• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.7
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• pp.1533-1546
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• 2013

Wireless multicast is considered as an effective transmission mode for the future mobile social contact services supported by Long Time Evolution (LTE). Though wireless multicast has an excellent resource efficiency, its performance suffers deterioration from the channel condition and wireless resource availability. Cognitive Radio (CR) and Device to Device (D2D) are two solutions to provide potential resource. However, resource allocation for cognitive wireless multicast based on D2D is still a great challenge for LTE social networks. In this paper, a joint sub-carriers and power allocation model based on D2D for general cognitive radio multicast (CR-D2D-MC) is proposed for Orthogonal Frequency-Division Multiplexing (OFDM) LTE systems. By opportunistically accessing the licensed spectrum, the maximized capacity for multiple cognitive multicast groups is achieved with the condition of the general scenario of imperfect spectrum sensing, the constrains of interference to primary users (PUs) and an upper-bound power of secondary users (SUs) acting as multicast source nodes. Furthermore, the fairness for multicast groups or unicast terminals is guaranteed by setting a lower-bound number of the subcarriers allocated to cognitive multicast groups. Lagrange duality algorithm is adopted to obtain the optimal solution to the proposed CR-D2D-MC model. The simulation results show that the proposed algorithm improves the performance of cognitive multicast groups and achieves a good balance between capacity and fairness.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.5
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• pp.8-14
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• 2008

There are two a approaches for the Cognitive Radio(CR) development. One is 'Full CR', which Joseph Mitola III proposed, and another is 'Spectrum CR', which is currently being standardized. The target approach of this paper is the latter and we develop a Cognitive Engine(CE) and simulated a channel set management(CSM), which is a core function of CE. The Channel set management evaluates channel quality and Incumbent User(IU) vacancy possibility and classifies the channel set, which is performed by using channel state history. Especially, a very important function for the channel set management is a channel state prediction and this paper proposed a Hidden Markov Model(HMM) based channel state prediction and a method for increasing performance. Also, we applied the proposed method into our simulator and simulated channel state prediction. Through the simulation, we verified as we applied our proposed scheme, the performance of channel state prediction gets better and through comparing with RS and SS, we verified the HMM based Channel state prediction is better.

• Journal of The Korean Society of Integrative Medicine
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• v.2 no.4
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• pp.91-100
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• 2014

Purpose : The purpose of this experiment is to find out the effectiveness which exert influence on cognitive skills by using the Driver Rehabilitation program for senior citizens who are over 65 years old and live in Busan. Method : From July first, 2014 to August 28th, 2014, we researched the 60 elderly people who are over 65 and go to community relief center which is in Busan. - 30 are experimental group and the other is control group. In the experimental group, we used Nintendo wii's driving simulation program and RC Car driving program in the model road. For estimation, we used MVPT-3(Motor-Free Visual Perception Test-3), Trail Making Test - 1, Trail making Test - 2 and LOTCA(Loewenstein Occupational Therapy Cognitive Assessment). Result : Nintendo wii's driving simulation program and RC Car driving program in model road results efficient visual perception ability. This programs results effectively in visual perception ability and space perception ability. This programs results effectively in motor apraxia ability. This programs results effectively in control ability for visual perception. This programs results effectively in thinking operation. Conclusion : Nintendo Wii's driving simulation program and RC Car driving program in model road positively influence improving for visual perceptual ability and cognitive function of elderly people. Also it is considered as being more efficient for improving visual perceptual ability and cognitive function to implement basic rehabilitation training with driving rehabilitation program than basic training itself.

• Journal of Digital Convergence
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• v.16 no.3
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• pp.513-525
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• 2018

The purpose of this study is to explore the experience of participants in the adventurous leisure activities and to examine the structural relations of the cognitive experience, the emotional experience and adherence intention. Robust quantitative measures were developed from rich qualitative data. The five dimensions selected from two preliminary tests were being away, technical enhancement, fascination with nature, challenge, and interpersonal trust. The cognitive dimensions have a significant effect on the emotional arousal - pleasure dimension. Our study also shows a positive causal relationship between emotional experience and adherence intention. Implications of this study include 1) a developed questionnaire for measuring the cognitive experience dimension of adventure leisure and establishing a foundation for future research, and 2) an identified psychological model among cognitive, emotion, and intention. We offer opportunities to better understand the psychological factors that motivate participation in adventure leisure.

