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Vehicular traffic noise prediction and propagation modelling using neural networks and geospatial information system

Ahmed AA, Pradhan B

Environ Monit Assess, 2019 Feb 26;191(3):190.
PMID: 30809746 DOI: 10.1007/s10661-019-7333-3

This study proposes a neural network (NN) model to predict and simulate the propagation of vehicular traffic noise in a dense residential area at the New Klang Valley Expressway (NKVE) in Shah Alam, Malaysia. The proposed model comprises of two main simulation steps: that is, the prediction of vehicular traffic noise using NN and the simulation of the propagation of traffic noise emission using a mathematical model. First, the NN model was developed with the following selected noise predictors: the number of motorbikes, the sum of vehicles, car ratio, heavy vehicle ratio (e.g. truck, lorry and bus), highway density and a light detection and ranging (LiDAR)-derived digital surface model (DSM). Subsequently, NN and its hyperparameters were optimised by a systematic optimisation procedure based on a grid search approach. The noise propagation model was then developed in a geographic information system (GIS) using five variables, namely road geometry, barriers, distance, interaction of air particles and weather parameters. The noise measurement was conducted continuously at 15-min intervals and the data were analysed by taking the minimum, maximum and average values recorded during the day. The measurement was performed four times a day (i.e. morning, afternoon, evening, and midnight) over two days of the week (i.e. Sunday and Monday). An optimal radial basis function NN was used with 17 hidden layers. The learning rate and momentum values were 0.05 and 0.9, respectively. Finally, the accuracy of the proposed method achieved 78.4% with less than 4.02 dB (A) error in noise prediction. Overall, the proposed models were found to be promising tools for traffic noise assessment in dense urban areas.

Matched MeSH terms: Noise, Transportation
Fulltext Noise exposure and noise induced hearing loss among Kuala Lumpur traffic point duty personnel

Thomas N, Mariah AN, Fuad A, Kuljit S, Philip R

Med J Malaysia, 2007 Jun;62(2):152-5.
PMID: 18705450 MyJurnal

Thirty-two points in Kuala Lumpur were selected where traffic personnel were on duty. Sound level readings were taken three times a day. Generally, the traffic noise levels were between 75 dBA to 85 dBA. The maximum sound level recorded was 108.2 dBA. Noise emitted by traffic equipment and vehicles were up to 133 dBA. Results of audiometric tests revealed that out of 30 who were tested, 24 or 80% were positive for noise-induced hearing loss. A questionnaire survey revealed a lack of knowledge on occupational safety and personal protective equipment.

Matched MeSH terms: Hearing Loss, Noise-Induced/etiology*; Hearing Loss, Noise-Induced/prevention & control; Noise, Occupational/adverse effects*; Noise, Transportation/adverse effects*
Persistent noise after ceramic-on-ceramic total hip replacement due to bearing coupling size mismatch: A case report

Chan CK, Lee DH, Yoon TR, Park KS

J Orthop Sci, 2019 09;24(5):936-938.
PMID: 28390755 DOI: 10.1016/j.jos.2017.03.010
Matched MeSH terms: Noise*
Label-free optical spectroscopy for characterizing binding properties of highly sensitive nanocrystalline cellulose-graphene oxide based nanocomposite towards nickel ion

Daniyal WMEMM, Fen YW, Abdullah J, Sadrolhosseini AR, Saleviter S, Omar NAS

Spectrochim Acta A Mol Biomol Spectrosc, 2019 Apr 05;212:25-31.
PMID: 30594850 DOI: 10.1016/j.saa.2018.12.031

