• Journal of Technologic Dentistry
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• 제36권2호
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• pp.111-118
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• 2014

Purpose: Production of dental prosthesis by a dental technician causes a loud noise. Thus, we investigated stress of dental technicians due to a noise using a structured questionnaire. Methods: A survey was conducted on working dental technicians across the country from July 2013 to November 2013; among 200 sets of survey distributed, 166 were completed and returned, and excluding the 11 that deemed unsuitable, 155 sets were used for statistics. The program SPSS 19.0 was used to analyze the correlation among the collected data. Results: The stress of noise was found to be 2.83/5 points (2.93/5 for physical stress, 2.72/5 for emotional stress). Recognition of noise was found to be 2.71/5 points (3.39/5 for recognition of noise, 2.64/5 for accidents caused by noise, 2.29/5 for experiencing disability due to noise). For general items, the highest stress were shown for the following catogories: by gender, females (p=.008); by position, chief engineer (p=.033); by monthly pay, 2.51M-3.0M KRW (p=.023); by interior comfort, 'very unpleasant' was the highest recognized (p=.014). For the effect of time exposed to noise, its stress (p=.000) and recognition (p=.000) rose with increase of time. Conclusion: Dental technicians performs tasks in work environments exposed to extreme noise. This research attempts to re-emphasize the necessity for improving the work environment for noise and provide measures of blocking noise and precaution.

• International conference on construction engineering and project management
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• The 8th International Conference on Construction Engineering and Project Management
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• pp.237-242
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• 2020

Construction noise is among the most critical stressors that adversely affect the quality of life of the people residing near construction sites. Many countries strictly regulate construction noise based on sound pressure levels, as well as timeslots and type of construction equipment. However, individuals react differently to noise, and their tolerance to noise levels varies, which should be considered when regulating construction noise. Although studies have attempted to analyze individuals' stress responses to construction noise, the lack of quantitative methods to measure stress has limited our understanding of individuals' stress responses to noise. Therefore, the authors proposed a quantitative stress measurement framework with a wearable electroencephalogram (EEG) sensor to decipher human brain wave patterns caused by diverse construction stressors (e.g., worksite hazards). This present study extends this framework to investigate the feasibility of using the wearable EEG sensor to measure individuals' emotional stress responses to construction noise in a laboratory setting. EEG data were collected from three subjects exposed to different construction noises (e.g., tonal vs. impulsive noises, different sound pressure levels) recorded at real construction sites. Simultaneously, the subjects' perceived stress levels against these noises were measured. The results indicate that the wearable EEG sensor can help understand diverse individuals' stress responses to nearby construction noises. This research provides a more quantitative means for measuring the impact of the noise generated at a construction site on neighboring communities, which can help frame more reasonable construction noise regulations that consider various types of residents in urban areas.

• Journal of Physiology & Pathology in Korean Medicine
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• 제21권2호
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• pp.523-527
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• 2007

Previous studies reported that exposure to noise during pregnancy adversely influenced the development of the fetus and neonate. In Oriental medicine, medications based on Angelicae gigantis radix have been known to be of efficacy in the treatment of various diseases. c-Fos, an immediate early gene whose expression is sometimes used as a marker for stimulus-induced changes in the metabolic activity of neurons. In the present study, the influence of postnatal Angelicae gigantis radix administration on c-Fos expression in the each region of hippocampus of offspring rats with prenatal noise stress during pregnancy was investigated. From the present results, exposure to the prenatal stress during pregnancy enhanced c-Fox expression, whereas exposure to postnatal Angelice gigantis radix suppressed c-Fos expression in the offsprings with prenatal noise stress during pregnancy. Based on the present study, Angelicae gigantis radix may provide new therapeutic opportunities as an agent to counteract the effects of prenatal noise stress- induced hippocampal dysfunction, and may be useful in the treatment of psychiatric problems in children of mothers who have experienced noise stress during pregnancy.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• 제33권4호
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• pp.464-470
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• 2023

Objectives: This study evaluated occupational exposures to noise and heat stress during routine non-outage works in three coal-fired power plants in the Republic of Korea. Methods: The data were collected during the summer of 2020. Full shift noise exposure of 52 workers were measured using noise dosimeters. Heat stress of 16 worksites were measured for 70 minutes using wet-bulb globe temperature monitors. Results: The noise dosimetry results revealed time-weighted averages that ranged from 47.5 to 88.9 dBA. 2 out of 52 noise measurements exceeded 85 dBA. Based on the arithmetic mean, the coal service group showed the highest level at 80.2 dBA by job tasks. Noise exposures exceeding 85 dBA were measured in the coal service and plant operator group. Heat stress index measurements ranged from 20.3℃ to 37.2℃. 1 out of 9 indices measured in coal facilities and 4 out of 7 indices measured in boiler house exceeded 1 hour TWA during moderate work. Heat stress indices measured from boiler houses were significantly higher than those measured from coal equipment. Conclusions: The results show that overexposure to noise and heat stress may be encountered during routine non-outage work activities in coal-fired power plants. Appropriate actions should be taken to reduce future health outcome from occupational exposure to noise and heat stress in the industry.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 한국감성과학회 1999년도 춘계학술발표논문집 논문집
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• pp.127-132
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• 1999

Cardiovascular, respiratory and electrodermal responses to acute stress episodes modeled by combined presentation of intense white noise and performance of word recognition task with noise background were studied in 15 college students. Experimental procedure consisted in sessions with white noise, word recognition task presentation with noise background and test with noise background. Recorded physiological variables were analyzed in terms of their sensitivity to detect activation of sympathetic and parasympathetic branches of autonomic nervous system and thus reflect autonomic arousal level during shout-term stress-inducing experimental manipulations. It was shown that performance of effortful mental task with noise background elicited significant physiological responses typical for active coping behavior, namely electrodermal arousal and increased cardiovascular activity. this response profile was more profound as compared to white noise only or attending task in noise background. However, all physiological responses were mostly phasic, without long-term tonic changes, since almost all variables recovered to their initial baseline levels, suggesting that dominant autonomic mechanisms in transient acute stress episodes were of parasympathetic nature (withdrawal in stress with subsequent activation in restoration period), while sympathetic contribution was not long-lasting. Nevertheless, increased number of stressors and their longer exposure may result in higher profile of tonic sympathetic arousal and reduced functional role of vagal mechanisms in autonomic balance regulation.

