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EN
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.
PL
W artykule przedstawiono wyniki badań dotyczących nowych rozwiązań niskostratnych przewodów przewidzianych do stosowania w napowietrznych liniach przesyłowych 400 kV. Omówiono materiałowe i technologiczne aspekty projektowania przewodów oraz zagadnienia mechaniczne i elektryczne dotyczące zarówno przewodów jak i linii. Dokonano wielokryterialnej analizy 80 projektów nowych typów przewodów. Zastosowanie w liniach przesyłowych nowych przewodów pozwoli na redukcję strat nawet o ponad 25%, w porównaniu z obecnie stosowanymi przewodami.
EN
The article presents results of studies carried out on the construction of new, low-loss conductors intended for use in overhead 400 kV transmission lines. We discuss the material and technological aspects of designing conductors and issues relating to mechanical and electrical conductors on the line. Developed and treated multi-criteria analysis of new types of conductors. We examined 80 projects of conductors. The use of the transmission lines with new low-loss conductors allows the reduction of energy losses in transmission lines by up to 25%, compared to the actually used conductors.
EN
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.
4
EN
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.
PL
W pracy zaprezentowano analizę rozkładu wartości wyników pomiarów i wskaźników zagrożeń hałasowych środowiska w wybranych długookresowych przedziałach czasowych. Wyniki i wnioski z tej analizy posłużą w następnych etapach badań do opracowania procedury pozwalającej na poprawny wybór lokalizacji punktu pomiarowego oraz okresu wykonywania pomiarów, zapewniający odpowiednio dokładne obliczenia wskaźnika LDWN na podstawie niekompletnego zestawu danych, nie obejmującego wszystkich dni w roku. Rezultaty obliczeń przedstawiono na bazie wyników ciągłego monitoringu hałasu drogowego prowadzonego w 4 punktach w głównych miastach województwa kujawsko pomorskiego, t.j. Bydgoszczy, Toruniu, Włocławku i Grudziądzu.
EN
The analysis of distribution of traffic noise measurements results performed with in the longtime chosen periods and calculated noise level descriptors are presented in the paper. Results and conclusions of the analysis will be used in next steps of there researches for developing a procedure which should allow to choose a measurement point localization and a measurement s period. The procedure should assure proper calculation of LDEN noise level descriptor for an incomplete set of measurements days. The calculations are made on basis of long period traffic noise monitoring results. The monitor mg was conducted in 4 points in the main towns of kujawsko-pomorskie voivodeship: Bydgoszcz, Toruń, Włocławek and Grudziądz The calculations result are presented.
PL
Dominującym źródłem hałasu kolejowego w przeważającym zakresie prędkości jest hałas toczenia wywołany drganiami kół i szyn spowodowanymi drganiami powstającymi na styku koło/szyna. Hałas toczenia ma charakter szerokopasmowy o narastającym udziale wyższych częstotliwości wraz ze wzrostem prędkości pociągów. Ale piski na krzywiznach są jednymi z najgłośniejszych i najbardziej dokuczliwych źródeł hałasu od linii kolejowych metra i tramwajów. Są one również spowodowane interakcją pomiędzy kotem a szyną, ale mają zupełnie inny charakter Są silnie tonalne i występują w ostrych łukach, a powodowane są drganiami kota w jednym z jego rezonansów. Można tu rozróżnić piski spowodowane ocieraniem bocznej i górnej części szyny, jak również piski od ocierania kołnierza. Podobnym zjawiskiem jest pisk hamulców, który jest emitowany w czasie hamowania.
EN
The most important source of noise from railways at most speeds is a rolling noise caused by wheel and rail vibrations induced at the wheel/rail contact. The rolling noise is fairly broad-band in nature, the relative importance of higher frequency components increasing as the train speed increases. But the curve squeal is one of the loudest and most disturbing noise sources from railways metros and tramways. It is also caused by interaction between wheel and rail but bas a quite different character. It is a strongly tonal noise occurring in sharp curves, being associated with vibration of the wheel in one of its resonances. It is also necessary to distinguish between the squeal caused by lateral creepage, top of rail squeal as well as flange squeal. A similar phenomenon is a brake squeal which is emitted during braking.
EN
This paper presents the work on the problem of the qualification of impulsive sounds for applying the adequate value of impulsive adjustment. Impulsive events must be included in the assessment of noise in Poland. There is no agreement for using the objective methods that could qualify impulsive sounds on the basis of the measurable physical characteristics of the impulses. Moreover, the arbitrary classification includes only a few specified sources. The paper presents a review of the methods and criteńa for the qualification of the impulses and provides the results of applying these methods on a certain impulsive noise source - the collision of train cars.
