Articoli di riviste: "Aircraft cabins Noise Measurement"

1

Hughes, Stanley T., e Jefferson Koonce. "Cabin Noise Levels in Single Engine General Aviation Aircraft". Proceedings of the Human Factors Society Annual Meeting 30, n. 14 (settembre 1986): 1381–85. http://dx.doi.org/10.1177/154193128603001408.

Testo completo

Abstract (sommario):

Sound level measurements were made on several of the most popular general aviation aircraft produced. Measurements were taken at various flight milestones such as; run up, taxi, climb, cruise power and descent. For each of the aircraft a time weighted mission sound level was obtained, using three different mission scenarios, varying only in flight time. For each of the three scenarios, and for all aircraft, the time weighted noise values obtained were an or exceeded the 85 dBA limit recommended by NIOSH. The results of this study indicate that a substantial percentage of general aviation pilots will show some loss of hearing due to the high noise levels present in their cabins. Recommendations are made for protection of occupants of general aviation aircraft.

Gli stili APA, Harvard, Vancouver, ISO e altri

2

Kong, Qing Fu, Yu Liang Dai, Shi Jian Zhu e Jia Ming Wu. "Experimental Study on an Active Noise Control System for Turboprop Driven Aircraft". Applied Mechanics and Materials 333-335 (luglio 2013): 2142–45. http://dx.doi.org/10.4028/www.scientific.net/amm.333-335.2142.

Testo completo

Abstract (sommario):

In order to find a solution to the control of low frequency noise in the cabin of turboprop driven aircraft, an experimental active noise control (ANC) system is introduced in the paper, which consists of vibroacoustic field analogue subsystem, acoustic field measurement subsystem and acoustic barrier exciter subsystem. Effects of both different spaces between the primary sound source and secondary sound source of the ANC system and different frequency noises on noise-reduction result are investigated based on the experimental platform. Results of the experiment show a significant potential of the ANC method for the control of low frequency noise in the cabin of turboprop driven aircraft.

Gli stili APA, Harvard, Vancouver, ISO e altri

3

Joshi, Pankaj, Frank Khelfa, Hendrik Lehmkuhl, Patrick Cordes, Patrick Naujoks, Thorsten Scharowsky e Kay Kochan. "Design, development and testing of digital MEMS pressure sensor array for full-scale vibroacoustic measurements". INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, n. 2 (1 agosto 2021): 4343–54. http://dx.doi.org/10.3397/in-2021-2671.

Testo completo

Abstract (sommario):

This manuscript addresses design, development, and application of micro-electro-mechanical systems (MEMS) based digital pressure sensor array for vibroacoustic measurements. These vibroacoustic measurements were conducted on a A320 type single aisle aircraft demonstrator subjected to broadband as well as tonal excitations. Cabin noise levels were measured with both condenser microphones as well as digital MEMS pressure sensor array. The measured cabin noise shows strong qualitative as well as quantitative agreement between both type of measurement devises for full scale cabin noise measurements inside an aircraft demonstrator. The observed strong agreement is valid for both single wall (fuselage with thermal insulation) and double wall (fuselage with thermal insulation and trim panel) cabin noise measurements. Such strong agreement within 1.0 dB tolerance is significantly motivating for further development of reliable but low-cost MEMS based measurement devises and corresponding efficient data post-processing algorithms for full scale vibroacoustic measurements in general. Additionally, it is also demonstrated that the large number of MEMS based digital pressure sensors can be used in areas where the physical space constraints are high. This demonstration shows strong potential to derive additional vibroacoustic indicator for the development and the testing of future noise control solutions in a non-traditional way.

Gli stili APA, Harvard, Vancouver, ISO e altri

4

Spehr, Carsten, Daniel Ernst e Hans-Georg Raumer. "MEMS microphone intensity array for cabin noise measurements". INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, n. 3 (1 agosto 2021): 3023–34. http://dx.doi.org/10.3397/in-2021-2288.

Testo completo

Abstract (sommario):

Aircraft cabin noise measurements in flight are used toto quantify the noise level, and to identify the entry point of acoustic energy into the cabin. Sound intensity probes are the state-of-the-art measurement technique for this task. During measurements, additional sound absorbing material is used to ease the rather harsh acoustic measurement environment inside the cabin. In order to decrease the expensive in-flight measurement time, an intensity array approach was chosen. This intensity probe consists of 512 MEMS-Microphones. Depending on the frequency, these microphones can be combined as an array of hundreds of 3D- intensity probes. The acoustic velocity is estimated using a high order 3D finite difference stencil. At low frequencies, a larger spacing is used to reduce the requirement of accurate phase match of the microphone sensors. Measurements were conducted in the ground-based Dornier 728 cabin noise simulation as well as in-flight.

Gli stili APA, Harvard, Vancouver, ISO e altri

5

PAČAIOVÁ, Hana, Marianna TOMAŠKOVÁ, Michaela BALÁŽIKOVÁ e Jozef KRAJŇÁK. "Analysis of air-traffic threats". Scientific Journal of Silesian University of Technology. Series Transport 110 (1 marzo 2021): 143–55. http://dx.doi.org/10.20858/sjsutst.2021.110.12.

Testo completo

Abstract (sommario):

Globally, air transport has seen a greater increase in recent years. This manuscript is divided into three parts for analysing the negative effects of aviation. The first part is focused on the identification of sources of aircraft noise. While the second part of this article describes the basic principles of the construction and operation of an aircraft jet engine concerning the gaseous emissions produced by such an engine (Third part missing?). The main benefit of this article is the evaluation of the reliability of the human factor because the human factor is an integral part of technical systems and processes. Reliability assessment was performed using the TESEO method. The ergonomic parameter, that is, the cabin noise, was quantified in the given method. The measurement was performed on two types of aircraft, namely in the cabin of a transport jet aircraft and in the cabin of asmall transport aircraft equipped with turboprop engines.

Gli stili APA, Harvard, Vancouver, ISO e altri

6

Schüür, Jens, Lukas Oppermann, Achim Enders, Rafael R. Nunes e Carl-Henrik Oertel. "Emission analysis of large number of various passenger electronic devices in aircraft". Advances in Radio Science 14 (28 settembre 2016): 129–37. http://dx.doi.org/10.5194/ars-14-129-2016.

