• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.179-182
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• 2000

BWLL용 Ka-Band MMIC 저잡음 증폭기 칩을 InGaAs/GaAs 0.15um Gate 길이의 p-HEMT 공정을 이용하여 개발하였다. 칩 크기 2.5$\times$1.5$\textrm{mm}^2$의 2단으로 설계된 칩의 On-wafer 측정 결과, 24～27 GHz BWLL 주파수 대역에서 최소 19$\pm$0.2dB 이득과 최대 1.7dB의 잡음 지수와 최소 13dB의 반사손실의 특성을 얻었다.

• Nonlinear Functional Analysis and Applications
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• v.26 no.1
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• pp.177-195
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• 2021

In this paper, we introduce the modification of a generalized (Ψ, L)-weak contraction and we prove some coincidence point results for self-mappings G, T and S, and some fixed point results for some maps by using a (c)-comparison function and a comparison function in the sense of a b-metric space.

• Nonlinear Functional Analysis and Applications
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• v.27 no.3
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• pp.663-677
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• 2022

This present paper extends some fixed point theorems in rectangular b-metric spaces using subadditive altering distance and establishing the existence and uniqueness of fixed point for Kannan type mappings. Non-trivial examples are further provided to support the hypotheses of our results.

• The Pure and Applied Mathematics
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• v.31 no.2
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• pp.235-249
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• 2024

We obtain a structured class of frames in separable Hilbert spaces which are generalizations of Gabor frames in L²(ℝ) in their construction aspects. For this, the concept of Gabor type unitary systems in [13] is generalized by considering a system of invertible operators in place of unitary systems. Pseudo Gabor like frames and pseudo Gabor frames are introduced and the corresponding frame operators are characterized.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1414-1417
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• 1996

The purpose of this study Is to research and develop $V_{6}O_{13}$ composite cathode for lithium thin film battery. $V_{6}O_{13}$ represents a class of cathode active material used in Li rechargeable batteries. In this study, we investigated cyclic voltammetry and charge/discharge characteristics of $V_6O_{13}$/SPE/Li cells. Cyclic voltammogram of $V_{6}O_{13}$/SPE/Li cell at scan rate 1mV/sec showed reduction peaks of 2.25V and 2.4V and oxidation peaks of 2.4V and 2.2V. The discharge curve of $V_{6}O_{13}$/SPE/Li cell showed 4 potential plateaus. The discharge capacity was decreased in the beginning of charge/discharge cycling. After 8th cycling, the discharge capacity was stable. The discharge capacity of 1st cycle and 15th cycle was 290mAh/g and 147mAh/g at $25^{\circ}C$, respectively.

• Progress in Superconductivity
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• v.12 no.1
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• pp.51-56
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• 2010

$^{13}C$ NMR (nuclear magnetic resonance) measurements have been performed to investigate the local electronic structure of a superconducting graphite intercalation compound $CaC_6$ ($T_c$ = 11.4 K). A large number of single crystals were stacked and sealed in a quartz tube for naturally abundant $^{13}C$ NMR. The spectrum, Knight shift, linewidth, and spin-lattice relaxation time $T_1$ were measured in the normal state as a function of temperature down to 80 K at 8.0 T perpendicular to the c-axis. The $^{13}C$ NMR spectrum shows a single narrow peak with a very small Knight shift. The Knight shift and the linewidth of the $^{13}C$ NMR are temperature-independent around, respectively, +0.012% and 1.2 kHz. The spin-lattice relaxation rate, $1/T_1$, is proportional to temperature confirming a Korringa behavior as for non-magnetic metals. The Korringa product is measured to be $T_1T\;=\;210\;s{\cdot}K$. From this value, the Korringa ratio is deduced to be $\xi$ = 0.73, close to unity, which suggests that the independent-electron description works well for $CaC_6$, without complications arising from correlation and many-body effects.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.197-198
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• 1996

We have carried out $^{13}CO$ J = 1 $\to$ 0 line observations with spatial resolution of 2' toward 17 small globules selected from the catalogue of Clemens & Barvainis (1988) with a selection criterion of [b] $\ge$ 15 degrees using the Nagoya 4-m radio telescope. Overall characteristics and physical parameters are presented and discussed by examining the $^{13}CO$ integrated intensity map for each of the globules.

• Natural Product Sciences
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• v.6 no.2
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• pp.102-105
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• 2000

Chemical investigation of the hot hexane extract of the stem bark of Gordonia dassanayakei afforded a new oleanane triterpenoid, $11{\alpha},13{\beta}-dihydroxyolean-3,12-dione$ (1) and two other oleanane triterpenoids, $3{\beta}-acetoxy-11{\alpha},13{\beta}-dihydroxyolean-12-one\;(2)\;and\;3{\beta},11{\alpha}-diacetoxy-13{\beta}-hydroxyolean-12-one\;(3)\;and\;a\;hopane\;6{\alpha},22-diol$ (4), which are new to the plant.

• Food Science and Preservation
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• v.21 no.6
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• pp.851-858
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• 2014

Muscat Bailey A (MBA) wine was fermented using the indigenous Korean Saccahromyces cerevisiae strains S13 and D8, and the fermentation characteristics were compared with those of S. cerevisiae W-3, an industrial wine yeast. The strains S13 and D8 showed delayed alcohol fermentation compared with the W-3 strain, but the final alcohol contents of the S13 and D8 wines after fermentation were similar to those of the W-3 wine. The S13 wine showed significantly lower malic-acid content than the W-3 wine, but the D8 wine showed a similar level. Both the wines fermented using the S13 and D8 strains showed significantly lower acetaldehyde, methanol, and fusel oil contents, including n-propanol, iso-butyl alcohol, and iso-amyl alcohol, compared to the W-3 wine. Especially, the methanol content was 98.6 mg/L in the S13 wine and 112.0 mg/L in the D8 wine, which were much lower than 192.8 mg/L in the W-3 wine. The S13 wine obtained the highest score in terms of color among the three wines in the sensory evaluation, with lower Hunter's L, a, and b values compared to the W-3 wine.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.2
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• pp.481-485
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• 2003

Experimental studies were done to research the clinical effects of Juglandis Semen aqua-acupuncture and acupuncture(BL13, BL17, BL13ㆍ17 and free points) on the anti-allergic inflammation response. The following results have been obtained ; JSAA was increased in the lymphocyte proliferation in cultured murine thymocytes and splenocytes. The production of IL-1β was decreased in Juglandis Semen aqua-acupuncture and acupuncture(BL13, BL17 and BL13ㆍ17) group. The production of IL-4 was decreased in Juglandis Semen aqua-acupuncture and acupuncture(BL13, BL17 and BL13ㆍ17) group. The production of total IgG was decreased in Juglandis Semen aqua-acupuncture(BL13 and BL13ㆍ17) and acupuncture(BL13, BL17 and BL13ㆍ17) group. According to the above results, Semen aqua-acupuncture and acupuncture(BL13, BL17 and BL13ㆍ17) both enhances the specific immune response in T and B cells and depress the allergic inflammation reaction.