• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.521-526
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• 2003

In this study the traffic noises were investigated for the subjective allowing limitation ion and the testified classes, 7 point scale was selected to evaluate the annoyance level with vocabularies. As a result, 'relatively annoying' is the most suitable expression for the allowing 1imitation, and the sound pressure levels for the traffic was 44.4㏈.

• Journal of the Korea Convergence Society
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• v.12 no.11
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• pp.359-369
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• 2021

In this study, a complex sample logistic regression analysis was performed to identify the factors affecting the activity restriction of 2,701 normal elderly and chronically ill elderly aged 65 and over using raw data from the 8th period of the National Health and Nutrition Examination Survey. It was found that the elderly with chronic disease felt more restricted in their activities than the normal elderly. Activity limiting factors in stroke and hypertension patients are subjective health status, economic level, stress perception, and moderate-intensity work and leisure. The factors limiting activity in patients with heart disease were subjective health status and economic level, and factors limiting activity in patients with joint disease were subjective health status and high-intensity work and leisure. Activity limiting factors for lung disease patients are education level, high intensity work and leisure, and endocrine system activity limiting factors include subjective health status, stress perception, high intensity work and leisure, and activity limiting factors for cancer patients. is subjective health status, stress perception, moderate-intensity work and high-intensity leisure. Rehabilitation programs and policy support are needed for the continuous participation of the elderly with chronic diseases.

• Science of Emotion and Sensibility
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• v.2 no.2
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• pp.37-42
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• 1999

Long-term exposure to loud noise affects performance since it changes arousal level, distracts attention, and also is able to evoke subjective stress accompanied by negative emotional states. The purpose of the study was to analyze dynamics of subjective and physiological variables during a relatively long-lasting (30 min) exposure to white noise (85 dB[A]). Physiological signals were recorded on 15 college students during 30 min of intense auditory stimulation. Autonomic variables, namely skin conductance level , non-specific SCR number, inter-best intervals in ECG, heart rate variability index (HF/LF ratio of HRV), skin temperature, as well as respiration rate were analyzed on 5 min epoch basis. Psychological assessment (subjective rating of stress level) was also repeated every 5 min. Statistical analysis was employed to trace the time course of the dynamics of subjective and autonomic physiological variables and their relationships. Results showed that the intense noise evoked subjective stress as well as associated autonomic nervous system responses. However it was shown that physiological variables endured specific changes in the process of exposure to the loud white noise. Discussed were probable psychophysiological mechanisms mediating reactivity to long-term auditory stimulation of high intensity, namely short-term activation, followed by transient adaptation (with relatively stable autonomic balance) and then a subsequent wave of arousal due to tonic sympathetic dominance.

• Korean Journal of Culture and Social Issue
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• v.11 no.2
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• pp.31-46
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• 2005

The purpose of the present study was to investigate the effects of in-vehicle noise types and levels of intensity on drivers' driving speed estimation. Noise generated from the vehicle engine and musical sound sampled from the Korean pop were employed as the types of in-vehicle noise and their levels of intensity were systematically manipulated. In experiment 1 where the effect of the engine noise levels on speed estimation was observed, drivers showed the tendencies of driving faster than the targets speeds under lower noise intensity condition whereas driving slower under higher noise intensity condition. In experiment 2 where both musical sample and the engine noise were provided, drivers' subjective speed estimation was affected by the engine noise as revealed experiment 1, but not by musical sample. When the data from the both experiments were combined and analyzed, an interacting effect of engine noise levels and music sample levels was found: if the intensity of music sample was enough to overwhelm the engine noise, the drivers drove faster than lower engine noise level condition in the experiment 1. This result indicates that although the music sample is not the direct auditory cue of speed estimation as observed in the experiment 2, intense level of music sample can affect drivers' speed estimation when it is coupled with the lower engine noise level.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1999.11a
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• pp.211-215
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• 1999

It is well known that a long-term exposure to a loud noise environment affects performance, since it distracts attention, and also is able to evoke stress accompanied by negative emotional states. The purpose of this study was to analyze dynamics of subjective and physiological variables during long-lasting (30 min) exposure to intensive white noise (85 dB[A]). Physiological signals on 23 college students were recorded by BIOPAC, Grass Neurodata systems and AcqKnowledge 3.5 software. Autonomic variables, namely skin conductance level (SCL), non-specific SCR number (N-SCR), inter-beat intervals in ECG (RR intervals), heart rate variability index (HF/LF ratio of HRV), respiration rate (RESP), and skin temperature (SKT) were analyzed on 5 min epoch basis. Psychological assessment (subjective rating of stress level) was also repeated on every 5 min basis. Regression and correlation analyses were employed to trace the time course of the dynamics of the subjective and autonomic physiological variables and their relationship. Results showed that intense noise evokes subjective stress with associated autonomic nervous system responses. However, it was shown that physiological variables endure specific changes in the process of exposure to loud white noise. Discussed are probable psychophysiological mechanisms mediating reactivity to long-term auditory stimulation of high intensity.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1999.11a
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• pp.216-221
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• 1999

