• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.6
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• pp.541-545
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• 2007

The critical current degradation behaviors of multifilamentary Bi-2223 superconducting tapes under pressurized liquid nitrogen were investigated using a r-shaped sample holder which gives a series of bending strains to tape. Three kinds of externally-reinforced Bi-2223 tapes with different hermeticity were used as samples. The tape with the thicker reinforcement layer had a better bending strain tolerance of $I_c$, but when the bending strain was calculated at the outermost filament, the $I_c$ degradation behavior became identical. For all samples, $I_{c0}$ decreased with the increase of applied pressure, but the $I_c$ degradation behavior with bending strain at each pressure level was similar. Furthermore, after depressurization from 1 MPa to atmospheric pressure, $I_c$ was completely recovered to its initial values. When the samples were warmed up to room temperature after pressurization tests, the ballooning damage occurred at lower bending strain regions. The region where ballooning was observed was identical to the one where the significant $I_c$ degradation occurred.

• Research in Mathematical Education
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• v.14 no.1
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• pp.19-31
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• 2010

Introduced in this paper is one of the most remarkable Ottoman institutions, the Ottoman Palace School-Enderun, with a focus on the life story of Matrak$\c{c}{\i}$ Nasuh, one of its most noted graduates and teachers. Matrak$\c{c}{\i}$ Nasuh's life and work as a prominent mathematician and a teacher of mathematics are investigated as a case study. It shows how young boys and girls were selected because of their academic potential, brought to Istanbul, and educated in Enderun to serve the Empire. This research articulates the mathematics education on the first institutionalized gifted education system of the world and discusses its implications for today.

• Herbal Formula Science
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• v.12 no.1
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• pp.209-223
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• 2004

Objective: This study was conducted to investigate the effects of Coptidis Rhizoma on the plasma IL-6 and $TNF-{\alpha}$ level in mice by intracerebroventricular(I.C.V.) injection of Lipopolysaccharide (LPS). Method: 6 mice were assigned to each of the Normal group, the Control group, and the individual Experimental groups. In the Normal group only saline was administered intragastrically, and in the Control group LPS was injected intracerebroventricularly 1 hr after intragastric administration of saline. In the Experimental groups Coptidis Rhizoma(0.5g/kg, 1.0g/kg, 3.0g/kg) was administered intragastrically to mice 1 hr prior to LPS (100ng/mouse) I.C.V. Injection. To measure the plasma IL-6 and $TNF-{\alpha}$ level of mice, their blood samples were collected from retro-orbital venous plexus, immediately centrifuged at $4^{\circ}C$, and plasma was removed and stored frozen at $-83^{\circ}C$ for later determination of plasma IL-6 and $TNF-{\alpha}$. Result: 1. LPS I.C.V. Injection increased plasma IL-6 level significantly in a dose-dependent manner compared with Normal group. (P<0.01) The plasma IL-6 concentration reached a significant maximal level about 1 hr after LPS(100ng/mouse) I.C.V. Injection.(P<0.001) 2. Both the 0.5g/kg(Sample A) and 1.0g/kg(Sample B) groups to which Coptidis Rhizoma was administered intragastrically 1 hr prior to LPS(100ng/mouse) I.C.V. Injection showed insignificant lower plama IL-6 level in 1 hr than Control group(P>0.05), and 3.0g/kg group(Sample C) conversely showed higher plama IL-6 level than Control group. 3. LPS I.C.V. Injection increased plasma $TNF-{\alpha}$ level significantly in a dose-dependent manner compared with Normal group.(P<0.05) The plasma $TNF-{\alpha}$ concentration reached a significant maximal level about 1 hr after LPS(100ng/mouse) I.C.V. Injection.(P<0.001) 4. All Sample groups(0.5g/kg, 1.0g/kg, and 3.0g/kg) to which Coptidis Rhizoma was administered intragastrically with each constituent-dose 1 hr prior to LPS(100ng/mouse) I.C.V. Injection showed significant lower $TNF-{\alpha}$ plama level in 1 hr than Control group.(P<0.001) These data revealed that Coptidis Rhizoma might have anti inflammatory effect by reducing the plasma $TNF-{\alpha}$ level in a dose dependent manner in mice LPS I.C.V. Injection.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.1
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• pp.64-69
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• 2019

Methylammonium lead triiodide ($MAPbI_3$)-based perovskite solar cells potentially have potential advantages such as high efficiency and low-cost manufacturing procedures. However, $MAPbI_3$ is structurally unstable and has low phase-change temperatures ($30^{\circ}C$ and $130^{\circ}C$); it is necessary to solve these problems. We investigated the crystal structure and phase separation using real-time temperature-change X-ray diffraction, transmission electron microscopy, and electron energy loss spectroscopy. $MAPbI_3$ has a tetragonal structure, and at about $35^{\circ}C$ the c-axis contracts, transforming $MAPbI_3$ into the related cubic crystal structure. In addition, at $130^{\circ}C$, phase separation occurs in which $CH_3NH_2$ and HI at the center of the unit cell of the perovskite structure are extracted by gas, leavingand only $PbI_2$ of the three-component structure, is produced as the final solid product.

