• IE interfaces
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• v.17 no.2
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• pp.218-225
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• 2004

This study aims to investigate effect of external load and motion repetitiveness on perceived discomfort. An experiment was performed for measuring discomfort scores at varying conditions, in which external load, motion repetitiveness and arm posture were employed as experimental variables. The arm posture was controlled by shoulder flexion and abduction, and by elbow flexion. Fifteen healthy college-age students without history of musculoskeletal disorders voluntarily participated in the experiment. The results showed that the effect of external load, motion repetitiveness and shoulder posture on discomfort were statistically significant, but that elbow posture did not significantly affect discomfort ratings. The effect of external load was much larger than that of any other variables, and that of repetitiveness was second only to external load. Discomfort scores significantly increased linearly as the levels of external load and motion repetitiveness increased. This implies that although they were not fully reflected in the existing posture classification scheme such as OWAS, RULA, etc., the effect of external load and motion repetitiveness should be taken into consideration for precisely quantifying work load in industry. Based on regression analysis, equivalent values of external load and motion repetitiveness in terms of discomfort scores were provided, which would be useful for better understanding the degree of their effect on work load.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.10
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• pp.16-26
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• 2012

This study conducted a subjective evaluation of brightness perception and visual discomfort according to dimming speeds and CCTs(Correlated Color Temperatures). Dimming speeds of two different CCT lights(2,700K, 6400K) were set to 1.7%/s, 3.3%/s, 5.0%/s, 6.7%/s, and 10.0%/s respectively. Subjects checked the time when they perceived the change of the brightness and visual discomfort. As a result, when dimming speeds were 1.7%/s, 3.3%/s, 5.0%/s, 6.7%/s, more than half of subjects responded the change of the brightness in 55.0~45.0% dimming ratios, and felt the visual discomfort in 35~25% dimming ratios. When the brightness was changed, dimming level responded to the brightness perception of hight CCT(6,400K) was higher about 8.0% then dimming level responded to the brightness perception of low CCT(2,700K). Dimming level responded to the visual discomfort of low CCT(2,700K) was higher about 5.0% then dimming level responded to the visual discomfort of hight CCT(6,400K).

• Journal of dental hygiene science
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• v.18 no.5
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• pp.319-326
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• 2018

Although scaling is the primary method for improving oral health, it is also associated with dental fear. The objective of this study was to empirically verify whether the use of gel anesthetic within the gingival sulcus during scaling relieves pain and improves other factors. A total of 128 patients scheduled to undergo scaling at a dental clinic of a general hospital located in the Gyeonggi Province, between July 2014 and July 2015, were enrolled in the study. The participants underwent scaling following the application of 20% benzocaine gel or placebo gel anesthetic within the gingival sulcus, and the data was collected using a questionnaire. There was a significant difference in the severity of pain, participant satisfaction, perceived sensitivity, overall discomfort, and fear of scaling between the two groups. The two groups were compared in terms of perceived need for gel anesthesia, willingness to pay for anesthesia costs, and willingness to receive scaling in the future. There were significant differences in all the three parameters depending on whether gel anesthesia was used or not. There were significant differences between the two groups in perceived sensitivity immediately after scaling and one day after scaling, with no difference seen one week after scaling. With regards to overall discomfort over time, there were significant differences between the two groups immediately after scaling. Based on these findings, we expect that application of gel anesthetic within the gingival sulcus during scaling will reduce pain, perceived sensitivity, overall discomfort, and fear of scaling with increased satisfaction.

• Journal of Korean society of Dental Hygiene
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• v.1 no.1
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• pp.53-62
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• 2001

The purpose of this study was to measure of dental impact on daily lining among workers. The number of subjects were 1.457 workes. To predict the oral health of workers, we used the measurement of dental impact on daily living. Using methodology was self-questionnaire which included the perceived oral health status, and performance, appearance, pain, eating restriction and discomfort. The associations between the performance factors and perceived oral health status, pain, eating restriction and discomfort, the results were as follows: 1. There were consisted of 48.3% of female. 63.1% of smokers. 92.3% of lower than 30years and 99.4% of graduating high school. 2. Measurement of daily impact on daily living were classified into the following 6 categories. Facter analysis for validity was carried out for corroboration. 3. Association between performance factors and other factors(pain, eating restriction and discomfort) were evaluated by multiple regression was significant(44%, p<0.01).

• KIEAE Journal
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• v.7 no.4
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• pp.17-22
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• 2007

The existing discomfort glare models are based on research that was conducted exclusively with uniform luminance sources. It is impossible to apply the models to windows of non-uniform luminance. For evaluating discomfort glare from windows, the method selecting glare source on a window plane is necessary. This study was carried outto propose a practical method to choose glare source from anon-uniform window plane. In the experiment, the perception of glare source according to the luminance difference is examined using a simulated windowof non-uniform luminance. The surface of the window is divided into two or three parts, and different luminance is setting on each surface. The observers were asked to decide whether the lower part of the window can be perceived as a glare source or not. The result shows that the lower part is perceived as a glare source when the lower part has over 37% of the luminance of the upper part of the window divided into two parts, and when it has over 51% of the luminance of the upper part of the window divided into three parts. the results may be applicable to select the glare source in awindow.