Surface plasmon resonance (SPR) is a label-free optical spectroscopy that is widely used for biomolecular interaction analysis. In this work, SPR was used to characterize the binding properties of highly sensitive nanocrystalline cellulose-graphene oxide based nanocomposite (CTA-NCC/GO) towards nickel ion. The formation of CTA-NCC/GO nanocomposite has been confirmed by FT-IR. The SPR analysis result shows that the CTA-NCC/GO has high binding affinity towards Ni2+ from 0.01 until 0.1 ppm with binding affinity constant of 1.620 × 103 M-1. The sensitivity for the CTA-NCC/GO calculated was 1.509° ppm-1. The full width at half maximum (FWHM), data accuracy (DA), and signal-to-noise ratio (SNR) have also been determined using the obtained SPR curve. For the FWHM, the value was 2.25° at 0.01 until 0.08 ppm and decreases to 2.12° at 0.1 until 10 ppm. The DA for the SPR curves is the highest at 0.01 until 0.08 ppm and lowest at 0.1 until 10 ppm. The SNR curves mirrors the curves of SPR angle shift where the SNR increases with the Ni2+ concentrations. For the selectivity test, the CTA-NCC/GO has the abilities to differentiate Ni2+ in the mixture of metal ions.

Matched MeSH terms: Signal-To-Noise Ratio
Fulltext Fuzzy logic based EKF for mobile robot navigation: An analysis of different fuzzy membership functions

Hamzah Ahmad, Nur Aqilah Othman

Pertanika Journal of Science & Technology, 2017;25(106):189-198.
MyJurnal

This paper deals with the analysis of different Fuzzy membership type performance for Extended Kalman Filter (EKF) based mobile robot navigation. EKF is known to be incompetent in non-Gaussian noise condition and therefore the technique alone is not sufficient to provide solution. Motivated by this shortcoming, a Fuzzy based EKF is proposed in this paper. Three membership types are considered which includes the triangular, trapezoidal and Gaussian membership types to determine the best estimation results for mobile robot and landmarks locations. Minimal rule design and configuration are also other aspects being considered for analysis purposes. The simulation results suggest that the Gaussian memberships surpassed other membership type in providing the best solution in mobile robot navigation.

Matched MeSH terms: Noise
Fulltext Environmental and occupational health impact of bauxite mining in Malaysia: a review

Lee, K.Y., Ho, L.Y., Tan, K.H., Tham, Y.Y., Ling, S.P., Qureshi, A.M., et al.

International Medical Journal Malaysia, 2017;16(2):137-150.
MyJurnal

In the perspective of recent bauxite mining in Malaysia, this review aims to identify the potential
environmental and health impacts on miners and surrounding communities. The environmental issues of
bauxite mining include, air, water and soil pollution due to bauxite dust; leaching of bauxite into water
sources resulting in reduced soil fertility as well as affecting agricultural food products and aquatic life.
Bauxite occupational exposure affects the health of miners, and has negative consequences on the health of
surrounding communities, such as increased respiratory symptoms, contamination of drinking water, other
potential health risks from ingestion of bauxite and heavy metals, including noise-induced hearing loss and
mental stress. This review discusses the processes of bauxite mining, its constituents and residual trace
elements, and their impact on the environment and health of exposed workers and communities. It also
explores the Malaysian legal requirements and standards of occupational exposure to bauxite.

Matched MeSH terms: Hearing Loss, Noise-Induced
Fulltext Improved architecture of speaker recognition based on wavelet transform and Mel Frequency Cepstral Coefficient (MFCC)

Nor Ashikin Rahman, Noor Azilah Muda, Norashikin Ahmad

Pertanika Journal of Science & Technology, 2017;25(106):1-10.
MyJurnal

Combining Mel Frequency Cepstral Coefficient with wavelet transform for feature extraction is not new. This paper proposes a new architecture to help in increasing the accuracy of speaker recognition compared with conventional architecture. In conventional speaker model, the voice will undergo noise elimination first before feature extraction. The proposed architecture however, will extract the features and eliminate noise simultaneously. The MFCC is used to extract the voice features while wavelet de-noising technique is used to eliminate the noise contained in the speech signals. Thus, the new architecture achieves two outcomes in one single process: ex-tracting voice feature and elimination of noise.

