• Journal of the Korean Society for Nondestructive Testing
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• v.24 no.1
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• pp.8-14
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• 2004

Model-based inversion tools for eddy current signals have been developed by combining neural networks and finite element modeling, for quantitative flaw characterization in steam generator tubes. In the present work, interpretation of experimental eddy current signals was carried out in order to validate the developed inversion tools. A database was constructed using the synthetic flaw signals generated by the finite element model. The hybrid neural networks composed of a PNN classifier and BPNN size estimators were trained using the synthetic signals. Experimental eddy current signals were obtained from axisymmetric artificial flaws. Interpretation of flaw signals was conducted by feeding the experimental signals into the neural networks. The interpretation was excellent, which shows that the developed inversion tools would be applicable to the Interpretation of real eddy current signals.

• School Mathematics
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• v.4 no.2
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• pp.161-192
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• 2002

This paper investigated the teaching and teaming of contents-related graphing in Korean secondary textbooks and suggested the improved methods of graph instruction through this analysis. reification-the case of function, In Harel, G., Dubinsky(Eds.), The Concept of Function : Aspects of Epistemology and Pedagogy Textbooks are analyzed from the viewpoint of the proportion of graphing contents, their sequencing, the proportion of each domain in graphing activities (interpretation vs. construction, quantitative vs. qualitative aspect, local vs. global aspect) and tasks (prediction, translation, scaling), and the difference in the graphing contents between the sixth and the seventh curriculum. This analysis demonstrates that graphing contents are increasing in textbooks, therefore the high school textbooks appear in almost every content area. The graphing activities concentrate on the construction, the quantitative aspects, and the local aspects, and are gradually focusing on the interpretation and global aspects of high school textbooks. Furthermore, most of graphing tasks favor translation. In contrast, the current seventh curriculum includes a balance of interpretation and construction activities and has more global aspects than the sixth curriculum based textbooks; however, the qualitative approach still rarely appears. For the graphing tasks, translation is still prevalent, but the importances of prediction tasks based on graph have increased in comparison with the sixth curriculum textbooks. Further, the seventh curriculum based textbooks are designed to stimulate more dynamic graphing instruction by introducing new tools such as graphing calculators and computer software. We suggest that the qualitative and global aspects should be emphasized in early graph instruction, a variety of graph activities in realistic contexts should be performed, and educational technology such as graphing calculator and computer can be efficient to implement these ideas.

• Journal of Soil and Groundwater Environment
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• v.26 no.6
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• pp.1-17
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• 2021

Self-potential (SP) surveys measure naturally occurring differences in electrical potential in the absence of artificial sources and have been applied to various fields since the first application in mineral explorations. Among various causes of SP occurrences, streaming potential is generated by the flow of groundwater, and makes SP surveys suitable for the exploration of groundwater table fluctuation, fractures, sinkholes and landslide occurrences. Recently, there has been many studies that applied SP surveys to monitor water leakage through dikes and embankments. In this review paper, we first review the characteristics and theoretical backgrounds of streaming potential in saturated or unsaturated porous media to introduce it in the embankment among various application field. After the review of the background theory, we review the past cases of field SP surveys on dikes and embankments and also the characteristics of field streaming potential data in the surveys. Further, by analyzing past studies of qualitative as well as quantitative interpretation of SP survey data, we show the possibility of quantitative interpretation of streaming potential data obtained on dikes and embankments. Consequently, it is hope that this review paper helps researches on SP surveys on dikes and embankments, and provides basis for interpretation methods of the SP data to identify leaked area and further leakage rate (or permeability).

• Economic and Environmental Geology
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• v.21 no.1
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• pp.85-96
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• 1988

Geophysical well logging at various coal fields were carried out to study the characteristic response of domestic coal seams. Also a computer program is developed for quantitative analysis of coal logging data. Most coal seams penetrated by the drill holes, where the well logging were carried out, showed poor thickness and quality, and were severely altered. Therefore, majority of log data are inadequate for detailed quantitative analysis. The logs show, however, typical characteristics with related to coal seams, but interpretation should be made with caution because certain log response of demestic coals, mostly anthracite, are quite different to those of foreign coals, mostly bituminous. The developed comuter program has been proved as an effective one for identification of coal seams and lithology anslysis, and is expected to be succesfully used for coal quality analysis in cases of more diversified log data of good quality being obtained.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.6
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• pp.546-552
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• 2016

