Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "level" wg kryterium: Temat

  Lista filtrów
Wyrównaj
Wyświetlanie 1-15 z 26
Tytuł:
Evaluation and Analysis of Environmental Noise Pollution in Seven Major Cities of India
Autorzy:
Garg, N.
Sinha, A. K.
Dahiya, M.
Gandhi, V.
Bhardwaj, R. M.
Akolkar, A. B.
Powiązania:
https://bibliotekanauki.pl/articles/177396.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
NANMN
National Ambient Noise Monitoring Network
day equivalent level
Lday
night equivalent level
Lnight
day-night average sound level
Ldn
equivalent continuous sound pressure level
LAeq,24h
Opis:
The paper describes the noise monitoring data acquired from the pilot project on the establishment of National Ambient Noise Monitoring Network (NANMN) across seven major cities in India for continuous noise monitoring throughout the year. The annual average Lday (06–22 h) and Lnight (22–06 h) values observed in year 2011–2014 for the 35 locations under study in which 14 locations are in commercial zone, 5 in Industrial, 7 in residential and 9 in silence zones are described. The long-term noise monitoring shows that ambient noise levels have marginally increased for 29 sites (82.9%) since past four years. The present study is focused on evaluation and analysis of environmental noise pollution at 35 noise monitoring sites in seven major cities of India and shall be instrumental in planning for the noise abatement measures for controlling the noise pollution in these sites.
Źródło:
Archives of Acoustics; 2017, 42, 2; 175-188
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Multi-Level Robust and Perceptually Transparent Blind Audio Watermarking Scheme Using Wavelets
Autorzy:
Husain, F.
Farooq, O.
Khan, E.
Powiązania:
https://bibliotekanauki.pl/articles/176447.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
digital audio watermarking
robustness
single-level watermarking
multi-level watermarking
payload capacity
Opis:
In this paper, a robust and perceptually transparent single-level and multi-level blind audio watermark- ing scheme using wavelets is proposed. A randomly generated binary sequence is used as a watermark, and wavelet function coding is used to embed the watermark sequence in audio signals. Multi-level wa- termarking is used to enhance payload capacity and can be used for a different level of security. The robustness of the scheme is evaluated by applying different attacks such as filtering, sampling rate al- teration, compression, noise addition, amplitude scaling, and cropping. The simulation results obtained show that the proposed watermarking scheme is resilient to various attacks except cropping. Perceptual transparency of watermark is measured by using Perceptual Evaluation of Audio Quality (PEAQ) ba- sic model of ITU-R (PEAQ ITU-R BS.1387) on Speech Quality Assessing Material (SQAM) given by European Broadcasting Union (EBU). Average Objective Difference Grade (ODG) measured for this method is −0.067 and −0.080 for single-level and multi-level watermarked audio signals, respectively. In the proposed single-level digital audio watermarking scheme, the payload capacity is increased by 19.05% as compared to the single-level Chirp-Based Digital Audio Watermarking (CB-DAWM) scheme.
Źródło:
Archives of Acoustics; 2014, 39, 4; 529-539
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On Suitability of Day-Night Average Sound Level Descriptor in Indian Scenario
Autorzy:
Garg, Naveen
Powiązania:
https://bibliotekanauki.pl/articles/177734.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
National Ambient Noise Monitoring Network
NANMN
day equivalent sound level
Lday
night equivalent sound level
Lnight
day-night average sound level
Ldn
day-evening-night average sound level
Lden
equivalent continuous sound level
LAeq,24h
Opis:
The paper analyzes the monthly day equivalent levels, Lday (06-22 h) and night equivalent levels, Lnight (22-06 h) values observed in year 2015 and 2016 for the 70 locations whereby continuous noise monitoring is conducted under the National Ambient Noise Monitoring Network (NANMN). The study exclusively analyzes the ambient noise data acquired for 25 locations in commercial zone, 12 in industrial, 16 in residential and 17 in silence zones. The analysis of (Lday – Lnight) for 70 locations under observations reveals that 10 dB night time adjustment in day-night average sound level descriptor is not appropriate in such a scenario and as such it is recommended to use day-night average sound level and day-eveningnight average sound level descriptors without any 10 dB night time adjustment or 5 dB evening time adjustments. The analysis and conclusions of the present study shall be very useful for developing single value noise descriptor correlating the noise annoyance and health effects in Indian perspectives.
