• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.1
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• pp.57-62
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• 2014

Most analytical models of the human body have focused on conscious responses. A patellar tendon reflex, a representative example of spinal reflexes, occurs without a neural command. Muscle forces and activation of the quadriceps femoris muscles in healthy adults during patellar tendon reflex are identified in this study. The model is assumed to move in the sagittal plane, and the thigh and the trunk are assumed to be fixed in a sitting position so that the shank can move similar to a pendulum. The knee joint is modeled as a revolute joint, and the ankle joint is modeled as a fixed joint so that the shank and the foot can be regarded as one rigid body. Muscle forces are calculated following the inverse dynamic approach. Kinematic data obtained from an experiment (Mamizuka, 2007) are used as input data. Muscle activations are identified using a Hill-type muscle model. The obtained simulation results are compared with experimental results for validating the model and the underlying assumptions.

• Korean Journal of Human Ecology
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• v.17 no.1
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• pp.115-126
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• 2008

The construction of an athlete's tight-fitting garments is very important to the wearer in terms of athletic performance. Therefore pattern development of tight-fitting garments must allow for the full range of human movement and postures. In this study the relationship between the construction of a skate pants pattern and clothing fitting was explored with the aim of improving the comfort of the clothing. The four male subjects were university students between the ages of 20 to 24. Subjective wear sensations of the experimental garments were rated using a seven-point Likert scale on four consecutive days. While wearing the garments, subjects were asked to take five different postures including waist flexion, sitting and others. A Likert-type scale was used for the evaluation, with 7 points indicating the best fit in tight-fitting pants. Results showed differences in the front-rise length and back-rise length between basic pants(A) and modified pants(B,C,D) were -5.16cm and +5.64cm. Comparing the basic pants pattern(A) with modified pants pattern(B), the latter was superior to basic pants(A) in terms of pressure sensation and closeness of fit, but there was no significant difference. Among the four tight-fitting skate pants, A and B pants were superior to the others in terms of fitting and stability of waist and hip sections. In the case of the skate pants, the number of cutting lines in the pattern had an influence on clothing comfort. A minimum cutting line for tight skate pants was better than a maximum cutting line in terms of clothing comfort.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.3
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• pp.387-394
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• 1994

Journal of the Korean Society of Clothing and Textiles Vol. 18, No. 3 (1994) p. 387∼394 In this study, the restriction of slacks (blue jean) versus box pleats skirt was investigated, from the view point of peripheral blood flow at the toe according to motion variation and E.M.G. analysis of leg muscles after walking on the flat or going up and down stairways. Besides, the pressure of slacks on the lower extrimity was measured statically and dynamically. The main results were summerized as follows; 1. The clothing pressure applied by slacks was; each one of thigh and lower leg was 18.2 g/ cm2 and 22.1 g/cm2 in upright, 63.4 g/cm2 and 26.6 g/cm2 in sitting on the chair, on both sides of thigh and lower leg 272.0 g/cm2 over in squatting. 2. When the motion starts from upright, the dynamic clothing pressure reach their peak before the motions end. When the motion ends and the body comes to a still condition, the clothing pressure grow lower and indicate a constant value. but when the body starts moving again to return to upright, the pressures once grow higher and go to zero value after reaching the peak. The pressure on the knee show much greater than those on the hip. This can be because these pressures depend on the degree of skin stretching motion and of its curvature. 3. The surface E.M.G. in leg muscles M. rectus femoris and M. gastrocnemius were recoreded. In the case of wearing slacks, two muscles were activated much more than wearing skirt. 4. The peripheral blood flow at the toe by wearing slacks was lower than wearing skirt. Also the case when squatting, the peripheral blood flow at the toe was low.

