日本語における会話音声の音圧レベル測定

Risks to the Hearing of Musicians – Subjective and Objective Evaluation of Sound Exposures in a Non-Professional Orchestra

The train noise in station (TNIS) can annoy passengers and reduce the speech intelligibility of the public address system in a station. Thus clarifying the acoustical characteristics of TNIS is important for the comfort and safety. Noise level was evaluated the equivalent continuous sound pressure level (LAeq). The sound diffuseness was evaluated by the interaural cross-correlation coefficient (IACC) from the interaural cross-correlation function. The pitch and pitch strength was evaluated by the delay time (t1) and amplitude (f1) of the first peak of the autocorrelation function. The LAeq and IACC of the TNIS in the underground station were higher and lower, respectively, than those in the ground station. The t1 and f1 of the TNIS in the underground station were stable and lower, respectively, than those in the ground station. When the train came into the station, the LAeq of the TNIS at the island platform were higher than that at the side platform. The result suggests that the underground island platform, which is one platform at the center and the rail tracks on the both sides, needs improvement in particular although it is most frequently adopted as newly constructed stations in Japan.

Wind turbine noise referred to as “swishing sound” causes annoyance due to the amplitude modulation of the noise aerodynamically generated from blades. For the propagation characteristic of sound emitted from blade, the noise can be heard differently from place to place. For that reason, many studies on numerical index evaluating annoyance caused by wind turbine noise have been examined. The results, however, showed little correlation with change of equivalent continuous sound pressure level. In the present study, twenty-eight stimuli created by numerical simulation for the test were provided and thirty-two subjects assessed noise-induced annoyance. Additionally, a correlation analysis between sound descriptors and subjective annoyance was performed by using regression analysis with SAS software. This study shows that the maximum sound pressure level with fast time A-weighting (LAFmax) explains well the annoyance characteristics compared to the other descriptors considered.

BackgroundExisting evidence suggests that psychiatric patients are highly noise sensitive, and that noise exposure increases the risk for adverse mental health outcomes, such as psychiatric hospitalizations and even suicide. To investigate acute effects of noise in this vulnerable population, we assessed short-term associations between fighter jet noise and on-demand sedative and analgesic drug administrations in a psychiatric clinic located close to a military airfield in Switzerland. MethodsWe applied a case time series analysis with an hourly time resolution using distributed-lag models. Analysis was adjusted for long-term and seasonal trends, day of week, time of day, time-varying weather conditions and the week of stay. Noise exposure (hourly A-weighted equivalent continuous sound pressure levels (LAeq)) was modelled using detailed flight plans and noise footprints for different fighter jet and route combinations. Outcome data were available from the clinic’s records. OutcomesDuring the study period (06/2016–12/2021), 23,486 flights occurred. 5,968 clinical stays with a median length of 41 days (IQR: 28d, 50d) were recorded. The odds ratio (OR) for medication administration over the lag period of 3 hours after exposure was 1.016 (95 %CI: 1.006, 1.026) per 10 dB LAeq for sedatives and 1.032 (95 %CI: 1.016, 1.048) per 10 dB for analgesics. Effects were larger in multimorbid patients. InterpretationCase time series analysis is a novel method to investigate transient associations in observational data while minimizing risk of bias. Using an objectively recorded outcome measure, our results demonstrate that psychiatric patients are a vulnerable population, in which noise exposure can lead to symptom exacerbations and adverse events.

This study estimates the equivalent continuous sound pressure level (Leq) during peak daily periods (‘rush hour’) along the New Klang Valley Expressway (NKVE) in Shah Alam, Malaysia, using a land use regression (LUR) model based on machine learning, statistical regression, and geographical information systems (GIS). The research utilises two types of soft computing methods including machine learning (i.e., decision tree, random frost algorithms) and statistical regression (i.e., linear regression, support vector regression algorithms) to determine the best approach to create a prediction Leq map at the NKVE in Shah Alam, Malaysia. The selection of the best algorithm is accomplished by considering correlation, correlation coefficient, mean-absolute-error, mean-square-error, root-mean-square-error, and mean absolute percentage error. Traffic noise level was monitored using three sound level meters (TES 52A), and a traffic tally was done to analyse the traffic flow. Wind speed was gauged using a wind speed meter. The study relied on a variety of noise predictors including wind speed, digital elevation model, land use type (specifically, if it was residential, industrial, or natural reserve), residential density, road type (expressway, primary, and secondary) and traffic noise average (Leq). The above parameters were fed as inputs into the LUR model. Additional noise influencing factors such as traffic lights, intersections, road toll gates, gas stations, and public transportation infrastructures (bus stop and bus line) are also considered in this study. The models utilised parameters derived from LiDAR (Light Detection and Ranging) data, and various GIS (Geographical Information Systems) layers were extracted to produce the prediction maps. The results highlighted the superior performances by the machine learning (random forest) models compared to the statistical regression-based models.

Noise levels in a cardiac surgical intensive care unit: a preliminary study conducted in secret.

