• Journal of Korean Ophthalmic Optics Society
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• v.17 no.3
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• pp.285-291
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• 2012

Purpose: This study was conducted to research any effect on visual function related to accommodation by VDT work. Methods: The refraction power, accommodative lag, accommodative facility, relative accommodation, amplitude of accommodation and blink rate were measured before and after VDT work for 2 hours on 48 university students (16 males and 32 females), without abnormal accommodative function and systemic and ocular disease, who had never undergone corrective eye surgery. All examinations were performed with distant refraction, and a survey was conducted on the items related to subjective symptoms of VDT syndrome. Results: After 2 hours of VDT work, refractive power increased by 0.23 D, the amount of change in accommodative lag were $0.17{\pm}0.42D$ in the right eye and $0.23{\pm}0.47D$ in the left eye (t=2.26, p=0.03). There were statistically significant differences. Both the accommodative facility and relative accommodation and amplitude of accommodation were decreased after work. However, blink rate were increased. After VDT work, 33.4% of the subjects showed subjective symptoms of asthenopia and 33.3% of them showed shoulder pain. Conclusions: As a result, the accommodative lag increased in response to the two hours of VDT work, and overall accommodative functions were decreased. In addition, as symptoms of providing visual strain, asthenopia showed the most prominent subjective symptoms.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.3
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• pp.156-161
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• 2012

Purpose: This study was conducted to obtain difference in fracture strength according to the diameter of one-body O-ring-type of mini implant fixture, to determine the resistance of mini implant to masticatory pressure, and to examine whether overdenture using O-ring type mini implant is clinically usable to maxillary and mandibular edentulous patients. Materials and methods: For this study, 13 mm long one body O-ring-type mini implants of different diameters (2.0 mm, 2.5 mm and 3.0 mm) (Dentis, Daegu, Korea) were prepared, 5 for each diameter. The sample was placed at $30^{\circ}$ from the horizontal surface on the universal testing machine, and off-axis loading was applied until permanent deformation occurred and the load was taken as maximum compressive strength. The mean value of the 5 samples was calculated, and the compressive strength of implant fixture was compared according to diameter. In addition, we prepared 3 samples for each diameter, and applied loading equal to 80%, 60% and 40% of the compressive strength until fracture occurred. Then, we measured the cycle number on fracture and analyzed fatigue fracture for each diameter. Additionally, we measured the cycle number on fracture that occurred when a load of 43 N, which is the average masticatory force of complete denture, was applied. The difference on compressive strength between each group was tested statistically using one-way ANOVA test. Results: Compressive strength according to the diameter of mini implant was $101.5{\pm}14.6N$, $149{\pm}6.1N$ and $276.0{\pm}13.4N$, respectively, for diameters 2.0 mm, 2.5 mm and 3.0 mm. In the results of fatigue fracture test at 43 N, fracture did not occur until $2{\times}10^6$ cycles at diameter 2.0 mm, and until $5{\times}10^6$ cycles at 2.5 mm and 3.0 mm. Conclusion: Compressive strength increased significantly with increasing diameter of mini implant. In the results of fatigue fracture test conducted under the average masticatory force of complete denture, fracture did not occur at any of the three diameters. All of the three diameters are usable for supporting overdenture in maxillary and mandibular edentulous patients, but considering that the highest masticatory force of complete denture is 157 N, caution should be used in case diameter 2.0 mm or 2.5 mm is used.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1409-1416
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• 2012

This study examined the effects of four herbal sports drinks containing Prunus mume, Liriope platyphylla, and Acanthopanax senticosus fruit extracts on body fat and endurance of rats trained by a progressive loaded exercise program. Forty male Sprague-Dawley rats (6 weeks old) were divided into five groups and fed experimental diets for 6 weeks according to the following protocol: C, exercise-trained control group (n=8); A, exercise group with Acanthopanax senticosus extract (n=8); L, exercise group with Liriope platyphylla extract (n=8); PA, exercise group with Prunus mune fruit extract plus Acanthopanax senticosus extract (n=8); PL, exercise group with Prunus mune fruit extract plus Liriope platyphylla extract (n=8). Endurance was measured by a progressive loaded exercise test using a treadmill. PA and PL supplementation significantly extended time to exhaustion compared to the control group (p<0.05). Further, the four herbal sports drinks all significantly reduced epididymal and interscapular white adipose tissue weights compared to the control group (p<0.05). Plasma triglyceride concentration was significantly lower in the A group compared to the control group. Plasma free fatty acid concentration was higher in the A group compared to the control group. On the other hand, Acanthopanax senticosus fruit extract supplementation tended to reduce the plasma glucose concentration compared to the control group. PA and PL supplementation significantly increased gastrocnemius muscle LDH activities compared to the control group (p<0.05). These results show that sports drink containing Acanthopanax senticosus improved endurance capacity, plasma lipids, and glucose concentrations. Sports drink with Prunus mume and Liriope platyphylla or Acanthopanax senticosus was synergistically improved endurance.

