On-site Noise Research Articles

An On-Site Harmonic Noise Cancellation Antenna With a Multinode Loop for Magnetic Resonance Sounding Measurement

Magnetic resonance sounding (MRS) is a geophysical method to detect aquifers directly in the earth’s magnetic field, which offers the benefit to evaluate groundwater qualitatively and quantitatively. Due to the influence of powerline harmonic noise, the reliability of obtaining the weak MRS signal (10–9 V) is severely limited with a square antenna or a conventional <xref ref-type="fig" rid="fig8" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">figure-8</xref> antenna. To realize the high signal-to-noise ratio (SNR) measurement of groundwater, we first propose a multinode antenna consisting of four <xref ref-type="fig" rid="fig8" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">figure-8</xref> antennas connected around nodes, which has better geometric symmetry and antiphase magnetic dipoles to cancel the magnetic fluxes caused by noise. The simulation results show that the noise suppression effect of the new antenna is better than that of the square antenna and <xref ref-type="fig" rid="fig8" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">figure-8</xref> antenna and is independent of the layout angle. We successfully applied the multinode antenna to test the noise-canceling ability in the urban environment and the detection of field underground aquifers, which verified the superiority of the new antenna in improving the efficiency and the SNR. To be specific, the adoption of this antenna can increase the detection efficiency by 4–8 times and improve the SNR by 10 dB with the same sensitivity compared with the conventional antennas. The utilization of on-site noise suppression characteristic in multinode antennas provides a novel idea for MRS with high SNR, especially in areas with severe noise interference.

Research on the Technical Path of Concrete Building to Net Zero Carbon Pre-fabricated Pre-finished Volumetric Modularization

Global demand for livelihood buildings is still strong, and construction in the traditional way will continue to increase CO2 emissions. The COVID-19 epidemic has led to a shortage of construction personnel sent overseas, and the transformation of the construction industry to a mechanized, prefabricated and digital construction model will alleviate these problems. The paper will develop a low-cost, industrialized, integrated precast and decoration concrete volumetric modular integrated net zero carbon emission building technology mode based on the whole building life cycle evaluation method. This building module product has various functions of zero carbon building at the beginning of the design, and it constitutes zero carbon building after on-site assembly. This technical system has higher production efficiency and better process quality than cast-in-place concrete buildings, and reduces construction time, cost, waste, on-site safety risks, noise and dust. It is the best choice of concrete building to pre-fabricated pre-finished volumetric construction technology transformation, is the construction industry to help "Two carbon" climate goal to achieve one of the green technology path.

A missense variant rs2585405 in clock gene PER1 is associated with the increased risk of noise-induced hearing loss in a Chinese occupational population

ObjectiveTo investigate the potential association of cochlear clock genes (CRY1, CRY2, PER1, and PER2), the DNF gene (brain-derived neurotrophic factor), and the NTF3 gene (neurotrophin3) with susceptivity to noise-induced hearing loss (NIHL) among Chinese noise-exposed workers.MethodsA nested case–control study was performed with 2056 noise-exposed workers from a chemical fiber factory and an energy company who underwent occupational health examinations in 2019 as study subjects. Propensity score matching was conducted to screen cases and controls by matching sex, age, and the consumption of tobacco and alcohol. A total of 1269 participants were enrolled. Then, general information and noise exposure of the study subjects were obtained through a questionnaire survey and on-site noise detection. According to the results of audiological evaluations, the participants were divided into the case group (n = 432, high-frequency threshold shift > 25 dB) and the matched control group (n = 837, high-frequency threshold shift ≤ 25 dB) by propensity score matching. Genotyping for PER1 rs2253820 and rs2585405; PER2 rs56386336 and rs934945; CRY1 rs1056560 and rs3809236; CRY2 rs2292910 and rs6798; BDNF rs11030099, rs7124442 and rs6265; and NTF3 rs1805149 was conducted using the TaqMan-PCR technique.ResultsIn the dominant model and the co-dominant model, the distribution of PER1 rs2585405 genotypes between the case group and the control group was significantly different (P = 0.03, P = 0.01). The NIHL risk of the subjects with the GC genotype was 1.41 times the risk of those carrying the GG genotype (95% confidence interval (CI) of odds ratio (OR): 1.01–1.96), and the NIHL risk of the subjects with the CC genotype was 0.93 times the risk of those carrying the GG genotype (95%CI of OR: 0.71–1.21). After the noise exposure period and noise exposure intensities were stratified, in the co-dominant model, the adjusted OR values for noise intensities of ≤ 85 was 1.23 (95%CI: 0.99–1.53). In the dominant model, the adjusted OR values for noise exposure periods of ≤ 16 years and noise intensities of ≤ 85 were 1.88 (95%CI: 1.03–3.42) and 1.64 (95%CI: 1.12–2.38), respectively.ConclusionThe CC/CG genotype of rs2585405 in the PER1 gene was identified as a potential risk factor for NIHL in Chinese noise-exposed workers, and interaction between rs2585405 and high temperature was found to be associated with NIHL risk.

