A Study on the Sound Quality Evaluation Model of the Air Cleaner

2007 ◽  
Author(s):  
Jeong-Guon Ih ◽  
Su-Won Jang ◽  
Cheol-Ho Jeong ◽  
Youn-Young Jeung ◽  
Kye-Sup Jun
Keyword(s):  
High Frequency ◽  
Quality Evaluation ◽  
Principal Component ◽  
Sound Quality ◽  
Differential Method ◽  
Subjective Feeling ◽  
Subjective Data ◽  
Frequency Bands ◽  
Air Cleaner ◽  
Air Cleaners

In operating the air cleaner for a long time, people in a quiet enclosed space expect calm sound at low operational levels for a routine cleaning of air; in contrast, a powerful, yet not-annoying, sound is expected at high operational levels for an immediate cleaning of pollutants. In this context, it is important to evaluate and design the air cleaner noise to satisfy such contradictory expectation from the customers. In this study, a model for evaluating the air cleaner sound quality was developed based on the objective and subjective analyses. Sound signals from various air cleaners were recorded and they were edited by increasing or decreasing the loudness at three wide specific-loudness bands: 20–400 Hz (0–3.8 Bark), 400–1250 Hz (3.8–10 Bark), 1.25k–12.5k Hz bands (10–22.8 Bark). Subjective tests using the edited sounds were conducted by the semantic differential method (SDM) and the method of successive intervals (MSI). SDM test for 7 adjective pairs was conducted to find the relation between subjective feeling and frequency bands. Two major feelings, performance and annoyance, were factored out from the principal component analysis. We found that the performance feeling was related to both low and high frequency bands; whereas the annoyance feeling was related to high frequency bands. MSI test using the 7 scales was conducted to derive the sound quality index to express the severity of each perceptive descriptor. Annoyance and performance indices of air cleaners were modeled from the subjective responses of the juries and the measured sound quality metrics: loudness, sharpness, roughness, and fluctuation strength. Multiple regression method was employed to generate sound quality evaluation models. Using the developed indices, sound quality of the measured data were evaluated and compared with the subjective data. The difference between predicted and tested scores was less than 0.5 point.

A Study on the Sound Quality Evaluation Model of Mechanical Air-Cleaners

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Jeong-Guon Ih ◽  
Su-Won Jang ◽  
Cheol-Ho Jeong ◽  
Youn-Young Jeung
Keyword(s):  
High Frequency ◽  
Quality Evaluation ◽  
Principal Component ◽  
Sound Quality ◽  
Subjective Feeling ◽  
Subjective Data ◽  
Frequency Bands ◽  
Air Cleaner ◽  
Air Cleaners

In operating the air-cleaner for a long time, people in a quiet enclosed space expect low sound at low operational levels for a routine cleaning of air. However, in the condition of high operational levels of the cleaner, a powerful yet nonannoying sound is desired, which is connected to a feeling of an immediate cleaning of pollutants. In this context, it is important to evaluate and design the air-cleaner noise to satisfy such contradictory expectations from the customers. In this study, a model for evaluating the sound quality of air-cleaners of mechanical type was developed based on objective and subjective analyses. Sound signals from various air-cleaners were recorded and they were edited by increasing or decreasing the loudness at three wide specific-loudness bands: 20–400 Hz (0–3.8 barks), 400–1250 Hz (3.8–10 barks), and 1.25–12.5 kHz bands (10–22.8 barks). Subjective tests using the edited sounds were conducted by the semantic differential method (SDM) and the method of successive intervals (MSI). SDM tests for seven adjective pairs were conducted to find the relation between subjective feeling and frequency bands. Two major feelings, performance and annoyance, were factored out from the principal component analysis. We found that the performance feeling was related to both low and high frequency bands, whereas the annoyance feeling was related to high frequency bands. MSI tests using the seven scales were conducted to derive the sound quality index to express the severity of each perceptive descriptor. Annoyance and performance indices of air-cleaners were modeled from the subjective responses of the juries and the measured sound quality metrics: loudness, sharpness, roughness, and fluctuation strength. The multiple regression method was employed to generate sound quality evaluation models. Using the developed indices, sound quality of the measured data was evaluated and compared with the subjective data. The difference between predicted and tested scores was less than 0.5 points.

