• Communications of Mathematical Education
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• v.36 no.4
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• pp.487-509
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• 2022

The purpose of this study is to analyze classroom discourse in the math classroom of middle school in China, which has a unique math classroom background of entrance examination for high school. To this end, this study analyzed teacher question statistics and episodes by teacher question type as starting speech in mathematics classroom discourse, and five IRF subtypes were especially identified by class discourse structure analysis. The data were analyzed focusing on a total of 15 transcripts of math classes recorded by three math teachers at H School in Guiyang, Guizhou Province, China, and written interviews of teachers. According to the results of this study, an average of 20 teacher questions were observed for each class, and the teacher question type was classified into confirmation question (understanding confirmation question, explanation request question, and double check question) and information question (information presentation question). In addition, according to classroom discourse analysis, the IRF discourse structure was divided into fragmentary evaluation, evaluation+reason, evidence of explanation, evaluation+student response re-statement, guidance on other thoughts or solutions, and student answer correction or teacher opinion presentation.

• School Mathematics
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• v.17 no.2
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• pp.223-239
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• 2015

This study focused on classroom dialogue for communicating spatial information which is supposed to be implemented through learning activities using building-blocks. Even though mathematics textbooks for $2^{nd}$ graders have activities which require abilities of explaining and understanding some spatial information, we know few about how mathematical communication between teacher and students or among students and which strategies are more effective. For this reason, two building-block lessons for $2^{nd}$ graders were observed. The characteristics of teachers' instruction and students' explanation were identified and the mathematical communication between teachers and students or among students was analyzed. As a result, mains factors of impeding students' explanation and understanding were induced and the types of their communication were classified. Based on these results, several teaching strategies for effective communication in buildingblock lessons were suggested.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.627-630
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• 2002

In the present study a mesh generation program is developed for the flow analysis of industrial mixers. With this program one can select various design parameters such as impeller types, vessel type, number of baffles, number of blades, blade pitched angle, stages of impeller, rotational speed etc. Post processing capabilities are also imbedded in the program. Along with brief explanation of the program, examples of flow simulation for various type of mixers by using the program are also presented to show effectiveness of the program. It is expected that this program can be used to understand the effect of design parameters on the performance of particular type of the mixer, and hence to achieve the optimal design.

• Journal of Educational Research in Mathematics
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• v.11 no.2
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• pp.385-402
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• 2001

The purpose of this study is to conceptualize 'proof' school mathematics. We based on the assumption the following. (a) There are several different roles of 'proof' : verification, explanation, systematization, discovery, communication (b) Accepted criteria for the validity and rigor of a mathematical 'proof' is decided by negotiation of school mathematics community. (c) There are dynamic relations between mathematical proof and empirical theory. We need to rethink the nature of mathematical proof and give appropriate consideration to the different types of proof related to the cognitive development of the notion of proof. 'proof' in school mathematics should be conceptualized in the broader, psychological sense of justification rather than in the narrow sense of deductive, formal proof 'proof' has not been taught in elementary mathematics, traditionally, Most students have had little exposure to the ideas of proof before the geometry. However, 'proof' cannot simply be taught in a single unit. Rather, proof must be a consistent part of students' mathematical experience in all grades, in all mathematics.

• Journal of Photoscience
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• v.8 no.1
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• pp.33-37
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• 2001

Picosecond absorption spectroscopy has been employed in the study of the solvent dynamics of 1, 2, 4, 5-tetracyanobenzene/biphenyl derivative radical ion pairs, and the resulting rates of radical ion pair separation are faster in acetonitrile than in dichloromethane. In an effort to account quantitatively for such solvent effect on the rate of radical ion pair separation, an equation for the rate of radical ion pair separation is introduced, in which the rate depends exponentially on the electrostatic interaction energy in the radical ion pair. In our analysis of the types of electrostatic interaction energy based on the conducting spheres in dielectric continuum was chosen, and the rate equation employing this electrostatic energy provided information on the distance on the distance of radical ion pair separation and solvation energy of the radical ion pair, thereby providing quantitative explanation for the observed solvent effect on the rate of radical ion pair sepaaration.

• Journal of the Korean Home Economics Association
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• v.42 no.12 s.202
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• pp.123-140
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• 2004

The purpose of this study was to explore the unfairness of adhesion contracts for internet contents service. The internet contents were classified into six types of avatar, learning, download, e-book and movie internet sites. The adhesion contracts of internet contents service were collected in 60 internet sites. The unfairness of the adhesion contract was reviewed under the adhesion contract regulation act. The major results were as follows. First, the obligation of clear statement, explanation, and delivery was not observed completely. Second, many articles of adhesion contract were unfair and they especially violated articles 7 and 9. Therefore, the standard adhesion contract system for internet content service should be enforced and self-regulation of information service providers is needed.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1893-1896
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• 2002

Remediation Selection Expert System (RSES) is a rule-based expert system which is used far the selection of remediation techniques fur petroleum contaminated sites. In this paper, we describe a fuzzy logic-based sub-system: Site Characterization Sub-System (SCSS). It is an enhancement of the RSES, which is used to analyze the hydraulic properties of contaminated sites. This paper focuses on an explanation on how to apply fuzzy set theory for identification of soil types and hydraulic properties of a contaminated site. To illustrate application of fuzzy set theory to the problem, two sample cases are presented in detail.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.8 no.12
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• pp.49-63
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• 1985

This paper is focused on the introduction of the types of models and explanation of the fundamental concepts and theory for development and use of the corporate planning and modeling system. Nowadays, a great deal of companies have been or experimenting with some form of a corporate planning and modeling system to support managerial and strategic decision making. From previous studies it was noted that most applications have tended to be financially based. This trend will probably continue. However, with the software and hardware currently available it is likely that companies will move more toward integrated models that link marketing, production, as will as financial areas. More emphasis will undoubtedly be placed on the use of econometric modeling, since this subelement of the overall planning and modeling process is closely tied to the market place and the economy. At any rate, wherever the development of corporate planning and modeling system is directed, clear understanding for the fundamental concepts and elements of the system is settled in advance in order to develope and use it.

• Journal of Korean Neurosurgical Society
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• v.30 no.11
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• pp.1328-1331
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• 2001

Multiple primary brain tumors of different cell types are rare, accounting for 0.4% of all the primary brain tumors. Phakomatosis, irradiation, trauma and other factors have been associated with multiplicity of brain tumors. When these tumors are close or intermixed, the term "collision" has been used, and in these cases an explanation might be that one tumor stimulating the other. We report a patient with collision tumor of meningioma and anaplastic astrocytoma, who did not have a history of trauma, irradiation, or phakomatosis.

• Journal of Communications and Networks
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• v.10 no.1
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• pp.89-97
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• 2008

Anomaly detection systems playa significant role in protection mechanism against attacks launched on a network. The greatest challenge in designing systems detecting anomalous exploits is defining what to measure. Effective yet simple, Shannon entropy metrics have been successfully used to detect specific types of malicious traffic in a number of commercially available IDS's. We believe that Renyi entropy measures can also adequately describe the characteristics of a network as a whole as well as detect abnormal traces in the observed traffic. In addition, Renyi entropy metrics might boost sensitivity of the methods when disambiguating certain anomalous patterns. In this paper we describe our efforts to understand how Renyi mutual information can be applied to anomaly detection as an offline computation. An initial analysis has been performed to determine how well fast spreading worms (Slammer, Code Red, and Welchia) can be detected using our technique. We use both synthetic and real data audits to illustrate the potentials of our method and provide a tentative explanation of the results.