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Wyszukujesz frazę "noise transmission" wg kryterium: Temat


Tytuł:
Jak zmniejszyć hałas w ruchu drogowym
Autorzy:
Siedlecka, A.
Powiązania:
https://bibliotekanauki.pl/articles/363989.pdf
Data publikacji:
2011
Wydawca:
Nowoczesne Budownictwo Inżynieryjne
Tematy:
hałas
osłona przeciwhałasowa
ruch drogowy
noise
protection against noise transmission
traffic
Opis:
10 maja br. w Kielcach, podczas targów AUTOSTRADA-POLSKA, odbyła się konferencja Osłony przeciwhałasowe w ruchu drogowym, zorganizowana przez Instytut Badawczy Dróg i Mostów. Uroczystego otwarcia konferencji dokonali prof. dr hab. inż. Leszek Rafalski, dyrektor Instytutu, Andrzej Mochoń, prezes Targów Kielce, oraz Konrad Jaskóła, prezes zarządu Polimeksu-Mostostalu SA.
Źródło:
Nowoczesne Budownictwo Inżynieryjne; 2011, 4; 24
1734-6681
Pojawia się w:
Nowoczesne Budownictwo Inżynieryjne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of noise transmission of a machine tool enclosure
Autorzy:
Bleicher, Friedrich
Reichl, Christoph
Linhardt, Felix
Wimberger, Peter
Habersohn, Christoph
Krall, Stephan
Powiązania:
https://bibliotekanauki.pl/articles/99968.pdf
Data publikacji:
2019
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
sound pressure level
machine enclosure
noise transmission
acoustic grid
Opis:
Machine tools are highly integrated mechatronic systems consisting of dedicated mechanic design and integrated electrical equipment – in particular drive systems and the CNC-control – to realize the complex relative motion of tool towards work piece. Beside the process related capabilities, like static and dynamic stiffness as well as accuracy behavior and deviation resistance against thermal influence, safety aspects are of major interest. The machine tool enclosure must fulfill multiple requirements like retention capabilities against the moving parts of broken tools, lose work pieces or clamping components. In regular use, the noise emission have to be inhibited at the greatest possible extent by the machine tool enclosure. Nevertheless, the loading door and the moving parts of the workspace envelope are interfaces where noise transmission is harder to be avoided and therefore local noise emissions increase. The aim of the objective investigation is to analyse the noise emission of machine tools to determine the local noise transmission of a machine tool enclosure by using arrays of microphones. By the use of this measuring method, outer surfaces at the front, the side and on the top of the enclosure have been scanned. The local transient acoustic pressures have been recorded using a standard noise source placed on the machine table. In addition, an exemplary manufacturing process has been performed to analyse the frequency dependent location resolved sound emissions.
Źródło:
Journal of Machine Engineering; 2019, 19, 3; 5-16
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on Sound Transmission across a Floating Floor in a Residential Building by Using SEA
Autorzy:
Huang, Xianfeng
Lu, Yimin
Qu, Chen
Zhu, Chenhui
Powiązania:
https://bibliotekanauki.pl/articles/1953500.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
sound transmission
floating floor
impact noise
sound insulation
Opis:
For the purpose of reducing the impact noise transmission across floating floors in residential buildings, two main sound transmission paths in the floating floor structure are considered: the stud path and the cavity path. The sound transmission of each path is analysed separately: the sound transmission through the cavity and the stud are predicted by statistical energy analysis (SEA). Then, the sound insulation prediction model of the floating floor is established. There is reasonable agreement between the theoretical prediction and measurement, and the results show that a resilient layer with low stiffness can attenuate the sound bridge effect, resulting in higher impact noise insulation. Then, the influences of the floor covering, the resilient layer and the floor plate on the impact sound insulation are investigated to achieve the optimised structure of the floating floor based on the sound insulation.
