• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.97-100
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• 2003

Recently, the generators for wind turbine have been manufactured with high output power such like MW class machine in order to reduce the generation cost and to increase the energy efficiency. At the same time, direct-driven generators for wind turbine have been developed and researched, which have easy maintenance and high efficiency by simplification the system through the removal of the gear box. In this paper, at first, the advantage and disadvantage between the direct-driven generator system and conventional indirect-driven system are compared. And secondly, the permanent magnet generator (PMG) for wind turbine has been rapidly improved to cope with the recent trend which requires the high power output Per one machine and the convenience for maintenance, and the PMG is adequate for direct driven system and suitable for high-efficiency and light weight. So, the characteristics and technical trend of the PMG for wind turbine is examined. At last, a suitable technical trend for development of the permanent magnet generator for wind turbine is proposed.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.48-48
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• 2011

We have developed a chemically-driven top-down approach using vapor phase HCl to form various GaN nanostructures and successfully demonstrated dislocation-free and strain-relaxed GaN nanostructures without etching damage formed by a selective dissociation method. Our approach overcomes many limitations encountered in previous approaches. There is no need to make a pattern, complicated process, and expensive equipment, but it produces a high-quality nanostructure over a large area at low cost. As far as we know, this is the first time that various types of high-quality GaN nanostructures, such as dot, cone, and rod, could be formed by a chemical method without the use of a mask or pattern, especially on the Ga-polar GaN. It is well known that the Ga-polar GaN is difficult to etch by the common chemical wet etching method because of the chemical stability of GaN. Our chemically driven GaN nanostructures show excellent structure and optical properties. The formed nanostructure had various facets depending on the etching conditions and showed a high crystal quality due to the removal of defects, such as dislocations. These structure properties derived excellent optical performance of the GaN nanostructure. The GaN nanostructure had increased internal and external quantum efficiency due to increased light extraction, reduced strain, and improved crystal quality. The chemically driven GaN nanostructure shows promise in applications such as efficient light-emitting diodes, field emitters, and sensors.

• Analytical Science and Technology
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• v.30 no.2
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• pp.89-95
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• 2017

The thermodynamic functions for the binding of the peptide Substance P (SP) on the surface of lipid vesicles made of various types of lipids were obtained by using isothermal titration calorimetry. The reaction enthalpies measured from the experiments were -0.11 to $-4.5kcal\;mol^{-1}$. The sizes of the lipid vesicles were measured with dynamic light scattering instrument in order to get the correlation between the reaction enthalpies and the vesicle sizes. The bindings of SP on the lipid vesicles with diameter of 37 to 108 nm were classified into the enthalpy-driven reaction or the entropy-driven reaction according to the size of the lipid vesicles. For the enthalpy-driven binding reaction, the significance of the electrostatic interactions between SP and lipid molecules was affirmed from the experimental results of the DMPC/DMPG/DMPH and DMPC/DMPS/DMPH vesicles as well as the importance of the hydrophobic interactions between hydrophobic groups of SP and lipid molecules.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.433-438
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• 2012

LED is expected as an environmentally friendly next generation light source with its good reliability and long lifetime. In this paper, we propose the PV-Battery Driven LED Security Lighting using the LabVIEW program. The remote monitoring is a program for monitoring the voltage and current that made from PV-Battery Driven LED security lighting in remote area. The main subject of this paper is about making the more useful monitoring program to get and save the data from LED Security Lighting. We develop a prototype of the proposed system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.440-441
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• 2006

We have studied the narrow viewing angle liquie crystal displays (LCDs) using a hybrid aligned nematic liquid crystal (LC) cell driven by a fringe field. The device using a LC with positive dielectric anisotropy has a relatively low transmittance. This paper describes how to improve light efficiency by optimizing electrode structure. The results show that the device exhibits a high transmittance of 90%, low driving voltage and narrow viewing angle less than $20^{\circ}$ along horizontal direction which is highly effective for private display application.

• Asia Pacific Journal of Corpus Research
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• v.4 no.1
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• pp.25-42
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• 2023

The number of studies on data-driven learning (DDL) has increased in recent years, and DDL's overall effectiveness as an L2 (second language) teaching methodology has been reported to be high. However, the degree of its effectiveness in grammar instruction, particularly for the goal of correcting errors in L2 writing, is still unclear. To provide guidelines for focused grammar instruction with DDL in the Japanese classroom setting, we aimed to identify the typical grammatical errors made by Japanese learners in the Cambridge Learner Corpus First Certificate in English (CLC FCE) dataset. The results revealed that three error types (nouns, articles, and prepositions) should be addressed in DDL grammar instruction for Japanese English as a foreign language (EFL) learners. In light of the findings, pedagogical implications and suggestions for future DDL research and practice are discussed.

• Science of Emotion and Sensibility
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• v.23 no.1
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• pp.57-68
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• 2020

This research investigates how digital design agencies and client companies incorporate design thinking-a human-centered approach to solving difficult problems-into their website development processes. Based on a literature review on the design-thinking-driven web development process, multiple case studies of award-winning website projects were performed by in-depth interviews with key practitioners. Through analyses of these cases, their user-centered approaches for website innovation were identified according to the following four phases: web planning (discovery and defining phases) and web design and development (development and delivery phases). Moreover, distinct approaches of design thinking practices were identified according to two website types: a brand promotion website with a killer brand storytelling approach; and a service channel website with a strategic UI/UX-driven approach. Next, the key success drivers of these website projects were suggested in light of the typical themes of design thinking (i.e., human centeredness, research based, context awareness, and collaboration). Some practical limitations were also found in adopting the design-thinking-driven web development process, such as limited research methods and tools, and insufficient prototyping and experimentation. Along with these limitations, it was also discovered that current digital design agencies still face the following challenges in adopting the design-thinking-driven web development process: building a long-term, playful partnership with clients; leveraging decision-makers' design thinking awareness; and coping with limited resources (design thinking practitioners, budgets, and schedules).

• Journal of Sensor Science and Technology
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• v.21 no.5
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• pp.389-393
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• 2012

A chaotic oscillator with light controllability was designed. The proposed chaotic oscillator consists of a photo sensor, two phase clock driven MOS switches, nonlinear function blocks for chaotic signal generation. SPICE circuit analysis using a 0.35 um CMOS process parameters was performed for its chaotic dynamics. And we confirmed that chaotic behaviors of the circuit can be controlled according to light intensity. By SPICE simulation, chaotic dynamics by time waveforms, frequency analysis was analyzed. SPICE results showed that proposed circuit can make various light-controlled chaotic signals.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.119-123
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• 2004

This paper describes low temperature poly-Si (LTPS) TFT system on glass (SOG) technology developed in NEC. High resolution SOG-LCDs such as a 230 ppi reflective type LCD, a 2.5", 333 ppi 2D/3D autostereoscopic LCD, and a 2.1" single voltage driven full integration LCD for mobile applications and a 0.9", XGA light valve for projectors are reviewed from the perspective of the high resolution technologies

• Proceedings of the Microbiological Society of Korea Conference
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• 2008.05a
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• pp.165-165
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• 2008