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1.
Comput Methods Programs Biomed ; 245: 108043, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38306944

RESUMEN

BACKGROUND AND OBJECTIVE: Conflict may happen when more than one classifier is used to perform prediction or classification. The recognition model error leads to conflicting evidence. These conflicts can cause decision errors in a baby cry recognition and further decrease its recognition accuracy. Thus, the objective of this study is to propose a method that can effectively minimize the conflict among deep learning models and improve the accuracy of baby cry recognition. METHODS: An improved Dempster-Shafer evidence theory (DST) based on Wasserstein distance and Deng entropy was proposed to reduce the conflicts among the results by combining the credibility degree between evidence and the uncertainty degree of evidence. To validate the effectiveness of the proposed method, examples were analyzed, and applied in a baby cry recognition. The Whale optimization algorithm-Variational mode decomposition (WOA-VMD) was used to optimally decompose the baby cry signals. The deep features of decomposed components were extracted using the VGG16 model. Long Short-Term Memory (LSTM) models were used to classify baby cry signals. An improved DST decision method was used to obtain the decision fusion. RESULTS: The proposed fusion method achieves an accuracy of 90.15% in classifying three types of baby cry. Improvement between 2.90% and 4.98% was obtained over the existing DST fusion methods. Recognition accuracy was improved by between 5.79% and 11.53% when compared to the latest methods used in baby cry recognition. CONCLUSION: The proposed method optimally decomposes baby cry signal, effectively reduces the conflict among the results of deep learning models and improves the accuracy of baby cry recognition.


Asunto(s)
Algoritmos , Ballenas , Lactante , Animales , Humanos , Incertidumbre , Entropía
2.
Phys Eng Sci Med ; 47(1): 61-71, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37843766

RESUMEN

Many studies have investigated the dielectric properties of human and animal tissues, particularly to differentiate between normal cells and tumors. However, these studies are invasive as tissue samples have to be excised to measure the properties. This study aims to investigate the dielectric properties of urine in relation to bladder cancer, which is safe and non-invasive to patients. 30 healthy subjects and 30 bladder cancer patients were recruited. Their urine samples were subjected to urinalysis and cytology assessment. A vector network analyzer was used to measure the dielectric constant (Ɛ') and loss factor (Ɛ″) at microwave frequencies of between 0.2 and 50 GHz at 25 °C, 30 °C and 37 °C. Significant differences in Ɛ' and Ɛ″ were observed between healthy subjects and patients, especially at frequencies of between 25 and 40 GHz at 25 °C. Bladder cancer patients had significant lower Ɛ' and higher Ɛ″ compared with healthy subjects. The Ɛ' was negatively correlated with urinary exfoliated urothelial cell number, and Ɛ″ was positively correlated. The study achieved a receiver operating characteristic area under curve (ROC-AUC) score of 0.69099 and an optimum accuracy of 75% with a sensitivity of 80% and a specificity of 70%. The number of exfoliated urothelial cell had significant effect on the dielectric properties, especially in bladder cancer patients. Urinary dielectric properties could potentially be used as a tool to detect bladder cancer.


Asunto(s)
Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/orina , Curva ROC , Urinálisis , Células Epiteliales/patología , Citodiagnóstico
3.
J Cancer ; 10(17): 4038-4044, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31417648

RESUMEN

Background and purpose: Bladder cancer is the most common malignant tumour in the urinary system, with a high incidence and recurrence rate. While the incidence of bladder cancer has been rising in recent years, the prevalence of bladder carcinoma is showing an increasing tendency in the younger age group. There are several methods to detect bladder cancer, but different methods have varying degrees of accuracy which intrinsically depends on the method's sensitivity and specificity. Our aim was to comprehensively summarize the current detection methods for bladder cancer based on the available literature, and at the same time, to find the best combination of different effective methods which can produce a high degree of accuracy in detecting the presence of cancerous cells in the bladder. Materials and Methods: We used key word retrieval method for searching related references in English that had been indexed in PubMed and Medline. Results and Discussion: This paper discussed the different detection methods and their sensitivities/specificities as well as the advantages and disadvantages. We summarized the best identified cancer cell detection methods with higher sensitivity/specificity. Conclusion: The results of this review can positively help to identify accurate methods for detecting bladder cancer and highlight areas to be further improved for future research work.

