• Journal of Korean Society of Archives and Records Management
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• v.1 no.2
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• pp.121-158
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• 2001

Development of R&D Knowledge Management System for Science & Technology Research Institutes, which was initiated early 2001, was introduced. The project, funded by the Ministry of Science and Technology, is being carried out by several R&D institutes in cooperation With implementers. The purposes of the project are: sharing knowledge about on-going research progresses and existing research results, facilitating cooperative efforts among research staff, teams, and institutes, and improving the efficiency of research project administration. The system consists of 4 components that are highly intertwined: Knowledge Portal, Knowledge Repository, Project Administration System and Groupware. This 3-year project will benefit R&D researchers, and R&D project carrying-out institutes and government project administration organization by facilitating research and development activities, and improving management efficiency, respectively.

• Polymer(Korea)
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• v.34 no.3
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• pp.220-225
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• 2010

The optical properties and dimensional stability of polyethersulfone(PES) retardation film have been studied as function of chain orientation and the temperature applied to PES retardation film. It was confirmed that the appropriate retardation values of $R_e$ and $R_{th}$ for the retardation film application were able to obtain by the chain orientation and these values could be controlled by the chain relaxation through the thermal annealing process. It was found that unstable $R_e$ and $R_{th}$ values were shown by the repeated cooling and heating applied to the retardation films but this could be stabilized by means of the annealing process after stretching of PES film. The dimensional shrinkage due to the chain orientation was found as temperature increase and the intrinsic thermal expansion of PES appeared after shrinking. The shrinkage of PES films affected by the chain orientation and thermal annealing dramatically but the effect on the coefficient of thermal expansion was found to be negligible.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3797-3803
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• 2009

Innovative capacities and performance are essential for the growth of the IT industry and the development of the Korean economy. Global R&D centers are important sources of innovation in the IT industry. In order to identify the structure of the innovation environment of global R&D centers in IT industry, we conducted a field survey of 50 global R&D centers and 50 global R&D policy experts in IT industry. According to the empirical results obtained using the Linear Structure Model, it is suggested that, first, with regard to a short-term IT global policy, the direction of the Korean government's policy should act as a trigger to connect the research domain and the market domain; second, the government policy should act as a facilitator to connect the development domain and the research domain in the mid-term period; and, finally, the government's R&D policy should serve as a disseminator to connect technological capability and the market space domain in the long-term perspective. For an effective way of internationalizing innovation, IT policy planners should regard global IT R&D centers as the important components of national innovation system and encourage the effective involvements by them in the process of IT industrial innovation.

• Journal of the Korean Society of Propulsion Engineers
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• v.25 no.3
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• pp.81-88
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• 2021

An airbreathing propulsion system of a subsonic cruise missile is mainly composed of a small gas turbine engine, air intake and vehicle's fuel tank. The propulsion system integration work started from engine acceptance test is finally closed by ground functional test of the missile's propulsion section, after some modifications of engine's sub-components, development of engine-related onboard systems, interface analyses, and tests. The whole process and stepwise technologies of this system integration work are described herein.

• YAKHAK HOEJI
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• v.43 no.2
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• pp.274-277
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• 1999

A study has been conducted to investigate the radioprotective effects of purslane extracts (P) when i.p. injected before irradiation (R). For studying the amino acid composition, three groups of ICR mice (7-week-old) were tested. The first group i.p. injected with purslane extract for 5 days were irradiated with 6 Gy of ${\gamma}$-radiation (P+R). The second group was irradiate with 6 Gy without any pretreatment (R). The third group was non-irradiated control (CT). Each group divided into two groups for the survival rate study, one injected with saline (S) and the other injected with purslane extract (P) for five days and then irradiated with 8 Gy. The amino acid composition of urine samples were analyzed with HPLC for 19 days after irradiation. A few kinds of amino acids such as lysine and methionine in urine from P+R group increased in comparison with those from CT or R group. The survival rate of P group maintained much higher than that of S group during experimental period. The results obtained may support that this plant has radioprotective substances by means of life-lengthening, not of urine amino acid components.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.1
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• pp.89-94
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• 2014

Stem bark extracts of Fraxinus rhynchophylla Hance were found to contain two major bioactive components, esculetin and esculin. Esculetin substantially inhibited melanogenesis in B16F10 melanoma cells, with an $IC_{50}$ value of $2.8{\mu}M$, and reduced melanin synthesis in Melan-A cells. Moreover, esculetin suppressed melanin biosynthesis by inhibiting mushroom tyrosinase activity, with an $IC_{50}$ value of $40{\mu}M$. Taken together, these results suggest that esculetin could serve as an effective skin-lightening agent that inhibits melanin production by regulating the activity of melanogenic enzymes.