Źródło:
Archives of Acoustics; 2021, 46, 1; 183-194
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acoustics of Classrooms in Primary Schools - Results of the Reverberation Time and the Speech Transmission Index Assessments in Selected Buildings
Autorzy:
Mikulski, W.
Radosz, J.
Powiązania:
https://bibliotekanauki.pl/articles/177048.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
primary school noise
reverberation time
speech transmission index
STI
Opis:
The article presents results of our own research regarding acoustic properties of 110 classrooms in five typical primary schools in Warsaw. The target of the re- search was to assess the classrooms using established criteria. These criteria include the reverberation time and the speech transmission index. The research has shown a large diversity of acoustic properties of classrooms within each of the schools and between the schools, resulting from the classroom equipment and the school building construction. In addition, the assessment has indicated that classrooms in schools researched do not meet the established acoustic criteria (reverberation time and speech transmission index). Because the classroom equipment is different for younger forms (integrated teaching) and for older forms (subject teaching), the results have been analyzed separately for rooms for younger forms (0–III) and for rooms for older forms (IV–VI). Synthetic results prove the advisability of such di- vision. Correlation analysis has been conducted for the speech transmission index STI and reverberation time Tmf , as well as for the speech transmission index STI and the suggested reverberation time Twf defined in a similar manner as Tmf , but in a wider frequency range. The correlation between the speech transmission index STI and Twf is higher than that between the STI index and Tmf . The reverberation time Twf can therefore be used for a more precise assessment of acoustic properties of interiors with regard to verbal communication than Tmf . In addition, the paper presents estimated analysis results of the influence of selected classroom equipment (carpets) on its acoustic properties.
Źródło:
Archives of Acoustics; 2011, 36, 4; 777-793
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sound transmission of sandwich beams with the dynamic vibration absorbers
Transmisja dźwięku poprzez płyty warstwowe z dynamicznymi absorberami drgań
Autorzy:
Diveyev, B.
Kernytskyy, I.
Kopytko, M.
Konyk, S.
Kogut, V.
Powiązania:
https://bibliotekanauki.pl/articles/886602.pdf
Data publikacji:
2015
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
sound transmission
beam
dynamic vibration absorber
noise
vibration
industrial machine
Źródło:
Scientific Review Engineering and Environmental Sciences; 2015, 24, 2[68]
1732-9353
Pojawia się w:
Scientific Review Engineering and Environmental Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sensor Hop-based Energy Efficient Networking Approach for Routing in Underwater Acoustic Communication
Autorzy:
Kohli, S.
Bhattacharya, P. P.
Powiązania:
https://bibliotekanauki.pl/articles/309397.pdf
Data publikacji:
2017
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
attenuation
clustering
multi-hop routing
signal-to-noise ratio
transmission loss
Opis:
Underwater Wireless Sensor Networks are deployed to explore the world under the water, measure different parameters and communicate the data to the surface, in the widespread applications. The main operating technology of these networks is the acoustic communication. The communication among the sensors and finally to the surface station requires a routing protocol. The sensors being battery limited and unfeasible to be replaced under the water requires an energy efficient routing protocol. Clustering imparted in routing is an energy saving technique in sensor networks. The routing may involve single or multi hop communication in the sensor networks. The paper gives a comparative study of the benchmark protocol multi-hop LEACH with the proposed Sensor Hop-based Energy Efficient Networking Approach (SHEENA) for the shallow as well as deep water in three dimensional Underwater Wireless Sensor Networks. The network energy model for the Underwater Wireless Sensor Networks is based among the different acoustic channel characteristics. The proposed approach is found to give better response.
Źródło:
Journal of Telecommunications and Information Technology; 2017, 1; 44-49
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis and Modelling on Radiated Noise of a Typical Fishing Boat Measured in Shallow Water Inspired by AQUO Project’s Model
Autorzy:
Peng, Z.
Fan, J.
Wang, B.