Źródło:
Archives of Acoustics; 2019, 44, 2; 385-392
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation and Analysis of Long-term Environmental Noise Levels in 7 Major Cities of India
Autorzy:
Garg, Naveen
Kumar, Saurabh
Gautam, Chitra
Gandhi, Vishal
Gupta, Nalin Kumar
Powiązania:
https://bibliotekanauki.pl/articles/31339933.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
National Ambient Noise Monitoring Network
NANMN
day equivalent sound level
Lday
night equivalent sound level
Lnight
Opis:
This paper describes the long-term noise monitoring data for ten consecutive years (2011–2020) acquired from the diversified National Ambient Noise Monitoring Network (NANMN) set up across 7 major cities of India and consisting of 70 stations for continuous noise monitoring throughout the year. The annual average ambient noise levels observed throughout these ten years in 70 locations under study, including 25 locations in commercial zones, 12 in industrial, 16 in residential, and 17 in silence zones, are described. The noise scenario in these ten years is compared and analyzed. It is observed that no site in residential or silence zones meets the ambient noise limits for the past ten years. The study suggests guidelines for a policy framework for environmental noise management and control to regulate noise pollution in Indian cities.
Źródło:
Archives of Acoustics; 2023, 48, 1; 103-126
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acoustic Analysis Using Sound Level Meter to Determine the Period of Usage of the Spindle Bearing of a Radial Drilling Machine
Autorzy:
Charles, S.
Vijaya, Joslin D.
Powiązania:
https://bibliotekanauki.pl/articles/176769.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
acoustical condition monitoring
radial drilling machine
spindle bearing
sound level meter
sound pressure level
sound muting transducer
Opis:
The condition monitoring techniques like acoustic emission, vibration analysis, and infrared thermography, used for the failure diagnosis of bearings, require longer processing time, as they have to per form acoustical measurement followed by signal processing and further analysis using special software. However, for any bearing, its period of usage can be easily determined within an hour, by measuring the bearing sound, using sound level meter (SLM). In this paper the acoustical analysis of the spindle Bering of a radial drilling machine was performed using SLM, by measuring the sound pressure level of the bearing in decibels, for different frequencies, while muting all the other noises. Then using an experimental set up, two database readings were taken, one for new bearing and the other for completely damaged bearing, both are SKF6207, which itself is the spindle bearing. From these three sets of sound pressure level readings, the period of usage of the spindle bearing, was calculated using an interpolation equation, by substituting the life of the bearing from the manufacturer’s catalogue. Therefore, for any machine with a SKF6207 bearing, its usage time can be estimated using the database readings and one measurement on that machine, all with the same speed.
Źródło:
Archives of Acoustics; 2019, 44, 3; 505-510
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of Acoustic Treatment on Music Teachers’ Exposure to Sound
Autorzy:
Kozłowski, E.
Młyński, R.
Powiązania:
https://bibliotekanauki.pl/articles/177728.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
music teachers
sound pressure level
acoustic treatment
Opis:
In this study, music teachers’ exposure to sound was tested by measuring the A-weighted equivalent sound pressure level (SPL), the A-weighted maximum SPL and the C-weighted peak SPL. Measurements were taken prior to and after acoustic treatment in four rooms during classes of trumpet, saxophone, French horn, trombone and percussion instruments. Results showed that acoustic treatment affects the exposure of music teachers to sound. Daily noise exposure levels (LEX, 8 h) for all teachers exceeded a limit of 85 dB while teaching music lessons prior to room treatment. It was found that the LEX, 8 h values ranged from 85.8 to 91.6 dB. The highest A-weighted maximum SPL and C-weighted peak SPL that music teachers were exposed to were observed with percussion instruments (LAmax = 110.4 dB and LCpeak = 138.0 dB). After the treatments, daily noise exposure level decreased by an average of 5.8, 3.2, 3.0, 4.2 and 4.5 dB, respectively, for the classes of trumpet, saxophone, French horn, trombone and drums, and did not exceed 85 dB in any case.
Źródło:
Archives of Acoustics; 2014, 39, 2; 159-163
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Relationship Between Chinese Speech Intelligibility of Elderly and Speech Transmission Index
Autorzy:
Peng, Jianxin
Zeng, Jiazhong
Zhao, Yuezhe
Powiązania:
https://bibliotekanauki.pl/articles/1953494.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
speech intelligibility
speech transmission index
signal-to-noise ratio
background noise level
speech sound pressure level
reverberation time
Opis:
In this paper, the relationship between Chinese speech intelligibility (CSI) scores of the elderly aged 60-69 and over 70 years old, and speech transmission index (STI) were investigated through the auralization method under different reverberation time and background noise levels (BNL, 40 dBA and 55 dBA). The results show that the CSI scores of the elderly are significantly worse than those of young adults. For the elderly over 70, the CSI scores become much lower than those of young adults. To be able to achieve the same CSI, the elderly, especially those over 70, need much higher STI and greater SNR than the young. The elderly aged 60-69 and over 70 need to improve their STI by 0.419 and 0.058 respectively under BNL 40 dBA, as well as 0.282 and 0.072 respectively under BNL 55 dBA, so as to obtain the same CSI scores as the young adults.
