• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.9
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• pp.3004-3015
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• 2014

This letter proposes an efficient joint resource allocation scheme for OFDM-based cooperative cognitive radio networks (CRNs) under various practical limitations. Compared with those traditional approaches, which guarantee the transmission rates of cognitive users, the proposed scheme ensures that cognitive users are maintained in proportion to the predefined target rates. Numerical simulation shows that the proposed scheme can achieve a reasonable tradeoff between performance and computational complexity.

• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.1
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• pp.25-32
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• 2018

Purpose: This study was conducted to figure out the cognitive characteristics of the elderly living in apartment complex in order to construct basic data for the design of sustainable and age friendly apartment area. Methods: Cognitive map was used to identify and analyze the elderly residents' status of residential environment cognitions. The elderly living in Gongreung-dong apartment was randomly interviewed outdoor area and requested to draw cognitive maps on their living environment. 26 valid cognitive maps collected were analyzed, classified into two different types: Line type and Dot type. The average age, cognitive distance, length of residence, number of elements in the map(complexity) were then compared by Line and Dot type, as well as by gender. Correlations among variables also were analysed. Results: Males showed a tendency to draw dot types, which means they are place-centered, and females drew line types more than males, which means they are way-centered. The average cognitive distance of male group was greater than that of female group. As the age went up, the number of perceived place and the cognitive distance decreased. Oder people tended to draw line types rather than dot types. As the cognitive distance was longer, the perceived place and the number of lines increased. Implications: The age was more related to the recognition of the residential environment. The younger the residents were, the more they recognized the elements. The points that were represented by dots in the cognitive maps are places for memories for the individuals. Creating more memorable spaces will affect the cognition of residents on living environment. It is better to improve the cognitive environments before cognitive abilities of residents decrease.

• Korean Institute of Interior Design Journal
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• v.15 no.3 s.56
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• pp.173-183
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• 2006

Design is inseparably related to aesthetics. In spite of that, it is difficult to explain the precise aesthetic variables that affect the aesthetic value of space or environment. Therefore, this study intended to find the relationships between aesthetic variables by perceptual and affective judgement for space design with focus on complexity and preference variables. The research found low level of 'arousing' as well as high levels of affective dimension variables 'pleasant' and 'relaxing' evoked high preference. High preference also appeared in space design cases with high unity, order, and clarity with low contrast and complexity, which are variables of perceptual dimension. Complexity, one variables of preference by Kaplan, is in an inverse proportion to space preference. Thus, space design with high complexity has high level of 'exciting' and 'arousing' affective responses and relatively low level of 'relaxing' response. Additionally, it was confirmed that the most importantly influential factor on complexity was diverse components rather than visual richness and ornamentation.

• Journal of Communications and Networks
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• v.11 no.2
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• pp.148-156
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• 2009

The fixed spectrum assignment policy in today's wireless networks leads to inefficient spectrum usage. Cognitive radio network is a new communication paradigm that enables the unlicensed users to opportunistically use the spatio-temporally unoccupied portions of the spectrum, and hence realizing a dynamic spectrum access (DSA) methodology. Interference temperature model proposed by Federal Communications Commission (FCC) permits the unlicensed users to utilize the licensed frequencies simultaneously with the primary users provided that they adhere to the interference temperature constraints. In this paper, we formulate two NP-hard optimal scheduling methods that meet the interference temperature constraints for cognitive radio networks. The first one maximizes the network throughput, whereas the second one minimizes the scheduling delay. Furthermore, we also propose suboptimal schedulers with linear complexity, referred to as maximum frequency selection (MFS) and probabilistic frequency selection (PFS). We simulate the throughput and delay performance of the optimal as well as the suboptimal schedulers for varying number of cognitive nodes, number of primary neighbors for each cognitive node, and interference temperature limits for the frequencies. We also evaluate the performance of our proposed schedulers under both additive white gaussian noise (AWGN) channels and Gilbert-Elliot fading channels.

• Archives of design research
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• v.21
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• pp.1-12
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• 1997

This research is that it could use a theory from a .cognitive science, making a hypothesis to explain the thingking steps of designing, adapting the problem solving of the design from knowledge of a cognitive science, to meet the possiblity which it can be developed the new way of the thinking. Design is a field where it needs a complexity with hi-brain activities. And cognitive science is a science which it study human brain activities. However, it is also quite possible to bo adaped over all design by linking with design and cognitive science. I explaned the ideation of the thinking steps on this study by the knowledge of cognitive science, to observe to be possible. I found out the new ways of possibilities from design thinking process. It is a result that I've been interpretated the design process and the thinking process out of the theory of knowledge structure.

