• Journal of Korean Society of Coastal and Ocean Engineers
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• v.2 no.4
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• pp.208-222
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• 1990

The nonlinear hydrodynamic pressure force and moment on hinged wavemakers of variable-draft are presented. A closed-form solution (correct to second-order) for the nonlinear wavemaker boundary value problem has been obtained by employing the Stokes perturbation expansion scheme. The physical significance of the second-order contributions to the hydrodynamic pressure moment are examined in detail. Design curves are presented which demonstrate both the magnitude of the second-order nonlinearities and the effects of the variable-draft hinge height. The second-order contributions to the total hydrodynamic force and moment consist of a time-dependent and a steady part. The sum of the first and second-order pressure force and moment show a significant increase over those predicted by linear wavemaker theory. The second-order effects are shown to vary with both relative water depth and wave amplitude. The second-order dynamic effects are relatively more important for hinged wavemakers with shallower drafts.

• Journal of The Korean Society of Integrative Medicine
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• v.3 no.4
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• pp.69-78
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• 2015

Purpose: The purpose of this study was to identify whether inclined treadmill gait training with rhythmic auditory simulation (RAS) could improve on balance and gait in stroke patients. Method: Fifteen stroke patients who had agreed with the study were allocated to the group 1(n=5), group 2(n=5), or group 3(n=5). The group 1, group 2 and group 3 performed RAS with inclined treadmill gait training, inclined treadmill gait training and treadmill without incline gait training respectively for 3 weeks (30 minutes per session, 5 times in a week). The balance was assessed using Timed Up & Go (TUG) and Berg Balance Sale (BBS), and the gait was evaluated using 6 Minutes Walking Test (6MWT) and spatio-temporal walking variables as walking speed, cadence, Single Limb Support of affected side(SLS) and Symmetric Index(SI) before and after training. Result: Both the group 1 and group 2 showed significant improvement after training in all variables of balance and gait. The group 3 showed significant improvement in TUG values, 6MWT values, walking speed, cadence and SI. The changes in the group 1 were significantly greater in all dependent variables of balance and gait than those of the group 2 and group 3. The changes in the group 2 were significantly greater in TUG values, BBS scores, 6MWT values, walking speed, and cadence than those of the group 3. Conclusion: The result of this study show inclined treadmill gait training with RAS is more effective to improve balance and gait in stoke patients than inclined treadmill or general treadmill gait training without RAS.

• Physical Therapy Korea
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• v.16 no.2
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• pp.1-8
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• 2009

Anticipatory postural adjustments is an example of the ability of the central nervous system to predict the consequence of the mechanical effect of movement on posture and helps minimize a forth coming disturbance. The aim of this study was to evaluate the sequence of activation of the trunk muscles during the performance of hip and shoulder movement and to determine the relationship between anticipatory activity and subjects' motor and functional status in subjects with hemiplegia post stroke. Twenty-four poststroke hemiparetic patients enrolled in this study. Electromyographic activity of the lumbar erector spinae, latissimus dorsi, and of the obliquus internus muscles was recorded bilaterally during flexion of both arm and from the rectus abdominis, obliquus externus, and obliquus internus muscles during flexion of both hip. Onset latencies of trunk muscles were partially delayed in the subjects with hemiplegia post stroke (p<.05). With upper limb flexion, the onset of erector spinae muscle and latissimus dorsi muscle activity preceded the onset of deltoid on both side respectively (p<.05). A similar sequence of activation occurred with lower limb flexion. Also the onset of external oblique muscle and rectus abdominis muscle activity preceded the onset of rectus femoris muscle on both side (p<.05). Major impairments in the activity of trunk muscles in hemiparetic subjects were manifested in delayed onset between activation of pertinent muscular pairs. These problems were associated with motor and functional deficits and warrant specific consideration during physical rehabilitation of post stroke hemiparetic patients.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.4
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• pp.661-674
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• 2002

