Informacja

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

Wyszukujesz frazę "noise" wg kryterium: Temat


Tytuł:
Four-point probe resistivity noise measurements of GaSb layers
Autorzy:
Ciura, L.
Kolek, A.
Smoczyński, D.
Jasik, A.
Powiązania:
https://bibliotekanauki.pl/articles/201503.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
low frequency noise
GaSb noise
noise measurements
resistance noise calculation
Opis:
This paper concerns measurements and calculations of low frequency noise for semiconductor layers with four-probe electrodes. The measurements setup for the voltage noise cross-correlation method is described. The gain calculations for local resistance noise are performed to evaluate the contribution to total noise from different areas of the layer. It was shown, through numerical calculations and noise measurements, that in four-point probe specimens, with separated current and voltage terminals, the non-resistance noise of the contact and the resistance noise of the layer can be identified. The four-point probe method is used to find the low frequency resistance noise of the GaSb layer with a different doping type. For n-type and p-type GaSb layers with low carrier concentrations, the measured noise is dominated by the non-resistance noise contributions from contacts. Low frequency resistance noise was identified in high-doped GaSb layers (both types). At room temperature, such resistance noise in an n-type GaSb layer is significantly larger than for p-type GaSb with comparable doping concentration.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2020, 68, 1; 135-140
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Monitoring the Reaction and Response of People to Urban Noise
Autorzy:
Popescu, D. I.
Moholea, I. F.
Powiązania:
https://bibliotekanauki.pl/articles/178048.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
urban noise
noise pollution
noise annoyance
social survey
Opis:
An important aspect in assessing noise in urban agglomerations is the subjective one, which takes into account the sensitivity and specific reactions of residents to the noise in their living environment. This paper presents results of a sociological study initiated to determine the population awareness, regarding the urban acoustic environment and estimation of effects and disturbance. The survey was conducted in a Romanian city, to complement the information provided by the strategic noise map of the area. This approach allows the estimation of specific local patterns of reaction and response to urban noise of the exposed population and provides the information, needed to develop action plans and to set proper solutions for urban area planning.
Źródło:
Archives of Acoustics; 2010, 35, 2; 237-244
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Noise Analysis of Differential Multiport Networks : the Wave Approach
Autorzy:
Dobrowolski, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/226027.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
differential networks
noise analysis
noise waves
noise correlation matrix
differential noise figure
Opis:
In this paper there is presented and discussed a general analysis method for noise characterization of noisy multiport differential networks. It is based on mixed mode, differential and common mode, noise waves representation of noise, generalized mixed-mode scattering parameters and generalized mixed-mode noise wave correlation parameters for the network. There are derived analytical relation between the noise figure for a given output port and the noise matrix and the scattering parameters of the network, as well as the correlations between the input port noise waves. The signal to noise ratio degradation factor is derived and discussed, too. Presented results can be implemented directly in a CAD software noise analysis of differential microwave multiport networks with differential as well as with conventional single ended ports.
Źródło:
International Journal of Electronics and Telecommunications; 2014, 60, 4; 281-286
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cumulative Industrial Noise Impact on the Environment
Autorzy:
Wszołek, T.
Powiązania:
https://bibliotekanauki.pl/articles/178090.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
industrial noise
cumulative impact
noise indicators
cumulative noise levels
Opis:
The paper presents basic legal conditions, applicable to the calculation of cumulative noise levels in the environment with indication mainly on lack of detailed regulations both in formal and methodological approach for evaluating those levels. The paper is focused on methodological approach with the emphasis on analysis of existing case studies in the industry. The main subject of the analysis is the cumulation of industrial noise sources: newly designed and existing ones, together with a proposal of accumulate other types of the noise. Evaluation of cumulative noise levels for new (designed) objects is realised by computational methods, and for existing objects, by measurements or by combination of measurement and computational methods. It is assumed that the cumulative level is an energetic sum of the rating levels for all installations and it will not exceed the limit value in a given place. For the cumulation of different noise sources, the weighting for criterion values of these sources will be applied in aggregation.
Źródło:
Archives of Acoustics; 2017, 42, 2; 169-174
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Distrubuted system for noise threat evaluation based on psychoacoustic measurements
Autorzy:
Kotus, J.
Szczodrak, M.
Czyżewski, A.
Kostek, B.
