• Physical Therapy Korea
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• v.19 no.3
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• pp.40-50
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• 2012

The purpose of this study was to investigate the effect of visual feedback on the postural control of stroke patients, by systematically varying conditions of visual feedback [eye-open condition (EO) vs. eye-closed condition (EC)], and base-support (both-side support, affected-side support, and unaffected-side support). In this study, we allocated 41 stroke patients with no damage in the cerebellum and visual cortex who can walk at least 10 meters independently, and 35 normal adults who have no experience of stroke to the control group. Both groups were asked to perform a "sit-to-stand" task three to five times, and their postural control ability was measured and compared in terms of asymmetric dependence (AD) instead of the traditional symmetric index (SI) in the literature. The results showed that although both subject groups maintained better postural control in the EO condition than in the EC condition, the patient group appeared to be more stable in EC than in EO when they were required to perform the task of the support condition given on the affected side. These results implied that visual feedback can impair stroke patients' postural control when it is combined with a specific support condition.

• The Journal of Korean Physical Therapy
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• v.30 no.2
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• pp.41-46
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• 2018

Purpose: This study examined the effects of knee extension exercise using blood flow restriction on the changes in the thickness and static balance ability of the tendon of the rectus femoris muscle and achilles tendon. Methods: A total of 30 subjects was were divided into two groups of 15 subjects each. The changes in the thickness and balance of their tendons were measured by ultrasonography and balance equipment. The measurements were taken three times: before the experiment, 4 weeks after, and 8 weeks after. The results were analyzed by repeated measure ANOVA, one-way ANOVA was conducted in cases where there were time-to-group interactions in the intra-individual effects test. Results: Significant differences in the thickness of the tendon of the rectus femoris muscle and Achilles tendon were found between the groups, over time, and in the time-to-group interactions (p<0.05). The changes in balance in both feet when the supporting positions between eye-open and eye-closed states were significantly different in the time-to-group interactions (p<0.05), but were not different between the groups (p>0.05). Conclusion: Knee extension exercise using blood flow restriction leads to significant differences in the increase in tendon thickness and changes in balance, indicating that the results of this study can be utilized as basic data for future studies and for rehabilitation treatment at clinics.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.6
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• pp.177-186
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• 2005

This paper introduces nonlinear estimators with reduced complexity, and proposes the Bussgang blind equalization algorithm employing the nonlinear estimators. The proposed algorithm utilized the facts that the Bayesian estimator is well approximated to the sigmoid estimator in initial stage of equalization with closed eye and is well approximated to the threshold estimator under open eye condition. The proposed method adopts selectively one of the two nonlinear estimators, i.e., the sigmoid estimator and the threshold estimator, according to channel distortion level at each iteration. As a result, by using the sigmoid estimator with reduced constellation, the proposed scheme, as it is applied to blind equalization of high-order QAM signals, simplifies the computational complexity extremely, and enhances the blind convergence capability and steady-state performance.

• The Journal of Korean Physical Therapy
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• v.19 no.6
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• pp.11-15
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• 2007

Purpose: This study examined the various patterns of standing to squatting activities, and reports the testing standard and phases for examining the standing to squatting position. Methods: One thousand, normal college students (500 males, 500 females) volunteered for this study. The patterns are performed by naked eye analysis with two video cameras. Results: The patterns from the standing to squatting position are as follows 1. parallel with the heel on the pattern: 2. parallel with the heel off the pattern: 3. closed with the heel on the pattern: 4. closed with the heel on the pattern: 5. open with the heel on the patternand 6. open with the heel on the pattern. Conclusion: The phases of the standing to squatting position are as follows: phase I from standing to the anterior parts of the knees reaching the anterior limit of the BOS, phase II from phase I until the height of the hip and knee joints are the same, phase III from phase II until there was no full squatting and the heels broke contact with the floor and phase IV from phase III full squatting on the heels in contact with the floor.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.266-277
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• 1995