Analyzing transportation noise during the pandemic.

The COVID-19 pandemic has introduced new challenges in the approach to many types of projects in the field of acoustical consulting. An important one being the impact on how transportation noise studies are conducted, in particular on-site noise measurements and subsequent computer modeling. The pandemic has affected roadway, railway, and aircraft travel, and consequently the noise generated by these transportation noise sources. This raises questions about the methods used to determine existing and future transportation noise impact upon residential sites. After a year into the pandemic, it appears that postponing an analysis is no longer feasible and that the need for an adaptable method of analysis is required to meet jurisdictional transportation noise analysis requirements. How should these studies be completed during this time in which it is highly likely that roadway, railway, and aircraft volumes are not what they were pre-pandemic? How or even should on-site noise measurements be taken? Will the local jurisdictions accept the studies completed during the pandemic? When will roadway, railway, and airport volumes be back to pre-pandemic levels, or will they ever be back to that volume? Will there be a significant impact on noise? This paper will follow the process used to complete transportation noise studies during the pandemic, which involved creatively adapting known methods to address these new questions while working closely with local jurisdictions, providing the education and guidance needed for them to comfortably review studies so that the transportation noise component of site approval does not slow down residential projects.

Noise codes and acoustical design criteria for distribution facilities

Distribution and warehouse-type facilities are routinely constructed all over the country and the world. On-site noise sources for this type of facility include heavy trucks, delivery vehicles, and rooftop HVAC equipment. Stationary noise is often more clearly regulated than mobile noise sources. To protect the public, appropriate criteria need to be established for all sources. Some jurisdictions have quantitative regulatory limits in place that may be used as design criteria while others may have less helpful qualitative code language or no noise code at all. A review of common metrics found throughout the U.S. is presented to understand code language that appropriately protects the public for specific sources. In addition, it is useful to analyze and discuss common criteria applied in the absence of quantitative code limits.

Noise Reduction by Rail Damper Tunable for Individual Rails in Curve

Tuned mass rail dampers are cost effective for the mitigation of the airborne noise and vibration with the ability to be tuned for individual site. TMDs have been developed and installed at a single rail in a curve tunnel and achieve more than 4dB(A) noise reduction in many cases. According to the on-site noise reduction performance during damper installation, half, one, two or three dampers can be installed at each spacing between two baseplates. TMDs with only half-installation provides more than 10dB reduction at vertical pin-pin resonance (~1kHz). With the standard installation, they provide the strong damping to half the corrugation growth rate. The stick-slip phenomena which causes the corrugation will be affected by the damping effect from TMDs. On the other hand, they can also be tuned to the low-frequency (p2 resonance) for grandborne noise control. The high reduction of the grand borne noise proved our claim for effectiveness of the TMDs besides many other studies on the other parameters like the type of the baseplates or the soil types. According to the test results TMDs achieve strong performance in different range of the frequencies.

RASTER DATA BASED AUTOMATED NOISE DATA INTEGRATION FOR NOISE MAPPING LIMITING DATA DEPENDENCY

Abstract. Noise has become a recurrent problem worldwide. Road traffic noise studies in India are fewer and restricted only to the metropolitan areas. These studies focused on recording, monitoring, analysis, modelling, and mapping. The major concern is with the onsite collection of vehicular noise data from road sites. Road traffic noise maps have been generated by using traditional techniques that involve the collection of road traffic noise by experts. There are negligible studies in the area of automated noise generation for road traffic noise. In this paper, the study examines the problems that an individual is facing in collecting onsite noise data. Onsite Noise data collection with Sound Pressure level increases the delay. A noise map is a graphical representation of the spatial dissemination in a given area for a characterized period. Developing any geospatial application requires the collection of geospatial data and attribute information. Open-source geospatial data are largely available today in the form of Map APIs. Making a model to extract spatial and attribute information from it can offer an easy solution for urban applications, without needing a separate collection of geospatial or attribute information. Google raster maps for city roads and surrounding buildings in UP are tried to be used to extract roads, buildings, vehicles, trees, etc. Various geometrical setups of vehicles in several similar road segments are tried classified using ML algorithms. Vehicular clusters in road segments are classified into 3 categories, high, medium, and low. Further characterized in terms of the range of noise spectra associated with it incorporating field data. These noise scenes are then utilized to predict the various types of simulated noise maps predicted around the road segments on an instantaneous scale, with an estimation of accuracy.

