Environmental Noise Levels Research Articles

RESEARCH AND MAPPING OF LOW FREQUENCY NOISE GENERATED BY POWER PLANTS OF INDUSTRIAL ENTREPRISES

Environmental noise level from industrial enterprises is constantly increasing, especially in low frequency range. This paper presents the results of research and mapping of low frequency noise generated by power plants of industrial enterprises. Environmental noise mapping results of urban territory of Samara region of Russia are also presented. Results of noise measurements during industrial enterprises operation (on the example of “KuibyshevAzot” company) are showing that in some measuring points there were exceeding values compared with Russian sanitary norms requirements. The most serious problem is low frequency noise impact.

Coronavirus disease 2019 (COVID-19) and psychological distress in China: Does neighbourhood matter?

Using individual data (n = 937) obtained from an online questionnaire between 20th January and 13th February, the early stage of the outbreak of the Coronavirus Disease 2019 (COVID-19) in 2020, we explore the direct association between people's perceptions of Coronavirus Disease 2019 (COVID-19) and psychological distress. We further examine the moderating role of neighbourhood environment and this distress. We find that people living in infected communities tend to perceive higher level of psychological distress compared to people living in uninfected communities. People's expected duration of COVID-19 is associated with higher psychological distress and this is partially moderated by the perception of neighbourhood noise level and overall environment quality. Additional results quantify the evidence that a quiet and well maintained neighbourhood environment could reduce the negative influences of expectation of a long duration of COVID-19 on people's psychological distress.

Noise annoyance during COVID-19 lockdown: A research of public opinion before and during the pandemic.

Strict lockdown strategies to stop the spread of COVID-19 have caused a decrease in environmental noise levels and introduced new noise conditions in dwellings. The present study has investigated the impact of the forced lockdown in Turkey on noise annoyances due to traffic, neighbors, and personal dwellings, as well as the concern of being heard by neighbors, and overall dwelling satisfaction in an online questionnaire. The stress and anxiety levels of respondents were also investigated. The survey obtained 1053 respondents. Additionally, environmental noise levels were measured over 24-h at two locations and compared with results before the pandemic. The results clearly exhibit that environmental noise levels and annoyance due to the noise levels dropped significantly. The annoyance drop was larger in previously noisier environments than previously tranquil locations. Noise annoyance due to neighbor noise did not change significantly; however, noise annoyance due to one's own dwelling increased. The results also confirmed an overall increase in dwelling satisfactions indicating a correlation between dwelling satisfaction and lower environmental noise levels. Although the results confirmed that noise annoyance was positively correlated with stress and anxiety levels, the change of annoyance between before and during lockdown was shown to be independent from the stress and anxiety level.

Construction and Experimental Verification of Novel Online Partial Discharge Monitoring System Using Power Line Communication

In this research, we aim to construct a completely new partial discharge (PD) monitoring system that applies inexpensive power line communication (PLC). We have proposed a PD detection method and monitoring system (PDMS-PLC) on the basis of PLC signal transfer rare is affected by an error due to disturbance. An attempt is made to identify PD source from the quadrant dependence of information transmission rate (hereinafter referred to PHY rate [Mbps]) by selecting a pair of quadrants of applied voltage phase; i.e. 1st and 3rd quadrants, or 2nd and 4th ones. It was found that the PHY (Abbreviation for the lowest physical layer in the OSI (open systems interconnection) hierarchical model.) rate number distribution reflects the PD characteristics obtained by the phase resolved PD (PRPD) pattern. Environmental noise level is also measured at an actual substation using PDMS-PLC. Consequently, the applicability of PDMS-PLC to PD signal detection and defect type identification is suggested.

Level and Noise Sources in the Neonatal Intensive Care Unit of a Reference Hospital.

Objective.Determine the level of environmental and periauricular noise in preterm babies and identify the sources generating noise in the Neonatal Intensive Care Unit -NICU- of a reference hospital in San Luis Potosí, Mexico.Methods.Cross-sectional and analytic study of the measurement of the level of environmental noise in five critical areas of the NICU, according with the method of measurement of noise from fixed sources by the Mexican Official Norm and periauricular at 20 cm from the preterm patient’s pinna. The measurements were carried out during three representative days of a week, morning, evening and nocturnal shifts. A STEREN 400 sound level meter was used with 30 to 130 dB range of measurement and a rate of 0.5 s.Results.The average level of periauricular noise (64.5±1.91dB) was higher than the environmental noise (63.3±1.74 dB) during the days and shifts evaluated. The principal noise sources were activities carried out by the staff, like the nursing change of shift and conversations by the staff, which raised the level continuously or intermittently, operation of vital support equipment (alarms) and incidences (clashing of baby bottles and moving furnishings) produced sudden rises of noise.Conclusions.Environmental and periauricular noise in NICU exceeds by two and almost three times the 45 dB during the day and 35 dB at night from the norm in hospitals. It is necessary to implement permanent noise reduction programs to prevent sequelae in the preterm infant and professional burnout in the nursing staff.

