• Journal of Communications and Networks
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• v.14 no.6
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• pp.710-718
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• 2012

The implementation of a common control channel is one of the most challenging issues in cognitive radio networks, since a fully reliable control channel cannot be created without reserving bandwidth specifically for this purpose. In this paper, we investigate a promising solution that exploits the ultra wide band (UWB) technology to let cognitive radio nodes discover each other and exchange control information for establishing a communication link. The contribution of this paper is threefold: (i) We define the communication protocol needed to let cognitive radio nodes discover each other and exchange control information for link set up, (ii) we overcome the gap in coverage, which typically exists between UWB and long-medium range technologies, by using multi-hop communication, (iii) we evaluate the performance of our approach by adopting an accurate channel model and show its benefits with respect to an in-band signaling solution.

• Korean Journal of Child Studies
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• v.33 no.3
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• pp.1-22
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• 2012

The purpose of this study was to examine the relationships between parents' control, affectionate parenting behavior, preschooler's effortful control, prosocial behavior, and cognitive problem-solving ability. The subjects for this study comprised 221 preschoolers (104 boys, 117 girls) and their parents. The major results of this study were as follows. First, parents' effortful control revealed direct effects upon preschooler's effortful control, and affectionate parenting behavior mediated the effects of parents' effortful control upon preschooler's effortful control. Second, preschooler's effortful control mediated the effects of affectionate parenting behavior upon preschooler's prosocial behavior. Third, preschooler's effortful control had direct effects upon prosocial behavior, and prosocial behavior mediated the effects of preschooler's effortful control upon cognitive problem-solving ability. In conclusion, parents' effortful control and affectionate parenting behavior impacted upon preschooler's effortful control. And preschooler's effortful control had an important role upon prosocial behavior and cognitive problem-solving ability.

• Journal of Korean Academy of Nursing
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• v.47 no.1
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• pp.1-13
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• 2017

Purpose: The purpose of this study was to examine the effects of a cognitive training program on neurocognitive task performance and activities of daily living (ADL) in patients who had a stroke. Methods: The research design for this study was a nonequivalent control group non-synchronized design. Patients were assigned to the experimental (n=21) or control group (n=21). The experimental group received a 4-week cognitive training program and usual care (i.e., rehabilitation service), while the control was received usual care only. Cognitive function was measured with a standardized neurocognitive test battery and ADL was assessed at baseline and one and two months after completion of the intervention. Repeated measures ANOVA was used to determine changes in cognitive function and ADL over 2 months. Results: The interaction of group and time was significant indicating that the experimental group showed improvement in attention, visuospatial function, verbal memory, and executive function compared to the control group which had a sustained or gradual decrease in test performance. A significant group by time interaction in instrumental ADL was also found between the experimental group with gradual improvement and the control group showing no noticeable change. Conclusion: Findings show that the cognitive training program developed in this study is beneficial in restoring cognitive function and improving ADL in patients following a stroke. Further study is needed to investigate the long-term relationship between cognitive training participation and cognitive improvement and effective functioning in daily living.

• Journal of Korean Academy of Medicine & Therapy Science
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• v.10 no.2
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• pp.13-20
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• 2018

Objective: To investigate the effects of a brain fitness exercise on the cognitive function of patients with dementia. Method: Forty-six elderly adults diagnosed with dementia were randomly allocated to the study or control group (n=23 per group). The study and control groups performed a brain fitness and regular exercise, respectively, for 40 minutes a day, three times a week for four weeks. We examined cognitive capacity using MMSE-K, cognitive strength, judgment time, and mental workload scores before and after intervention. Results: The study group showed significant improvements in all variables. In addition, the control group showed a significant improvement in brain stress. We found that there was a significant improvement in the study group when compared with the control group in all variables. Conclusion: Based on these results, we suggest that brain fitness exercise would be effective in improving cognitive functions of dementia patients.

• Journal of the Korean Society of Physical Medicine
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• v.12 no.1
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• pp.51-59
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• 2017

PURPOSE: This study compared cognitive task-directed functional motor control ability for reaching and kicking movements in younger and older adults. METHODS: Subjects were divided into two groups of younger and older adults, with 13 subjects in each group. Subjects were required to perform a dual task combining a functional movement and cognitive component. The task consisted of reaching and kicking movements. Participants performed indicated movements when a target appeared on a monitor. The target randomly appeared on the monitor every 10 seconds. The total performance time (TPT), joint angular velocity (JAV), and muscle activation time were used to evaluate motor control ability. RESULTS: There were significant differences in all evaluation factors in a comparison of younger and older adults (p<.05). TPT was significantly shorter in older adults, and JAV and muscle activation time were significantly slower than that in the younger adult group. Although the results for older adults were within the normal range for functional assessment, their motor control abilities were significantly worse for cognitive tasks compared with those of younger adults. CONCLUSION: The results of this study indicated that a motor control assessment tool using a cognitive task would be helpful in assessment of motor control ability in healthy older adults.

