• The Korean Journal of Applied Statistics
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• v.26 no.2
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• pp.335-347
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• 2013

There are various types of real world signals. For example, an electrocardiogram(ECG) represents myocardium activities (contraction and relaxation) according to the beating of the heart. ECG can be expressed as the fluctuation of ampere ratings over time. A signal is a composite of various types of signals. An orchestra (which boasts a beautiful melody) consists of a variety of instruments with a unique frequency; subsequently, each sound is combined to form a perfect harmony. Various research on how to to decompose mixed stationary signals have been conducted. In the case of non-stationary signals, there is a limitation to use methodologies for stationary signals. Huang et al. (1998) proposed empirical mode decomposition(EMD) to deal with non-stationarity. EMD provides a data-driven approach to decompose a signal into intrinsic mode functions according to local oscillation through the identification of local extrema. However, due to the repeating process in the construction of envelopes, EMD algorithm is not efficient and not robust to a noise, and its computational complexity tends to increase as the size of a signal grows. In this research, we propose a new method to extract a local oscillation embedded in a signal by utilizing the second derivative.

• Education of Primary School Mathematics
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• v.16 no.1
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• pp.35-55
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• 2013

The purposes of this study were to development and verify the effect of educational program apply on STEAM for the mathematical prodigy. To accomplish these purposes literature review on development of the program and qualitative study were conducted. The mixed-model design was applied for this qualitative experimental study. The conclusions of this study were as follows. First, the program for mathematical prodigy education applied on the conceptual model of STEAM integration approach was developed. Second, a learning satisfaction about constitution of the workbook was lowly. Third, principal of STEAM was the best interest and difficult of the program applied on STEAM. Fourth, the creativity and problem solving ability was founded about angle and velocity of mathematical domain and making the Angrybirds Game on GeoGebra environment. In spite of difficulty about principal of the Angrybirds Game, confidence and satisfaction were founded about a result product.

• Education of Primary School Mathematics
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• v.23 no.2
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• pp.73-85
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• 2020

The purpose of this study was to examine the influence of the auxiliary questions of word problems presented to students on their problem solving-strategies and mathematical thinking and to discuss the educational implications of the results. As a result of making an analysis, problems that included auxiliary questions to give information on workable problem-solving strategies made it more possible for students of different levels to do relatively equal mathematical thinking than problems that didn't by inducing them to adopt efficient problem-solving strategies. And they were helpful for the students in the middle and lower tiers to find a clue for problem solving without giving up. But it's unclear whether the problems that provided possible strategies through the auxiliary questions stirred up the analogical thinking of the students. In addition, due to the impact of the problems provided, some students failed to adopt a strategy that they could have come up with on their own. On the contrary, when the students solved word problems that just offered basic recommendation by minimizing auxiliary questions, the upper-tiered students could devise various strategies, but in the case of the students in the middle and lower tiers, those who gave up easily or who couldn't find an answer were relatively larger in number.

• Journal of Gifted/Talented Education
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• v.20 no.3
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• pp.743-765
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• 2010

The purpose of this study was to provide and analyze the fundamental data on leadership skills and to analyze leadership skills among giftd elementary students according to grade, subject and gender. The main research questions in order to achieve the purpose of research are as follow. First, are there any differences of gifted elementary students' leadership skills in gifted groups? Second, do leadership program have an effect on improvement of gifted elementary students' leadership skills? The subjects for this study were 488 gifted elementary in 4th-6th grade in Busan. The students in the experiential group went thought 16 session do leadership program. After that, they had pre-tests and post-tests. the devices used to verify the effectiveness of the program were leadership skill scales. For this research analysis, MANOVA was used to investigate the first research questions and MANCOVA was used to investigate the second research question. Results from this study are as follows. Firstly, students in higher grades received fewer leadership skills points. This fact suggests that the leadership programs from the fourth grade should be implemented in 5th and 6th grade gifted education as well. Secondly, in the analysis of the results from gifted mathematics and gifted science, little significant statistical difference was shown. Thirdly, the analysis of leadership skills according to gender showed statistical significance. Finally, the study showed that the leadership education program had a positive effect. So the gifted 4th, 5th, and 6th grade students improve their leadership skills points by the end of the 16 week programs. Consequently, it is suggested that leadership education program on gifted elementary education was significant to improvement of leadership skills.

