• Nuclear Engineering and Technology
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• v.56 no.4
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• pp.1501-1512
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• 2024

Plasma disruption in tokamak experiments is a challenging issue that causes damage to the device. Reliable prediction methods are needed, but the lack of full understanding of plasma disruption limits the effectiveness of physics-driven methods. Data-driven methods based on supervised learning are commonly used, and they rely on labelled training data. However, manual labelling of disruption precursors is a time-consuming and challenging task, as some precursors are difficult to accurately identify. The mainstream labelling methods assume that the precursor onset occurs at a fixed time before disruption, which leads to mislabeled samples and suboptimal prediction performance. In this paper, we present disruption prediction methods based on anomaly detection to address these issues, demonstrating good prediction performance on J-TEXT and EAST. By evaluating precursor onset times using different anomaly detection algorithms, it is found that labelling methods can be improved since the onset times of different shots are not necessarily the same. The study optimizes precursor labelling using the onset times inferred by the anomaly detection predictor and test the optimized labels on supervised learning disruption predictors. The results on J-TEXT and EAST show that the models trained on the optimized labels outperform those trained on fixed onset time labels.

• Journal of Engineering Education Research
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• v.20 no.3
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• pp.50-57
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• 2017

The purpose of this study was verify the effect of an engineering-technology program on high school students' technological thinking disposition and engineering attitude. To achieve this purpose, the question were as follows. 1) How does the engineering-technology program affect high school students' technological thinking disposition? 2) How does the engineering-technology program affect high school students' engineering attitude? For this study, the program was progressed from May to Aug in 2016. The data were collected from 138 D high school students which is located in Daejeon, Korea. For the statistical treatment of data, a Window SPSS-22 are used and significance level of .05 was established prior to data treatment. The results of this study were as follows: First, after participate in engineering-technology program was significant effect on the technological curiosity disposition, technological creativity and expression disposition, technological operating disposition, technological planning and reflecting disposition but no significant effect on the technological analyze disposition, technological problem identifying resolving disposition. Second, after participate in engineering-technology program, there was significant effect on the interests in engineering, the perceptions of creativity in engineering but no significant effect on the perceptions of importance in engineering.

• Journal of the Korean Ceramic Society
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• v.47 no.2
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• pp.113-116
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• 2010

The silica coated $Fe_3O_4$ nanoparticles have been synthesized using a micro-emulsion method. The $Fe_3O_4$ nanoparticles with the sizes 6 nm in diameter were synthesized by thermal decomposition method. Hydrophobic $Fe_3O_4$ nanoparticles were coated silica using surfactant and tetraethyl orthosilicated (TEOS) as a $SiO_2$ precursor. Shell thickness of silica coated $Fe_3O_4$ can be controlled (11~20 nm) through our synthetic conditions. The $Fe_3O_4$ and silica coated $Fe_3O_4$ nano powders were characterized by transmission electron microscopy (TEM), x-ray diffraction (XRD) and vortex magnetic separation (VMS).

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.72-79
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• 2018

Hybrid F2HX surfactants bearing a sulfate moiety and both hydrocarbon and fluorocarbon chains were prepared by the reaction of alkyl glycidyl ethers with fluoro-alcohol, and subsequent sulfation. The fluorocarbon number in F2HX was fixed at the shortest number possible (i.e., 2), while the hydrocarbon number (X) in the second chain was varied between 2, 4, 6, and 8. Their surface-active properties and emulsion stabilities were systematically estimated as a function of the X. Among them, F2H8 exhibited the optimal surfactant performance, which was comparable to previously reported surfactants and it was successfully applied in the emulsion polymerization of vinylidene fluoride.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.794-799
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• 2004

Recent paradigm in technology shifts from object-based technology to environment-based technology. Issue here is interaction among humans and the world around humans, which is natural and artificial "space." Holistic interactions based on "Mom (embodiment)" suggest a good starting point for exploring this issue. Soft engineering, "Mom," holistic interactions, tangible space, ubiquitous computing, science of emotion, and interactive media are key concepts in interactive technology. Interactive tangible media "iT_Media" is proposed to explore and synthesize these ideas. Interactive technology initiative (ITI) is an interdisciplinary research group to search for the proper technology and the proper way of implementing technology: "interactive technology" or "soft engineering." Some experimental activities conducted by ITI are presented in this session, "Interactive Technology."