4.
J Int Adv Otol ; 15(1): 87-93, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30924771

RESUMEN

OBJECTIVES: This study uses a new approach for classifying the human ethnicity according to the auditory brain responses (electroencephalography [EEG] signals) with a high level of accuracy. Moreover, the study presents three different algorithms used to classify the human ethnicity using auditory brain responses. The algorithms were tested on Malays and Chinese as a case study. MATERIALS AND METHODS: The EEG signal was used as a brain response signal, which was evoked by two auditory stimuli (Tones and Consonant Vowels stimulus). The study was carried out on Malaysians (Malay and Chinese) with normal hearing and with hearing loss. A ranking process for the subjects' EEG data and the nonlinear features was used to obtain the maximum classification accuracy. RESULTS: The study formulated the classification of Normal Hearing Ethnicity Index and Sensorineural Hearing Loss Ethnicity Index. These indices classified the human ethnicity according to brain auditory responses by using numerical values of response signal features. Three classification algorithms were used to verify the human ethnicity. Support Vector Machine (SVM) classified the human ethnicity with an accuracy of 90% in the cases of normal hearing and sensorineural hearing loss (SNHL); the SVM classified with an accuracy of 84%. CONCLUSION: The classification indices categorized or separated the human ethnicity in both hearing cases of normal hearing and SNHL with high accuracy. The SVM classifier provided a good accuracy in the classification of the auditory brain responses. The proposed indices might constitute valuable tools for the classification of the brain responses according to the human ethnicity.


Asunto(s)
Electroencefalografía/instrumentación , Potenciales Evocados Auditivos/fisiología , Pérdida Auditiva Sensorineural/fisiopatología , Pérdida Auditiva/fisiopatología , Estimulación Acústica/métodos , Adulto , Algoritmos , Audiometría de Tonos Puros/métodos , China/epidemiología , China/etnología , Etnicidad/estadística & datos numéricos , Pérdida Auditiva Sensorineural/diagnóstico , Pérdida Auditiva Sensorineural/etnología , Humanos , Lenguaje , Malasia/etnología , Masculino , Persona de Mediana Edad , Ruido/efectos adversos , Percepción del Habla/fisiología , Máquina de Vectores de Soporte/normas
5.
Int J Health Sci (Qassim) ; 12(5): 25-34, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30202405

RESUMEN

OBJECTIVES: The hearing process in the brain is very complicated and hard to solve. However, an understanding of the hearing process is an essential issue and needed in many rehabilitation or treatment applications. This study investigates and compares the effects of simple and complex sounds on latency and amplitude of various event-related potential (ERP) components to male ethnic Malay adults. Comparisons were made with previous studies. MATERIALS AND METHODS: Simple and complex sounds were used (pure tones and the naturally produced Malay consonant-vowels [CVs]) to evoke the cortical auditory-evoked potential (CAEP) signals. Moreover, this study analyzed the influence of related CAEP components that are distinct to the selected population and determined which of the ERP components among (CAEP) components is most affected by the two distinct stimuli. Moreover, the study used classification algorithms to discover the ability of the brain in distinguishing CAEP evoked by stimuli contrasts. RESULTS: The results showed some resemblance between our results and ERP waveforms outlined in previous studies conducted on native speakers of English. On the other hand, it was also observed that the P1 and N2 had a significant effect in amplitude due to different stimulus. CONCLUSION: The results show high classification accuracy for the brain to distinguish auditory stimuli. Moreover, the results indicated some resemblance to previous studies conducted on native English speakers using similar tones and English CV stimuli. However, the amplitudes and latencies of the P1 were found to have a significant difference due to stimuli complexity.

6.
PLoS One ; 10(6): e0130011, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26066351

RESUMEN

This paper investigates the dielectric properties of urine in normal subjects and subjects with chronic kidney disease (CKD) at microwave frequency of between 0.2 GHz and 50 GHz. The measurements were conducted using an open-ended coaxial probe at room temperature (25°C), at 30°C and at human body temperature (37°C). There were statistically significant differences in the dielectric properties of the CKD subjects compared to those of the normal subjects. Statistically significant differences in dielectric properties were observed across the temperatures for normal subjects and CKD subjects. Pearson correlation test showed the significant correlation between proteinuria and dielectric properties. The experimental data closely matched the single-pole Debye model. The relaxation dispersion and relaxation time increased with the proteinuria level, while decreasing with the temperature. As for static conductivity, it increased with proteinuria level and temperature.


Asunto(s)
Conductividad Eléctrica , Proteinuria/orina , Insuficiencia Renal Crónica/orina , Urea/química , Adulto , Femenino , Humanos , Masculino
7.
Biomed Eng Online ; 13: 103, 2014 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-25060583

RESUMEN

The phonetic properties of six Malay vowels are investigated using magnetic resonance imaging (MRI) to visualize the vocal tract in order to obtain dynamic articulatory parameters during speech production. To resolve image blurring due to the tongue movement during the scanning process, a method based on active contour extraction is used to track tongue contours. The proposed method efficiently tracks tongue contours despite the partial blurring of MRI images. Consequently, the articulatory parameters that are effectively measured as tongue movement is observed, and the specific shape of the tongue and its position for all six uttered Malay vowels are determined.Speech rehabilitation procedure demands some kind of visual perceivable prototype of speech articulation. To investigate the validity of the measured articulatory parameters based on acoustic theory of speech production, an acoustic analysis based on the uttered vowels by subjects has been performed. As the acoustic speech and articulatory parameters of uttered speech were examined, a correlation between formant frequencies and articulatory parameters was observed. The experiments reported a positive correlation between the constriction location of the tongue body and the first formant frequency, as well as a negative correlation between the constriction location of the tongue tip and the second formant frequency. The results demonstrate that the proposed method is an effective tool for the dynamic study of speech production.


