• Journal of The Korean Association For Science Education
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• v.25 no.5
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• pp.583-594
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• 2005

This study examined 8th-graders' conceptions of force on a simple pendulum and investigated cognitive conflict and conceptual change through kinesthetic experience in swing. Participants of this study were guided to anticipate the direction of total force acting on a pendulum at three critical positions and observed it through swing experience. Having completed this, students read an article explaining the results they observed. Most of them considered gravity, tension, and motion-force to be the real forces acting on a pendulum in pre-test. Though they were interested in the activity and conceded their expectations to be different from observed results, the degrees of their cognitive conflict were not significantly high. In summation, 'interest' was the highest and 'anxiety' was the lowest. Most of the students memorized the direction of forces on a swing, but few could explain the reason behind the occurrence in an immediate post-test and delayed post-test.

• Biomolecules & Therapeutics
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• v.19 no.2
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• pp.224-230
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• 2011

In order to develop silk peptide (SP) preparations possessing cognition-enhancing effect, several candidates were screened through in vitro assays, and their effectiveness was investigated in facilitated brain aging model rats. Incubation of brain acetyl-cholinesterase with SP-PN (1-1,000 ${\mu}g/ml$) led to inhibition of the enzyme activity up to 35%, in contrast to a negligible effect of SP-NN. The expression of choline acetyltransferase (ChAT) mRNA of neural stem cells expressing ChAT gene (F3.ChAT) was increased by 24-hour treatment with 10 and 100 ${\mu}g/ml$ SP-NN (1.35 and 2.20 folds) and SP-PN (2.40 and 1.34 folds). Four-week subcutaneous injections with D-galactose (150 mg/kg) increased activated hippocampal astrocytes to 1.7 folds (a marker of brain injury and aging), decreased acetylcholine concentration in cerebrospinal fluid by 45-50%, and thereby impaired learning and memory function in passive avoidance and water-maze performances. Oral treatment with SP preparations (50 or 300 mg/kg) for 5 weeks from 1 week prior to D-galactose injection exerted recovering activities on acetylcholine depletion and brain injury/aging as well as cognitive deficit induced by D-galactose. The results indicate that SP preparations restore cognitive functions of facilitated brain aging model rats by increasing the release of acetylcholine, in addition to neuroprotective activity.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2010.05a
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• pp.37-41
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• 2010

The previous investigations of electroencephalogram (EEG) activity in the memory retrieval tasks demonstrated that event-related potentials (ERP) during recollection showed different durations and the peak levels from those without recollection. However, it has been unknown that recollection in memory retrieval also modulates high-frequency brain rhythms as well as establishes large-scale synchronization across different cortical areas. In this study, we examined the spectral components of the EEG signals, especially the gamma bands (20-80Hz), measured during the memory retrieval tasks. Specifically, we focused on two major spectral components: first, we evaluated the temporal patterns of the power spectral density before and after the onset of the memory retrieval task; second, we estimated phase synchrony between all possible pairs of EEG channels to evaluate large-scale synchronization. Fourteen healthy subjects performed the memory retrieval task in the virtual reality environment where they selected whether or not t he present item was seen in the previous training period. When the subjects viewed the unseen items, the middle gamma power (40-60Hz) appeared to increase 200-500ms after stimulus onset while the low gamma power (20Hz) was suppressed all the way through the post-stimulus period 150ms after onset. The degree of phase synchronization in this low gamma level, however, increased when the subjects fetched the item from memory. This suggests that phase synchrony analysis might reveal different aspects of the memory retrieval process than the gamma power, providing additional information to the inference on the brain dynamics during memory retrieval.

