• Korean Journal of Applied Biomechanics
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• v.21 no.3
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• pp.353-359
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• 2011

The purpose of this study was to investigate the effects of exercise-induced fatigue and blocked vision on postural control during upright stance in elderly women. The study population included 22 women who were aged over 65 years, had no sustained orthopedic damage within the last 6 months, and had been randomly recruited. The results were analyzed with respect to the mediolateral and anteroposterior factors for the center of pressure. The exercise-induced fatigue and the absence of visual information increased the anteroposterior and mediolateral velocity for center of pressure. This means that the elderly women could control their posture through many sways. In conclusion, the exercise-induced fatigue and the blocked vision decreased ability of the postural control in elderly women. Further research on the change of postural control in relation to the types of exercise-induced fatigue and the levels of muscular fatigue is expected.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.5
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• pp.837-844
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• 2013

This study performs erection of a pendulum hanging at a free end of an arm by rotating the arm to the upright position. A mathematical model of a rotary inverted pendulum system (RIPS) is derived. A brain emotional learning based intelligent controller (BELBIC) is designed and used as a controller for swinging up and balancing the pendulum of the RIPS. In simulations performed in the study, a pendulum is initially inclined at $45^{\circ}$ with respect to the upright position. A simulation is also performed for evaluating the adaptiveness of the designed BELBIC in the case of system variation. In addition, a simulation is performed for evaluating the robustness of the designed BELBIC against a disturbance in the control input.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2240-2242
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• 2001

A rotary double inverted pendulum, the nonlinear system has a regulation problem. In this paper, we linearize the nonlinear system at the upright equilibrium position. The linearized system can be expressed in state space. To maintain the upright position, we design a feedback controller using LQR(Linear Quadratic Regulator) algorithm. Then we simulate the system with third-order Adams Bashforth Moulton Method. The simulated result shows that the applied algorithm is effective for the regulation problem.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1724-1726
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• 2000

We have investigated a molecular orientation effect of septithiophene(7T), the conjugated linear septenary of thiophene, on its optical and electrical properties. Vacuum evaporation of septithiophene on a substrate induces a upright orientation. We rubbed the pre-layer to lie down molecules. As a result, we could get a horizontal molecular orientation. Dichroic ratio is about 2 at 418nm from UV/visible absorption spectrum. To investigate the electrical characteristics, we fabricated devices with septithiophene as a semiconducting material. The conductivity with horizontal septithiophene orientation is about one order gloater than that of upright septithiophene.

• Journal of the Korean Institute of Intelligent Systems
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• v.25 no.6
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• pp.578-584
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• 2015

In this study a moving platform for a mobile robot that can be traveling with a full automatic standing arm was developed. Conventional mobile robots generally may equip 4 wheels or 3 wheels with a caster wheel or independent driven wheels and have good statistic stability. When a mobile robot travels on a sharply perpendicular and narrow crossroad, it may need a special steering scheme such as going forward and backward repeatedly or it is sometimes physically impossible for the robot to go through the crossroad because of the size limit. The upright running mobile robot changes its posture to the upright posture which has a small planar area and is able to go through the crossroad. The upright control which was manually performed step by step before such as sequences of uprighting (returning), checking, and balancing, is now automated.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.579-582
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• 2009

This paper reports the electrical characteristics of polyvinylpyrrolidone (PVPy) and the performance of organic thin-film transistors with PVPy as a gate insulator. PVPy shows a dielectric constant of about 3 and contributes to the upright growth of pentacene molecules with 15.3${\AA}$ interplanar spacing. These results will be discussed.

• Journal of the Ergonomics Society of Korea
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• v.15 no.1
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• pp.53-67
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• 1996

Since Romberg's test in 1953, the analysis of postural sway during upright stance has been widely used as a tool for evaluating balance and disorders of the postural control system. This review describes the methods that have been used to evaluste the static and dynamic performance of the postural control system. Various identification methods of postural control system based on standing balance are discussed and measures of postural sway are described. The application areas of standign balance research, with an emphasis on postural control evaluations, are also briefly described. This review can be used to gain an understanding of the dynamics of human standing balance.

• Korean Journal of Plant Resources
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• v.10 no.2
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• pp.140-144
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• 1997

This experiment was carried out to investigate the proper planting method of Rehmannia glutinasa Liboschitz. A Chungbuk local cultivar was sown on the seed bed of 200cm with the planting density of 30cm(6 rows) $\times$ 8.5cm(30 rhizome per $\textrm{m}^2$). The experimental design was randomized block design with 3 replications. And the result was summarized as follows. The emergence date of level Planting(control : 0$^{\circ}$) was May 23, but the emergence dates of Oblique planting(45$^{\circ}$) and Upright planting(90$^{\circ}$) treatments were later than the control by 2~4 days. And the leaf length and the ratio of leaf length/leaf width were not significantly different. As compared with the 29.2cm and 10.0mm of the rhizome length and the rhizome diameter of level planting treatment, the rhizome length of Oblique planting treatment was decreased by 3.4cm and 0 mm. The length and diameter of rhizome of the Upright planting treatment was decreased by 2.8cm and 1.0mm. And the order of sugar content was level Planting > Oblique planting > Upright planting. The total yields were decreased by 9% in the Oblique planting and by 15% in the Upright planting compared to 1,203kg/10a in the control, and the commercial yields showed the same tendency. The level planting treatment was found to be most proper for sowing of Rehmannia glutinasa Liboschitz in the middle inland region of Korea.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.2
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• pp.171-176
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• 2013

In this research a Self-Standable mobile Robot with standing arms based on an Wheeled Inverted Pendulum is developed. Almost existing mobile robots have wide planar shape that is statistically stable and it is sometimes hard for them to run or steer on a narrow road. A Wheeled Inverted Pendulum based mobile robot has vertical shape that is upright-running and easily steering on a narrow road. It, however, requires actively balancing control and never restores the shape once it falls down. This research develops a Self-Standable mobile robot which equips standing arms and is able to change its chassis' posture freely from planar to vertical shape or vice versa.

• The Journal of Korean Physical Therapy
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• v.35 no.5
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• pp.156-161
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• 2023

Purpose: This study examined the effects of subjective visual vertical perception and head orientation on static balance control. Methods: The subjects were 25 young and healthy adults. The vertical perception was measured using a subjective visual vertical (SVV), and the Center of pressure (COP) parameter was analyzed by continuously measuring the movement of the COP to determine the changes in static postural control. The group was divided based on a deviation of 3° in SVV (11 of SVV≥3°, 14 of SVV<3°) and measured with different head orientations: front, up, down, left, and right in the upright and tandem positions, respectively. Results: In the upright position, the SVV≥3° group had significantly larger values for all COP parameters (Sway length, Surface, Delta X, Delta Y, and Average speed) compared to the SVV<3° group (p<0.05). In the tandem stance, only the Ellipse Surface value was significantly larger among the COP parameters in the group with SVV≥3° compared to the group with SVV<3°(p<0.05). In contrast, the other COP parameters were not significantly different (p>0.05). The effects of static balance control on the head orientation were not statistically significant (p>0.05), and the interactions between the subjective vertical perception and head orientation were not significant (p>0.05). Conclusion: These results suggest that pathological deviations in SVV are associated with impaired static balance performance. This study can provide a therapeutic rationale for using visuospatial cognitive feedback training to improve the static balance.