• Journal of Convergence for Information Technology
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• v.7 no.5
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• pp.47-51
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• 2017

The purpose of this study was to investigate the effect of wearable sensor wear on the muscle contraction of cervical erector spinae and upper trapezius causing the forward head posture induction in order to reduce the stress induced by the use of smartphone. This study was to investigate the muscle activity of healthy adults in the 20th to 30th generations by dividing them into the control group using the smartphone, the non-wearing group conscious the posture of the head posture, and the wearing group wearing the wearable sensor. There were no differences in muscle activity between cervical erector spinae and upper trapezius compared to the control, non - wearing, and wearing groups. In addition, the changes in muscle activity of cervical erector spinae muscles were increased in all groups, but the muscle activity of upper trapezius muscles were in the wear group compared to the non-wear group and the control group, but there was no statistical significance. That is, wear of the wearable sensor may be effective in controlling the conscious posture, but it may cause the compensation of another part.

• Journal of Korea Society of Industrial Information Systems
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• v.5 no.2
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• pp.1-8
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• 2000

Manual material handling(MMH)is major factor which causing physical injuries of worker at working area and frequency of low back pain(LBP) is increasing industrial accidents. Especially, working in bad circumstance such as farm, orchard, harbor loading and unloading, logging place and mining place which located in inclined slope can cause much possibility of hazard and absence of working balance can cause injuries of musculoskeletal system such as joint, bone, ligament. So, this study used EMG system to measure and evaluate muscle force information and fatigue of worker when lifting on slope. The result of measuring averaged integrated EMG(AEMG) shows multifidus muscle be used more than anything else in force. neck extensors are used at 15°, 20°frequently. generally the AEMG result shows multifidus muscle be used in force. Commonly, muscle fatigue of multifidus is higher than other muscle by analysis mean power frequency(MPF). The result of load sharing rate shows multifidus and erectorspinae which are deep spinal muscles is relatively high and neck extensor is low.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.970-977
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• 1995

Effect of garlic intake on the antifatigue and fatigue recovery during prolonged exercise have been investigated. 16 male college students(8 persons of control group and the same numbers of garlic intake group), aged from 20 to 22 years, were subjected to the restricted experiment and maintained their same menu with exercise in life pattern during 14 days of program. In garlic intake group, 30g of garlic was given with every 3 meal per day to each person. A significant increase in HDL-cholesterol level was shown in the garlic intake group while total cholesterol, LDL-cholesterol and lactate level decreased by garlic intake. Lactate dehydrogenase activity in serum increased by garlic intake, however garlic intake was not significantly affected on Vo2, Vco2, ventilation, respiratory quotient. In conclusion, garlic intake seemed to be effective for antifatigue and tatigue recovery during prolonged exercise.

• Journal of Digital Convergence
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• v.19 no.12
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• pp.457-462
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• 2021

As South Korea is a mountainous topography, installation of tunnel is essential for construction of expressway in straight lines. According to "2019 Road Bridge and Tunnel Status Report", there are 2,682 tunnels in Korea with total length of 2,077km. Tunnels take up 1.9% of total road length and the number of tunnel increased by 94% with 1,300 newly constructed tunnels over the 10 years. According to domestic and foreign researches, a long tunnel over 1km in expressway has dark lightings and monotonous wall design which decrease driver's concentration and make the driver feel bored. This leads to feeling fatigue and drowsiness more easily. In response, Korea Expressway Corporation installed design lighting that increases attentiveness on 10 tunnels with total length over 3km by 2020. To reduce the risks of accident that may happen inside the tunnel, this study conducted a comparative analysis on characteristics of each type of LED landscape lighting installed inside the expressway tunnel. The study aimed on providing the basic material for effective installation of LED landscape lighting for securing driving stability, reducing fatigue, and lowering the risk of drowsiness.

