• Journal of Biomedical Engineering Research
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• v.9 no.1
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• pp.135-138
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• 1988

In this paper, computerized BEAM was implemented for the space domain analysis of EEG. Trans-formation from temporal summation to two-dimensional mappings is formed by 4 nearest point inter-polaton method. Methods of representation of BEAM are two. One is dot density method which classify brain electrical potential 9 levels by dot density of gray levels and the other is colour method which classify brain electrical 12 levels by red-green colours. In this BEAM, instantaneous change and average energy distribution over any arbitrary time interval of brain electrical activity could be observed and analyzed easily. In the frequency domain, the distribution of energy spectrum of a special band can easily be distinguished normality and abnormality.

• Communications of Mathematical Education
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• v.24 no.2
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• pp.475-502
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• 2010

In this paper, the ability to use mathematical representations in solving math problem was analyzed according to student assessment levels using 113 first-year high school students, and the characteristics of their representation usage according to student assessment levels were also examined. For this purpose, problems were presented that could be solved using various mathematical representations, and the students were asked to solve them using a maximum of three different methods. Also, based on the comparative analysis results of a paper evaluation, six students were selected and interviewed, and the reasons for their representation usage differences were analyzed according to their student assessment levels. The results of the analysis show that over 50% of high ranking students used two or more representations in all questions to solve problems, but with middle ranking students, there were deviations depending on the difficulty of the questions. Low ranking students failed to use representation in diverse ways when solving problems. As for characteristics of symbol usage, high ranking students preferred using formulas and used mathematical representations efficiently while solving problems. In contrast, middle and low ranking students mostly used tables or pictures. Even when using the same representations, high ranking students' representations were expressed in a more structurally refined manner than those by middle and low ranking students.

• Journal of Elementary Mathematics Education in Korea
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• v.16 no.3
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• pp.427-450
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• 2012

Using representations is essential for students to organize their thinking, to solve problems and to communicate each other. Students express information or situations suggested by problems easily and organize and infer them systematically using representations. Also, teachers are able to comprehend students' levels of understanding and thinking process better through them, and influence their representations. This study was conducted to understand mathematical representations of students uprightly and to seek implications for proper teaching of representations, by analyzing representations of students in mathematical problem solving process and the transformation process of representation via interactions.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.11
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• pp.125-134
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• 2018

This study examines Dalibor Vesely's theoretical proposition of communicative space and tries to develop it through a review of the contemporary architectural case. Vesely poses a critical question about communication: how do the situational conditions of our everyday life and the spatial characteristics of the natural world in which we live communicate through representation. He emphasizes the spatial and situational conditions and the role of representation in communication, arguing that architecture should create the formation of communicative space to restore its primary role as the corporeal foundation of culture. This study thus focuses on one of the critical concepts of his theory: "the communicative movement," which is, according to him, ontological and situational because it animates and transforms human circumstances as a whole. Further, it pursues some practical knowledge of creating the communicative space, by examining the design theory and practice of Zaha Hadid, who thematizes communication and movement in her architectural approach. This study analyses the different levels of representation and modes of movement in her architectural space to reveal the possibilities and limits of its communicative roles. We will find that the representation of Hadid's architectural space is not the formal representation of reality, but a mathematical and projective representation of abstract concepts. Despite its apparent aesthetic consistency, the inward and self-referential relation between the individual elements of the architectural space reveals its limit for the communicative space.

• Korean Journal of Child Studies
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• v.34 no.6
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• pp.139-158
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• 2013

Karmiloff-Smith was first to propose the 'Representational Redescription model'. It describes a process through which children elaborate their knowledge from the unconscious and implicit levels to the conscious and explicit levels. The model also assumes that children in perfectly explicit levels are able to express their own representation of knowledge verbally. This study was conducted to investigate Karmiloff-Smith's Representational Redescription(RR) model(1990, 1992, 1999) within the drawing domain. Additionally, how verbalization training influences children's development of representational redescription in drawing were also examined. First, 331 children (4- to 6-year-olds and an older comparison group of 7- to 9-year-olds) were asked to create six drawings of both familiar and novel topics. From these drawings, children were measured for procedural rigidity and developmental differences. Thereafter 80 5-year-olds children who were not able to manipulate their drawings with flexibility were selected. They were divided into an experimental group and two control groups. A group of verbalization training was given a session using 5 tasks. Compared to the control groups, children who practiced verbalization in the training group showed more advanced levels of representation than their previous levels in the pretest. The results were interpreted as meaning that verbalization is likely to facilitate children's reorganization of implicit knowledge within the drawing domain and to transfer this toward explicit forms. Further research needs to pay more attention to the educational applications of learning processes based on representational redescription.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1166-1171
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• 2006

