• BMB Reports
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• v.41 no.2
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• pp.126-131
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• 2008

The folding of aptamer immobilized on an Au electrode was successfully detected using label-free electrochemical methods. A thrombin binding DNA aptamer was used as a model system in the presence of various monovalent cations. Impedance spectra showed that the extent to which monovalent cations assist in folding of aptamer is ordered as $K^+$ > $NH_4^+$ > $Na^+$ > $Cs^+$. Our XPS analysis also showed that $K^+$ and $NH_4^+$ caused a conformational change of the aptamer in which it forms a stable complex with these monovalent ions. Impedance results for the interaction between aptamer and thrombin indicated that thrombin interacts more with folded aptamer than with unfolded aptamer. The EQCM technique provided a quantitative analysis of these results. In particular, the present impedance results showed that thrombin participates a folding of aptamer to some extent, and XPS analysis confirmed that thrombin stabilizes and induces the folding of aptamer.

• Journal of Life Science
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• v.9 no.1
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• pp.76-83
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• 1999

Mammalial expression vectors containing GRP94, BiP, ERp72, and PDI, were introduced into FRTL5 cells. Transfected cells were selected by neomycin resistance for exogenously overexpressed proteins in the ER. The use of a reducible cross-linker, DSP, markedly improved the ability to detect noncovalent interactions of PDI, BiP and GRP94 with newly-synthesized thyroglobulin. Under normal conditions, GRP94 was found to associate transiently with early Tg folding intermediates, displaying interaction kinetics similar to those reported for another ER chaperones of BiP.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3521-3524
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• 2010

MTH1880 is a hypothetical protein derived from Methanobacterium thermoautotrophicum, thermophilic methanogen. The solution structure determined by NMR spectroscopy showed that it has a novel $\alpha+\beta$-fold with a highly acidic ligand binding pocket. Since MTH1880 maintains its ultra-stable structural characteristics at both high temperature and pressure, it has been considered as an excellent model for studying protein folding. To initiate the structural and folding study of MTH1880 in proving its unusual stability, we performed the site directed mutagenesis and biochemical analysis of MTH1880 mutants. Data from circular dichroism and NMR spectroscopy suggest that the point mutations perturbed the structural stability of protein even though the secondary structure is retained. This study will provide the useful information in understanding the role of participating residues during folding-unfolding process and our result will be used in designing further folding experiments for hyper-thermopile proteins like MTH1880.

• Journal of Fashion Business
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• v.18 no.3
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• pp.134-147
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• 2014

The aim of this study is to create smart wear that brings out the perspective person's individuality and creativity wearing these garments through various interactions. It is intended to build a prototype for a "Shape-folding Dress", which is length-adjustable skirt that responses with the environment of the wearer. In this process, four basic physical properties can be identified with fabric samples selected which are relatively stiff, including fusible interlining, organdy, silk, and ramie. In addition, two types of folding pattern specimens, "Basic Pattern" and "Diamond Pattern", and heat-steam were used to make the specimens so that the correlation could be calculated by recovery rate among flexing, stiffness and tensile properties. As a result, compared to other fabrics, the silk showed low stress to repeat folding and unfolding process, and its recovery rate of elongation deformation was stable without being affected by the different folding types and twice repeated process. In this study, forming a circuit using an Arduino, illuminance sensor, motors, and pulley, the prototype was created with a silk fabric.

• Journal of Conservation Science
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• v.36 no.5
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• pp.351-367
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• 2020

The pigments of three old and new celestial charts folding screens(『Celestial Chart(Folding Screen)』 and 『Old and New Celestial Charts, Eight-Panel Folding Screen』 of National Folk Museum of Korea and 『Koudou-Nanboku-Ryousouseizu』 of National Diet Library of Japan) were analyzed to estimate their dating. It was estimated that the 『Celestial Charts(Folding Screen)』 was painted using traditional pigments from the Joseon dynasty such as azurite, indigo lake, malachite, atacamite, vermilion, iron oxide, cochineal, gamboge, orpiment, lead white, talc and soot. The green and blue colors of the 『Old and New Celestial Charts, Eight-Panel Folding Screen』 and 『Koudou-Nanboku-Ryousouseizu』 were painted using artificial inorganic pigments such as emerald green and ultramarine blue. These pigments were imported from Europe post the mid-19th century. In the 『Old and New Celestial Chart, Eight-Panel Folding Screen』, only artificial inorganic pigments were used for green and blue colors. However in the 『Koudou-Nanboku-Ryousouseizu』, emerald green and atacamite in green color, and ultramarine blue and indigo lake in blue color were used together. Based on both the results of pigment analysis and the study of star charts and inscriptions, the 『Celestial Charts(Folding Screen)』 was painted post mid-18th century. The 『Koudou-Nanboku-Ryousouseizu』 and 『Old and New Celestial Charts, Eight-Panel Folding Screen』 were painted after green and blue artificial pigments were imported in the mid-19th century. The 『Koudou-Nanboku-Ryousouseizu』 in which both traditional and western artificial pigments were used, can be dated earlier than the 『Old and New Celestial Chart, Eight-Panel Folding Screen』.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.11
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• pp.35-42
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• 2004