Powiązania:
https://bibliotekanauki.pl/articles/220609.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
noise
environmental noise
dosimetry
measurements
Opis:
An innovative system designed for the continuous monitoring of acoustic climate of urban areas was presented in the paper. The assessment of environmental threats is performed using online data, acquired through a grid of engineered monitoring stations collecting comprehensive information about the acoustic climate of urban areas. The grid of proposed devices provides valuable data for the purpose of long and short time acoustic climate analysis. Dynamic estimation of noise source parameters and real measurement results of emission data are utilized to create dynamic noise maps accessible to the general public. This operation is performed through the noise source prediction employing a propagation model being optimized for computer cluster implementation requirements. It enables the system to generate noise maps in a reasonable time and to publish regularly map updates in the Internet. Moreover, the functionality of the system was extended with new techniques for assessing noise-induced harmful effects on the human hearing system. The principle of operation of the dosimeter is based on a modified psychoacoustic model of hearing and on the results of research performed with participation of volunteers concerning the impact of noise on hearing. The primary function of the dosimeter is to estimate, in real time, auditory effects which are caused by exposure to noise. The results of measurements and simulations performed by the system prototype are depicted and analyzed. Several cases of long-term and short-term measurements of noise originating from various sources were considered in detail. The presented outcomes of predicted degree of the hearing threshold shift induced during the noise exposure can increase the awareness of harmfulness of excessive sound levels.
Źródło:
Metrology and Measurement Systems; 2012, 19, 2; 219-230
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Hearing Threshold of Employees Exposed to Noise Generated by the Low-Frequency Ultrasonic Welding Devices
Autorzy:
Dudarewicz, A.
Zaborowski, K.
Rutkowska-Kaczmarek, P.
Zamojska-Daniszewska, M.
Śliwińska-Kowalska, M.
Zamysłowska-Szmytke, E.
Pawlaczyk-Łuszczyńska, M.
Powiązania:
https://bibliotekanauki.pl/articles/178077.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
noise-induced hearing loss
noise
ultrasonic noise
occupational exposure
Opis:
The aim of the study was to assess the hearing threshold levels (HTLs) in employees exposed to noise generated by low-frequency ultrasonic technological equipment in comparison with the HTLs of workers exposed to audible noise at the similar A-weighted equivalent-continuous sound pressure level. The study includes measurements of ultrasonic and audible noise at workplaces and hearing tests, i.e. conventional pure-tone audiometry and extended high-frequency audiometry. The study group comprised 90 workers, aged 41.4 ± 10.0 years (mean±SD), exposed for 17.3 ± 9.8 years to noise generated by ultrasonic devices at mean daily noise exposure level (‹LEX,8h›) of 80.6 ± 2.9 dB. The reference group consists of 156 subjects, exposed to industrial noise (without ultrasonic components) at similar A-weighted equivalent-continuous sound pressure level (‹LEX,8h› = 81.8 ± 2.7 dB), adjusted according to age (39.8 ± 7.7 years), gender and job seniority (14.0 ± 7.0 years). This group was selected from database collected in the Nofer Institute of Occupational Medicine. Audiometric hearing threshold levels in the frequency range of 0.5–6 kHz were similar in both groups, but in the frequency range of 8–12.5 kHz they were higher in the group of employees exposed to ultrasonic noise. The findings suggest that differences in the hearing threshold (at high frequencies) in analyzed groups may be due to differences in spectral composition of noise and show the need to continue the undertaken studies.
Źródło:
Archives of Acoustics; 2017, 42, 2; 199-205
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Impact of Fireworks Noise on the Acoustic Climate in Urban Areas
Autorzy:
Kukulski, B.
Wszołek, T.
Mleczko, D.
Powiązania:
https://bibliotekanauki.pl/articles/176479.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
impulsive noise
fireworks
environmental noise
Opis:
New Year’s Eve is an example of a situation in which urban residents are exposed to an almost continuous and increased noise level from the impulsive sounds sources – fireworks. This custom has become a source of many controversies related to the protection of human and animal health or environmental pollution. However, current legal regulations only slightly affect the subject of noise of fireworks and its harmfulness. Currently, it does not seem possible to completely prohibit the use of fireworks in urban areas, but this does not mean that it is not possible to decrease the degree of their annoyance. The paper consists the issues of identification, analysis and assessment of impulsive noise of fireworks and acoustic climate during New Year’s Eve. Material presented refers to measurements of time series, frequency spectrum and values of noise parameters of selected fireworks. It was presented, among others, that the measured values exceed the criteria for occupational noise (LCpeak), due to the direct hazard of hearing loss, from 1.8 dB at a distance of 25 m and 6.2 dB at a distance of 15 m. Also this work discusses results of impulsive noise measurements of fireworks recorded during New Year’s Eve in years 2016-2017. Material refers to measurements at three measurement points spread over the city of Kraków. Obtained results were compared with typical noise levels for night time in urban area, indicating also the main sources of annoyance and hazard from this type of noise.
