• Physical Therapy Korea
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• v.25 no.4
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• pp.9-18
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• 2018

Background: Leg length discrepancy (LLD) leads to many musculoskeletal disorders and affects daily activities such as walking. In the majority of the population, mild LLD is a common condition. Nevertheless, it is still controversy among researchers and clinicians on the effects of mild LLD during gait, and available studies have largely overlooked this issue. Objects: The purpose of the present study is to investigate the effects of mild LLD on the gait parameters and trunk acceleration. Methods: A total of 15 female and male participants with no evidence of LLD of >.5 ㎝ participated in the present study. All participants walked under the following two conditions: (1) The non-LLD condition, where the participants walked in shoes of the same heel height; (2) A mild LLD condition induced by wearing a 1.5 ㎝ higher heel on the right shoe. The GAITRite system and tri-axial accelerometer were used to measure gait parameters and trunk acceleration. To compare the variation of each variable, a paired t-test was performed. Results: Compared to the non-LLD condition, step time and swing phase were significantly increased in the mild LLD condition, while stance phase, single support phase, and double support phase significantly decreased in the short limb (p<.05). In the long limb of the mild LLD condition, single support phase significantly increased, while swing phase significantly decreased (p<.05). Furthermore, significant decrease in the gait velocity and cadence in the mild LLD condition were observed (p<.05). In the comparison between both limbs in the mild LLD condition, the step time and swing phase of the short limb significantly increased compared with the long limb, while step length, stance phase, and single support phase of the long limb significantly increased compared with the short limb (p<.05). Additionally, trunk acceleration of all directions (anterior-posterior, medial-lateral, vertical) significantly increased in the mild LLD condition (p<.05). Conclusion: The results of the present study demonstrate that mild LLD causes altered and asymmetrical gait patterns and affects the trunk, resulting in inefficient gait. Therefore, mild LLD should not be overlooked and requires adequate treatment.

• Korean Journal of Applied Biomechanics
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• v.19 no.1
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• pp.159-166
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• 2009

The purpose of this study was to develop and automatic gait event detection algorithm using single accelerometer which is attached at the top of the shoe. The sinal vector magnitude and anterior-posterior(x-axis) directional component of accelerometer were used to detect heel strike(HS) and toe off(TO), respectively. To evaluate proposed algorithm, gait event timing was compared with that by force plate and kinematic data. In experiment, 7 subjects performed 10 trials level walking with 3 different walking conditions such as fast, preferred & slow walking. An accelerometer, force plate and 3D motion capture system were used during experiment. Gait event by force plate was used as reference timing. Results showed that gait event by accelerometer is similar to that by force plate. The distribution of differences were spread about $22.33{\pm}17.45m$ for HS and $26.82{\pm}14.78m$ for To and most error was existed consistently prior to 20ms. The difference between gait event by kinematic data and developed algorithm was small. Thus it can be concluded that developed algorithm can be used during outdoor walking experiment. Further study is necessary to extract gait spatial variables by removing gravity factor.

• Journal of the Korean Society of Physical Medicine
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• v.12 no.3
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• pp.85-91
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• 2017

PURPOSE: The purpose of this study was to compare muscle activation of the trunk and lower limbs of subjects wearing high-heeled or flat shoes while crossing over obstacles of different heights. METHODS: Twenty subjects participated in this study. While wearing high-heeled shoes (7 cm) or flat shoes (0 cm), the subjects were asked to cross over obstacles of different heights (10%, 20%, and 30% of their lower-limb length). Muscle activation of the trunk and lower limbs with the supported side while crossing over obstacles of different heights was measured using the electromyogram (Noraxon, DTS, Germany). Two-way repeated ANOVA was used to compare the muscle activation between high-heel shoes and flat shoes while crossing over obstacles of different heights. All statistical analyses were performed using SPSS ver. 21, and p-values less than .05 were used to identify significant differences. RESULTS: As an obstacle's height increased, muscle activation of the trunk and lower limbs with the supported side was increased while wearing either type of shoe, and it was generally higher while wearing high-heeled shoes. However, tibialis anterior muscle activity while wearing high-heeled shoes was lower than while wearing flat shoes. CONCLUSION: This study showed that muscle activation of the trunk and lower limbs was higher when subjects wore high-heeled shoes than when they wore flat shoes while crossing over obstacles of different heights. Therefore, high-heeled shoes can easily cause high muscle fatigue of the trunk and lower limbs, and the TA muscle may weaken in persons who wear high-heeled shoes.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.21 no.2
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• pp.39-46
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• 2015