A Comparison of Psychoacoustical Evaluation Methods for Vehicle Engine Noises Based on Wavelet Shrinkage Denoising Technique

2011 ◽  
Vol 219-220 ◽  
pp. 93-97 ◽  
Author(s):  
Yan Song Wang ◽  
Yue Yan ◽  
Zhi Qiu ◽  
Jin Zhang
Keyword(s):  
Sound Pressure Level ◽  
Sound Pressure ◽  
Quality Evaluation ◽  
Sound Quality ◽  
Pressure Level ◽  
Signal Denoising ◽  
Subjective Feeling ◽  
Wavelet Shrinkage ◽  
Vehicle Engine ◽  
Shrinkage Method

Based on the measured and denoised vehicle engine noises, the sound quality evaluation (SQE) techniques in common use for A-weighting sound pressure level (SPL) and psychoacoustical parameters, such as loudness, sharpness and roughness, are performed and compared in this paper. The wavelet threshold shrinkage method is adopted for sound signal denoising. The comparisons suggest that the A-weighting SPL is not sufficient and can only be used as a reference in vehicle SQE, the psychoacoustical parameters can provide a complete description and more exactly reflect to the subjective feeling of vehicle noises, should be considered in vehicle designs.

scholarly journals Changes of the Korean Consonant-Vowel Syllabic Recognition Scores According to the Compression Threshold Control of Multi-Channel Hearing Aid

2020 ◽  
Vol 16 (4) ◽  
pp. 321-328
Author(s):  
Dajung Yun ◽  
Kyoungwon Lee
Keyword(s):  
Hearing Aids ◽  
High Frequency ◽  
Pure Tone ◽  
Sound Quality ◽  
Conversational Speech ◽  
Signal To Noise ◽  
Threshold Control ◽  
Frequency Bands ◽  
Pure Tone Average ◽  
The Subject

Purpose: While adjusting the compression threshold (CT) of low and high frequency bands of multi-channel hearing aids in noise, we tried to evaluate any changes in Korean consonant-vowel (CV) syllabic recognition scores, sound quality, and loudness of noise with white noise.Methods: A total of twenty one subjects with hearing loss (mean age of 66.2 years) participated voluntarily. Their pure-tone average was 46.0 dB HL and the word recognition score was 72.1%. The CTs of low/high frequency bands were adjusted to 50/50 dB SPL, 50/65 dB SPL, 65/50 dB SPL and 60/65 dB SPL in multi-channel hearing aids. While presenting white noise to the non-test ear, Korean CV syllables were presented to the test ear to evaluate the recognition scores, clarity of conversational speech, and loudness of noise. The intensity of CV syllables presented to the subject was 50 dB HL, and the signal-to-noise ratios (SNRs) were 5 dB and 10 dB.Results: First, when the CT of low/high frequency bands was adjusted to 50/50 dB SPL, the CV syllabic recognition scores were higher compared to 65/50 dB SPL. Second, in the noise environment, the clarity of conversational speech, and loudness of the noise did not have any difference regardless of levels of CT.Conclusion: Based on current findings, the frequency bands setting of CT in the multi-channel hearing aids might provide changes to recognize Korean speech sounds, which may affect the adjustment of frequency band CT from multichannel hearing aids in the future.

scholarly journals Perceived Sound Quality Dimensions Influencing Frequency-Gain Shaping Preferences for Hearing Aid-Amplified Speech and Music

2021 ◽  
Vol 25 ◽  
pp. 233121652198990 ◽  
Author(s):  
Jonathan M. Vaisberg ◽  
Steve Beaulac ◽  
Danielle Glista ◽  
Ewan A. Macpherson ◽  
Susan D. Scollie
Keyword(s):  
Hearing Aids ◽  
High Frequency ◽  
Speech Intelligibility ◽  
Classical Music ◽  
Paired Comparison ◽  
Hearing Aid ◽  
Low Frequency ◽  
Sound Quality ◽  
Pop Music ◽  
Frequency Bands