PL
W artykule zaprezentowano problem kwalifikacji dźwięków impulsowych w aspekcie wyznaczenia odpowiedniej wartości poprawki impulsowej. Uwzględnianie zjawisk impulsowych w ocenie hałasu środowiskowego jest w Polsce obowiązkowe. Jednakże nie ma jednej obiektywnej metody kwalifikacji impulsów na podstawie ich mierzalnych cech fizycznych. Co więcej, stosowane arbitralne metody obejmują jedynie kilka przypadków. W artykule dokonano przeglądu obowiązujących metod i kryteriów kwalifikacji dźwięków impulsowych, a także dokonano weryfikacji tych metod na przykładzie wybranego dźwięku impulsowego - zderzeń wagonów.
EN
The paper presents the current state of knowledge concerning the sources of noise generated by wind turbines, force measurement methodology, and assessment of noise onerousness in this type of installation, on the basis of a study concerning a wind farm with five REpower MM92 wind turbines and the electric power of 2 MW and the sound power level of 104.2 dB(A) each. Particular attention was focused on the often discussed problem of presence of infrasound generated by turbines and on the requirements of the applicable reference methodologies for the measurement of wind speed to 5 m/s, while the turbine reaches its full power at speeds above 10 m/s.
EN
Random nature of corona processes in UHV power lines and the accompanying noise is the reason that in practice the best determination of acoustic parameters, necessary for the noise evaluation, is obtained from the continuous monitoring procedure. However because of considerable fluctuations (both the useful signal part and the interfering components), careful selection of monitored parameters is necessary to enable a possibility of automatic determination of the parameters that are required for long-term evaluation of corona noise. In the present work a practical realization is shown for estimation of corona noise parameters, based on the data obtained from continuous monitoring stations, making use of the statistical spectra measurement and characteristic features of corona process acoustic signal. Selected results are presented from continuous monitoring of corona noise generated at a 400 kV power line, with special attention focused on definitions of the measured quantities, which enable automatic estimation of the basic factors required for noise evaluation. Accompanying monitoring of environmental conditions, including humidity, precipitation intensity and fog density, that are well correlated with the corona process intensity, which might definitely increase the filtration efficiency of environmental disturbances and on the other hand, it enables verification of calculation methods applied to corona noise. The paper also contains a description of practical approach to selection signal parameters of corona noise in continuous monitoring stations.
10
PL
W pracy pokazano model do obliczania poziomu mocy akustycznej jednostkowej długości przewodów fazowych w funkcji intensywności opadów, stanu technicznego oraz wysokości zawieszenia przewodów dla dowolnego układu geometrycznego linii WN. Przykładowe obliczenia rozkładu wskaźników długookresowych hałasu ulotu przeprowadzono w przekrojach poprzecznych oraz w postaci mapowej dla zróżnicowanych uwarunkowaniach terenowych.
EN
The paper shows a model to calculate the sound power level of unit length phase conductors as a function of rainfall intensity, the technical condition and the height of the suspended conductors for any geometric arrangement of power line. Sample calculations of the distribution of the long-term noise indicators were performed in cross sections and the form of maps in diverse terrain considerations.
PL
Ekrany instalowane są głównie w celu ograniczenia propagacji hałasu drogowego na tereny zamieszkałe. Aby były skuteczne, podczas ich projektowania i montażu należy wziąć pod uwagę szereg zjawisk akustycznych, z których najważniejsze jest zjawisko dyfrakcji.
EN
The paper refers to the issue of mistakes made during designing and realisation of noise barriers that influence their efficiency. The author describes important factors that have to be taken into consideration when designing and installing a noise barrier.
EN
In the spectrum of corona acoustic signal two characteristic components can be distinguished: (1) tonal components - higher harmonics of the network frequency and (2) noise component, observed in the frequency band extending above 1 kHz. On the other hand the total intensity of that signal is relatively low - up to 50dB at 15m distance from the outmost conductor - and it is strongly dependent on the environmental conditions. Thus the nature of that signal is essentially random. Because of the above-mentioned features, in practice the best evaluation method of the negative environmental impact is a continuous signal monitoring. Unfortunately for such a procedure some problems are encountered with automated extraction of the parameters (indicators) normally used for evaluation of the signal's acoustic annoyance, especially in intensified interference conditions. One of the more efficient methods of filtering out the random interference signals is the statistic spectrum measurement method. In this work a practical realization is described for estimation of corona noise indicators, making use of the statistic spectrum measurement. High efficiency of such an approach has been shown, especially in favorable weather conditions, when the acoustic signal of corona process is relatively low, while the random interference level may be intensified.
PL
Losowość zjawisk ulotowych w liniach elektroenergetycznych i towarzyszącego im hałasu sprawia, że w praktyce najlepszym sposobem oceny jego uciążliwości w środowisku jest monitoring ciągły. Wówczas jednak pojawiają się problemy z automatyczną ekstrakcją wskaźników stosowanych w ocenie uciążliwości akustycznej, zwłaszcza w warunkach podwyższonych zakłóceń. Jedną z bardziej wydajnych metod filtracji zakłóceń o charakterze losowym jest metoda pomiaru widma statystycznego. W pracy pokazano praktyczną realizację estymacji wskaźników hałasu ulotu na podstawie danych ze stacji monitoringu ciągłego z wykorzystaniem pomiaru widma statystycznego. Wykazano wysoką efektywność takiego podejścia zwłaszcza kiedy sygnał akustyczny ulotu jest relatywnie słaby, a poziom zakłóceń podwyższony.
