• Journal of Biomedical Engineering Research
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• v.32 no.3
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• pp.191-197
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• 2011

Lifting chair is a typical assistive product to aid for standing up and sitting down for persons with disability. It is particularly useful for the elderly persons whose muscular system is weakened by degenerative joint disease. This paper describes biomechanical assessments of lifting chair with hip-up function. In experiments we measured 3D motion and electromyographic(EMG) signal on the femoral muscle when subject performs the standing motion on the predetermined seat height. Based on assessment of the standing motion, we select the hip-up angle as 15 degrees to cover the relative femoral angle when EMG peak value is appeared. Using an implemented prototype lifting chair with hip-up function we perform standing experiments with five subjects. The experimental results show that the lifting and hip-up functions are effective to assist for standing up motion with less muscle force.

• The Journal of Korean Physical Therapy
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• v.27 no.5
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• pp.320-324
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• 2015

Purpose: The purpose of this study was to provide methods for assessment of functional balance through study of correlation with the weight bearing ratio, functional balance, and functional gait on patients with stroke. Methods: Thirty-nine patients with stroke participated in this study. The timed up and go test was used to measure balance and the functional ambulation category test to measure functional gait. Weight bearing was measured in the quiet standing posture and weight bearing in the quiet standing posture immediately after performing the standing-task. Results: Both timed up and go test and functional ambulation category test showed significant correlation with balance in the quiet standing posture immediately after performing the standing task. Conclusion: Measurement of balance in the quiet standing posture immediately after performing the standing-task was considered a meaningful scale for measurement of both balance function and gait function of patients with stroke.

• Physical Therapy Korea
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• v.24 no.1
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• pp.97-104
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• 2017

Background: South Korea is one of fastest aging countries in the world. Poor balance and falls of the elderly are main health issues. Objects: The goal of this study was to understand the association between the socioeconomical factors and the standing balance of elderly living in the rural and urban area. Methods: One hundred sixty-six elderly participants who were older than 65 and were able to walk without an assistive device were recruited in the city of Gwangju and in the rural area of Jeonnam, South Korea. All participants performed the static and dynamic standing balance tests. Static standing balance was measured with chronometer in seconds while standing on one leg. Dynamic balance was tested with the timed up and go test (TUG), measured in seconds while getting up from a chair and walking 3 meters and back to sit. The static and dynamic standing balance was analyzed using analysis of variance and the Fisher's Least Significant Difference post hoc test. Results: Male participants from both areas had no difference in one leg standing and TUG. The female elderly living in rural area took shorter in TUG than females living in urban area. Age decreased the one leg standing time in both areas while did not affect the TUG significantly. As the monthly income increased, both of one leg standing and TUG increased in urban area, while the medium monthly income showed best performance (it was not statistically significant) in both of one leg standing and TUG in rural area. Conclusion: Socioeconomical factors affects differently the standing balance of the elderly living in rural and urban South Korea. Female living alone in urban area with low monthly income demonstrated worst standing balance in this study.

• Journal of the Ergonomics Society of Korea
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• v.33 no.4
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• pp.281-287
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• 2014

Objective: The objective of the study is to develop a portable assistance device to help elderly users reduce strain on the knee and leg muscle while the elderly are standing up. Background: The pose of standing up from a chair is a basic movement, but the elderly often have difficulty standing up due to their weak muscles. We focus on designing a solution that helps the elderly reduce physical problems and support them standing up. Method: This study consists of three parts. Part I explores the way to reduce the refrain of leg muscle while standing up from a chair. In the process of structural development, we found that the moment is minimized when user pushes down the armrests due to a decrease in the force acting on the center of mass. In part II, a user test of 20 participants was carried out to rank the order of comfort of two stimuli: the chair with fixed armrests and the chair with the four-link mechanism that we created-in three different ways; (1) to stand up without touching armrests, (2) to stand up by pushing down on fixed armrests, and (3) to stand up by pushing down on armrests and being supported by the mechanism. To examine the statistically significant differences among the rank means, a Friedman test was conducted. In part III, we analyze the results of the user test and interview feedbacks, focusing on establishing a design strategy from UPO and visualizing it in 1:1 scale. Results: In part I, we decided to develop the four-link mechanism. The bottom is lifted up as the link rises. In part II, based on the rank data, we empirically found that UPO was assessed as the most comfortable during the stimuli. The thigh angle is smaller and the bottom of UPO is separated from a seat. In part III, after assessing the results and feedbacks, we created a visualization strategy for UPO: light, friendly, and novel. Conclusion: The portable and non-mechanical UPO comprises a four-link system that lifts the user's hips while standing. It can help users avoid knee and leg muscle strain. Its universal design considers the elderly's difficulties. Application: In a future study, combining light and durable material in UPO is expected to increase its usability. And this study is an opportunity to design various types of standing assistance devices.

• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.169-173
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• 1992

The surface geometry of o-diiodobenzene (ODIB) adsorbed on silver colloid surfaces has been studied. This molecule is standing up on 1 day old colloid surfaces, while it is lying down or standing up on 1 month old colloid surfaces. The surface geometry of ODIB is affected by the atomic scale surface roughness of colloid used. The SERS intensity of ODIB for lying down geometry is much more strong than that for standing up. This may be mainly due to that the distance from surface to the center of the molecule in lying down geometry is shorter than that in standing up.