Matched MeSH terms: Noise
Fulltext New regression model for predicting hand-arm vibration (HAV) of Malaysian Army (MA) three-tonne truck steering wheels

Aziz SA, Nuawi MZ, Nor MJ

J Occup Health, 2015;57(6):513-20.
PMID: 26269278 DOI: 10.1539/joh.14-0206-OA

OBJECTIVE: The objective of this study was to present a new method for determination of hand-arm vibration (HAV) in Malaysian Army (MA) three-tonne truck steering wheels based on changes in vehicle speed using regression model and the statistical analysis method known as Integrated Kurtosis-Based Algorithm for Z-Notch Filter Technique Vibro (I-kaz Vibro).
METHODOLOGY: The test was conducted for two different road conditions, tarmac and dirt roads. HAV exposure was measured using a Brüel & Kjær Type 3649 vibration analyzer, which is capable of recording HAV exposures from steering wheels. The data was analyzed using I-kaz Vibro to determine the HAV values in relation to varying speeds of a truck and to determine the degree of data scattering for HAV data signals.
RESULTS: Based on the results obtained, HAV experienced by drivers can be determined using the daily vibration exposure A(8), I-kaz Vibro coefficient (Ƶ(v)(∞)), and the I-kaz Vibro display. The I-kaz Vibro displays also showed greater scatterings, indicating that the values of Ƶ(v)(∞) and A(8) were increasing. Prediction of HAV exposure was done using the developed regression model and graphical representations of Ƶ(v)(∞). The results of the regression model showed that Ƶ(v)(∞) increased when the vehicle speed and HAV exposure increased.
DISCUSSION: For model validation, predicted and measured noise exposures were compared, and high coefficient of correlation (R(2)) values were obtained, indicating that good agreement was obtained between them. By using the developed regression model, we can easily predict HAV exposure from steering wheels for HAV exposure monitoring.

Matched MeSH terms: Noise, Occupational/statistics & numerical data
Fulltext Robust digit recognition with dynamic time warping and recursive least squares

Al-Haddad, S.A.R., Samad, S.A., Hussain, A., Ishak, K.A., Noor, A.O.A.

ASM Science Journal, 2008;2(1):75-81.
MyJurnal

Robustness is a key issue in speech recognition. A speech recognition algorithm for Malay digits from zero to nine and an algorithm for noise cancellation by using recursive least squares (RLS) is proposed in this article. This system consisted of speech processing inclusive of digit margin and recognition using zero crossing and energy calculations. Mel-frequency cepstral coefficient vectors were used to provide an estimate of the vocal tract filter. Meanwhile dynamic time warping was used to detect the nearest recorded voice with appropriate global constraint. The global constraint was used to set a valid search region because the variation of the speech rate of the speaker was considered to be limited in a reasonable range which meant that it could prune the unreasonable search space. The algorithm was tested on speech samples that were recorded as part of a Malay corpus. The results showed that the algorithm managed to recognize almost 80.5% of the Malay digits for all recorded words. The addition of a RLS noise canceller in the preprocessing stage increased the accuracy to 94.1%.

Matched MeSH terms: Noise
Fulltext A study of occupational noise exposure among public transportation workers in Malaysia

Siti Norhafiza Abd Razak, Nurul Hazwani Mohd Yusoff, Farah Hana Mukhtar, Norsehah Abdul Karim, Noor Hasyimah Abu Rahim

Journal of Occupational Safety and Health, 2015;12(1):69-72.
MyJurnal

Working for a minimum of 8 hours, 6 days a week might have exposed the workers of public transportation to
high noise risks. However, occupational exposures in their workplace have not been adequately characterized and
identified. Assessment of occupational noise exposure among workers at five public transportation stations was made
using Sound Level Meter and through questionnaire survey. The data obtained was combined to estimate the work
shift exposure level and health impacts to the workers by using statistical analysis. The respondents participated in the
survey to identify the symptoms of noise-induced hearing loss and other health-related problems. Results of the study
indicated that occupational noise exposure among workers for Mean Continuous Equivalent Level, Leq= 76.17 dB(A)
presents small risks of developing a hearing disability. Some of the workers show symptoms of noise-induced hearing
loss and are annoyed by the sources of noise present at the public transportation.

Matched MeSH terms: Hearing Loss, Noise-Induced; Noise, Occupational
Effect of noise and pesticide exposures among foggers in Selangor health district offices

Anita, AR., Noor Hassim, I.

