• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.2 s.161
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• pp.258-268
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• 2007

The purpose of this research is to develop functional midsole that can restrain the heightening of plantar pressure in forefoot pressure so as to develop high-heeled shoes that can lessen foot ailments among women. The pumps shoes used for the research were of the same pumps type last. The variant was heel height, 3cm, 6cm, and 9cm, and the shoes were made in both normal midsole and functional midsole. The variant was applied to investigate the changes of foot pressure on forefoot and hindfoot according to heel height.'Heel Cup' was chosen for modification of functional midsolepumps type. to enlarge contact area in hindfoot, and 'Heel Posting Pad' was attached under sustentaculum tali to suppress the weight moving to forefoot pressure. If such functional parts are developed and used, it is possible to lessen the amount of Pmax or Impulse imposed by high-heeled pumps type on forefoot pressure. This can greatly lessen foot ailments, largely caused by high-heeled shoes, among women.

• ETRI Journal
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• v.42 no.1
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• pp.46-53
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• 2020

Gait analysis is an effective clinical tool across a wide range of applications. Recently, inertial measurement units have been extensively utilized for gait analysis. Effective gait analyses require good estimates of heel-strike and toe-off events. Previous studies have focused on the effective device position and type of triaxis direction to detect gait events. This study proposes an effective heel-strike and toe-off detection algorithm using a smart insole with inertial measurement units. This method detects heel-strike and toe-off events through a time-frequency analysis by limiting the range. To assess its performance, gait data for seven healthy male subjects during walking and running were acquired. The proposed heel-strike and toe-off detection algorithm yielded the largest error of 0.03 seconds for running toe-off events, and an average of 0-0.01 seconds for other gait tests. Novel gait analyses could be conducted without suffering from space limitations because gait parameters such as the cadence, stance phase time, swing phase time, single-support time, and double-support time can all be estimated using the proposed heel-strike and toe-off detection algorithm.

• Korean Journal of Applied Biomechanics
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• v.17 no.2
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• pp.83-91
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• 2007

This experiment studied the change in a human's control of his or her static posture by analyzing the stabilogram diffusion and, by using the said study, evaluated the control ability of different groups with different experiences. The postures had a rising requirement of heel-rise according to three conditions: heel-toe, ball, toe; the groups were divided into dance major student and non-dance majors. The results of the critical points according to posture did not show a direct relation with the change in postures that had a rising requirement of heel-rise. The diffusion coefficient(D) had greater stochastic activity for short-term regions that utilize open-loop controls without feedback than for long-term regions that used closed-loop controls with feedback to maintain balance. The directional results of the body undergoing disturbance showed that A/P direction's diffusion coefficient (D) was larger than that of M/L direction. Both feet's planar diffusion coefficients were a linear combination of the diffusion coefficients calculated for the x and y axis. In studying the different abilities to control posture between a dance major student and a non-dance majors, a comparison of open-loop control's diffusion coefficient(D) was effective, and dance major student had superior control ability to that of non-dance majors.

• Korean Journal of Applied Biomechanics
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• v.14 no.2
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• pp.105-119
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• 2004

To enhance our understanding of the loads on the foot during treadmill running, we have used a pressure-sensitive insole system to determine pressure, rate of loading and impulse distributions on the plantar surface during treadmill running, both in minimally cushioned footwear and in cushioned shoes. This report includes pressure, rate of loading, impulse and contact time data from a study of ten subjects running on a treadmill at 4.0m/s. Among heel-toe runners, the highest peak pressures and highest rates of loading were observed under the centre of the heel and in the medial forefoot. The arch regions were only lightly loaded. Contact time was greater in the forefoot than in the heel. Two-thirds of the impulse recorded during the step was the result of forces applied through the forefoot, mostly in the region of the metatarsal heads. The distribution of loads in the shoe suggests that the load distributing properties of the cushioning system are most important in the centre of the heel, under the metatarsal heads and great toe. Shock attenuation is primarily required under the centre of the heel and to lesser extent under the metatarsal heads. Some energy dissipation may be desirable in the heel region because it causes shock to be absorbed with less force. All the 'propulsive' effort is applied through the forefoot. Therefore, this region should as resilient as possible.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.10
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• pp.61-68
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• 2010

In order to let the humanoid robot walk on the uneven terrains, the robot's foot should have the similar structure and function as human's. The intelligent foot should be made up of toes and heel. When it walks on the uneven terrains, the foot's sole senses the force and adjusts foot's position before robot losing his balance. In this paper, the force sensors of robot's intelligent foot for having the similar structure and function like human are developed. The heel 3-axis force/moment sensor and toe force sensors for humanoid robot's intelligent foot is developed, and the characteristic tests of them are carried out. As a result of characteristic test, the interference error of the heel 3-axis force/moment sensor is less than 2.2%. It is thought that the developed force sensors could be used to measure the reaction forces which is applied the toes and the heel of a humanoid robot.