Powiązania:
https://bibliotekanauki.pl/articles/177092.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
radiated noise
South China Sea
predicted model
shallow water
transmission loss
Opis:
The shipping noise near channels and ports is an important contribution to the ambient noise level, and the depth of these sites is often less than 100 m. However less attention has been paid to the measurement in shallow water environments (Brooker, Humphrey, 2016). This paper presents extensive measurements made on the URN (underwater radiated noise) of a small fishing boat in the South China Sea with 87 m depth. The URN data showed that the noise below 30 Hz was dominated by the background noise. The transmission loss (TL) was modelled with FEM (finite element method) and ray tracing according to the realistic environmental parameters in situ. The discrepancy between the modelled results and the results using simple law demonstrates both sea surface and bottom have significant effect on TL for the shallow water, especially at low frequencies. Inspired by the modelling methodology in AQUO (Achieve QUieter Oceans) project (Audoly et al., 2015), a predicted model applied to a typical fishing boat was built, which showed that the URN at frequencies below and above 100 Hz was dominated by non-cavitation propeller noise and mechanical noise, respectively. The agreement between predicted results and measured results also demonstrates that this modelling methodology is effective to some extent.
Źródło:
Archives of Acoustics; 2018, 43, 2; 263-273
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:
Research on the Performance Optimization of Turbulent Self-Noise Suppression and Sound Transmission of Acoustic Windows Made from Functionally Graded Material
Autorzy:
Li, Bing
Zhou, Fu-Lin
Fan, Jun
Wang, Bin
Tan, Liwen
Powiązania:
https://bibliotekanauki.pl/articles/31339793.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
functionally graded material
acoustic window
turbulent self-noise
sound transmission loss
optimization
Opis:
For a simplified sonar dome model, an optimization method for internal gradients of functionally graded material (FGM) acoustic windows is proposed in this paper. This method can be used to design optimized FGM acoustic windows with better turbulent self-noise suppression and sound transmission performances. A theoretical model of FGM acoustic windows to evaluate the reduction of self-noise caused by the turbulent boundary layer (TBL) pulsating pressure and the sound transmission loss (STL) is derived through the double Fourier transform and the wavenumber frequency spectrum analysis, respectively, based on the transfer matrix idea and the classical elastic theory. The accuracy of the theory is verified by the finite element results of COMSOL Multiphysics. Utilizing the genetic algorithm (GA) and taking the monotonic gradient as the constraint condition, the internal gradient optimization method of FGM acoustic windows obtains the optimization variables in the Bernstein polynomial when the optimization objective is minimized by iterating the optimization variables in the deviation function represented by the Bernstein polynomial that is introduced in the gradient function. The STL, the turbulent self-noise reduction or a weighting function of the STL and turbulent self-noise reduction of FGM acoustic windows is chosen as the optimization objective. The optimization calculation of the sound transmission or turbulent self-noise suppression performances is carried out for the FRP-rubber FGM (FGM with fiber reinforced plastic (FRP) as the substrate material and rubber as the top material) acoustic window. The optimized results show that both the sound transmission and turbulent self-noise suppression performance are effectively improved, which verifies the effectiveness of the optimization method. Finally, the mechanism of the sound transmission and self-noise suppression characteristics before and after optimization are explained and analyzed based on the equivalent model of graded materials. The research results of this paper provide a reference value for the future design of FGM acoustic windows for sonar domes.
Źródło:
Archives of Acoustics; 2023, 48, 4; 475-495
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chinese Word Identification and Sentence Intelligibility in Primary School Classrooms
Autorzy:
Peng, J.