• Journal of Broadcast Engineering
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• v.17 no.1
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• pp.60-72
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• 2012

After the movie "AVATAR" became a good model of cash-cow in 3D movie, the profit of 3D-movie significantly reduced. One of the reasons why it happens comes from rare understanding of human factors for instance how viewers get immersed, but sometimes tired. Although 3D images should be more considered human visual system including eye, unfortunately most communication research ignored human factors. For those reasons this study observed the effect of 3D video on viewers' psychological response, especially for perceived eye movement, perceived characteristics, visual fatigue, and presence. With 90 participants, the results show that viewers' perceived feature effects on their presence. In detail, first, materiality and tangibility are more important factors than clarity in 3D video, and it means that when making 3D content or devices, materiality and tangibility should be considers that any other factor. Second, this study examined whether we perceive our eyes as media, and the result shows that as viewers' presence level became higher we perceive eye movements more, and as viewers' presence level became higher perceived visual fatigue became lower. This result means that when we move eyes, we interact with surrounded environment, so 3D content needs to provide vivid features to be more interactive. On the other hand, since level of presence increase visual fatigue, it must be balanced when producing and playing.

• Journal of Korean Medicine for Obesity Research
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• v.15 no.2
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• pp.153-161
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• 2015

Gamrosu is a modified fasting therapy beverage (431 kcal/d). A retrospective observational study was conducted to investigate the detoxification feasibility of Gamrosu. Three cases were reviewed which participants have finished the fasting with Garmrosu for 10 consecutive days. Detoxification profiles of Gamrosu were reviewed at pre- and post-fasting sessions. Post-Gamrosu session, -6.3% of average weight, -6.5% of average body fat mass and -6.6% of average muscle mass were reduced with the nutrition indices being improved. The inflammation indices showed the significant diminished profiles. Liver/kidney functions and the standard of electrolytes were maintained within normal range in stable manners, however, marginal elevation of total bilirubin and mild ketoacidosis were observed. The indices of oxidative stress decreased and those of antioxidative activity increased. The fatigue scale scores indicated lower scores except insomnia symptom. Taken together, detoxification profiles of Gamrosu were sufficiently feasible and the observed findings should be considered for further clinical studies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.840-849
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• 2005

In order to investigate the relationship between intake conditions of health food and health-related factors by residence and sex in Tong-Young area, a survey was carried out from 1,303 adults. Health foods were classified 3 groups including vitamin and mineral supplements, toner foods and manufactured health food supplements. Health-related factors were stress, fatigue, smoking and drinking. The $29.5\%$ of the subjects had taken some health food for health. Especially the male took more toner foods habitually than the female did. In take of vitamin and mineral supplements by residence, there was a significant difference $(p\leq0.01)$ as follows. The subjects in island $(20.0\%)$ who took vitamin/mineral supplements were about two times as compared with the subjects in Dong $(10.8\%)$, or Eub-Myeon $(10.0\%)$. The subjects taking supplementary food replied over fair $(82.8\%)$, the subjects taking toner food replied over fair (90.3$\%$) scored higher than who replied bad or very bad in self-perceived health status. Therefore, the better the subjects felt self-perceived health status, the more they took health foods for health themselves. In self-perceived stress status, the subjects who replied a little $(50.0\%,\;45.3\%)$ or little $(19.9\%,\;26.4\%)$, took vitamin and mineral supplements or manufactured health foods a lot. In toner food there was a significant correlation $(p\leq0.05)$ as follows. The less the subjects felt stress, the more they took dietry supplement. No smoker $(12.9\%)$intake rate of vitamin and mineral supplements was higher than smoker $(8.8\%)$. Smokers $(6.5\%)$ intake rate of toner food was higher than no smoker $(4.0\%)$. It was not significant the relationship between intake condition of health food and drinking. The main motivation for taking health food were by self-decision and invitation of friends or neighbors.