A mental task combined with noise background is an effective model of laboratory stress for study of psychophysiology of the autonomic nervous system (ANS). The intensity of the background noise significantly affects both a subjective evaluation of experienced stress level during test and the physiological responses associated with mental load in noisy environments. Providing tests of similar difficulties we manipulated the background noise intensity as a main factor influencing a psychophysiological outcome and the analyzed reactivity along withe the noise intensity dimension. The goal of this study was to identify the patterns of ANS responses and the relevant subjective stress scores during performance of word recognition tasks on the background of white noise (WN) of the different intensities (55, 70 and 85 dB). Subjects were 27 college students (19-24 years old). BIOPAC, Grass Neurodata System and AcqKnowlwdge 3.5 software were used to record ECG, PPG, SCL, skin temperature, and respiration. Experimental manipulations were effective in producing subjective and physiological responses usually associated with stress. The results suggested that the following potential autonomic mechanisms might be involved in the mediation of the observed physiological responses: A sympathetic activation with parasympathetic withdrawal during mild 55 and 70dB noise (featured by similar profiles) and simultaneous activation of sympathetic and parasympathetic systems during intense 85dB WN. The parasympathetic activation in this case might be a compensatory effect directed to prevent sympathetic domination and to maintain optimal arousal state for the successful performance on mental stress task. It should be mentioned that obtained results partially support Gellhorn's (1960; 1970) "tuning phenomenon" as a possible mechanism underlying stress response.

• Journal of Oral Medicine and Pain
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• v.41 no.3
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• pp.99-109
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• 2016

Purpose: This study investigated factors influencing the xerostomia symptoms in the patients with temporomandibular disorders (TMDs). Methods: Eighty-six participants over the age of twenty were randomly enrolled from patients with TMDs. The patients were diagnosed by Diagnostic Criteria-TMD (DC-TMD). Intensity of the pain and level of stress of the patients were recorded using TMD pain visual analogue scale (VAS) and stress VAS, respectively. The Symptom Checklist-90-Revised (SCL-90R), dry mouth symptom questionnaire, unstimulated salivary flow rate (USFR) and oral moisture were measured. Results: The patients who had above the mean of the TMD pain VAS had significantly higher scores on the stress VAS, subjective dry mouth symptoms and T-score of somatization. The patients who suffered from pain more than three months had significantly higher TMD pain VAS, subjective dry mouth symptoms and T-score of somatization. There were no significant differences in xerostomic symptoms according to the diagnosis of TMDs. Moreover, TMD pain VAS and the stress VAS did not correlated to USFR and oral moisture. Conclusions: The level of individuals' TMD pain and stress significantly affect their subjective dry mouth symptoms, however, it did not affect USFR and oral moisture.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.05a
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• pp.225-230
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• 2001

Intensity of background noise is a factor significantly affecting both subjective evaluation of experienced stress level and associated electroencephalographic (EEG) responses during mental load in noisy environments. In the study on 27 subjects we analyzed the influence of the background white noise (WN) intensity on psychophysiological responses during a word recognition test. Electrocortical activity were recorded during baseline resting state and 40 s long performance on 3 similar Korean word recognition tests with different intensities of background WN (55, 70 and 85 dB).. An important finding in terms of physiological reactivity was similarity of all physiological response profiles between 55 and 70dB WN, i.e., none of physiological variables differentiated the two conditions, while 85dB WN resulted in a significantly different profile of reactions (higher fast beta power in EEG spectra). This condition was characterized by highest subjective rating of experienced stress, had more fast beta activity and had tendency of right hemisphere dominance, emphasizing the role of brain lateralization in negative affect control.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.917-917
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• 2003

The auditory experiments based on the subjective annoyance responses were undertaken for the establishment of the adverb modifiers of the heavy-weight impact noises. The standard heavy weight impact noise, impact ball noise and adult walking noise were recorded by dummy head at a newly-built apartment and were presented to the subjects by headphones. The levels of the three impact noises were varied from 30 to 60㏈(A) and the subjects matched one of the adverb modifiers to each level of the noise sources. As a result, seven scale modifiers were established and the intervals between the modifiers were found as equal. In addition, it was found that the lower annoyance noise limits for the heavyweight impact, impact ball and walking were 40-45㏈ (L$\sub$I, Fmax. AW), which is 6㏈ lower than in the previous study. The background noise level was as low as 21㏈(A) in the test booth, therefore, the testing conditions need to be concerned for evaluation of floor impact noise.

• Journal of Multimedia Information System
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• v.4 no.2
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• pp.89-92
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• 2017

This paper investigates simple gray level image enhancement technique based on Genetic Algorithms and Local Statistics. The task of GA is to adapt the parameters of local sliding masks over pixels, finding out the best parameters preserving the brightness and possibly preventing the creation of intensity artifacts in the local area of images. The algorithm is controlled by GA as to enhance the contrast and details in the images automatically according to an object fitness criterion. Results obtained in terms of subjective and objective evaluations, show the plausibility of the method suggested here.