Powiązania:
https://bibliotekanauki.pl/articles/177322.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
speech identification
reverberation time
signal-to-noise ratio
classroom
speech transmission index
children
Opis:
The Chinese word identification and sentence intelligibility are evaluated by grades 3 and 5 students in the classrooms with different reverberation times (RTs) from three primary school under different signal-to-noise ratios (SNRs). The relationships between subjective word identification and sentence intelligibility scores and speech transmission index (STI) are analyzed. The results show that both Chinese word identification and sentence intelligibility scores for grades 3 and 5 students in the classroom increased with the increase of SNR (and STI), increased with the increase of the age of students, and decreased with the increase of RT. To achieve a 99% sentence intelligibility score, the STIs required for grades 3, grade 5 students, and adults are 0.71, 0.61, and 0.51, respectively. The required objective acoustical index determined by a certain threshold of the word identification test might be underestimated for younger children (grade 3 students) in classroom but overestimated for adults. A method based on the sentence test is more useful for speech intelligibility evaluation in classrooms than that based on the word test for different age groups. Younger children need more favorable classroom acoustical environment with a higher STI than older children and adults to achieve the optimum speech communication in the classroom.
Źródło:
Archives of Acoustics; 2016, 41, 2; 213-219
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acoustical properties of layered beams with attached dynamic vibration absorbers
Właściwości akustyczne belek wielowarstwowych z przyłączonymi dynamicznymi absorberami
Autorzy:
Divejev, B.
Kernytskyy, I.
Grygoryshyn, O.
Kogut, V.
Powiązania:
https://bibliotekanauki.pl/articles/887075.pdf
Data publikacji:
2012
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
acoustic property
layered beam
beam
sound transmission
laminated structure
dynamic vibration absorber
noise
Źródło:
Scientific Review Engineering and Environmental Sciences; 2012, 21, 4[58]
1732-9353
Pojawia się w:
Scientific Review Engineering and Environmental Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Noninvasive monitoring with strongly absorbed light
Autorzy:
McEwen, M P
Reynoldsk, J
Powiązania:
https://bibliotekanauki.pl/articles/174216.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
biomedical photonics
LED energisation
noise cancellation
photodiode
pulsed circuitry
absorption
noninvasive
photoplethysmography
pulse oximetry
transmission
Opis:
The transmission of light through tissue is used in noninvasive monitoring, in particular photoplethysmography. Investigations involving the transmission of wavelengths absorbed by bilirubin (short wavelength visible light) have been limited, due to strong absorption by haemoglobin. Achieving transmission of these wavelengths through tissue may advance noninvasive monitoring of substances like bilirubin. This work investigates the use of high power light sources together with improvements in signal-to-noise ratio as a means of enabling the transmission of strongly absorbed light through tissue. A custom device using multiple high-power short-wavelength visible light sources together with low power red and infrared sources, and background light cancellation – to improve signal-to-noise ratio, was constructed. Transmission of 454–1200 nm light through tissue was achieved, with pulsations present in measured signals. The transmission through tissue of multiple wavelengths of strongly absorbed light can be achieved by using high power light sources in conjunction with cancelling the effect of background light. Use of these techniques may allow investigations into the noninvasive monitoring of substances such as bilirubin using photoplethysmography.
Źródło:
Optica Applicata; 2014, 44, 2; 177-190
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Testing Time and Frequency Fiber-Optic Link Transfer by Hardware Emulation of Acoustic-Band Optical Noise
Autorzy:
Lipiński, M.
Krehlik, P.
Śliwczyński, Ł.
Buczek, Ł.
Kołodziej, J.
Powiązania:
https://bibliotekanauki.pl/articles/221890.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Time and Frequency fiber-optic transfer
phase noise in optical fiber
timing jitter
fiber-optic transmission
Opis:
The low-frequency optical-signal phase noise induced by mechanical vibration of the base occurs in field-deployed fibers. Typical telecommunication data transfer is insensitive to this type of noise but the phenomenon may influence links dedicated to precise Time and Frequency (T&F) fiber-optic transfer that exploit the idea of stabilization of phase or propagation delay of the link. To measure effectiveness of suppression of acoustic noise in such a link, a dedicated measurement setup is necessary. The setup should enable to introduce a low-frequency phase corruption to the optical signal in a controllable way. In the paper, a concept of a setup in which the mechanically induced acoustic-band optical signal phase corruption is described and its own features and measured parameters are presented. Next, the experimental measurement results of the T&F transfer TFTS-2 system’s immunity as a function of the fibre-optic length vs. the acoustic-band noise are presented. Then, the dependency of the system immunity on the location of a noise source along the link is also pointed out.
