Noise Survey Research Articles

Seismology in the Cloud: A New Streaming Workflow

AbstractData-intensive research in seismology is experiencing a recent boom, driven in part by large volumes of available data and advances in the growing field of data science. However, there are significant barriers to processing large data volumes, such as long retrieval times from data repositories, complex data management, and limited computational resources. New tools and platforms have reduced the barriers to entry for scientific cluster computing, including the maturation of the commercial cloud as an accessible instrument for research. In this work, we build a customized research cluster in the cloud to test a new workflow for large-scale seismic analysis, in which data are processed as a stream (retrieved on-the-fly and acted upon without storing), with data from the Incorporated Research Institutions for Seismology Data Management Center. We use this workflow to deploy a spectral peak detection algorithm over 5.6 TB of compressed continuous seismic data from 2074 stations of the USArray Transportable Array EarthScope network. Using a 50-node cluster in the cloud, we completed the noise survey in 80 hr, with an average data throughput of 1.7 GB per minute. By varying cluster sizes, we find the scaling of our analysis to be sublinear, due to a combination of algorithmic limitations and data center response times. The cloud-based streaming workflow represents an order-of-magnitude increase in acquisition and processing speed compared to a traditional download-store-process workflow, and offers the additional benefits of employing a flexible, accessible, and widely used computing architecture. It is limited, however, due to its reliance on Internet transfer speeds and data center service capacity, and may not work well for repeated analyses or those for which even higher data throughputs are needed. These research applications will require a new class of cloud-native approaches in which both data and analysis are in the cloud.

Roaring and repetition: How bowhead whales adjust their call density and source level (Lombard effect) in the presence of natural and seismic airgun survey noise.

Over 500 000 automated and manual acoustic localizations, measured over seven years between 2008 and 2014, were used to examine how natural wind-driven noise and anthropogenic seismic airgun survey noise influence bowhead whale call densities (calls/km2/min) and source levels during their fall migration in the Alaskan Beaufort Sea. Noise masking effects, which confound measurements of behavioral changes, were removed using a modified point transect theory. The authors found that mean call densities generally rose with increasing continuous wind-driven noise levels. The occurrence of weak airgun pulse sounds also prompted an increase in call density equivalent to a 10-15 dB change in natural noise level, but call density then dropped substantially with increasing cumulative sound exposure level (cSEL) from received airgun pulses. At low in-band noise levels the mean source level of the acoustically-active population changed to nearly perfectly compensate for noise increases, but as noise levels increased further the mean source level failed to keep pace, reducing the population's communication space. An increase of >40 dB cSEL from seismic airgun activity led to an increase in source levels of just a few decibels. These results have implications for bowhead acoustic density estimation, and evaluations of the masking impacts of anthropogenic noise.

Laboratory test of a superconducting gravimeter without a cryogenic refrigerator: implications for noise surveys in geothermal fields

ABSTRACT Development of an accurate reservoir model and prediction of reservoir behaviour associated with geothermal exploitation using that model are fundamentally important for sustainable geothermal utilisation. Gravity observation for a few tens of days after a field-wide shut-in of geothermal wells potentially provides valuable constraints to improve reservoir models. We investigated the applicability of superconducting gravimeters (SGs) to short-term observations after shut-ins, as a first step towards the development of a method for reservoir model improvement using short-term gravity data. Results from a reservoir simulation of a shut-in at a geothermal field in Japan showed that gravity change at 20 days after the shut-in was 10 nm/s2. To detect such changes with SGs, locations of SG stations should be chosen to minimise noise sufficient to resolve the signal. Considering that field operations and traffic in geothermal fields can make SG data noisy, laboratory gravity measurements were carried out with a SG to investigate the influence of noise level on signal detection. Test masses, which produced a gravity change (7.7–9.0 nm/s2) comparable to the simulation result, were repeatedly placed and removed above the SG during both day and night times with different ambient noise levels. Test results showed that noise level greatly affected signal detection. The signal was only detected twice, under low-noise conditions with the standard deviations of 1.1 and 5.3 nm/s2. In addition, tests in which the SG was operated without a cryogenic refrigerator revealed that the absence of the refrigerator did not increase the noise level. Enhancing the portability of a SG by reducing its weight can make multi-location noise surveys feasible. Our method, of combining reservoir simulations and preliminary noise surveys, would enable successful SG observations to be made in relatively short periods after shut-ins, which would possibly contribute to the development of a method to obtain additional constraints to be used for reservoir model calibration.

