• Wind and Structures
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• v.14 no.3
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• pp.253-283
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• 2011

This paper presents the field measurement results of wind effects on a super-tall building (CITIC Plaza, 391 m high) located in Guangzhou. The field data such as wind speed, wind direction and acceleration responses were simultaneously and continuously recorded from the tall building by a wind and vibration monitoring system during two typhoons. The typhoon-generated wind characteristics including turbulence intensity, gust factor, peak factor, turbulence integral length scale and power spectral density of fluctuating wind speed were presented and discussed. The dynamic characteristics of the tall building were determined based on the field measurements and compared with those calculated from a 3D finite element model of the building. The measured natural frequencies of the two fundamental sway modes of the building were found to be larger than those calculated. The damping ratios of the building were evaluated by the random decrement technique, which demonstrated amplitude-dependent characteristics. The field measured acceleration responses were compared with wind tunnel test results, which were found to be consistent with the model test data. Finally, the serviceability performance of the super-tall building was assessed based on the field measurement results.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.5
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• pp.463-474
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• 2003

In this research, adult women＇s shoulder types were Classified through direct and indirect measurements to present a judging individual body size according to the type. Also, regression formula by shoulder types were calculated and presented the basic bodice pattern. The results were as follows: 1. The result of factor analysis indicated that 6 factors were extracted through factor analysis and those factors comprised 66.1 to of total variance. 2. By using factor scores, cluster analysis was carried out and subject were classified into 5 clusters. Type 1 was the inclined shoulders, wide shoulders and passive posture. Type 2 was the front type shoulders and active posture. Type 3 was the thick shoulders and back type shoulders. Type 4 was the narrow shoulders. Type f was the drooped shoulders, thin shoulder and sway posture. 3. The body types of individuals were judged by discriminant analysis. 4. After setting 4 items such as the bust girth, posterior waist length, neck base girth and waist girth as representative items and regression formulas were presented. the superiority of the final basic bodice patterns were demonstrated by high approval rate of the subjects who participated in testing.

• Korean Journal of Applied Biomechanics
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• v.18 no.2
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• pp.65-74
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• 2008

The purpose of this study was to investigate the effect on postural control and shooting record by archers of the balance exercise program for 12-weeks based on sprinter/skater pattern. the subject were 12 female archers(the control group 6, the experimental group 6) and the motion was measured using active balance system. the results were as follows. 1. Static postural controllability of archers was improved to reduce the whole path length and the sway of the COBx, COBy after the balance exercise program for 12-weeks based on sprinter/skater pattern. 2. Dynamic postural controllability of archers was improved to reduce the whole path length after the balance exercise program for 12-weeks based on sprinter/skater pattern. 3. Archers' postural controllability was improved when shooting after 12-week balance exercise program based on sprinter/skater pattern. but not effect shooting record.

• The Journal of Korean Physical Therapy
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• v.25 no.5
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• pp.232-238
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• 2013

Purpose: The aim of this study was to evaluate the effect of lumbar stabilization exercise on an unstable surface on trunk posture and static standing balance ability in patients with scoliosis. Methods: Subjects included 18 patients who showed symptom of scoliosis. Patients were divided into two experimental groups, one using an unstable surface and one using a fixed surface, and the patients were required to perform a lumbar stabilization exercise a total of 12 times for 60 minutes per session, three times per week for a period of four weeks, with a six-months follow-up period. Results: A significant reduction was observed in the group that performed the lumbar stabilization exercise on an unstable surface (p<0.05). A significant decrease in both the condition of closed eyes or open eyes in the left and right directions was observed in the group that performed the lumbar stabilization exercise on an unstable surface (p<0.05). After six months, results of comparison of the length of both sides of the trunk showed a significantl decrease in the group performing lumbar stabilization exercises on an unstable surface. Conclusion: Lumbar stabilization exercise on an unstable surface improved the trunk posture of patients with scoliosis symmetrically, and static balance ability in a standing posture showed improvement. In the future, lumbar stabilization exercise on an unstable surface may be used as an exercise for posture correction and balance increase for patients with scoliosis.