A review of the application of active noise control technologies on windows: Challenges and limitations

Traffic, construction and industry noises are the main sources for noise pollution for mega cities. These noises mainly propagate through the windows of the dwelling and can degrade the comfort level of a living space. Various studies have demonstrated that the active noise control (ANC) system is a potential technique which can be applied on the windows in order to mitigate environmental noise level inside a building. The present paper attempted to give a detailed description for the use of ANC system in windows under various scenarios, namely closed, fully opened and partially opened windows. For closed windows, the most common design methods of ANC system are cavity and panel controls. For opened window, the secondary source is either mounted on the frame of the window or implanted in the walls. For partially opened windows, the most common design method is cavity control. Advantages and shortcomings of various ANC designs were presented and discussed in the present study.

Optimal environment localization

Quantum channels model many physical processes. For this reason, hypothesis testing between quantum channels is a fundamental task in quantum information theory. Here we consider the paradigmatic case of channel position finding, where the aim is to determine the position of a target quantum channel within a sequence of background channels. We explore this model in the setting of bosonic systems, considering Gaussian channels with the same transmissivity (or gain) but different levels of environmental noise. Thus the goal of the problem becomes detecting the position of a target environment among a number of identical background environments, all acting on an input multi-mode system. We derive bounds for the ultimate error probability affecting this multi-ary discrimination problem and find an analytic condition for quantum advantage over protocols involving classical input states. We also design an explicit protocol that gives numerical bounds on the ultimate error probability and often achieves quantum advantage. Finally, we consider direct applications of the model for tasks of thermal imaging (finding a warmer pixel in a colder background) and quantum communication (for localizing a different level of noise in a sequence of lines or a frequency spectrum).

Nighttime environmental noise and semen quality: A single fertility center cohort study

With increased population and urban development, there are growing concerns regarding health impacts of environmental noise. We assessed the relationship between nighttime environmental noise and semen quality of men who visited for fertility evaluation. This is a retrospective cohort study of 1,972 male patient who had undertaken semen analysis between 2016–2018 at a single fertility center of Seoul, South Korea. We used environmental noise data of National Noise Information System (NNIS), Korea. Using semiannual nighttime noise measurement closest to the time of semen sampling, individual noise exposures at each patient’s geocoded address were estimated with empirical Bayesian kriging method. We explored the association between environmental noise and semen quality indicators (volume, concentration, % of progressive motility, vitality, normal morphology, total motile sperm count, oligozoospermia, asthenozoospermia, and severe teratozoospermia) using multivariable regression and generalized additive models. Estimated exposure to nighttime environmental noise level in the study population was 58.3±2.2 Leq. Prevalence of oligozoospermia, asthenozoospermia, and severe teratozoospermia were 3.3%, 14.0%, and 10.1%. Highest quartile nighttime noise was associated with 3.5 times higher odds of oligozoospermia (95% CI: 1.18, 10.17) compared to lowest quartile. In men whose noise exposure is in 3rd quartile, odds ratio (OR) of severe teratozoospermia was 0.57 (95% CI: 0.33, 0.98). The OR for 4th quartile noise were toward null. In generalized additive model, the risk of oligozoospermia increases when the nighttime noise is 55 Leq dB or higher. Our study adds an evidence of potential impact of environmental noise on semen quality in men living in Seoul. Additional studies with more refined noise measurement will confirm the finding.