• Proceedings of the Materials Research Society of Korea Conference
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• 1994.05a
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• pp.124-124
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• 1994

• Korean Journal of Optics and Photonics
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• v.4 no.1
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• pp.1-8
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• 1993

A design of four-mirror optical system with reduction magnification 5X for deep UV ($\lambda$=248 nm of KrF excimer laser) submicron lithography is presented. Initially by using the paraxial quantities, the domain of solution for $t=d_1+d_2+d_3$<0 (d;: distance between the mirror $c_i$ and $c_{i+1}$ is found for the system which is free from the four off-axial Seidel first order aberrations that are coma, astigmatism, field curvature, and distortion. The solution with $d_5$=2.95 (normalized with respect to $c_i$= -1) is choosen and the aspherization is carried out to the spherical mirror surfaces ($c_3$ and $c_4$ in order to reduce the axial and residual off-axial higher order aberrations. The numerical aperture of the final system is as large as 0.4, which gives Rayleigh resolution of 0.38 $\mu\textrm{m}$.

• Journal of fish pathology
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• v.20 no.2
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• pp.189-200
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• 2007

To investigate the innate immune response involved in early stage of anti-viral defence, carps were injected with UV-inactivated spring viraemia of carp virus (SVCV), poly inosinic:cytidylic acid (Poly I:C) and concanavalin A (Con A), respectively and examined lysozyme activity, serum complement activity and chemiluminescent (CL) response of leucocytes isolated from head kidney at 3 days post-injection. There was no significant difference in plasma lysozyme activities among all experimental groups. However, lysozyme activities of head kidney in the groups injected with antiviral activity inducers were significantly higher than those of the control injected with physiological saline. Bactericidal activities of serum of the groups injected with antiviral activity inducers were not significantly different from control group. However, the CL responses were significantly higher at lower dose of Poly I:C and Con A, whilst dose-dependent increase was shown in UV-inactivated SVCV-injected group. In the challenge test with 1×104 TCID50/fish of SVCV at 4 days post-injection, UV-inactivated SVCV- and Poly I:C-injected groups showed higher relative percent survival (RPS) than Con A-injected group. Furthermore, strong protection was observed in the group injected higher dose of Poly I:C although showed lower activities in lysozyme and CL response. These results suggested that Poly I:C might stimulate other factors belonging to non-specific immune system have induced protective immunity against the SVCV challenged.

• Convergence Security Journal
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• v.20 no.4
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• pp.27-34
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• 2020

Recently, the fourth industrial revolution technology has not only changed everyday life greatly through technological development, but has also become a major keyword in the establishment of defense policy. In particular, Internet of Things, cloud, big data, mobile and cybersecurity technologies, called ICBMS, were selected as core leading technologies in defense information policy along with artificial intelligence. Amid the growing importance of the fourth industrial revolution technology, research is being carried out to develop the C4I system, which is currently operated separately by the Joint Chiefs of Staff and each military, including the KJCCS, ATCIS, KNCCS and AFCCS, into an integrated system in preparation for future warfare. This is to solve the problem of reduced interoperability for joint operations, such as information exchange, by operating the C4I system for each domain. In addition, systems such as the establishment of an integrated C4I system and the U.S. military's Risk Management Framework (RMF) are essential for efficient control and safe operation of weapons systems as they are being developed into super-connected and super-intelligent systems. Therefore, in this paper, the intelligent cyber threat detection, management of users' access to information, and intelligent management and visualization of cyber threat are presented in the future C4I system based on big data/cloud.

• The Korean Nurse
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• v.9 no.6 s.50
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• pp.24-26
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• 1970

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.81-86
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• 2005

One of the endoglucanases, F-I-III, was purified from the culture filtrate of T. sp. C-4 through procedures including chromatography on Sephacryl S-200, DEAE-Sepharose A-50, and Chromatofocusing on Mono-P (FPLC). The molecular weight of the enzyme was determined to be about 56,000 Da by SDS-PAGE, and pI of 4.9 by analytical isoelectric focusing. F-I-III showed the highest enzyme activity at $55^{\circ}C$, and the pH optimum of the enzyme was 5.0. There was no loss of activity when the enzyme was incubated at $50^{\circ}C$ for 24 hours. The specific activity of the enzyme F-I-III toward the CMC was 315.4 U/mg. The Km value for $PNPG_2$ of F-I-III was 2.69 mM. N-terminal sequence of F-I-III was analyzed to be QPGTSTPEVHPKKLTTYK. It showed $95\%$ of homology to that of EGI from T. reesei. The presence of some metal ions (1 mM) had only a little effect on CMCase activity. The treatment of the reducing agents resulted in the increase of endoglucanase activity.