• Proceedings of the KOSOMBE Conference
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• v.1989 no.05
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• pp.39-43
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• 1989

In this paper, hierachical representation method with a 1-to-4 and 1-to-8 data structure is used to reconstruct the three-dimensional scene from two-dimensional cross sections provided by computed tomography with small memory computer system. To reduce the internal memory use, 2-D section is represented by quadtree, and 3-D scene is represented by octree. Octree is constructed by recursively merging consecutive quadtrees. This method uses 7/200 less memory than pointer type structure with all the case, and less memory up to 60.3% than linear octree with experimental data.

• Research in Mathematical Education
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• v.16 no.3
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• pp.177-194
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• 2012

What strategies are used to help students understand quadratic functions in mathematics classroom? In specific, how does Chinese teacher highlight a connection between algebraic representation and graphic representation? From October to November 2009, an experienced teacher classroom was observed. It was found that when students started learning a new type of quadratic function in lessons, the teacher used two different teaching strategies for their learning: (1) Eliciting students to plot the graphs of quadratic functions with pointwise approaches, and then construct the function image in their minds with global approaches; and (2) Presenting a specific mathematical problem, or introducing conception to elicit students to conjecture, and then encouraging them to verify it with appoint approaches.

• Journal of applied mathematics & informatics
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• v.23 no.1_2
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• pp.113-126
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• 2007

Let A and E be $m{\times}n$ matrices and W an $n{\times}m$ matrix, and let $A_{d,w}$ denote the W-weighted Drazin inverse of A. In this paper, a new representation of the W-weighted Drazin inverse of A is given. Some new properties for the W-weighted Drazin inverse $A_{d,w}\;and\;B_{d,w}$ are investigated, where B=A+E. In addition, the Banach-type perturbation theorem for the W-weighted Drazin inverse of A and B are established, and the perturbation bounds for ${\parallel}B_{d,w}{\parallel}\;and\;{\parallel}B_{d,w}-A_{d,w}{\parallel}/{\parallel}A_{d,w}{\parallel}$ are also presented. When A and B are square matrices and W is identity matrix, some known results in the literature related to the Drazin inverse and the group inverse are directly reduced by the results in this paper as special cases.

• Coupled systems mechanics
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• v.10 no.6
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• pp.521-544
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• 2021

In this work, we present the development of a 3D lattice-type model at microscale based upon the Voronoi-cell representation of material microstructure. This model can capture the coupling between mechanic and electric fields with non-linear constitutive behavior for both. More precisely, for electric part we consider the ferroelectric constitutive behavior with the possibility of domain switching polarization, which can be handled in the same fashion as deformation theory of plasticity. For mechanics part, we introduce the constitutive model of plasticity with the Armstrong-Frederick kinematic hardening. This model is used to simulate a complete coupling of the chosen electric and mechanics behavior with a multiscale approach implemented within the same computational architecture.

• Journal of the Korea Society of Computer and Information
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• v.16 no.12
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• pp.157-165
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• 2011

As the contents of information were reinforced the rules of computer science, it was necessary to develop the new teaching and learning plans and various education materials that encourage students and easy to access. So, in this study developed a wide ran of play activities and educational materials without using a computer for the area of information representation and applied to 68 students, second grade of middle school for 4 weeks. After the class, the effect on the learning achievement was verified by the t-test. As a result, it was shown that there was a significant difference between learning with play activities materials and the traditional lecture-type. It means that learning with play activities materials in the information representation influences a positive effect to the learning achievement.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.1062-1073
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• 2007

