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Fulltext Classification of abnormal location in medium voltage switchgears using hybrid gravitational search algorithm-artificial intelligence

Illias HA, Lim MM, Abu Bakar AH, Mokhlis H, Ishak S, Amir MDM

PLoS One, 2021;16(7):e0253967.
PMID: 34197530 DOI: 10.1371/journal.pone.0253967

In power system networks, automatic fault diagnosis techniques of switchgears with high accuracy and less time consuming are important. In this work, classification of abnormal location in switchgears is proposed using hybrid gravitational search algorithm (GSA)-artificial intelligence (AI) techniques. The measurement data were obtained from ultrasound, transient earth voltage, temperature and sound sensors. The AI classifiers used include artificial neural network (ANN) and support vector machine (SVM). The performance of both classifiers was optimized by an optimization technique, GSA. The advantages of GSA classification on AI in classifying the abnormal location in switchgears are easy implementation, fast convergence and low computational cost. For performance comparison, several well-known metaheuristic techniques were also applied on the AI classifiers. From the comparison between ANN and SVM without optimization by GSA, SVM yields 2% higher accuracy than ANN. However, ANN yields slightly higher accuracy than SVM after combining with GSA, which is in the range of 97%-99% compared to 95%-97% for SVM. On the other hand, GSA-SVM converges faster than GSA-ANN. Overall, it was found that combination of both AI classifiers with GSA yields better results than several well-known metaheuristic techniques.

Matched MeSH terms: Sound
Serum testosterone, sex hormone-binding globulin and total calcium levels predict the calcaneal speed of sound in men

Chin KY, Soelaiman IN, Mohamed IN, Ngah WZ

Clinics (Sao Paulo), 2012 Aug;67(8):911-6.
PMID: 22948459

OBJECTIVES: Variations in sex hormones and the calcium balance can influence bone health in men. The present study aimed to examine the relationship between the calcaneal speed of sound and biochemical determinants of bone mass, such as sex hormones, parathyroid hormones and serum calcium.
METHODS: Data from 549 subjects from the Malaysian Aging Male Study, which included Malay and Chinese men aged 20 years and older residing in the Klang Valley, were used for analysis. The subjects' calcaneal speed of sound was measured, and their blood was collected for biochemical analysis. Two sets of multiple regression models were generated for the total/bioavailable testosterone and estradiol to avoid multicollinearity.
RESULTS: The multiple regression results revealed that bioavailable testosterone and serum total calcium were significant predictors of the calcaneal speed of sound in the adjusted model. After adjustment for ethnicity and body mass index, only bioavailable testosterone remained significant; the total serum calcium was marginally insignificant. In a separate model, the total testosterone and sex hormone-binding globulin were significant predictors, whereas the total serum calcium was marginally insignificant. After adjustment for ethnicity and body mass index (BMI), the significance persisted for total testosterone and SHBG. After further adjustment for age, none of the serum biochemical determinants was a significant predictor of the calcaneal speed of sound.
CONCLUSION: There is a significant age-dependent relationship between the calcaneal speed of sound and total testosterone, bioavailable testosterone and sex hormone-binding globulin in Chinese and Malay men in Malaysia. The relationship between total serum calcium and calcaneal speed of sound is ethnicity-dependent.

Matched MeSH terms: Sound*
Vocal acoustics in the endangered proboscis monkey (Nasalis larvatus)

Röper KM, Scheumann M, Wiechert AB, Nathan S, Goossens B, Owren MJ, et al.

Am J Primatol, 2014 Feb;76(2):192-201.
PMID: 24123122 DOI: 10.1002/ajp.22221

The endangered proboscis monkey (Nasalis larvatus) is a sexually highly dimorphic Old World primate endemic to the island of Borneo. Previous studies focused mainly on its ecology and behavior, but knowledge of its vocalizations is limited. The present study provides quantified information on vocal rate and on the vocal acoustics of the prominent calls of this species. We audio-recorded vocal behavior of 10 groups over two 4-month periods at the Lower Kinabatangan Wildlife Sanctuary in Sabah, Borneo. We observed monkeys and recorded calls in evening and morning sessions at sleeping trees along riverbanks. We found no differences in the vocal rate between evening and morning observation sessions. Based on multiparametric analysis, we identified acoustic features of the four common call-types "shrieks," "honks," "roars," and "brays." "Chorus" events were also noted in which multiple callers produced a mix of vocalizations. The four call-types were distinguishable based on a combination of fundamental frequency variation, call duration, and degree of voicing. Three of the call-types can be considered as "loud calls" and are therefore deemed promising candidates for non-invasive, vocalization-based monitoring of proboscis monkeys for conservation purposes.