• Physical Therapy Korea
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• v.17 no.2
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• pp.33-42
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• 2010

The aim of this study was to investigate correlations of the Trunk Control Test (TCT), Postural Assessment Scale for Stroke (PASS-TC), and Trunk Impairment Scale (TIS) and to compare the TCT, PASS-TC, TIS and its subscales in relation to balance, gait and functional performance ability after stroke. Sixty-two stroke patients attending a rehabilitation program participated in the study. Trunk control was measured with the use of TCT, PASS-TC, TIS balance (Berg Balance scale; BSS), gait ability (10 m walk test), functional performance ability (Tuned Up and Go Test TUG) and the mobility part of the Modified Barthel index (MBI), Fugl Meyer-Upper/Lower Extremity ($FM-U{\cdot}L/E$), The scatter-plot (correlation coefficient) was composed for the total scores of the TCT, PASS-TC, and TIS. The multiple regression analysis was performed to evaluate the impact of trunk control on balance, gait, and functional performance ability. Twenty eight participants (45.2%) and twenty participants (32.3%) obtained the maximum score on the TCT and PASS-TC respectively; no subject reached the maximum score on the Trunk Impairment Scale. There were significant correlations between the TIS and TCT (r=.38, p<.01), PASS-TC (r=.30, p<.05), TCT and PASS-TC (r=.59, p<.01). Stepwise multiple regression analysis showed that the BBS score (${\beta}=.420{\sim}.832$) had slightly more power in predicting trunk control than the $FM-U{\cdot}L/E$. TIS-dynamic sitting balance, TUG and the MBI-mobility part. This study 치early indicates that trunk control is still impaired in stroke patients. Measures of trunk control were significantly related with values of balance, gait and functional performance ability. The results imply that management of trunk rehabilitation after stroke should be emphasized.

• Clinical and Experimental Pediatrics
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• v.65 no.3
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• pp.142-149
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• 2022

Background: Individuals with Down syndrome present with several impairments such as hypotonia, ligament laxity, decreased muscle strength, insufficient muscular cocontraction, inadequate postural control, and disturbed proprioception. These factors are responsible for the developmental challenges faced by children with Down syndrome. These individuals also present with balance dysfunctions. Purpose: This systematic review aims to describe the motor dysfunction and balance impairments in children and adolescents with Down syndrome. Methods: We searched the Scopus, ScienceDirect, MEDLINE, Wiley, and EBSCO databases for observational studies evaluating the motor abilities and balance performance in individuals with Down syndrome. The review was registered on PROSPERO. Results: A total of 1,096 articles were retrieved; after careful screening and scrutinizing against the inclusion and exclusion criteria, 10 articles were included in the review. Overall, the children and adolescents with Down syndrome showed delays and dysfunction in performing various activities such as sitting, pulling to stand, standing, and walking. They also presented with compensatory mechanisms to maintain their equilibrium in static and dynamic activities. Conclusion: The motor development of children with Down syndrome is significantly delayed due to structural differences in the brain. These individuals have inefficient compensatory strategies like increasing step width, increasing frequency of mediolateral center of pressure displacement, decreasing anteroposterior displacement, increasing trunk stiffness, and increasing posterior trunk displacement to maintain equilibrium. Down syndrome presents with interindividual variations; therefore, a thorough evaluation is required before a structured intervention is developed to improve motor and balance dysfunction.

• The Journal of Korean Medicine
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• v.32 no.6
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• pp.10-17
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• 2011

Background: Vibration response imaging (VRI) is a new technology that records energy generated by airflow during the respiration cycle. Analysis of lung sound using VRI may overcome the limitations of auscultation. Objectives: To set a VRI standard for healthy Koreans, we conducted a clinical assessment to evaluate breath sound images and quantification in healthy subjects and compared the findings with reported breath sound characteristics. Methods: Recordings were performed using the VRIxp. Eighty subjects took a deep breath four times during a 12-second interval while sitting upright. The quantitative aspect was analyzed using the VRI quantitative lung data (QLD) for total left lung, total right lung and for six lung regions: left upper lung (LUL), left middle lung (LML), left lower lung (LLL), right upper lung (RUL), right middle lung (RML), right lower lung (RLL). The qualitative aspect was provided through image assessments by three reviewers. Results: In all regions the left lung had significantly higher QLD than the right lung (P<0.005, paired t-test). The inter-rater agreement was 0.78. 84% of the images were found normal by the final assessment. Among the 16% (n=13) of images with abnormal final assessment, the most common flawed features were dynamic image (77%, n=10) and maximum energy frame (MEF) shape (77%, n=10). No significant differences were found between males and females for QLD but there were significant differences in qualitative aspects including dynamic images, MEF shape, and missing LLL. Conclusion: The characteristics of healthy Koreans are similar to those of Western subjects reported previously. VRI is easy to use and objective, and so is helpful to diagnose patients with respiratory diseases and to monitor the progress of diseases after medical treatments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.253-260
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• 2020

