• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.9
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• pp.729-734
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• 2000

Recently, Very Large Scale Integrated (VLSI) circuit & deep-submicron bulk Complementary Metal Oxide Semiconductor(CMOS) devices require gate electrode materials such as metal-silicide, Titanium-silicide for gate oxides. Many previous authors have researched the improvement sub-micron gate oxide quality. However, few have reported on the electrical quality and reliability on the ultra thin gate oxide. In this paper, at first, I recommand a novel shallow trench isolation structure to suppress the corner metal-oxide semiconductor field-effect transistor(MOSFET) inherent to shallow trench isolation for sub 0.1${\mu}{\textrm}{m}$ gate oxide. Different from using normal LOCOS technology deep-submicron CMOS devices using novel Shallow Trench Isolation(STI) technology have a unique"inverse narrow-channel effects"-when the channel width of the devices is scaled down, their threshold voltage is shrunk instead of increased as for the contribution of the channel edge current to the total channel current as the channel width is reduced. Secondly, Titanium silicide process clarified that fluorine contamination caused by the gate sidewall etching inhibits the silicidation reaction and accelerates agglomeration. To overcome these problems, a novel Two-step Deposited silicide(TDS) process has been developed. The key point of this process is the deposition and subsequent removal of titanium before silicidation. Based on the research, It is found that novel STI structure by the SEM, in addition to thermally stable silicide process was achieved. We also obtained the decrease threshold voltage value of the channel edge. resulting in the better improvement of the narrow channel effect. low sheet resistance and stress, and high threshold voltage. Besides, sheet resistance and stress value, rms(root mean square) by AFM were observed. On the electrical characteristics, low leakage current and trap density at the Si/SiO$_2$were confirmed by the high threshold voltage sub 0.1${\mu}{\textrm}{m}$ gate oxide.

• Journal of information and communication convergence engineering
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• v.6 no.3
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• pp.305-309
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• 2008

This paper presents an innovative prototype of a new conceptual electromagnetic induction eddy current based fluid heating appliance using voltage-fed quasi resonant zero voltage soft switching PWM high-frequency inverter using IGBTs, which can operate at a constant frequency variable power regulation scheme. The promising simple high efficient low noise inverter type electromagnetic induction eddy current based pipeline fluid heating appliance is proposed for saturated steam generator, superheated steam generator, hot water and hot air producer, metal catalyst heating for exhaust gas cleaning in engine. Under these technological backgrounds, a novel electromagnetic induction eddy current Dual Packs Heater(DPH) based pipeline fluid heating incorporates thin metal layer type package for continuous fluid heating appliances applying two types of voltage-fed quasi load resonant ZVS-PWM high frequency inverter. The unique features of a novel electromagnetic induction eddy current DPH based continuous pipeline fluid heating appliance is illustrated on the basis of simulation and discussed for the steady state operating characteristics and experimental results.

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.208-211
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• 2000

This paper describes the design of a CMOS frequency synthesizer using programmable frequency divider with novel architecture. A novel architecture of programmable divider can be producted all of integer-N and fabricated by 0.65$\mu\textrm{m}$ 2-poly, 2-metal CMOS technology. Frequency synthesizer is simulated by 0.25$\mu\textrm{m}$ 2-poly, 5-metal CMOS technology. This circuit has settling time of 1.5${\mu}\textrm{s}$ and power consumption of 70㎽. Operating frequency of the frequency synthesizer is 820MHz∼l㎓ with a 2.5V supply voltage.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.12
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• pp.1942-1949
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• 2004

SLA(Scanned Linear Array) is a portable display unit for implementing next-generation virtual realities, utilizes a design that light generated by a line of LEDs is reflected from the rapidly oscillating mirror to generate a raster display. Reaction forces generated by the motions of the mirror and counter-balance mass cancel each other at the device base, reducing vibration. Metal leaf springs have been extensively applied in such portable units. Magnetic springs have been developed and adopted that can replace the metal spring and can avoid many disadvantages of metal springs. We model and analyze the dynamics of the structure with magnetic springs and present the simulation and experimental analysis results, which can be utilized for identifying and eliminating possible problem sources in removing shaking forces and moments, and oscillating the mirror at the required amplitude and frequency. Finally, we present the improved novel magnetic actuator model which can be applied in portable display units.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.35-35
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• 2011