• Journal of Korean Library and Information Science Society
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• v.48 no.1
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• pp.227-243
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• 2017

This study aims to explore older adults' experiences on cognitive and physical barriers and emotional changes of interactions from their health information seeking. Total of 10 older adults aged 65 or more were individually interviewed. The results show that the older adults may experience more difficulty from the perspectives on cognitive and physical barriers. The cognitive barriers are to: 1) know information resource and information search skills, 2) to choose relevant information, and 3) to know information search tools. The physical barriers for them to consider are eyes, hands, legs, and the whole body when accessing health information. In terms of emotion, the older adults express curiosity and negative emotion and at the beginning of the search and then they have more emotional expressions in the middle, and then they express positive emotion at the end of the search. The results suggest that information professionals should consider library as a connection to help them reduce these barriers and stabilize emotional changes.

• Korean Journal of Cognitive Science
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• v.28 no.1
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• pp.43-64
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• 2017

The purpose of the current study is to investigate how task-irrelevant affective priming affects higher cognitive function. In the study, we selected prime stimuli from International Affective Picture System(IAPS) and examined if they influence participants' performance of syllogistic reasoning task when they are task-irrelevant. In Experiment 1, arousal of IAPS stimuli was controlled while valence of the stimuli was manipulated. In Experiment 2, valence of IAPS stimuli was controlled while arousal of stimuli was manipulated. In both experiments, task-irrelevant affective primes were followed by syllogistic reasoning tasks consisting of three sentences and measured accuracies of task performance. The results showed that valence of affective prime affected logical validity of reasoning and belief-bias whereas arousal of affective primes did not yield any difference. That is, positive valence facilitated logical and analytic processing by reducing belief-bias while arousal did not affect reasoning task performance. These results suggest that dimensions of valence and arousal independently influence higher cognitive function.

• Journal of Korean Physical Therapy Science
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• v.6 no.2
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• pp.1007-1017
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• 1999

The purpose of this study was to evaluate the factors influencing the ambulatory status in hemiplegia with intracerebral hemorrhage after rehabilitation. Thirty patients with stroke who was admitted in the Chosun University Hospital, between from January 1st' 1998 and December 31st' 1998, were included in this study. The following variables as a potential predictors for ambulation were evaluated at treatment of the stroke onset; 1) general characteristics including age and sex, and 2) clinical characteristics including frequency and onset time of the stroke, affected side, duration of the treatment, time interval between onset and rehabilitation, manual muscle test of paretic limb, sitting and standing balance, proprioception, perception, cognitive function. We compared and analyzed the these variables to the two type of ambulatory status at the time of the discharge by Modified Barthel Index, independent, dependent. The data were analyzed by student t-test, Fisher-exact test, Mann Whitney-U test, $X^{2}$-test, correlation analysis(spearman's). The results were as follows; 1. Were no significantly inflenced independent ambulatory status among general characteristics. 2. Frequency of the stroke and proprioception (p<0.05), muscle strength of the lower limb, cognitive function and standing balance (p<0.01), perception and sitting balance (p<0.001) were significantly inflenced independent ambulatory status among clinical characteristics. 3. Independent Variable correlated with the ambulatory status were muscle strength of the lower limb, proprioception and sitting balance (p<0.05), standing balance, frequency of the stroke, perception and cognitive function (p<0.01). Therefore the muscle strength of the lower limb, proprioception, sitting balance, standing balance, frequency of the stroke, perception, cognitive function were the most significant influencing factors of ambulatory status after rehabilitation.

• Journal of The Korean Association For Science Education
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• v.21 no.4
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• pp.689-696
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• 2001

Students who have correct conception didn't show big changes in a test of cognitive conflict, while students who have misconception made significant changes Most students who had misconception were considerably curious about demonstration of an actual phenomenon. On the other hand, according to their own confidence of preconception, the higher confidence of misconception is, the bigger conflicts are and when they meet some different phenomenon unlike their ideas, their psychological shock was big. After a cognitive conflict lesson, students' conception was significantly changed regardless of students' confidence of preconception and the persistence effect new conceptions showed similar result as preceeding research regardless of confidence of preconception. That is, the change decreased from immediate after demonstration of an conflict situation to a week after. After conceptual change, students' confidence of correct conception was generally increased, so it turned out that cognitive conflict lesson had a positive effect on students who had a misconception.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.1
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• pp.91-107
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• 2014

