A speech processor providing fricative and low-frequency periodicity information for single channel cochlear prosthesis

Author(s):  
P. Pandey ◽  
H. Kunov ◽  
S. Abel
Geophysics ◽  
2006 ◽  
Vol 71 (3) ◽  
pp. V79-V86 ◽  
Author(s):  
Hakan Karsli ◽  
Derman Dondurur ◽  
Günay Çifçi

Time-dependent amplitude and phase information of stacked seismic data are processed independently using complex trace analysis in order to facilitate interpretation by improving resolution and decreasing random noise. We represent seismic traces using their envelopes and instantaneous phases obtained by the Hilbert transform. The proposed method reduces the amplitudes of the low-frequency components of the envelope, while preserving the phase information. Several tests are performed in order to investigate the behavior of the present method for resolution improvement and noise suppression. Applications on both 1D and 2D synthetic data show that the method is capable of reducing the amplitudes and temporal widths of the side lobes of the input wavelets, and hence, the spectral bandwidth of the input seismic data is enhanced, resulting in an improvement in the signal-to-noise ratio. The bright-spot anomalies observed on the stacked sections become clearer because the output seismic traces have a simplified appearance allowing an easier data interpretation. We recommend applying this simple signal processing for signal enhancement prior to interpretation, especially for single channel and low-fold seismic data.


2021 ◽  
Vol 9 (1) ◽  
pp. 70
Author(s):  
Pareng Rengi ◽  
Ulil Amri ◽  
Tomi Ramadona ◽  
Ediar Usman ◽  
Bustari Bustari

<p>Aruah Islands is located on an international shipping line adjacent to Malaysia. The important aspect in borderline management is the maritime resource potential, one of which is sea minerals. In order to dig the information about marine mineral resources in Aruah Islands, a high-resolution seismic reflection with low frequency was applied, which capable to detect the depth and identify the sedimentary layers clearly and accurately. The depth of water and sediment layers were detected using an echosounder, reason Navi sound type 210 with a tow fish 100 kHz and shallow seismic boomer with a single channel type and wave energy 200 Joules. Gravity core and grab sampler were used to collect the sediment sample. There were three stages on seismic interpretation: sequence analysis, facies analysis, and reflection character identification. Furthermore, sediments containing coarse sand-sized minerals were observed using a microscope. The measurement result of Aruah Islands water depth was ranging from 0-80 m, the deepest part is on the Northern of Batu Mandi island which was 80 m depth. Seismic profiles indicated that the upper layer of tertiary sedimentary as the youngest rocks. Based on sediment thickness, the thickest area was found on the Western (approx. 50 m) and the Northern (approx. 32 m). In line with the island’s Southern part condition, which was plain or shallow sea exposure, the Southeastern island sediment thickness ranged only about 10-18 m. Generally, based on the analyzed sediment sample, quartz was the main mineral found, which was 60-80% of the composition. Other minerals were zircon, tin, hematite, magnetite, limonite, biotite, and dolomite.</p>


1987 ◽  
Vol 96 (4) ◽  
pp. 349-361 ◽  
Author(s):  
Mark J. Maslan ◽  
Josef M. Miller

As a result of practical considerations, histopathologic findings of the temporal bone in humans with cochlear prosthesis implants have been limited. This project attempts to better define safe parameters of electrical stimulation of the inner ear and compare the safe limits of intracochlear vs. extracochlear stimulation sites. Guinea pigs were implanted with single electrodes either on the promontory or in the scala tympani and were stimulated relative to a remote indifferent for 12 hours distributed over a 4-week period. Electrical auditory brainstem evoked responses (EABRs) were tested before and after each of four 3-hour stimulation sessions. Six weeks after implantation, the animals were killed, and their cochleas were examined under the scanning electron microscope. Intracochlear electrodes exhibited thresholds for damage well below one half of that found for most extracochlear stimulation sites. The function-relating damage threshold (in amperes) to frequency of intracochlear stimulation is represented by two straight lines, with an intercept of 1 kHz. The low-frequency limb exhibited a slope of 3 to 4 dB/octave, whereas the high-frequency limb exhibited a slope of 9 to 10 dB/octave. Extracochlear results were too variable to permit speculation. Changes in EABRs were only variably related to histopathologic findings.