• Safety and Health at Work
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• v.6 no.3
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• pp.206-210
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• 2015

Background: Fatigue has a strong impact on workers' performance and safety, but expedient methods for assessing fatigue on the job are not yet available. Studies discuss posturography as an indicator of fatigue, but further evidence for its use in the workplace is needed. The purpose of the study is to examine whether posturography is a suitable indicator of fatigue in clerical workers. Methods: Thirty-six employees (${\emptyset}$ 34.8 years, standard deviation = 12.5) participated in postural tasks (eyes open, eyes closed, arm swinging, and dual task) in the morning and afternoon. Position of their center of pressure (COP) was registered using a Nintendo Wii Balance Board and commercial software. From registered COP time series, we calculated the following parameters: path length (mm), velocity (mm/s), anterior-posterior variance (mm), mediolateral variance (mm), and confidence area ($mm^2$). These parameters were reduced to two orthogonal factors in a factor analysis with varimax rotation. Results: Statistical analysis of the first factor (path length and velocity) showed a significant effect of time of day: COP moved along a shorter path at a lower velocity in the afternoon compared with that in the morning. There also was a significant effect of task, but no significant interaction. Conclusion: Data suggest that postural stability of clerical workers was comparable in the morning and afternoon, but COP movement was greater in the morning. Within the framework of dynamic systems theory, this could indicate that the postural system explored the state space in more detail, and thus was more ready to respond to unexpected perturbations in the morning.

• Journal of the Korean Society of Physical Medicine
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• v.9 no.3
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• pp.315-324
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• 2014

PURPOSE: This study aimed to determine the correlation of weight bearing ability at the affected side with balance and gait abilities for the development of pressure biofeedback based equipment to stroke patients. METHODS: This study included 35 patients with stroke patient. The tests were conducted to determine the weight bearing ratio while pushing a step forward the affected side, static balance ability using the total length of COP(Center of pressure), sway velocity of COP, COP velocity at the X and Y axis. Functional reaching test (FRT), berg balance scale (BBS) were used to assess the dynamic balance ability and timed up and go test (TUG), 10m walk test (10mWT) were used assess the gait ability respectively. In order to determine the correlation between measured variables, bivariate correlation analysis was conducted. RESULTS: A significant correlation of the weight bearing ratio were shown with COP total length and velocity(r=-.34), Y-axis velocity(r=-.39), FRT(r=.42), BBS(r=.54), TUG (r=-.39), and 10m walking test (r=-.42). CONCLUSION: This study result showed that as patients with stroke had more weight bearing ratio at the affected side, not only their static and dynamic balance abilities increased more but also functional gait ability improved more. These results mean that, to improve stroke patients' static, dynamic balance ability and gait ability, weight bearing training with the affected side foot placed one step forward necessary for gaits are important.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.580-583
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• 2018

Purpose: The purpose of this study was to compare the effects of ankle balance training on unstable and stable surfaces to discover on which surface the proprioception, balance and muscle strength of obese middle aged women improves more. Method: 30 obese middle-aged women were randomly recruited and divided into two groups (training on an unstable surface, training on a stable surface). The subjects in each group participated in the training for six weeks, three times per week for 30 minutes each session. Proprioception was measured using Dualer IQ digital inclinometer; sway length (SL) and sway area (SA) of center of pressure, and limit of stability (LOS) were measured for balance; muscle strength before and after the training was measured using manual muscle testing. Results: There were significant improvements in the subscales of the proprioception, balance and muscle strength in those who participated in ankle balance training on the unstable surface, and in those who participated on the stable surface. Therefore, the training of participants on unstable and stable surfaces did not identify which ankle balance training technique was more effective. Conclusion: Unstable and stable surface ankle balance training are both effective in improving the proprioception, balance and muscle strength of obese middle-aged woman.