• Journal of Home Health Care Nursing
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• 제24권3호
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• pp.316-324
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• 2017

Purpose: This study was conducted to investigate the effect of white noise on sleep quality, depression, and stress in college students. Method: This study was designed a randomized controlled design to measure the effect of white noise on college students' sleep quality, depression, and stress. Data collection was conducted from May 15, 2017 to June 5, 2017. The subjects were randomly assigned to 27 college students and 28 control volunteers. Data analysis was done using SPSS 23.0 Windows program. Results: The experimental and control groups were homogeneous in general characteristics and study variables. The white noise group showed statistically significant effects on stress(t=-2.25, p=.015) and sleep quality(t=0.65, p<.001). Conclusion: This study confirms that white noise has a positive effect on stress and sleep of college students. Based on these results, it is expected that further research will be conducted on systematic and differentiated white noise mediation.

• Journal of the Korean Society for Nondestructive Testing
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• 제10권1호
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• pp.91-95
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• 1990

Welding residual stress was measured by Barkhausen noise method. The calibration experiment was done for the quantitative analysis. The specimen for the calibration experiment must has the same thermo-mechanical history as the actual material to be tested. The Barkhausen noise were analysed by the pulse-height distribution. The results show that the distribution and magnitude of welding residual stress from Barkhausen noise method are in good agreement with those from blind hole method.

• Journal of Environmental Health Sciences
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• 제49권6호
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• pp.353-361
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• 2023

Background: Noise has been linked to an increased risk of various health issues, including stress, anxiety, insomnia, and cardiovascular disorders. However, research on the relationship between residential traffic noise and mental health in South Korea is limited. Objectives: This study aims to examine the correlation between regional traffic noise levels and mental health using an ecological study design. Methods: In this ecological study, all data were collected from the Korean Statistical Information Service. Traffic noise data in residential areas and the prevalence of mental health indices in 44 cities with noise monitoring stations were obtained. Pearson correlation coefficients were calculated to assess the relationship between regional traffic noise levels and mental health indices. Results: Daytime traffic noise levels were found to have a positive correlation with stress perception (r=0.428, p=0.004) and showed a borderline positive correlation with depressive symptom prevalence (r=0.273, p=0.073). In cities with airports, significant correlations was observed between 24-hour average noise levels and depressive symptoms (r=0.604, p=0.010), whereas this relationship was not observed in cities without airports (r=0.048, p=0.813). Multiple regression analysis, which adjusted for factors such as age, gender ratio, smoking, obesity, unemployment, urban size, and the presence of an airport, confirmed the relationship between 24-hour average noise levels and stress perception (beta=0.287, p=0.024). Conclusions: This study identified correlations between regional traffic noise levels and depressive symptoms or stress perception in adults, with a more pronounced effect in areas with airports. These findings suggest a potential impact of residential traffic noise on mental health, highlighting the importance of preventive measures like noise management in urban planning to promote mental well-being.

• The Journal of Korean Medicine
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• 제27권4호
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• pp.125-134
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• 2006

During the prenatal period, the development of the individual is influenced by a host of environmental factors. Exposure to noise stress during pregnancy was determined to result in the retardation of growth, a reduction in neurogenesis, and an impairment of spatial learning ability in the rat pups. In the present study, we have attempted to characterize the effects of prenatal treatment with Cnidium officinale Makino on spatial memory and neurogenesis in the hippocampus of rat pups born from maternal rats exposed to noise stress during pregnancy. Prenatal treatment with Cnidium officinale Makino was shown to increase neurogenesis and enhanced spatial learning ability in rat pups born from maternal rats exposed to noise stress. In this study, we have determined that prenatal treatment with Cnidium officinale Makino can stimulate spatial development and neurogenesis in the brain of the fetuses exposed to prenatal stresses.

• Journal of Korean Society of Industrial and Systems Engineering
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• 제24권65호
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• pp.65-73
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• 2001

In this study, psychophysiological stress was quantitatively evaluated at various car interior noise levels by using Electroencephalogram(EEG). An experiment was performed to investigate the most comfortable range of noise level during simulated driving condition. Twelve healthy volunteers participated in the experiment. They were asked to operate the driving simulator while six levels of interior noise were given, such as 45dB(A), 50dB(A), 55dB(A), 60dB(A), 70dB(A), 80dB(A), and maximal subjective noise level. EEG signals were recorded for 60 seconds in each noise level. The power spectral analysis was performed to analyze EEG signal. At the same time, psychological stress was also measured subjectively by using a magnitude estimation method. The results showed that subjective stress and EEG spectrum indicated a statistically significant difference between noise levels. In particular, high level noise produced an increase in beta power at temporal(T3, T4) areas. It was also found that beta activity was highly correlated with subjective perception of discomfort, and subjects responded to car interior noise as arousing or negative stimuli. Moreover, beta power remained stable above 70dB(A), whereas subjective discomfort continued to increase even above 70dB(A) We concluded that brain waves could provide psychophysiological information of drivers emotional reaction to car interior noise. Thus, EEG parameters could be a new measure to determine optimal noise level in ergonomic workplace design after further verification in various experimental conditions.