Źródło:
Archives of Acoustics; 2018, 43, 4; 697-705
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Noise spectroscopy of resistive components at elevated temperature
Autorzy:
Stadler, A.W.
Zawiślak, Z.
Dziedzic, A.
Nowak, D.
Powiązania:
https://bibliotekanauki.pl/articles/221348.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
noise spectroscopy
low-frequency noise
resistance noise
low-frequency noise measurements
thick-film resistors
Opis:
Studies of electrical properties, including noise properties, of thick-film resistors prepared from various resistive and conductive materials on LTCC substrates have been described. Experiments have been carried out in the temperature range from 300 K up to 650 K using two methods, i.e. measuring (i) spectra of voltage fluctuations observed on the studied samples and (ii) the current noise index by a standard meter, both at constant temperature and during a temperature sweep with a slow rate. The 1/f noise component caused by resistance fluctuations occurred to be dominant in the entire range of temperature. The dependence of the noise intensity on temperature revealed that a temperature change from 300 K to 650 K causes a rise in magnitude of the noise intensity approximately one order of magnitude. Using the experimental data, the parameters describing noise properties of the used materials have been calculated and compared to the properties of other previously studied thick-film materials.
Źródło:
Metrology and Measurement Systems; 2014, 21, 1; 15-26
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
From the History of the Noise Control Conference
Autorzy:
Engel, Z. W.
Powiązania:
https://bibliotekanauki.pl/articles/177984.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
noise control
history of the noise control conference
noise threats
Opis:
In the article a short historical outline of noise control conferences organized in Poland is given. Those conferences with the participation of Polish specialists have been organized since 1964; since 1976 they have been evolved into International Noise Control Conferences. Silhouettes of four Polish scientists, which have made a large contribution to the noise and vibration control in Poland, are presented. Also the current state of threats by noise and vibrations have been briefly mentioned. The significance of such conferences has been emphasized.
Źródło:
Archives of Acoustics; 2010, 35, 2; 133-144
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Noise Characterization of Differential Multi-Element Multiport Networks : the Wave Approach
Autorzy:
Dobrowolski, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/226146.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
differential networks
differential noise figure
noise waves
noise correlation matrix
Opis:
In this paper there is presented and discussed a general analysis method for noise characterization of noisy multi-element multiport differential networks. It is based on mixed mode, differential and common mode, noise waves representation of noise, generalized mixed-mode scattering parameters and generalized mixed-mode noise wave correlation parameters for the network. There are derived analytical relation between the noise figure for a given output port and the noise matrix and the scattering parameters of the network, as well as the correlations between the input port noise waves. The signal to noise ratio degradation factor is derived and discussed, too. Presented results can be implemented directly in a CAD software for noise analysis of differential microwave multi-element multiport networks with differential as well as with conventional single ended ports.
Źródło:
International Journal of Electronics and Telecommunications; 2015, 61, 4; 395-401
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Differential Noise Figure and Gain De-Embedding : the Wave Approach
Autorzy:
Dobrowolski, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/226126.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
noise figure
differential noise figure
differential noise figure de-embedding
Opis:
The paper presents complete analysis of differential amplifier noise figure single-ended measurement setup. The analysis is based on scattering matrix representation for the network and wave representation for noise. As a result, there are presented equations allowing the differential amplifier gain and noise figure to be de-embedded with single-ended measurements. De-embedding equations are given for the balanced amplifier and for the fully differential amplifier.
Źródło:
International Journal of Electronics and Telecommunications; 2016, 62, 1; 65-69
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seasonal Change and Spatial Distribution of Traffic Noise in Seferihisar, Turkey
Autorzy:
Say, N.
Ökten, S. Ö.
Aysu, A.
Yalçinkaya, N. M.