Matched MeSH terms: Sound Spectrography
Fulltext Effects of thermosonication on the fate of Escherichia coli O157:H7 and Salmonella Enteritidis in mango juice

Kiang WS, Bhat R, Rosma A, Cheng LH

Lett Appl Microbiol, 2013 Apr;56(4):251-7.
PMID: 23278854 DOI: 10.1111/lam.12042

In this study, the effects of thermosonication and thermal treatment on Escherichia coli O157:H7 and Salmonella Enteritidis in mango juice were investigated at 50 and 60°C. Besides, nonlethal injury of Salm. Enteritidis after both treatments was also examined. The highest inactivation was attained with thermosonication at 60°C. The inactivation rate was different for both pathogens, and Salm. Enteritidis was found to be more sensitive to thermosonication than E. coli O157:H7. Salmonella Enteritidis was recovered in all treated samples, except those subjected to more than 5-min thermosonication at 60°C. It was found that the introduction of high-intensity ultrasound enhanced the inactivation of pathogens compared to thermal treatment alone. On the other hand, Salm. Enteritidis was detected in a number of samples following incubation in universal pre-enrichment broth, but no growth was detected after incubation in mango juice.

Matched MeSH terms: Sound
Sound production in the tiger-tail seahorse Hippocampus comes: Insights into the sound producing mechanisms

Lim AC, Chong VC, Chew WX, Muniandy SV, Wong CS, Ong ZC

J Acoust Soc Am, 2015 Jul;138(1):404-12.
PMID: 26233039 DOI: 10.1121/1.4923153

Acoustic signals of the tiger-tail seahorse (Hippocampus comes) during feeding were studied using wavelet transform analysis. The seahorse "click" appears to be a compounded sound, comprising three acoustic components that likely come from two sound producing mechanisms. The click sound begins with a low-frequency precursor signal, followed by a sudden high-frequency spike that decays quickly, and a final, low-frequency sinusoidal component. The first two components can, respectively, be traced to the sliding movement and forceful knock between the supraorbital bone and coronet bone of the cranium, while the third one (purr) although appearing to be initiated here is produced elsewhere. The seahorse also produces a growling sound when under duress. Growling is accompanied by the highest recorded vibration at the cheek indicating another sound producing mechanism here. The purr has the same low frequency as the growl; both are likely produced by the same structural mechanism. However, growl and purr are triggered and produced under different conditions, suggesting that such "vocalization" may have significance in communication between seahorses.

Matched MeSH terms: Sound
Fulltext Monthly distribution map of carbon monoxide (CO) from AIRS over Peninsular Malaysia, Sabah and Sarawak for the year 2003

Jasim M. Rajab, Mat Jafri, M.Z, Lim, H.S., Abdullah, K.

Pertanika Journal of Science & Technology, 2011;19(3):89-96.
MyJurnal

Carbon monoxide (CO) is a ubiquitous, an indoor and outdoor air pollutant. It is not a significant greenhouse gas as it absorbs little infrared radiation from the Earth. It is produced by the incomplete combustion of fossil fuels, and biomass burning. The CO data are obtained from Atmospheric Infrared Sounder (AIRS) onboard NASA’s Aqua satellite. The AIRS provides information for several greenhouse gases, CO2, CH4, CO, and O3 as a one goal of the AIRS instrument (included on the EOS Aqua satellite launched, May 4, 2002) as well as to improve weather prediction of the water and energy cycle. The results of the analysis of the retrieved CO total column amount (CO_total_column_A) as well as effective of the CO volume mixing ratio (CO_VMR_eff_A), Level-3 monthly (AIR*3STM) 1º*1º spatial resolution, ascending are used to study the CO distribution over the East and West Malaysia for the year 2003. The CO maps over the study area were generated by using Kriging Interpolation technique and analyzed by using Photoshop CS. Variations in the biomass burning and the CO emissions where noted, while the highest CO occurred at late dry season in the region which has experienced extensive biomass burning and greater draw down of CO occurred in the pristine continental environment (East Malaysia). In all cases, the CO concentration at West Malaysia is higher than East Malaysia. The southeastern Sarawak (lat. 3.5˚ - long. 115.5˚) is less polluted regions and less the CO in most of times in the year. Examining satellite measurements revealed that the enhanced CO emission correlates with occasions of less rainfall during the dry season.