• Journal of Korean Academy of Nursing
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• v.50 no.2
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• pp.191-199
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• 2020

Purpose: The purpose of this study was to compare sociodemographic characteristics of a normal cognitive group and mild cognitive impairment group, and establish prediction models of Mild Cognitive Impairment (MCI). Methods: This study was a secondary data analysis research using data from "the 4th Korea Longitudinal Study of Ageing" of the Korea Employment Information Service. A total of 6,405 individuals, including 1,329 individuals with MCI and 5,076 individuals with normal cognitive abilities, were part of the study. Based on the panel survey items, the research used 28 variables. The methods of analysis included a χ²-test, logistic regression analysis, decision tree analysis, predicted error rate, and an ROC curve calculated using SPSS 23.0 and SAS 13.2. Results: In the MCI group, the mean age was 71.4 and 65.8% of the participants was women. There were statistically significant differences in gender, age, and education in both groups. Predictors of MCI determined by using a logistic regression analysis were gender, age, education, instrumental activity of daily living (IADL), perceived health status, participation group, cultural activities, and life satisfaction. Decision tree analysis of predictors of MCI identified education, age, life satisfaction, and IADL as predictors. Conclusion: The accuracy of logistic regression model for MCI is slightly higher than that of decision tree model. The implementation of the prediction model for MCI established in this study may be utilized to identify middle-aged and elderly people with risks of MCI. Therefore, this study may contribute to the prevention and reduction of dementia.

• Knowledge Management Research
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• v.23 no.4
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• pp.159-175
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• 2022

As creativity is a crucial attribute for companies' survival and innovative success, many firms encourage and implement ways to promote employee creativity. Previous studies in the dual pathway to creativity model have shown that creativity can be enhanced when either the cognitive flexibility or cognitive persistence path is triggered. Although individuals have different personal traits, prior research has rarely investigated whether one pathway is more effective for a certain personality in promoting creativity than the other. Using attachment theory, we examined the influence of attachment style on the degree of the impact of each path on creativity. Specifically, we hypothesized that securely attached people would show higher creativity only when they use the cognitive flexibility path. Data from the US support our hypothesis. Our research highlights that the link between cognitive flexibility and creativity is salient when securely attached people use the cognitive flexibility path because of the strong fit between secure attachment and flexible thinking.

• Journal of the Korean Magnetics Society
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• v.26 no.5
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• pp.159-167
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• 2016

We have examined the perceptions of 6th grade elementary school students' conceptions on the magnetic fields of a permanent magnet by cognitive style. Students' conceptions on the magnetic fields of permanent magnet after the iron powder experiment are grouped into four models; Partial Distribution Model (PDM), Pole Separation Model (PSM), Homogeneous Distribution Model (HDM), and Field Model (FM). After the experiment to observe the magnetic field of the permanent magnet with compass, the students' conceptions are grouped into three models; Pole Separation Model (PSM), Complex Homogeneous Distribution Model (CHDM), and Field Model (FM). And after the application of the alternative experimental method to observe the magnetic field with only one compass, students' conceptions on magnetic field has been enhanced in both field-dependent and general-cognitive groups of students.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2005.05a
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• pp.9-13
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• 2005

A comprehension-based computational model of pilot action planning called ADAPT is presented to model pilot performance in a flight simulation context. Individual pilots were asked to execute a series of flight maneuvers using a flight simulator, and their eye-scanning, control movements, and flight performance were recorded in a time-synched database. Computational models of each of the 25 individual pilots were constructed, and the individual models simulated execution of the same flight maneuvers performed by human pilots. The time-synched eye-scanning, control movements, and flight performance of individual pilots and their respective models were compared to test ADAPT's predictive validity.

• Korean Journal of Child Studies
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• v.25 no.4
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• pp.17-32
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• 2004

Factor analysis of data collected from 336 elementary school children provided difficuitness and susceptibility as the temperament factors, and affect and control as the nurturing factors. Results showed that non-susceptible children with low controlling mother perceived their cognitive competence positively while highly susceptible children showed no differences in their self-competence by mothers' controlling behavior. Perceived cognitive competence of susceptible boys and of susceptible 3rd graders were low when their mothers asserted low control. Thus, mothers' controlling behavior supported perceived cognitive competence in highly susceptible boys and 3rd graders. That is, the effect of mother's behavior on child's self-competence was moderated by child's characteristics. These results partially supported the Conditional Model.

• Korean Journal of Child Studies
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• v.29 no.4
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• pp.79-95
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• 2008

This study investigated developmental pathways mediating effects of child abuse on peer rejection. Participants were 904 poor children aged 10-15 from 16 nationwide cities/provinces who receive financial sponsorship from Childfund in cooperation with the Ministry for Health, Welfare and Family Affairs. Structural equation modeling was employed for statistical analyses. Results showed that child abuse was directly associated with heightened risk of rejection by peers; the relationship was indirectly mediated by aggression and cognitive ability. The hypothesized partially mediated model had a better model fit than the fully mediated model. Aggression and low cognitive ability, significant effects of abuse, were associated with peer rejection. Social withdrawal, also associated with child abuse, did not account for the association between abuse and peer rejection.