The objective of this study is to develop efficient numerical method to enable solution of optimal control problems of Navier-Stokes flows and to apply these technique to the problem of viscous drag minimization on a bluff body by controlling boundary velocities on the surface of the body. In addition to the industrial importance of the drag reduction problem, it serves as a model for other more complex flow optimization settings, and allows us to study, modify, and improve the behavior of the optimal control methods proposed here. The control is affected by the suction or injection of fluid on portions of the boundary, and the objective function represents the rate at which energy is dissipated in the fluid. This study shows how reduced Hessian successive quadratic programming method, which avoid converging the flow equations at each iteration, can be tailored to these problems.

• Korean Journal of Applied Biomechanics
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• v.20 no.2
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• pp.139-148
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• 2010

The purpose of this study was to comparatively analyze the kinematic variables between the squash backhand and racquetball backhand strokes through three-dimensional cinematography. Three expert racquetball players and three expert squash players were involved in the data gathering process. The horizontal, vertical and lateral displacement of racket and trunk segment, intersegmental angular velocity of the wrist, elbow and shoulder joints, and the linear velocity of the racket were descriptively analyzed, and the followings were concluded. The racket of the squash backhand stroke showed an 'U' shaped movement where the racket moved rapidly downward and moved forward to make an impact and followed through to a front-top finish, while the racket of racquetball backhand stroke showed an 'O' shaped movement where the racket showed circular movement through the rear and bottom positions for the impact, and showed rotation through the lower-front and upper front to a upper-rear-ward finish during the follow-through. The peak velocity of racket was found before the impact point in the squash backhand stroke and at the impact point in the racquetball backhand stroke. For the final conclusion, for the squash backhand stoke, instructors might be better to make the racket move downward to make highest velocity before the impact and finished short follow-through, while for the racquetball backhand stroke, to make the racket move forward to make highest velocity at the impact and finished rather long follow-through.

• Journal of agricultural medicine and community health
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• v.23 no.1
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• pp.51-64
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• 1998

This study was carried out during 3 years from March 1992 to March 1995, 140 healthy people and 140 C.V.A patients were investigated, at an oriental clinic in Taejon. The data collected was analysed using a SAS. The results are as follows. 1. The Relationships between patients who have undergone one or more abortion procedures and C.V.A occurrence. A statistical significant difference was recorded between the control group and the outpatients group of P<0.05 2. Number of years after initial C.V.A diagnosis before C.V.A symptom onset. within 1 years 52% (2-3 years, 3-4 years, 4-5 years, 5 years and over) 3. Additional diseases occurring after initial stroke 1 disease 50.7% (2, 3, 4, 5 or more) 4. Alcohol Consumption "A statistical significant difference was recorded between the control group and the outpatients group of" P<0.01 5. Previous Treatment Experience for stoke outpatients Oriental Hospital, clinic 64.3% (General Hospital, clinic, a public health center drug store, home remedies, etc) 6. Exercise Frequency Outpatients Regular 28.6%, Irregular 71.4% Control sample Regular 27%, Irregular 72.9% 7. Degree of Appetite "A statistical significant difference was recorded between the control group and the outpatients group of" P<0.01 8. People who include fish in their diet "A statistical difference was recorded between the control group and the outpatients group of" P<0.01.

• Physical Therapy Rehabilitation Science
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• v.7 no.1
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• pp.29-34
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• 2018

