• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.1
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• pp.5-14
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• 2002

In this paper, we analyze inductive interference in conductive material around 345 kV power transmission line, and evaluate the effects of mitigation wires. Finite element method (FEM) is used to numerically compute induced eddy currents as well as magnetic fields around powder transmission lines. In the analysis model, geometries and electrical properties of various elements such as power transmission line, buried pipe lines, overhead ground wire, and conducting earth are taken into accounts. The calculation shows that mitigation wire reduces fairly good amount of eddy currents in buried pipe line. To find the optimum magnetic field shielding location of mitigation wire, we applied evolution strategy algorithm, a kind of stochastic approach, to the analysis model. Finally, it was shown that we can find more effective shielding effects with optimum location of one mitigation wire than with arbitrary location of multi-mitigation wires around the buried pipe lines.

• Proceedings of the Technology Innovation Conference
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• 1998.06a
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• pp.208-215
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• 1998

Since the advent of conceptual prototype and seminal application, the notion of national systems of innovation(NSI) has drawn an increasing recognition. Although the morphological entanglement is still ubiquitous and the theoretical underpinning is fragile, NSI seems to be the last step toward an increasingly complex and encompassing concept of innovation research. Inevitably, NSI necessitates the comparative analysis in that it normatively attempts to draw best practices. Unfortunately, national profiles are too complex and diverse to derive a unified, concrete representation of the system, posing the problem of defining and modelling NSI for international comparison. This paper aims at providing an inductive taxonomy of NSI based on R&D structure of OECD member economies. Based on the similarity among national profiles, clustering method was applied to identify seven clusters such as (1) enterprise-government funding and enterprise-education performing group, (2) enterprise-government funding and balanced performing group, (3) balanced funding and enterprise-education performing group, (4) balanced funding and performing group, (5) enterprise-dominating group, (6) government-education dominating group and (7) government-education funding and education performing group. This paper by nature is descriptive and exploratory. R&D structure represents a static snapshot of innovative performance since it accounts for only the input side of NSI and thus may not offer convincing explanations of the holistic innovation system. A more detailed and extensive analysis on the economic/technological performance across clusters will shed light on the promising avenue to future research.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.6
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• pp.665-670
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• 2014

A SVM is a kind of binary classifier in order to find optimal hyperplane which separates training data into two groups. Due to its remarkable performance, the SVM is applied in various fields such as inductive inference, binary classification or making predictions. Also it is a representative black box model; there are plenty of actively discussed researches about analyzing trained SVM classifier. This paper conducts a study on a method that is automatically detecting the line-shaped echoes, sun strobe echo and radial interference echo, using the SVM algorithm because the line-shaped echoes appear relatively often and disturb weather forecasting process. Using a spatial clustering method and corrected reflectivity data in the weather radar, the training data is made up with mean reflectivity, size, appearance, centroid altitude and so forth. With actual occurrence cases of the line-shaped echoes, the trained SVM classifier is verified, and analyzed its characteristics using the decision tree method.

• Journal of The Korean Association For Science Education
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• v.28 no.6
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• pp.685-695
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• 2008

An analysis on the Inquiry unit of Science 10 textbooks was conducted in terms of nature of science (NOS). The subject of the analysis was instructional objectives, activities and sentences in the unit of ten Science 10 textbooks. Contents of the instructional objectives could be grouped into nature of science, nature of scientists, scientific methods, and Science-Technology-Society. The concrete nature of scientific knowledge (SK) and constructing scientific theory or model, however, were not found in the objectives. The total number of activities in the Inquiry unit was 38. Seventeen out of them were presented without any supplemental or introductory materials, and 21 activities were provided with information followed by questions, discussions or investigations. For the most activities, any clear statements about NOS elements and desired/informed views of NOS were not made. The sentences of the Inquiry units were mixed up with constructivist and inductive views on NOS. The definition of science tended to be described based on the inductive view. And the generation of SK tended to be described as discovering regularities in natural phenomena rather than constructing theories. For science teachers who want to teach NOS effectively, stating clear learning objectives and elements of NOS and presenting reading materials with relevant views on nature of science were necessary.

• Journal of The Korean Association For Science Education
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• v.27 no.9
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• pp.809-817
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• 2007

The purpose of this research was to investigate the nature of the science views of science teachers and high school students as well as the views expressed in 10th grade science textbooks. The subjects were a high school science teacher, 18 male students and 11 female students in a 10th grade class located in Gyeongbuk Province, Korea. The data were analyzed in terms of three main categories of the nature of the science: the definition of science, the development of science, and the method of science. In the results, it was found that the textbook had an inductivism point of view, and that the teacher had a falsificationism point of view in terms of the definition of science. However, the teacher presented the inductive point of view of the textbook in the class. After the class, the students showed an inductive point of view. In terms of scientific development, the textbook represented a relativism point of view briefly, and the viewpoint of the teacher also expressed relativism. The teacher taught briefly from the relativism point of view, as in the textbook. The viewpoints of the students were inductivism and were not affected by the textbook or the explanations of the teacher. In terms of scientific methods, the viewpoints of the textbook and the teacher were falsificationism, and the teacher represented falsificationism views in her classes. The views of the students also showed falsificationism after their classes. However, before conclusions can be made, it is necessary to find concrete proof of the teaching effect on the viewpoints of the students in continuing research.

