readily audiblein recordings of solo instruments than in orchestral music; listening tests have shown that for the flute the audibility threshold lies at a signal-to-noise ratio as high as 40 dB. The frequency with which drop-outs occur is a matter of tape quality. Listening tests have been carried out to determine the annoyance caused by drop-outs as a function oftheir duration, the degree of attenuation and the frequency of occurrence. The results of these experiments have been applied in the DAMA annoyance meter, which can measure these quantities for an audio tape and assign a quality rating to it.
Journal Article•