1992 ◽  
Vol 13 (03) ◽  
pp. 254-259
Author(s):  
Lois Sutton ◽  
Herman Jenkins ◽  
Newton Coker

1987 ◽  
Vol 96 (1_suppl) ◽  
pp. 150-151 ◽  
Author(s):  
R. C. Lindeman ◽  
C. A. Mangham ◽  
S. V. Kuprenas

We compared House single-channel and Nucleus multichannel cochlear prosthesis performance in the same individual. The Minimal Auditory Capabilities (MAC) battery was used to assess performance. In most instances, the reimplanted Nucleus device was equivalent to or outperformed the original House prosthesis, and compared favorably with reported data from a group of multichannel users. Results from this case tend to support the feasibility of explanting a House device and reimplanting a Nucleus prosthesis without a measurable decrement in performance.


1987 ◽  
Vol 96 (1_suppl) ◽  
pp. 74-76
Author(s):  
J. R. Walliker ◽  
A. J. Fourcin

We have developed a family of single-channel signal-processing aids for the profoundly and totally deaf. Common to them all are the analysis of speech into the components most important to the deaf lipreader; the synthesis of stimuli which make the best use of the patient's sensory abilities; and facilities to ensure accurate matching of the aid to the patient. The totally deaf are electrically stimulated by electrodes on the promontory or on the round window of the cochlea using charge-balanced controlled current square waves automatically adjusted to be at a comfortable level. Many potential candidates for electrocochlear stimulation have significant low frequency residual hearing, but do not find conventional hearing aids to be useful. We have found that they can often make very effective use of the voice fundamental frequency presented as an acoustic sinusoid. Our approach to these patients avoids the need for implant surgery but preserves that option should total loss of hearing occur in the future. Both electrocochlear and acoustic methods of signal presentation are implemented with similar hardware. The speech signal from a microphone or other source is analyzed by a voice fundamental frequency extractor and a voiceless sound detector. Their outputs are processed by a single chip microcomputer that synthesizes the output waveform. In both devices the aid is tailored to the patient using a desktop computer that stores amplitude-frequency characteristics and frequency mapping tables into a read-only memory.


2014 ◽  
Vol 624 ◽  
pp. 561-566
Author(s):  
Jun Wang ◽  
Shuo Feng

The paper introduces a system using PLL frequency modulation and demodulation technique, and using infrared as the carrier to realize wireless communication. CD4046 is a common CMOS low-frequency phase locked loopintegrated circuit, and it has the characteristics of high VCOlinearity, tunable center frequency and acquisition frequency range, low power consumption and simple for use. The paper introduces the design scheme using the technique for infrared communication, and proposes a method using sing-chip microcontroller to control single channel to realize the simultaneous transmission of acoustic signal and digital signal, which has great practicability.


1987 ◽  
Vol 96 (1_suppl) ◽  
pp. 129-132 ◽  
Author(s):  
R. D. Battmer ◽  
E. Lehnhardt ◽  
R. Laszig

Successful implantation of a cochlear implant requires a healthy auditory nerve. Subjective and qualitative data can be obtained by means of promontory testing (PT). Cochlear microphonics (CM) in electrocochleography, on the other hand, gives information about the status of the hair cells in the inner ear. The results of both tests together can indicate the feasibility of an implant in cases of sensory deafness (PT positive, no CM), while other combinations help to localize the origin of the deafness, eg, neural or sensorineural. Therefore, the reliability of results is extensive and almost doubly guaranteed. To answer the question of using single-channel or multichannel cochlear implants we decided to use the 22-channel Nucleus device. The digital working system consists of the implanted receiver-stimulator and external speech processor. To date we have implanted 14 patients. In all of them, the electrode array could be inserted easily, and the threshold and comfortable levels could be adjusted very fast. The dynamic range showed a growth in the first weeks after the operation. Results of 11 of our patients are presented. They show that 1) speech-tracking scores with the processor are much higher than with lipreading only; 2) lipreading ability remains constant; 3) the understanding of vowels and consonants with the speech processor is much better; and 4) three of our patients reached scores between 20 and 30 words per minute with hearing alone for speech tracking.


Sign in / Sign up

Export Citation Format

Share Document