Testo completo

Abstract (sommario):

Abstract. The ever increasing use of PEDs (passenger or portable electronic devices) has put pressure on the aircraft industry as well as operators and administrations to reevaluate established restrictions in PED-use on airplanes in the last years. Any electronic device could cause electromagnetic interference to the electronics of the airplane, especially interference at receiving antennas of sensitive wireless navigation and communication (NAV/COM) systems. This paper presents a measurement campaign in an Airbus A320. 69 test passengers were asked to actively use a combination of about 150 electronic devices including many attached cables, preferentially with a high data load on their buses, to provoke maximal emissions. These emissions were analysed within the cabin as well as at the inputs of aircraft receiving antennas outside of the fuselage. The emissions of the electronic devices as well as the background noise are time-variant, so just comparing only one reference and one transmission measurement is not sufficient. Repeated measurements of both cases lead to a more reliable first analysis. Additional measurements of the absolute received power at the antennas of the airplane allow a good estimation of the real interference potential to aircraft NAV/COM systems. Although there were many measured emissions within the cabin, there were no disturbance signals detectable at the aircraft antennas.

Gli stili APA, Harvard, Vancouver, ISO e altri

7

Zettel, Sebastian, René Winter, Marco Norambuena, Marc Böswald, Martin Richter e Gregor Tanner. "Finite element method and dynamical energy analysis in vibro-acoustics - A comparative study". INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, n. 5 (1 agosto 2021): 1712–22. http://dx.doi.org/10.3397/in-2021-1906.

Testo completo

Abstract (sommario):

Future aircraft concepts utilizing innovative lightweight structures and novel propulsion concepts are a necessity for long term sustainable air travel. These concepts pose new challenges for the vibro-acoustic assessment of cabin structures and the associated noise impact on passengers. Finite Element (FE) models derived from aircraft pre-design data are not optimized for use in acoustic analyses, i.e. the mesh is too coarse to provide meaningful results while setting up Statistical Energy Analysis models for this specific purpose is adding another time-consuming step. A possible alternative, Discrete Energy Analysis (DEA), is evaluated. This method allows to calculate the acoustic behavior of thin-walled structures in higher frequency ranges simply using existing FE meshes. In this paper an experimental lightweight aluminum structure and its respective FE model is investigated for a frequency range up to 5000 Hz. A comparison in terms of vibrational energy between DEA, FE and measurement results are presented. Finally, a lower-bound frequency range is identified in which DEA and FEM correlate and thus allow a substitution for further simulations at higher frequencies.

Gli stili APA, Harvard, Vancouver, ISO e altri

8

Ross, Colin F. "Active noise control in aircraft cabins". Journal of the Acoustical Society of America 105, n. 2 (febbraio 1999): 1243. http://dx.doi.org/10.1121/1.425969.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

9

Kloss, Corinna, Vicheith Tan, J. Brian Leen, Garrett L. Madsen, Aaron Gardner, Xu Du, Thomas Kulessa et al. "Airborne Mid-Infrared Cavity enhanced Absorption spectrometer (AMICA)". Atmospheric Measurement Techniques 14, n. 8 (2 agosto 2021): 5271–97. http://dx.doi.org/10.5194/amt-14-5271-2021.

Testo completo

Abstract (sommario):

Abstract. We describe the Airborne Mid-Infrared Cavity enhanced Absorption spectrometer (AMICA) designed to measure trace gases in situ on research aircraft using Off-Axis Integrated Cavity Output Spectroscopy (OA-ICOS). AMICA contains two largely independent and exchangeable OA-ICOS arrangements, allowing for the simultaneous measurement of multiple substances in different infrared wavelength windows tailored to scientific questions related to a particular flight mission. Three OA-ICOS setups have been implemented with the aim to measure OCS, CO2, CO, and H2O at 2050 cm−1; O3, NH3, and CO2 at 1034 cm−1; and HCN, C2H2, and N2O at 3331 cm−1. The 2050 cm−1 setup has been characterized in the laboratory and successfully used for atmospheric measurements during two campaigns with the research aircraft M55 Geophysica and one with the German HALO (High Altitude and Long Range Research Aircraft). For OCS and CO, data for scientific use have been produced with 5 % accuracy (15 % for CO below 60 ppb, due to additional uncertainties introduced by dilution of the standard) at typical atmospheric mixing ratios and laboratory-measured 1σ precision of 30 ppt for OCS and 3 ppb for CO at 0.5 Hz time resolution. For CO2, high absorption at atmospheric mixing ratios leads to saturation effects that limit sensitivity and complicate the spectral analysis, resulting in too large uncertainties for scientific use. For H2O, absorption is too weak to be measured at mixing ratios below 100 ppm. By further reducing electrical noise and improving the treatment of the baseline in the spectral retrieval, we hope to improve precision for OCS and CO, resolve the issues inhibiting useful CO2 measurements, and lower the detection limit for H2O. The 1035 and 3331 cm−1 arrangements have only partially been characterized and are still in development. Although both setups have been flown and recorded infrared spectra during field campaigns, no data for scientific use have yet been produced due to unresolved deviations of the retrieved mixing ratios to known standards (O3) or insufficient sensitivity (NH3, HCN, C2H2, N2O). The ∼100 kg instrument with a typical in-flight power consumption of about 500 VA is dimensioned to fit into one 19 in. rack typically used for deployment inside the aircraft cabin. Its rugged design and a pressurized and temperature-stabilized compartment containing the sensitive optical and electronic hardware also allow for deployment in payload bays outside the pressurized cabin even at high altitudes of 20 km. A sample flow system with two parallel proportional solenoid valves of different size orifices allows for precise regulation of cavity pressure over the wide range of inlet port pressures encountered between the ground and maximum flight altitudes. Sample flow of the order of 1 SLM (standard litre per minute) maintained by an exhaust-side pump limits the useful time resolution to about 2.5 s (corresponding to the average cavity flush time), equivalent to 500 m distance at a typical aircraft speed of 200 m s−1.

Gli stili APA, Harvard, Vancouver, ISO e altri

10

Takahashi, Kosaku, Hirotaka Monzen, Toshihiro Yamaoka, Koji Kusumoto, Kazuhiro Bansaku, Jyunichi Kimoto, Akira Isoe, Yasuo Hirose, Tomio Sanda e Yuji Matsuzaki. "Noise and vibration reduction technology in aircraft cabins". Advanced Composite Materials 13, n. 1 (gennaio 2004): 67–80. http://dx.doi.org/10.1163/1568551041408787.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

11

Rady de Almeida Junior, Jorge, Magali Andreia Rossi, Mário Corrêa, Javier Francisco Ramirez‐Fernandez, Vicente Carlos Poli e Genivaldo José de Menezes. "Analysis of noise in aircraft cabins through the VHF channel". Aircraft Engineering and Aerospace Technology 84, n. 4 (29 giugno 2012): 213–20. http://dx.doi.org/10.1108/00022661211237737.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

12

Alvelid, M. "Nonlinear Fluid-Structure Interaction in Propeller Aircraft Cabins". Journal of Vibration and Acoustics 119, n. 3 (1 luglio 1997): 363–73. http://dx.doi.org/10.1115/1.2889732.