The design and preparation of novel dye rotaxanes have gained much interest recently, since such structure usually exhibits peculiar spectral and optical changes. In spite of the promising results to date, increasing pressure remains to develop novel supramolecular structures based on stimuli-responsive systems. This presentation covers the study of inclusion complexes of cyclodextrins and various chromophores, with an emphasis on our most recent outcome of anisotropic hydrogel. In this system, physical gelation prepared from simple mixture of CD and a azo dye is completed through specific host-guest interaction. The obtained hydrogel exhibits respective morphological transitions based on supramolecular assembly and dissociation, leading to either precipitation or a sol-to-gel transition. It can identify different classes of metal ions, and, among them, naked-eye differentiation of lead ion is possible due to the coordination-induced unthreading of dye molecules. Accompanying structural changes were verified by numerous characterization techniques, including 2D-ROESY, HR-MAS, UV-Visible absorption, small-angle X-ray scattering, and induced circular dichroism measurements. Such properties discussed here will find useful in analytical applications, such as metal ion sensing and removal applications.

• ETRI Journal
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• v.31 no.6
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• pp.778-783
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• 2009

To fabricate uniform and reliable thin gold stripes that provide low-loss optical waveguides, we developed a novel liftoff process placing an additional $SiN_x$ layer under conventional photoresists. By patterning a photoresist and over-etching the $SiN_x$, the photoresist patterns become free-standing structures on a lower-cladding. This leads to uniform metal stripes with good reproducibility and effectively removes parasitic structures on the edge of the metal stripe in the image reversal photolithography process. By applying the newly developed process to polymer-based gold stripe waveguide fabrication, we improved the propagation losses about two times compared with that incurred by the conventional image-reversal process.

• Mycobiology
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• v.48 no.4
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• pp.296-303
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• 2020

Three yeast strains (Hue-1, Hue-8, and Hue-19) with strong heavy metal tolerance were isolated from mangosteen from Hue city, Vietnam. They exhibited identical phenotype and phylogeny. Sequence analysis of the D1/D2 region of the LSU rRNA gene and the internal transcribed spacer (ITS) region demonstrated that the closest relative of these strains is Papiliotrema sp. with 2.12% and 3.55-3.7% divergence in the D1/D2 domain, and ITS domain, respectively. Based on the physiological, biochemical, and molecular data, the three strains belong to a novel species of Papiliotrema genus, for which the name Papiliotrema huenov sp. nov. is proposed. These strains are highly tolerant of heavy metals compared to other yeasts, being able to grow in the presence of 2 mM Pb (II), 2 mM Cd (II), and up to 5 mM Ni (II), but no growth was observed in the presence of 1 mM As (III).

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.323-329
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• 2018

In Escherichia coli, the transcription of genes related to metal homeostasis is activated by the presence of target metals. The promoter regions of those genes can be fused with reporter genes to generate whole-cell bioreporters (WCBs); these organisms sense the presence of target metals through reporter gene expression. However, the limited number of available promoters for sensing domains restricts the number of WCB targets. In this study, we have demonstrated an alternative method to generate novel WCBs, based on the notion that since the sensing mechanisms of WCBs are related to metal transportation systems, their properties can be modulated by disrupting metal homeostasis. Mutant E. coli strains were generated by deleting the znt-operon genes zntA, which encodes a zinc-export protein, and zntR, which encodes a znt-operon regulatory protein, to investigate the effects on the metal-sensing properties of WCBs. Deletion of zntA increased the sensitivity but abolished the selectivity of cadmium-sensing WCBs, whereas arsenic-sensing WCBs gained sensitivity toward cadmium. When zntR was deleted, cadmium-sensing WCBs lost the ability to detect cadmium, and this was recovered by introducing exogenous zntR. In addition, the metal-binding site of ZntR was genetically engineered to modulate metal selectivity. This study provides a valuable platform for the development of novel E. coli-based WCBs.

• Journal of Korea Multimedia Society
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• v.15 no.12
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• pp.1442-1448
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• 2012

The problem of Metal Area Segmentation (MAS) in X-ray CT images is a very hard task because of metal artifacts. This research features a practical yet effective method for MAS in X-ray CT images that exploits both projection image and reconstructed image spaces. We employ the Relevant Neighbor Area (RNA) idea [1] originally developed for projection image inpainting in order to create a novel feature in the projection image space that distinctively represents metal and near-metal pixels with opposite signs. In the reconstructed result of the feature image, application of a simple thresholding technique provides accurate segmentation of metal areas due to nice separation of near-metal areas from metal areas in its histogram.

• Proceedings of the Korean Vacuum Society Conference
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• 2009.02a
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• pp.176.1-176.1
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• 2009