EN
Random nature of corona phenomena in power lines and accompanying them audible noise cause that the best evaluation method of the negative environmental impact is a continuous signal monitoring. Unfortunately for such procedure some problems are encountered with automated extraction of the indicators normally used for evaluation of the corona audible annoyance, especially in intensified interference conditions. One of the more efficient methods of filtering out the random interference signals is the statistic spectrum measurement method. In this work a practical realization is described for estimation of corona noise indicators, making use of the statistic spectrum measurement. High efficiency of such an approach has been shown, especially when the acoustic signal of corona process is relatively low, whereas the random interference level may be intensified.
EN
Impulse sound events are characterised by ultra high pressures and low frequencies. Lower frequency sounds are generally less attenuated over a given distance in the atmosphere than higher frequencies. Thus, impulse sounds can be heard over greater distances and will be more affected by the environment. To calculate a longterm average immission level it is necessary to apply weighting factors like the probability of the occurrence of each weather condition during the relevant time period. This means that when measuring impulse noise at a long distance it is necessary to follow environmental parameters in many points along the way sound travels and also to have a database of sound transfer functions in the long term. The paper analyses the uncertainty of immission measurement results of impulse sound from cladding and destroying explosive materials. The influence of environmental conditions on the way sound travels is the focus of this paper.
EN
The paper deals with application of neural network techniques to recognition of typical damages of the transmission circuit elements in UHV power lines. The damage indicator is the acoustic signal generated by the corona effect, the intensity of which increases as a result of damage or contamination of the conductor surface. The primary difficulty in the diagnostic process is the necessity to distinguish between the signals generated by the surface damages and contaminations. The problem can not be solved neither by the analysis of RF interference signal nor by the classical methods of the acoustic signal analysis. Particular attention has been focused on the parametrization of the acoustic signal of corona effect and selection of distinctive features, which could be useful in distinguishment of the origins of the increased corona effect in dry conductor surface conditions. For that task the aggregation analysis has been applied, in particular the possibilities offered by "Statistica"Ž software package. The data used in the analysis has been obtained from laboratory studies in Institute of Power Engineering in Warsaw, where typical surface damages and contaminations of the transmission line elements have been simulated.
EN
The subject of the present paper is a proposition of methodology for construction of systems for acoustic signals recognition, based on utilization of artificial intelligence methods and techniques. In the paper an attempt is made to create a new approach to construction of a diagnostic system, capable of automated assessment of the condition of technological processes. This is a concept of replacing the simple signal recognition process by more advanced method of its analysis, called a process of automated understanding of the acoustic signal. The method is based on utilization of an internal model for generation of the signal considered and it is directed towards the structure analysis of the investigated sound signal. Thus the research is oriented on the construction of systems based on analysis of objectively registered signals, generated by the objects being under diagnostic evaluation. The present considerations have been restricted to systems performing automated assessment of a selected class of vibroacoustic signals, and dedicated to diagnosis of technical and medical objects.
17
Content available remote Analiza wpływu urządzeń wiertniczych na klimat wibroakustyczny środowiska
PL
W pracy zamieszczono wyniki badań parametrów wibroakustycznych i ich emisji do środowiska dla wybranych urządzeń wiertniczych. Badaniami objęto urządzenia wiertnicze SKYTOP TR-80, KREMCO K.-900, IRI-750/CABOT, IRI E 1200 o zróżnicowanych parametrach technicznych i technologicznych. Uzyskane wyniki wykazały, że poszczególne urządzenia wiertnicze w zróżnicowany sposób oddziałują na środowisko. Świadczą o tym wyraźnie kierunkowe charakterystyki akustyczne, a także wahania poziomu emitowanego hałasu w zależności od cyklu roboczego. Wykazano, że możliwa jest optymalizacja ustawienia urządzeń wiertni oraz obiektów towarzyszących, a także i cyklu robót, pozwalająca na redukcję oddziaływań akustycznych na środowisko bez dodatkowych zabezpieczeń przeciwhałasowych.
EN
The results of vibroacoustic and emission tests for selected drilling rigs (SKYTOP TR-80, KREMCO K-900, IRI750/ CABOT. IRI E 1200 - varying in technical and technology parameters) are presented in the paper. The individual rigs differed in their environmental impact. They have distinct directional acoustic characteristics, and the level of emitted noise depends on the working cycle. It was shown that the setting of the rigs and the accompanying objects could be optimised, and the working cycle so adjusted as to reduce the acoustic impact on the environment without any auxiliary noise protections.
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