Testo completo

Abstract (sommario):

A procedure for studying the acoustic superharmonic response in propeller aircraft cabins subject to stationary single frequency load excitation is proposed. The harmonic balance method is used to solve the nonlinear fluid-structure interaction multi-degree-of-freedom problem at hand. In the problem studied, the structure is nonlinear while the fluid remains linear. In the solution method proposed, generalised coordinates of the assumed series expansion for the displacements are used as unknowns. Two examples, simulating an aircraft structure with a fluid cavity, are examined. The present calculations show that in a lightly damped one-dimensional system with cubic stiffness, the noise levels from the superharmonic resonance may be slightly lower than those resulting from the fundamental frequency. For a typical model of a cross-section of an aircraft cabin, it is shown that nonlinear damping in spacing material will result in a considerable influence of the response in the third tone. For the one-dimensional system, good agreement is obtained with results from parallel nonlinear analyses where the discretized system of inertia equations is solved employing explicit time integration. For the multi-degree-of-freedom system modelling the aircraft cabin, a comparison of results between the harmonic balance method and the explicit time integration of a corresponding FE model indicated a partial agreement of the two. However, several different solutions may exist to a nonlinear equation, which make the comparison uncertain.

Gli stili APA, Harvard, Vancouver, ISO e altri

13

Gao, Jie, e Ning Qiang. "Multi-objective Optimized Design for Intermediate-Frequency Noise Reduction in Aircraft Cabins". Wireless Personal Communications 102, n. 4 (6 febbraio 2018): 3737–47. http://dx.doi.org/10.1007/s11277-018-5405-2.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

14

Marant, Vincent, Antonio Reig Fabado, Juan Luís Aguilera De Maya e José Christian Donayre Ramírez. "Passive and active designs for noise and vibrations reduction in aircraft cabins". Journal of the Acoustical Society of America 123, n. 5 (maggio 2008): 3525. http://dx.doi.org/10.1121/1.2934463.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

15

Tandon, N. "Aircraft Noise". Noise & Vibration Worldwide 34, n. 4 (aprile 2003): 11–14. http://dx.doi.org/10.1260/095745603321832471.

Testo completo

Abstract (sommario):

Various noise measurement parameters/indices used to define aircraft and airport noise are explained. The noise zone limits used around airports in some countries are given. Noise prediction software can be used to generate noise contours around airports. New aircraft noise certification standards have been developed to encourage control of aircraft noise at source. Aircraft noise can also be reduced if noise abatement landing and take-off procedures are followed.

Gli stili APA, Harvard, Vancouver, ISO e altri

16

Bukhtiyarov, I. V., M. F. Vilk, V. D. Glukhovskiy, N. N. Kurierov, V. A. Kaptsov, V. B. Pankova e L. V. Prokopenko. "Updating the assessment methodology of the acoustic load of flight crew members in the cabins of civil aviation aircraft". Russian Journal of Occupational Health and Industrial Ecology, n. 2 (21 febbraio 2020): 100–116. http://dx.doi.org/10.31089/1026-9428-2020-60-2-100-116.

Testo completo

Abstract (sommario):

The article discusses the issues of adjustment, developed in 2007 and supplemented in 2009, of the methodology for evaluating the equivalent level of cabin noise of civil aviation aircraft in Russia. The relevance of the problem is due to high levels of professional hearing loss among the aircrew members of the air force, which is directly related to the lack of unified and competent approaches to assessing the acoustic load on the hearing organ of the aircrew members. The updated methodology contains full-fledged data on noise levels in modern domestic and foreign airliners, data on certification of acoustic efficiency of aircraft accessories, a direct algorithm and formulas for calculating the noise load for the selected periods of flight operation.

Gli stili APA, Harvard, Vancouver, ISO e altri

17

Igarashi, Juichi, e Ichiro Yamada. "Aircraft noise monitoring by short-term measurement." Journal of the Acoustical Society of Japan (E) 10, n. 4 (1989): 197–204. http://dx.doi.org/10.1250/ast.10.197.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

18

Snell, Andrew, e Darren Wallis. "The Flight Path of Aircraft Noise Measurement". Measurement and Control 34, n. 3 (aprile 2001): 69–71. http://dx.doi.org/10.1177/002029400103400302.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

19

Tavossi, Hasson M. "Active and passive techniques for a cost-effective noise reduction in the interior of aircraft cabins". Journal of the Acoustical Society of America 138, n. 3 (settembre 2015): 1941. http://dx.doi.org/10.1121/1.4934131.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

20

Fang, Zhaosong, Hong Liu, Baizhan Li e Andrew Baldwin. "Investigation of thermal comfort and the nozzle usage behaviour in aircraft cabins". Indoor and Built Environment 28, n. 1 (10 novembre 2017): 118–31. http://dx.doi.org/10.1177/1420326x17739446.

Testo completo

Abstract (sommario):

In order to understand passengers’ demand for thermal comfort in aircraft cabins, we carried out a measurement of thermal environment parameters and thermal comfort field survey in an aircraft cabin under cruising at altitude in both summer and winter. The results showed that the air temperature studied was always kept within the range of 25℃ to 28℃ and the relative humidity was maintained within the range of 20% to 35%. The Mean Thermal Sensation Vote (MTSV) of passengers’ back and feet was higher than other local body parts, with lower air movement sensation. The MTSV of passengers in winter was higher than that in summer. Due to the muggy thermal environment, more than 60% of passengers advocated that it was necessary to utilize the personal ventilation system. In their usage of the personal ventilation nozzle, more than half of these passengers chose to cool upper body parts, only a minimum number of passengers opened the nozzle to direct airflow to their head. Therefore, we concluded that the position of the personal ventilation nozzle should be as close to the upper body part of a passenger’s body as possible, making it more convenient and effective to regulate passengers’ thermal comfort.

Gli stili APA, Harvard, Vancouver, ISO e altri

21

Stansfeld, S. A., C. R. Clark, G. Turpin, L. M. Jenkins e A. Tarnopolsky. "Sensitivity to noise in a community sample: II. Measurement of psychophysiological indices". Psychological Medicine 15, n. 2 (maggio 1985): 255–63. http://dx.doi.org/10.1017/s0033291700023539.