Background: The purpose of this study was to investigate the influence of short-term treadmill walking with high-heeled shoes on electromyography activities of the medial gastrocnemius, lateral gastrocnemius and tibialis anterior in healthy young females. Methods: Fifteen healthy females were recruited for this study. To measure muscle activation, the subjects were asked in random order to walk on a treadmill using either high-heeled shoes or barefoot conditions. The shoe heel height for high-heeled walking was 7 cm. The walking speed on the treadmill was 4 km/h, and the inclination rate of the treadmill was 10%. The subjects performed treadmill walking in the barefoot and high-heeled walking conditions for 5 minutes. Electromyography data were collected from the tibialis anterior, medial gastrocnemius, lateral gastrocnemius, and soleus on both firm and foam surfaces and during eyes-open and-closed conditions while standing. Results: Tibialis anterior activity was significantly different before and after the walking task while standing on a foam surface with eyes closed (p<.05). Conclusion: This finding suggests that the activity of the tibialis anterior may be lowered after high-heeled walking. Therefore, high-heeled shoes contribute to harmful effects at the ankle joints, increasing the risks of falling and musculoskeletal injury.

• Korean Journal of Applied Biomechanics
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• v.27 no.2
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• pp.133-140
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• 2017

Objective: The purpose of this study was to determine the relationship between center of pressure (CoP) and local stability of the lower joints, which was calculated based on approximate entropy (ApEn) during walking in elderly women. Method: Eighteen elderly women were recruited (age: $66.4{\pm}1.2yrs$; mass: $55.4{\pm}8.3kg$; height: $1.56{\pm}0.04m$) for this study. Before collecting data, reflective marker triads composed of 3 non-collinear spheres were attached to the lateral surface of the thigh and shank near the mid-segment to measure motion of the thigh and shank segments. To measure foot motion, reflective markers were placed on the shoe at the heel, head of the fifth metatarsal, and lateral malleolus, and were also placed on the right anterior-superior iliac spine, left anterior-superior iliac spine, and sacrum to observe pelvic motion. During treadmill walking, kinematic data were recorded using 6 infrared cameras (Oqus 300, Qualisys, Sweden) with a 100 Hz sampling frequency and kinetic data were collected from a treadmill (Instrumented Treadmill, Bertec, USA) for 20 strides. From kinematic data, 3D angles of the lower extremity's joint were calculated using Cardan technique and then ApEn were computed for their angles to evaluate local stability. Range of CoP was determined from the kinetic data. Pearson product-moment and Spearman rank correlation coefficient were applied to find relationship between CoP and ApEn. The level of significance was determined at p<.05. Results: There was a negative linear correlation between CoP and ApEn of hip joint adduction-abduction motion (p<.05), but ApEn of other joint motion did not affect the CoP. Conclusion: It was conjectured that ApEn, local stability index, for adduction/abduction of the hip joint during walking could be useful as a fall predictor.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.7
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• pp.1173-1183
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• 1997

In order to flatter the figures of average middle aged women by determining harmonious proportions for their costume forms, this study evaluates effects of varying design details of jackets(coats) with blouses and slacks using a ranking test and paired comparisons test. The result from clothing design C-2 which has the best design effect were as follows; 1. In order to look taller, the jacket(coats) is divided vertical long line and it has the emphasis point close to the face. 2. In order to make shoulder width look wider, armhole seam line attached 1-2 cm from the shoulder point. 3. In order to make chest width look slimmer, division was made up of a tailored collar with a deep V-neckline. 4. In order to make waist circumference look slimmer, the jacket has more fitted waist line than loosed it and tailored collar with a deep V-neckline. 5. In the case of the division of upper and lower garments, when the division was closer to the golden section, i.e., when the jacket hemline is hipline and slacks length is the heel excluded length of shoe heels, the overall appearance was better. 6. The V-neckline looked better, when it was cut along a long acute angle to the waist line. Because of dividing along above factors 1-6 i.e., clothing design C-2 was overall harmonious. Appropriate division of costume forms made for an aesthetic composition, which flattered the body types of middle aged women and presented harmonious, beautiful costume design effects. It made the women look taller, slim and balanced, and highlighted middle aged women's sense of beauty.