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.4 no.2
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• pp.241-248
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• 2004

Recent paradigm in technology shifts from object-based technology to environment-based technology. Issue here is interaction among humans and the world around humans. The world we consider includes natural and artificial "space." Interactive technology, which explore holistic interactions based on "Mom (embodiment)," suggests a good starting point for exploring this issue. Soft engineering, "Mom," holistic interactions, tangible space, ubiquitous computing, science of emotion, and interactive media are key concepts in interactive technology. Interactive tangible media "iT_Media" is proposed to explore and synthesize these ideas. Interactive technology initiative (ITI) is an interdisciplinary research group to search for the proper technology and the proper way of implementing technology: "interactive technology" or "soft engineering." Some experimental activities conducted by ITI are presented in this paper.tal activities conducted by ITI are presented in this paper.

• Journal of Engineering Education Research
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• v.20 no.6
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• pp.68-75
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• 2017

This study has a purpose to analyse changes in perception and image about engineering and technology of students who participated in the engineering camp. To achieve this objective, the questions were as follows. 1) What about participants' image difference for engineering before and after participating the engineering camp 2) What about participants' image difference for technology before and after participating the engineering camp. For this study, the program was progressed from Aug in 2017 and the data was collected from 88 students, middle school seniors and high school freshmen. The results of this study were as follows: First, secondary students perceived 'valuable(6.74)', 'meaningful(6.73)', 'rich(6.40)', 'collaborative(6.42)', 'nice(6.22)' as high image rank of the positive response for engineering. On the other hand, 'complex(3.59)', 'labored(3.80)', 'hard(4.66)', 'dangerous(4.48)', 'cold(4.86)' were perceived as low image rank of the negative response for engineering. We can realize that they generally has the image that engineering is valuable, meaningful and nice but also labored, complex and hard. The students who participated in the engineering camp showed the greatest difference in 'complex - simple' and 'dangerous - safe' engineering categories before and after the camp, followed by 'cold - hot', 'labored - easy', and 'hard - soft', respectively. Second, secondary students perceived 'meaningful(6.58)', 'valuable(6.55)', 'wide(6.38)', 'nice(6.37)', 'strong(6.25)' as high image rank of the positive response for technology. On the other hand, 'complex(3.85)', 'labored(3.93)', 'hard(4.62)', 'dangerous(4.72)', 'cold(5.05)' were perceived as low image rank of the negative response for technology. The students who participated in the engineering camp had the big change in 'hard - soft' technology category before and after the camp, followed by 'complex - simple', 'labored - easy', 'theoretical - practical' and 'dangerous - safe', respectively. We can see that the negative images for technology which were complex, labored, dangerous, theoretical was improved with positive image such as simple, easy, safe and practical, after conducting the engineering camp. In conclusion, both image recognitions for engineering and technology have improved after the camp. It means that interesting and entertaining engineering-technology program can boost interests in engineering and technology which felt difficult, so that images about them can be turned out positive. Also, it is possible to reduce avoidance of natural science and engineering subjects, as part of the purpose of training creative talents in science and engineering, so it can be said that the engineering camp is highly meaningful because it can lead students into the field of science and engineering.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.2
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• pp.223-229
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• 2024

Laser-induced plasmonic sintering of metal nanoparticles (NPs) holds significant promise as a technology for producing flexible conducting electrodes. This method offers immediate, straightforward, and scalable manufacturing approaches, eliminating the need for expensive facilities and intricate processes. Nevertheless, the metal NPs come at a high cost due to the intricate synthesis procedures required to ensure long-term reliability in terms of chemical stability and the prevention of NP aggregation. Herein, we induced the self-generation of metal nanoparticles from Ag organometallic ink, and fabricated highly conductive electrodes on flexible substrates through laser-assisted plasmonic annealing. To demonstrate the practicality of the fabricated flexible electrode, it was configured in a mesh pattern, realizing multi-touchable flexible touch screen panel.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.357-357
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• 2002

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.613-613
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• 2003