• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.9
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• pp.1795-1805
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• 2002

A position controller which can achieve a specified dynamic performance irrespective of the different operating position of the pneumatic cylinder is proposed. The position controller developed in this paper is composed of a nonlinear compensator and a disturbance observer. The nonlinear compensator which feeds back position, velocity and acceleration is derived from the nonlinear dominating equations of the position control system to compensate for variation of dynamic characteristics of a pneumatic cylinder according to the change of the operating position. The disturbance observer including a simplified linear model is designed to reduce the effect of model discrepancy in the low frequency range which cannot be suppressed by the nonlinear compensator. The results of the experiments show that the position control performance maintains a designed performance regardless of the variations of an operating position of the pneumatic cylinder.

• PNF and Movement
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• v.14 no.1
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• pp.1-6
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• 2016

Purpose: The purpose of this study was to analyze the effects of proprioceptive neuromuscular facilitation (PNF) patterns on electromyography (EMG) activity in the rectus abdominis, internal abdominal oblique, external abdominal oblique, and erector spinae according to position changes. Methods: Ten healthy adults volunteered to participate in the study. The subjects were required to complete exercises that followed two PNF extremity patterns, namely, an upper extremity extension-adduction-internal rotation pattern and a lower extremity flexion-adduction-external rotation pattern. The exercises were applied in the supine, side-lying, and sitting positions. Repeated measure one-way ANOVA and post-hoc Bonferroni correction were used to determine the influence of the patterns on muscle activity for each muscle, and descriptive statistics were then used to determine the local/global muscle ratios. Results: The upper extremity pattern had a significant effect on the rectus abdominis and erector spinae in the supine position, and on the internal oblique and external oblique in the sitting position (p<0.05). The median value for the internal oblique/rectus abdominis showed a high ratio of 2.05, and a high ratio of 1.01 was shown for the internal oblique/external oblique in the sitting position. The lower extremity pattern had a significant effect on the rectus abdominis in the side-lying position and on the internal oblique, external oblique, and erector spinae in the sitting position (p<0.05). The median value for the internal oblique/rectus abdominis showed a high ratio of 2.83 in the sitting position and a high ratio of 1.30 for the internal oblique/external oblique in the side-lying position. Conclusion: The PNF pattern increases local muscle activation in an unstable position. Therefore, when the pattern is used for intervention purposes, trunk stability and varied position changes should be taken into account.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.504-507
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• 2011

The inertial migration of a two-dimensional elastic capsule in a channel flow was studied over the Reynolds number range $1{\leq}Re{\leq}100$. The lateral migration velocity, slip velocity, and the deformation and inclination angle of the capsule were investigated by varying the lateral position, Reynolds number, capsule-to-channel size ratio(${\lambda}$), membrane stretching coefficient(${\Phi}$), and membrane bending coefficient(${\gamma}$). During the initial transient motion, the lateral migration velocity increased with increasing Re and ${\lambda}$ but decreased with increases in ${\Phi}$, ${\gamma}$ and the lateral distance from the wall. The initial behavior of the capsule was influenced by variation in the initial lateral position ($y_0$), but the equilibrium position of the capsule was not affected by such variation. The balance between the wall effect and the shear gradient effect determined the equilibrium position. As Re increased, the equilibrium position initially shifted closer to the wall and then moved towards the channel center. A peak in the equilibrium position was observed near Re=30 for ${\gamma}=0.1$, and the peak shifted to higher Re as ${\gamma}$ increased. Depending on the lateral migration velocity, the equilibrium position moved toward the centerline for larger ${\gamma}$ but moved toward the wall for larger ${\Phi}$ and ${\gamma}$.

• Physical Therapy Rehabilitation Science
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• v.10 no.4
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• pp.444-449
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• 2021

Objective: The purpose of this study is to observe the change in the thickness of abdominal muscles when electrical muscle stimulation (EMS) is applied to the abdomen during rest and abdominal muscle exercise to investigate the effect of EMS applied to the abdomen on the superficial and deep muscles thickness. Design: Cross sectional design. Methods: Twenty healthy subjects participated in this study. Subjects were performed resting position, resting position with EMS, curl-up and curl-up with EMS. The electrode of the EMS belt is attached to the abdominal wall between the 12th rib and iliac crest. The thickness of abdominal muscles including rectus abdominis (RA), external oblique (EO), internal oblique (IO), and transverse abdominis (TrA) were captured in each position by ultrasound image during expiration. All subjects were performed four positions randomly. Data were analyzed using repeated ANOVA with the level of significance set at 𝛼=0.05. Results: The muscle thickness of RA, EO, IO and TrA were significantly different at each position (p<0.05). The thickness of all abdominal muscles increased significantly when curl-up than curl-up with EMS. Both RA and EO thickness were significantly increased at resting position than resting position and EMS were combined(p<0.05). But IO and TrA thickness were decreased at resting position when EMS were combined. Conclusions: The results suggest that EMS activates superficial abdominal muscles RA and EO. Therefore, abdominal strengthening exercise combined EMS can activate abdominal muscles and can be applied to various patients and rehabilitation in clinical practice.