Acoustic Target Strength (TS) is a major parameter of the active sonar equation, which indicates the ratio of the radiated intensity from the source to the re-radiated intensity by a target. In developing a TS equation, it is assumed that the radiated pressure is known and the re-radiated intensity is unknown. This research provides a TS equation for polygonal plates, which is applicable to near field acoustics. In this research, Helmholtz-Kirchhoff formula is used as the primary equation for solving the re-radiated pressure field; the primary equation contains a surface (double) integral representation. The double integral representation can be reduced to a closed form, which involves only a line (single) integral representation of the boundary of the surface area by applying Stoke's theorem. Use of such line integral representations can reduce the cost of numerical calculation. Also Kirchhoff approximation is used to solve the surface values such as pressure and particle velocity. Finally, a generalized definition of Sonar Cross Section (SCS) that is applicable to near field is suggested. The TS equation for polygonal plates in near field is developed using the three prescribed statements; the redection to line integral representation, Kirchhoff approximation and a generalized definition of SCS. The equation developed in this research is applicable to near field, and therefore, no approximations are allowed except the Kirchhoff approximation. However, examinations with various types of models for reliability show that the equation has good performance in its applications. To analyze a general shape of model, a submarine type model was selected and successfully analyzed.

• The Transactions of the Korea Information Processing Society
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• v.6 no.12
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• pp.3548-3558
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• 1999

There are many kinds of multi-agent frameworks which support the high-level knowledge representation languages for providing intelligence to their agents. But, the agent programming interfaces of the frameworks require to use some general-purpose programming languages as well as tile knowledge representation languages. In general, knowledge representation languages and general-purpose programming languages are different in their levels and data representation models. The differences can make the problems about tile coupling of the elements which are necessary for developing intelligent agents. This paper describes a new type of intelligent agent shell INAS(INtelligent Agent Shell) version 2 which has developed to cope with the problems. Unlike the previous agent frameworks, INAS supports a high-level integrated agent building language for building intelligent agents by itself. Therefore, the development of intelligent agents by using INAS version 2 does not suffer from the problems of the previous agent frameworks. Through the development of several intelligent agents, we experienced that the agent building language of INAS version 2 could reduce the difficulties of developing intelligent agents.

• Journal of Korea Society of Industrial Information Systems
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• v.8 no.3
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• pp.61-68
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• 2003

In this paper, a representation method for structure information retrieval without schema and DTD of XML documents is presented. While existing researches have used DTD or schema to extract structure information, we extract structure information directly from XML documents. Especially the well-formed XML documents are only required to retrieve documents in the proposed method. Thus it can retrieve more general and various documents easily compared to the existing XML retrieval systems requiring DTD or schema. Experimental result indicates that the proposed method retrieves effectively structure information of XML documents independently to DTD information.

• Korean Journal of Childcare and Education
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• v.11 no.1
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• pp.153-171
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• 2015

The purposes of this study were to explore the relations of preschoolers' narrative representation profile types to diurnal cortisol regulation pattern at home. Fourteen story stems from the MacArthur Story Stem Battery (MSSB, Bretherton, et al., 1990) were administered to 40 preschoolers(22 boys, 18 girls, aged 5) recruited from 8 kindergartens in the Seoul and Gyeonggi areas. And also, their saliva cortisol was collected. The children's responses were aggregated into 5 dimensions, based on content themes and performance scores, which included emotions expressed and narrative coherence using the MacArthur Narrative Coding System(Robinson, et al., 2004). Data were analyzed by means of cluster analysis. Five response profiles emerged over the course of this research: Prosocial, Anxiety, Dyregulated aggression, Restricted, and Avoidance profiles. Cortisol at home showed decrease diurnal cortisol regulation patterns, however it showed a difference according to narrative response profiles. Restricted, Prosocial, and Avoidance profiles showed decrease diurnal cortisol regulation patterns. Anxiety profiles showed flat pattern, and Dyregulated aggression profile showed rising diurnal cortisol regulation pattern. These results show the preschoolers' internal representation may affect the diurnal cortisol reaction in daytime.

• Journal of the Korean Mathematical Society
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• v.47 no.3
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• pp.537-546
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• 2010

Multiple discrete Hilbert type inequalities are established in the case of non-homogeneous kernel function by means of Laplace integral representation of associated Dirichlet series. Using newly derived integral expressions for the Mordell-Tornheim Zeta function a set of subsequent special cases, interesting by themselves, are obtained as corollaries of the main inequality.