• 한국초전도학회:학술대회논문집
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• v.9
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• pp.223-228
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• 1999

We have investigated the microwave properties of a high-T$_c$. superconducting Josephson junction by Shapiro step measurements. A Josephson junction was fabricated on the bicrystal MgO substrate using pulsed laser deposition method. We have measured Shapiro steps in the I-V characteristics under the irradiation of 1.36 cm wavelength up to 45 K and found inclined current steps above 50 K. In order to understand these results, we introduced an additional resistance connected in series to RSJ model. Using this modified RSJ model, we could explain the inclined current steps as a result of superposition of the junction and an additional resistance above certain temperatures. Also, we presented the received power of the Josephson junction above 50 K.

• 한국초전도학회:학술대회논문집
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• v.11
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• pp.45-45
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• 2001

• Progress in Superconductivity and Cryogenics
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• v.21 no.4
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• pp.13-18
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• 2019

Superconducting junctions of topological insulator (TI) are expected to host Majorana bound state, which is essential for developing topological quantum information devices. In this study, we fabricated Josephson junctions (JJs) made of Sb-doped Bi2Se3 TI nanoribbon and PbIn superconducting electrodes. In the normal state, the axial magnetoresistance data exhibit periodic oscillations, so-called Aharonov-Bohm oscillations, due to a metallic surface state of TI nanoribbon. At low temperature of 1.5 K, the TI JJ reveals the superconducting proximity effects, such as the critical current and multiple Andreev reflections. Under the application of microwave, integer Shapiro steps are observed with satisfying the ac Josephson relation. Our observations indicate that highly-transparent superconducting contacts are formed at the interface between TI nanoribbon and conventional superconductor, which would be useful to explore Majorana bound state in TI.

• The Journal of the Convergence on Culture Technology
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• v.8 no.1
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• pp.253-260
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• 2022

The purpose of this study was to identify the effects of human relations and communication education on nursing students. The participants were 82, 1 grad of students of U university in G city. The data were collected from September 3 to December 6, 2019, and analyzed using the SPSS/WIN 21.0 program with descriptive statistics, Shapiro-Wilk, Paired t-test. There were statistically significant differences in the subject's communication skill(t=-2.87, p=.005), communicative competence self-appraisal(t=-3.80, p=<.001) before and after human relations and communication education, but there was no statistically significant difference between interpersonal communication(t=-0.09, p=.931) and human relationship(t=-0.83, p=.409). Communication skills and skills are important nursing areas for nursing students as well as practical nurses, so continuous communication education is required. Therefore, it is necessary to develop a step-by-step program for improving communication skills of nursing students, apply continuous and repetitive education in connection from the lower grades to the upper grades, and follow-up research to verify the effect.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.415-423
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• 1996

Thin film technologies for fabricating SQUIDs involve etching and deposition procedures with the proper substrate materials and $YBa_2Cu_3O_{7-d}$ (YBCO) as the high $T_c$ superconductor. YBCO were prepared on various substrates of MgO, $SrTiO_3$, and $LaAlO_3$ by using off-axis magnetron sputtering methods and annealing in-situ. The parameters of film fabrication processes had been optimized to yield good quality films in terms of the critical temperature $T_c$ and the critical current density $J_c$. The optimized processes yielded $T_C$>90K along with $J_c$>$10_6A$$extrm{cm}^2$ at 77K and>$2\times10_7A/Cm^2$ at 5K. We fabricated step-edge type dc-SQUIDs and directly coupled magnetometers, producing step edges on MgO(100) substrates by etching with Ar-ion beam, depositing YBCO material on them, then patterning them by using ion-milling technique. Circuitizing washer-shape SQUIDs to possess a pair of step-edge junctions of 2-5$\mu$ line width with a high angle>$50^{\circ}C$ , we examined their I-V characteristics thoroughly and Shapiro steps clearly as we irradiate microwaves of 8-20 GHz frequency.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.2
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• pp.101-108
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• 2020

PURPOSE: The purpose of this study was to investigate the effect of treadmill walking training using the metronome on the gait pattern. METHODS: A total of 33 healthy persons were studied consisting of 17 female and 16 male in the 20-30 age group. A gait analysis program was installed on a treadmill with a built - in gait analysis sensor and laptop. After 9 minutes of treadmill walking, gait analysis was performed for 1 minute. The mean values of the differences in the step length, angle of COP, separation line standard deviation and step force of the lower legs affecting walking symmetry were calculated for treadmill walking and treadmill walking using the metronome. The Shapiro-Wilk test was used to test the normality of the collected data and a paired t-test was performed to analyze the difference in walking before and after using the metronome. RESULTS: As a result of the analysis, the mean of difference between the measured values of the bilateral lower extremity for step length, angle of COP, separation line standard deviation and step force were statistically significant before and after treadmill walking using the metronome. CONCLUSION: Therefore, the treadmill walking training using the metronome is effective in decreasing the difference in the foot width, gait angle, gait distribution, and foot pressure. Because of this, the treadmill walking training using the metronome has a significant effect on walking symmetry among the elements for correct walking, which is a means for enabling efficient and continuous walking.