Journal of Occupational Safety and Health, 2013;10(1):27-37.
MyJurnal

Fogging activity has become one of the important methods in tackling dengue outbreaks nowadays. Despite this, it is an occupation that has known hazards namely noise and pesticides which can affect the body organs. Based on this knowledge, a cross sectional study was conducted to determine the association between hearing impairment and serum cholinesterase level among foggers from five randomly selected Health District Offices in Selangor. A total of 200 workers comprising of 100 workers exposed to fogging activity and another 100 workers not exposed were randomly selected for this study. Data was obtained through self administered questionnaire, audiometric testing and serum cholinesterase level measurement. The overall prevalence of hearing impairment was 16% with foggers having significant higher prevalence (24%) compared to the non foggers (8%) (χ2=9.52, p=0.002). Measurement of serum cholinesterase showed that exposed workers had lower level compared to the non exposed group. Similarly, those who have hearing impairment had also lower serum cholinesterase level although it was not statistically different. Among all studied factors, age and duration of exposure to fogging activities were statistically different with hearing impairment (p

Matched MeSH terms: Noise
A study on compliance to hearing conservation programme among industries in Negeri Sembilan, Malaysia

Nor Saleha IT, Noor Hassim I

Ind Health, 2006 Oct;44(4):584-91.
PMID: 17085919

Noise is one of the hazards faced by workers. A cross-sectional study was conducted among industries in Negeri Sembilan with the objective to assess their compliance to Hearing Conservation Programme (HCP). The other objectives of this study were to determine the factors influencing it and to show the industries' compliance to each element of the programme. It was also to identify the association between compliance to HCP and the prevalence of hearing impairment and standard threshold shift. Data for this study were collected using questionnaires sent by mail and also the results of the latest audiometric tests. A total of 167 industries were analysed for this study. It was found that 41.3% of these industries fully complied to the programme. It was also found that the industries preferred to provide hearing protection device (92.8%) and least complied to noise control (61.1%). There were significant associations (p<0.05) between compliance and number of employees, status of ownership and the presence of officer in charge of hearing conservation programme. Having at least 150 employees actually raised the compliance to HCP in two folds (beta = 0.717, OR = 2.048, C.I 95% = 1.063 to 3.944). The prevalences of hearing impairment and standard threshold shift were 23.9% and 5.2% respectively. There was no significant association between the prevalence for hearing impairment and compliance to HCP. The prevalence for standard threshold shift was inversely related to compliance. This study showed that compliance percentage need to be improved as an effort to prevent the hearing problems among workers exposed to noise.

Matched MeSH terms: Hearing Loss, Noise-Induced/etiology; Hearing Loss, Noise-Induced/epidemiology; Hearing Loss, Noise-Induced/prevention & control*; Noise, Occupational/adverse effects*
Effects of noise in the workplace

Noor Hassim I

Family Physician, 1991;3:14-16.

Matched MeSH terms: Noise
Pure-tone audiometry and auditory brainstem responses in noise-induced deafness

Noorhassim I, Kaga K, Nishimura K

Am J Otolaryngol, 1996 1 1;17(1):31-5.
PMID: 8801813

PURPOSE: The objective of this study is to find the relationship between pure-tone audiometry results and the auditory brainstem response wave abnormalities.
SUBJECTS AND METHODS: The pure-tone audiometry (PTA) and auditory brainstem responses (ABRs) from 22 patients (44 ears) with diagnosed noise-induced permanent hearing loss were studied. Three indices of PTA were average thresholds of 0.5 kHz/, /1 kHz, and 2 kHz (PTA1); 2 kHz and 4 kHz (PTA2); and 4 kHz (PTA3) were subdivided into 3 thresholds of hearing. Their relationships with ABR results were analysed. The patterns of PTA from various groups of ABR wave patterns were studied.
RESULTS: In this study, the abnormal ABR wave patterns were detected in 72.7% of the ears. The ears with prolonged ABR wave latency, absent early waves, prolong interpeak wave I-V latency was 20.5%, 18.2%, and 21.1%, respectively. Normal ABRs were recorded in 27.3% of the ears despite marked thresholds elevation of the PTA at high frequencies. Other relationships between PTA results and ABR wave results were discussed.
CONCLUSION: There were relationships between severity of noise-induced hearing loss indicated by PTA and the patterns of ABR wave abnormalities among workers with noise-induced permanent hearing loss.

