• The Journal of the Korean dental association
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• v.17 no.11 s.126
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• pp.849-853
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• 1979

The number of occlusal contact points and he occlusal relation were investigated in dental students who were selected on the basis of normal occlusion and normal function of stomatognathic system. Silicone-Black Bites obtained from fifty subjects were analyzed on their white models and occlusal contacts were traced on models directly. The results were as follows; 1. There was no evident difference in the number of occlusal contact points between right and left sides 2. In the retruded position the numbers of occlusal contact points were $5.96{\pm}3.35$ in the upper jaws and $6.12{\pm}3.52$ in the lower jaws. 3. In the retruded position no occlusal contact point was found on the central and lateral incisors of upper and lower jaws. 4. Occlusal contact points were found almost on second molars of upper and lower jaws in the retruded position.

• Physical Therapy Rehabilitation Science
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• v.11 no.4
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• pp.421-429
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• 2022

Objective: The purpose of this study was to compare and analyze the effects of arch support taping on static balance, static/dynamic foot contact area, and ground reaction force during walking according to the types of elastic tapes with mechanical elasticity differences. Design: Cross-sectional study Methods: Twenty-six participants selected for flexible flat feet through the navicular drop test were randomly assigned to non-taping, Dynamic-taping, and Mechano-taping conditions. Static balance and foot contact area were compared in the standing posture according to arch support taping conditions, and foot contact area and ground reaction force were compared during walking. Results: There was no significant difference in static balance according to the taping condition in the standing position, but the foot contact area in the Mechano-taping condition showed a significant decrease compared to the non-taping condition (p<0.05). The foot contact area during walking significantly decreased in the Dynamic-taping and Mechano-taping conditions (p<0.05), but there was no significant difference between the ground reaction force. Conclusions: Based on the results of this study, it was confirmed that among the types of elastic taping, arch support taping using dynamic taping and Mechano-taping has the effect of supporting the arch with high elastic recovery. Any type of elastic tape can be used for arch alignment in flexible flat foot.

• Journal of Life Science
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• v.9 no.5
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• pp.590-595
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• 1999

The objectives of this research were to estimate variation characteristics of TOC, UV-254 and NH4+-N, etc, if odorous generated algaes flowed into water treatment plant and they contacted with ozone known as typical advanced treatment. It was estimated that pH decreased from initial 7.4 to 2.1 after ozone contact 100min. pH declined to early 10min. suddenly and then pH drop did almost occur. TOC and UV-254 continued to decrease with passed time of ozone contact. NO3--N concentration was much higher than NH4+-N and NO2--N for whole test period. Because ozone oxidized organic matters as various kinds of ion material and ion intensity of sample was extended, conductivity showed high as passed time of ozone contact. Owing to ozone oxidation of algae, color did almost disappear after ozone contact 20min.

• Journal of Mechanical Science and Technology
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• v.17 no.3
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• pp.321-328
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• 2003

The elongation of contact length on the line of action is considered with particular reference for roll forming of gears, and for dynamic behavior of the tooth in meshing. However there is no paper that discuss the elongation of contact length in the load meshing of gears. Based on our investigation, the contact length on the line of action elongates more than the kinematically calculated value. In rolling, as the tool approaches the workpiece, the center distance of the gears decreases by a small amount. But, the elongation of contact length is sensitive. Therefore, the contact point on the line of action is difficult to be determined, which complicates the tooth analysis. In this study, the exact relation between the elongation of contact length and the tooth space over the recess or before the approach are revealed by experiments and kinematic theory. This analytical result applies not only for rolling, but also for the single flank meshing which is done under constant center distance.

• PNF and Movement
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• v.8 no.2
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• pp.9-15
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• 2010

Purpose : This study aimed to investigate the effect of differing ground contact conditions on the eletromyographic(EMG) activity in rectus femoris, biceps femoris, tibialis anterior, gastrocnemius medialis during step-up activity in patients with hemiparesis. Methods : 10 hemiparetic patients performed step-up activity on three different ground contact conditions: entire ground contact, 2/3 ground contact, 1/3 groud contact. Result : The EMG activities of gastrocnemius medialis significantly changed on 1/3 ground contact(p<.05). However, no significant changed rectus femoris, biceps femoris, tibialis anterior between three differing ground contact conditions (p>.05). Conclusion : This study provides that EMG activities of gastrocnemius medialis significantly changed on different ground contacts. Therefore, this method can be used to strengthen the gastrocnemius medialis.