Źródło:
Archives of Acoustics; 2021, 46, 2; 229-235
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Technical Possibilities of Reducing the Sound Pressure Level Emitted into the Environment by a Power Transformer
Autorzy:
Borucki, S.
Boczar, T.
Cichoń, A.
Powiązania:
https://bibliotekanauki.pl/articles/177473.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
power transformer
corrected sound pressure level
noise
modernization
Opis:
The subject presented in this paper refers to measurements and assessment of the corrected sound pressure level values (noise) occurring around a medium-power transformer. The paper presents the values of noise accompanying the operation of the power object before and after its modernization, which consisted in repeated core pressing and replacement of the cooling system. The main aim of the research work was the assessment of the influence of the repair work on the noise level emitted into the environment.
Źródło:
Archives of Acoustics; 2011, 36, 1; 49-56
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Road, Tram and Aircraft Traffic Noise Annoyance Related to the Number of Noise Events and the Equivalent Sound Level
Autorzy:
Felcyn, Jan
Ptak, Patrycja
Powiązania:
https://bibliotekanauki.pl/articles/31339951.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
noise annoyance
noise event
transportation noise
sound level
Opis:
Noise mapping is based on long-term noise indicators, such as LN or LDEN. On the other hand, transportation intensity changes during a day (road traffic peak hours) or a year (more flights during holidays) and this variability is not reflected in single sound level values. We wanted to find out whether not only sound level but also the number of noise events is the factor influencing noise annoyance assessment. Ambisonic recordings of real traffic in a city were used. Road, tramway, and aircraft traffic were investigated and two factors were manipulated: the equivalent sound level value and the number of noise events. All stimuli were presented in an anechoic chamber. The results showed that sound level is always a statistically significant parameter while the number of events has an impact only for tramways and airplanes. Moreover, the difference is observed only between one or more subgroups, no matter what the sound level value was. For road traffic this relation was not found to be statistically significant. It was also shown that the existence of tramway bonus or airplane malus is linked with the number of noise events.
Źródło:
Archives of Acoustics; 2022, 47, 4; 457-467
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Measurements and Assessment of Sound Emitted by Toys Intended for Children under the Age of Three Years Old
Autorzy:
Grynkiewicz-Bylina, B.
Rakwic, B.
Powiązania:
https://bibliotekanauki.pl/articles/177756.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
toys
sound level
noise
hazards
safety of use
Opis:
Toys emitting sounds are classified as significant sources of noise found in the children environment. Impulse and continuous noise emitted by toys, used in close to the child’s ear, acting directly on the organ of hearing, can lead to serious adverse health effects. This is especially true for children under the age of three, in which the state of the hearing organ determines their intellectual development. The current level of safety of sound emitting toys intended for children in this age group is insufficient. This is confirmed by the reports from the control of market surveillance authorities. A new approach to the assessment of children’s exposure to noise generated by toys, included in EN 71-1:2011 + A2:2013 Standard, based on the permissible values applicable to the workplaces, requires further tests and verification. The paper presents the results of the research work and assesses the level of sound emitted by toys in the light of current standard requirements, carried out using the author’s methodology. Toys intended for children under the age of 3 years, commercialized on the European market by Polish manufacturers and importers were tested. The results of the tests allowed us to determine the impact of duration of the sound pressure level measurement on the final result.
Źródło:
Archives of Acoustics; 2015, 40, 3; 383-393
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Loudness Assessment of Musical Tones Equalized in A-weighted Level
Autorzy:
Klonari, D.
Pastiadis, K.
Papadelis, G.
Papanikolaou, G.
Powiązania:
https://bibliotekanauki.pl/articles/177354.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
loudness perception
A-weighted level equalization
wind instrument sounds
Opis:
The present study was carried out to determine whether recorded musical tones played at various pitches on a clarinet, a flute, an oboe, and a trumpet are perceived as being equal in loudness when presented to listeners at the same A-weighted level. This psychophysical investigation showed systematic effects of both instrument type and pitch that could be related to spectral properties of the sounds under consideration. Level adjustments that were needed to equalize loudness well exceeded typical values of JNDs for signal level, thus confirming the insufficiency of A-weighting as a loudness predictor for musical sounds. Consequently, the use of elaborate computational prediction is stressed, in view of the necessity for thorough investigation of factors affecting the perception of loudness of musical sounds.
Źródło:
Archives of Acoustics; 2011, 36, 2; 239-250
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis and Optimization of Micro Speaker-Box Using a Passive Radiator in Portable Device
Autorzy:
Jiang, Y.-W.
Kwon, J.-H.
Kim, H.-K.
Hwang, S.-M.