• Journal of Gifted/Talented Education
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• v.23 no.3
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• pp.355-371
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• 2013

While many research focused learners as those who excel in mathematics or science, the identification of learners with potential or demonstrated talent in visual art has also been the meaningful research topic. Since these learners exhibit high performance capability in intellectual, creative and artistic areas, they require services or programs not ordinarily provided by the schools. This research tried to clarify what high performance means when speaking of learners with outstanding talent in the visual arts based on the relevant literature. Also, this research introduced the recent trends in the field of art gifted and talented education. In order to demonstrate critical issues and find new directions in art education for gifted learners, this research conducted the survey, and this survey target group was arts high school students. Based on the survey analysis, this research conducted the semi-structured interviews with focal participants including the teachers and an artist. Interviewees generated many meaningful issues, and interview analysis reconceptualized art education for gifted learners as following. 1) Gifted education should consider learners' excellence, equity, troubles, and struggles that often go unnoticed. 2) We should reform the criteria, standards, and strategies in finding art gifted learners. 3) In order to facilitate meaningful and creative art education, higher education institutions need to change the current college entrance exam. 4) The goal of gifted art education is not only raising the world-class artists. 5) Meaningful art education for gifted learners is in interaction with the environment including group dynamics, parents influence, and teachers.

• Anatomy & Biological Anthropology
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• v.29 no.2
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• pp.35-46
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• 2016

Leonardo da Vinci is remembered as the greatest genius of the Renaissance. He left outstanding achievements as an artist, scientist and inventor, and contributes up to today's science. He ranks the best in a variety of fields, such as botany, mathematics, geology, astronomy, geometry and optics. It has well known that Leonardo is an artist, scientist, inventor and philosopher. And he was a great anatomist that dissected dead bodies and animals directly and left many anatomical drawings. He took an interest in anatomy from the point of view of the artist, which is why the human body structure and function to know the sakes were "ignorant of the anatomy should not be upset." Over time, he became interested in the structure and function of the body, even get the human body in a difficult environment; he dissected many the human bodies directly. His scientific inquiry and infatuation made him as an advanced pioneer for more than 100 years, and got enough level to surpass the artistry. Leonardo left about 1,800 anatomical figures of the muscular, skeletal, vascular, nervous and urogenital system, and they are also very scientific and high artistic achievements. The aim of this article is to take a look at Leonardo da Vinci's anatomical achievements and thoughts. In addition, the goal is to knowledge today's anatomists about Leonardo da Vinci's astonishing achievements as a great pioneer in anatomy.

• Journal of health informatics and statistics
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• v.42 no.4
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• pp.309-316
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• 2017

Objectives: Radon and its progeny pose environmental risks as a carcinogen, especially to the lungs. Investigating factors affecting indoor radon concentrations and models thereof are needed to prevent exposure to radon and to reduce indoor radon concentrations. The purpose of this study was to identify factors affecting indoor radon concentration and to construct a comprehensive model thereof. Methods: Questionnaires were administered to obtain data on residential environments, including building materials and life style. Decision tree and structural equation modeling were applied to predict residences at risk for higher radon concentrations and to develop the comprehensive model. Results: Greenery ratio, impermeable layer ratio, residence at ground level, daily ventilation, long-term heating, crack around the measuring device, and bedroom were significantly shown to be predictive factors of higher indoor radon concentrations. Daily ventilation reduced the probability of homes having indoor radon concentrations ${\geq}200Bq/m^3$ by 11.6%. Meanwhile, a greenery ratio ${\geq}65%$ without daily ventilation increased this probability by 15.3% compared to daily ventilation. The constructed model indicated greenery ratio and ventilation rate directly affecting indoor radon concentrations. Conclusions: Our model highlights the combined influences of geographical properties, groundwater, and lifestyle factors of an individual resident on indoor radon concentrations in Korea.