• Journal of Ginseng Research
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• v.41 no.4
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• pp.496-502
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• 2017

Background: Ginsenosides are the major components of Panax ginseng Meyer, an herbal medicine used for the treatment of various diseases. Different ginsenosides contribute to the biological properties of ginseng, such as antimicrobial, anticancer, and immunomodulatory properties. In this study, we investigated the antiviral effects of 15 ginsenosides and compound K on gammaherpesvirus. Methods: The antiviral activity of ginsenosides was examined using the plaque-forming assay and by analyzing the expression of the lytic gene. Results: 20(R)-Ginsenoside Rh2 inhibited the replication and proliferation of murine gammaherpesvirus 68 (MHV-68), and its half-maximal inhibitory concentration ($IC_{50} $) against MHV-68 was estimated to be $2.77{\mu}M$. In addition, 20(R)-ginsenoside Rh2 inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced lytic replication of human gammaherpesvirus in the Kaposi's sarcoma-associated herpesvirus (KSHV)-positive cell line BC3. Conclusion: Our results indicate that 20(R)-ginsenoside Rh2 can inhibit the replication of mouse and human gammaherpesviruses, and thus, has the potential to treat gammaherpesvirus infection.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.102-103
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• 2007

In order to apply resistive superconducting fault current limiters into electric power systems, the urgent issues to be settled are as follows, such as initial installation price of SFCL, operation and maintenance cost due to ac loss of superconductor and the life of cryostat, and high voltage and high current problems. The ac loss and high cost of superconductor and cryostat system are main bottlenecks for real application. Furthermore in order to increase voltage and current ratings of SFCL, a lot of superconductor components should be connected in series and parallel which resulted in extreme high cost. Thus, in order to make practical SFCL, we designed novel hybrid SFCL which combines superconductor and conventional electric equipment including vacuum interrupter, power fuse and current limiting reactor. The main purpose of hybrid SFCL is to drastically reduce total usage of superconductor by adopting current commutation method by use of superconductor and high fast switch. Consequently, it was possible to get the satisfactory test results using this method, and further works for practical applications are in the process.

• Proceedings of the Microbiological Society of Korea Conference
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• 2008.05a
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• pp.23-25
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• 2008

Serum complement proteins comprise an important system that is responsible for several innate and adaptive immune defence mechanisms. There were three well described pathways known to lead to the generation of a C3 convertase, which catalyses the proteolysis of complement component C3, and leads to the formation of C3 opsonins (C3b, iC3b and C3d) that fix to bacteria. A pivotal step in the complement pathway is the assembly of a C3 convertase, which digests the C3 complement component to form microbial-binding C3 fragments recognized by leukocytes. The spleen clears microorganisms from the blood. Individuals lacking this organ are more susceptible to Streptococcus pneumoniae. Innate resistance to S. pneumoniae has previously been shown to involve complement components C3 and C4, however this resistance has only a partial requirement for mediators of these three pathways, such as immunoglobulin, factor B and mannose-binding lectin. Therefore it was likely that spleen and complement system provide resistance against blood-borne S. pneumoniae infection through unknown mechanism. To better understand the mechanisms involved, we studied Specific intracellular adhesion molecule-grabbing nonintegrin (SIGN)-R1. SIGN-R1, is a C-type lectin that is expressed at high levels by spleen marginal-zone macrophages and lymph-node macrophages. SIGN-R1 has previously been shown to be the main receptor for bacterial dextrans, as well as for the capsular pneumococcal polysaccharide (CPS) of S. pneumoniae. We examined the specific role of this receptor in the activation of complement. Using a monoclonal antibody that selectively downregulates SIGN-R1 expression in vivo, we show that in response to S. pneumoniae or CPS, SIGN-R1 mediates the immediate proteolysis of C3 and fixation of C3 opsonins to S. pneumoniae or to marginal-zone macrophages that had taken up CPS. These data indicate that SIGN-R1 is largely responsible for the rapid C3 convertase formation induced by S. pneumoniae in the spleen of mice. Also, we found that SIGN-R1 directly binds C1q and that C3 fixation by SIGN-R1 requires C1q and C4 but not factor B or immunoglobulin. Traditionally C3 convertase can be formed by the classical C1q- and immunoglobulin-dependent pathway, the alternative factor-B-dependent pathway and the soluble mannose-binding lectin pathway. Furthermore Conditional SIGN-R1 knockout mice developed deficits in C3 catabolism when given S. pneumoniae or its capsular polysaccharide intravenously. There were marked reductions in proteolysis of serum C3, deposition of C3 on organisms within SIGN-$R1^+$ spleen macrophages, and formation of C3 ligands. The transmembrane lectin SIGN-R1 therefore contributes to innate resistance by an unusual C3 activation pathway. We propose that in the SIGN-R1 mediated complement activation pathway, after binding to polysaccharide, SIGN-R1 captures C1q. SIGN-R1 can then, in association with several other complement proteins including C4, lead to the formation of a C3 convertase and fixation of C3. Therefore, this new pathway for C3 fixation by SIGN-R1, which is unusual as it is a classical C1q-dependent pathway that does not require immuno globulin, contributes to innate immune resistance to certain encapsulated microorganisms.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.634-639
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• 2000

This study was done to determine the changes in physicochemical components focused on the general compositions, pH, titratable acidity, organic acids, color and sugars during the microwave roasting of cocoa mass and to compare the changes with those during a conventional roasting. The cocoa mass was microwave-roasted at 110 to $150^{circ}C$ and for 10 to 40 min or conventionally roasted at $140^{circ}C$ for 30 min. General compositions of microwave-roasted cocoa mass were not different from those of raw cocoa mass or conventionally-roasted one. The pH changes did not affect the changes in titratable acidity or organic acids. Titratable acidity was different among the three samples. Microwave-roasted cocoa mass showed less sufficient effects on removing organic acids and less changes in color. Fructose, glucose and maltose decreased during a roasting but sucrose showed little changes.