• Journal of the korean academy of Pediatric Dentistry
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• v.50 no.3
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• pp.239-251
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• 2023

The aim of this study is to evaluate the effect of noise-filtering earplugs on the hearing ability of dentists wearing them during noise-induced dental procedures. Pure tone audiometry and distortion product otoacoustic emission (DPOAE) tests were conducted at the initial visit and 1 year later to evaluate the hearing ability of the participants. As a result of the study, the pure tone average of the group wearing earplugs decreased significantly compared to the group not wearing earplugs, indicating an improvement in hearing. However, the signal-to-noise ratio of the DPOAE tests did not show a significant difference. These findings suggest that noise-filtering earplugs may have some effectiveness in preventing hearing loss. However, since the 1-year observation period may not be adequate to identify changes in hearing, a follow-up study with an extended follow-up period is necessary.

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.2
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• pp.91-98
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• 2016

Purpose: This study investigated the masking effect of the hydrogel lens and silicone hydrogel lens on the cornea with refractive surgery and without surgery. Methods: 24 university students (means age: $23.48{\pm}2.89years$) without refractive surgery (12, control group) and with refractive surgery (LASIK: 8, LASEK: 4, experimental group) participated in the study. Mean refractive errors of right eyes were -2.73 D for control group and -0.24 D for experimental group. The differences in the refractive power and corneal topography map between pre- and post-wearing the -3.00 D lenses were compared, and 2 kinds of hydrogel contact lenses (0.89 Mpa, 0.49 Mpa) and 2 kinds of silicone hydrogel lenses (1.5 Mpa, 0.8 Mpa) were used for -3.00 D lenses. NVision-K5001 (Shin nippon, Japan) was used to measure the refractive power and Keratograph 5M (Oculus, Germany) to measure the corneal topography map change. Results: Variations in the refractive power increased to the plus direction in the experimental group after wearing soft contact lenses. The corneal topography map showed significant changes on the both groups after wearing soft contact lenses (p<0.05). However there were no significant differences in the refractive power and corneal topography map variations by lens materials. Conclusions: Wearing soft contact lenses showed corneal topography map changes. Especially wearing soft contact lenses on the flat cornea after corneal refractive surgery showed greater corneal power changes. Therefore, it should pay attention to refractive change in case of prescribing soft contact lenses to patients with corneal refractive surgery.

• Fashion & Textile Research Journal
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• v.15 no.4
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• pp.504-513
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• 2013

This study evaluates the difference of visual effect according to pant style and geometric pattern. The researcher made 28 stimuli-combination of four pant Stiles (classic, baggy, skinny, and bell-bottom) and seven geometric pattern (large vertical stripe, small vertical stripe, large horizontal stripe, small horizontal stripe, large check, small check, and hound's tooth check). The test involved 96 female college students. The stimuli were made with the i-Designer computer program. The panels tested the computer screen images of all manikins wearing pants. A 7-point scale was used to evaluate each image. For the data analysis, ANOVA and Duncan-test were applied along with an SPSS program. The results of this study are as follows. Three factors (lower-body compensation, abdomen highlight, and length compensation) influenced the visual effect pant styles and geometric patterns. The skinny style and large vertical stripe evaluated positively in elongated height and leg length and a slimmer overall body. It was shown that the vertical stripe pattern was evaluated as more positive than the horizontal stripe pattern in the visual effect; particularly, the results showed distinct aspects in the classic pants style. The mutual influence of the visual effect (according to pants style and geometric pattern) were indicated as two factors of lower-body compensation and length compensation. A more positive visual effects resulted in a higher mutual influence on pant style and geometric pattern.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.1
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• pp.5-11
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• 2006

This study was performed to determine the effect of structural characteristics of selected wool fabrics on mechanical and thermal properties. 52 wool fabrics, including 18 plain woven fabrics and 34 twill and satin woven fabrics were used as samples woven with various weft density for the study. Several physical characteristics such as mechanical properties, keeping warmth ratio of wool fabrics were measured. Data analyses including 1) analysis of tactile and thermal comfort sensation were performed. the following were obtained from the results: The main factors affecting keeping warmth ratio were thickness and bulk density. The keeping warmth ratio of samples increased with increasing thickness and decreasing bulk density of samples. In addition, coefficient of friction of the samples increased with keeping warmth ratio of samples. The above results show that wearing sensation and comfort properties of fabrics are changed depending on the end-use, and thus, above results can be used to manufacture of fabrics for specific end-use with high comfort properties.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.1
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• pp.43-49
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• 2008