Matched MeSH terms: Hearing Loss, Noise-Induced/diagnosis*
On optimizing the blocking step of indirect enzyme-linked immunosorbent assay for Epstein-Barr virus serology

Lim CS, Krishnan G, Sam CK, Ng CC

Clin Chim Acta, 2013 Jan 16;415:158-61.
PMID: 23043757 DOI: 10.1016/j.cca.2012.08.031

Because blocking agent occupies most binding surface of a solid phase, its ability to prevent nonspecific binding determines the signal-to-noise ratio (SNR) and reliability of an enzyme-linked immunosorbent assay (ELISA).

Matched MeSH terms: Signal-To-Noise Ratio
Effect of acute noise stress on acetylcholinesterase activity in discrete areas of rat brain

Sembulingam K, Sembulingam P, Namasivayam A

Indian J Med Sci, 2003 Nov;57(11):487-92.
PMID: 14646156

Effect of various stressor agents on the adrenergic system in brain had been studied extensively. However, reports on the effect of stress on various parameters of central cholinergic system are scanty. And very little is known about the effect of noise stress on the cholinergic system in brain. Hence, it was decided to elucidate the effect of acute noise stress on the activity of the enzyme acetylcholinesterase in discrete areas of brain in albino rats. Male albino rats of Wistar strain were subjected to acute noise stress for 30 minutes. The noise of pure sine wave tone was produced by using a function generator and was amplified. The frequency of noise generated was 1 kHz and the intensity was set at 100 dB. The total acetylcholinesterase activity was determined in the tissues of cerebral cortex, corpus striatum, hypothalamus and hippocampus of brain in these rats. The enzyme activity was estimated by colorimetric method using acetylthiocholine iodide as the substrate. The values were compared with the enzyme activity in the control rats. The activity of the enzyme increased significantly in all the four regions of the brain in rats after exposure to noise stress for 30 minutes. The results of the study indicate that the exposure to acute noise stress could modulate the cholinergic system in these areas of brain in rat.

Matched MeSH terms: Noise/adverse effects*
Fulltext An efficient post-processing adaptive filtering technique to rectifying the flickering effects

Gandam A, Sidhu JS, Verma S, Jhanjhi NZ, Nayyar A, Abouhawwash M, et al.

PLoS One, 2021;16(5):e0250959.
PMID: 33970949 DOI: 10.1371/journal.pone.0250959

Compression at a very low bit rate(≤0.5bpp) causes degradation in video frames with standard decoding algorithms like H.261, H.262, H.264, and MPEG-1 and MPEG-4, which itself produces lots of artifacts. This paper focuses on an efficient pre-and post-processing technique (PP-AFT) to address and rectify the problems of quantization error, ringing, blocking artifact, and flickering effect, which significantly degrade the visual quality of video frames. The PP-AFT method differentiates the blocked images or frames using activity function into different regions and developed adaptive filters as per the classified region. The designed process also introduces an adaptive flicker extraction and removal method and a 2-D filter to remove ringing effects in edge regions. The PP-AFT technique is implemented on various videos, and results are compared with different existing techniques using performance metrics like PSNR-B, MSSIM, and GBIM. Simulation results show significant improvement in the subjective quality of different video frames. The proposed method outperforms state-of-the-art de-blocking methods in terms of PSNR-B with average value lying between (0.7-1.9db) while (35.83-47.7%) reduced average GBIM keeping MSSIM values very close to the original sequence statistically 0.978.

Matched MeSH terms: Signal-To-Noise Ratio*
Fulltext Knowledge, attitude and practice of sawmill workers towards noise-induced hearing loss in kota bharu, kelantan

Rus RM, Daud A, Musa KI, Naing L

Malays J Med Sci, 2008 Oct;15(4):28-34.
PMID: 22589635

The purpose of this study was to determine the sawmill workers' knowledge, attitude and practice (KAP) in relation to noise-induced hearing loss (NIHL). A cross-sectional study was conducted involving 83 workers from 3 factories in Kota Bharu, Kelantan. Questionnaires were distributed to obtain the socio-demography, knowledge, attitude and practice level in relation to noise-induced hearing loss (NIHL). The weak areas identified in the knowledge section were treatment aspects (15.5%), signs and symptoms of NIHL (20.2%) and risk factors (31%). As for attitude; the prevention aspects were the lowest (25.3%), followed by risk taking attitude (26.2%), and causes of hearing loss (42.1%). Overall, the practice was not encouraging at all. It is important to have an education program to raise workers' awareness and to improve their attitude and practices towards noise-induced hearing loss.