Testo completo

Abstract (sommario):

SynopsisA sample of 77 women of high and low noise sensitivity in 1977, living in areas of high and low exposure to aircraft noise, were interviewed in the community in 1980. High, intermediate and low noise sensitive women were compared, using measures of blood pressure, heart rate, skin conductance, hearing threshold, uncomfortable loudness level and magnitude estimation of six tones. These physiological measures did not clearly distinguish different noise sensitivity groups, except that highly noise sensitive women had a consistently slower heart rate. Noise sensitivity was not related to auditory threshold. In the high aircraft noise area there were significantly more skin conductance responses than in the low aircraft noise area, irrespective of noise sensitivity. This may be the result of chronic exposure to high aircraft noise.

Gli stili APA, Harvard, Vancouver, ISO e altri

22

Kroesen, Maarten, e Dirk Schreckenberg. "A measurement model for general noise reaction in response to aircraft noise". Journal of the Acoustical Society of America 129, n. 1 (gennaio 2011): 200–210. http://dx.doi.org/10.1121/1.3514542.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

23

McKinley, Richard L., Alan T. Wall, Theo A. van Veen e Jaap van't Hof. "Measurement methods for high-performance jet aircraft noise inside a hardened aircraft shelter". Journal of the Acoustical Society of America 142, n. 4 (ottobre 2017): 2514. http://dx.doi.org/10.1121/1.5014180.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

24

Shivashankara, Belur N., e Gene W. Stubbs. "Ground plane microphone for measurement of aircraft flyover noise". Journal of Aircraft 24, n. 11 (novembre 1987): 751–58. http://dx.doi.org/10.2514/3.45517.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

25

Li, Yong, Malcolm Smith e Xin Zhang. "Measurement and control of aircraft landing gear broadband noise". Aerospace Science and Technology 23, n. 1 (dicembre 2012): 213–23. http://dx.doi.org/10.1016/j.ast.2011.07.009.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

26

Bukhtiyarov, Igor V., Nicolay N. Courierov, Alla V. Lagutina, Lyudmila V. Prokopenko e Evgeny V. Zibarev. "Aircraft noise in residential areas, problems of measuring and evaluation". Hygiene and sanitation 99, n. 10 (30 novembre 2020): 1042–48. http://dx.doi.org/10.47470/0016-9900-2020-99-10-1042-1048.

Testo completo

Abstract (sommario):

The intensity of civil aircraft flights elevates with the increase in the number of passenger and cargo transportation by air. Aircraft noise in the residential area near airports grows up too despite the use of low-noise aircraft models by airlines. This causes an augmentation in the number of complaints of the population in these areas. The Russian Federation’s normative and methodological documents requirements in force relating to measurements and assessment of noise in residential areas, including «aircraft noise», were analyzed. Their requirements in terms of measuring and assessing noise in residential areas, including “aircraft noise”, testifies to the insufficiency and ambiguity of these requirements. The main disadvantages are the lack of a clear definition of which sound event is considered «aircraft noise» and the lack of requirements for the duration of the reference time interval of noise measurement. The foreign experience of measuring and evaluating aircraft noise, as well as the effects of such noise on the population, are considered. This made it possible to determine the necessary and sufficient parameters for noise control in residential areas, including «aircraft noise». There were proposed both a definition of «aircraft noise» and the necessary parameters for its assessment. The necessary duration of the reference time interval for the measurement of normalized parameters was justified. Method for the normalized noise parameters in residential areas measurement using the chronograms of sound levels A was proposed. The technical implementation of such a method is presented. Proposed a definition of «aircraft noise» and measuring normalized parameters in the 15-minute reference time interval for inclusion in regulatory and methodological documents will help to eliminate ambiguity in measurements and noise assessment in residential areas.

Gli stili APA, Harvard, Vancouver, ISO e altri

27

Dekoninck, Luc. "Detecting and Correlating Aircraft Noise Events below Ambient Noise Levels Using OpenSky Tracking Data". Proceedings 59, n. 1 (3 dicembre 2020): 13. http://dx.doi.org/10.3390/proceedings2020059013.

Testo completo

Abstract (sommario):

Noise annoyance due to aircraft operations extends well beyond the 55 Lden noise contours as calculated according to the Environmental Noise Directive (END). Noise mapping beyond these contours will improve the understanding of the perception, annoyance and health impact of aircraft operations. OpenSky data can provide the spatial data to create an aircraft noise exposure map for lower exposure levels. This work presents the first step of region-wide noise exposure methodology based on open source data: detecting low LAmax aircraft events in ambient noise using spectral noise measurements and correlating the detected noise events to the matching flights retrieved from the OpenSky database. In ISO 20906:2009, the specifications of noise monitoring near airports is standardized, using LAeq,1sec values for event detection. This limits the detection potential due to masking by other noise sources in areas with low maximum levels of aircraft noise and in areas with medium maximum levels of high ambient exposure areas. The typical lower detection limit in airport-based monitoring systems ranges from 55 to 60 LAeq,max, depending on the ambient levels. Using a detection algorithm sensitive to third-octave band levels, aircrafts can be detected down to 40 LAmax in ambient noise levels of a similar magnitude. The measurement approach is opportunistic: aircraft events are detected in available environmental noise data series registered for other applications (e.g., road noise, industrial noise, etc.). Most of the measurement locations are not identified as high-exposure areas for aircraft noise. Detection settings can vary to match ambient noise levels to improve the correlation success.

Gli stili APA, Harvard, Vancouver, ISO e altri

28

Vidović, Andrija, Igor Štimac e Robert Zečević-Tadić. "Aircraft Noise Monitoring in Function of Flight Safety and Aircraft Model Determination". Journal of Advanced Transportation 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/2850860.

Testo completo

Abstract (sommario):

This paper presents the research of noise level monitoring at the Zagreb Airport Ltd. The purpose of this paper is to show how the aircraft noise sources can be used as a tool for aircraft detection and for increasing flight safety. The noise measurement was made at the Zagreb Airport by using its professional noise monitoring system. The research has led to new findings, such as determining the aircraft model by measuring the noise level generated by an aircraft during final approach based on its frequency spectrum, as the connectivity from the airport’s side to the radar data was unavailable (only ATC). In addition, it is possible to determine the aircraft altitude and, perhaps most significantly, the increase of flight safety through the detection of potential failures on the aircraft structure and/or engine during the overflight of a noise monitoring terminal.

Gli stili APA, Harvard, Vancouver, ISO e altri

29

Cieślak, Sławomir, e Wiesław Krzymień. "Drivetrain Noise of The Gyroplane I-28". Transactions on Aerospace Research 2018, n. 1 (1 marzo 2018): 7–16. http://dx.doi.org/10.2478/tar-2018-0001.