Hearing aids are typically fitted using speech-based prescriptive formulae to make speech more intelligible. Individual preferences may vary from these prescriptions and may also vary with signal type. It is important to consider what motivates listener preferences and how those preferences can inform hearing aid processing so that assistive listening devices can best be tailored for hearing aid users. Therefore, this study explored preferred frequency-gain shaping relative to prescribed gain for speech and music samples. Preferred gain was determined for 22 listeners with mild sloping to moderately severe hearing loss relative to individually prescribed amplification while listening to samples of male speech, female speech, pop music, and classical music across low-, mid-, and high-frequency bands. Samples were amplified using a fast-acting compression hearing aid simulator. Preferences were determined using an adaptive paired comparison procedure. Listeners then rated speech and music samples processed using prescribed and preferred shaping across different sound quality descriptors. On average, low-frequency gain was significantly increased relative to the prescription for all stimuli and most substantially for pop and classical music. High-frequency gain was decreased significantly for pop music and male speech. Gain adjustments, particularly in the mid- and high-frequency bands, varied considerably between listeners. Music preferences were driven by changes in perceived fullness and sharpness, whereas speech preferences were driven by changes in perceived intelligibility and loudness. The results generally support the use of prescribed amplification to optimize speech intelligibility and alternative amplification for music listening for most listeners.

Model for Estimating Effects of Human Body Shadowing in High Frequency Bands

2015 ◽  
Vol E98.B (5) ◽  
pp. 773-782 ◽  
Author(s):  
Ngochao TRAN ◽  
Tetsuro IMAI ◽  
Yukihiko OKUMURA
Keyword(s):  
Human Body ◽  
High Frequency ◽  
Frequency Bands

Terahertz Radiators Based on Si~3C-SiC MQW IMPATT Diodes

2020 ◽  
Vol 10 (4) ◽  
pp. 501-506
Author(s):  
Monisha Ghosh ◽  
Arindam Biswas ◽  
Aritra Acharyya
Keyword(s):  
High Frequency ◽  
Multiple Quantum Well ◽  
Multiple Quantum ◽  
Noise Performance ◽  
Rf Power ◽  
Drift Diffusion ◽  
Frequency Bands ◽  
Atmospheric Window ◽  
Lower Noise ◽  
Impatt Diodes

Aims:: The potentiality of Multiple Quantum Well (MQW) Impacts Avalanche Transit Time (IMPATT) diodes based on Si~3C-SiC heterostructures as possible terahertz radiators have been explored in this paper. Objective:: The static, high frequency and noise performance of MQW devices operating at 94, 140, and 220 GHz atmospheric window frequencies, as well as 0.30 and 0.50 THz frequency bands, have been studied in this paper. Methods: The simulation methods based on a Self-Consistent Quantum Drift-Diffusion (SCQDD) model developed by the authors have been used for the above-mentioned studies. Results: Thus the noise performance of MQW DDRs will be obviously better as compared to the flat Si DDRs operating at different mm-wave and THz frequencies. Conclusion:: Simulation results show that Si~3C-SiC MQW IMPATT sources are capable of providing considerably higher RF power output with the significantly lower noise level at both millimeter-wave (mm-wave) and terahertz (THz) frequency bands as compared to conventional flat Si IMPATT sources.

Quality evaluation of tugaksheeree samples by ATR-FTIR spectroscopy using multicomponent analysis

2020 ◽  
Vol 10 ◽  
Author(s):  
Nikunj D. Patel ◽  
Niranjan S. Kanaki
Keyword(s):  
Principal Component Analysis ◽  
Cluster Analysis ◽  
Quality Evaluation ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Attenuated Total Reflectance ◽  
Chemometric Methods ◽  
Total Reflectance ◽  
Fingerprint Region ◽  
Ftir Technique

