• Journal of Korean Library and Information Science Society
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• v.22
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• pp.245-276
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• 1995

This study analyzed the process of information service and its factors in the cognitive viewpoint. And developed a conceptual model to help in developing future information systems and services. The results of this study were summarized as follows : 1) The paradigm of information user study is changing from the system-centered to the user-centered one. 2) The researchers describe the user's internal cognitive process as the starting point of the information service. 3) The user's personal cognitive process influence the process of the information service over. And the focus is a microscopic one including the factors of the perception and recognition of the stimulus, remembering and searching information, reasoning the rules, recognition of the patterns, formalization of the concepts, etc. 4) The information librarian performs the role as a knowledge/ information system interface, and his knowledge structure reflects the organization of that knowledge/information system. 5) The information librarians can perform their role as information specialists actively and offensively. And the performance of the librarians can be measured on the scales of the su n.0, pplying capability of relevant information and the client satisfaction.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.3A
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• pp.287-295
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• 2011

Cognitive radio (CR) features opportunistic access to spectrum when licensed users (LU) are not operating. To avoid interference to LU, cognitive users (CU) need to perform spectrum sensing. Because of local shadowing, fading, or limited sensing capability, it is suggested that multiple CUs cooperate to detect LU. In cooperative spectrum sensing, CUs should exchange their sensing data with minimum bandwidth and delay. In this paper, we introduce a novel method to efficiently report sensing data to the central node in an infrastructured OFDM-based CR network. All CUs simultaneously report their sensing data over unique and orthogonal signals on locally available subcarriers. By detecting the signals, the central node can determine subcarrier availability for each CU. Implementation challenges are identified and then their solutions are suggested. The proposed method is evaluated through simulation on a realistic channel model. The results show that the proposed method is feasible and efficient.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.1
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• pp.193-198
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• 2005

Changes in visuospatial cognitive performance, blood oxygen saturation and heart rate due to the highly concentrated oxygen administration were observed in this study. Six male ($25.8 \pm$1.0) and six female (($23.8 \pm$ 1.9) adults were asked to perform 20 visuospatial tasks with the same level of difficulties by supplying two different oxygen levels (21%, 30%). Experiment consisted of Rest1 (1 min.), Control (1 min.), Task (4 min.), and Rest2 (4 min.) and physiological signals such as blood oxygen saturation and heart rate were measured through each stage. The result showed the accuracy of task performance increased significantly at 30% oxygen concentration compared with 21%, which means oxygen supply has positive effects on visuospatial cognitive performance. When 30% oxygen was supplied, blood oxygen saturation during control and task phases was increased and heart rate was decreased compared with 21%. It means that 30% oxygen can stimulate brain activities by directly increasing the actual level of blood oxygen concentration during cognitive performance, and enough oxygen supply during cognitive performance make heart rate decrease.

• 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.

• Clinical Psychopharmacology and Neuroscience
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• v.16 no.4
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• pp.481-488
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• 2018

Preliminary studies have claimed that short term fasting would negatively affect school performance and cognition. In contrast some other studies have reported not important decline in cognition and executive function as a result of fasting. Also limited attention was generally devoted to dietetic regimens, nutritional status and body weight. Yet neuroscience and neuro-cognitive aspects of acute hunger on the electroencephalogram and differences between obese and non-obese cases is not well understood. Hence, we decided to design and perform a case study in a more controlled situation similar to reality. Therefore, we performed several examinations including subjective tests (for eating status) and objective tests (cognitive tests such as Stroop effect and Sternberg search and electroencephalogram measures such as steady-state visual evoked potential and auditory steady-state responses) for an obese and a non-obese academic case before and after a simple breakfast. The results showed that the breakfast effects on the neuro-cognitive functions depend on either obesity status, nutritional status of the case or the type of cognitive task (visual or auditory). This paper would open a new insight to answer some important questions about the neuro-cognitive implications of fasting and feeding in obese and non-obese human cases.

• Journal of Korean Elementary Science Education
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• v.24 no.1
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• pp.86-101
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• 2005

In this study, a brain-basrd model for science teaching and learning was developed based on the natural processes which human acquire knowledge about a natural object or on event, the major domains of science educational objectives of the national curriculum, and the human brain's organizational patterns and functions. In the model, each educational objective domain is related to the brain regions as follows: The affective domain is related to the limbic system, especially amygdala of human brain which is involved in emotions, the psychomotor domain is related to the occipital lobes of human brain which perform visual processing, temporal lobes which perform functions of language generating and understandng, and parietal lobes which receive and process sensory information and execute motor activities of body, and the cognitive domain is related to the frontal and prefrontal lobes which are involved in think-ing, planning, judging, and problem solving. The model is a kind of procedural model which proceed fiom affective domain to psychomotor domain, and to cognitive domain of science educational objective system, and emphasize the order of each step and authentic assessment at each step. The model has both properties of circularity and network of activities. At classrooms, the model can be used as various forms according to subjects and student characteristics. STS themes can be appropriately covered by the model.

• 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.

• Progress in Medical Physics
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• v.21 no.1
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• pp.42-51
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• 2010

Imaging studies using MRI, PET, and/or MEG have been primary evaluation methods to quantitatively assess cognitive function. Recent advances in computational technology and information technology may allow a novel evaluation methodology to quantitate cognitive function more cost-effectively. In this study, we developed a software package composed of a series of tests to evaluate cognitive ability combined with a user-friendly touch screen input device. This cognitive assessment tool can quantitate concentration, numeric memory, associative memory, topological memory, visual and muscular reaction, and acoustic reaction over a relatively short testing time. We performed an empirical study on eighty normal subjects aged 20 and 59 years old using the developed evaluation methods. Age-related cognitive deterioration after 40 years old was confirmed. There was no difference in cognitive ability between male and female in the same age group. This study demonstrates the feasibility of a simple but effective evaluation software tool to quantitatively assess cognitive ability. This methodology may provide improved accessibility and reduced costs to perform cognitive function studies to compare between various subject groups.

• Physical Therapy Korea
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• v.16 no.4
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• pp.44-52
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• 2009

It is known that individual factors as cognitive, perception, emotion, and motivation may greatly influence on recovery from neurologic region. This study was to investigate the effects of environmental reinforcement through motivation to perform the tasks voluntarily on motor and cognition function in rats with focal ischemic brain injury. Focal ischemic brain injury was induced in Sprague-Dawley rats (15 rats, $250{\pm}50$ g) through middle cerebral artery occlusion (MCAo). And then, experiment groups were randomly divided into three groups; The control group: MCAo induction ($n_1$=5), the environmental reinforcement (ER) group: the application for ER after MCAo induction ($n_2$=5), the environmental reinforcement through motivation (ERM) group: the application for ERM after MCAo induction ($n_3$=5). The climbing test (CT) and the modified limb placing tests (MLPTs) to measure the motor function and the Morris water maze acquisition test (MWMAT) and the Morris water maze retention test (MWMRT) to measure the cognitive function were performed. For the CT, the ERM group was significantly larger than the ER group. For the MLPTs, the ERM group was significantly decreased compared to other groups. For the MWMAT, the time to find the circular platform in the ERM group significantly decreased compared to other groups. For the MWMRT, the time to dwell on the quadrant circular platform in the ERM group was significantly increased compared to other groups. These results suggested that the ERM could improve the motor and cognitive functions in the rats with focal ischemic brain injury.

• Journal of Biomedical Engineering Research
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• v.26 no.1
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• pp.1-7
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• 2005

This study aimed to investigate the hypothesis that administration of the air with 30% oxygen compared with normal air (21% oxygen) enhances cognitive functioning through increased activation in the brain. Seventeen college students (right­handed, average age of 24.3) were selected as subjects for this study. An oxygen supply equipment that provides 21% and 30% oxygen at a constant rate of 8L/min was developed. In order to measure the performance level of visuospatial and verbal cognition, two psychological tests were developed. The experiment consisted of two runs, one for cognition task with normal air (21% oxygen) and the other for cognition task with hyperoxic air (30% oxygen). Visuospatial and verbal tasks were presented while brain images were scanned by a 3T fMRI system using the single-shot EPI method. The results showed that there was an improvement in performance and also increased activation in several brain areas in the higher oxygen condition. These results suggest that while performing cognitive tasks, high concentrations of oxygen administration make oxygen administration sufficient, thus making neural network activate more, and the ability to perform cognitive tasks increase.