A Novel Signal-Processing Strategy Based on Bark Wavelet Transform for Cochlear Implants

2011 ◽  
Author(s):  
Yan Shen ◽  
Zhi Tao ◽  
Ji-Hua Gu ◽  
Xiao-Jun Zhang ◽  
Jun-Jie Zhu
Keyword(s):  
Signal Processing ◽  
Wavelet Transform ◽  
Cochlear Implants ◽  
Processing Strategy

Preliminary evaluation of a physiologically inspired signal processing strategy for cochlear implants

2014 ◽  
Vol 135 (4) ◽  
pp. 2410-2410 ◽  
Author(s):  
Jayaganesh Swaminathan ◽  
Raymond L. Goldsworthy ◽  
Patrick M. Zurek ◽  
Agnès C. Léger ◽  
Louis D. Braida
Keyword(s):  
Signal Processing ◽  
Cochlear Implants ◽  
Preliminary Evaluation ◽  
Processing Strategy

scholarly journals A Daily Alternating Method for Comparing Different Signal-Processing Strategies in Hearing Aids and in Cochlear Implants

2008 ◽  
Vol 19 (05) ◽  
pp. 443-454 ◽  
Author(s):  
Richard S. Tyler ◽  
Shelley A. Witt ◽  
Camille C. Dunn ◽  
Ann E. Perreau
Keyword(s):  
Signal Processing ◽  
Cochlear Implants ◽  
Hearing Aids ◽  
Daily Basis ◽  
The Other ◽  
Processing Strategy ◽  
Clear Advantage ◽  
Processing Strategies ◽  
Listening Experience ◽  
Post Trial

Background: Although we always want to select the best signal-processing strategy for our hearing-aid and cochlear-implant patients, no efficient and valid procedure is available. Comparisons in the office are without listening experience, and short-term take-home trials are likely influenced by the order of strategies tried. Purpose: The purpose of this study was to evaluate a new procedure for comparing signal-processing strategies whereby patients listen with one strategy one day and another strategy the next day. They continue this daily comparison for several weeks. We determined (1) if differences existed between strategies without prior listening experience and (2) if performance differences (or lack there of) obtained at the first listening experience are consistent with performance after two to three months of alternating between strategies on a daily basis (equal listening experience). Research Design: Eight subjects were tested pretrial with a vowel, sentence, and spondee recognition test, a localization task, and a quality rating test. They were required to listen to one of two different signal processing strategies alternating between strategies on a daily basis. After one to three months of listening, subjects returned for follow-up testing. Additionally, subjects were asked to make daily ratings and comments in a diary. Results: Pre-trial (no previous listening experience), a clear trend favoring one strategy was observed in four subjects. Four other subjects showed no clear advantage. Post-trial (after alternating daily between strategies), of the four subjects who showed a clear advantage for one signal processing strategy, only one subject showed that same advantage. One subject ended up with an advantage for the other strategy. Post-trial, of the four subjects who showed no advantage for a particular signal processing strategy, three did show an advantage for one strategy over the other. Conclusion: Patients are willing to alternate between signal processing strategies on a daily basis for up to three months in an attempt to determine their optimal strategy. Although some patients showed superior performance with initial fittings (and some did not), the results of pre-trial comparison did not always persist after having equal listening experience. We recommend this daily alternating listening technique when there is interest in determining optimal performance among different signal processing strategies when fitting hearing aids or cochlear implants.

A New Application of Continuous Wavelet Transform to Overlapping Chromatograms for the Quantitative Analysis of Amiloride Hydrochloride and Hydrochlorothiazide in Tablets by Ultra-Performance Liquid Chromatography

2012 ◽  
Vol 95 (3) ◽  
pp. 751-756 ◽  
Author(s):  
Erdal Dinç ◽  
Eda Büker
Keyword(s):  
Signal Processing ◽  
Wavelet Transform ◽  
Quantitative Analysis ◽  
Continuous Wavelet Transform ◽  
Standard Addition ◽  
Ultra Performance Liquid Chromatography ◽  
Continuous Wavelet ◽  
Constant Flow Rate ◽  
Acquity Uplc ◽  
Amiloride Hydrochloride

Abstract A new application of continuous wavelet transform (CWT) to overlapping peaks in a chromatogram was developed for the quantitative analysis of amiloride hydrochloride (AML) and hydrochlorothiazide (HCT) in tablets. Chromatographic analysis was done by using an ACQUITY ultra-performance LC (UPLC) BEH C18 column (50 × 2.1 mm id, 1.7 μm particle size) and a mobile phase consisting of methanol–0.1 M acetic acid (21 + 79, v/v) at a constant flow rate of 0.3 mL/min with diode array detection at 274 nm. The overlapping chromatographic peaks of the calibration set consisting of AML and HCT mixtures were recorded rapidly by using an ACQUITY UPLC H-Class system. The overlapping UPLC data vectors of AML and HCT drugs and their samples were processed by CWT signal processing methods. The calibration graphs for AML and HCT were computed from the relationship between concentration and areas of chromatographic CWT peaks. The applicability and validity of the improved UPLC-CWT approaches were confirmed by recovery studies and the standard addition technique. The proposed UPLC-CWT methods were applied to the determination of AML and HCT in tablets. The experimental results indicated that the suggested UPLC-CWT signal processing provides accurate and precise results for industrial QC and quantitative evaluation of AML-HCT tablets.

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