Matched MeSH terms: Hearing Loss, Noise-Induced
Fulltext Linguistic context effects in the speech perfection of Malay-speaking normal hearing young adults

Cila Umat, Nahazatul Islia Jamari

Jurnal Sains Kesihatan Malaysia, 2006;4(1):9-20.
MyJurnal

The study examined the use of linguistic contextual cues among native, Malay-speaking normal hearing young adults. Ten undergraduate students of Universiti Kebangsaan Malaysia participated in the study. All subjects had normal hearing with the average hearing threshold levels for the overall left and the right ears of 7.8 dB (SD 4.1). The Malay Hearing in Noise Test (MyHINT) materials were employed and presented to the subjects at an approximately 65 dBA presentation level. Testing was conducted in a sound field in three different listening conditions: in quiet, in noise with +5 dB signal-to-noise ratio (SNR) and 0 dB SNR. In every test condition, three lists of MyHINT were administered to each subject. The magnitude of context effects was measured using the j factor, which was derived from measurements of recognition probabilities for whole sentences (13,) and the constituent words in the sentences (PP) in which j = log P./ log P P. Results showed that all subjects scored 100% identification of words in sentences and whole sentences in quiet listening condition, while subjects' performances in 0 dB SNR were significantly poorer than that in quiet and in +5 dB SNR (p < 0.001). The j-values were significantly correlated with the probability of recognizing words in the sentences (r = 0.515, p = 0.029) in which lower j values were associated with lower P ps. Subjects were not significantly different from each other in their use of contextual cues in adverse listening conditions [F(9, 7) = 1.34, p = 0.359]. Using the linear regression function for j on word recognition probabilities, the predicted P. were calculated. It was found that the predicted and measured probabilities of recognizing whole sentences were highly correlated: r = 0.973, p < 0.001. The results suggested that linguistic contextual information become increasingly important for recognition of sentences by normal hearing young adult listeners as SNR deteriorates.

Matched MeSH terms: Noise; Signal-To-Noise Ratio
Fulltext Noise exposure and hearing threshold profile among Zumba fitness regulars in Kuantan, Pahang, Malaysia

Ailin Razali, M. S. Othman, M. S. Rahman, N. F.I. Misaridin

IIUM Medical Journal Malaysia, 2020;19(2):67-73.
MyJurnal

Recreational noise exposure has become a major threat to the hearing system, and this
includes exposure to loud noise during group exercises such as Zumba Fitness, where loud music plays an
important role. This study aimed to assess the noise exposure and hearing threshold profile among Zumba
Fitness regulars in Kuantan, Malaysia. MATERIALS AND METHODS: Noise exposure and hearing profile
threshold were measured during Zumba Fitness sessions at a fitness studio in Kuantan, Malaysia from 24th
June 2014 to 12th August 2014. Noise exposure was measured using a noise dosimeter for one hour of Zumba
Fitness session with a total of nine sessions run by three different instructors while sound level pressure was
taken using a sound level meter during ambient, peak session and during cooling down. Thirty participants
answered questionnaires and underwent pure tone diagnostic audiometry test at a local clinic for hearing
threshold documentation. RESULTS: Some areas of the hall posed higher risks of causing noise-induced
hearing loss especially near the amplifiers. There were periods when the hearing level exceeded 115 dBA.
Early abnormal pattern could be observed in the hearing profiles of some of the participants to suggest
preliminary hearing problems. CONCLUSION: Zumba Fitness regulars have a risk of developing noise-induced
hearing loss and preventive steps should be properly addressed as NIHL is permanent and irreversible.

Matched MeSH terms: Noise

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