Testo completo

Abstract (sommario):

Abstract Gyroplanes, as ultralight aircraft, are popular transport vehicles recently. Ultralight aircraft flights take place at a low altitude – their noise is not without effect on people and nature. The localization of the sources of noise and a possibility to decrease the noise of an gyroplane are described in this paper. The rules of design and exploitation of gyroplanes do not define the limits of emitted noise. Gyroplanes are not noisy aircraft vehicles but for their silencing the knowledge about the sources and frequency range of noise is necessary. The goal of the conducted measurement was to determine the gyro-plane noise properties and the noise measurement methods. The evaluation of the noise sources was made by acoustic beamforming and the directional emission with single microphones at various engine speeds. The supplement of these tests should be the rotor noise measurement but that investigation should be performed on a special stand, on which the rotor propulsion noise would not disturb the measurement.

Gli stili APA, Harvard, Vancouver, ISO e altri

30

Schwarzbach, Paul, Julia Engelbrecht, Albrecht Michler, Michael Schultz e Oliver Michler. "Evaluation of Technology-Supported Distance Measuring to Ensure Safe Aircraft Boarding during COVID-19 Pandemic". Sustainability 12, n. 20 (21 ottobre 2020): 8724. http://dx.doi.org/10.3390/su12208724.

Testo completo

Abstract (sommario):

With the rise of COVID-19, the sustainability of air transport is a major challenge, as there is limited space in aircraft cabins, resulting in a higher risk of virus transmission. In order to detect possible chains of infection, technology-supported apps are used for social distancing. These COVID-19 applications are based on the display of the received signal strength for distance estimation, which is strongly influenced by the spreading environment due to the signal multipath reception. Therefore, we evaluate the applicability of technology-based social distancing methods in an aircraft cabin environment using a radio propagation simulation based on a three-dimensional aircraft model. We demonstrate the susceptibility to errors of the conventional COVID-19 distance estimation, which can lead to large errors in the determination of distances and to the impracticability of traditional tracing approaches during passenger boarding/deboarding. In the context of the future connected cabin, a robust distance measurement must be implemented to ensure safe travel. Finally, our results can be transferred to similar fields of application, e.g., trains or public transport.

Gli stili APA, Harvard, Vancouver, ISO e altri

31

Yan, Guo Hua, Wen Qian Song e Shi Qi Liu. "Test Noise Procedures for Transport Category and Turbojet Airplanes". Applied Mechanics and Materials 602-605 (agosto 2014): 2473–77. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.2473.

Testo completo

Abstract (sommario):

Aircraft noise is the chief source of the airport and its peripheral areas. CCAR imposes restriction on specific categories of aircraft and requires more strict measurements of the noise. More scientific measurement method is required to meet the progressively tighter certification standards. Test noise procedures for transport category and turbojet airplanes are analyzed in this paper. The main aspects involved are: test sit requirements, aircraft flight path guidance, aircraft position determination, take off tests, lateral tests and approach tests.

Gli stili APA, Harvard, Vancouver, ISO e altri

32

Woo, Jeong Ha, e Byung Chan Lee. "A Noise Prediction Method on the Movement Measuring Points at Measurement for Aircraft Noise". Transactions of the Korean Society for Noise and Vibration Engineering 25, n. 12 (20 dicembre 2015): 901–6. http://dx.doi.org/10.5050/ksnve.2015.25.12.901.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

33

Genescà, Meritxell, Jordi Romeu, Robert Arcos e Sara Martín. "Measurement of aircraft noise in a high background noise environment using a microphone array". Transportation Research Part D: Transport and Environment 18 (gennaio 2013): 70–77. http://dx.doi.org/10.1016/j.trd.2012.09.002.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

34

Morinaga, Makoto, Takanori Matsui, Sonoko Kuwano e Seiichiro Namba. "An experiment on the feeling of separation when multiple aircraft noises are overlapped". INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, n. 4 (1 agosto 2021): 2058–63. http://dx.doi.org/10.3397/in-2021-2041.

Testo completo

Abstract (sommario):

In order to calculate the A-weighted single event sound exposure level () of aircraft noise, the following method is described in the manual for aircraft noise measurement in Japan. Firstly a time-section, which is the range between two points where the noise level is 10 dB lower than the maximum noise level (), should be identified, and secondly the energy within the section is integrated. This method can easily be applied to the single event noises. When multiple aircraft noises are overlapped simultaneously, there are cases where cannot be calculated adequately by this method. In such cases, it is required to record the number of aircraft noises in the field measurements. However, even in the case of manned measurement, it is not easy to separate sound sources just by listening to the sound. A pilot study of the psychoacoustic experiment was conducted using the stimuli where multiple aircraft noises were overlapped in order to find what condition is needed so that multiple aircraft noises were separately perceived. It was suggested that a considerable time interval was needed so that people felt the separation between aircraft noises only with auditory information.

Gli stili APA, Harvard, Vancouver, ISO e altri

35

Jategaonkar, R. V., e E. Plaetschke. "Algorithms for aircraft parameter estimation accounting for process and measurement noise". Journal of Aircraft 26, n. 4 (aprile 1989): 360–72. http://dx.doi.org/10.2514/3.45769.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

36

Ncube, France, Esper Jacobeth Ncube e Kuku Voyi. "Bioaerosols, Noise, and Ultraviolet Radiation Exposures for Municipal Solid Waste Handlers". Journal of Environmental and Public Health 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/3081638.

Testo completo

Abstract (sommario):

Few studies have investigated the occupational hazards of municipal solid waste workers, particularly in developing countries. Resultantly these workers are currently exposed to unknown and unabated occupational hazards that may endanger their health. We determined municipal solid waste workers’ work related hazards and associated adverse health endpoints. A multifaceted approach was utilised comprising bioaerosols sampling, occupational noise, thermal conditions measurement, and field based waste compositional analysis. Results from our current study showed highest exposure concentrations for Gram-negative bacteria (6.8 × 103 cfu/m3) and fungi (12.8 × 103 cfu/m3), in the truck cabins. Significant proportions of toxic, infectious, and surgical waste were observed. Conclusively, municipal solid waste workers are exposed to diverse work related risks requiring urgent sound interventions. A framework for assessing occupational risks of these workers must prioritize performance of exposure assessment with regard to the physical, biological, and chemical hazards of the job.

Gli stili APA, Harvard, Vancouver, ISO e altri

37

Chen, Tao, Hong Hou, Zhi Fei Chen e Cheng Kun Jiang. "Measurement of ARJ21 Aircraft Landing Gear Noise Using Array Signal Processing Technology". Advanced Materials Research 588-589 (novembre 2012): 747–50. http://dx.doi.org/10.4028/www.scientific.net/amr.588-589.747.

