• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.679-682
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• 2003

We report the suitable SLS (sequential lateral solidification) as a function of laser intensity. Precursor film is changed from 50nm to 100nm and is deposited on glass substrate by PECVD. We can find the suitable SLS length by changing the mask size. In this paper, we present the well-defined grain growth conditions as a function of laser intensity.

• Transactions of the Korean hydrogen and new energy society
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• v.8 no.1
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• pp.43-47
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• 1997

A new type of anode materials in form of nanocrystalline composite powders has been developed that offers the potential for dramatically improved discharge capacity and initial activation rate. The composites are synthesized by ball milling of two components - a major component (basic component) having high hydrogen capacity and a minor component (surface activator) with good electrocatalytic activity. The capacity increase observed by ball milling with surface activator. The ball-milled composite materials are easier to activate than the non ball-milled basic component.

• Steel and Composite Structures
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• v.26 no.5
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• pp.607-620
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• 2018

Vibration analysis of deep curved FG nano-beam has been carried out based on modified couple stress theory. Material properties of curved Timoshenko beam are assumed to be functionally graded in radial direction. Governing equations of motion and related boundary conditions have been obtained via Hamilton's principle. In a parametric study, influence of length scale parameter, aspect ratio, gradient index, opening angle, mode number and interactive influences of these parameters on natural frequency of the beam, have been investigated. It was found that, considering geometrical deepness term leads to an increase in sensitivity of natural frequency about variation of aforementioned parameters.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.308-312
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• 2003

Recently the trend of new materials development is extensively and very actively progressing in the study of physical and chemical characteristics developing a totally new material along with the study field of recently discovered material modifying physically and chemically characteristics. Among these fields of studies, one method to improve adaptation of inorganic material is the study of mesoporous materials. The most general way to synthesize mesoporous materials is to mold the very systematical mesopore into a corpuscle by using templates(omitted)

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.5
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• pp.138-146
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• 2002

The new type of vibration reduction material far an automotive interior, which is spray-type liquid material, is developed in this study The new material has better damping property and lower mass density than other damping materials, for example asphalt sheet. It can be sprayed by an automatic robot, so it is expected to improve productivity and cut down manpower. And it solves a poor adhesion problem and makes an automotive to be lightweight by optimizing spray process. So, It is a next generation automotive vibration reduction material. In this paper, the chemical process for making the new damping materials is described. And then, the damping properties of the vibration reduction materials are analyzed by modal testing of damping treatment specimens. The new vibration reduction materials have good damping properties than asphalt sheet in the experimental results.

• ETRI Journal
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• v.30 no.5
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• pp.644-652
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• 2008

In this paper, a low-power CMOS interface circuit is designed and demonstrated for capacitive sensor applications, which is implemented using a standard 0.35-${\mu}m$ CMOS logic technology. To achieve low-power performance, the low-voltage capacitance-to-pulse-width converter based on a self-reset operation at a supply voltage of 1.5 V is designed and incorporated into a new interface circuit. Moreover, the external pulse signal for the reset operation is made unnecessary by the employment of the self-reset operation. At a low supply voltage of 1.5 V, the new circuit requires a total power consumption of 0.47 mW with ultra-low power dissipation of 157 ${\mu}W$ of the interface-circuit core. These results demonstrate that the new interface circuit with self-reset operation successfully reduces power consumption. In addition, a prototype wireless sensor-module with the proposed circuit is successfully implemented for practical applications. Consequently, the new CMOS interface circuit can be used for the sensor applications in ubiquitous sensor networks, where low-power performance is essential.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.565-573
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• 2009

Even in case of new materials, materials that are not only harmless for the current global environment but also have high-performance and high-function are sought-after in consideration of the global environmental problems. Moreover, in construction areas where a large amount of cement and concrete are used, the establishment of the recycling technology or transformation into resources and energy materials are being put in place. And also, in a situation where the slow and relaxed city and rural life have a high priority, the need for cement and concrete as environmentally friendly new materials that best suit the emotions in human beings is on the rise and a new way to make good use of cement and concrete as new materials in construction technology should be sought. The recently introduced functional and environmentally friendly concrete is aimed at enhancing health through the adjustments of the body biorhythm using far-infrared. Minerals that contain a great amount of the elements with the frequent occurrence of the infrared among earth minerals and concrete are mixed to use structures or finishing materials, which will tackle the issues of smells, mold and corrosion.

• Korean Journal of Metals and Materials
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• v.46 no.4
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• pp.241-248
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• 2008

Gas turbine blades serviced for a period are usually repaired for reuse via "rejuvenation processes" including fluoride ion cleaning, brazing or welding, and recoating. Among these processes, the welding process is applied to rebuilt damaged parts of the blade in which welding materials being mostly Ni base superalloy are supplied in the form of powder or wire. When powder is used in the welding process, the uniform supply of powder is a very important factor for the uniformity of welding. According to our experience, the uniformity was very poor with the powder supply system only utilizing pressurized air flow. A new powder supply system was developed in which powder is supplied via air flow and simultaneously mechanically. The welding uniformity was much improved with this new system. In this study, the microstructure and mechanical properties of welded parts obtained from several kinds of powder using the new powder supply system were characterized.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.100-100
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• 2016

Among various two-dimensional (2D) materials, 2D semiconductors and insulators have attracted a great deal of interest from nanoscience community beyond graphene, due to their attractive and unique properties. Such excellent characteristics have triggered highly active researches on 2D materials, such as hexagonal boron nitride (hBN), molybdenum disulfide (MoS2), and tungsten diselenide (WSe2). New physics observed in 2D semiconductors allow for development of new-concept devices. Especially, these emerging 2D materials are promising candidates for flexible and transparent electronics. Recently, van der Waals heterostructures (vdWH) have been achieved by putting these 2D materials onto another, in the similar way to build Lego blocks. This enables us to investigate intrinsic physical properties of atomically-sharp heterostructure interfaces and fabricate high performance optoelectronic devices for advanced applications. In this talk, fundamental properties of various 2D materials will be introduced, including growth technique and influence of defects on properties of 2D materials. We also fabricate high performance electronic/optoelectronic devices of vdWH, such as transistors, memories, and solar cells. The device platform based on van der Waals heterostructures show huge improvement of devices performance, high stability and transparency/flexibility due to unique properties of 2D materials and ultra-sharp heterointerfaces. Our work paves a new way toward future advanced electronics based on 2D materials.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2003.10a
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• pp.80-81
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• 2003