The impact of COVID 19 on air pollution levels and other environmental indicators - A case study of Egypt

The outbreak of coronavirus disease (COVID-19) not only affected health and economics, but also its effect extended to include other aspects, such as the environment. Using Egypt as a case study, this paper presents the impact of COVID-19 pandemic on air pollution levels by studying nitrogen dioxide (NO2), ozone (O3), particulate matter represented in absorbing aerosol index (AAI), carbon monoxide (CO), and greenhouse gas (GHG) emissions. The paper also highlights the impact of COVID-19 pandemic on other environmental indicators including environmental noise, medical and municipal solid wastes. The paper presents the Egyptian COVID-19 story from its different angles including the development of confirmed COVID-19 cases, containment measures from the government, the impact on the country's economy and the national energy consumption so as to effectively evaluate the effect on both the air pollution levels and the other studied environmental indicators. For the other environmental indicators, a strong link was observed between COVID-19 lockdown and the reduction in environmental noise, beaches, surface and groundwater pollution. For environmental noise, this has been confirmed by officially governmental announcements which reported that the level of environmental noise in Egypt was reduced by about 75% during the lockdown period. On the other hand, there are some negative effects, including an increase in medical solid waste (from 70 to 300 ton/day), municipal solid waste, as well as a less efficient solid waste recycling process. For air pollution levels, the data were obtained from National Aeronautics and Space Administration (NASA) and European Space Agency satellite data sets. The data for the lockdown period in 2020 have been extracted and compared to the corresponding months in the selected baseline period (2015–2019) to identify the effect that the lockdown period had on the air pollution levels in Egypt with focus on Cairo and Alexandria governorates. It was found that the AAI decreased by about 30%, the NO2 decreased by 15 and 33% over Cairo and Alexandria governorates, respectively, and that the CO decreased by about 5% over both governorates. In addition, the GHG emissions in Egypt were reduced by at least 4% during the pandemic. In contrast, ozone levels increased by about 2% over Cairo and Alexandria governorates. It can be concluded that the implemented containment measures during COVID-19 pandemic had resulted in both positive and negative environmental impacts. The positive environmental impacts are not sustainable and deterioration on them is expected to occur after the lockdown as it was before the pandemic. Therefore, stricter laws must be enacted to protect the environment in Egypt.

A digital stethoscope with active noise suppression and automatic detection of abnormalities in lung sounds

Auscultation, the action of listening to sounds from the body, typically with a stethoscope, as a part of medical diagnosis remains one of the most common, and cost-effective diagnostic practices but requires a high level of expertise. Although widely practiced, it is undermined by subjectivity in interpretation, limiting the ability to accurately interpret sounds objectively and repeatedly. Frequently, high environmental noise levels render conventional stethoscopes useless. It is also true that substantial experience is required in order to properly diagnose lung abnormalities such as pneumonia and Covid-19. Here we present a digital stethoscope with active noise suppression and an artificial intelligence algorithm (AI) that identifies lung abnormalities with accuracy comparable to trained medical personal. This new line of respiratory diagnostic tools is appropriate for community health workers in under-resourced regions, for chronic respiratory patients in their home, and for medical professionals in noisy clinics, who wish to improve their ability to hear and interpret lung sounds. This conversation will also explore the opportunities and obstacles associated with bringing a product from the lab to the marketplace.

An explanation of the decrease in the earplug noise reduction when combined with an earmuff on an acoustic test fixture

For people working in high noise level environments, typically above 105 dBA, double hearing protection (DHP) systems (earplugs worn in combination with earmuffs) are always recommended. However, it is very difficult to predict the DHP overall sound attenuation due to the complexity of the system. A recent experimental study has shown on human subjects and an acoustic test fixture (ATF) that the noise reduction (NR) of the earplug decreases considerably when an earmuff is worn over it but the reason is still not fully understood. In this work, specially designed experiments using an ATF are proposed in order to explain this observation. The focus is put on the NR of the single earplug and that of the earplug in the DHP system. The respective effects on the DHP attenuation of various sound transmission paths involved in the system (both air-borne and structure-borne) are analyzed by modifying the system coupling conditions or controlling the sound pressure level under the earmuff. This work will help better understand the interactions between the system components and will provide the grounds for developing a prospective numerical model to predict the sound attenuation of a DHP system.

Effect of Exogenous Melatonin Administration in Critically Ill Patients on Delirium and Sleep: A Randomized Controlled Trial.