Asunto(s)
Acústica , Imagen por Resonancia Magnética , Habla/fisiología , Adulto , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Indonesia , Movimiento , Lengua/fisiología
8.
ScientificWorldJournal ; 2014: 534064, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25006595

RESUMEN

Automatic estimation of a speaker's age is a challenging research topic in the area of speech analysis. In this paper, a novel approach to estimate a speaker's age is presented. The method features a "divide and conquer" strategy wherein the speech data are divided into six groups based on the vowel classes. There are two reasons behind this strategy. First, reduction in the complicated distribution of the processing data improves the classifier's learning performance. Second, different vowel classes contain complementary information for age estimation. Mel-frequency cepstral coefficients are computed for each group and single layer feed-forward neural networks based on self-adaptive extreme learning machine are applied to the features to make a primary decision. Subsequently, fuzzy data fusion is employed to provide an overall decision by aggregating the classifier's outputs. The results are then compared with a number of state-of-the-art age estimation methods. Experiments conducted based on six age groups including children aged between 7 and 12 years revealed that fuzzy fusion of the classifier's outputs resulted in considerable improvement of up to 53.33% in age estimation accuracy. Moreover, the fuzzy fusion of decisions aggregated the complementary information of a speaker's age from various speech sources.


Asunto(s)
Técnicas de Apoyo para la Decisión , Lógica Difusa , Calidad de la Voz , Factores de Edad , Niño , Femenino , Humanos , Masculino , Voz/fisiología , Calidad de la Voz/fisiología
9.
J Voice ; 27(2): 201-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23473455

RESUMEN

Speech is one of the prevalent communication mediums for humans. Identifying the gender of a child speaker based on his/her speech is crucial in telecommunication and speech therapy. This article investigates the use of fundamental and formant frequencies from sustained vowel phonation to distinguish the gender of Malay children aged between 7 and 12 years. The Euclidean minimum distance and multilayer perceptron were used to classify the gender of 360 Malay children based on different combinations of fundamental and formant frequencies (F0, F1, F2, and F3). The Euclidean minimum distance with normalized frequency data achieved a classification accuracy of 79.44%, which was higher than that of the nonnormalized frequency data. Age-dependent modeling was used to improve the accuracy of gender classification. The Euclidean distance method obtained 84.17% based on the optimal classification accuracy for all age groups. The accuracy was further increased to 99.81% using multilayer perceptron based on mel-frequency cepstral coefficients.


Asunto(s)
Lenguaje Infantil , Fonación , Fonética , Acústica del Lenguaje , Calidad de la Voz , Factores de Edad , Algoritmos , Niño , Femenino , Humanos , Malasia , Masculino , Cadenas de Markov , Redes Neurales de la Computación , Factores Sexuales , Procesamiento de Señales Asistido por Computador , Medición de la Producción del Habla , Factores de Tiempo
10.
J Voice ; 26(4): 425-30, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22243972

RESUMEN

OBJECTIVE: The study is going to investigate the fundamental frequency (F(0)) and perturbation measures of sustained vowels in 360 native Malaysian Malay children aged between 7 and 12 years using acoustical analysis. METHODS: Praat software (Boersma and Weenink, University of Amsterdam, The Netherlands) was used to analyze the F(0) and perturbation measures of the sustained vowels. Statistical analyses were conducted to determine the significant differences in F(0) and perturbation measures across the vowels, sex, and age groups. RESULTS: The mean F(0) of Malaysian Malay male and female children were reported at 240±34.88 and 254.48±23.35Hz, respectively. The jitter (Jitt), relative average perturbation (RAP), five-point period perturbation quotient (PPQ5), shimmer (Shim), and 11-point amplitude perturbation quotient (APQ11) of Malaysian male children were reported at 0.43±0.26%, 0.25±0.16%, 0.26±0.15%, 2.48±1.61%, and 1.75±1.04%, respectively. As for female children, the Jitt, RAP, PPQ5, Shim, and APQ11 were reported at 0.42±0.22%, 0.25±0.14%, 0.25±0.13%, 2.47±1.53%, and 1.75±1.10%, respectively. CONCLUSIONS: No significant differences in F(0) were reported across the Malay vowels for both males and females. Malay females had significantly higher F(0) than that in Malay males at the age of 8, 10, and 12 years. Malaysian Malay children underwent the nonsystematic decrement in F(0) across the age groups. Significant differences in F(0) were found across the age groups. Significant differences in perturbation measures were observed across the vowels in certain age groups of Malay males and females. Generally, no significant differences in perturbation measures between the sex were observed in all the age groups and vowels. No significant differences in all the perturbation measures across the age groups were reported in both Malaysian Malay male and female children.