Experimental study to measure the transmission loss of double panel natural fibers

This study aims to analyze the factors of indoor environment on occupants’ health and comfort by post-occupancy evaluation (POE) and to accumulate the fundamental data of occupants’ behaviour in relation to indoor environment, in an effort to ascertain the optimal building energy management system (BEMS). For this purpose, indoor temperature, relative humidity, vertical temperature distribution, air velocity, predicted mean vote (PMV), radiant temperature, outdoor temperature, and humidity were measured for evaluating thermal environment for nearly 2 years. Indoor air contaminants, such as PM10, CO2, formaldehyde, and volatile organic compounds (VOCs) were measured in the building and at outdoor locations. Working plane illuminance, window luminance, and the equivalent continuous a-weighted sound pressure level (Leq) were also monitored. In addition, the occupants in the intelligent office building were surveyed regarding the indoor environmental quality via the intranet. Results showed that all indoor environmental factors satisfied the recommendation, except the indoor relative humidity and PMV. The physical factors of thermal environment had been stable since two months after it was built. However, it should be necessary to improve the sound privacy caused by low background noise, seasonal air-conditioning for appropriate humidity, air freshness, and Video Display Terminal (VDT) glare in order to reduce the level of occupants’ annoyance.

Quiet communities, which are encouraged to maintain a harmonious and tranquil urban living environment, have attracted increasing attention in designing method in recent years. The relevant residential standards specify quiet thresholds with regard to noise pollution issues. However, the variation in height across floors of high-rise buildings and variation with time in sound environments have not been examined in detail. The city of Shanghai experienced a city-wide lockdown to control the spread of COVID-19, showing evidence of quietness and a significant reduction in anthropogenic noise. Here, we conducted noise monitoring in a 14-storey apartment building that was surrounded and shielded by other buildings in a typical urban community during and after the lockdown. The mean value of all 14 floors of equivalent continuous A-weighted sound pressure level (LAeq,T) after lockdown was systematically greater than that during lockdown, with differences of 3.6 and 3.1 dB during the daytime and night-time periods, respectively. We suggest that in practice, it is useful to consider the specific floor or time of day.

Effects of high-speed railway noise on the synaptic ultrastructure and phosphorylated-CaMKII expression in the central nervous system of SD rats

Effects of auditory and tactile warning on response to visual hazards under a noisy environment

Sleep-wake disorders are common after stroke and negatively affect stroke outcome. Environmental factors such as noise and light exposure can perturb sleep quality and destabilise circadian rhythm. This study aimed to quantify light and noise exposure of hospitalised patients in a stroke unit and assessed compliance with recommended guidelines. Between July and August 2021, noise and light levels were measured in the former stroke unit of the Inselspital Bern. Noise exposure was assessed via the equivalent continuous A-weighted sound pressure level (LAeq), light exposure was assessed using melanopic equivalent daylight illuminance. World Health Organization recommended noise levels (30dB at night and 35dB during the day) were constantly exceeded. Door beds were significantly noisier than window beds during evenings (53±3.3dB vs 48.6±3.5dB) and during nighttime (43.4±4.0dB vs 39.5±4.5dB). Minimal daytime illuminance of 250 lx melanopic equivalent daylight illuminance was hardly ever reached at door beds (15±30min) but was reached for about 3h throughout the day at window beds (186±108min). The highest quantity of illuminance was reached during late evening hours (18-22h) for both window and door beds rather than in the mornings (6-10h). These observations suggest that the setting of monitored stroke units is unfavourable for sleep because of insufficient light and excessive noise exposure. Further studies are needed to confirm this observation and assess the associated effects on sleep-wake functions and stroke outcome.

To evaluate the effect of a newly constructed intermediate care unit (IMCU) on noise levels, lighting conditions, and delirium incidence. Sound pressure levels, including the equivalent continuous A-weighted sound pressure level (LAeq), background sound pressure level (LA90), peak sound pressure level (LA10), and lighting conditions expressed as melanopic equivalent daylight illuminance (melanopic EDI) were measured continuously for multiple days in an IMCU in Wil, St. Gallen, Switzerland before and after relocation. Delirium incidence was tracked before and after relocation. Both units constantly exceeded the World Health Organization recommended limits for noise. However, relocation decreased background noise levels (LA90) during day and night ( P = 0.027, P = 0.016, respectively). Lower sound pressure levels (LAeq) were also measured at the new nursing station. Lighting conditions were adequate before relocation but failed to meet international standards throughout the day. In the newly constructed IMCU, lighting conditions worsened (lower melanopic EDI compared to the old IMCU; P < 0.001), and recommended daytime illuminance levels were never achieved. No differences in delirium incidence were observed after relocation ( P > 0.05). The observations in this first-ever study suggest unexpected noise and lighting conditions in an IMCU and a central role of architectural factors. Further studies are needed to determine the impact of noise, light, and architectural characteristics in IMCUs on delirium and other significant clinical outcomes. In hospitals, architectural characteristics such as large south-facing windows and other factors influencing light and noise, such as spatial organization and staff awareness, should be considered to promote sleep-wake circadian functions and thus enhance patient comfort and recovery.

Exploration of environmental noise in Saharan oases on the basis of urban configurations: City of Biskra datasets

A study on the control indices and emission limits of substation noise