Developing Models and Algorithms for Studying the Effects of Nonlinear Frequency Dispersion in Transiono-spheric Communication Channels with Dispersion Distortions

The paper represents the mathematical model for diagnostics of supercapacitors. The research objectives are the problem of determining a supercapacitor technical condition during its operation. The general reliability of diagnostics is described as the methodological and instrumental reliabilities of diagnostics. The instrumental diagnostic reliability of supercapacitor includes the probabilities of errors of the first and second kind, α and β respectively. The methodological approach to increasing the reliability of supercapacitor diagnostic has been proposed, in terms of multi-parameter supercapacitor diagnostic by applying nonlinear, frequency dependent mathematical models of supercapacitors that take into account nonlinearity, frequency dispersion of parameters and the effect of transient processes in supercapacitors. The more frequencies, operating voltages and currents are applied in the supercapacitor diagnostics, the more methodological reliability of diagnostics will increase in relation to the methodological reliability of supercapacitor diagnostics when only one frequency, voltage and current are applied.

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Method of Training Mode of Adaptive System for Frequency Dispersion Correction in Wideband Ionospheric HF Communication Channels

2019 Wave Electronics and its Application in Information and Telecommunication Systems (WECONF) ◽

10.1109/weconf.2019.8840628 ◽

2019 ◽

Cited By ~ 3

Author(s):

D. V. Ivanov ◽

V. A. Ivanov ◽

V. V. Ovchinnikov ◽

M. I. Ryabova

Keyword(s):

Adaptive System ◽

Communication Channels ◽

Frequency Dispersion ◽

Dispersion Correction ◽

Training Mode

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The S-SH Confusion Test and the Effects of Frequency Lowering

Journal of Speech Language and Hearing Research ◽

10.1044/2018_jslhr-h-18-0267 ◽

2019 ◽

Vol 62 (5) ◽

pp. 1486-1505

Author(s):

Joshua M. Alexander

Keyword(s):

Cognitive Processing ◽

Hearing Aids ◽

Response Times ◽

Nonlinear Frequency ◽

Low Frequencies ◽

Frequency Compression ◽

Negative Side ◽

Minimal Word ◽

Low Pass ◽

Negative Side Effects

PurposeFrequency lowering in hearing aids can cause listeners to perceive [s] as [ʃ]. The S-SH Confusion Test, which consists of 66 minimal word pairs spoken by 6 female talkers, was designed to help clinicians and researchers document these negative side effects. This study's purpose was to use this new test to evaluate the hypothesis that these confusions will increase to the extent that low frequencies are altered.MethodTwenty-one listeners with normal hearing were each tested on 7 conditions. Three were control conditions that were low-pass filtered at 3.3, 5.0, and 9.1 kHz. Four conditions were processed with nonlinear frequency compression (NFC): 2 had a 3.3-kHz maximum audible output frequency (MAOF), with a start frequency (SF) of 1.6 or 2.2 kHz; 2 had a 5.0-kHz MAOF, with an SF of 1.6 or 4.0 kHz. Listeners' responses were analyzed using concepts from signal detection theory. Response times were also collected as a measure of cognitive processing.ResultsOverall, [s] for [ʃ] confusions were minimal. As predicted, [ʃ] for [s] confusions increased for NFC conditions with a lower versus higher MAOF and with a lower versus higher SF. Response times for trials with correct [s] responses were shortest for the 9.1-kHz control and increased for the 5.0- and 3.3-kHz controls. NFC response times were also significantly longer as MAOF and SF decreased. The NFC condition with the highest MAOF and SF had statistically shorter response times than its control condition, indicating that, under some circumstances, NFC may ease cognitive processing.ConclusionsLarge differences in the S-SH Confusion Test across frequency-lowering conditions show that it can be used to document a major negative side effect associated with frequency lowering. Smaller but significant differences in response times for correct [s] trials indicate that NFC can help or hinder cognitive processing, depending on its settings.

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