Street‐Scale Mapping of Urban Radio Frequency Noise at Very High Frequency and Ultra High Frequency

AbstractModern measurement campaigns of man‐made radio frequency (RF) noise have reported results from fixed locations that are assumed to be representative of the surroundings. Models derived from these measurements include parameters to express the variability in time and in space over very large distances (i.e., differences between cities). Despite the rapidly evolving mixture of noise sources, especially in modern urban environments, spatial variation of RF noise power at the scale of streets and blocks is essentially unknown in the very high frequency and ultra high frequency bands. Using a portable calibrated noise measurement system of our design, RF noise was recorded over a 1‐MHz bandwidth for frequencies of 142.0, 246.5, and 972 MHz. Noise surveys were conducted during daytime working hours in two different neighborhoods within Boston, Massachusetts, USA, with each survey transiting a fixed, several kilometer long route, repeated twice to enable separation of temporal from spatial variability. Significant and spatially repeatable variations in median power, peak power, and voltage deviation were observed over distances of tens to hundreds of meters, dependent upon the measurement frequency. The observed spatial patterns of median and peak power appear to be repeatable on timescales of hours to weeks, and likely beyond, suggesting that these noise patterns are persistent features of the urban environment.

Community noise exposure and annoyance: A multilevel description

An overview is provided of multilevel modeling of community noise annoyance. By multilevel, it is meant that noise exposure and noise tolerance vary on the community level, and among individuals within the communities. Although these assumptions are rather simple, they lead to a rigorous statistical model with characteristics consistent with noise survey data. Regression analyses with a multilevel, generalized linear model (GLM) enable the model parameters and their variations at the community and individual levels to be distinguished and quantified. Based on a meta-analysis of transportation noise, the community-level and individual-level noise tolerance variances are both evident, although the individual-level variance is stronger. The significance of community-level variance is consistent with the recently introduced concept of community tolerance level (CTL). Although the multilevel model describes and quantifies the community-level variations, it does not by itself explain why communities differ, or how to account for these differences in regulations. Future research should address the relationships between community tolerance variations and factors such as soundscape disturbance and attitude toward the most prominent noise sources.

Exposure and inequity: assessing commuter vulnerability and the quality of noise environment on urban arterials

ABSTRACTIt is a well-established fact that a mobility corridor is a source of various street level noises impacting unprotected commuters. Although this fact is understood rarely has it been investigated to evince the category of commuters it affects or its intensity? The purpose of this study is to characterize and establish the noise environment, elicit the degree of noise exposure and establish the inequity that gets distributed in a common public space on vulnerable commuter categories. For this study noise levels were recorded at intersections and mid segments of corridors at 24 locations to assess the noise environments. The degree of exposure and equity were derived using a Semantic differential (SD) rating scale. The study consisted of two parts: noise survey and the traffic stream and modal attribute study. The results were analysed statistically and a rating scale developed to inform analysis and interpretation. The paper dwells on two related aspects of vulnerability; exposure and equity. The study reveals that at all locations surveyed noise levels remained far above prescribed limits. This study indicates the dominance of MT’s in terms of volume and road usage and showed that although slow commuters and NMT’s generated lesser noise on road environments inequity is foisted on them when compared to MT modes. Results indicate that the percentage of the total volume of non-motorized (NMT) commuters in the two road environments studied does not affect the noise climate. All noise descriptors indicate high noise emissions the sources of which are motorized transport as compared to the NMT’s which are susceptible and are comparatively more sensitive to this externality. The vulnerability score is derived on a rating scale. The vulnerability matrix and scores developed show high scores for slower modes indicative of the intensity of exposure based on factors evolved from the study.

ENVIRONMENTAL AND OCCUPATIONAL NOISE MANAGEMENT PROCESS IN CEMENT INDUSTRY

The main environmental issues associated with cement production are the consumption of raw materials, energy use and emissions in the air. Noise emissions occur throughout the whole cement manufacturing process - from preparing and processing raw materials, from the clinker burning and cement production process, from material storage as well as from the dispatch and shipping of the final products. The heavy machinery and large fans used in the cement manufacturing process can give rise to noise emissions. Cement Plants are required to comply with standards for reduction in line with national legislation, and to conduct measurements and perform noise surveys. Having this in mind, A TITAN Group Usje Cement Plant in Skopje, following their strong commitment to high environmental performance and Corporate Social Responsibility and Sustainable Development Policy in 2013-2014 have engaged an AMBICON Lab (Faculty of Natural and Technical Sciences) from Stip, to conduct a Noise Control Study in order to identify noise sources within cement plant and marl quarry, determine their impacts on nearby residents and develop noise control/protection strategies. During the past three years, the Usje Cement plant has implemented most of the noise control measures proposed in this Study. Also, a follow-up study during 2016-2017 was conducted in order to assess the effectiveness of measures taken. This paper presents the outcomes of noise reduction measures taken. Keywords: noise, cement industry, process management, measures, environment

