• 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.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.601-608
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• 2006

The important elements in pavement design criteria are the stress and strain distributions. To obtain reasonable stress and strain distribution, tire contact area and tire pressures are very important. In this study, finite element analysis was used to identify the three-dimension states using nonlinear tire contact pressure and measured tire contact area. Measured tire contact area was quite different from the assumed tire contact area, and it resulted in different strain states under the tire. At the surface course, considering tire rib and nonlinear tire pressure, the pavement response presented accurate data compared to the predicted one. However, at the binder course, tire effects were generally negligible and it showed that the predicted pavement response was different compared to the measured one.

• Transactions of the Society of Information Storage Systems
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• v.10 no.1
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• pp.14-18
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• 2014

Adhesion between carbon nanotube (CNT) arrays is measured and characterized for number of different contact areas. The CNT arrays are directly grown on an electrostatic microactuator, and they make contact with each other during the growth process. The pull-out force is precisely applied by the microactuator while the contact status is identified by measuring electrical resistance between the CNT arrays. We have designed different contact areas of 1000, 6000, and 8500 ${\mu}m^2$ between the CNT arrays, and the corresponding adhesion increases from 0.9 to 3.7 ${\mu}N$ as the contact area increases.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.4
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• pp.508-515
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• 2010

This study was conducted on male college students with supinated foot to measure the foot pressure by having them wear three kinds of wedge insoles ($0^{\circ}$, $3.5^{\circ}$, $7^{\circ}$). Foot contact time, foot contact area, peak pressure and mean pressure were measured using a foot pressure distribution measuring instrument. And the surface of the foot sole was divided into 10 areas. Regarding foot contact time, there was no statistically significant difference by showing $0.69{\pm}0.004$ seconds at $3.5^{\circ}$ and $0.68{\pm}0.006$ seconds at $0^{\circ}$ and $7^{\circ}$. Regarding the foot contact area, it appeared broad in the inside area of the foot according to wedge insole, and there was statistically significant difference in the area 1 of the rear foot(p< .01) and the area 3 of the middle foot(p< .05). The peak pressure by foot area decreased in the outside of the foot according to wedge insole, while increasing in the inside of the foot. Among the areas, there was statistically significant in the area 2 of the rear foot (p< .01) and the area 3 of the middle foot (p< .05). Regarding the mean pressure by foot area, the pressure roughly increased in the inside area of the foot according to wedge insole, while decreasing in the outside of the foot.

• Journal of the Korean Society for Railway
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• v.9 no.5 s.36
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• pp.618-623
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• 2006

Understanding the contact between wheel and rail is a starting point in railway vehicle dynamic research area and especially analysis for the contact geometry between wheel and rail is important. On the one hand, the critical speed as the natural characteristics of rolling-stock is generally tested on the roller rig. The geometrical characteristics of the wheel/roller contact on the roller rig are different from these of the general wheel/rail contact because the longitudinal radius of roller is not infinite compared with rail. Thus, in this paper we developed the algorithm to analyze the wheel/roller contact geometry of our roller rig which is constructed now and analyzed the difference between whee/roller contact and wheel/rail contact. In conclusion, we found that the yaw motion of wheelset and the roller radius influence the geometrical contact parameters in wheel flange contact area.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.3
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• pp.33-41
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• 2014

Fretting is a kind of surface degradation mechanism observed in mechanical components and structures. When two pieces of materials, pressed together by an external static load, are subjected to a transverse cyclic loading or various vibrations, so that one contacting face is relatively displaced cyclically parallel to the other face, wear of the mating surfaces occurs. These fretting damages may be observed in electrical connectors for automotive components, where there are special environments and various vibration conditions. This study aims to evaluate the usefulness of fretting test equipment that was developed for reliability test of electrical connector. Fretting tests were carried out using tin coated connectors and friction force, contact resistance, contact area and roughness of contact region were investigated. The following results that will be helpful to understand the fretting wear mechanism, increase process the contact resistance and contact area were obtained. (1) In the same frequency and slip amplitude, the friction force, roughness and contact area increased rapidly until about $10^3$ cycles, after which it was slightly changed. (2) In the various frequency and slip amplitude, the contact area increased with slip amplitude and cyclic numbers, but it did not depend on cyclic frequency. (3) The surface roughness of contact region did not depend on the cyclic frequency. From these results, the applicability of the fretting wear test equipment and reliability of connector were discussed.

