• Journal of IKEEE
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• v.14 no.4
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• pp.257-262
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• 2010

We design a CMOS front-end with wide variable gain and low power consumption for 5.25 GHz band. To obtain wide variable gain range, a p-type metal-oxide-semiconductor field-effect transistor (PMOS FET) in the low noise amplifier (LNA) section is connected in parallel. For a mixer, single balanced and folded structure is employed for low power consumption. Using this structure, the bias currents of the transconductance and switching stages in the mixer can be separated without using current bleeding path. The proposed front-end has a maximum gain of 33.2 dB with a variable gain range of 17 dB. The noise figure and third-order input intercept point (IIP3) are 4.8 dB and -8.5 dBm, respectively. For this operation, the proposed front-end consumes 7.1 mW at high gain mode, and 2.6 mW at low gain mode. The simulation results are performed using Cadence RF spectre with the Taiwan Semiconductor Manufacturing Company (TSMC) $0.18\;{\mu}m$ CMOS technology.)

• The Mathematical Education
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• v.50 no.2
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• pp.213-231
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• 2011

The purpose of this study is to analyze the 6th graders' understanding of the concepts of variable on various aspects of school algebra. For this purpose, the test of concepts of variable targeting a sixth-grade class was conducted and then two students were selected for in-depth interview. The level of mathematics achievement of the two students was not significantly different but there were differences between them in terms of understanding about the concepts of variable. The results obtained in this study are as follows: First, the students had little basic understanding of the variables and they had many cognitive difficulties with respect to the variables. Second, the students were familiar with only the symbol '${\Box}$' not the other letters nor symbols. Third, students comprehended the variable as generalizers imperfectly. Fourth, the students' skill of operations between letters was below expectations and there was the student who omitted the mathematical sign in letter expressions including the mathematical sign such as x+3. Fifth, the students lacked the ability to reason the patterns inductively and symbolize them using variables. Sixth, in connection with the variables in functional relationships, the students were more familiar with the potential and discrete variation than practical and continuous variation. On the basis of the results, this study gives several implications related to the early algebra education, especially the teaching methods of variables.

• Archives of design research
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• v.20 no.1 s.69
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• pp.21-32
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• 2007

To quantitatively measure or evaluate aesthetic factors is not easy in comparison with physical, functional, behavioral or economic factors. Yet aesthetic factors essentially play an important role in design modeling process. Despite its importance, research on aesthetic assessment or the interaction of aesthetic influential elements is insufficient. Therefore, this study is intended to find the relationships between visual preference and aesthetic variables of perceptual-cognitive dimension and affective dimension in commercial space design. According to the result of this substantiation research, aesthetic variables that give a positive effect on the preference of commercial space design are unity, order, and clarity in perceptual-cognitive dimension and 'pleasant', 'relaxing' in affective dimension. On the other side, aesthetic variables that give a negative effect on the preference are contrast, complexity, and ambiguity that is a contrary concept of clarity in perceptual-cognitive dimension and 'exciting', 'arousing' in affective dimension.

• Journal of Korean Elementary Science Education
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• v.33 no.4
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• pp.773-783
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• 2014

In National Curriculum of Science revised in 2007, the Free Inquiry was newly introduced to increase students' interest in science and to foster creativity by having students make their own question and find answer by themselves. The purpose of the study was to analyze characteristics, in cognitive domain, appeared in the processes of performing the Free Inquiry activities applying a brain-based evolutionary science teaching and learning principles. For this study, 106 fifth grade students participated, and they performed individually Free Inquiry activities. In order to characterize of the diversifying, estimating-evaluating-executing, and extending-applying activities in cognitive domain (C-DEF), the Free Inquiry diary constructed by the students, observations by a researcher, and interviews with the students were analyzed both quantitatively and qualitatively. The major results of this study were as follows: First, at C-D step, many students (71.5%) had difficulty in searching the meanings of their results and the contents of interpretations were at the level of simple description of their results. A few students (15.2%) derived interpretations based on causal relationships between specific variable and result. Also, the tendency that the numbers of interpretation about meaning of their results were increased as the scores of science attitude and achievement was appeared. Second, at C-E step, the students showed tendency of considering facts exactly explaining inquiry topic and being appliable to daily life rather than objectivity or accuracy of scientific knowledge. Third, at C-F step, there were three types of extension and application: simple repetition (8.2%), extension (64.0%), and upward application (17.6%) types. Based on these findings, implications for supporting appropriate interpretation, evaluation, and application of inquiry results are discussed.

• Korean Journal of Biological Psychiatry
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• v.11 no.2
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• pp.155-164
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• 2004

Objective:The present study examined the association between basic neurocognitive functions and emotional recognition in chronic schizophrenia. Furthermore, to Investigate cognitive variable related to emotion recognition in Schizophrenia. Methods:Forty eight patients from the Yongin Psychiatric Rehabilitation Center were evaluated for neurocognitive function, and Emotional Recognition Test which has four subscales finding emotional clue, discriminating emotions, understanding emotional context and emotional capacity. Measures of neurocognitive functioning were selected based on hypothesized relationships to perception of emotion. These measures included:1) Letter Number Sequencing Test, a measure of working memory;2) Word Fluency and Block Design, a measure of executive function;3) Hopkins Verbal Learning Test-Korean version, a measure of verbal memory;4) Digit Span, a measure of immediate memory;5) Span of Apprehension Task, a measure of early visual processing, visual scanning;6) Continuous Performance Test, a measure of sustained attention functioning. Correlation analyses between specific neurocognitive measures and emotional recognition test were made. To examine the degree to which neurocognitive performance predicting emotional recognition, hierarchical regression analyses were also made. Results:Working memory, and verbal memory were closely related with emotional discrimination. Working memory, Span of Apprehension and Digit Span were closely related with contextual recognition. Among cognitive measures, Span of Apprehension, Working memory, Digit Span were most important variables in predicting emotional capacity. Conclusion:These results are relevant considering that emotional information processing depends, in part, on the abilities to scan the context and to use immediate working memory. These results indicated that mul- tifaceted cognitive training program added with Emotional Recognition Task(Cognitive Behavioral Rehabilitation Therapy added with Emotional Management Program) are promising.

• Journal of Korean Academy of Nursing
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• v.29 no.3
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• pp.639-655
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• 1999

An explanatory design was employed to identify the relationship of physical, emotional & social readjustment and social support of post hospitalized stroke patients and their caregivers. A convenient sample of 254 patients who given follow-up care at the outpatient department after discharge and 225 caregivers were recruited. Mental Status Questionnaire (MSQ), Social Support Inventory Stroke Survivors (SSISS), Illness intrusiveness(II), Instument Activity of Daily Living(IADL), Center of Epidemilogic Studies-Depression(CES-D), social activity and caregiver burden were used for measurement in this study. Results showed patient's physical level measured by IADL and psychological level measured by depression were high. But social activity was low. Cognitive function, depression & social activity were not significantly different by the posthospitalized period, but IADL was. The source of professional support was mostly the physician at the outpatient department. The family support was found significantly related to patient's depression & social activity and caregiver's subjective burden. Professional support was found significantly related to patient's IADL & depression. Illness intrusiveness as a mediating variable was a sig nificantly predicting power on patient's IADL & depression. The path analysis was used to identify the variables to predict the physical, emotional, and social status of patients. As a result, patient's age, cognitive function, illness intursiveness and professional support significantly predicted the level of IADL ; patient's cognitive function, illness intrusiveness and family support significantly predicted the level of depression ; and patient's age and family support significantly predicted the level of social activity of posthospitalized stroke patients. Based upon these results, the rehabilitation programs to reduce the illness intrusiveness and improve cognitive funtion were recommended for the readjustment of the stroke patients. This model of the readjustment of the posthospitalized stroke patients is recommended as the framework for care of the stroke patients.

• 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.

• Fashion & Textile Research Journal
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• v.24 no.5
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• pp.567-576
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• 2022

This study aims to determine the effects of the experiences of ZEPETO platform users on their attitudes and purchase intentions. A survey on 10-20 Korean and Chinese virtual fashion consumers was conducted. Brand experiences were independent variables, and offline purchase was the dependent variable. The results showed that, first, among the four factors of the brand experience, Korea and China have the highest explanatory power. Second, the brand experience of Korean consumers significantly impacted their brand attitude. Additionally, cognitive and emotional experiences of the brand positively impacted their brand attitude. Third, the brand experience of Chinese consumers significantly affected their brand attitude, and among the sub-factors of brand experience, cognitive experience positively affected brand attitude. Fourth, the brand experience of Chinese consumers significantly influenced their offline purchase intention, and among the sub-factors of brand experience, cognitive experience positively influenced their offline purchase intention. Overall, an emotional branding strategy that provides brand and product information must be implemented for the Korean market encouraging consumers to develop a positive and emotional connection with the brand. The Chinese market would benefit from formulating a reliable branding strategy that easily provides a wide range of brand and product information focusing on cognitive experiences.

• Korean Journal of Audiology
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• v.25 no.4
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• pp.178-188
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• 2021

Background and Objectives: The influence of musical aptitude on cognitive test performance in musicians is a long-debated research question. Evidence points to the low performance of nonmusicians in visual and auditory cognitive tasks (working memory and attention) compared with musicians. This cannot be generalized to all nonmusicians, as a sub-group in this population can have innate musical abilities even without any formal musical training. The present study aimed to study the effect of musical aptitude on the working memory and selective attention. Subjects and Methods: Three groups of 20 individuals each (a total of 60 participants), including trained-musicians, nonmusicians with good musical aptitude, and nonmusicians with low musical aptitude, participated in the present study. Cognitive-based visual (Flanker's selective attention test) and auditory (working memory tests: backward digit span and operation span) tests were administered. Results: MANOVA (followed by ANOVA) revealed a benefit of musicianship and musical aptitude on backward digit span and Flanker's reaction time (p<0.05). Discriminant function analyses showed that the groups could be effectively (accuracy, 80%) segregated based on the backward digit span and Flanker's selective attention test. Trained musicians and nonmusicians with good musical aptitude were distinguished as one cluster and nonmusicians with low musical aptitude formed another cluster, hinting the role of musical aptitude in working memory and selective attention. Conclusions: Nonmusicians with good musical aptitude can have enhanced working memory and selective attention skills like musicians. Hence, caution is required when these individuals are included as controls in cognitive-based visual and auditory experiments.

• Journal of Audiology & Otology
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• v.25 no.4
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• pp.178-188
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• 2021

Background and Objectives: The influence of musical aptitude on cognitive test performance in musicians is a long-debated research question. Evidence points to the low performance of nonmusicians in visual and auditory cognitive tasks (working memory and attention) compared with musicians. This cannot be generalized to all nonmusicians, as a sub-group in this population can have innate musical abilities even without any formal musical training. The present study aimed to study the effect of musical aptitude on the working memory and selective attention. Subjects and Methods: Three groups of 20 individuals each (a total of 60 participants), including trained-musicians, nonmusicians with good musical aptitude, and nonmusicians with low musical aptitude, participated in the present study. Cognitive-based visual (Flanker's selective attention test) and auditory (working memory tests: backward digit span and operation span) tests were administered. Results: MANOVA (followed by ANOVA) revealed a benefit of musicianship and musical aptitude on backward digit span and Flanker's reaction time (p<0.05). Discriminant function analyses showed that the groups could be effectively (accuracy, 80%) segregated based on the backward digit span and Flanker's selective attention test. Trained musicians and nonmusicians with good musical aptitude were distinguished as one cluster and nonmusicians with low musical aptitude formed another cluster, hinting the role of musical aptitude in working memory and selective attention. Conclusions: Nonmusicians with good musical aptitude can have enhanced working memory and selective attention skills like musicians. Hence, caution is required when these individuals are included as controls in cognitive-based visual and auditory experiments.