This study aimed to compare the effects of sit-to-stand training, or training to stand up from sitting positions at various seat heights, on the balance recovery among stroke patients. This study included 20 stroke patients who were randomly divided into two groups. Each group was trained for six weeks, three times a week from March to June 2019. Static balance and dynamic balance were measured, and the variations were analyzed using the paired t-test and the independent t-test. There were significant changes observed in both static and dynamic balance (p<.05) before and after training. However, no significant changes were seen in the static balance in the standing posture with eyes closed (p>.05). This study confirmed that there was a significant effect of training on the balance of stroke patients, especially when progressively lower seat heights were used during the training. This suggests new directions for treatment during rehabilitation for balance recovery of stroke patients. Further studies will need to apply this training to a larger number of subjects, and use various training methods such as randomization of seat height to enable the generalization of the results of this study and application in clinical practice.

• Journal of Korea Entertainment Industry Association
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• v.15 no.7
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• pp.181-192
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• 2021

This study was conducted to investigate the effects of a participatory rehabilitation program on sit-rise and rise-to-walk test performances, and perception and motor skills in adults with medically vulnerable individuals and, adults with developmental disabilities in particular. Seventeen adults with developmental disabilities participated in a participatory rehabilitation program using resistance bands and exercise balls, for 60 minutes once weekly over 13 weeks. Their performances were measured before and immediately after the intervention, and 12 weeks after. The findings were as follows. In the sit-rise test, the number of times rising from sitting posture increased after the intervention versus before, but the difference was not statistically significant. In the rise-to-walk test, the performance showed statistically significant difference over time, and the post-hoc test showed a significant effect after the intervention versus before. There was no significant difference in perception and motor skills. In sum, the participatory rehabilitation program positively influenced dynamic balancing related to functional activities but had no significant effect on perception and motor skills, which is related to motor control and motor learning. It is suggested that to increase the participation in community activities, reduce fall risk, and improve dynamic balancing abilities in adults with developmental disabilities, participatory rehabilitation programs should be utilized to promote the physical wellbeing.

• Journal of Korea Entertainment Industry Association
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• v.13 no.8
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• pp.619-626
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• 2019

This study was conducted to investigate the effects of a participatory rehabilitation program on sit-rise and rise-to-walk test performances, and perception and motor skills in adults with medically vulnerable individuals and, adults with developmental disabilities in particular. Seventeen adults with developmental disabilities participated in a participatory rehabilitation program using resistance bands and exercise balls, for 60 minutes once weekly over 13 weeks. Their performances were measured before and immediately after the intervention, and 12 weeks after. The findings were as follows. In the sit-rise test, the number of times rising from sitting posture increased after the intervention versus before, but the difference was not statistically significant. In the rise-to-walk test, the performance showed statistically significant difference over time, and the post-hoc test showed a significant effect after the intervention versus before. There was no significant difference in perception and motor skills. In sum, the participatory rehabilitation program positively influenced dynamic balancing related to functional activities but had no significant effect on perception and motor skills, which is related to motor control and motor learning. It is suggested that to increase the participation in community activities, reduce fall risk, and improve dynamic balancing abilities in adults with developmental disabilities, participatory rehabilitation programs should be utilized to promote the physical wellbeing.

• Journal of Korea Water Resources Association
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• v.32 no.2
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• pp.185-195
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• 1999

The finite difference method and the method of characteristics are frequently used for the numerical analysis of kinematic wave model. Truncation errors cause the peak discharge dissipated in the solution from the finite difference method. The peak discharge is conserved in the solution from the finite difference method. The peak discharge is conserved in the solution from the method of characteristics, however, the shock may deteriorates the numerical solution. In this paper, distinctive features of each scheme are investigated for the numerical analysis of kinematic wave model, and applicability of shock fitting algorithm such as Propagating Shock Fitting and Approximated Shock Fitting methods are studied. Propagating Shock Fitting method appears to treat shock properly, however, it failed to fit the shock appropriately when applied to a sudden inflow change in a long river. Approximate Shock Sitting method, which uses finer elements, is found to be more proper shock-fitting than the Propagating Shock Fitting method. Comparisons are made between two solution from the kinematic wave theory with shock fitting and full dynamic wave theory, and the results are discussed.