• Korean Journal of Cognitive Science
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• v.22 no.1
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• pp.19-38
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• 2011

When quantitative representation and reasoning about space is difficult or impossible in a real world, we can use qualitative representation and reasoning. RCC-8 is a well-known qualitative method for 2D space. RCC-8, in which a basic ontological primitive entity for space is a region, shows the connection-based logics and the conceptual neighbors and transitions of topological status between two regions. The transitions happen by changing position or size of regions. However, more aspects have to be considered for representing and reasoning of the world. We propose a modified and extended method QSR-14 for qualitative spatial representation and reasoning of a dynamic physical 2D world in the gravitation field. We mention the need of a global reference frame and describe QSR-14 in detail for representing and reasoning of physical and chemical changes of a real world using the global reference frame. We believe QSR-14 is appropriate for the qualitative spatial representation and reasoning of a dynamic physical world. The usefulness of QSR-14 is shown with several examples.

• Journal of The Korean Association For Science Education
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• v.15 no.2
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• pp.185-193
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• 1995

The purpose of this article is to find out psychological mechanism on the core of misconceptions. Theoretical frame to search for the core of misconceptions is based on the Pascual-Leone's neo Piagetian theory. Although Pascual-Leone's theory is a cognitive developmental theory, its psychological mechanism gives us new insights on misconception. According to the comparison between Pascual-Leone's psychological mechanism and the common specifics of misconceptions and their items, conclusions could be summarized as follows: 1) Children's misconceptions and LC learning structures have the same nature. 2) Structures in items of misconceptions and misleading factor structures in cognitive tasks affect mental process with the same mechanism. 3) LC learning structures was activated preferentially in knowledge structures by F operator, with the same activation mechanism, the process children's misconceptions was activated firstly among other conceptions could be explained.

• Korean Journal of Cognitive Science
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• v.3 no.1
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• pp.1-24
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• 1991

This paper presents the Lexical Ambiguity Resolution System of Korean Language. This system uses Dependency grammar and Collative Semantics. Dependency grammar is used to analyze Korean syntactic dependency. A robust way to analyze a sentence is to establish links between individual words. Collative Semantics investigates the interplay between lexical ambiguity and semantics relations. Collative Semantics consists of sense-frame, semantic vector, collation, and screening. Our system was implemented by C programming language. This system analyzes sentences, discriminates the kinds of semantic relation between pairs of words senses in those sentences, and resolves lexical ambiguity.

• Korean Journal of Cognitive Science
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• v.3 no.1
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• pp.79-111
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• 1991

This paper suggests a system which analyzes facial images through hypotheses generation and verification.A model knowledge on faical structures is to be represented in a hieratchical frame system and the process of hypothesis generation and verification is to be embodied through linking upper lower-level frames.This paper especially addresses the problem of how to selec an approproate knowledge at each stage of hypotheses generation and verification.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.97-98
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• 2007

In this paper, we investigate the throughput capacity of a multi-hop relay network with cognitive radio (CR) enabled relay stations (RS). We suggested a TDMA/FDMA based frame structure where RSs dynamically select unused channels to communicate with the base station (BS) using CR techniques to analyze the throughput capacity. We developed the throughput capacity model for the proposed system based on utilization factor. The analytical results based on those equations show significant improvement in throughput capacity for CR enabled multi-hop relay system.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.05a
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• pp.219-222
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• 2009

Rapid object recognition is one of the main stream research themes focusing to reveal how human recognizes object and interacts with environment in natural world. This field of study is of consequence in that it is highly important in evolutionary perspective to quickly see the external objects and judge their characteristics to plan future reactions. In this study, we investigated how human detect natural scene objects and categorize them in a limited time frame. We applied Magnetoencepahlogram (MEG) while participants were performing detection (e.g. object vs. texture) or basic-level categorization (e.g. cars vs. dogs) tasks to track the dynamic interaction in human brain for rapid object recognition process. The results revealed that detection and categorization involves different temporal and functional connections that correlated for the successful recognition process as a whole. These results imply that dynamics in the brain are important for our interaction with environment. The implication from this study can be further extended to investigate the effect of subconscious emotional factors on the dynamics of brain interactions during the rapid recognition process.

• Journal of Advanced Navigation Technology
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• v.17 no.5
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• pp.506-515
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• 2013

In cognitive radio networks, several research works typically address the framework which consists of a spectrum sensing period and a data transmission period. When the frame period is short, there is the problem that the throughput of secondary users decrease. In this paper, aggregated data slot structure is considered to increase the throughput of secondary users. Chapman-Kolmogorov equation is used for the modeling of the transmission probability of primary users and formulation of an optimization problem to maximize the throughput of secondary users. Solution of the optimization problem results in the optimal spectrum sensing time, the length of data slot and the number of data slots governed by a spectrum sensing.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.3A
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• pp.235-243
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• 2009

In this paper, we investigate the cognitive and cooperative communication scheme to improve the spectral efficiency in multiuser OFDMA systems using wireless relays. First, we propose the frame structure in which the efficient frequency reuse scheme with the cognitive technique is performed to increase the system throughput. And in the case where the THP (Tomlinson-Harashima preceding) is used for the elimination of interference from the relay, we derive the effective signal to noise ratio of the link largely affected by the channel quantization error. From the system level simulation results, it is shown that the proposed cognitive and cooperative communication scheme increases the overall system performance including the feedback overhead.

• 한국노년학
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• v.30 no.1
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• pp.127-140
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• 2010

This study aims to understand the effects of a Computer - based Cognitive Rehabilitation Therapy(CBCRT) evidence based on mild dementia patients' ability to activities daily living(ADL), cognitive function and measure of occupational performance and to suggest basic data for a cognitive rehabilitation therapy for dementia patients. Method : A CBCRT was applied two times a week for 5 weeks to 14 mild dementia patients who visited Yongin Center for Managing Dementia in Gyeongi-do between February and August 2009. Based on frame of reference for Visual-Perception a CBCRT was applied at home. Moreover, a one group pretest-post test design was, which is a quasi-experiment and research, also applied in order to verify the effects of the rehabilitation therapy on the subjects' ability to ADL, cognitive function and occupational performance skills. Results: A significant effect was confirmed (p<.05) from the CBCRT which Assessment of Motor and Process Skills(AMPS) processing skills and cognitive function and occupational performance skills. Neither was found any significant effect in improving motor skills from AMPS. Conclusion: It seems that a CBCRT based on evidence and has an effect on the improvement of the ability to ADL and cognitive function of mild dementia patients living in a community. The present author hopes that, in the future, more cognitive rehabilitation programs will be developed to improve the functions of mild dementia patients living in a community.

• Journal of Educational Research in Mathematics
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• v.9 no.1
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• pp.51-80
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• 1999

The paper reviews of the constructivist view of mathematics and mathematics education. First of all, we shall study how mathematics has been treated as an object of cognition in philosophy or cognitive theories, what is changed in modern mathematics. It can lead us to understand the constructivist perspective on mathematics. Secondly, we will examine the view, the teaching and learning principles of mathematics education based on constructivism. Didactic transposition theory will be used as a frame of reference for this examination.