• Physical Therapy Korea
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• v.22 no.3
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• pp.81-90
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• 2015

This study aimed to determine the effects of Rhythmic Auditory Stimulation (RAS) using music and a metronome on the gait of stroke patients. 13 female and 15 male volunteers were randomly allocated to two groups: namely a group to receive RAS using music and a metronome group (the experimental group; $n_1=14$) and a group to receive RAS using a metronome only (the control group; $n_2=14$). The affected side was the left side in 15 subjects and the right side in 13 subjects. The mean age of the subjects was 56.6 years, and the mean onset duration of stroke was 8.6 months. Intervention was applied for 30 minutes per session, once a day, 5 times a week for 4 weeks. To measure the patients' gait improvement, we measured gait velocity, cadence, stride length, double limb support using GAITRite, body center sway angle using an accelerometer, and Timed Up-and-Go test. Functional Gait Assessment were conducted before and after the experiment. The paired t-test was used for comparisons before and after the interventions in each group. Analysis of covariance was used for comparisons between the groups after the interventions. Statistical significance was set at ${\alpha}=.05$. Within each of the two groups, significant differences in all of the dependent variables before and after the experiment (p<.05) were observed. However, in the comparison between the two groups, the experimental group showed more significant improvements in all dependent variables than the control group (p<.05). Our results also suggest that in applying RAS in stroke patients, the combination of music and a metronome is more effective than using a metronome alone in improving patients' gait.

• Korean Journal of Applied Biomechanics
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• v.19 no.1
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• pp.107-115
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• 2009

The purpose of this study were to investigate the effects of muscle, balance and walking training on muscle, balance and gait kinematics in children with Down syndrome. Nine children ($9{\sim}12$ years old) with Down syndrome participated in this study. The participant with Down syndrome participated in muscle, balance and walking training for 12 weeks, three times a week Kinematic variables of gait were measured 3-dimentional motion capture system. The results indicated that the pelvis rotation decreased, the knee and hip flexion increased, decreased leg sway during the swing phase, the cadence increased, and the stride length decreased after the muscle, balance and walking training. In conclusion, Down syndrome's gait kinematic variables improved after the muscle, balance and walking training.

• Structural Engineering and Mechanics
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• v.43 no.5
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• pp.637-655
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• 2012

In this study, stochastic responses of a cable-stayed bridge subjected to the spatially varying earthquake ground motion are investigated by the finite element method taking into account soil-structure interaction (SSI) effects. The considered bridge in the analysis is Quincy Bay-view Bridge built on the Mississippi River in between 1983-1987 in Illinois, USA. The bridge is composed of two H-shaped concrete towers, double plane fan type cables and a composite concrete-steel girder deck. In order to determine the stochastic response of the bridge, a two-dimensional lumped masses model is considered. Incoherence, wave-passage and site response effects are taken into account for the spatially varying earthquake ground motion. Depending on variation in the earthquake motion, the response values of the cable-stayed bridge supported on firm, medium and soft foundation soil are obtained, separately. The effects of SSI on the stochastic response of the cable-stayed bridge are also investigated including foundation as a rigidly capped vertical pile groups. In this approach, piles closely grouped together beneath the towers are viewed as a single equivalent upright beam. The soil-pile interaction is linearly idealized as an upright beam on Winkler foundation model which is commonly used to study the response of single piles. A sufficient number of springs on the beam should be used along the length of the piles. The springs near the surface are usually the most important to characterize the response of the piles surrounded by the soil; thus a closer spacing may be used in that region. However, in generally springs are evenly spaced at about half the diameter of the pile. The results of the stochastic analysis with and without the SSI are compared each other while the bridge is under the sway of the spatially varying earthquake ground motion. Specifically, in case of rigid towers and soft soil condition, it is pointed out that the SSI should be significantly taken into account for the design of such bridges.