• Progress in Superconductivity
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• v.1 no.1
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• pp.31-35
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• 1999

We have fabricated and tested a simple circuit of the rapid single-flux-quantum(RSFQ) four-stage shift register using a single layer high-$T_c$ superconducting (HTS) $YBa_2Cu_3O_{7-x}$ (YBCO) thin film structure with 9 step-edge Josephson junctions. The circuit includes two read superconducting quantum interference devices(SQUID) and four stages. To establish a robust HTS RSFQ device fabrication process, we have focussed on the reproducible process of sharp and straight step-edge formation as well as the ratio of film thickness to step height, t/h. The spread of step-edge junction parameters was measured from each 13 junctions with t/h=1/3, 1/2, and 2/3 at various temperatures. We have demonstrated the simplified operation of the shift register at 65 K.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.3
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• pp.1-5
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• 1985

CulnSe2 single crystals were grown by the Bridgman method. The n.CulnSe2 single cry seals with a carrier concentration of 2.6$\times$1016/㎤ were obtained by a thermal treatment of the grown CulnSe2 single crystals in selenium atmosphere. The solar cell of n.CulnSe2-3M KOH+3M Na2 S+4M S junction was prepared by using n.Culnsel single crystal as a photoanode, 3M KOH+SM Nat S+4M S as Polysulfide solutions. The FF of the solar cell was 0.44 under 100 mW/cml illumination condition, and the conversion efficiency was 5.67%.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.654-654
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• 2013

One of the most important yet unresolved problems in molecular electronics is the controversy over the number and nature of multiple conductance peaks in single-molecule junctions. Currently, there are three competing explanations of this observation: (1) manifestation of different molecule-electrode contact geometries, (2) formation of gauche defects within the molecular core, (3) involvement of different electrode surface orientations [1]. However, the exact origin of multiple conductance peaks is not yet fully understood, which indicates our incomplete understanding of the scientifically as well as techno-logically important organic-metal contacts. To theoretically resolve this problem, we previously applied a multiscale computational approach that combines force fields molecular dynamics (FF MD), density functional theory (DFT), and matrix Green's function (MGF) calculations [2] to a thermally fluctuating haxanedithiol (C6DT) molecule stretched between flat Au(111) electrodes, but could observe only a single conductance peak [3]. In this presentation, using DFT geometry optimizations and MGF calculations, we consider molecular junctions with more realistic molecule-metal contact conformations and Au(111) electrode surface directions. We also conduct DFT-based molecular dynamics for the highly stretched junction models to confirm our conclusion. We conclude that the S-Au coordination number should be the more dominant factor than the electrode surface orientation.

• Journal of Life Science
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• v.17 no.11
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• pp.1517-1522
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• 2007

Gap junction channels formed by two adjacent cells allow the passage of small molecules up to ${\sim}\;1\;kDa$ between them. Hemichannel (connexon or half of gap junction) also behaves as a membrane channel like sodium or potassium channels in a single cell membrane. Among 26 types of connexin (Cx), $Cx32^*43E1$ (a chimera in which the first extracellular loop of Cx32 has been replaced with that of Cx43), Cx38, Cx46, and Cx50 form functional hemichannels as well as gap junction channels. Although it is known that Xenopus oocytes express endogenous connexin 38 (Cx38), its biophysical characteristics at single channel level are poorly understood. In this study, we performed single channel recordings from single Xenopus oocytes to acquire the biophysical properties of Cx38 including voltage-dependent gating and permeation (conductance and selectivity). The voltage-dependent fast and slow gatings of Cx38 hemichannel are distinct. Fast gating events occur at positive potentials and their open probabilities are low. In contrast, slow gatings dominate at negative potentials with high open probabilites. Based on hi-ionic experiments, Cx38 hemichannel is anion-selective. It will be interesting to test whether charged amino acid residues in the amino terminus of Cx38 are responsible for voltage gatings and permeation.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1993.10a
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• pp.63-67
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• 1993

In single-layer latticed domes with two-way grid, if we use the cross-membered junction's method for the advantage in fabrication and construction, the eccentricity is occurred in the nodal point of crossing members. This paper is aimed at investigating the buckling characteristics for the effect of eccentricity. Analysis method is based on FEM dealing with the geometically nonlinear deflection problems. As a result of the study, in the case of having eccentricity, the values of buckling strength are about 0.7 times than or not but the characteristics of buckling and deflection except buckling strength have a similar tendency each other.