• Safety and Health at Work
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• v.8 no.2
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• pp.212-219
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• 2017

Background: Low back pain (LBP) is a major problem for office workers. Individuals adopting poor postures during prolonged sitting have a considerably increased risk of experiencing LBP. This study aimed to investigate seat pressure distribution characteristics, i.e., average pressure, peak pressure ratio, frequency of postural shift, and body perceived discomfort (BPD), during 1 hour of sitting among office workers with and without chronic LBP. Methods: Forty-six participants (chronic LBP = 23, control = 23) typed a standardized text passage at a computer work station for an hour. A seat pressure mat device was used to collect the seat pressure distribution data. Body discomfort was assessed using the Body Perceived Discomfort scale. Results: Office workers with chronic LBP sat significantly more asymmetrically than their healthy counterparts. During 1-hour sitting, all workers appeared to assume slumped sitting postures after 20 minutes of sitting. Healthy workers had significantly more frequent postural shifts than chronic LBP workers during prolonged sitting. Conclusion: Different sitting characteristics between healthy and chronic LBP participants during 1 hour of sitting were found, including symmetry of sitting posture and frequency of postural shift. Further research should examine the roles of these sitting characteristics on the development of LBP.

• Journal of Korean Academy of Nursing Administration
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• v.22 no.4
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• pp.362-372
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• 2016

Purpose: The aim of this study was to investigate whether job satisfaction in clinical nurses was dependent on work intensity and whether physical discomfort mediated the relationships between these variables. Methods: Structural equation modeling was used with a sample of 253 clinical nurses from four general hospitals. In the model, absolute work intensity, relative work intensity, and flexibility were considered as exogenous variables and physical discomfort as a mediating variable. Data were collected using self-report measures such as the Labor Intensity Questionnaire, the Rating of Perceived Exertion, and the Index of Job Satisfaction. Results: The results of the structural equation modeling found that the higher scores on absolute and relative work intensity were positively associated with physical discomfort but only relative work intensity was significantly related to job satisfaction. Physical discomfort mediated the relationships between absolute work intensity and job satisfaction and between relative work intensity and job satisfaction. Among three kinds of work intensity, only relative work intensity had direct and indirect effects on job satisfaction. Conclusion: The findings suggest that increase in relative work intensity might play an important role in decreasing job satisfaction in clinical nurses and a reasonable reward system considering relative work intensity could be necessary.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.191-199
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• 2015

The purposes of this study are to examine the predictability of variables related to SNS intention to use in collaborative learning and provide some new implications. Based on Technology Readiness and Acceptance Model (TRAM), we hypothesized that optimism, innovativeness, discomfort, insecurity as personal disposition variables, subjective norm as a social variable, and perceived usefulness and perceived ease of use as cognitive variables would predict SNS intention to use. For this study, 274 'Share Leadership' students in E university completed surveys and it was analyzed by multiple regression analysis. The results of this study showed as follows. First, optimism, innovativeness, discomfort, and subjective norm predicted perceived ease of use. Second, optimism, insecurity, subjective norm and perceived ease of use predicted perceived usefulness. Third, subjective norm, perceived ease of use and perceived usefulness predicted SNS intention to use. From this, it is revealed that positive technology readiness predict much more than negative technology readiness do and the role of teacher and peers is very important.

• Journal of the Ergonomics Society of Korea
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• v.15 no.2
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• pp.51-62
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• 1996

This research utilized the psychophysical methodology, where secrw drivers are used, to determine the effects of i) the location and orientation of work objects, and ii) wearing gloves, on ratings of perceived exertion at various body parts. The validity of the psychophysical methodology in determining a preferred work pace was also studied. The subjects drove screws with a screw driver into thick wooden sheet at three vertical and three horizontal locations. They drove serews for 3 minutes at each location and assessed the condition using the psychophysical scale. The results showed that only the vertical location was a significant factor in determining the discomfort ratings. Driving screws at elbow height on the vertical surface and with the lower arm close to the body on the horizontal surface were the work locations with the smallest ratings of perceived discomfort. Wearing gloves had significant effects on reducing the pain of the hand. From the experiment in which a comfortable work pace was identified using 20 minute psychophysical adjustment, it was found that the psychophysical method is sensitive to workers perception of the physical stress when the upper limbs are employed. This was confirmend by the high correlation between the psychophysical results and EMG measurement.

• Proceedings of the ESK Conference
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• 2004.10a
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• pp.22-22
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• 2004