Testo completo

Abstract (sommario):

Flyover noise measurements were conducted on an aircraft ARJ21 aiming at landing gear noise prediction schemes. The analysis is based on acoustic dedopplerized spectra and localization maps was calculated with the pressure signals of a acoustic phased array with 30 microphones. The acoustic phased array is a spatially distributed set of microphones which simultaneously sample the acoustic field. The doppler shifts was removed using linear interpolation.By appropriately time delaying the output of individual microphones, the origin and level of noise source(the landing gear) can potentially be determined. The success of this approach depends largely on the phased array design, and the array data processing method. This paper focuses on the two areas.

Gli stili APA, Harvard, Vancouver, ISO e altri

38

Nakazawa, Toshiyasu, e Naoaki Shinohara. "Study on aircraft noise directivity of behind the start of takeoff roll". INTER-NOISE and NOISE-CON Congress and Conference Proceedings 263, n. 3 (1 agosto 2021): 3202–8. http://dx.doi.org/10.3397/in-2021-2330.

Testo completo

Abstract (sommario):

This paper discusses aircraft noise directivity behind the start of takeoff roll. Aircraft noise has the radiation directivity because of aircraft engine mount position and the engine noise directivity. Thus, lateral noise directivity correction is recommended in airport noise calculation guidelines such as ECAC Doc.29 and ICAO Doc9911. In these guidelines, the directivity of flyover noise and the directivity at the start of takeoff roll on ground are prepared separately. A 90-degree dipole model is used for the directivity of the flyover noise, and another similar directivity is used for the directivity behind the start of takeoff roll. It is necessary to properly evaluate the directivity behind the takeoff roll because it has a large contribution to noise calculation of the vicinity of the airport. Therefore, we measured aircraft noise behind the start of takeoff roll with sound level meters placed half-concentrically around Narita Airport in Japan. From these measurement results, various types of aircraft noise directivity behind the takeoff roll are examined and considered the effects of weather conditions such as wind direction. Finally the differences from existing models are compared.

Gli stili APA, Harvard, Vancouver, ISO e altri

39

Водопьян, Е. А., Т. Н. Середа e В. И. Рябков. "АНАЛІЗ МЕТОДІВ ЗНИЖЕННЯ АВІАЦІЙНОГО ШУМУ В ДЖЕРЕЛІ І НА МІСЦЕВОСТІ". Open Information and Computer Integrated Technologies, n. 84 (2 luglio 2019): 144–56. http://dx.doi.org/10.32620/oikit.2019.84.07.

Testo completo

Abstract (sommario):

Currently, the topic of research of the aircraft noise influence on the environment is relevant. Aircraft and engine developers are constantly exploring ways to reduce noise following the new standards of the ICAO Committee (CAEP), whose main task is to protect the environment from the effects of aviation, to provide a comfortable environment for people exposed to aircraft noise and harmful substances. By limiting the permissible noise level of aircraft, CAEP initiates aircraft manufacturers to introduce the latest noise reduction technologies in their design. Measurement of aircraft noise is obviously an important type of research not only in the aircraft industry. The existing airports in the course of reconstruction, and new ones at the project development stage, should be mandatory tested on indicators of aircraft noise, which will penetrate into the surrounding area, including settlements of various sizes. Currently, scientists from different countries are making significant efforts to reduce the turbine noise of existing and prospective civil aircraft. Of course, nowadays, external jamming methods are commonly used. At the same time, an important way to reduce engine noise was the widespread use of so-called sound-absorbing structures. This article describes the direction of reducing the level of aircraft noise at the source and on the ground, near airports. To reduce the noise in the source of noise, the ways to reduce the turbulence of the streamlined aerodynamic bearing surfaces are considered by reducing their inductive resistance and matching the flow of gas in power plants. It is shown that the implementation of such approaches in modifications of domestic passenger and transport aircraft gives a positive result. When solving the problem of reducing noise on the ground, the study analyzed the effect of aviation noise on the population living near the airport as an example. The necessity of using soundproofing means in residential areas to reduce noise exposure is shown. An analysis of the effects of noise exposure is given. In conclusion, the preliminary results obtained in the course of research are presented.

Gli stili APA, Harvard, Vancouver, ISO e altri

40

Pang, Liping, Pei Li, Xiaodong Cao e Xiaoru Wanyan. "Experimental study of the changes in thermal expectation during simulated flights in a civil aircraft cabin mockup". Indoor and Built Environment 29, n. 9 (18 maggio 2020): 1277–88. http://dx.doi.org/10.1177/1420326x20925113.

Testo completo

Abstract (sommario):

Aircraft cabin thermal environment is a key issue on flight selection by passengers, especially for long-haul flights. Currently, there have been some studies on the passengers’ thermal comfort in civil aircraft cabins. However, information is still limited on the changes in passenger thermal expectation with flight time. In this study, an aircraft cabin mockup was built, and three experiments involving human subjects were carried out in order to study the in-flight thermal environment in winter, summer and autumn, respectively. The cabin temperatures during the experiments were controlled according to the thermal neutral temperature model derived from our previous study on actual flights. The thermal neutral temperature model was checked by experimental results. The changes in thermal expectation were investigated based on physical measurement and questionnaire survey. In each experiment, the changes in the mean thermal sensation votes of passengers were less than 1, while the cabin temperature increased by 2.8°C, 1.8°C and 2°C from the beginning to the end during the three experiments, respectively. With the increase in the simulated flight time, passengers gradually expected a slightly higher cabin temperature. This trend would become very obvious when the simulated flight time was longer than 2 h.

Gli stili APA, Harvard, Vancouver, ISO e altri

41

Gee, Kent L., Victor W. Sparrow, Michael M. James, J. Micah Downing, Christopher M. Hobbs, Thomas B. Gabrielson e Anthony A. Atchley. "Measurement and Prediction of Noise Propagation from a High-Power Jet Aircraft". AIAA Journal 45, n. 12 (dicembre 2007): 3003–6. http://dx.doi.org/10.2514/1.28985.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

42

Bhattarai, Mohan K., e B. K. Sapkota. "Study on Aircraft Noise Around Tribhuvan International Airport, Kathmandu, Nepal". Nepal Journal of Science and Technology 15, n. 1 (4 febbraio 2015): 139–44. http://dx.doi.org/10.3126/njst.v15i1.12031.