• Korean Journal of Child Studies
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• v.9 no.2
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• pp.133-156
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• 1988

This study investigated developmental change with reference to continuity theory in the acquisition of concepts of kin relation, task difficulty with reference to cognitive complexity, and interrelationships in the performance of cognitive tasks of kinship concepts with reference to cognitive parallelism. The subjects consisted of 6-, 8-, 10, and 12-year-old randomly selected children attending kindergartens or elementary schools in Seoul. The schools were located in various residental areas regarded as either middle or lower class. The 81 boys and 80 girls participated in 3 experiments on classification, seriation, and grouping. The instrument for the classification, seriation, and grouping tasks was composed of 10 10cm black on white line drawings of the head and upper torso area of persons in kin relationship. The data was analyzed with MANOVA. A significant age effect was found in the 3 quasi- experiments. There were significant effects on task difficulty. The biosocial power distribution indirectly influenced children's acquisition of kin relational concepts; that is, children performed better in male-kin than in female-kin tasks. There was a high correlation in performance between the 3 cognitive tasks. These findings support the continuity theory (except for seriation), a model which arranges kin-names in order of cognitive load, the centric status of men in society, and the theory of cognitive developmental parallelism.

• Korean Journal of Cognitive Science
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• v.30 no.3
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• pp.105-132
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• 2019

This study quantitatively analyzed the speeches of the former 8 Presidents of the Republic of Korea. Unlike the previous studies, this study analyzed both the content word and the functional word related to the psychological phenomenon. In Study 1, six language style indicators such as clout, authenticity, presidentiality, cognitive complexity, femininity, and psychological health were developed. Also, as presidential speeches have been made recently, authenticity, presidentiality, psychological health tended to increase, but cognitive complexity tended to decrease. These tendencies were supported by linear trend analysis. The linguistic differences were distinct not only among individual presidents but also by groups based on the political orientation of the president. In the progressive presidential speech, more clout, cognitive complexity, femininity were observed. In contrast, more authenticity and presidentiality were observed in the conservative presidential speech. In Study 2, it was demonstrated whether the developed language style indicators show reliability in the most recent President's speeches. Finally, it was discussed that the relationship between language style indicators, fitness of the political tendency between the regime and the general public since 2000s, and the characteristics of femininity indicator.

• Journal of the Korean housing association
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• v.23 no.5
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• pp.19-29
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• 2012

It is very necessary to know about child recognition of residential environment to plan and design an environment proper for children's growth and development. The research method using Cognitive Map, which may be defined as "an overall mental image of representation of the space and layout of a setting" can be a good tool for studying child recognition of residential environment. This study analyzed the child recognition of the size of home range, the number of residential environment elements, the types of Cognitive Map and the levels of Cognitive Map to understand the contents of child recognition about their residential environment. Subjects were 206 children in age6, 8 and 10 in Gwanju and Jeonnam area. As the result of the study, we found that 70% of child recognized 100~500 M as the size of home range, and that the number of the elements of residential environment was 7, average. And we also found that sequential map was more popular than spatial map in child's Cognitive Map type and that almost 60% of child respondents drew the Cognitive Map of level 1 complexity type. As the result of this study, we could know that the research method using Cognitive Map was very useful for understanding the child recognition of residential environment.

• Korean Journal of Cognitive Science
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• v.34 no.1
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• pp.1-20
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• 2023

In this study, we examined the effects of spatial attention in Hangul word recognition depending on visual factors. The visual complexity of words (Experiment 1) and contrast (Experiment 2) were manipulated to examine whether the effect of spatial attention differs depending on visual quality. Participants responded to words with and without codas in experiment 1 and words in high-contrast and low-contrast conditions in experiment 2. The effects of spatial attention were investigated by calculating the difference in performance between the condition where spatial cues were given at the target location (valid trial) and the condition where the spatial cues were not given at the target location (invalid trial) as the cuing effects. As a result, the cuing effects were similar depending on the complexity of the words. It indicates that the effects of spatial attention were not different across the visual complexity conditions. The cuing effects were greater in the low-contrast condition than in the high-contrast condition. The greater effect of spatial attention when the contrast is low was explained as a mechanism of signal enhancement.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.585-586
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• 2004