The adult brown planthopper possesses tow oval shaped compound eyes which, on their ventral borders, curve around the base of the antennae. Compound eye of the adult brown planthopper is recognised apposition eye which each ommatidium is optically isolated from it surroundings, the rhabdoms receiving light only from their own corneal lens. Each ommatidium possesses its own dioptric apparatus formed from the cuticular cornea and an underlying crystalline cone. The retinula cells lying immediately beneath the crystalline cone have their individual rhabdomeres tightly opposed to form one central, closed rhbdom. The rhabdom stretches from the spex of the crystalline cone nearly to the basement membrane and is approximately 110~120 $\mu\textrm{m}$ in length. The crystalline cone is surrounded by a pair of primary pigment cells an these in turn are surrounded by accessory pigment cells. Accessory pigment cells extend beyond the crystalline cone surrounding the retinular cells in the distal region of the eye. The crystalline cone is surrounded by the distal-most regions of the retinula cells show the presence of seven cells and sections taken proximally in the last quarter of the omatidium before the basement membrane is reached, reveal the presence of a small, eighth retinula cell which also contributes to the central rhabdom. Each ommatidium has a central rhabdom formed from the modified inner border of all of the retinula cells. Th rhabdom consists of micrvilli arising from the inner wall of each retinula cell. In cross section th microvilli exhibit a characteristic honeycomb appearance. Pigment cells comprise the primary pigment cells enveloping the crystalline cone, the accessory pigment cells extending from the inner surface of the comea to the basement membrane and the small pigment cells of the basement membrane.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.10
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• pp.1047-1052
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• 2008

In this paper, we design an image-based robust controller to compensate uncertainties with image Jacobian and robot dynamics due to uncertain depth measurement and load variations. The proposed controller with eye-in-hand structure has separate terms to compensate each of uncertainties. The ultimate boundedness of the closed-loop system is proved by the Lyapunov approach. The performance of the proposed control system is demonstrated by simulation and experimental results a 5-link robot manipulator with two degree of freedom.

• The Journal of Korean Medicine
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• v.24 no.4
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• pp.136-138
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• 2003

Purpose : A clinical case of diabetic foot-wound repair using Hirudo medicinalis therapy and its application is reported and discussed. Methods : The subject was a sixty-six-year-old woman diagnosed with a non-healing wound indicating the amputation of her right diabetic foot. Instead, Hirudo medicinalis therapy was performed twelve times over forty days, twice a week. The transition of wound closure was observed with the naked eye, and the plethysmogram was measured at the beginning and end of the treatment period. Results : The wound contracted with decreased exudate, collagen-like connective tissue sprouted, and then the wound gradually closed. The initial value (-0.08) of the dicrotic elastic index rose to -0.03. Conclusion : Hirudo medicinalis therapy had a positive effect on the wound repair, without a negative effect on the circulation, allowing the foot to be saved. It is necessary to investigate its wound repair mechanism for the further development of the Sahyul method.

• Journal of the Korean Society of Physical Medicine
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• v.7 no.2
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• pp.191-197
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• 2012

Purpose : The purpose of this study was to examine immediate effects of 15 minutes plantarflexor static stretching in quite stance. Methods : Twenty-nine subjects were measured static balance during 1 minute in quite stance with eye closed condition before and after 15 minutes plantarflexor static stretching. Static stretching range was limited from $15^{\circ}$ to $20^{\circ}$ dorsiflexion within comfortable range. Results : The result of this study showed that postural sway significantly increased during 1 minute quiet stance after 15 minutes static stretching(p<.05). Before stretching, postural sway significantly decreased during 41-60 seconds compared to 0-20, 21-40 seconds(p<.05). After stretching, postural sway was decreased significantly over time 0-20, 21-40, and 41-60 seconds(p<.05). Conclusion : The prolong plantarflexor static stretching may require biomechanical, neurological adaptations prior to walking or sport activities for safety.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.211-212
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• 1998

In this experiment, we developed a mind switching device which uses $\alpha$-wave with its amplitude varying between the eye-open and closed states. If the subject closes eyes, the switch toggles with a small delay. The circuit consists of an amplifier, a filter and a switch. An instrument amplifier is used fur high CMRR and for high input impedance. An 8th order Butterworth filter was able to reduce noise satisfactorily. The signal is then converted to a DC level, and finally a Schmitt trigger was used to generate a switching pulse.

• Journal of Korean Physical Therapy Science
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• v.18 no.4
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• pp.59-64
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• 2011

Purpose : The purpose of this study was to evaluate the effects of the stretching of the calf muscles on foot pressure and contact area in young adult. Participants stood on a wedge board that was sloped between 15~25 degree for 15min. After stretching participants stood quietly on force plate, result was recorded. Participants stood on a force plate for 1 min in eye closed condition, and them the foot pressure and area was recorded. The following variables were calculated off-line: anterior and posterior foot pressure and contact area, medial and lateral foot pressure and contact area. Results showed that anterior pressure change due to stretch, but mediolateral was not significant. This result suggested that stretching of the calf muscle has the effect of increasing anterior pressure by flexibility change on calf muscle, so this effects might be effective intervention for reduce of serious problem to neurologic patients in therapy session.