Matched MeSH terms: Sound
The equivalent threshold sound pressure levels and test-retest threshold variability of a consumer-grade insert earphone fitted with stock, foam, and otoacoustic emission probe ear tips

Seluakumaran K, Kamal Azizi A, Kulasegarah J

Int J Audiol, 2024 Jul;63(7):551-559.
PMID: 37139683 DOI: 10.1080/14992027.2023.2205008

OBJECTIVE: Consumer-grade insert earphones (IEs) can be utilised for audiometry, but their calibration values and threshold reliability may differ from the audiometric IE. This study measured the equivalent threshold sound pressure levels (ETSPLs), and the test-retest threshold variation when a consumer IE (Sennheiser CX100) was fitted with: (1) silicone stock ear tips that came along with the earphone, (2) replacement foam ear tips (KZ acoustics) and (3) silicone otoacoustic emission (OAE) probe ear tips.
DESIGN AND STUDY SAMPLE: Study 1 determined ETSPL values in 25 normal-hearing subjects aged 18-25 years at seven test frequencies (500-8000 Hz). Study 2 assessed the intra- and inter-session test-retest threshold reliability in a separate group of 50 adult subjects.
RESULTS: The ETSPL values for the consumer IE deviated from the reference values for audiometric IEs, with the largest differences (7-9 dB) observed at 500 Hz across ear tips. This is likely related to shallow tip insertions. However, test-retest threshold variations were comparable to those reported for audiometric transducers.
CONCLUSIONS: Ear tip-specific corrections to the reference thresholds in the standards are required for calibration of consumer IEs used in low-cost audiometry when their ear tips only allow superficial insertion into the ear canal.

Matched MeSH terms: Sound
Fulltext Updated parameters and expanded simulation options for a model of the auditory periphery

Zilany MS, Bruce IC, Carney LH

J Acoust Soc Am, 2014 Jan;135(1):283-6.
PMID: 24437768 DOI: 10.1121/1.4837815

A phenomenological model of the auditory periphery in cats was previously developed by Zilany and colleagues [J. Acoust. Soc. Am. 126, 2390-2412 (2009)] to examine the detailed transformation of acoustic signals into the auditory-nerve representation. In this paper, a few issues arising from the responses of the previous version have been addressed. The parameters of the synapse model have been readjusted to better simulate reported physiological discharge rates at saturation for higher characteristic frequencies [Liberman, J. Acoust. Soc. Am. 63, 442-455 (1978)]. This modification also corrects the responses of higher-characteristic frequency (CF) model fibers to low-frequency tones that were erroneously much higher than the responses of low-CF model fibers in the previous version. In addition, an analytical method has been implemented to compute the mean discharge rate and variance from the model's synapse output that takes into account the effects of absolute refractoriness.

Matched MeSH terms: Sound Spectrography
Emotional speech acoustic model for Malay: iterative versus isolated unit training

Mustafa MB, Ainon RN

J Acoust Soc Am, 2013 Oct;134(4):3057-66.
PMID: 24116440 DOI: 10.1121/1.4818741

The ability of speech synthesis system to synthesize emotional speech enhances the user's experience when using this kind of system and its related applications. However, the development of an emotional speech synthesis system is a daunting task in view of the complexity of human emotional speech. The more recent state-of-the-art speech synthesis systems, such as the one based on hidden Markov models, can synthesize emotional speech with acceptable naturalness with the use of a good emotional speech acoustic model. However, building an emotional speech acoustic model requires adequate resources including segment-phonetic labels of emotional speech, which is a problem for many under-resourced languages, including Malay. This research shows how it is possible to build an emotional speech acoustic model for Malay with minimal resources. To achieve this objective, two forms of initialization methods were considered: iterative training using the deterministic annealing expectation maximization algorithm and the isolated unit training. The seed model for the automatic segmentation is a neutral speech acoustic model, which was transformed to target emotion using two transformation techniques: model adaptation and context-dependent boundary refinement. Two forms of evaluation have been performed: an objective evaluation measuring the prosody error and a listening evaluation to measure the naturalness of the synthesized emotional speech.

Matched MeSH terms: Sound Spectrography
Highly sensitive Escherichia coli shear horizontal surface acoustic wave biosensor with silicon dioxide nanostructures

Ten ST, Hashim U, Gopinath SC, Liu WW, Foo KL, Sam ST, et al.