• Journal of the Korean Society of Physical Medicine
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• v.6 no.2
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• pp.135-143
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• 2011

Purpose: The purpose of this study was to investigate onset timing of vastus medialis oblique(VMO) relative to vastus lateralis(VL) the VMO/VL electromyographic(EMG) ratio according to heel height Methods: A repeated measures design was used. Fifteen healthy female college students with no known knee musculoskeletal dysfunction were recruited this study. They carried out a standardised stair acent activity under 4 conditions; barefoot, and with heel height of 1, 3, 7 cm. Muscle activity was measured by surface EMG (Myosystem 1400A, Noraxon Inc., U.S.A). Data were analysed using $1{\times}4$ repeated measures ANOVA. Results: Onset timing differed with heel height(p<.05). However, the VMO/VL EMG ratio was not significantly difference between conditions. Conclusion: We found that 7 cm heel height delayed in VMO onset compared with 3 cm heel height during stair ascent, but no change in the relative EMG intensity of VMO and VL as measured by th VMO/VL ratio. The findings indicate that high-heeled shoes may have disadvantages in knee stability because of delayed onset of VMO. Due to a lack of knee joint stability, wearing of high heeled shoes should be avoided.

• The Journal of Korean Physical Therapy
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• v.16 no.3
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• pp.112-124
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• 2004

Purpose : The purpose of this study is to research the effects of the differences in shoe heel height on balanced performances with a balance master. Method : 40 healthy female adults were divided into 2 groups at random. All the female participants were tested by a balance master system. Differences were analyzed according to high heel shoes and low heel shoes. The ability of static postural balance control was measured by modified CTSIB and unilateral stance test, while that of dynamic postural balance control was measured by LOS (limit of stability) and rhythmic weight shift, among the programs of a balance master. Result : 1. There is no significant correlation between the ability of static and dynamic postural balance control before main test without the shoes. 2. Movement velocity and directional control ability were significant correlation compared result of in high heel shoes and low heel shoes group. Conclusion : In conclusion, the test results of the high heeled shoe group and the low heeled shoe group through a balance master system showed that the former one is inferior to the latter one.

• Journal of the Ergonomics Society of Korea
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• v.23 no.1
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• pp.39-48
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• 2004

In terms of women engaged in clerical job. working time of the workers who mainly keep standing with their high-heeled shoes on has been increasing. According]y. they are exposed to many kinds of foot deformation caused by loads of lower back and lower extremities due to high-heeled shoes. The type of heels they usually wear are diverse though the hight is same. In this study. we investigated most women's favorite styles of shoes concerned with heights. types and contact areas of the heels. Hence. we designed three kinds of shoes for an experiment: their contact areas with ground are 1 cm2. 2-4 cm2 and over 9 cm2 according to the heel heights. respectively. To investigate the biomechanical effects. analysis of motion and EMG were applied to the experiments. In addition. foot pressure distribution was measured for more detailed analysis. Six healthy young women were participated in this experiments. The result showed the heel becoming higher and narrower increased not only fluctuation of CBM(Center of Body Mass). but also the load of low back muscle and lower extremities. Accordingly. there was significant difference among types of the heel in terms of the role supporting load of the body. though the height is same. Especially. the difference among the pressures on a foot was most significant. In conclusion. we verified biomechanical effects are related with the contact area of a heel with ground as well as the hight.

• The Journal of Korean Physical Therapy
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• v.19 no.6
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• pp.11-15
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• 2007

Purpose: This study examined the various patterns of standing to squatting activities, and reports the testing standard and phases for examining the standing to squatting position. Methods: One thousand, normal college students (500 males, 500 females) volunteered for this study. The patterns are performed by naked eye analysis with two video cameras. Results: The patterns from the standing to squatting position are as follows 1. parallel with the heel on the pattern: 2. parallel with the heel off the pattern: 3. closed with the heel on the pattern: 4. closed with the heel on the pattern: 5. open with the heel on the patternand 6. open with the heel on the pattern. Conclusion: The phases of the standing to squatting position are as follows: phase I from standing to the anterior parts of the knees reaching the anterior limit of the BOS, phase II from phase I until the height of the hip and knee joints are the same, phase III from phase II until there was no full squatting and the heels broke contact with the floor and phase IV from phase III full squatting on the heels in contact with the floor.

• Journal of the Korean Society of Physical Medicine
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• v.10 no.2
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• pp.9-16
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• 2015

PURPOSE: The objective of this study was to identify the effects of shoulder abduction strength and EMG activities of the selected scapular and shoulder muscles during isometric shoulder abduction. METHODS: Thirty-four healthy young females were recruited for this study. Surface EMG equipment with inline force sensor was used to determine the shoulder abductor strength and the activity of the serratus anterior (SA), upper trapezius (UT), lower trapezius (LT), and middle deltoid (MD) during three shoe heel height conditions: (1) barefoot, (2) 3-cm shoe heel height, and (3) 7-cm shoe heel height. RESULTS: Isometric shoulder strength showed statistically significant difference among the conditions (p<0.05), and post-hoc test showed lower strength during the 7-cm condition ($49.98{\pm}17.56kg$) than during the barefoot ($44.97{\pm}20.15kg$) and 3-cm conditions ($36.59{\pm}17.07kg$). Furthermore, EMG activities of the SA, UT, and MD appeared to be statistically significantly different among the conditions, with lower values in the 7-cm condition compared to the barefoot condition (p<0.05). EMG ratios (MD/UT and SA/UT) were lower during the 7-cm condition than during the barefoot condition (p<0.05). CONCLUSION: These findings suggest that isometric shoulder abduction strength and EMG activities of scapular and shoulder muscles may be adversely changed with increasing shoe heel height.