• Nuclear Engineering and Technology
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• v.54 no.8
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• pp.2989-2998
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• 2022

Line contact structures, such as the contact between graphite brick and graphite tenon, widely exist in high-temperature gas-cooled reactors. Due to the stress concentration effect, the line contact area is one of the dangerous positions prone to failure in the nuclear reactor core. In this paper, the failure mechanism of line contact structures composed of IG11 nuclear graphite column and brick were investigated by means of experiment and finite element simulation. It was found that the failure process mainly includes three stages: firstly, the damage accumulation in nuclear graphite material led to the characteristic yielding of the line contact structure, but no macroscopic failure can be observed at this stage; secondly, the stresses near the contact area met Mohr failure criterion, and a crack initiated and propagated laterally in the contact zone, that is, local macroscopic failure occurred at this stage; finally, a second crack initiated in the contact area and developed in to a Y-shape, resulting in the final failure of the structure. This study lays a foundation for the structural design and safety assessment of high-temperature gas-cooled reactors.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.405-412
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• 1998

According to the relative stiffness between the half-space and plate or loading condition, some parts of the plate can be separated from the half-space. The finite element procedure to determine the contact area by considering the distribution of contact pressure between plate and the elastic half-space is developed. The vertical surface displacements of the elastic half-space can be obtained through the integrations of the Boussinesq's solution for a point load. The rectangular plate on the elastic half-space is modeled by the 8-node rectangular and 6-node triangular elements and the Mindlin plate theory is used in oder to consider the transverse shear effect. In this study, the contact area may be determined approximately by the analysis with rectangular elements. From this results, the mesh pattern is modified by using triangular and rectangular elements. The contact area can be determined by the new mesh pattern with a relatively sufficient accuracy.

• Journal of the Korean Wood Science and Technology
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• v.39 no.5
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• pp.437-443
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• 2011

In Korea, there has been a traditional post and beam wood construction with large roof load. Because a large friction is generated in wooden joint or members, it is important to evaluate the friction between wood members according to wood direction. Because most of studies have been concerned with friction between wood and steel, excluding effect of real area of contact, there are a few studies on the friction between wood members. The object of this study was to evaluate friction or coefficient of friction according to normal force and real area of contact of wood. With Japanese larch (Larix kaempferi) test specimens, five steps of normal force and combinations of test were prepared. Results indicated that normal force had almost no affection on the friction, however there was difference about friction or coefficient of friction according to real contact conditions of wood grain and contact area.

• Korean Journal of Health Education and Promotion
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• v.4 no.1
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• pp.65-75
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• 1987

This study was conducted (i) to recommend the high-scored education method as a adaptable method, and (ii) to find the most influential factor among the three acceptability components (feasibility factor, stimulation factor and reliability factor) to urban or rural residents. The accept-ability score of each health education method currently existing in urban and rural area was estimated. A total of 257 households in Guro 6-dong, Seoul, and 233 households in Jeomdong-myeon, Yeoju-gun, were sampled by interview survey using questionnaire. The four types of health education methods used in this study are; printed matter method, mailing service method. personal contact method, and group contact method. The major findings obtained from this research are as follows; 1) In urban area, the highest-scored in terms of acceptability is the personal contact method, followed by the mailing service, the printed matter, and the group contact. The mailing service method is found to be effective especially for the intelligent group people. 2) In rural area, the highest-scored in terms of acceptability is also the personal contact method, followed by the group contact, and printed matter method. In general, the group contact method is effective toward both urban-poor and rural housewives (especially in stimulation factor). To improve the health consciousness of the residents, there arises the need for the existing education program into better organized and diversified one and for educating health-educators by providing in-depth health knowledge.