ACOUSTIC ANALYSIS AND MEASUREMENTS OF MEGA YACHTS DURING CONSTRUCTION

Noise is a critical parameter for super/mega yachts which can be verified only in the final stage of a mega yacht building project. Although there are more and more advanced methods to predict noise prior to the sea trials, verification has to be delayed until the noise survey is conducted during the sea trial. A new methodology is proposed based on measurements during construction to determine the transmission losses of both airborne and structure borne noise and propagation of the sound from the source to the receiver using these measurements. A 66 meter mega yacht case study is presented with measurements of airborne noise emitted through an omni-directional dodecahedron loudspeaker and measurements of structure borne noise generated by a tapping device. Both sound pressure levels and vibrations are measured to derive the transmission losses. A source-path-receiver method-based prediction tool, SNoPP, is employed to project the measurements into the final noise predictions. Comparisons between the measurements and the predictions are also presented.

Seismic site classification and correlation between VS and SPT-N for deep soil sites in Indo-Gangetic Basin

The Indo-Gangetic Basin (IGB) is occupied by the thick deposits of different types of loose to dense soil due to the active sedimentation. Till date, no detailed study has been carried out on seismic site characterization, and classification considering shear wave velocity >50 m depth. In this study, surface wave survey was used for determining the shear wave velocity (VS) variation with depth at 276 locations in the IGB using low-frequency geophones by performing combined active (Multichannel analysis of surface waves, MASW) and passive (Ambient Noise) surveys. To study the spatial variability of VS, based on the sediment deposition and geological variability, the whole IGB has been divided into Punjab-Haryana region (PHR), Uttar Pradesh region (UPR), and Bihar region (BR). Firstly, using the least square, orthogonal, and mixed effect approaches, a new correlation between the VS and SPT-N has been developed for all the three regions separately. The VS and SPT-N correlation has been developed considering both corrected and uncorrected SPT-N value. The residuals have been determined using the observed and the predicted VS values from newly developed VS and SPT-N correlation from each approach. For the same SPT-N value, correlation for UPR region is predicting high VS value as compared to other two regions. Studying the variation of residuals with VS, it is determined that the mixed effect is performing better for VS ≤ 250 m/s and orthogonal for VS > 250 m/s. At higher N-value, difference between VS values for all the three regions are noticeable. Further, the newly developed relationships are compared with the existing VS and SPT-N relationship. Additionally, the IGB is classified based on the average shear wave velocity in the top 30 m (VS30) as per the National Earthquake Hazards Reduction Program (NEHRP) and compared with Eurocode 8 (EC8). The VS30 is high in the southern part of the BR and UPR and low near to the active channel deposition and major part of the IGB is classified as seismic site class D. Most of the IGB sites have experienced severe damage either due to local site effects or liquefaction during past earthquakes. Therefore, the spatial variability of the average shear wave velocity at different depths, i.e., at top 5,10,15,20, 30 50, 100, 150, 200, 250 and 300 m are also estimated and compared with the available basement depth map.

A survey method of sound environment: Effects of noise and social survey method

A survey method of sound environment: Effects of noise and social survey method

Structural equation models of road traffic and aircraft noise annoyance in Vietnam

Socio-acoustic surveys on the community response to transportation noise were carried out in five Vietnamese cities from 2005 to 2013. Approximately 9900 responses were obtained from these surveys. Variations in exposureâ–“response curves were found among different regions and noise sources. Various degrees of annoyance resulting from the same noise exposure implied the effects of non-acoustic factors, such as urban lifestyles and attitudes towards noise sources. To assess these effects, structural equation models were developed in this study by linking questionnaire items from the socio-acoustic surveys on road traffic and aircraft noise annoyance. The sample sizes were 3783 and 1973 for road traffic and aircraft noise surveys, respectively; therefore, they were sufficiently large to estimate and compare the models among cities and between two types of noise source. The final model included three latent factors: sensitivity, activity interference, and satisfaction with the living environment. Sensitivity to noise, vibration, and heat were determinants of personal sensitivity. Activity interference was measured by awakening during sleep, rest, and listening disturbances. The quietness of living areas, preference for living areas, and comfort during the dry season were used to determine satisfaction with the living environment. A good model fit was observed, indicating that sensitivity and satisfaction with the living environment were the main modifiers of noise annoyance in Vietnam. The findings of this study suggest measures for reducing noise annoyance among urban residents in Vietnam.