• International Journal of Control, Automation, and Systems
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• v.5 no.5
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• pp.601-605
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• 2007

In this paper, we propose a simple and relative electrode contact monitoring method. By exploiting the power line interference, which is regarded as one of the worst noise sources for bio-potential measurement, the relative difference in electrode impedance can be measured without a current or voltage source. Substantial benefits, including no extra circuit components, no degradation of the body potential driving circuit, and no electrical safety problem, can be achieved using this method. Furthermore, this method can be applied to multi-channel isolated bio-potential measurement systems and home health care devices under a steady measuring environment.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.837-842
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• 1994

The boundary element method was used for studying singularities of an interface crack with contact zones. Because the contact zone size was extremely small in a tention field, a large number of Gaussian points were is used for numerical integration of the Kernels. In order to estimate the contact zone size, iteration method was used. The interface crack tips with contact zones showed no oscillatory behavior and J-integral values across the interface were conserved.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1276-1279
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• 2007

The main objectives of the Load/Unload are no slider-disk contact and no media damage. But, it remains unsolved technical problems on the unloading process. While the slider climbs up the ramp at the outer edge of the disk, the possibility of the slider-disk contact by lift-off force and rebound of the slider increases. Keeping in mind of these points, to prevent the slider-disk contact, we apply the disk bump on disk outer edge proceeding unload. First, referring to the simulation results, we select the optimal bump shapes to improve unload performance by unload analysis. Second, the disk bump is mechanically manufactured by pressing disk surface using tungsten tips. The bumps are variously processed by changing pressing pressure of tungsten tips. After confirming bump shape by nano-scanner, the optimal bump shape is applied to experimental unload process. Through this experiment, it is conformed that the unload performance was improved by using the optimal disk bump to prevent the slider-disk contact.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.609-612
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• 2007

The HDD (hard disk drive) using Load/Unload (L/UL) technology includes the benefits which are increased areal density, reduced power consumption and improved shock resistance than those of contact-start-stop (CSS). Dynamic L/UL has been widely used in portable hard disk drive and will become the key technology for developing the small form factor hard disk drive. The main design objectives of the L/UL mechanisms are no slider-disk contact or no media damage even with contact during L/UL, and a smooth and short unloading process. In this paper, we focus on lift-off force, pitch static attitude (PSA), roll static attitude (RSA) and dimple point. The "lift-off" force, defined as the minimum air bearing force, is another very important indicator of unloading performance. A large amplitude of lift-off force increases the ramp force, the unloading time, the slider oscillation and contact-possibility. PSA and RSA are also very important parameters in L/UL system and stability of slider is mainly determined by PSA and RSA. Dimple point by PSA and RSA is also important indicator. Therefore we find the optimal dimple point of SFF HDD suspension for improving the unloading performance.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.18 no.1
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• pp.199-220
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• 2005

Objective : This study was performed to investigate the effects of Sophorae Radix and Coptidis Rhizoma-iontophoresis in allergic contact dermatitis. Methods : Contact hypersensitivity assay, video microscope, melanin-erythema levels, pH levels, hydration levels, WBC count, RBC count, neutrophil ratio, lymphocyte ratio and total IgE levels were measured. Results : At contact hypersensitivity assay, the right ear swellings in Sophorae Radix and Coptidis Rhizoma-iontophoresis group were decreased compared with control group, but have no statistical significance. At observation of skin morphologic change, many papules were seen in control group and keratins were seen in Sophorae Radix-iontophoresis group. At melanin levels, Sophorae Radix and Coptidis Rhizoma-iontophoresis groups showed no significant difference compared with control group. At pH levels, Sophorae Radix-iontophoresis group showed significant decreased with control group. At hydration levels, Sophorae Radix and Coptidis Rhizoma-iontophoreses groups showed to significant difference compared with control group. WBC count, RBC count and neutrophil ratio were significantly increased in Sophorae Radix and Coptidis Rhizoma-iontophoresis group compared with control group. Lymphocyte ratio and total IgE levels were significantly decreased in Sophorae Radix and Coptidis Rhizoma-iontophoresis groups compared with control group. At morphology of skin, inflammation was decreased and the thickness of epidermis was well preserved in Sophorae Radix and Coptidis Rhizoma-iontophoresis group. Conclusion : Sophorae Radix and Coptidis Rhizoma-iontophoresis had some anti-allergy, anti-inflammatory effects on allergic contact dermatitis, but had no effects on melanin-erythema levels, pH levels and hydration levels of skin.