Influence of architectural layouts on noise levels in Danish emergency departments

This study aims to evaluate the effects of architectural layouts of emergency departments on activity patterns/work routines and consequent noise levels. Three Danish hospitals' emergency departments that had different layouts were investigated via on-site noise measurements over three days and observations of noisy activities. The time-averaged noise levels in the three emergency departments turned out to be significantly different, ranging from 50 to 59 dBA. During the observation of noisy activities, the noise levels and occurrences of individual activities were noted and correlated with the long-term measurements. Major noise sources that have high correlations with the three-day noise levels are identified as loud staff communication and noise from alarms/electronic devices. Potential remedies are suggested in connection to the emergency departments’ architectural layouts. Especially unnecessarily loud communication between medical staff and loud and frequent equipment/patient transportation noise need to be improved for more comfortable acoustic environments.

Effects of aircraft noise on residents nearby a Malaysian airport

In this study, the effects of aircraft noise on the residents living nearby Sultan Ismail Petra Airport, Kelantan, Malaysia, were investigated. A questionnaire survey involving 60 participants revealed that 46.67% agreed that aircraft noise is a source of disturbance in their daily routine. On-site noise level measurements were carried out over a 2-week period at seven locations (P1–P7) surrounding the airport, where each location represents a different distance from the noise source. The daily average noise levels were within 50–65 dB(A), which exceeded the World Health Organization’s recommended maximum indoor noise level and recommended maximum outdoor noise level of 35 and 55 dB(A), respectively. However, the daily average noise levels were lower than permissible exposure limit of 90 dB(A). Based on the results, it can be concluded that exposure to the aircraft noise may affect the quality of life of nearby residents in the long term.

Environmental noise assessment of Bhandara City in the adversity of COVID-19 pandemic: A crowdsourcing approach

Abstract The strict enforcement of lockdown in India and worldwide to contain the spread of the COVID-19 pandemics has brought a signiicant change in the environmental quality, particularly in cities. The study deliberates an overview of the status of the ambient noise quality of the tier-2 city Bhandara, India, for lockdown and posts lockdown circumstances. In the course of lock-down, it is unfeasible to walk out with standard instruments for onsite noise monitoring with the conventional method in such adversity. Make use of the crowdsourcing approach proves to be the best alternative for collecting noise data with the help of an android-based noise application, łNoise Tracker.ž On assessing gathered data, it ascertained that the noise levels deplete by 8.0 dB during the lockdown. Results indicated that the average noise levels in more than 80% of the locations are lowered during lock-down compared to post lockdown in Bhandara City. A signiicant reduction in average noise levels at all sites during the lockdown period attributing to limiting in the road, rail, and other traic movements. The study is an exclusive example of ordinary people from tier-2 city indulging in environmental scientiic research. The study also visualizes the noise pollution scenario of lockdown and post lockdown periods using noise maps.

Construction of Online Monitoring System for Track Safety and its Vibration and Noise

In accordance with the requirements of intelligent and scientific maintenance and repair for rail transit, the on-line monitoring and intelligent assessment technologies for infrastructure safety as well as vibration and noise indexes are studied. In connection with the line status of the Shanghai rail transit network, typical line sections are selected to lay out the online status monitoring equipment so as to track health and safety indexes of rails and real-time noise and vibration levels. By means of online real-time data collection and synchronous analysis technology, the Shanghai rail transit online monitoring system for track safety status and its vibration and noise takes shape, thereby achieving real-time monitoring for on-site vibration and noise as well as safety status, and providing assistant decision-making reports in connection with relevant index systems and in accordance with relevant time periods.

Analysis Technology of Tennis Sports Match Based on Data Mining and Image Feature Retrieval

Tennis game technical analysis is affected by factors such as complex background and on-site noise, which will lead to certain deviations in the results, and it is difficult to obtain scientific and effective tennis technical training strategies through a few game videos. In order to improve the performance of tennis game technical analysis, based on machine learning algorithms, this paper combines image analysis to identify athletes’ movement characteristics and image feature recognition processing with image recognition technology, realizes real-time tracking of athletes’ dynamic characteristics, and records technical characteristics. Moreover, this paper combines data mining technology to obtain effective data from massive video and image data, uses mathematical statistics and data mining technology for data processing, and scientifically analyzes tennis game technology with the support of ergonomics. In addition, this paper designs a controlled experiment to verify the technical analysis effect of the tennis match and the performance of the model itself. The research results show that the model constructed in this paper has certain practical effects and can be applied to actual competitions.