We present a quantitative evaluation of an algorithm for model-based face recognition. The algorithm actively learns how individual faces vary through video sequences, providing on-line suppression of confounding factors such as expression, lighting and pose. By actively decoupling sources of image variation, the algorithm provides a framework in which identity evidence can be integrated over a sequence. We demonstrate that face recognition can be considerably improved by the analysis of video sequences. The method presented is widely applicable in many multi-class interpretation problems.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.123-126
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• 1998

We have conducted surface electrical resistivity surveys along with the electrical logging at Bookil-Myun, Chungwon-Goon, Choongchungbuk-Do to determine the depths of basement and water table, and for the purpose of preparing the basic input data for hydrogeologic model combined with GIS. A twenty lines of dipole-dipole array survey and a twenty-five stations of resistivity sounding were performed and ten holes were employed for electrical logging to cross check the surface data. A combined interpretation gave the quantitative information of the shallow geologic structure over the area and we constructed layers using the grid analysis of Arc/info. The constructed layers were turned out to be similar to the geologic structure confirmed from the drilling data and we concluded that the methodology adopted in this study would be applicable to hydrogeologic model setup as a tool of providing the basic input data.

• Journal of the Korean earth science society
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• v.25 no.3
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• pp.152-159
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• 2004

The purpose of this study was to explore characteristics of natural history museum exhibits from the viewpoint of science education. A total of ninety exhibits for this study were examined in national science museums of Korea and Japan. Exhibits of Tokyo national science museum were again divided into two groups: the old and traditional types, and the new and renovated ones. Even though analyzing data was not undertaken through quantitative statistical process, the interpretation of the data was valid enough to fulfill the purpose of the research. While there were clear changes and differences between the old and the new types of exhibits in Tokyo national science museum, the old part of Tokyo museum was similar to one in Korea. Based on analyzing the new types of Tokyo museum, the current movement in the field of natural history museums of Korea explicitly has toward utilizing more science education concepts and ideas.

• Journal of The Korean Association For Science Education
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• v.21 no.2
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• pp.255-263
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• 2001

The purpose of this study is to analyse the eighth grade students' performance of open investigations for two kinds of tasks: the qualitative one which involves the descriptive approach through observation, and the quantitative one which involves the quantitative data processing through control of variables. Researcher's observation, interview data as well as students' investigation reports, self-evaluations were analysed. The difficulties of qualitative open investigation lie in detecting and dealing with unexpected observations, of which the acceptance and interpretation were influenced by preconceptions. On the other hand, managing several variables, making reliable and valid measures, and quantitative data processing constituted main difficulties of quantitative open investigation. Some students could recognize the deficiencies of their methods and findings in qualitative one, but few in quantitative one. These results suggest the teaching point for each task of open investigations.

• Investigative Magnetic Resonance Imaging
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• v.24 no.1
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• pp.1-20
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• 2020

This document is the third part of the guidelines for the interpretation and post-processing of cardiac magnetic resonance (CMR) studies. These consensus recommendations have been developed by a Consensus Committee of the Korean Society of Cardiovascular Imaging (KOSCI) to standardize the requirements for image interpretation and post-processing of CMR. This third part of the recommendations describes tissue characterization modules, including perfusion, late gadolinium enhancement, and T1- and T2 mapping. Additionally, this document provides guidance for visual and quantitative assessment, consisting of "What-to-See," "How-To," and common pitfalls for the analysis of each module. The Consensus Committee hopes that this document will contribute to the standardization of image interpretation and post-processing of CMR studies.

• Journal of the Korean earth science society
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• v.40 no.6
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• pp.639-653
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• 2019

The purpose of this study is to investigate the science gifted students' level of interpreting the oceanic graph and of understanding the oceanic physical concept through analyzing the Temperature-Salinity (T-S) diagram and inferring the SOFAR (SOund Fixing And Ranging) channel. A total of 106 gifted students in the 3rd year of a science gifted high school, using T-S diagrams published in one of the journals of Oceanology, developed descriptive questions asking the depth of the SOFAR channel to conduct the quantitative and qualitative analysis of graph interpretation ability. As a result, there was a big difference in the level of graphs interpretation and concepts understanding for each science gifted students such as interpreting, modeling, and converting, and exposed their alternative concepts about water temperature, salinity, and density. The results of this study will be used to understand the levels of science gifted students' graph interpretation in oceanology, and to provide the basic data for improving the teaching and learning methods of oceanology and also provide basic data for teaching material development related to graph analysis.