• The Journal of Korean Institute of Communications and Information Sciences
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• 제33권9A호
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• pp.853-866
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• 2008

In this paper, a multi-hop relaying transmission scheme is analyzed regarding its feasibility and potentiality in the IEEE 802.22-based cognitive radio (CR) environment. Shortly, basic design issues are addressed such as relay station (RS) deployment and a frame structure of physical channel to escape inter-hop interference. This paper mainly develops a radio resource management scheme based on spectrum sensing results aggregated from CR secondary nodes and improves the opportunistic spectrum sharing efficiency. In particular, a decision rule about a channel availability is made using a distributed sensing method. Subsequently, spectrum allocation and routing path decision procedures are proposed to establish a link from source to destination with a hop-by-hop manner. Simulation results show that the proposed multi-hop relaying scheme is substantially profitable in CR environments if the number of hops and RS deployment are designed in such a way that the spectrum sharing gain is larger than spectrum division loss which is inherently induced in multi-hop relaying systems.

• Korean Journal of Cognitive Science
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• 제23권2호
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• pp.185-204
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• 2012

A three factor experiment was conducted to explore the effects of giving prompts and asking for self explanation and the modulating effect of the need for cognition (NC) on the two interventions. The effects of giving prompts and asking for self explanation were different depending on the task and the level of need for cognition. Participants of low NC conditions showed the prompt effect and the self explanation effect in the memory tests. On the other hand, participants in the high NC conditions performed better in the comprehension test when they were given prompts and were asked to self explain. However, high NC participants performed worse when they were asked to self explain without providing the prompts. The results were interpreted to suggest the importance of detecting the right parts in getting the self explanation effect.

• Korean Journal of Cognitive Science
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• 제14권3호
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• pp.13-21
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• 2003

This study presents a design of Teachable Agent(TA) and its theoretical background. TA is an intelligent agent to which students as tutors teach, pose questions, and provide feedbacks using a concept map. TA consists of four independent Modules, Teach Module, Q&A Module, Test Module, and Resource Module. In Teach Module, students teach TA by constructing concept map. In Q&A Module, both students and TA ask questions and answer questions each other through an interactive window. To assess TA's knowledge and provide feedback to students, Test Module consists of a set of predetermined questions which TA should pass. From Resource Module, students can search and look up important information to teach, ask questions, and provide feedbacks whenever they want. It is expected that TA should provide student tutors with an active role in learning and positive attitude toward the subject matter by enhancing their cognition as well as motivation.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제39C권12호
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• pp.1280-1288
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• 2014

In this paper, we use the ECMA-392 standard, the first cognitive radio networks to meet the demand for IT services in the ship. First, we learn about ECMA-392-based network and examine the consideration and the problems for assigning channels to the device. And, we propose a fair channel resource allocation to ensure efficiently channel required by device groups in ECMA-392 MAC protocol. This is a method to reallocate the channels fairly with considering the channel assignment parameters to a new device group and existing device groups. The simulation results show that the proposed scheme improves throughputs compared to the existing one.

• Journal of Korean Library and Information Science Society
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• 제42권2호
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• pp.215-236
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• 2011

I studied on the relations of constructivism and school library assisted instruction in this paper. Constructivism is the most important goal of the modern schooling. In constructivism they insist that knowledge is constructed by the learner individually and subjectively. So in constructivism they focus their attention on setting authentic environment of learning for each individual learner. Constructivism was developed into the learner-centered instruction in schooling nowadays. In constructivism the following instructions are very important for achievement its' goal ; problem based learning, project based learning, discussion based learning etc. These instructions are supported commonly by resource based learning. Educational resources are managed in school library totally. School library assisted instruction is the most effective one for resource based learning. And information literacy instruction by teacher librarian relates closely meta cognitive learning of reflections in constructivism. School library assisted instruction is the essential element for the practice of constructivism in schooling.

• Archives of design research
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• 제15권3호
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• pp.157-166
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• 2002

This research verified advertising effect according to ad information format and layout based on resource-matching theory. Existing researches suggested inconsistent results that it's effective to design advertising easy to understand by using factual information presentation and integrated layout or it's effective do design difficult advertising to understand by using explanatory information presestation and separate layout. The result of this study suggest that advertising effect by advertising design style is different according to situational elements such as motivation level of information processing and brand hierarchy. The results show that, in the high prestige brand, easily designed advertising using factual information presentation and integrated layout is more effective because consumers make favorable inference by remained cognitive resources. Contrary to this in the low prestige brand, not easily designed advertising using explanatory information and separate layout is more effective because consumers have no remained cognitive resources so that they concentrate on advertising itself.