Exploratory analysis of noise reduction solutions in a psychiatric ward using beamforming techniques

The world health organization recommendations related to a psychiatric ward for sound pressure level measurements overtime are not to exceed 30 and 35 dBA, respectively. However, no published study results since 1975 have reported full compliance within a hospital. Hospitals are a stressful work environment regardless of the noise level that averages between 53 and 58 dBA. Unique working solutions offered by design architects and insurance companies to reduce noise conditions in a physiological health facility are not transferable to psychiatric units that are operating as a behavioral health facility. This study reports on an exploratory analysis of the noise reduction strategies within a psychiatric ward. Architecturally and electronically implemented noise mitigation solutions are used to minimize noise annoyance, which is related to the noise sensitivity of the patient and staff. Sound mapping and noise source localization are conducted utilizing beamforming techniques. Onsite noise measurements in time and frequency domain provide design opportunities for isolating patient rooms from noise by the public and staff working areas. The impact of working solutions on speech privacy and annoyance is determined. The results contribute to a more extensive database and opportunities toward improvement in design guidelines for psychiatric wards and a positive influence on the hospital soundscape.

A monitoring system for spatiotemporal electrical self-potential measurements in cryospheric environments

Abstract. Climate-induced warming increasingly leads to degradation of high-alpine permafrost. In order to develop early warning systems for imminent slope destabilization, knowledge about hydrological flow processes in the subsurface is urgently needed. Due to the fast dynamics associated with slope failures, non- or minimally invasive methods are required for inexpensive and timely characterization and monitoring of potential failure sites to allow in-time responses. These requirements can potentially be met by geophysical methods usually applied in near-surface geophysical settings, such as electrical resistivity tomography (ERT), ground-penetrating radar (GPR), various seismic methods, and self-potential (SP) measurements. While ERT and GPR have their primary uses in detecting lithological subsurface structure and liquid water/ice content variations, SP measurements are sensitive to active water flow in the subsurface. Combined, these methods provide huge potential to monitor the dynamic hydrological evolution of permafrost systems. However, while conceptually simple, the technical application of the SP method in high-alpine mountain regions is challenging, especially if spatially resolved information is required. We here report on the design, construction, and testing phase of a multi-electrode SP measurement system aimed at characterizing surface runoff and meltwater flow on the Schilthorn, Bernese Alps, Switzerland. Design requirements for a year-round measurement system are discussed; the hardware and software of the constructed system, as well as test measurements are presented, including detailed quality-assessment studies. On-site noise measurements and one laboratory experiment on freezing and thawing characteristics of the SP electrodes provide supporting information. It was found that a detailed quality assessment of the measured data is important for such challenging field site operations, requiring adapted measurement schemes to allow for the extraction of robust data in light of an environment highly contaminated by anthropogenic and natural noise components. Finally, possible short- and long-term improvements to the system are discussed and recommendations for future installations are developed.

De-noising of partial discharge signal using wavelet transform for GIS under HVDC

Abstract Detection and analysis of partial discharge (PD) have been regard as the most effective method for condition monitoring and asset management of gas-insulated structures (GIS) in the power system. However, PD detection sensitivity and accuracy are greatly influenced by on-site noise and interference, resulting in failures in PD severity assessment, defect identification or localization. Although de-noising of PD signal under AC was well studied, related investigations under DC have not been carried out. With the rapid development of HVDC technology, it is a new challenge to eliminate noise from PD signal under DC for diagnosis of related power facilities. Therefore, this paper dealt with the discrimination of PD signal based on wavelet transform (WT) techniques for HVDC GIS, aiming to improve the sensitivity and accuracy of insulation diagnosis. Experimental setup was configured to generate PD signal under DC and four types of artificial defects were fabricated to simulate typical insulation defects in GIS. The WT techniques were used to discriminate PD pulse sequences from background noise, amplitude modulation radio interference, non-sinusoidal noise, and switching impulse and the effectiveness was compared with a high-pass filter.