• Cross-Cultural Studies
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• v.33
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• pp.143-169
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• 2013

Recently, because of the danger and damages that following the steady development of scientific technologies, natural science is faced with many humane and ethical problems. So it is asserted the interdisciplinary with social and human science. However, it comes commonly that the ethical issues such as world view and one's view of life caused the development of sociology, especially development of the market economy. But in many cases, the interdisciplinary can be useful for widen the view of scholars. The interdisciplinary is actually connected with the problems of philosophy, and located in that domain. In this case, this is noticed as a model to the philosophers in 18th century, especially Denis Diderot. Diderot published De $l^{\prime}interpr{\acute{e}}tation$ de la nature during editing the Encyclopedia, from there he picked out the contents from piles of documents of Encyclopedia. Even though the contents or opinions of De $l^{\prime}interpr{\acute{e}}tation$ de la nature are inaccuracy or erroneous, it shows that how human-social science and natural science encountered. Diderot studied mathematics and then Diderot accepted to the natural science proposal, he approaches philosophy with translate English books to the French. Next he understood natural science by reading Buffon and Maupertuis, and during working for Encyclopedia, he possessed his knowledge that he can claim his opinion to other scholars. However in this De $l^{\prime}interpr{\acute{e}}tation$ de la nature, Diderot who sometimes rebutted other scholars' theory and demonstration, tried to build a philosophy on metaphysics in order to it was important for himself that he imposed the methods of science and importance of experience. Anyhow, this De $l^{\prime}interpr{\acute{e}}tation$ de la nature cause consider the recognition of Diderot in the field of natural science, and is suggested as a model about his Nature. This mean that it is an expression of his philosophy, and the content is found from natural philosophy and empirical philosophy. Like giving these attache the importance of method study for science and technique, these are targeted the promotion of popularization of natural-science and scientific-technology. Also it advocates fulfilling from reasonable philosophy to empirical philosophy. Therefore, the philosophy which was speculative and abstracted became his philosophy which was writing the meaning, as waiting the discovery of science. And at that time, the humanities made interdisciplinary with natural science.

• Korean Journal of Remote Sensing
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• v.15 no.2
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• pp.91-105
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• 1999

Spatial data integration using multiple geo-based data sets has been regarded as one of the primary GIS application issues. As for this issue, several integration schemes have been developed as the perspectives of mathematical geology or geo-mathematics. However, research-based approaches for statistical/quantitative assessments between integrated layer and input layers are not fully considered yet. Related to this niche point, in this study, spatial data integration using multiple geoscientific data sets by known integration algorithms was primarily performed. For spatial integration by using raster-based GIS functionality, geological, geochemical, geophysical data sets, DEM-driven data sets and remotely sensed imagery data sets from the Ogdong area were utilized for geological thematic mapping related by mineral potential mapping. In addition, statistical/quantitative information extraction with respective to relationships among used data sets and/or between each data set and integrated layer was carried out, with the scope of multiple data fusion and schematic statistical assessment methodology. As for the spatial integration scheme, certainty factor (CF) estimation and principal component analysis (PCA) were applied. However, this study was not aimed at direct comparison of both methodologies; whereas, for the statistical/quantitative assessment between integrated layer and input layers, some statistical methodologies based on contingency table were focused. Especially, for the bias reduction, jackknife technique was also applied in PCA-based spatial integration. Through the statistic analyses with respect to the integration information in this case study, new information for relationships of integrated layer and input layers was extracted. In addition, influence effects of input data sets with respect to integrated layer were assessed. This kind of approach provides a decision-making information in the viewpoint of GIS and is also exploratory data analysis in conjunction with GIS and geoscientific application, especially handing spatial integration or data fusion with complex variable data sets.

• Education of Primary School Mathematics
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• v.22 no.4
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• pp.205-221
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• 2019

The study aimed at investigating preservice elementary school teachers' statistical reasoning when they posed survey questions as they engaged in statistical problem solving, and analyzing how their statistical reasoning affect the subsequent stages. 24 groups of sophomore students(80 students) from two education universities conducted statistical problem solving and completed statistical report, and 22 of them were analyzed. As a result, 9 statistical reasoning were shown when preservice teachers posed survey questions. Among them, question clarification oriented reasoning and variability based reasoning were not exclusively focused upon in the previous research. In order to investigate how statistical reasoning in posing survey questions affected subsequent stages, we examined difficulties and issues that preservice teachers had when they engaged in analyses and conclusion stage described in their report. Consequently, preservice teachers' difficulties were related to population relevant reasoning, category level reasoning, standardization reasoning, alignment to question reasoning, and question clarification oriented reasoning. While previous studies did not focus on question posing stage, this study claimed the necessity of emphasizing various statistical reasoning in question posing and importance of teaching and learning method of appropriate statistical reasoning in question posing.