Device-to-device (D2D) communication is an excellent technology to improve the system capacity by sharing the spectrum resources of cellular networks. Multicast service is considered as an effective transmission mode for the future mobile social contact services. Therefore, multicast based on D2D technology can exactly improve the spectrum resource efficiency. How to apply D2D technology to support multicast service is a new issue. In this paper, a resource allocation scheme based on cognitive radio (CR) for D2D underlay multicast communication (CR-DUM) is proposed to improve system performance. In the cognitive cellular system, the D2D users as secondary users employing multicast service form a group and reuse the cellular resources to accomplish a multicast transmission. The proposed scheme includes two steps. First, a channel allocation rule aiming to reduce the interference from cellular networks to receivers in D2D multicast group is proposed. Next, to maximize the total system throughput under the condition of interference and noise impairment, we formulate an optimal transmission power allocation jointly for the cellular and D2D multicast communications. Based on the channel allocation, optimal power solution is in a closed form and achieved by searching from a finite set and the interference between cellular and D2D multicast communication is coordinated. The simulation results show that the proposed method can not only ensure the quality of services (QoS), but also improve the system throughput.

• Journal of agriculture & life science
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• v.43 no.5
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• pp.27-32
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• 2009

This study purposed to examine the effect of the horticultural therapy on activities of daily living and cognitive function of demented old adults in facilities. According to the results of evaluating BADL, the ability to perform daily activities decreased from 9.71 to 9.21 in the control group, but in the experimental group, the ability to perform daily activities increased significantly(p=.009) from 10.86 before the horticultural therapy to 12.43 after the therapy. According to the results of evaluating K- MMSE, the score decreased from 10.57 to 9.07 in the control group, but the experimental group showed a significant improvement in cognitive functions from 10.43 before the horticultural therapy to 13.29 after the therapy(p=.003). As presented above, the horticultural therapy was effective in improving activities of daily living and cognitive function of demented old adults.

• Journal of dental hygiene science
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• v.19 no.3
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• pp.170-180
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• 2019

Background: Recently, competency-based education has been reorganized in the dental hygiene curriculum. In education, non-cognitive factors are emphasized. Grit, the non-cognitive ability to persevere to achieve an individual's long-term goals, is emerging. This study aims to identify the degree of grit and core competencies in students and to investigate the relationship between them and the factors that affect these core competencies. Methods: This study was conducted using 350 dental hygiene students who were randomly assigned a structured questionnaire to complete. The final analysis included 321 students. The survey contents evaluated grit, core competencies, and general characteristics. The difference in the degree of grit and core competencies in conjunction with the general characteristics of the subjects was analyzed using the t-test/Mann Whitney U-test and the ANOVA/Kruskal-Wallis H test. Multiple regression analysis was then conducted to determine the factors affecting the core competencies of the subjects. Results: The difference of 'grit' according to general characteristics was statistically significant in 'major satisfaction', 'relationship', 'perceived academic achievement', 'grade point average (GPA)'. The difference in 'core competency' according to general characteristics was statistically significant in 'grade', 'department selection', 'major satisfaction', 'relationship', 'perceived academic achievement', 'GPA'. Among the sub-areas of 'grit', 'perseverance of effort' showed a high correlation with 'core competency' and was statistically significant. As a result of regression analysis, 'major satisfaction', 'perceived academic achievement' and 'grit' of dental hygiene students had a statistically significant influence on 'core competency'. Meanwhile, 'GPA' was not seen to be statistically significant in 'core competency'. Conclusion: Grit, a non-cognitive factor, had a statistically significant effect on core competency, while the effects on GPA, a cognitive factor, were not statistically significant. Among the sub-factors of grit, 'perseverance of effort' had a statistically significant effect on 'problem-solving competency' and 'academic competency', which are 'core competency' sub factors.