• Journal of the Ergonomics Society of Korea
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• v.27 no.3
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• pp.71-79
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• 2008

Walking shoes for walking and jogging have been used to enjoy lots of leisure time. Functional shoes such as walking shoes have special functions to improve body motility by changing of shoe shapes. The walking shoes could improve the motility by structural transformation of outsole as increase degrees of heel and toe. The study on insoles has not been conducted enough on the contrary of the study of outsole. The purpose of this study is to perform ergonomics analysis whether the Arch Supported insoles have an improving effect of muscle activities or not. Experiments were performed with 6 subjects who are health and haven't experienced any diseases past. EMG(Electromyography) and Foot Pressures were measured repeatedly for 5 seconds at 0 hour, after 1 hour and after 2 hours of walking. Insoles used for experiment are normal insole, insole inserted Arch Support and pad. The electrodes for EMG measurement were set on waist (erector spinae), and thigh (vastus lateralis), calf (gastrocnemius). Evaluations of EMG were analyzed by shift of MF (Median Frequency) and MPF (Mean Power Frequency). Foot Pressure was analyzed by mean pressure of feet and change of walking time. As results, Arch Support insole had larger frequency shift value than that of normal insole. Frequency shift between Arch Support insoles and normal insole showed significant difference on 95% confidence interval. And insole 1 has the highest value of frequency shift. For results of foot pressure, Arch Support insoles show continuous decreasing tendency when comparing with normal insoles by changing of times. Also, insole 1 has the highest decreasing value of foot pressure. Therefore, this study presented that the Arch Support insole can promote muscle activities and improves comfort for a prolonged walking.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.615-627
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• 2017

The purpose of this study is to identify the physical and psycho-social effects of self-foot reflexology on female college students wearing high heels. The research design used was the nonequivalent control group pretest-posttest design. A total of sixty-eight participants were assigned to the experimental group (n=35) or control group (n=33). Data were collected at baseline and after 6 weeks and 10 weeks. The data were analyzed using descriptive statistics, the chi-square test, t-test, and repeated measures ANOVA with the SPSS WIN 20.0 program. In the analysis of the physical effects of self-foot reflexology, there were significant interactions of group by time in terms of the lower extremity edema and fatigue (p<.05). In the analysis of the psycho-social effects of self-foot reflexology, there were significant interactions of group by time in terms of the perceived health status and self-efficacy (p<.05), except for health promoting behavior. Self-foot reflexology was effective in reducing lower extremity edema and fatigue and in improving the perceived health status and self-efficacy. Consequently, self-foot reflexology as a nursing intervention was found to be a method of providing female college students wearing high heels with physical and psycho-social relief.

• The Journal of the Korea Contents Association
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• v.12 no.6
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• pp.182-190
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• 2012

Based on the study, the issues and trends in the current functional sandal designs on the same product line will be examined for the future developments for the functional sandals and the results were obtained as follows. First, the sandals must have a high front heel with wide floors that meet the ground. Second, the preference for the chromatic colour is stronger than the achromatic colors. Third, the sandals must be designed in curves in terms of the height and shape of the heels and design must consider the shoe's balance. Fourth, the product must appear big to provide a sense of stability. However, the sandals must not be designed too big to make them look crude or cause inconvenience while exercising. Fifth, the sandals must not be designed in too complex ways. This study has investigated and analyzed the external design of functional sandals and the user reviews on the actual sandals were not done. Through more detailed studies, the diversity in the design of functional sandals must be south and Korea's competitive edge in the industry and design must be secured for the future.

• Conservation Science in Museum
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• v.26
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• pp.119-142
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• 2021

The gilt-bronze-and-silver shoes, excavated from the Tomb of King Muryeong, revealed many defective parts, which constantly raised in-depth re-investigation and reporting. In that point, scientific treatment and analysis were conducted to investigate the manufacturing techniques applied. The conservation treatment was carried out with an emphasis on the restoration of the original form and joining parts. As a result, the upper part of the right shoe and some part of the back heel were joined, confirming the joining method and the number of rivet used for instep bonding. From the component analysis, it is presumed that the outer plate was gilded with mercury amalgam on pure copper, and pure silver was used for the inner plate. The main pattern of the gilt-bronze-and-silver shoes includes designs of phoenix, lotus, and six-petal flower, while the lotus pattern is high in terms of ratio. Thus, youngnaksa(twisted gilt-bronze thread), geumdongsa(gilt-bronze thread), wondujeong (rivet), and samyeonjeong(quadrangular cleats) were used for bonding each plate. Twisted gilt-bronze thread was used to join the inner and outer plates, while the center and rear of the inner plate were combined with only gilt-bronze threads. From the fact, it is presumed that the joining method was different whether the function was decoration or just bonding. Regarding the manufacturing process, traces of burnishing were confirmed on the outer surface of the gilt-bronze and silver shoes, but no burnishing traces were identified on the inner surface of the silver plate, which is likely to prove more importance put on the finishing of the outer plates rather than that of the inner.