Źródło:
Metrology and Measurement Systems; 2016, 23, 2; 309-316
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Technical Notes : Practical Concerns Associated with Single-Number Ratings in Measuring Sound Transmission Loss Properties of Partition Panels
Autorzy:
Garg, N.
Kumar, A.
Maji, S.
Powiązania:
https://bibliotekanauki.pl/articles/177637.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Sound Transmission Loss
Sound Transmission Class
spectrum adaptation terms
ISO 717-1
weighted sound reduction index
spectrum adaptation term corresponding to noise source
Cx
TL
STC
Opis:
The paper presents an extensive review investigating the practical aspects related to the use of single- number ratings used in describing the sound insulation performance of partition wall panels and practical complications encountered in precise measurements in extensive frequency range from 50 Hz to 5 kHz. SWOT analysis of various single number ratings is described. A laboratory investigation on a double wall partition panel combination revealed the significant dependence of STC rating on transmission loss at 125 Hz attributed to 8 dB rule. An investigation conducted on devising alternative spectrums of aircraft noise, traffic noise, vehicular horn noise and elevated metro train noise as an extension to ISO 717-1 Ctr for ascertaining the sound insulation properties of materials exclusively towards these noise sources revealed that the single-number rating Rw + Ctr calculated using ISO 717-1 Ctr gives the minimum sound insulation, when compared with Rw + Cx calculated using the alternative spectrums of aircraft noise, traffic noise, etc., which means that material provides a higher sound insulation to the other noise sources. It is also observed that spectrum adaptation term Cx calculated using the spectrum of noise sources having high sound pressure levels in lower frequencies decreases as compared to ISO 717-1 Ctr owing to significant dependence of Ctr at lower frequencies.
Źródło:
Archives of Acoustics; 2013, 38, 1; 115-124
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
How to assess and improve the quality of voice services in telephone communication and alarm systems in mines
Możliwości oceny i poprawy jakości usług głosowych w kopalnianych systemach łączności telefonicznej i alarmowej
Autorzy:
Miśkiewicz, K.
Wojaczek, A.
Powiązania:
https://bibliotekanauki.pl/articles/1360932.pdf
Data publikacji:
2016
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
łączność telefoniczna
łączność alarmowa
bezpieczeństwo
telekomunikacja
transmisja głosu
redukcja szumów
telephone communication
alarm communication
safety
telecommunication
voice transmission
noise reduction
Opis:
The article presents selected objective and subjective methods to assess the quality of voice services in telephone communication. The authors described the impact of the line and acoustic echo phenomena and ambient noise on the functions of telephone communication systems with respect to the speakerphone mode. Additionally, they discussed the possibilities to apply digital technology to improve the quality of voice services in telephone communication and alarm systems.
Przedstawiono wybrane metody oceny jakości usług głosowych w telefonii z uwzględnieniem metod subiektywnych i obiektywnych. Opisano wpływ zjawiska echa akustycznego i liniowego oraz hałasu otoczenia na funkcjonowanie systemów łączności telefonicznej z uwzględnieniem trybu głośnomówiącego. Omówiono możliwości zastosowania techniki cyfrowej dla poprawy jakości usług głosowych w kopalnianych systemach łączności telefonicznej i alarmowej.
Źródło:
Mining – Informatics, Automation and Electrical Engineering; 2016, 54, 2; 40-47
2450-7326
2449-6421
Pojawia się w:
Mining – Informatics, Automation and Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł

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