• Journal of the Ergonomics Society of Korea
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• v.35 no.6
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• pp.493-501
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• 2016

Objective: This study analyzes the effect of angle conditions of rehabilitation equipment used for supporting hemiplegic patients on their rehabilitation training for standing action. The study was performed by adjusting the rear angle of seat inclination through a motion analysis. Background: Owing to a loss of muscle rigidity and degradation of muscle control ability, hemiplegic stroke patients suffer from asymmetrical posture, abnormal body balance, and degraded balance abilities due to poor weight-shifting capacity. The ability to shift and maintain one's weight is extremely essential for mobility, which plays an important role in our daily life. Thus, to improve patients' ability to maintain weight evenly and move normally, they need to undergo orthostatic and ambulatory training. Method: Using a motion analysis system, knee movements on both hemiplegic side and non-hemiplegic side were measured and analyzed in five angles ($0^{\circ}$, $10^{\circ}$, $30^{\circ}$, $50^{\circ}$, $70^{\circ}$) while supported by the sit-to-stand rehabilitation equipment. Results: The knee movements on both sides increased as the angle increased in angle support interval to support a hemiplegic patient's standing up position. In standing up interval, a hemiplegic patient's knee movement deviations on both sides decreased, and the movement differences between hemiplegic and non-hemiplegic legs also decreased as the angle increased. Conclusion: The results of this study showed that the rehabilitation effectiveness increases as the angle increases, leading to a balanced standing posture through the decrease of movement difference between hemiplegic and non-hemiplegic sides and an improved standing up ability through the increase of knee movement on both sides. However, angles higher than $50^{\circ}$ didn't provide a significant effect. Therefore, a support angle under $50^{\circ}$ was proposed in this study. Application: The results of this study are expected to be applicable to the design of sit-to-stand support equipment to improve the effectiveness of the rehabilitation process of hemiplegic patients.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.3
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• pp.108-114
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• 2018

One of the most performed action in daily life is standing up from sitting position. As the population of the world is aging at the high rates, people may face problems with reduced muscle strength as well as psychological changes. This can lead elderly people having difficulties with standing up from chair. Now, with the aging trend worldwide, products are being developed that can support the lives of the elderly. This study examines the distribution of hip pressure in relation to the seating positions of the standing assistance seats under development to prevent standing up accidents in older adults. The currently developing standing assistant chair designed to tilt to a maximum angle of 25 degrees. At over $25^{\circ}$, design considers that older people are at risk of thrown back out of that force and that the forces exerted on their arms and legs can be a significant burden to older people. By considering danger of higher than $25^{\circ}$ for older people which is experimented in the basis of static capturing approach in previous papers, it is experimented people with age group of 20~60 on $0^{\circ}$ to $25^{\circ}$ tilting angle on the basis of dynamic capturing method in order to pick convenient angle of inclination. Moreover, tried to find the optimum angle by comparing the hip pressure distribution when seated at the edge of the seat and at the center of the seat with the pressure distribution sensor.

• Journal of Korean Academy of Nursing
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• v.19 no.3
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• pp.285-298
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• 1989

This study investigated the effect of changing position from supine to standing upright on the circulation of young men and women. Healthy men and women ranging from age of 18 to 24 were examined. Two minutes before standing, the baseline heart rate and blood pressure were measured. Heart rate and blood pressure were recorded immediately and at every minute for 10 minutes after standing upright. Differences in heart rate and blood pressure between supine and standing upright position were evaluated. The results were summarized as follows : 1. Heart rate increased significantly immediately and at every minute for 10 minutes after standing upright. 2. Systolic blood pressure increased significantly immediately and at every minute for 4 minutes after standing upright. 3. Diastolic and mean blood pressure increased significantly immediately and at every minute for 10 minutes after standing upright. 4. Pulse pressure immediately and at every minute for 10 minutes after standing upright was significantly narrower than that of supine position. 5. There was no significant difference of heart rate between men and women after standing upright. 6. Systolic and diastolic blood pressure of men after standing upright was significantly greater than those of women. From these results, it may be concluded that heart rate, systolic, diastolic and mean blood pressure and pulse pressure increase after standing upright, and systolic and diastolic blood pressure in men is greater than those of women after standing upright.

• Physical Therapy Rehabilitation Science
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• v.11 no.4
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• pp.591-597
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• 2022

Objective: The sitting and standing are motions that correspond to the previous stage of rehabilitation to go to walking for daily life. The purpose of this study was to measure task times, path length of the center of pressure (COP) and activity on the vastus femoris muscle using surface electromyography (EMG) when standing up and sitting down. Design: One group cross-sectional design Methods: Fifteen elderly subjects (8 male, 7 female) participated. All subjects were tested three times according to four assist levels (non-assist, lower, middle, and maximal assist) using adjusts the length of spring at sit-to-stand and stand to sit on a chair. The task duration, and COP path length were recorded for the balance function on the Nintendo Wii fit board. The activity of the rectus femoris muscle was recorded on both legs using surface EMG. Results: The results showed that the task duration of the sit-to-stand and stand-to-sit were significantly increased compared to without assist (p<.05). The activation of the rectus femoris muscle more significantly decreased compared to without assistance at standing or sitting (p<.05). Conclusions: The assistive chair showed less quadriceps muscle activation during sitting and standing compared to without assistance. We suggest that our assist-standing chair can help with activities of daily living such as standing up and sitting down movements adjusting the spring length for control assist level by safely.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.89.5-89
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• 2001

In this paper we explain about systems developed to forecast the standing up of the dementia patients. Basic idea of our approach is to measure the respiration and body movements in the bed. Based on the data measured, forecasting of standing up action from the bed is possible to some extent. First system proposed uses an image processing technique. Data obtained about the respiration and movements are used to forecast the standing up of the patients. The second system uses ultrasonic sensors, which emits and receives ultrasonic signals. Two techniques f the ultrasonic sensors are considered. One technique is to emit ultrasonic burst signals and to detect the instance when ...