• Journal of the Korean Society of Physical Medicine
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• v.13 no.4
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• pp.59-65
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• 2018

PURPOSE: The purpose of the present study is to investigate the changes in the cognitive function of elderly dementia patients residing in a residential care facility, following six weeks of brain-computer interface (BCI)-based cognitive training and to determine whether BCI-based cognitive training effectively improves their cognitive functions. METHODS: Thirty subjects diagnosed with dementia were randomly assigned to either the experimental or control group. Pre- and post-test cognitive function assessments were conducted using the mini mental state examination-Korean (MMSE-K) and Korean-dementia rating scale (K-DRS). The experimental group received BCI-based cognitive training, which consisted of games such as flying a ball and exploding a bomb, while the control group participated in music listening activities and National Health Gymnastics. Both groups engaged in a total of 18 sessions (3 times per week for 6 weeks, for 40 minutes per session). RESULTS: After 6 weeks of intervention, the experimental group had significantly increased MMSE-K scores ($19.53{\pm}1.30$ to $22.20{\pm}1.15$; p<.0011) and total K-DRS scores ($87.20{\pm}4.16$ to $99.33{\pm}1.15$; p<.0011). In addition, the experimental group showed greater cognitive improvements than the control group. CONCLUSION: The results of this study suggest that BCI-based cognitive training is a positive intervention tool for improving the cognitive function of dementia patients.

• Human Ecology Research
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• v.58 no.1
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• pp.61-74
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• 2020

This study examined the effects of moral disengagement (cognitive restructuring and blaming the victim) and self-control on cyberbullying perpetration and investigated if self-control moderated the relationship between moral disengagement (cognitive restructuring and blaming the victim) and cyberbullying perpetration. Participants in the study consisted of 551 middle school students (273 boys and 278 girls) from five middle schools in Seoul and Gyeonggi-do. Cyberbullying perpetration, moral disengagement and self-control were measured using the Bullying/Victimization Questionnaire, the Mechanisms of Moral Disengagement Scale, and the Self-Control Scale for children and adolescents. Data were analyzed by means of descriptive statistics and a hierarchical regression analysis. The moderating effect of self-control was analyzed using procedures proposed by Baron and Kenny (1986). The results indicated that both levels of cognitive restructuring and blaming the victim increased cyberbullying perpetration whereas the level of self-control decreased cyberbullying perpetration. In addition, self-control moderated the effect of cognitive restructuring on cyberbullying perpetration. The influence of cognitive restructuring on cyberbullying perpetration was greater when the level of self-control was low, compared to when it was high.

• Journal of Christian Education in Korea
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• v.74
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• pp.255-271
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• 2023

Purpose of study: The purpose of this study is to explore the moderating effect of learning motivation in the effect of cognitive presence on cognitive regulation. Research content and method: The subjects of this study were 160 preservice teachers who are enrolled in the Faculty of Education of a university. The survey measured cognitive control, human presence, and learning motivation. Among the collected data, learning motivation was averaged. In addition, a group with low learning motivation and a group with high motivation were distinguished. Next, this study compared the averages of cognitive control by classifying the learning motivation levels. The collected data was analyzed using a multiple regression (Stepwise) method to explore the effect of cognitive presence on cognitive control. First, multiple regression analysis was performed on the entire group. Second, multiple regression analysis was performed by dividing the group with low learning motivation from the group with high motivation. Conclusions and Suggestions: As a result of the analysis, the group with high learning motivation showed a higher level of cognitive control than the group with low motivation. In the group with high learning motivation, only content understanding among the sub-factors of cognitive presence had an effect on cognitive control. In the group with low learning motivation, all factors of cognitive presence were affected.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.3
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• pp.33-40
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• 2019

Purpose : The purpose of this randomized controlled trial study was to examine the effect of transcranial direct current stimulation (tDCS) on cognitive function and depression in stroke patients. Methods : Thirty stroke patients were randomly divided into an experimental group (n = 15) and a control group (n = 15). The experimental group received tDCS while performing computerized cognitive rehabilitation programs, and the control group was provided with sham tDCS while operating the same programs. The 30-minute intervention was implemented five times per week for six weeks. To assess cognitive function before and after the intervention, the Neurobehavioral Cognitive Status Examination was conducted; the Beck Depression Inventory BDI was employed to assess depression. Results : The experimental group showed statistically significant increases in cognitive function and decreases in depression (p < .05 ). Comparing the amount of variation between the groups after arbitration also showed significant differences in cognitive function and depression between the two groups (p > .05). Conclusion : The application of tDCS and computerized cognitive rehabilitation programs for stroke patients may positively affect their cognitive function and depression. Therefore, tDCS used with computerized cognitive rehabilitation programs is positively applicable to the enhancement of cognitive function in stroke patients and reduction of depression.

• Journal of Korean Critical Care Nursing
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• v.14 no.1
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• pp.50-62
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• 2021

Purpose : This study examined the effects of an integrated management program on physical function, cognitive function, and depression in patients with subacute stroke. Methods : A nonequivalent control group design was adopted. The participants were assigned to either the experimental group (n=20) or control group (n=23). The experimental group received an 8-week integrated management program and standard rehabilitation service (i.e., physical therapy and occupational therapy), while the control group received the standard rehabilitation service only. Physical function was measured as gait speed and balance ability using the Berg Balance Scale (BBS). Cognitive function was measured with neuro-behavioral cognitive status examination (NCSE), and depression was measured using the Beck Depression Inventory-II (BDI-II). Repeated measure ANOVA was used to determine changes in physical function, cognitive function, and depression over 8-weeks. Results : The interaction between group and time was significant, indicating that the experimental group showed improvement in gait speed, balance ability, cognitive function (linguistic ability, linguistic memory, reasoning), and a decrease in depression compared to the control group. Conclusion : These results indicate that the integrated management program developed herein was beneficial in restoring physical function, cognitive function, and depression in subacute stroke patients.