Background: Numerous Ayurvedic formulations contains tugaksheeree as key ingredient. Tugaksheereeis the starch gained from the rhizomes of two plants, Curcuma angustifoliaRoxb. (Zingiberaceae) and Marantaarundinacea (MA) Linn. (Marantaceae). Objective: The primary concerns in quality assessment of Tugaksheeree occur due to adulteration or substitution. Method: In current study, Fourier transform infrared (FTIR) technique with attenuated total reflectance (ATR) facility was used to evaluate tugaksheeree samples. Total 10 different samples were studied and transmittance mode was kept to record the spectra devoid of pellets of KBR. Further treatment was given with multi component tools by considering fingerprint region of the spectra. Multivariate analysis was performed by various chemometric methods. Result: Multi component methods like Principal Component Analysis (PCA), and Hierarchical Cluster Analysis (HCA)were used to discriminate the tugaksheeree samples using Minitab software. Conclusion: This method can be used as a tool to differentiate samples of tugaksheeree from its adulterants and substitutes.

Polarization analysis of high-frequency, three-component seismic data

1991 ◽  
Vol 81 (2) ◽  
pp. 622-642
Author(s):  
K. Bataille ◽  
J. M. Chiu
Keyword(s):  
High Frequency ◽  
Time Windows ◽  
Random Noise ◽  
Polarization State ◽  
Principal Component ◽  
Small Time ◽  
Body Waves ◽  
Local Data ◽  
Principal Component Approach ◽  
Component Approach

Abstract We present a method to determine the polarization of body waves from three-component, high-frequency data and examples of its application. The method is based on the principal component approach. One advantage of this approach is that the polarization state can be determined for small time windows compared with the predominant period of the wave. This is particularly useful for identifying converted waves within the crust. The stability of the result is analyzed with synthetic cases by adding simultaneous arrivals from waves and random noise. The method works well with both synthetic and local data in the detection of the polarization of the wave by separating arrivals from different directions. From the local data, some seismic phases related to crustal conversions are observed that require strong lateral variations.

Piper nigrum Oil – Determination of Selected Terpenes for Quality Evaluation

Planta Medica ◽  
2018 ◽  
Vol 85 (03) ◽  
pp. 185-194 ◽  
Author(s):  
Mei Wang ◽  
Amar Chittiboyina ◽  
Jon Parcher ◽  
Zulfiqar Ali ◽  
Paul Ford ◽  
...  
Keyword(s):  
Quality Evaluation ◽  
Geographical Location ◽  
Chemical Characterization ◽  
Principal Component ◽  
Cost Effective ◽  
Black Pepper ◽  
Piper Nigrum ◽  
Ms Analysis ◽  
Chemical Profiles ◽  
High Concentrations

AbstractThe growing demand and commercial value of black pepper (Piper nigrum) has resulted in considerable interest in developing suitable and cost-effective methods for chemical characterization and quality evaluation purposes. In the current study, an extensive set of oil samples (n = 23) that were extracted by steam distillation from black pepper seeds was investigated to compare the chemical profiles of samples originating from nine major producing countries, as well as to identify potential chemical markers for quality evaluation. The twenty-two most abundant volatile compounds, mainly terpenes, in these oils were determined by conventional GC/MS analysis. Principal component analysis with this set of data revealed distinct clusters for samples that originated from China and Malaysia. Relatively low concentrations of sabinene (< 0.2%) and high concentrations of 3-carene (10.9 – 21.1%) were observed in these samples, respectively, compared to oil samples from other countries. The enantiomeric distributions of key terpene markers, viz., β-pinene, sabinene, limonene, and terpinen-4-ol, were determined by chiral GC/MS analysis. Interestingly, for these four monoterpenes, levo-isomers were found to be predominant, emphasizing the highly conserved enzymatic processes occurring in P. nigrum. Moreover, consistent enantiomeric ratios ((−) isomer/(+) isomer) of 92.2 ± 3.0% for β-pinene, 94.8 ± 2.8% for sabinene, 60.7 ± 1.1% for limonene, and 78.3 ± 1.3% for terpinen-4-ol were observed, independent of geographical location. These results demonstrate the potential of using stereospecific compositions as chiral signatures for establishing the authenticity and quality of black pepper oil.

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