Testo completo

Abstract (sommario):

Present work was carried out to collect primary data from the field with the help of noise meter and thus spatial anddiurnal variation of background and aircraft noise level was analyzed. Seventeen sampling sites were chosennearby Tribhuwan International Airport (TIA) and air route of aircraft flyover. Noise measurements were carried outunder normal atmospheric environmental condition at temperature ranges from 25°C-30°C excluding rainy andwindy days. Among the sampling sites, the Equivalent Continuous Noise Level (LAeq) of background noise measuredmaximum at Balkumari (73.2 dBA) and minimum at Datidol (49.2 dBA). Noise meter was allowed to record aircraftnoise level when aircraft produced noise greater than background noise level and recorded until it reduced tobackground noise level. The maximum value of aircraft noise level, (LAeq) measured at Gothatar (101.5 dBA) whichlies north east from the TIA and at the same height as the airport ground and minimum at Datidol (63.5 dBA).Toanalyse the spatial variation of aircraft noise of different sampling sites, contour map was plotted with the help oforigin software. The LAeq of more than 60 percent sampling sites fall under the severe noise exposure class (> 75dBA) which causes substantial hearing loss. Implementation of noise control measurement and public awarenessare recommended to control adverse effect of noise pollution.DOI: http://dx.doi.org/10.3126/njst.v15i1.12031Nepal Journal of Science and TechnologyVol. 15, No.1 (2014) 139-144

Gli stili APA, Harvard, Vancouver, ISO e altri

43

Ganić, Emir, Jurica Ivošević e Bojana Mirković. "Impact of Aircraft Noise on Communities Near Belgrade Airport". Promet - Traffic&Transportation 33, n. 3 (31 maggio 2021): 323–35. http://dx.doi.org/10.7307/ptt.v33i3.3692.

Testo completo

Abstract (sommario):

The aim of this research was to examine the impact of aircraft noise on communities near the Belgrade Airport by conducting short-term noise measurements. Apart from the noise abatement procedure published in the Aeronautical Information Publication for Belgrade Airport, there are still neither publicly available reports of the actual efforts made towards the aircraft noise reduction nor the description of the current noise situation. In order to estimate the current noise situation, eighteen aircraft overflight noise measurements were taken in two settlements in specific sound-sensitive community areas around the Belgrade Airport. The results showed that level differences between background noise and aircraft overflights were higher than 10 dB for each measurement and could be considered significant. Furthermore, preliminary compatibility analysis with acoustic zoning was performed. Average daily noise levels were estimated from these short-term measurements and were compared to legal noise limits for different acoustic zones. The results indicate that in some cases noise levels exceed the legal threshold, which should encourage land use planners to include the issue of Belgrade acoustic zoning on the agenda, but also prompt Belgrade Airport to implement continuous noise and flight tracks monitoring.

Gli stili APA, Harvard, Vancouver, ISO e altri

44

Meng, Qing Hai. "Impulsive Noise Detection and Elimination Method for GPS Measurement Data". Applied Mechanics and Materials 556-562 (maggio 2014): 2783–86. http://dx.doi.org/10.4028/www.scientific.net/amm.556-562.2783.

Testo completo

Abstract (sommario):

For GPS measurement signal in aircraft experiment is often affected by transmission environment, and interfered with impulsive noise, hereby a SVD combined with wavelet neural network to detect and eliminate the impulsive noise method was proposed. The received GPS data is decomposed by SVD, and the decomposed component is acted as the input of wavelet neural network. Letts criterion is adopted to detect the impulsive noise according to the output residue error of the wavelet neural network. For the detection of the interference points of impulse noise, it can use wavelet network output to replace the measured value, so as to eliminate impulsive noise.

Gli stili APA, Harvard, Vancouver, ISO e altri

45

Jäger, David, Christoph Zellmann, Felix Schlatter e Jean Marc Wunderli. "Validation of the sonAIR aircraft noise simulation model". Noise Mapping 8, n. 1 (1 gennaio 2021): 95–107. http://dx.doi.org/10.1515/noise-2021-0007.

Testo completo

Abstract (sommario):

Abstract sonAIR is a recently developed aircraft noise simulation model designed for single flight simulation while still being applicable for calculation of entire airport scenarios. This paper presents a rigorous validation exercise, wherein roughly 20’000 single flights were simulated using the 22 currently available sonAIR emission models of turbofan aircraft and compared against noise measurements. The measurements were recorded with the noise monitoring terminals at Zurich and Geneva airport, Switzerland, and with additional microphones installed by the author’s institution. Data from 22 measurement positions were analyzed, covering all departure and approach routes at distances from 1.8 to 53 kilometers from the airports. sonAIR was found to be accurate for departures and approaches under different operating conditions and aircraft configuration. The mean overall differences between simulation and measurements were well below ±1 dB in terms of noise event levels, with standard deviations of ±1.7 dB respectively ±2.4 dB, depending on the model type. A few aircraft types that displayed larger deviations are discussed individually. A sensitivity analysis on the input data found the quality and level of detail of the land cover data to be critical for the simulation accuracy. Changes in other input data such as atmospheric profiles and buildings had non-significant impacts.

Gli stili APA, Harvard, Vancouver, ISO e altri

46

Choirunisa, Ristyna. "Hearing Loss And Health Complaints In Technicians Air Skadron 3 Iswahjudi Airport And Its Association With Aircraft Noise". JURNAL KESEHATAN LINGKUNGAN 11, n. 1 (1 febbraio 2019): 61. http://dx.doi.org/10.20473/jkl.v11i1.2019.61-68.

Testo completo

Abstract (sommario):

Aviation is the most significant part of Indonesian Air Force duty. Air Force’s aircraft takes a role not only as Indonesian army agency transportation vehicle but also crucial for Indonesian air territory security protection. However the level of noises resulted from Air Force aviation operation activity such as take off of aircraft reached 130 dBA, so the operation can causes auditory and non auditory adverse effects such as communication, physiological disorder, and psycological disorder. The aim of this study is to analyze factors induced to the hearing loss and analyze the effects of aircraft noises to technician health complaints. This research using case control approach and it was conducted by recruiting subject respondents group randomly of 20 officers includes of 10 technician as study group and 10 non technician as control group. The measurement of aircraft noise level was performed 4 times during 8 hours used Sound Level Meter. The results of aircraft noise measurement in flightline area was exceeding the threshold value of 95,56 dBA. The results of the study shows that aircraft noise significantly associated with to technician hearing loss p-value=0,026 (Spearman correlation test, p<0,05). Other factors that are associated significantly with technician hearing loss include aged p-value=0,023 (Pearson correlation test, p<0,05). Insignificant association is showed for work period with p-value=0,038 (spearman correlation test, p<0,05). In addition, the aircraft noise is associated to health complaint as psychological disorder p-value=0,033 (simple logistic regression test, p-value <0,05). The conclusion of research is that aircraft activities affected hearing loss and technician psychological disorder.

Gli stili APA, Harvard, Vancouver, ISO e altri

47

Sun, J., S. P. Burns, D. Vandemark, M. A. Donelan, L. Mahrt, Timothy L. Crawford, T. H. C. Herbers, G. H. Crescenti e J. R. French. "Measurement of Directional Wave Spectra Using Aircraft Laser Altimeters". Journal of Atmospheric and Oceanic Technology 22, n. 7 (1 luglio 2005): 869–85. http://dx.doi.org/10.1175/jtech1729.1.