Introduction Sleep deprivation is a contributor for delirium in intensive care. Melatonin has been proposed as a pharmacological strategy to improve sleep, but studies have shown that the increase in plasma levels of melatonin do not correlate to a beneficial clinical effect; in addition, melatonin's short half-life may be a major limitation to achieving therapeutic levels. This study applies a previously published novel regimen of melatonin with proven sustained levels of melatonin during a 12 h period. In this study, the aim is to determine if such melatonin dosing positively influences on the sleep architecture and the incidence of delirium in intensive care. Methods Single center, randomized control trial with consecutive recruitment over 5 years. Medical and surgical patients were in a recovery phase, all weaning from mechanical ventilation. Randomized allocation to placebo or enteral melatonin, using a previously described regimen (loading dose of 3 mg at 21 h, followed by 0.5 mg hourly maintenance dose until 03am through a nasogastric tube). Sleep recordings were performed using polysomnogram at baseline (prior to intervention) and the third night on melatonin (postintervention recording). Delirium was assessed using the Richmond Agitation and the Confusion Assessment Method Scales. Environmental light and noise levels were recorded using a luxmeter and sound meter. Results 80 patients were screened, but 33 were recruited. Sleep studies showed no statistical differences on arousal index or length of sleep. Baseline delirium scores showed no difference between groups when compared to postintervention scores. RASS scores were 1 in both groups at baseline, compared to zero (drug group) and 0.5 (placebo group) posttreatment. CAM scores were zero (drug group) and 1 (placebo group) at baseline, compared to zero (in both groups) postintervention. Conclusion High levels of plasma melatonin during the overnight period of intensive care cohort patients did not improve sleep nor decreased the prevalence of delirium. This trial is registered with Anzctr.org.au/ACTRN12620000661976.aspx.

Evaluation of exposure to road traffic noise: Effects of microphone height and urban configuration

Noise pollution is a major environmental problem due to its impact on human health and implications for other spheres of society. Since road traffic is the main source of noise pollution, the use of measurement methodologies to accurately determine the environmental noise levels to which the façades of buildings in cities are exposed is an important issue. This paper presents an experimental study in urban environments that uses different configurations to evaluate the influence of the position of the microphone and the parking lanes on the levels of road traffic noise to which the population is exposed.In urban settings in which sound waves propagate without obstacles between the lanes of traffic and the receivers, broadband results for the differences between noise levels measured by microphones placed at heights of 4.0 and 1.5 m showed a significant increase with an increase in the distance between the microphone and sound source of between −0.8 and 0.9 dBA over a range from 2 to 8 m. This difference between the two microphones was greater at points where a lane of parked vehicles was located between the road traffic lanes and the receivers were placed near the façades of building. At the same heights, the broadband difference in sound levels ranged from 2.7 to 4.5 dBA. This acoustic shielding effect due to the presence of parked vehicles started to be relevant in the 250 Hz band and increased progressively with frequency.Taking into account these experimental results and the recommendations in the European Noise Directive, it would be important to apply corrections to sound indicators for road traffic noise that are related to the height of the microphone. Making a distinction between urban configurations with and without lines of parked vehicles between the microphone and the road traffic lanes would be advisable.

Reduction through Brick Wall Barrier and Acoustic Sponge of Environmental Noise Levels from Chiller Cooling System

The aim of this study was to investigate the noise level reduction of the air cooled liquid chiller to the desired levels of environmental noise requisite. Noise control procedures are implemented with various systems to prevent environmental noise disturbances. This paper examines the application of a passive noise control approach to the control of air-cooled liquid chiller noise located in the garden of an official institution. The approach of passive noise control utilizing brick walls with acoustic sponge in the immediate vicinity of the chiller is discussed. When the chiller was covered with a brick wall, the noise level was reduced by 5.5 Leq dBA 1 m away from the nearest residence. However, this reduction could not meet the requirements of legal regulations. Therefore, the inside of brick wall was covered with acoustic sponge. As a result, the ambient noise level where 1m away from the nearest residence to the chiller has been reduced to the background noise levels with a total reduction of about 8.5 Leq dBA. It is shown that, due to the noise produced by the chiller fans and compressors, so as to achieve significantly cognizable levels of noise reduction it is necessary to isolation brick walls with acoustic sponge.

Active Volume Control in Smart Phones Based on User Activity and Ambient Noise.

To communicate efficiently with a prospective user, auditory interfaces are employed in mobile communication devices. Diverse sounds in different volumes are used to alert the user in various devices such as mobile phones, modern laptops and domestic appliances. These alert noises behave erroneously in dynamic noise environments, leading to major annoyances to the user. In noisy environments, as sounds can be played quietly, this leads to the improper masked rendering of the necessary information. To overcome these issues, a multi-model sensing technique is developed as a smartphone application to achieve automatic volume control in a smart phone. Based on the ambient environment, the volume is automatically controlled such that it is maintained at an appropriate level for the user. By identifying the average noise level of the ambient environment from dynamic microphone and together with the activity recognition data obtained from the inertial sensors, the automatic volume control is achieved. Experiments are conducted with five different mobile devices at various noise-level environments and different user activity states. Results demonstrate the effectiveness of the proposed application for active volume control in dynamic environments.