Standardizing industrial hygiene data collection forms used by workers’ compensation insurers

Workers’ compensation (WC) insurers collect large amounts of industrial hygiene (IH) data in the United States. The data collected is not easily accessible for research or surveillance purposes. Individual WC insurers are using computerized systems to standardize and store the IH data, leaving a gap in standardization among the different WC insurers. This study sought to standardize IH data collection among WC insurers and to determine the feasibility of pooling collected IH data. IH air and noise survey forms were collected from WC insurers. Data fields on the forms were evaluated for importance and a study list of core fields was developed. The core study list was presented to an IH review panel for review before finalization. The final core study list was compared to recommendations published by the American Conference of Governmental Industrial Hygienists (ACGIH) and the American Industrial Hygiene Association (AIHA). Fifty-nine forms from 10 organizations were collected. Industrial hygienists from research organizations, state-based WC insurers, and private WC insurers participated in the data field evaluation and on the review panel. For both air and noise survey forms, more than half the data fields (55% and 54%, respectively) were ranked as “essential.” Three of the four fields in the worker and control observations category ranked “essential” were found less than half of the time on both types of survey forms. The study list of core data elements consisted of more than half of the data fields from both the air and noise survey forms. Three additional fields were added based on the comparison to the ACGIH-AIHA recommendations. Data fields essential to standardizing IH data collection were identified and verified. The “essential” data fields will be made available and have the potential to be incorporated into WC insurers electronic IH data management systems. Future research should focus on other IH survey forms, such as those used in ergonomic assessments and specific chemical exposures, and methods to transfer data fields to electronic platforms.

Workplace noise assessments by open-plan office occupants: Relationship with ISO 3382-3 metrics, and psychoacoustic parameters

ISO 3382-3:2012 is the international standard for measuring the acoustics of open-plan offices. These measurements are performed in unoccupied offices, and it has recently been shown that some of the ISO 3382-3 metrics, especially distraction distance, are useful in predicting the occupants’ perceived disturbance due to noise. The current research compares the ISO 3382-3 metrics, with several psychoacoustic parameters (loudness, fluctuation strength, etc.) derived from measurements done in an occupied state of open-plan offices, in terms of their usefulness in predicting occupants’ perception of several aspects of workplace noise. This comparison was based on using measurements performed in several offices in both occupied and unoccupied states, along with a workplace noise survey that was conducted in these offices. The results will enable a more comprehensive understanding of noise-related issues in open-plan offices, as it involves both physical acoustic, and psychoacoustic considerations.

Transdimensional Bayesian inversion of time-domain airborne EM data

To reduce the dependence of EM inversion on the choice of initial model and to obtain the global minimum, we apply transdimensional Bayesian inversion to time-domain airborne electromagnetic data. The transdimensional Bayesian inversion uses the Monte Carlo method to search the model space and yields models that simultaneously satisfy the acceptance probability and data fitting requirements. Finally, we obtain the probability distribution and uncertainty of the model parameters as well as the maximum probability. Because it is difficult to know the height of the transmitting source during flight, we consider a fixed and a variable flight height. Furthermore, we introduce weights into the prior probability density function of the resistivity and adjust the constraint strength in the inversion model by changing the weighing coefficients. This effectively solves the problem of unsatisfactory inversion results in the middle high-resistivity layer. We validate the proposed method by inverting synthetic data with 3% Gaussian noise and field survey data.

A comparison of noise mapping data and people’s assessment of annoyance: How can noise action plans be improved?

In this paper the results of noise maps counted for cars and trams, in 10 areas in the city of Poznań, are analyzed in the context of possible action plans. These results are compared with the information from surveys, involving 794 participants, performed at the same 10 areas. The general results showed that basing solely on the values of noise indicators, i.e. information from the noise maps, is not sufficient for reliable planning of noise action plans, particularly those created in response to multiple noise sources. The exceedance of a noise limit for a given sound source does not necessarily mean that this source is the most annoying for inhabitants.To find a solution to this problem, we propose conducting dedicated noise surveys in the specific areas in each city (in which the noise maps are calculated) where we know a priori that more than one noise source will occur at the same time and could be potentially annoying. In the proposed survey we suggest using two specified questions: whether a given sound source is annoying or not, and which sound source should be the first one to be eliminated, if this is possible.This new survey proposal is the result of an analysis of the survey performed within this study. Some methodological changes are proposed with regard to the survey that was actually used. This new approach could improve decisions about action plans and provide more complex information about peoples’ assessment of noise annoyance evoked by different sound sources.