Powiązania:
https://bibliotekanauki.pl/articles/176295.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
noise map
IDW
GIS
traffic noise
Opis:
In this study, traffic noise in Seferihisar, which is a holiday resort by the Aegean Sea in the West of Turkey, was investigated. The noise occurring in summer and winter, on weekdays, and at weekends was mapped separately. Besides, land uses exposed to traffic noise were specified. In the carried out method, the land uses were primarily mapped by using the satellite images of the study area. Then, the noise was measured at 46 points during ten days in summer and winter, on weekdays and at weekends, and it was mapped by using Inverse Distance Weighting (IDW) method and by means of Geographic Information System (GIS) techniques. The measurements were taken in the daytime (07:00-19:00), in the evening (19:00-23:00), and at night (23:00-07:00) as stated in the Turkish Regulation of Assessment and Management of Environmental Noise. Since the time interval of the daytime measurements was large, the noise was measured in three different periods for the daytime measurements. In the formation of noise maps, logarithmic averages of all measurements taken at each point were used. The noise maps were overlapped with the land use maps by the help of the GIS techniques; the land use affected by the noise was analyzed. The results showed that the road traffic noise varied from summer to winter seasons in the study area depending on heavy or light traffic. The noise occurring in summer showed an increase both on weekdays and at weekends. While the limit value was exceeded in 49 of the measurement averages taken in winter, the limit value was exceeded in 96 measurements taken in summer. The noise maps formed according to the IDW method displayed that the areas in which the limit value was exceeded in the daytime in summer took up 14.27% of the study area while this rate went down to 4.06% in winter. The study area is one of the most important destinations for summer holiday. 20.12% of the area that exceeded the limit value in summer was builtup and 10.69% of them was tourism area. The noise together with population and traffic that increase in summer season is an important environmental problem against which some precautions should be taken. The findings of the study present significant results which might guide local governments in preventing and managing the noise.
Źródło:
Archives of Acoustics; 2017, 42, 4; 631-642
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Pseudo-Noise Waveform Design Minimizing Range and Doppler Masking Effect
Autorzy:
Kulpa, J. S.
Misiurewicz, J.
Powiązania:
https://bibliotekanauki.pl/articles/226260.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
noise radar
noise SAR
waveform design
Opis:
Noise radar is a very promising technology offering advantages which cannot be achieved in classical radar systems. Unfortunately, it has also several disadvantages. One of the most significant is the masking effect, where strong objects raise the noise floor preventing detection of weak ones and significantly affecting dynamic range. In this article method of designing waveform with reduced noise floor is presented.
Źródło:
International Journal of Electronics and Telecommunications; 2011, 57, 3; 359-362
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Research on Impulsive Events in Railway Noise Generated During Passage Through a Railroad Switch
Autorzy:
Kukulski, B.
Wszołek, T.
Powiązania:
https://bibliotekanauki.pl/articles/176326.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
impulsive noise
railway noise measurements
impulsiveness
Opis:
This paper presents the result of research on the impulsive components of a railway noise generated during passage through a railroad switch compared with a typical rail noise and evaluation of this phenomenon with particular emphasis on impulsive sounds. The study includes the analysis of the source of impulsive components in the railway noise, the methodology of measurement and data analysis. Spectral analysis of typical fragments passing through a railroad switch is given together with a proposal of additional indicators to assess the noise. Authors propose three descriptors of the impulsive noise such as spectral centroid, kurtosis and impulsiveness, and show that these descriptors can be useful in assessment of the impulsive noise generated during trains’ crossing.
Źródło:
Archives of Acoustics; 2017, 42, 3; 441-447
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the Grid Sampling Method for Noise Mapping
Autorzy:
Gómez Escobar, V.
Barrigón Morillas, J. M.
Rey Gozalo, G
Vilchez-Gómez, R.
Carmona del Rio, J.
Méndez Sierra, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/176666.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
grid method
noise mapping
urban noise
Opis:
The grid method is the most widely used technique for measurement-based noise assessment, and indeed is part of the ISO 1996-2 standard. Nevertheless it has certain disadvantages. The present work is an analysis of the grid method for evaluating noise, firstly in the city of C´aceres and, secondly in two other smaller towns. Using as reference a 200 metre grid study, a study was made of the effect of varying the size and form of the grid on the city’s overall noise value, the percentage of data found to lie above some reference thresholds, and the noise value assigned to a certain zone of the city. The ISO 1996 recommendations of the necessity of new sampling points and the method’s predictive capacity for these new measurements were also analyzed.
Źródło:
Archives of Acoustics; 2012, 37, 4; 499-514
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł

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