• Journal of The Korean Association of Information Education
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• 제22권6호
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• pp.711-721
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• 2018

The development of artificial intelligence technology and the shift to a software-driven society are raising the need for digital literacy education on how to access, understand, use, create and share new open content in a variety of sustainable open content. At this point in time, this paper defines the digital literacy as the subliteracy concept for data, tools, and device elements. It is defined as a concept that includes cognitive and non-cognitive abilities and is stratified by computer literacy, ICT literacy, and information literacy. Open content is also defined as teaching-learning materials that can be used and shared freely by anyone, such as the Open Education Resource (OER) and the Open Access movement. Based on the two definitions, a three-step strategy for digital literacy education was developed to select open content in the digital environment, followed by a digital literacy education plan, and finally, an education frame to foster digital literacy capabilities.

• Korean Journal of Cognitive Science
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• 제27권1호
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• pp.101-127
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• 2016

The present study was conducted to examine the effect of meta-cognitive strategy and transfer appropriate processing(TAP) on prospective memory performance. In two experiments, encoding strategy for PM target words was manipulated by instructions. Participants who were assigned to meta strategic condition were engaged to rate task difficulty(EOL) in addition to predict their own performance(JOL), while participants in cognitive strategy condition were to remember target words by pleasantness ratings and sentence generation. In experiment1 and experiment 2, all participants in both conditions performed not only TAP ongoing task but also TIP ongoing task. Results revealed the benefit of meta cognition and transfer appropriate processing on PM performance. Furthermore, the benefit of TAP was diminished in cognitive strategy condition. There were no-costs on judgement tasks across conditions. The findings suggest that meta-cognition allows to sustain PM targets and intention without regard to cognitive resource.

• The Journal of the Korea Contents Association
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• 제16권5호
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• pp.242-250
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• 2016

This study was conducted to investigate whether Stroop-related cognitive task will be affected according to the preceding affective valence factored by matchedness in response time(RT) and whether facial recognition will be indexed by specific event-related potentials(ERPs) signature in normal person as in patients suffering from affective disorder. ERPs primed by subliminal(30ms) facial stimuli were recorded when presented with four pairs of affect(positive or negative) and cognitive task(matched or mismatched) to get ERP effects(N2 and P300) in terms of its amplitude and peak latency variations. Behavioral response analysis based on RTs confirmed that subliminal affective stimuli primed the target processing in all affective condition except for the neutral stimulus. Additional results for the ERPs performed in the negative affect with mismatched condition reached significance of emotional-face specificity named N2 showing more amplitude and delayed peak latency compared to the positive counterpart. Furthermore the condition shows more positive amplitude and earlier peak latency of P300 effect denoting cognitive closure than the corresponding positive affect condition. These results are suggested to reflect that negative affect stimulus in subliminal level is automatically inhibited such that this effect had influence on accelerating detection of the affect and facilitating response allowing adequate reallocation of attentional resources. The functional and cognitive significance with these findings was implied in terms of subliminal effect and affect-related recognition modulating the cognitive tasks.

• Journal of Life Science
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• 제26권1호
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• pp.129-139
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• 2016

Exercise increases the expression and interaction of major neurotrophic factors such as brain-derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1), and vascular endothelial growth factor (VEGF) at both central and peripheral tissues, which contributes to improved brain and neural plasticity and cognitive function. Previous findings have been to understand the effect of light or moderate intensity aerobic exercise on neurotrophic factors and cognitive function, not that of high intensity aerobic exercise. However, recent findings suggest that high intensity interval training is a safe, less time-consuming, efficient way to improve cardiorespiratory fitness and weight control, thus American College of Sport Medicine (ACSM)’s guidelines for exercise prescription for various adult populations also recommend the application of high intensity interval training to promote their overall health. High intensity interval training also enhances the expression of BDNF, IGF-1, and VEGF at the brain and peripheral tissues, which improves cognitive function. Increased frequency of intermittent hypoxia and increased usage of lactate as a supplementary metabolic resource at the brain and neural components are considered a putative physiological mechanism by which high intensity interval training improves neurotrophic factors and cognitive function. Therefore, future studies are required to understand how increased hypoxia and lactate usage leads to the improvement of neurotrophic factors and what the related biological mechanisms are. In addition, by comparing with the iso-caloric moderate continuous exercise, the superiority of high intensity interval training on the expression of neurotrophic factors and cognitive function should be demonstrated by associated future studies.