Local-field-induced current noise in shape-limited self-doped polyaniline

Electronic noise generators are an essential component of molecular neuromorphic devices. To realize molecular noise generators with a high degree of freedom for design and integration into molecular devices, the utilization of the local electric field for the modulation of electrical conduction via a shape-limited conductive polymer is one promising strategy. Herein, a molecular noise generator composed of thin self-doped polyaniline (SPAN) lines is reported. SPAN lines fabricated via fountain pen lithography on SiO2/Si substrates were found to generate current noise upon laser irradiation. This current noise exhibited white-noise-like power spectral density in the frequency range of 1–25 Hz and was independent of temperature. Multiple independent noise generation on the same substrate was also successfully demonstrated. The present results indicate that the noise generation mechanism involves the local modulation of hopping conduction via SPAN lines owing to the spatial proximity of the conduction path in the SPAN line to the surface photovoltage region of the SiO2/Si interface. This on-site random noise generation in shape-limited conductive polymers is expected to be beneficial for the realization of molecular neuromorphic devices.

Noise Characteristics of Distribution Power Transformers under Field Load Conditions

In order to investigate the influence of load conditions on the noise characteristics of distribution power transformers, a platform in semi-anechoic room is designed for on-site transformer noise simulation. Transformer noises in balanced, unbalanced and harmonic load conditions are tested, respectively. The spectral distributions and A-weight sound pressure levels (SPLs) are compared to investigate the discrepancy caused by various load conditions. The result shows that the transformer noise is relevant with unbalanced load. Harmonic content is found to have obvious influence on the noise level of distribution power transformer. When harmonic load current is applied, the noise level of distribution power transformer increase obviously. The results can be referenced for the field noise and vibration control of distribution power transformers.

Anomaly Detection for Partial Discharge in Gas-Insulated Switchgears Using Autoencoder

In this article, we propose a new anomaly detection method to detect the partial discharge in a gas-insulated switchgear. An autoencoder was used for anomaly detection and was modeled on the one-class classification problem. Based on the one-class classification scenario, in which the training data exploited the noise data only, the proposed autoencoder learned the low-dimensional latent information from the high-dimensional space of the input signal. Then, the reconstruction error was used as a fault indicator, and the threshold was determined using the partial discharge data. The performance of the proposed AE was verified by on-site noise and PRPD experiments, using an online UHF PD monitoring system in the real-world environment. The results showed that the proposed autoencoder not only achieved 86.75% detection performance for the on-site noise and partial discharge data in gas-insulated switchgears but also allowed better detection performance than the one-class support vector machine learning procedure by 40.5%.

Comparative Analysis of Performance of Porous Asphalt Pavement and SMA Pavement Based on Deck Pavement Structure

Viaducts are more and more widely used in China. How to ensure the safety of the bridge deck has become a hot issue of concern? Based on the above problems, the application of porous asphalt pavement in bridge deck pavement is also increasing. Based on the porous asphalt pavement project of Shijiazhuang City Ring Road (West Second Ring of Heping West Road), the performance differences between porous asphalt pavement and stone matrix asphalt pavement were studied. By comparing the gradation characteristics and performance of porous asphalt mixture and stone matrix asphalt mixture, the advantages and disadvantages of the two mixtures in road performance were analyzed. At the same time, we carried out on-site braking test, noise test and long-term temperature monitoring on two types of pavement. By comparing the test results, we thought that porous asphalt pavement could reduce the braking distance by up to 7 m in mid-to heavy rain weather, and porous asphalt pavement could reduce 2-6 dB noise, Porous asphalt pavement has better cooling effect than stone matrix asphalt pavement, and the higher the external temperature was, the better the cooling effect of porous asphalt pavement was, and it could reduce 6-8°C in summer. Through the test comparison, we draw the conclusion that the pavement performance of porous asphalt pavement is better than that of stone asphalt pavement.

Measurement and analysis of sound radiation from coherently vibrating shunt reactors

In parallel with the rapid development of ultra-high voltage (UHV) power transmission systems, noise contamination radiated from UHV shunt reactors is becoming an urgent concern. This investigation explored the distributed structural vibration of reactors and their near-field and far-field sound radiation characteristics based on a thorough on-site measurement and a combined numerical method. The proposed method could realize sound field reconstruction of on-site shunt reactors by directly measuring their surface vibration, thus avoiding complex modelling with fluid-structure interactions and multi-physics problems. Furthermore, the combined method was utilized to investigate the effect of acoustical environments upon reactors’ sound radiation. The results show that reflection boundaries composed of firewalls among reactor units could introduce a higher noise level in the parallel radiation region due to their influence on the sound source directivity. Finally, the sound power levels of the on-site reactors were derived from the constructed sound field, which could avoid on-site background noise concerns in the current executive standards.