• Journal of the Korean earth science society
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• v.26 no.8
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• pp.751-758
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• 2005

The purpose of this study was to develop an inquiry analysis framework based on the features of earth science inquiry methodology and to analyze inquiry activities in the 8th grade 'Earth History and Diastrophism' unit by using this framework. The framework classified earth science methods as logical inference, hermeneutic, and historical methods, each of which was subdivided in consideration of its subordinate methods and characteristics. The analysis revealed that the logical inference method reflected in the unit as the 'abductive method' (70%) was used more frequently than the 'inductive' (23%) and 'deductive' (22%) methods. The hermeneutic method was found in terms of the 'forestructures of understanding' (92%), 'circular reasoning' (9%). and 'historical nature of human understanding' (17%). The historical method also used as the 'constructing proper taxonomy' (53%), 'adhering to the modem principle of uniformitarianism' (47%), and 'relic interpretation' (41%) were identified with ratios more fester than those for the 'place substituting for time in stage theorizing' (3%) and 'evaluating independent lines of inquiry for convergence' (3%).

• Child Health Nursing Research
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• v.11 no.2
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• pp.229-239
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• 2005

Purpose: The objective of this study was to provide an understanding of the difficulties for facing parents of children with terminal cancer. Method: The design of this study was an inductive and descriptive study. Thirty???]one parents of children with terminal cancer participated in???]depth were interviewed s. C in depth and content analysis was used for analyzing the data. Results: The main categories in the findings were 'difficulties in coping', 'physical and psychological suffering of children', 'suffering of family', 'bereavement with children', 'economic problems', 'incurable situation', 'preparation of death', 'social isolation', 'coping after a child dies', 'spiritual problems', receiving active treatment', 'informing children of their condition', 'a sense of meaninglessness', 'emotional iunstability', and 'giving up hope'. Conclusion: The main point identified from this result in this study was that parents who have a child with terminal cancer don't never give up the hope of recovery for their child even when the child is in by the terminal stage of their children, even though and they are unwillingly to prepare for their child's death. This is a unique characteristic in the attitude of the families' attitude in child hospice care and differs from that found in adult hospice care. This result can be used as an important guide for nurses to in assessing the parents' needs in the terminal care setting.

• Journal of The Korean Association For Science Education
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• v.33 no.3
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• pp.639-649
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• 2013

The purpose of this study is to figure out how teachers conduct an experiment in measuring the size of the Earth and how students recognize it. For this study, an in-depth interview was conducted one week after the lesson on the experiment about measuring the size of the Earth. The participants were five secondary school teachers and five secondary school students. The in-depth interview was recorded and transcribed. The result of the interview was drawn through an inductive categorized analysis method. As a conclusion of this study, the teachers taught the students the lesson using alternate angles instead of using the altitude of the Sun. Their lessons were based on Eratosthene's story or some related illustrations suggested in the textbook and not based on an explanation of the principle. Also, students measured the Earth's size only by using alternate angles and didn't understand the meaning of the shadow in the experiment. The results of this study show that teachers need to reconstruct the textbook and understand the accurate experimental principle for the students to have a meaningful experience of the experiment on measuring the size of the Earth.

• Journal of Power Electronics
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• v.15 no.6
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• pp.1654-1663
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• 2015

Compared to LC resonance, LCL resonance has distinct advantages such as a large resonant capability, low voltage and current stresses of the power device, constant voltage or current output characteristics, and fault-tolerance capability. Thus, LCL resonant compensation is employed for a movable Inductive Contactless Power Transfer (ICPT) system with a multi-load in this paper, which achieves constant current output characteristics. Peculiarly, the primary side adopts a much larger compensation inductor than the primary leakage inductor to lower the reactive power, reduce the input current ripple, generate a large current in the primary side, and realize soft-switching. Furthermore, this paper proposes an approximate resonant point for large inductor-ratio LCL resonant compensation through fundamental wave analysis. In addition, the PWM control strategy is used for this system to achieve constant current output characteristics. Finally, an experimental platform is built, whose secondary E-Type coils can ride and move on a primary rail. Simulations and experiments are conducted to verify the effectiveness and accuracy of both the theory and the design method.

• Korean Educational Research Journal
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• v.40 no.1
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• pp.59-79
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• 2019

The purpose of this study is to analyze, through questionnaires and interviews, spacing errors in Chinese students' Korean writing and to propose changes for the teaching methods used for Chinese learners by analyzing the causes of errors. By analyzing the learners' writing samples, a total of 148 space errors were found. The rates of errors (77.6%) that were made by combining separate words is much higher than the errors (22.4%) that were made by placing a space within a compound word. Among the error types, "noun + noun," "observer (type) + dependent noun," and postpositional particle errors occur most frequently. In this paper, we propose the direction of spacing starting from the deductive side and the inductive side for nouns and investigations.