This study is about an influence of harmful factors of welding fumes such as Fe, Mn, Cu, Zn to workers who inhales them in welding sites. The influence can be measured with the density of heavy metals in blood after welding. The main factors of the measurement are TWA, a density of welding fume, and a level of heavy metals. The results indicate that there is a positive effect of moving fans as a way of improving the condition in welding workplaces. While welding was done, TWA exceeded the level of Fe 40% and Zn 10% and the level of heavy metals in blood was below the standard for the workers who were under the experiment. Also when the wind was applied on the front side by a fan, the welding fume significantly reduced. It can be concluded that wearing protection gears with safety devices is one of important factors.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.4
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• pp.562-569
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• 1997

The axial position of an impeller is misaligned in the process of manufacturing and assembling. For a single suction centrifugal pump with balancing holes, the effect of axial displacement of impeller on the performance, leakage loss and axial thrust acting on the impeller is experimentally investigated. The axial displacement decreases the pump efficiency, increases the leakage through the clearance between wearing ring and impeller, and affects the characteristics of axial thrust.

• Proceedings of the KWS Conference
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• 2007.11a
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• pp.306-309
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• 2007

It shows not only positive effect with fan as a way of improving condition in workplace but also shows air supply, ventilation condition in welding site with CFD analyzation. Also when the wind blew to the front side by a fan, the welding Hume significantly reduced, As this was examined as CFD and was gone through enough exhaustion to become streamline flow laminar, the toxic materials will be reduced. The improvement of welding work and education are investigated to be more significant factors than wearing protective equipments and setting safety tools to prevent welding works from welding fume exposure.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.24-26
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• 2019

Air Pollution is increasing in Korea due to recent factory and environmental pollution and desertification in China. People are said to be wearing masks or reducing outdoor activities, but there is little effect on quarantine. Therefore, in order to clean up Air Pollution that has an adverse effect on the body, the government is planning to design a Prototype, an Air Pollution measuring system based on the Internet of Things.

• Journal of Fashion Business
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• v.16 no.6
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• pp.144-159
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• 2012

This study was to examine the effect of standards of selecting jeans and appearance management behavior on leisure lifestyle. Questionnaires were administered to 253 college students living in Deagu and Kyoungbuk. Data were analyzed by using frequency, factor analysis, regression analysis, t-test, and ${\chi}^2$-test. The findings are as follows. Factor structure of each concept appeared to be brand-valued, functionality valued and design-valued for standards of selecting jeans, diet management, exercise management, weight management and appearance satisfaction. Leisure lifestyle consisted of sports activity-type, sociality-type and self-management-type while value lifestyle consisted of active sociality-oriented, family-oriented and economic feasibility-oriented. There was a significant difference in brand-valued and design-valued of standards of selecting jeans and in frequency of wearing jeans male students showed higher than female students. The result of this study showed brand-valued, diet management, exercise management, weight management, and appearance satisfaction had significant effect on sports activity-type and design-valued and weight management had significant effect on sociality-type. Brand-valued affected self-management-type significantly and brand-valued, design-valued, diet management and appearance satisfaction had a significant effect on active sociality-oriented and brand-valued and diet management affected family-oriented.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.4
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• pp.551-562
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• 1999

This study was intended to investigate the effect on the human body such as subcutaneous fat thickness the circumference of extremities etc. of the clothing training of putting on thin clothes periodically from the cold period. The subjects were divided into the clothing training group and the non-training group, The training group was asked to wear cool clothes in daily life and to wear the training clothes of T-shirts with half-length sleeves and pants and perform the clothing training for two hours daily three times a week in a cold environment over the period from November to February. The non-training group was asked to lead a life wearing comfortable clothes. Then a comparative experiment was conducted at 15$\pm$1$^{\circ}C$, 50$\pm$5% R, H and 0.25m/sec before and after the clothing training. After the clothing training regardless of gender subcutaneous fat thickness was more increased and total clothing weight per the surface area of the body was decreased in the training group than the non-training group. The training group showed lower skin temperature in the limbs and lower average skin temperature than the non-training group irrespective of gender which proved the effect of the clothing training. The training group was shown to have attendancy toward a greater sense of warmth and a less sense of discomfort which proved the effect of the clothing training.