• Journal of Korean Clinical Nursing Research
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• v.16 no.1
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• pp.5-15
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• 2010

Purpose: The purpose of this study was to examine the effect of position change on the level of comfort and occurrence of bleeding after transarterial chemoembolization. Methods: This study was the nonequivalent control group non-synchronized design. The experimental group was positioned in supine with 15-30 degree Semi-folwer's position for 2 hours and then changed supine position alternatively to 30 degree lateral positioning in turn per hour for 2 hours. For the control group, 6 hour supine positions without any position change were applied. Results: The level of discomfort of the control group was scored higher level than that of the experimental group. There was no significant differences in back pain and the degrees of voiding difficulty. There were no significant differences in the incidence of bleeding complication between the two groups. Conclusion: The position change in patients after transarterial chemoembolization could be applied without any severe side effects such as bleeding complication, but it was revealed to be effective in reducing the level of discomfort.

• Bulletin of the Society of Naval Architects of Korea
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• v.8 no.2
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• pp.35-44
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• 1971

In terms of this paper, concerning primarily with the U-tube tank stabilizer, the authors' aim is to clarify and consolidate the theory as it has been developed thus far, and to provide with the certain additions which will make it more complete, more accurate, and more practical. And then we can know that the effect of the vertical tank position from the C.G., $a_{st}=1-w^2/{w^2}_{st}$, is very important, on account for the fact that the position factor, $a_{st}$, increase when the anti-rolling tank attaches to higher position vertically, but $a_{st}$ does not increase in proportion to the distance of the tank position. Measuring many characteristic coefficients by experiment, in the equation of the ship-tank system motion, such as the inertia coefficient, the damping coefficient, the natural frequency and so on, they can also give a guess that the higher position will accompany the non-linear motion of the tank water, but the non-linear effect will decrease the tank ability. In this study, they deal with not only the optimum damping coefficient of tank, which has very simply been expressed by the strength ratio, $\lambda$, but also the effect of the tank top, which has experimentally been treated when the water has hit the tank top. As this result, we can immediately find that the ability of the anti-rolling tank decrease at w/ws=0.9 generally low frequency.

• Journal of Power Electronics
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• v.8 no.3
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• pp.268-274
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• 2008

This paper presents a proposed position controller for a vector controlled induction motor. The position controller design depends on the rotational motion equations and a classical speed controller (CSC) performance. The CSC is designed to have the ability to track variable reference inputs and to provide a predefined system performance. Standard position controller in industry is presented to analyze its performance and its drawbacks. Then the proposed position controller is designed, based on the well defined rotational motion equations. The proposed position controller and the CSC are applied to control the position and speed of the vector controlled induction motor with different ratings. Simulation results at different operating conditions are presented to evaluate the proposed controllers' performance. The results show that the CSC can drive the motor with a predefined speed performance and can track a variable reference speed with an approximately zero steady state error. The results also show that the proposed position controller has the ability to effect high-precision positioning in a limited time and to track a variable reference position with a zero steady state error.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.149-154
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• 2002

In a high speed spindle system, it is very important to monitor the state of rotating rotor. Particularly in active control spindle system, the position sensor must provide feedback to the control system on the exact position of the rotor. In order to monitor the state of a high speed spindle exactly, high accuracy and wide frequency bandwidth of sensors are important. This paper observes the factors which has an effect on dynamic performances of inductive position sensor.

• Journal of Preventive Medicine and Public Health
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• v.19 no.1 s.19
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• pp.123-129
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• 1986

Fetal weight data from 84 litters of Sprague-Dawley rats were statistically analyzed for the effect of position in the uterine horn on fetal weight. The standard score obtained from the mean weight and standard deviation of all fetuses in a uterine horn were studied for position effect. In control group, the heaviest fetus occupied the middle position with a progressive decrease in weights toward the ovarian and cervical ends of the horn. But the effect related to position for the fetal weight was not statistically significant. In contrast, rats acutely or chronically exposed to carbon monoxide showed statistically significant positional differences of fetal weight within the uterine horns. The findings that the intrauterine position effect on fetal weight which is not signicant in control group may act one of confounders at the situation of transplacental toxicological studios.

• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.271-280
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• 2020

Purpose : The purpose of this study examines the mediating effect of women leader's characteristics in the relationship between clan culture and market culture of global companies. In addition, this study attempts to analysis the mediating effect of women leader's position and carrier in the relationship among facilitator, mentor, producer, and director leadership using partial mediation and completed mediation model. Research design, data, methodology : Conceptual research model is designed with three constructs such as clan culture, woemn leader's characteristics, and market culture. Based on five hundred cases with leadership styles and organizational culture of global companies, this study examine the mediating effect of women leader's characteristics in the relationship between clan culture and market culture using structured equation modeling. Results : Facilitator leadership have a significantly positive influence on women leader's position and carrier. Mentor leadership have a significantly positive influence on women leader's carrier while they are not correlated with mentor leadership and women leader's position. Women leader's position and carrier have a significantly positive influence on director leadership while women leader's position and carrier not have a positive influence on procucer leadership. Also facilitator and mentor leadership have a significantly positive on producer and director leadership. Conclusions : By controlling for the mediating effect of women leader's characteristics, this study have improved the academic contributions as well as policy and practical implications through empirical study of clan culture that affect market culture in the filds of leadership style and organizational. In addition, this study means that the mediating effects on the variables of women leader's position and carrier were examined.