Objective: This study aimed to predict balance and gait abilities with the Trunk Impairment scales (TIS) in persons with stroke. Design: Cross-sectional study. Methods: Sixty-eight participants with stoke were assessed with the TIS, Berg Balance scale (BBS), and Functional Gait Assessment (FGA) by a therapist. To describe of general characteristics, we used descriptive and frequency analyses, and the TIS was used as a predictive variable to determine the BBS. In the simple regression analysis, the TIS was used as a predictive variable for the BBS and FGA, and the TIS and BBS were used as predictive variables to determine the FGA in multiple regression analysis. Results: In the group with a BBS score of >45 for regression equation for predicting BBS score using TIS score, the coefficient of determination ($R^2$) was 0.234, and the $R^2$ was 0.500 in the group with a BBS score of ${\leq}45$. In the group with an FGA score >15 for regression equation for predicting FGA score using TIS score, the $R^2$ was 0.193, and regression equation for predicting FGA score using TIS score, the $R^2$ was 0.181 in the group of FGA score ${\leq}15$. In the group of FGA score >15 for regression equation for predicting FGA score using TIS and BBS score, the $R^2$ was 0.327. In the group of FGA score ${\leq}15$ for regression equation for predicting FGA score using TIS and BBS score, the $R^2$ was 0.316. Conclusions: The TIS scores are insufficient in predicting the FGA and BBS scores in those with higher balance ability, and the BBS and TIS could be used for predicting variables for FGA. However, TIS is a strong predictive variable for persons with stroke who have poor balance ability.

• Water for future
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• v.24 no.4
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• pp.41-48
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• 1991

This paper describes the characteristics of tidal currents in the Gamag Bay by using the two-dimensional nonlinear hydrodynamic euation. The basic equations are derived by Navier-Stokes momentum equation and continuity equation and its characteristics critically are reviewed, and they are analysed by the implicit finite difference method. The numerical model is constructed two-dimensional(depth-averaged) simple layer model. This paper investigates the stability of solution and convergence of solution in application of the method to Gamag Bay, and the reproducibility of the simulation is also discussed in comparison with the results of field survey. The following items are clarifide through the numerical investigation; i)the reproduc-ibility of tidal range and currents are quite acceptable, comparing with the results of model tests and field data, and ii) tidal cycle for convergent solution is four tidal cycle, also, iii) bottom friction is successfully represented as c=(1/n))$h^{1/6}$.

• The Korean Journal of Health Service Management
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• v.5 no.2
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• pp.173-186
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• 2011

The purpose of this study was to know dysfunctions degree, daily living activity, depression and quality of life among stroke elderly person; and to know what kind of factors affecting to quality of life of the stroke elderly person; after that provide a fundamental data to nursing arbitration plan about increase height quality of life of the stroke elderly person. The study subjects were collected 119 people, over than 60 age, who were diagnosed with stoke in D hospital, living in B city. The data was collected by using personal interviews and questionnaire, from Nov 2008 to Jan 2009. The questionnaire were Pre-Stroke MRDS(Modified Rankin Disability Scale), Barthel-ADL(Activities of Daily Living), K-IADL(Korean-Instrumental Activities of Daily Living), GDS-15(Geriatric Depression Scale-15-question form) methods. The pre-stroke MRDS was appeared a functional obstacle. The mean score of activity of daily living was 18.24 which showed the subjects were mildly disabled, the score of instrumental activities of daily living was 7.94 which showed the mildly abled, and score of depressiveness was 7.41 which showed the subjects were mildly depression. There was a significantly correlation among MRDS, ADL, IADL, depressiveness and quality of life. Through these study result, important to check the old subjects' depressiveness, cognitive functions, daily living abilities, dysfunctions degree to main tain their quality of life.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.3
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• pp.608-618
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• 2007

Image binarization is an important preprocessing to identify the object of interest by dividing pixels into the background and object. We proposes efficient binarization method and a stroke reconstruction method of the low quality character image for an effective character recognition. First, the character image is binarized by using the both advantages of local and global thresholding method and then the noise elimination around the character stroke and the hole filling on the stoke by the analysis of the binarized stroke image are performed to enhance the quality of the character stroke. Proposed binarization algorithm for character image achieved an efficiency of both processing speed and performance by the adaptive threshold selection. Moreover, We could get a high qualify binary image by a stroke reconstruction of the step-by-step denoising process.