Drought is defined by differently for the several scientific and technical fields such as hydrological drought, agricultural drought, meteorological drought, climatological drought, atmospheric drought. A lot of drought indices have been developed to quantify drought severity levels. However these drought indices might be expressed differently as the drought conditions for specific period because the drought severity level is using different types of data on each condition. It is necessary for development of quantative drought representation methods by drought index application. In this research, the reaction to the historical droughts is analyzed after estimation of PDSI, SPI and MSWSI(Modified Surface Water Supply Index) in south korean territory. Lastly the drought representation methods were examiner combining the drought indices by drought indices. The arithmetic mean drought indices that include PDSI, SPI, in yearly basis from 1971 to 2001 and MSWSI in yearly basis from 1974 to 2001 were estimated through the whole nation. The applicability of drought indices are examined based on the observed drought data for national and regional droughts. The result shows that PDSI, SPI(3), SPI(6), and MSWSI have proven to be sensitive enough to the historical drought. The correlation analysis of each drought index was conducted whether they could show the long and short term drought equally. The analysis of how appropriately represent for the historical drought was used for determining for the combined drought index. Consequently, PDSI, SPI(3), SPI(6), and MSWSI have been appeared as suitable indices for the development of quantitative drought representation methods. For the decision of weight on combining PDSI, SPI(3), SPI(6), and MSWSI, drought map was made for eighteen alternative to decide weight. The results showed that PDSI(20%), SPI(3)(60%), SPI(6)(10%), and MSWSI(10%) have been the most well matched weights. Using selected weights of each drought indices and by reconstructing the national mean drought severity on yearly basis, the fact that the year of historical drought is in accordance with the verified one for drought representation. In short, the acquired technique using combined drought index can be used for useful and believable quantitative method of drought analysis.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.470-475
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• 2008

Building Information Modeling(BIM) is rooted in the economic and functional advantages of maturing from paper-based 2D drawings. The paper-based design and construction drawings are typical production from BIM and using the drawing under BIM environment is needed because there is not an alternative media instead of paper-based drawings. However using the 2D drawing process based on 2D CAD for BIM environment directly has difficulties because there are significant differences in data structure between CAD and BIM. CAD is based on traditional drawings as a whole while BIM is focused on individual objects and providing various levels of information associated with the objects. It can be an obstacle to move from 2D CAD to BIM that we don't have a standard or guideline for BIM. Futhermore, the complexity of drawing in representation would be the obstacle too, so the solution is discussed in the research based on the case of Samoo Architects and Engineers.

• Journal of Mechanical Science and Technology
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• v.19 no.2
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• pp.558-566
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• 2005

We propose a feature-based multi-resolution representation of B-rep solid models using history-based Boolean operations based on the merge-and-select algorithm. Because union and subtraction are commutative in the history-based Boolean operations, the integrity of the models at various levels of detail (LOD) is guaranteed for the reordered features regardless of whether the features are subtractive or additive. The multi-resolution solid representation proposed in this paper includes a non-manifold topological merged-set model of all feature primitives as well as a feature-modeling tree reordered consistently with a given LOD criterion. As a result, a B-rep solid model for a given LOD can be provided quickly, because the boundary of the model is evaluated without any geometric calculation and extracted from the merged set by selecting the entities contributing to the LOD model shape.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.1
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• pp.46-54
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• 2002

Plasma Display Panel (PDP) is required to be both the determination of white point of each gray level and the inverse gamma correction since no-balanced RGB cell and linear property of PDP, respectively. However, these two methods cause degradation of grey level representation and undesirable false contour in the dark areas on PDP. In this paper, we implemented real time image processor of the proposed error diffusion algorithm and unsharp masking operation to protect the blurring image caused by the error diffusion. Experimental results showed drastic improvements of gray level representation and reduction of undesirable false contour.

• Speech Sciences
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• v.6
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• pp.119-143
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• 1999

In this paper, the development of English Intonational Phonology is introduced. The existing representation systems of intonation are largely divided into the American structuralist school and the British school, which describe intonation by means of 'levels' and 'configurations' respectively. Both representation systems have some theory-internal problems, however. As for the American school, there is no way to represent pitches much lower than the reference line, while the system of intonation in the British school is limited in that intonation is described in a phonetic impressionistic way rather than from a phonological perspective. Intonational Phonology, a real phonological approach, which has grown out of the basic assumptions of autosegmental-metrical(AM) theory has been suggested by Pierrehumbert(1980). In her approach, an intonational tune is made up of one or more pitch accents, followed by an obligatory phrase accent and an obligatory boundary tone, and interestingly 22 combinations are possible. Intonational Phonology has been revised from Beckman & Pierrehumbert(1986) in developing ToBI(Tones & Break Indices), a proposed standard for labelling prosodic features of digital speech databases in English.