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R N Kasten

Publications and source records attributed to R N Kasten.

12 recordsLinked to original sources
PubMed1994

Prediction of 8-hour noise dose from brief duration samples.

The purpose of this study was to determine whether brief duration samples of noise dose measurements could predict the noise exposure levels of employees as measured by 8-hour dosimetry. Sampled noise dose measurements were obtained for 1, 5, 10, 15, and 20 minutes and 8 hours for four workers at each of four industrial sites. Statistical analyses indicated no significant differences or interactions among trials and sample durations. A simple linear prediction model provided the best fit for the four shortest of the five abbreviated sample durations, whereas an exponential regression model provided the best predictions using the 20-minute sample duration. The high variance and low correlations across all measures permitted only poor predictions from these abbreviated sample data. Based on these results, sampled noise measurements of short duration (1 to 20 minutes) do not appear to be a valid means for predicting the amount of noise exposure during an 8-hour shift.

Acoustic Stimulation↗
PubMed1981

Effects of stimulus frequency, level, and duration on auditory temporal ordering.

Auditory temporal ordering was investigated in 5 normal-hearing young adults. Ss made diotic 2IFC judgments for pure tones of 0.5, 1, 2, or 4 kc/s and critical-band noises centered at those frequencies, on duration (standard: 40 msec; variables: 10, 20, or 30 msec), level (standard: 70 db HL; variables: 40, 50 or 60 HL), and frequency (standard: 0.5 kc/s; variables: 1,2, or 4 kc/s). Interstimulus interval (ISI) was 5, 10, 20, 50, 100, or 200 msec. All stimuli were at 70 db HL except of course the variable stimuli in the level judgments. Performance improved with increasing ISI. Mean threshold ISIs (performance at 75%-correct) collapsed across pure tones and noise bands were 12.5, 6.25, and 6.25 msec for duration, level, and frequency, respectively. With ISI constant at 100 msec, ANOVAs revealed statistically significant differences among the variables for duration and for level but not for frequency (performance for frequency was nearly perfect at the shortest ISI). There were statistically significant differences between mean performance, and between mean threshold ISIs, for duration, level, and frequency, indicating that auditory temporal acuity is not independent of the kinds of sound, as has been suggested (Hirsh, J. Acoust. Soc. Am., 1959, 31, p. 759).

Adult↗
PubMedDate not supplied

Threshold improvement and acoustic gain with hearing aids.

Aided speech reception thresholds were obtained from 20 hearing-impaired listeners with three hearing aids adjusted to confort settings, and with the aids adjusted to deliver 40 dB of acoustic gain. The aided speech reception threshold under each condition was substracted from the unaided speech reception threshold to yield a measure of threshold improvement. Threshold improvement and acoustic gain comparisons revealed that, at comfort setting, these two measures were quite similar. However, at the 40-dB gain setting, acoustic gain exceeded threshold improvement by an average of 5.6 dB. For the high-gain condition, it appeared that the threshold improvement obtained by subjects with relatively good unaided sensitivity was limited by the ambient noise in the test chamber.

Acoustic Stimulation↗