• 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.

• 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.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.10a
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• pp.140-140
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• 2009

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1847-1852
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• 2003

Ultrasonic motors have many excellent performances. A variety of ultrasonic motors has been developed and used as an actuator in motion control systems. However, this motor has nonlinear characteristics. Therefore, it is difficult to achieve the precise position control system incorporating with the ultrasonic motor. This paper describes a position control scheme for traveling-wave type ultrasonic motor using a pseudo-derivative control with feedforward gains (PDFF) controller designed by the coefficient diagram method (CDM). The PDFF control system satisfies both the tracking and regulation performances, which are the most important for the precise position control system. The CDM is shown to be an efficient and simple method to design the parameters of PDFF controller. The effectiveness of the proposed control system is demonstrated by experiments.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.8
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• pp.787-793
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• 2012

This paper introduces the autonomous vehicle Pharos, which participated in the 2010 Autonomous Vehicle Competition organized by Hyundai-Kia motors. PHAROS was developed for high-speed on/off-road unmanned driving avoiding diverse patterns of obstacles. For the high speed traveling up to 60 km/h, long range terrain perception, real-time path planning and high speed vehicle motion control algorithms are developed. This paper describes the major hardware and software components of our vehicle.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.6
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• pp.743-748
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• 2022

The initial operation stability of hydrogen-fueled, solid oxide fuel cell with Ni thin-film anode fabricated by direct current sputtering was evaluated in terms of electrochemical properties such as peak power density, open circuit voltage, overpotential, and alternating current impedance at 500℃. Hydrogen and air were used as anode fuel and cathode fuel, respectively.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2682-2686
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• 2003

Recent paradigm in technology shifts from object-based technology to environment-based technology. Issue here is interaction among human, machines, and environment. This requires new interpretations for the space among them. Holistic interactions based on “Mom (embodiment)” suggest a good starting point for this endeavor. The past, present, future of technology are presented in terms of technology’s fundamental virtue: “humanizing technology” or “technology serving human.” 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 organized session, “Interactive Technology.” Metatechnology, soft engineering, “Mom (embodiment),” holistic interactions, tangible space, and ubiquitous computing are key concepts in interactive technology.

• Polymer Science and Technology
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• v.17 no.6
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• pp.763-774
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• 2006

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2487-2495
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• 2018

Inspired by the specific amino acid sequence Asn-Pro-Ala (NPA) of water channel aquaporins (AQPs), we fabricated polyamide (PA) nanofiltration (NF) membranes by introducing reduced glutathione (GSH) in interfacial polymerization (IP) method. Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectrometry (XPS), scanning electron microscope (SEM), atomic force microscopy (AFM), zeta potential and static water contact angle measurement were employed to characterize the chemical composition, morphology, electronegativity and hydrophilicity of the NF membranes. The water flux of GSH/PIP-TMC NF membrane reached $32.00L\;m^{-2}h^{-1}$ at 0.2 MPa, which was approximately twice than that of pristine PIP-TMC NF membrane when the ratio of GHS to piperazidine (PIP) was 40% during IP process. More water channels were built as GSH was embedded into PA layer. The fabricated NF membranes also took on potent rejection for dyes and $Na_2SO_4$. This study presents a simple and facile method to simulate water channels-based biological materials which may find potential application in water treatment.

• Macromolecular Research
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• v.14 no.6
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• pp.659-662
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• 2006