• Progress in Superconductivity and Cryogenics
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• v.4 no.1
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• pp.17-20
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• 2002

A complex single flux quantum(SFQ) circuit could be made up of various elementary cells such as JTL(Josephson transmission line), Splitter, XOR, DC/SFQ, SFQ/DC, T flip-flop, ‥‥, etc. In this work, we have designed and simulated a SFQ circuit, which consists of DC/SFQ, JTL and SFQ/DC, based on Nb/AlO$_{x}$Nb Josephson junction technology From the simulation, we could obtain the margins for various circuit parameters. And also we have successfully operated the circuit, which was fabricated with the same design, up to the input signal frequency of about 20 GHz.z.

• Progress in Superconductivity and Cryogenics
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• v.4 no.1
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• pp.35-39
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• 2002

We have simulated and laid out a Single Flux Quantum(SFQ) AND gate for Arithmetic Logic Unit by using XIC, WRspice and Lmeter. SFQ AND gate circuit is a combination of two D Flip-Flop. D Flip-Flop and dc SQUID are the similar shape form the fact that it has the loop inductor and two Josephson junction We obtained perating margins and accomplished layout of the AND gate. We got the margin of $\pm$38%. over. After layout, we drew mask for fabrication of SFQ AND sate. This mask was included AND gate, dcsfq, sfqdc, rs flip-flop and jtl.

• Journal of information and communication convergence engineering
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• v.4 no.2
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• pp.84-87
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• 2006

Lateral distributions of locally injected electrons and holes in an oxide-nitride-oxide (ONO) dielectric stack of two different silicon-oxide-nitride-oxide-silicon (SONOS) memory cells are evaluated by single-junction charge pumping technique. Spatial distribution of electrons injected by channel hot electron (CHE) for programming is limited to length of the ONO region in a locally ONO stacked cell, while is spread widely along with channel in a fully ONO stacked cell. Hot-holes generated by band-to-band tunneling for erasing are trapped into the oxide as well as the ONO stack in the locally ONO stacked cell.

• International Journal of Contents
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• v.11 no.3
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• pp.7-13
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• 2015

One of the biggest problems of skeletonization is the occurrence of distortions at the junction point of the final binary image. At the junction area, a single point usually becomes a small stroke, and the corresponding trajectory task, as well as the OCR, consequently becomes more complicated. We therefore propose an adaptive post-processing method that uses an adaptive threshold technique to correct the distortions. Our proposed method transforms the distorted segments into a single point so that they are as similar to the original image as possible, and this improves the static handwriting images after the skeletonization process. Further, we attained promising results regarding the usage of the enhanced skeletonized images in other applications, thereby proving the expediency and efficiency of the proposed method.

• Progress in Superconductivity
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• v.3 no.1
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• pp.87-90
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• 2001

We designed a high temperature superconducting rapid single flux quantum(RSFQ) T flip-flop(TFF) circuit using Xic and WRspice. According to the optimized circuit parameters, we fabricated the TFF circuit with $Y_1$$Ba_2$Cu$_3$$O_{7-x}$(YBCO) interface-controlled Josephson junctions. The whole circuit was comprised of five epitaxial layers including YBCO ground plane. The interface-controlled Josephson junction was fabricated with natural junction barrier that was formed by interface-treatment process. In addition, we report second design for a new flip-flop without ground palne.e.