Fit testing of a hearing protection device with integrated in-ear noise exposure monitoring

In-the-ear hearing protectors are often used in high-noise environments, such as in military operations and during weapons training. The fit of such a hearing protection device in the ear canal can cause significant variability in the noise dose experienced, an important factor in characterizing the auditory health risk. Our approach for improved dose estimates under these conditions involves a portable noise recorder used to capture in-the-ear noise behind a hearing protector, and on-body noise, while assessing hearing protection fit throughout recording. In this presentation we describe evaluation of this system using ANSI S12.42 testing using a shock tube and an acoustic test fixture, to evaluate impulse peak reduction and for measurement validation. Also explored were angle dependent effects on the peak insertion loss and measurement accuracy of the on-body recorder. An exploratory study was conducted with a small sample of experimenters during a recent Navy-sponsored noise survey conducted at Marine Corps Base Quantico. Results will be presented from a shooter’s ear and a nominal instructor’s position as well as from bystanders observing at a firing range. Our results show good correspondence between behavioral fit-testing of insertion loss and estimated protection from the in-ear and on-body microphones. [Work supported by ONR.]

An Exploratory Survey of Sound Levels in New York City Restaurants and Bars

For several decades, there has been a significant need to better educate the public about noise pollution. A small number of small-scale studies have focused on the sound levels of restaurants and their impact on health and hearing. There have also been an increasing number of media articles stating that eating and drinking venues are getting increasingly loud making it more difficult for people to connect with others in conversation. This study reports on an exploratory large-scale noise survey of sound levels of 2376 restaurants and bars in New York City using a novel smart-phone application and categorized them based on how quiet or loud they were. The results suggest that: 1) A significant number of venues have high sound levels that are not conducive to conversation and may be endangering the health of patrons and employees, 2) that the reported sound levels by the venue managers on their online public business pages generally underestimated actual sound levels, and 3) the average sound levels in restaurants and bars are correlated by neighborhood and type of cuisine.

Hospital noise mitigation

A review of the literature today concerning noise in hospitals, both public and peer review, points to a continual increase in noise complaints from medical staff and patients in hospitals. One would expect that things would be getting better by now, but this is not the case. Noise surveys that we have recently conducted suggest that though unsatisfactory conditions are widespread, a list of simple, cost effective solutions has proven to be effective. This paper presents an array of actual projects detailing the development of remedies for noise annoyance in hospitals in an effort to increase the comfort and performance of medical staff and patients.

Multilevel modeling and regression as applied to community noise annoyance surveys

Tolerance to noise varies between communities, and between individuals comprising the communities. A multilevel modeling approach is useful for capturing such individual- and community-level variations. Here, we consider a model in which the community-level variations are sampled explicitly with community noise surveys, while the individual-level variations are sampled only in a statistical sense (i.e., hidden). The community-level variations are specifically quantified by the community tolerance level (CTL) [Fidell et al., J. Acoust. Soc. Am. 130(2), 791-806 (2011)]. Simulations based on the multilevel model indicate that the community- and individual-level variations have distinct statistical signatures, both of which are evident in noise annoyance surveys involving transportation noise. The annoyance curve for a previously unsurveyed community depends on the mean and variance of the CTL, and the sum of the hidden variances in noise tolerance and exposure among individuals in the community. Regression analyses of transportation noise annoyance using a multilevel, generalized linear model (GLM) enable noise tolerances and their variations at the two model levels to be distinguished and quantified.

CTL—A useful tool for inter-survey comparisons

The concept of Community Tolerance Level was presented in 2011 and in subsequent analyses the CTL has proven to be a useful tool for comparing results from different surveys on noise annoyance. The CTL provides a robust single-number description of the prevalence of annoyance in a community noise survey. It has been shown that accurate predictions of the prevalence of highly annoyed residents can be achieved by relatively few survey interviews as the selection of respondents does not have to cover the whole range of exposure. A re-analysis of existing studies on aircraft noise annoyance has shown that there has been virtually no change in people's response to this type of noise over the past 50 years, but there is a distinct difference in the response depending on the rate of which the noise situation has been changing. A similar analysis of results on road traffic noise from surveys conducted over a period of more than 50 years, will be presented.