Asunto(s)
Acústica del Lenguaje , Factores de Edad , Niño , Femenino , Humanos , Lenguaje , Malasia , Masculino , Factores Sexuales
11.
J Voice ; 26(5): 664.e1-6, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22285457

RESUMEN

The formant frequencies of Malaysian Malay children have not been well studied. This article investigates the first four formant frequencies of sustained vowels in 360 Malay children aged between 7 and 12 years using acoustical analysis. Generally, Malay female children had higher formant frequencies than those of their male counterparts. However, no significant differences in all four formant frequencies were observed between the Malay male and female children in most of the vowels and age groups. Significant differences in all formant frequencies were found across the Malay vowels in both Malay male and female children for all age groups except for F4 in female children aged 12 years. Generally, the Malaysian Malay children showed a nonsystematic decrement in formant frequencies with age. Low levels of significant differences in formant frequencies were observed across the age groups in most of the vowels for F1, F3, and F4 in Malay male children and F1 and F4 in Malay female children.


Asunto(s)
Lenguaje Infantil , Fonética , Acústica del Lenguaje , Calidad de la Voz , Factores de Edad , Análisis de Varianza , Niño , Femenino , Humanos , Masculino , Factores Sexuales , Medición de la Producción del Habla , Factores de Tiempo
12.
J Voice ; 25(6): e311-7, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21376529

RESUMEN

The acoustic properties of vowel phonation vary across cultures. These specific characteristics, including vowel fundamental frequency (F(0)) and perturbation measures (Absolute Jitter [Jita], Jitter [Jitt], Relative Average Perturbation [RAP], five-point Period Perturbation Quotient [PPQ5], Absolute Shimmer [ShdB], Shimmer [Shim], and 11-point Amplitude Perturbation Quotient [APQ11]) are not well established for Malaysian Chinese adults. This article investigates the F(0) and perturbation measurements of sustained vowels in 60 normal Malaysian Chinese adults using acoustical analysis. Malaysian Chinese females had significantly higher F(0) than Malaysian males in all six vowels. However, there were no significant differences in F(0) across the vowels for each gender. Significant differences between vowels were observed for Jita, Jitt, PPQ5, ShdB, Shim, and APQ11 among Chinese males, whereas significant differences between vowels were observed for all the perturbation parameters among Chinese females. Chinese males had significantly higher Jita and APQ11 in the vowels than Chinese females, whereas no significant differences were observed between males and females for Jitt, RAP, PPQ5, and Shim. Cross-ethnic comparisons indicate that F(0) of vowel phonation varies within the Chinese ethnic group and across other ethnic groups. The perturbation measures cannot be simply compared, where the measures may vary significantly across different speech analysis softwares.


Asunto(s)
Fonación , Fonética , Acústica del Lenguaje , Pueblo Asiatico , Femenino , Humanos , Malasia , Masculino , Caracteres Sexuales , Adulto Joven
13.
J Voice ; 25(6): e305-9, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21429707

RESUMEN

The acoustic characteristics of sustained vowel have been widely investigated across various languages and ethnic groups. These acoustic measures, including fundamental frequency (F(0)), jitter (Jitt), relative average perturbation (RAP), five-point period perturbation quotient (PPQ5), shimmer (Shim), and 11-point amplitude perturbation quotient (APQ11) are not well established for Malaysian Malay young adults. This article studies the acoustic measures of Malaysian Malay adults using acoustical analysis. The study analyzed six sustained Malay vowels of 60 normal native Malaysian Malay adults with a mean of 21.19 years. The F(0) values of Malaysian Malay males and females were reported as 134.85±18.54 and 238.27±24.06Hz, respectively. Malaysian Malay females had significantly higher F(0) than that of males for all the vowels. However, no significant differences were observed between the genders for the perturbation measures in all the vowels, except RAP in /e/. No significant F(0) differences between the vowels were observed. Significant differences between the vowels were reported for all perturbation measures in Malaysian Malay males. As for Malaysian Malay females, significant differences between the vowels were reported for Shim and APQ11. Multiethnic comparisons indicate that F(0) varies between Malaysian Malay and other ethnic groups. However, the perturbation measures cannot be directly compared, where the measures vary significantly across different speech analysis softwares.


Asunto(s)
Fonética , Acústica del Lenguaje , Pueblo Asiatico , Femenino , Humanos , Malasia , Masculino , Caracteres Sexuales , Adulto Joven
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