Powiązania:
https://bibliotekanauki.pl/articles/176530.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
passive radiator
speaker box
SPL improvement
Sound Pressure Level
Opis:
With the rapid development of multimedia devices such as smart phones and tablet PCs, microspeakers have been recently increasingly used for audio equipment. Improving the acoustic performance of a microspeaker is always a main concern, especially in the low frequency range. To avoid sound cancelation, a microspeaker unit is usually inserted into a speaker box. A passive radiator is also used in speaker boxes to improve the sound performance in the loudspeaker system. However, passive radiators have not been applied into microspeaker system. In this study, a speaker box with a passive radiator was analyzed and optimized to achieve a higher Sound Pressure Level (SPL) in a microspeaker system. The Finite Element Method (FEM), two-degree-of-freedom (DOF) vibration theory, and a plane circular piston sound source were used to study the electromagnetic, vibration, and acoustic characteristics, respectively. Optimization was conducted by changing the mass, stiffness, and size of the passive radiator. Based on the optimized parameters, a new sample was manufactured. The experiment results show that the SPL of the optimized speaker box with a passive radiator is improved by 5 dB at 200 Hz compared with the one without a radiator. The analysis results also matched the experiment results.
Źródło:
Archives of Acoustics; 2017, 42, 4; 753-760
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Microscopic Prediction Model for Traffic Noise in Adjacent Regions to Arterial Roads
Autorzy:
Li, Ming
Liu, Jizhou
Powiązania:
https://bibliotekanauki.pl/articles/31339809.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
traffic noise
arterial roads
noise prediction method
microscopic level
Opis:
Traffic noise in big cities impacts the people who live and work in high-rise buildings alongside arterial roads. To determine this impact magnitude, this paper proposes and validates a microscopic level method that locally predicts the total noise level and the spectral characteristics of traffic flow in the near-road region. In the proposed method, the vehicles on the road are considered as multiple queues of moving point sound sources with ground reflection considered. To account for the flow of vehicles on the road, traffic field data, and individual vehicle noise source models are also employed. A field measurement is conducted to validate the proposed method. Results comparison shows that the predicted and the measured overall A-weighted sound pressure level and A-weighted noise spectra are within 3 dBA and 5 dBA, respectively. Based on the validated method, the spatial distribution of traffic noise near the arterial road is investigated for different traffic scenarios.
Źródło:
Archives of Acoustics; 2023, 48, 3; 433-449
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Fast Method of Feature Extraction for Lowering Vehicle Pass-By Noise Based on Nonnegative Tucker3 Decomposition
Autorzy:
Wang, H.
Cheng, G.
Deng, G.
Li, X.
Li, H.
Huang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/177883.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
vehicle pass-by noise
NTD
feature extraction
sound pressure level
Opis:
Usually, the judgement of one type fault of vehicle pass-by noise is difficult for engineers, especially when some significant features are disturbed by other interference noise, such as the squealing noise is almost simultaneous with the whistle in the exhaust system. In order to cope with this problem, a new method, with the antinoise ability of the algorithm on the condition by which the features are entangled, is developed to extract clear features for the fault analysis. In the proposed method, the nonnegative Tucker3 decomposition (NTD) with fast updating algorithm, signed as NTD_FUP, can find out the natural frequency of the parts/components from the exhaust system. Not only does the NTD_FUP extract clear features from the confused noise, but also it is superior to the traditional methods in practice. Then, an aluminium-foil alloy material, which is used for the heat shield for its lower noise radiation, replaces the aluminium alloy alone. Extensive experiments show that the sound pressure level of the vehicle pass-by noise is reduced 0.9 dB(A) by the improved heat shield, which is also considered as a more lightweight design for the exhaust system of an automobile.
Źródło:
Archives of Acoustics; 2017, 42, 4; 619-629
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Overview of the Noise Levels Measured in Industrial Facilities in Serbia and Implemented Methods of Protection
Autorzy:
Luburić, Uranija Kozmidis
Samardžić, Selena
Lakatoš, Robert
Mihailović, Aleksandra
Veselinović, Milka
Powiązania:
https://bibliotekanauki.pl/articles/176762.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
noise
industry
SPL
sound pressure level
frequency analysis
noise protection
Opis:
Noise is one of the most significant factors which not only disturbs working conditions, but has a large impact on workers’ health. This problem has existed in industries since the beginning and, despite technical and other solutions, it has not been solved. There is a large number of papers, supported with very detailed analyses, that investigate noise levels in industry or contain questionnaires about the impact of noise on workers’ overall health and work abilities. The purpose of this paper is to contribute to the global picture of sustainability and the development of strategies for improving the quality of working environment, with special attention to the generation of noise in different production processes in thirteen different industries in Novi Sad, Serbia. The paper also seeks to examine the advantages and drawbacks of the implemented protective methods and to provide some recommendations for their better implementation in order to contribute to solving this significant problem of today.
Źródło:
Archives of Acoustics; 2020, 45, 3; 499-510
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 26

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies