• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권9호
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• pp.4372-4389
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• 2019

Spectrum sensing has attracted much attention due to its significant contribution to idle spectrum detection in Cognitive Radio Networks. However, specialized discussion is on complexity-based sensing strategy for spectrum sensing seldom considered. Motivated by this, this paper is devoted to complexity-based sensing strategy for spectrum sensing. Firstly, three efficiency functions are defined to estimate sensing efficiency of a spectrum scheme. Then a novel sensing strategy is proposed given sensing performance and computational complexity. After that, the proposed sensing strategy is extended to energy detector, Cyclostationary feature detector, covariance matrix detector and cooperative spectrum detector. The proposed sensing strategy provides a novel insight into sensing performance estimation for its consideration of both sensing capacity and sensing complexity. Simulations analyze three efficiency functions and optimal sensing strategy of energy detector, Cyclostationary feature detector and covariance matrix detector.

• 한국과학교육학회지
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• 제31권6호
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• pp.958-969
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• 2011

본 연구의 목적은 과학영역에서의 자기효능감, 과학성취, 인지적 자기조절학습전략의 관계를 살펴보는데 있다. 설문지를 통해 수집된 초등학교 5학년 158명의 자료가 최종 분석되었다. 학생들의 과학관련 자기효능감과 인지적 자기조절학습전략(시연, 정교화, 조직화, 초인지)이 측정되었고 과학성적이 수집되었다. 기초통계분석으로 상관분석과 회귀분석을 사용하였고 매개효과 검증을 위해 Baron과 Kenny(1986)의 검증방법과 구조방정식모형분석이 사용되었다. 매개 효과가 있을 경우 이를 검증하기 위해 Sobel test가 실시되었다. 연구결과 인지적 자기조절학습전략은 과학성적을 예측하는 중요한 요인이었으며 과학영역관련 자기효능감 역시 과학성적을 예측하는 중요한 심리적 구인임이 검증되었다. 매개효과검증 결과 인지적 자기조절학습전략은 자기효능감과 학업성취의 관계에 있어 부분매개자의 역할을 하는 것으로 나타났다. 하위요인별 분석결과 시연전략은 자기효능감과 학업성취의 관계에서 매개자의 역할을 하지 않았다. 본 연구결과를 기반으로 학생들의 과학성취를 향상시키기 위한 교육적 제언을 하였다.

• 한국과학교육학회지
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• 제24권4호
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• pp.687-708
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• 2004

The purpose of this study is to investigate the relationships between cognitive conflict and students' causal attributions and to find out what kinds of attributions affect successful resolution of cognitive conflict in learning physics. Twenty-nine college students who attended a base general physics course took an attribution test and a conceptual pretest related to action and reaction concept. Of these, twenty students who revealed alternative conceptions were selected. They were confronted with a discrepant demonstration and took part in the cognitive conflict level test, a posttest, and delayed posttest. Those students who experienced high levels of cognitive conflict were selected and interviewed to find out what kinds of attributions affect resolving the conflict. When confronted with the discrepant event, the students who attributed success outcomes to "effort" experienced higher levels of cognitive conflict than those to "task difficulty." However, those students who revealed high levels of cognitive conflict and attributed success outcomes to effort did not always produce conceptual change. They had different perspectives on effort and conducted different effort activities to resolve the cognitive conflict. In addition, these effort activities appeared to include their motivational beliefs, metacognitive and volitional strategies. The results of this study indicate that in order for the conflicts to lead to change, students need to have the perspective on effort implying the use of the self-regulated learning strategy and to conduct effort activities based on them. Beyond cold conceptual change, this article suggests that there is a management strategy of cognitive conflict in the classroom context.

• 감성과학
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• 제7권2호
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• pp.163-178
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• 2004

본 연구에서는 수행된 과제와 독립적인 인지과정에서의 개인차와 관계가 있는 인지양식의 차원들을 규명하였고 과제와는 독립적인 인지과정에 대한 Robertson(1985)의 이론을 지지하는 결과를 보여주었다. 각 개인의 초기 인지전략은 다른 과제를 수행해 가는 동안 계속해서 유지되는 것으로 관찰되었고 결국 그것이 그들의 인지양식으로 간주되었다. 그렇지만 개인들의 인지양식은 많은 수행을 거치면서 그 과제들과의 상호작용을 통해 변화하여 그 과제에 특정한 전략을 이끌어낼 수도 있다는 점을 시사하였다.

• 보건의료산업학회지
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• 제10권3호
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• pp.75-84
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• 2016

Objectives : The aim of this study was to compare a treatment focusing on the physical function to an intervention focusing on a cognitive strategy in stroke patients which improves their performance skills of daily activities. Methods : This study design was a randomized control trial selecting 43 people with stroke patients. This study consisted of a control group, which received conventional occupational therapy focusing on physical function, and an experimental group which was trained to develop a cognitive strategy by themselves. Both groups each received 10 sessions of the treatment. This study compared the skills for performing daily activities before and after the intervention and analyzed the data with SPSS Ver. 18.0. Results : This study showed a significant improvement in all performance skills in the experimental group (p<.05). There was no statistically significant difference in the performance skills before and after the intervention in the control group (p>.05). Conclusions : It was verified that stroke patients to develop a cognitive strategy by themselves is more effective than to improve the physical function in performance skills for daily activities.

• 디지털콘텐츠학회 논문지
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• 제11권2호
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• pp.153-160
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• 2010

본 연구는 멀티미디어 활용학습에 있어서, 인지양식(장의존/장독립), 연령(만5세/만8세/만12세), 정교화전략적용유무(전문/요약문)에 따른 학습효과차이를 검증하는데 목적을 두었다. 연구결과, 정교화전략은 연령이 높은 아동(만12세)에게만 효과적인 것으로 나타났다. 또한, 인지양식에 따른 정교화전략의 효과차이도 없는 것으로 나타나, 아동의 멀티미디어 학습에 있어서 정교화전략의 적용 시에는 연령이 중요한 변수로 고려되어야 함을 알 수 있다.

• 한국항공운항학회지
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• 제26권1호
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• pp.10-24
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• 2018

This paper tried to analyze the response of air traffic controller(ATC) against abnormal situations using survey based on cognitive strategies suggested by Malakis et al.(2010). The survey designed to empirically analyze the effect of the cognitive strategy factors on organizational effectiveness. The main purpose of this research was as follows: First, it was analyzed both the individual-scale and team-scale factors which constructed the cognitive strategy against abnormal situations. Secondly, how seriously impact the ATC's cognitive strategies on their organizational effectiveness. The organizational effectiveness was divided into such two latent variables as job absorption and job satisfaction. According to the a analysis, it was proven that premeditated act of ATC had a positive significant effect on team-scale cognitive strategies such as teamwork, communication and error management. Moreover, it was found out the team-scale cognitive strategies had also a positive significant effect on job absorption. On the other hands, individual-scale cognitive strategies had no or negative effect on job absorption. Job absorption was proven to have a significant effect on job satisfaction of ATC.

• 영어어문교육
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• 제11권4호
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• pp.21-47
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• 2005

The purpose of this study is to investigate the effectiveness of English vocabulary learning strategies such as definition-oriented/contextoriented/situated context-oriented vocabulary learning strategy according to the cognitive styles of learners and interaction effect on the achievement test score between the learners' cognitive style and vocabulary learning strategies. The results show that there is no significant difference in the achievement test scores between field-dependent learner group and field-independent learner group. And there is significant difference in the English vocabulary achievement test scores among three experimental treatment groups, definition-oriented, context-oriented, situated context-oriented vocabulary learning strategy groups. Finally, there is an interaction effect on the achievement test score between the learners' cognitive style and vocabulary learning strategies.

• 한국식품조리과학회지
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• 제32권6호
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• pp.734-744
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• 2016

Purpose: This study investigated the preference and awareness of consumers residing in the capital area with respect to South and North Korean regional cuisine to provide baseline data for developing effective commercialization strategies. Methods: This survey was conducted among adults over the age of 19 years who were residing in Seoul and Gyeonggi province area, and data analysis was performed using SPSS WIN 18.0. Results: Analysis of the survey participants' preference for South and North Korean regional cuisine showed that Hwanghae province had the highest preference by $4.35{\pm}1.72$ points, whereas Gangwon province had the lowest preference by $3.75{\pm}0.66$ points. Factorial analysis on general characteristics of Korean regional cuisine resulted in 2 factors - 'locality' and 'health'. Cluster analysis showed that participants could be sorted into two clusters by their awareness of Korean regional cuisine - 'the lower cognitive group' and 'the higher cognitive group'. Cluster analysis on the tourism commercialization strategy for Korean regional cuisines showed that 'the higher cognitive group' had significantly higher awareness regarding the following 3 items: 'merchandising strategy', 'popularization strategy' and 'marketing strategy' (p<0.001). Cluster analysis of the world commercialization strategy showed that 'the higher cognitive group' had significantly higher awareness regarding all items of the 'R&D support strategy' and 'Food culture promotion strategy' categories than the 'the lower cognitive group' (p<0.01). Conclusion: Popularization strategies such as value perception based on the well-being concept, and standardization of recipes; merchandising strategies based on storytelling; and food and culture promotional strategies such as Korean cooking classes and food tasting events, were rated as effective commercialization strategies to increase the popularity of Korean regional cuisine.

• 우울조울병
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• 제9권2호
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• pp.78-86
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• 2011

Objectives : The aim of this study was to investigate relationship between perceived stress level, cognitive emotion regulation (CER) strategy and hope in group with high depressive symptom and higher-level perceived stress (H-H) and group with high depressive symptom and lower-level perceived stress (H-L) in patients with depression. Method : A total of 85 patients (over score of 16 by Beck depression Inventory; BDI) were surveyed with Cognitive emotion regulation questionnaire (CERQ), Perceived stress scale (PSS), and The state hope scale (SHS). Mean scores of CERQ and SHS were compared between relatively higher perceived stress and lower perceived stress groups. Correlation analysis and multiple linear regression analyses were performed to identify the effect of BDI, PSS and CER strategy on SHS in two groups. Results : In ANOVA, the level of hope and maladaptive CERQ score proved to be significantly lower among the H-H group than among the H-L group, while adaptive CERQ scores were not. In Regression analysis, the effective CER strategy in SHS were 'Refocus on planning' in H-H group, while it was 'Acceptance' CER strategy in H-L group. The final regression model explained 36% of the variance of SHS in H-H group and explained 21% of SHS in H-L group. Conclusion : These findings suggest that 'Refocus on planning' and 'Acceptance' cognitive emotion strategy are helpful in promotion of state hope on depression. Especially, 'Refocus on planning' strategy is more effective in high depressive symptom and high-perceived stress level, while 'Acceptance' strategy help to promote hope in high depressive symptom and low-perceived stress level in patients with depression.