• Journal of Power Electronics
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• v.17 no.3
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• pp.725-732
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• 2017

This paper proposed a real-time, low-cost, fast transistor open-circuit fault diagnosis method for voltage-source inverter fed induction motors. A transistor open-circuit changes the symmetry of the inverter topology, leading to different similarities among three phase load currents. In this paper, dynamic time warping is proposed to describe the similarities among load currents. The proposed diagnosis is independent of the system model and needs no extra sensors or electrical circuits. Both simulation and experimental results show the high efficiency of the proposed fault diagnosis method.

• Educational Technology International
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• v.12 no.1
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• pp.47-66
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• 2011

This study examines strategies and obstacles encountered in infusing digital resources in the middle school mathematics and science classroom. It draws on data from principals, technology coordinators and math and science teachers in three urban middle schools in United States. All three of these schools have recently invested heavily in technology hardware and high speed Internet connectivity and as such they provide an opportunity to look beyond well documented obstacles such as outdated computers and poor Internet access. The logistical, preparatory, pedagogical and curricular challenges encountered by teachers within the study have important implications for professional development efforts aimed at improving science education through the integration of Web-based resources.

• 대한공업교육학회지
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• v.31 no.2
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• pp.155-176
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• 2006

The purpose of this study was to explore the strategies for applying TRIZ to technology education. This study was carried out through literature review on contradiction, 40 principles, 76 standard solutions, multi screen method, effects, the law of technology evolution, and ARIZ, and questionnaire survey to investigate the validity. Through this study the strategies for applying TRIZ to technology education were proposed and the validity was identified. Only the '40 Principles' was appropriate to technology education of elementary and middle school. The results of this study were as follows; In elementary school technology education, segmentation, extraction, local quality, asymmetry, consolidation, universality, counterweight, do it in reverse, mediator, self service, dispose, flexible membranes or thin films, changing the color, homogeneity, rejecting and regenerating parts, and composite materials were suitable. And in middle school technology education, segmentation, extraction, local quality, asymmetry, consolidation, universality, counterweight, prior counteraction, prior action, cushion in advance, do it in reverse, dynamicity, partial or excessive action, continuity of useful action, convert harm into benefit, mediator, self service, dispose, flexible membranes or thin films, changing the color, homogeneity, rejecting and regenerating parts, transformation of properties, phase transition, thermal expansion, and composite materials were suitable.

• Educational Technology International
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• v.13 no.1
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• pp.27-48
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• 2012

In this paper we are comparing how the OER (open educational resources) are developed in Higher Education in Finland and South Korea. We also present a comparison model for further studies. Essential findings based on our comparison are that in both countries there are many best practices of use of the OER and open learning. Open educational resources have great potential and their use can ensure quality teaching and learning. The activity has not inspired the great mass of higher education teachers in Finland and Korea. Traditionally, a teacher's job is working alone, and so a new operational culture is required. Our comparison indicates that numerous questions, fears and problems and cultural differences are also related to the thematic. There is an evident need for a new kind of strategic leadership, a new kind of teaching and learning culture and a doing together and production ideology for the method to spread. Based on our study the following interlinked elements of OER seem to be pivotal: changes to pedagogies, technology and operational culture; educational policy intention; and attitude to culture. Lastly, comparison frame by OER practice model is developed.

• 대한공업교육학회지
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• v.34 no.1
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• pp.252-273
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• 2009

