• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.329-329
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• 2016

Large-area graphene films produced by means of chemical vapor deposition (CVD) are polycrystalline and thus contain numerous grain boundaries that can greatly degrade their performance and produce inhomogeneous properties. A better grain boundary engineering in CVD graphene is essential to realize the full potential of graphene in large-scale applications. Here, we report a defect-selective atomic layer deposition (ALD) for stitching grain boundaries of CVD graphene with ZnO so as to increase the connectivity between grains. In the present ALD process, ZnO with hexagonal wurtzite structure was selectively grown mainly on the defect-rich grain boundaries to produce ZnO-stitched CVD graphene with well-connected grains. For the CVD graphene film after ZnO stitching, the inter-grain mobility is notably improved with only a little change in free carrier density. We also demonstrate how ZnO-stitched CVD graphene can be successfully integrated into wafer-scale arrays of top-gated field effect transistors on 4-inch Si and polymer substrates, revealing remarkable device-to-device uniformity.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.47-50
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• 2003

Hot-forging Process and die design was made for a large-scale compressor wheel of Ti-6Al-4V alloy with 2-D FE analysis. The design integrated the geometry-controlled approach and dynamic materials modelling(DMM). In order to obtain the processing contour map of Ti-6Al-4V alloy based on DMM, compression tests were carried out in the temperature range of 915$^{\circ}C$ to 1015$^{\circ}C$ and the strain range of 10$\^$-3/s$\^$-1/ to 10s$\^$-1/. In the die design of the compressor wheel using the rigid-plastic FE analysis, forging dimensional accuracy, the capacity of the forging machine and defect-free forging were considered as main design factors. The microstructure of hot forged wheel using the designed die showed a typical alpha-beta structure without forging-defects.

• Journal of Korea Port Economic Association
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• v.20 no.1
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• pp.153-172
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• 2004

With swelling of Chinese Economic scale, the competitive environment is swinging over the north-east Asia countries, Korea, Japan, China, and Taiwan. As the result of this circumstance, each countries in this area has been reformed their industries. According to the expanding in ocean logistic. The trends of competition on Hub port is looking forward much more severe year after year to preoccupy in logistics competitive within this Area. On the other hand, considering competitive environment & swelling of Chinese Economic scale, the structural reforms are imperative in korea. Korea have to convert the traditional sects into new high added value sects. In these trends, provincial government also should look for the plan for reinforcement of Regional competitiveness. The focus of this study is to look for the reinforcement methods on regional competitiveness of Gyeongnam Provincial Government. First, competitive industries in Gyeongnam, and second, Masan Free Trade Zone will be surveyed from data. Finally, the effects of New Hub port developing in Pusan-Jinhae will be discussed.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.541-546
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• 1998

The objective of this research is to observe the actual response of low-rise nonseismic moment-resisting infilled reinforced concrete frame subjected to varied levels of earthquake ground motions. First of all, the reduction scale for the model was determined as 1 : 5 considering the capacity of the shaking table to be used. This model was, then, subjected to the shaking table motions simulating Taft N21E component earthquake ground motions, whose peak ground accelerations(PGA`s) were modified to 0.12g, 0.2g, 0.3g, and 0.4g. The global behavior and failure mode were observed. The lateral accelerations and displacements at each story and local deformations at the critical portions of structure were measured. Before and after each earthquake simulation test, free vibration tests were performed to find the changes in the natural period of the model.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.1
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• pp.34-41
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• 2005

An experimental study of molecular motions on a liquid-vapor interface is limited due to micro-scale characteristics of a system with an angstrom or a nanometer size Therefore, in recent, many studies for micro-scale systems have been conducted by a computer simulation because it is free from experimental limitations. In this study, through the molecular dynamic (MD) method. molecular behavior was clarified on a liquid-vapor interface and a criterion to distinguish between liquid and vapor was suggested by a potential energy and the number of neighboring molecules. At an interface. the potential energy of a molecule was increased but the number of neighboring molecules was decreased when the molecule moved into a vapor region from a liquid region, and vice versa.

• Science of Emotion and Sensibility
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• v.4 no.1
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• pp.33-42
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• 2001

The purpose of this study was to construct the scale in fashion sensibility. Base on the Fashion Magazines and free word association method, 919 affective words were condensed into 36 semantic differential bi-polar scales. 128 male and 128 female in Pusan rated their Fashion Sensibility by 87 kinds of costume samples from photographs divided into four types according to color, detail and trimming, pattern, textile. The obtained data analyzed by Cronbach ${\alpha}$, Factor analysis, Cluster analysis to consider of the reliability, tranquility, and resemblance among the meaning. The results of the analysis, it was found cleary that aesthetics, maturity character, and femininity masculinity etc were consisted of Fashion Sensibility and 25 item of affective words of Fashion Sensibility and 25 item of affective words of Fashion Sensibility were constructed.

• Journal of the Korea Institute of Military Science and Technology
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• v.7 no.4 s.19
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• pp.138-145
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• 2004

Experimental study was conducted on cylindrical supersonic diffuser in order to investigate the effects of the ratios of diffuser area to nozzle throat area (Ad/At), diffuser area to nozzle exit area (Ad/Ae), nozzle exit area to its throat area (Ae/At), and diffuser length to its diameter (L/D), the free volume of vacuum chamber, and the relative distance between nozzle exit and diffuser inlet on the diffuser performance. The study showed that the minimum diffuser starting pressure (Po/Pa)st increased monotonically with increase in (Ad/At) as predicted by the normal shock and momentum theory models and the volume of vacuum chamber affected vacuum pressure level during diffuser operation at lower value of (Ad/Ae). The results of this investigation will be utilized in the design of real-scale high-altitude simulation test facility.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.6
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• pp.1185-1194
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• 1997

It is necessary to control the frame memory to capture, edit and display images. This paper presents the free-scale image capture processor size of which is user-defined, compared to the conventional image capture processor size of which is fixed 1/2, 1/4 and full size. User-defined scale data is fed into this system, which generates the gating pulses and gates the inputted image data. This system also controls the 4M DRAM instead of frame meamory. And stored gated image data are displayed on the TV monitor. We designed the scalable image capture parts and DRAM controller with ACTEL FPGAs, simulated the circuits with Viewlogic and fusing ACTEL A1020B chips. We confirmed the whole operation with beadboard which composed of "Philips TV Chipset" and designed FPGA chips.PGA chips.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.532-537
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• 2007

Nano imprint lithography(NIL) is a cost-efficient, high-throughput processing technique to transfer nano-scale patterns onto thin polymer films. Polymers used as the resist include UV cured resins as well as thermoplastics such as polymethyl-methacrylate(PMMA). In this study, an analytic investigation was performed for the NIL process of transferring nano scale patterns onto polymeric films. Process optimization calls for a thorough understanding of resist flow during the process. We carried out 2D and 3D numerical analyses of resist flow during NIL process. The simulation incorporated continuum-hypothesis and the effects of surface tension were taken into account. For a more effective prediction of free surface, fixed grid scheme with the volume of fluid (VOF) method were used. The simulation results were verified with experimental results qualitatively. And the parametric study was performed for various process conditions.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.4
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• pp.104-111
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• 2001

The toolpath generation for 3D shaped parts with adaptive isocurve is more precise than existing methods, and the machining time can be reduced. Whether adaptive isocurves are inserted or not is determined by the surface shape, but the number of curves inserted and the total path length vary with initial step lengths. In this paper, therefore, by introducing the concept of the scale factor into the initial path interval ; toolpath was regenerated.