A CMOS folding ADC with transistor differential pair folding circuit for low power consumption and high speed operation is presented in this paper. This paper explains the theory of transistor differential pair folding technique and many advantages compared with conventional folding and interpolation circuits. A ADC based on transistor differential pair folding circuit uses 16 fine comparators and 32 interpolation resistors. So it is possible to achieve low power consumption, high speed operation and small chip size. Design technology is based on fully standard 0.25${\mu}{\textrm}{m}$ double poly 2 metal n-well CMOS process. A power consumption is 45mW at 2.5V applied voltage and 250MHz sampling frequency. The INL and DNL are within $\pm$0.15LSB and $\pm$0.15LSB respectively. The SNDR is approximately 50dB at 10MHz input frequency.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.4
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• pp.14-23
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• 2011

In this paper, a 7-bit 2GSPS folding/interpolation A/D Converter(ADC) with a Self-Calibrated Vector Generator is proposed. The ADC structure is based on a folding/interpolation architecture whose folding/interpolation rate is 4 and 8, respectively. A cascaded preprocessing block is not only used in order to drive the high input signal frequency, but the resistive interpolation is also used to reduce the power consumption. Based on a novel self-calibrated vector generator, further, offset errors due to device mismatch, parasitic resistors. and parasitic capacitance can be reduced. The chip has been fabricated with a 1.2V 0.13um 1-poly 7-metal CMOS technology. The effective chip area including the calibration circuit is 2.5$mm^2$. SNDR is about 39.49dB when the input frequency is 9MHz at 2GHz sampling frequency. The SNDR is improved by 3dB with the calibration circuit.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.3
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• pp.18-27
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• 2010

In this paper, a 1.2V 7-bit 1GSPS A/D converter with offset self-calibration is proposed. The proposed A/D converter structure is based on the folding-interpolation whose folding rate is 2, interpolation rate is 8. Further, for the purpose of improving the chip performance, an offset self-calibration circuit is used. The offset self-calibration circuit reduce the variation of the offset-voltage，due to process mismatch, parasitic resistor, and parasitic capacitance. The chip has been fabricated with a 1.2V 65nm 1-poly 6-metal CMOS technology. The effective chip area is $0.87mm^2$ and the power dissipates about 110mW at 1.2V power supply. The measured SNDR is about 39.1dB when the input frequency is 250MHz at 800MHz sampling frequency. The measured SNDR is 3dB higher than the same circuit without any calibration.

• Atmosphere
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• v.27 no.2
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• pp.119-131
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• 2017

We present and discuss the Tropopause Folding Turbulence Detection (TFTD) algorithm for the Korean Communication, Ocean, Meteorological Satellite (COMS) which is originally developed for the Tropopause Folding Turbulence Product (TFTP) from the Geostationary Operational Environmental Satellite (GOES)-R. The TFTD algorithm assumes that the tropopause folding is linked to the Clear Air Turbulence (CAT), and thereby the tropopause folding areas are detected from the rapid spatial gradients of the upper tropospheric specific humidity. The Layer Averaged Specific Humidity (LASH) is used to represent the upper tropospheric specific humidity calculated using COMS $6.7{\mu}m$ water vapor channel and ERA-interim reanalysis temperature at 300, 400, and 500 hPa. The comparison of LASH with the numerical model specific humidity shows a strong negative correlation of 80% or more. We apply the single threshold, which is determined from sensitivity analysis, for cloud-clearing to overcome strong gradient of LASH at the edge of clouds. The tropopause break lines are detected from the location of strong LASH-gradient using the Canny edge detection based on the image processing technique. The tropopause folding area is defined by expanding the break lines by 2-degree positive gradient direction. The validations of COMS TFTD is performed with Pilot Reports (PIREPs) filtered out Convective Induced Turbulence (CIT) from Dec 2013 to Nov 2014 over the South Korea. The score test shows 0.49 PODy (Probability of Detection 'Yes') and 0.64 PODn (Probability of Detection 'No'). Low POD results from various kinds of CAT reported from PIREPs and the characteristics of high sensitivity in edge detection algorithm.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.1
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• pp.14-21
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• 2011

A 10b 500MS/s $0.13{\mu}m$ CMOS ADC is proposed for 4G wireless communication systems such as a LTE-Advanced and SDR The ADC employs a calibration-free single-channel folding architecture for low power consumption and high speed conversion rate. In order to overcome the disadvantage of high folding rate, at the fine 7b ADC, a cascaded folding-interpolating technique is proposed. Further, a folding amplifier with the folded cascode output stage is also discussed in the block of folding bus, to improve the bandwidth limitation and voltage gain by parasitic capacitances. The chip has been fabricated with $0.13{\mu}m$ 1P6M CMOS technology, the effective chip area is $1.5mm^2$. The measured results of INL and DNL are within 2.95LSB and l.24LSB at 10b resolution, respectively. The SNDR is 54.8dB and SFDR is 63.4dBc when the input frequency is 9.27MHz at sampling frequency of 500MHz. The ADC consumes 150mW($300{\mu}W/MS/s$) including peripheral circuits at 500MS/s and 1.2V(1.5V) power supply.