Due to the importance of biotechnological literacy, the educational community in fields such as technology education, science education, and agricultural education has acknowledged the importance of biotechnology instruction for secondary school. Although recognized as a content organizer in the field of technology education, the actual teaching of biotechnology has not been broadly implemented in technology education classes. In the perspective of expectancy-value theory, technology teachers' motivation is the key factor for affecting the biotechnology instruction. This study investigates Korean technology teachers' motivational beliefs toward biotechnology and its instruction and their perceived ability and value toward biotechnology learning contents. To measure their motivational beliefs and attitudes, a composite on-line survey (fifteen motivational beliefs items, eight biotechnology content items, and related demographic items) was developed. Based on 114 Korean technology teachers' responses the researcher performed a descriptive analysis, independent t-test, and factor analyses (exploratory and confirmatory factor analysis using M-plus 5.0 and SPSS 16.0). Korean technology teachers' abilities toward eight biotechnology contents indicated lowscores while their values were relatively high. Through the independent sample t-test by two demographic variables (gender and professional development), this study found several significant differences in the perceived value. As a preliminary finding of exploratory factor analysis, fifteen items was separated into two motivational constructs of expectancy (6 items) and value (8 items). One item (item #6) was eliminated due to the cross loading. The final findings of this study may have significant implications for professional development regarding biotechnology and its instruction (both in-service and pre-service training) of technology teachers. Also, the confirmatory facctor analysis supported the preliminary finding. Finally, this study recommends that a validity test for other population, investigation for motivational sub-constructs, and in-depth investigation toward biotechnology instruction.

• International Journal of Advanced Culture Technology
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• v.12 no.1
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• pp.11-15
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• 2024

Video is already playing an educational role. Now, it is necessary to discuss the issue of the effectiveness of video education in schools. Facilitation is a great means of maximizing learning effects beyond the creativity and autonomy of video production. To prove this, a research study was conducted, and the results showed that facilitation had a significant effect on the learning effect. Based on this result, various policy suggestions such as the introduction of facilitation in the educational field are made.

• Journal of The Korean Association For Science Education
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• v.12 no.3
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• pp.119-128
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• 1992

The contents of two elementary science textbooks are analyzed; they are HBJ Science and Holt Science. A) The ratio of the contents is as follows physics area, 21-27% ; chemistry area, 6-7% ; biology area, 32-41% ; earth science area, '27-31 %. B) The jobs related in science and technology are introudced in both textbooks. The kinds of jobs found in Holt Science and HBJ Science are 94 and 55, respectively. C) There cent developments in science and technology are introduced in Holt Science and HBJ Science are 57 and 46 times respectively. The introductoin of the recent development of science & technology and the jobs relcated in science & technology may interest children in science.

• Journal of the Korean Ceramic Society
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• v.48 no.2
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• pp.195-199
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• 2011

The effect of copper oxide on migration and interaction of protons in barium zirconate was investigated using density functional theory. One copper atom was substituted for a zirconium atom site, and a proton was added to a $3{\times}3{\times}3$ barium zirconate superstructure. An energy barrier of 0.89 eV for proton migration was the highest among several energy barriers. To investigate the interaction between multiple protons and a copper atom, two protons were added to the superstructure. Various proton positions were determined by the interaction between the two protons and the copper atom.

• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2069-2087
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• 2023

In nuclear power plant (NPP) accidents, the containment is subject to high temperatures and high internal pressures, which may further trigger serious chain accidents such as core meltdown and hydrogen explosion, resulting in a significantly higher accident level. Therefore, studying the mechanical performance of a containment under high temperature and high internal pressure is relevant to the safety of NPPs. Based on similarity principles, the 1:3.2 scale model of a prestressed concrete containment vessel (PCCV) of a NPP was designed. The loading method, which considers the thermal-pressure coupling conditions, was used. The mechanical response of the PCCV was investigated with a simultaneous increase in internal pressure and temperature, and the failure mechanism of the PCCV under thermal-pressure coupling conditions was revealed.

• Journal of Practical Engineering Education
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• v.16 no.3_spc
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• pp.297-308
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• 2024

This study explored the application of the NFT-based Learn-and-Earn model in metaverse vocational education and training. Through expert interviews, Delphi analysis, and AHP analysis, the study evaluated considerations and importance of L&E model operation, NFT technology application, course history and certification management, teaching media copyright management, and platform-related issues. Based on the results, the study suggested the need for performance measurement, infrastructure establishment, institutional arrangement, and ethical issue response when utilizing the L&E model.