Biosens Bioelectron, 2017 Jul 15;93:146-154.
PMID: 27660016 DOI: 10.1016/j.bios.2016.09.035

Surface acoustic wave mediated transductions have been widely used in the sensors and actuators applications. In this study, a shear horizontal surface acoustic wave (SHSAW) was used for the detection of food pathogenic Escherichia coli O157:H7 (E.coli O157:H7), a dangerous strain among 225 E. coli unique serotypes. A few cells of this bacterium are able to cause young children to be most vulnerable to serious complications. Presence of higher than 1cfu E.coli O157:H7 in 25g of food has been considered as a dangerous level. The SHSAW biosensor was fabricated on 64° YX LiNbO3 substrate. Its sensitivity was enhanced by depositing 130.5nm thin layer of SiO2 nanostructures with particle size lesser than 70nm. The nanostructures act both as a waveguide as well as a physical surface modification of the sensor prior to biomolecular immobilization. A specific DNA sequence from E. coli O157:H7 having 22 mers as an amine-terminated probe ssDNA was immobilized on the thin film sensing area through chemical functionalization [(CHO-(CH2)3-CHO) and APTES; NH2-(CH2)3-Si(OC2H5)3]. The high-performance of sensor was shown with the specific oligonucleotide target and attained the sensitivity of 0.6439nM/0.1kHz and detection limit was down to 1.8femto-molar (1.8×10(-15)M). Further evidence was provided by specificity analysis using single mismatched and complementary oligonucleotide sequences.

Matched MeSH terms: Sound
Fulltext The heterospecific calling song can improve conspecific signal detection in a bushcricket species

Abdelatti ZAS, Hartbauer M

Hear Res, 2017 11;355:70-80.
PMID: 28974384 DOI: 10.1016/j.heares.2017.09.011

In forest clearings of the Malaysian rainforest, chirping and trilling Mecopoda species often live in sympatry. We investigated whether a phenomenon known as stochastic resonance (SR) improved the ability of individuals to detect a low-frequent signal component typical of chirps when members of the heterospecific trilling species were simultaneously active. This phenomenon may explain the fact that the chirping species upholds entrainment to the conspecific song in the presence of the trill. Therefore, we evaluated the response probability of an ascending auditory neuron (TN-1) in individuals of the chirping Mecopoda species to triple-pulsed 2, 8 and 20 kHz signals that were broadcast 1 dB below the hearing threshold while increasing the intensity of either white noise or a typical triller song. Our results demonstrate the existence of SR over a rather broad range of signal-to-noise ratios (SNRs) of input signals when periodic 2 kHz and 20 kHz signals were presented at the same time as white noise. Using the chirp-specific 2 kHz signal as a stimulus, the maximum TN-1 response probability frequently exceeded the 50% threshold if the trill was broadcast simultaneously. Playback of an 8 kHz signal, a common frequency band component of the trill, yielded a similar result. Nevertheless, using the trill as a masker, the signal-related TN-1 spiking probability was rather variable. The variability on an individual level resulted from correlations between the phase relationship of the signal and syllables of the trill. For the first time, these results demonstrate the existence of SR in acoustically-communicating insects and suggest that the calling song of heterospecifics may facilitate the detection of a subthreshold signal component in certain situations. The results of the simulation of sound propagation in a computer model suggest a wide range of sender-receiver distances in which the triller can help to improve the detection of subthreshold signals in the chirping species.

Matched MeSH terms: Sound Spectrography
Automatic Voice Pathology Detection With Running Speech by Using Estimation of Auditory Spectrum and Cepstral Coefficients Based on the All-Pole Model

Ali Z, Elamvazuthi I, Alsulaiman M, Muhammad G

J Voice, 2016 Nov;30(6):757.e7-757.e19.
PMID: 26522263 DOI: 10.1016/j.jvoice.2015.08.010

BACKGROUND AND OBJECTIVE: Automatic voice pathology detection using sustained vowels has been widely explored. Because of the stationary nature of the speech waveform, pathology detection with a sustained vowel is a comparatively easier task than that using a running speech. Some disorder detection systems with running speech have also been developed, although most of them are based on a voice activity detection (VAD), that is, itself a challenging task. Pathology detection with running speech needs more investigation, and systems with good accuracy (ACC) are required. Furthermore, pathology classification systems with running speech have not received any attention from the research community. In this article, automatic pathology detection and classification systems are developed using text-dependent running speech without adding a VAD module.
METHOD: A set of three psychophysics conditions of hearing (critical band spectral estimation, equal loudness hearing curve, and the intensity loudness power law of hearing) is used to estimate the auditory spectrum. The auditory spectrum and all-pole models of the auditory spectrums are computed and analyzed and used in a Gaussian mixture model for an automatic decision.
RESULTS: In the experiments using the Massachusetts Eye & Ear Infirmary database, an ACC of 99.56% is obtained for pathology detection, and an ACC of 93.33% is obtained for the pathology classification system. The results of the proposed systems outperform the existing running-speech-based systems.
DISCUSSION: The developed system can effectively be used in voice pathology detection and classification systems, and the proposed features can visually differentiate between normal and pathological samples.

Matched MeSH terms: Sound Spectrography

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