Deep Sensing: Inertial and Ambient Sensing for Activity Context Recognition Using Deep Convolutional Neural Networks.

With the widespread use of embedded sensing capabilities of mobile devices, there has been unprecedented development of context-aware solutions. This allows the proliferation of various intelligent applications, such as those for remote health and lifestyle monitoring, intelligent personalized services, etc. However, activity context recognition based on multivariate time series signals obtained from mobile devices in unconstrained conditions is naturally prone to imbalance class problems. This means that recognition models tend to predict classes with the majority number of samples whilst ignoring classes with the least number of samples, resulting in poor generalization. To address this problem, we propose augmentation of the time series signals from inertial sensors with signals from ambient sensing to train Deep Convolutional Neural Network (DCNNs) models. DCNNs provide the characteristics that capture local dependency and scale invariance of these combined sensor signals. Consequently, we developed a DCNN model using only inertial sensor signals and then developed another model that combined signals from both inertial and ambient sensors aiming to investigate the class imbalance problem by improving the performance of the recognition model. Evaluation and analysis of the proposed system using data with imbalanced classes show that the system achieved better recognition accuracy when data from inertial sensors are combined with those from ambient sensors, such as environmental noise level and illumination, with an overall improvement of 5.3% accuracy.

The effect of parking lots distribution arrangements on environmental noise level for the universities campuses

Recent years witnessed wide increased in private car numbers in Baghdad city. Cause of the lack of public transportations. That leads to increase of demands for car parking, which caused many environmental problems. Recent studies focused on the field of environmental noise levels reduction in cities and educational buildings. This research problem is that there were no obvious studies about the effect of parking lots distribution on environmental noise levels for the universities campuses. The aim of this research is to explore the environmental noise levels resulting from parking lots distribution arrangements within the southern complex at Al-Nahrain University in Baghdad. Software program had been adopted to measure the levels of environmental noise for the educational complex to determine the levels of environmental noise with the future prediction of environmental noise levels in the event of an increase in the number of car parking spaces.

Ambulatory monitoring of Lombard-related vocal characteristics in vocally healthy female speakers.

Speakers typically modify their voice in the presence of increased background noise levels, exhibiting the classic Lombard effect. Lombard-related characteristics during everyday activities were recorded from 17 vocally healthy women who wore an acoustic noise dosimeter and ambulatory voice monitor. The linear relationship between vocal sound pressure level and environmental noise level exhibited an average slope of 0.54 dB/dB and value of 72.8 dB SPL at 50 dBA when correlation coefficients were greater than 0.4. These results, coupled with analyses of spectral and cepstral vocal function measures, provide normative ambulatory Lombard characteristics for comparison with patients with voice-use related disorders.

AORN Position Statement on Managing Distractions and Noise During Perioperative Patient Care

<scp>AORN</scp> Position Statement on Managing Distractions and Noise During Perioperative Patient Care

Niveles de ruido ambiental en dos unidades de cuidados intensivos pediátricos con diferente infraestructura

Aims1) To determine noise levels in two paediatric intensive care units (PICU) of a tertiary hospital and 2) to analyse whether these values comply with the current standards. MethodObservational, descriptive and cross-sectional study carried out in two PICU with different infrastructure: bays separated by curtains and individual bedrooms. A PCE-999 sound level meter was used to determine noise levels, which were registered in decibels (dB). At the same time, an ad hoc data recording document was designed in which we differentiated between each unit (open concept or closed), time of recording. ResultsA total of 330 tests, 72 from open PICUs and 258 from closed PICUs were collected. The noise in the open PICU was 56.74 ± 3.61 decibels versus 50.36 ± 4.71 in the closed PICU, obtaining the highest levels during the morning. DiscussionAs it occurs in other studies, noise levels exceed the allowed limits. At the same time, the main sources of noise in the PICU came from alarms, medical equipment, such as monitors or respirators, and conversations between health professional. ConclusionsThis investigation has shown high levels of environmental noise in the two PICUs analysed. The data obtained indicate that the architectural concept of individual bedrooms may have an impact in decreasing this environmental input.