Testo completo

Abstract (sommario):

Abstract A remote sensing method to measure directional oceanic surface waves by three laser altimeters on the NOAA LongEZ aircraft is investigated. To examine feasibility and sensitivity of the wavelet analysis method to various waves, aircraft motions, and aircraft flight directions relative to wave propagation directions, idealized surface waves are simulated from various idealized aircraft flights. In addition, the wavelet analysis method is also applied to two cases from field measurements, and the results are compared with traditional wave spectra from buoys. Since the wavelet analysis method relies on the “wave slopes” measured through phase differences between the time series of the laser distances between the aircraft and sea surface at spatially separated locations, the resolved directional wavenumber and wave propagation direction are not affected by aircraft motions if the resolved frequencies of the aircraft motion and the wave are not the same. However, the encounter wave frequency, which is directly resolved using the laser measurement from the moving aircraft, is affected by the Doppler shift due to aircraft motion relative to wave propagations. The wavelet analysis method could fail if the aircraft flies in the direction such that the aircraft speed along the wave propagation direction is the same as the wave phase speed (i.e., the aircraft flies along wave crests or troughs) or if two waves with different wavelengths and phase speed have the same encountered wavelength from the aircraft. In addition, the data noise due to laser measurement uncertainty or natural isotropic surface elevation perturbations can also affect the relative phase difference between the laser distance measurements, which in turn affects the accuracy of the resolved wavenumber and wave propagation direction. The smallest waves measured by the lasers depend on laser sampling rate and horizontal distances between the lasers (for the LongEZ this is 2 m). The resolved wave direction and wavenumber at the peak wave from the two field experiments compared well with on-site buoy observations. Overall, the study demonstrates that three spatially separated laser altimeters on moving platforms can be utilized to resolve two-dimensional wave spectra.

Gli stili APA, Harvard, Vancouver, ISO e altri

48

Stansfeld, S. A., C. R. Clark, L. M. Jenkins e A. Tarnopolsky. "Sensitivity to noise in a community sample: I. Measurement of psychiatric disorder and personality". Psychological Medicine 15, n. 2 (maggio 1985): 243–54. http://dx.doi.org/10.1017/s0033291700023527.

Testo completo

Abstract (sommario):

SynopsisA sample of 77 women of high and low noise sensitivity, living in areas of high and low exposure to aircraft noise drawn from the 1977 West London Survey, were interviewed in the community in 1980. Women of high, intermediate and low noise sensitivity in 1980 were compared for measures of psychiatric disorder, personality and reactivity to the other sensory stimuli. In addition, the noise sensitivity measures defining the three groups in 1980 were compared with further measures of noise sensitivity. High noise sensitive women exhibited significantly more psychiatric symptoms, higher neuroticism scores, and greater reactivity to other sensory stimuli than intermediate and low noise sensitive women.

Gli stili APA, Harvard, Vancouver, ISO e altri

49

Kloet, N., S. Watkins e R. Clothier. "Acoustic signature measurement of small multi-rotor unmanned aircraft systems". International Journal of Micro Air Vehicles 9, n. 1 (9 febbraio 2017): 3–14. http://dx.doi.org/10.1177/1756829316681868.

Testo completo

Abstract (sommario):

This work describes the testing involved in generating an acoustic signature profile of a small multi-rotor unmanned aircraft system. A typical multi-rotor unmanned aircraft system, with a weight of approximately 2.1 kg, was used for sound pressure level measurements. This study established a relationship between distance, altitude and sound pressure level, finding that the sound decays approximately in line with 6 dB(A) reduction for a doubling of distance. The effect of the orientation of the multi-rotor unmanned aircraft system was also investigated. It was determined that the sound profile does not vary significantly around the periphery of the multi-rotor unmanned aircraft system in the propeller-plane. However, when measured with the observer underneath the multi-rotor unmanned aircraft system, the sound pressure level was found to vary by as much as 10 dB(A), with the greatest sound pressure level at approximately 45° from horizontal. Finally, an acoustic array was used to measure key frequencies for the main sound sources: motors and propellers. It was found that extraneous noise from the multi-rotor unmanned aircraft system frame vibration and mounting methods was also common. Despite relatively low levels of sound being measured (especially when compared with conventional aircraft and rotorcraft), the increasing numbers of unmanned aircraft systems in urban environments, close to humans and dwellings, suggests that increasing complaints are likely. Thus, further research was suggested, including expanding the range of multi-rotor unmanned aircraft system to be tested, introducing DGPS, improving the mounting for indoor testing, and psychoacoustic analysis of the sound.

Gli stili APA, Harvard, Vancouver, ISO e altri

50

Riadiany, Pradita Wira, e Sugeng Abdullah. "STUDI TENTANG INTENSITAS SUARA DANUPAYA PENGENDALIAN KEBISINGAN DI BANDAR UDARAHUSEIN SASTRANEGARA BANDUNG TAHUN 2014". Buletin Keslingmas 34, n. 1 (31 marzo 2015): 36–53. http://dx.doi.org/10.31983/keslingmas.v34i1.3022.

Testo completo

Abstract (sommario):

PDAM Tirtawening Environmental Quality Control Measurement Laboratory Bandung stated thatHusein Sastranegara airport had highest noise intensity equal to 89.83 dB (A) so that the researcherwants to investigate the sound intensity and noise control in the Husein Sastranegara airport Bandung2014.The research design used was descriptive research which was intended to obtain vivid descriptionrelated sound intensity and noise control in Husein Sastranegara airport Bandung 2014 with five-pointmeasurement that describes the apron (aircraft parking space), check in / luggage space and the ticketprocess, passengers waiting room, public park, and housing.The research results shows that the sound intensity in Husein Sastranegara airport Bandungmeasurement in all locations for 83.78 dB (A) on the apron (aircraft parking area), 72.66 dB (A) at thecheck in / hall ticket and luggage process, 75.37 dB (A) in the passenger waiting room, 65.93 dB (A) atthe public parking lot and 68.52 dB (A) at the housing. The highest sound intensity results was in theapron (aircraft parking area) 85.33 dB (A) at 08:40 am.Manager of Husein Sastranegara airport Bandung expected to encourage the airports employeesto use personal protective equipment such as ear muff while on duty at the apron (aircraft parking) andconduct sound intensity measurement on a regular basis in order to recognize hazard that can interferewith employee activities.

Gli stili APA, Harvard, Vancouver, ISO e altri

Articoli di riviste sul tema "Aircraft cabins Noise Measurement"

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili