• Korean Journal of Cognitive Science
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• v.31 no.1
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• pp.1-23
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• 2020

This paper introduces SNUDM, an analysis program for Ratcliff's diffusion model, which has been one of the most important models in cognitive psychology over the past 35 years and which has come to occupy an important place in cognitive neuroscience in recent years. The analysis tool is designed with the basic principles of easy comprehension and simplicity in use. A diffusion process was programmed as the limit of a simple random walk in a manner resembling Ratcliff & Tuerlinckx(2002). The response time distribution of the model was constructed by simulating the time taken by a random walk until it reaches a threshold with small steps. The optimal parameter values in the model are found to be the smallest value of the chi-square values obtained by comparing the resulting distribution and the experimental data using Simplex method. For simplicity and ease of use, the input file used here is created as a file containing the quantile of the reaction time, the trials and other information. The number of participants and the number of conditions required for such work programs are given in a way that answers the question. Using this analysis tool, the experimental data of Ratcliff, Gomez, & McKoon(2004) were analyzed. We found the very similar pattern of parameter values to Ratcliff et al.(2004) found. When comparing DMAT, fast-dm and SNUDM with the generated data, we found that when the number of trials is small, SNUDM estimates the boundary parameter to a value similar to fast-dm and less than the DMAT. In addition, when the number of trials was large, it was confirmed that all three tools estimate parameters similarly.

• Korean Journal of Cognitive Science
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• v.33 no.3
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• pp.155-168
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• 2022

In this paper, we introduce the SNUDM-G, a diffusion model analysis tool with improved computational speed. Although the diffusion model has been applied to explain various cognitive tasks, its use was limited due to computational difficulties. In particular, SNUDM(Koh et al., 2020), one of the diffusion model analysis tools, has a disadvantage in terms of processing speed because it sequentially generates 20,000 data when approximating the diffusion process. To overcome this limitation, we propose to use graphic processing units(GPU) in the process of approximating the diffusion process with a random walk process. Since 20,000 data can be generated in parallel using the graphic processing units, the estimation speed can be increased compared to generating data through sequential processing. As a result of analyzing the data of Experiment 1 by Ratcliff et al. (2004) and recovering the parameters with SNUDM-G using GPU and SNUDM using CPU, SNUDM-G estimated slightly higher values for certain parameters than SNUDM. However, in term of computational speed, SNUDM-G estimated the parameters much faster than SNUDM. This result shows that a more efficient diffusion model analysis for various cognitive tasks is possible using this tool and further suggests that the processing speed of various cognitive models can be improved by using graphic processing units in the future.

• 한국노년학
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• v.29 no.4
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• pp.1397-1411
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• 2009

This study was aimed to examine the effects of intermittent walking on health related fitness and metabolic syndrome risk factors in elderly women. Forty five elderly women were randomly assigned to three groups: three 10-min walks per day, one 30-min walk per day or no exercise, respectively. Both walking groups exercised three days a week at moderate intensity for 12 weeks. Two-way repeated measures ANOVA was used to test the hypothesis with a significant level of α = .05. The results indicated that body composition(body weight, body mass index, percent body fat), muscle endurance, flexibility and cardiorespiratory fitness significantly increased after 12 weeks for both walking groups. However, it was found that muscle strength significantly increased only in a continuous walking group. Metabolic syndrome risk factors comprised of waist circumference, systolic blood pressure, triglyceride, high-density lipoprotein, and fasting glucose were significantly improved in both walking groups. In addition, there was a difference in these metabolic syndrome risk factors between pre and post exercise. The results of this study support the hypothesis that intermittent walking has a significant impact on health related physical fitness and metabolic syndrome rick factors in elderly women as continuous walking does.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.487-494
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• 2013

The purpose of this study was to determine the effect of mechanical horseback riding training on trunk control, balance function in stroke patients. 15 stroke patients were recruited for this study. The subjects were randomly assigned to two groups: experimental(n=7) and control(n=8). All subjects received a routine physical therapy. The mechanical horseback riding training was for 30 min in the case of the EG subjects. This study was carried out approximately 8 weeks from March 4 to May 3. The assessment tools of this study involved the trunk control test, postural assessment scale for stroke, Berg balance scale and timed up and go test. The measurements were recorded before the intervention and after the intervention. In the cases of the EG subjects and CG subjects, the variables measured after the intervention significantly differed from trunk control test, postural assessment scale for stroke, Berg balance scale and timed up and go test before the intervention (p<.05). Also, there were significant differences in trunk control test, postural assessment scale for stroke, Berg balance scale and timed up and go test at post test between the 2 groups (p<.05). The findings indicate that mechanical horseback riding training exerts a positive effect on trunk control, balance function in stroke patients. Further studies are required to generalize the result of this study.

• Journal of the Korean Society of Physical Medicine
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• v.8 no.2
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• pp.201-207
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• 2013

연구목적: 닌텐도 위를 이용한 가상현실기반 비디오게임 프로그램을 만성기 뇌졸중 환자에게 적용하여 균형능력 및 일상생활동작에 어떠한 영향을 미치는지 알아보고, 뇌졸중 환자의 재활프로그램으로서 적용 가능성이 있는지 알아보고자 한다. 연구방법: 만성기 뇌졸중 환자를 무작위로 가상현실기반 비디오게임 프로그램을 적용한 실험군(n=7)과 적용하지 않은 대조군(n=10)으로 구분하여 연구를 진행하였다. 연구에 참여한 모든 대상자에게 30분의 Bobath therapy와 15분간의 FES 치료를 기본적으로 실시하였다. 이에 더하여 실험군은 가상현실기반 비디오게임 프로그램을 1일 30분이내, 주 5회, 3주간 실시하였다. 대조군은 자전거 운동과 보행훈련으로 30분간 시행하였다. 실험 전 후 눈뜨고 외발서기(OLST; open leg standing test), Timed Up and Go(TUG) 검사, 10m 걷기 검사, Functional Independence Measure(FIM)를 측정하였다. 실험 전과 실험 후 측정값의 차이를 비교하기 위해 Wilcoxon Signed Ranks Test를 실시하였다. 그리고 각 측정값의 변화량에 대한 실험군과 대조군 사이의 차이를 알아보기 위해 Mann-Whitney U Test를 실시하였다. 연구결과: 실험결과는 다음과 같다. 1) 실험군에서는 FIM의 유의한 증가와 TUG, 10m 걷기 검사의 유의한 감소를(p<.05) 보였다. 대조군에서는 OLST의 증가와 TUG, 10m walking test의 감소가 나타났지만 통계적으로 유의하지 않았다. 오직 FIM에서만 유의한 증가가 나타났다(p<.05). 2) 실험 전 후의 실험군과 대조군의 각 측정값들의 평균차를 비교한 결과 실험군은 대조군보다 실험 전 후 OLST, TUG, 10m walking test 차이의 평균은 컸지만 통계적으로 유의하지 않았다. 결론: 이상의 결과로부터 가상현실기반 비디오게임이 만성기 뇌졸중 환자의 동적균형능력 및 일상생활동작 향상에 효과가 있음을 알 수 있었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.422-428
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• 2018

This study was conducted to investigate the effects of trunk stability exercise on knee function, balance and gait in patients who underwent total knee arthroplasty. The subjects of this study were recruited from individuals diagnosed with degenerative arthritis who had undergone total knee arthroplasty. Overall, 24 patients were randomly divided into a control groups and an experimental groups (12 each). The trunk stability exercise was conducted for 4 weeks with three exercises developed in a previous study. The measurement tools used were knee function measurements based on the Lysholm knee score, balance ability measured using a test of TUG and OLS, and a walking ability test measured using a 10MWT. Pre and post test results were within groups were compared using the paired t-test, whole differences between groups were compared using the independent t-test. The experimental group showed significantly enhanced results relative to the control group (p<0.05). Based on these results, trunk stability exercise in parallel with knee joint therapy effectively improves the recovery of patients with total knee arthroplasty.

• Journal of Digital Convergence
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• v.11 no.11
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• pp.537-544
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• 2013

This study was to determine the effect of 12-week balance training with visual feedback on balance and walking functions in patients with post-stroke hemiparesis. Twenty individuals with chronic stroke volunteered to participate in this study. They were randomly allocated to either experimental group (EG) or control group (CG), with 10 subjects in each group. Subjects from the group 1 underwent 15-min balance training with visual feedback and 15-min routine-scheduled physical therapy, and subjects from the group 2 performed 30-min routine-scheduled physical therapy only, which comprised mat exercise, strengthening, postural correction, and functional practice. Assessment tools were made with the Functional Reach Test (FRT), Timed Up and Go Test (TUGT), and 6 Min Walk Test (6MWT). In within-group comparison, the EG showed significant differences in all parameters (p<0.05), while significant differences were not found for the CG (p>0.05). In between-group comparison, the change values of the FRT and 6MWT appeared to be significantly greater for the EG than those of the CG (p<0.05). These findings suggest that balance training with visual feedback may be favorably used to improve balance and walking functions in patients with chronic post-stroke hemiparesis. Further studies with larger sample and long-term follow-up period need to generalize the results of this study.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.119-126
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• 2019

This study was conducted to investigate the effects of task oriented training on motor and cognitive function recovery in rats with induced Alzheimer's dementia. Thirty Sprague-Dawley rats were randomly assigned to a control group (n=15) and an experimental group (n=15). Training was given three times a week, for 20 minutes a session for 4 weeks. The cognitive and motor functions of the rats were evaluated by an eight arm radial maze test and ladder rung walk test. The eight arm radial maze test showed significant differences between groups according to the time of day 14 and 28 (p<.001). The difference in measured values according to the timing of the two groups was significant (p<.001). Additionally, there was a significant difference between the time and the group interaction (p<.001). The ladder rung walk test showed significant differences between groups according to the time of day 14 and 28 (p<.001). The difference in the measured values according to the timing of the two groups was significant (p<.001), and there was a significant difference between the time and the group interaction (p<.001). As a result, task oriented training for Alzheimer's dementia rats was found to have a positive effect on recovery of motor and cognitive function.

• Journal of Convergence for Information Technology
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• v.9 no.5
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• pp.172-179
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• 2019

The purpose of this study was to investigate the effects of virtual reality game based training on balance and upper limb function in subacute stroke patients. Thirty patients with subacute stroke were randomly assigned to experimental groups(n=15) and control groups(n=15) applying virtual reality game-based training programs. Intervention is applied three times a week for 6 weeks, 30 minutes for 1 time. In the study group, there was a significant improvement in balance ability, upper extremity function, and trunk impairment scale(p<.05), and the difference between the two groups was significant in the BBS, TUG, TIS(p<.05). Based on these results, the virtual reality game based training program is clinically useful exercise program for subacute stroke patients.

• Journal of the Korea Society of Computer and Information
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• v.26 no.8
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• pp.165-172
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• 2021

The purpose of this meta-analysis was to determine the efficacy of proprioceptive neuromuscular facilitation training on Gait. We included all randomized controlled trials assessing the efficacy of proprioceptive neuromuscular facilitation training on gait ability control in patients after stroke. This study was conducted according to the PRISMA guideline. CINAHL, PubMed and RISS were searched for studies published up to December 2020, and all randomized controlled trails assessing PNF intervention were included. This analysis included only randomized controlled trials. A total of 12 studies were selected from 1475 records obtained from the databases. The meta-analysis was performed using the R software. The overall intervention effect was moderate (standardized mean difference (SMD): 0.67, 95% confidence interval (CI): 0.50-0.84). Additionally, Gait rite (SMD: 0.69), 10m walking test (SMD: 0.59) had medium effect sizes. These findings indicate that PNF is an effective intervention for improving gait ability in patients stroke.