• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.273-276
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• 2002

• The Korean Journal of Ceramics
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• v.4 no.4
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• pp.336-339
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• 1998

Bioactive titanium metal can be prepared by simple 5M-NaOH treatment and subsuquent heat treatment at $600^{\circ}C$ to form an amorphous sodium titanate on its surface. In the present study, mechanism of apatite formation on the titanium metal was investigated by examining its surface compositional and structural changes in a simulated body fluid. The apatite formation on the metal was found to proceed in the sequence of 1)$Na^+$ ion release from the sodium titanate to form hydrated titania abundant in Ti-OH groups, 2) early and selective binding of calcium ions with the Ti-OH groups to form a calcium titanate, and 3) late binding of phosphate ions to make apatite nucleation and growth. This indicates that Ti-OH groups do not directly induce the apatite nucleation, but via formation of a calcium titanate.

• Molecules and Cells
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• v.45 no.12
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• pp.886-895
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• 2022

Malignant rhabdoid tumor (MRT) is a highly aggressive pediatric malignancy with no effective therapy. Therefore, it is necessary to identify a target for the development of novel molecule-targeting therapeutic agents. In this study, we report the importance of the runt-related transcription factor 1 (RUNX1) and RUNX1-Baculoviral IAP (inhibitor of apoptosis) Repeat-Containing 5 (BIRC5/survivin) axis in the proliferation of MRT cells, as it can be used as an ideal target for anti-tumor strategies. The mechanism of this reaction can be explained by the interaction of RUNX1 with the RUNX1-binding DNA sequence located in the survivin promoter and its positive regulation. Specific knockdown of RUNX1 led to decreased expression of survivin, which subsequently suppressed the proliferation of MRT cells in vitro and in vivo. We also found that our novel RUNX inhibitor, Chb-M, which switches off RUNX1 using alkylating agent-conjugated pyrrole-imidazole polyamides designed to specifically bind to consensus RUNX-binding sequences (5'-TGTGGT-3'), inhibited survivin expression in vivo. Taken together, we identified a novel interaction between RUNX1 and survivin in MRT. Therefore the negative regulation of RUNX1 activity may be a novel strategy for MRT treatment.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.181-184
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• 2006

Nano Infiltration Transient Eutectic Phase - Silicon Carbide (NITE-SiC) and $SiC_f/SiC$ composite have been fabricated by a Hot Pressing (HP) process, using SiC powder with an average size of about 30nm. Alumina ($Al_2O_3$) and Yttria ($Y_2O_3$) were used for additives materials. These mixed powders were sintered at the temperature a of $1300^{\circ}C$, $1650^{\circ}C$, $1800^{\circ}C$ and $1900^{\circ}C$ under an applied pressure of 20MPa. And unidirection and two dimension woven structures of $SiC_f/SiC$ composites were prepared starting from Tyranno SA fiber. Densification of microstructure gives an effect to density. Specially, Densification Mechanism basically is important from the sintering which use the HP. In this study, the densification of NITE-SiC and $SiC_f/SiC$ composite mechanism by a press displacement appears investigated. The mechanism on the densification of each sintering temperature was investigated. The each step is shows a with each other different mechanism quality.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.959-960
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• 2006

Li reacts with $N_2$ at room temperature. In order to activate Li, the mechanical milling of Li with stable metal oxide, namely, $Al_2O_3$ and MgO, using a high energy vibrating ball mill was performed. In the case of Li-MgO system, it reacts with $N_2$, but hardly reacts with $O_2$. The reaction with $N_2$ generally produces $Li_3N$, while for some vigorous reactions the $Mg_3N_2$ is produced as the major phases. In the case of $Li-Al_2O_3$ system, reactivities with both $N_2$ and $O_2$ are high. The difference is explained in terms of the reaction mechanism and the Li state.

• Earthquakes and Structures
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• v.5 no.3
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• pp.261-276
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• 2013

Oil, hysteretic and inertial mass dampers are representatives of passive dampers used for smart enhancement of seismic performance of building structures. Since oil dampers have a nonlinear relief mechanism and hysteretic dampers possess nonlinear restoring-force characteristics, several difficulties arise in the evaluation of buildings including such dampers. The purpose of this paper is to propose a practical method for simultaneous optimal use of such dampers. The optimum design problem is formulated so as to minimize the maximum interstory drift under design earthquakes in terms of a set of damper quantities subject to an equality constraint on the total cost of dampers. The proposed method to solve the optimum design problem is a successive procedure which consists of two steps. The first step is a sensitivity analysis by using nonlinear time-history response analyses, and the second step is a modification of the set of damper quantities based upon the sensitivity analysis. Numerical examples are conducted to demonstrate the effectiveness and validity of the proposed design method.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1995.10a
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• pp.1-4
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• 1995

Storm surges are defined as abnormal changes of sea surface elevation whose periods range from several hours to days. The generation mechanism is separated into two. One is sea water suction due to atmospheric depression and the other is wind-driven sea water circulation. The former is a forced long-wave motion which is accompanied by a typhoon. (omitted)

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.71-72
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• 1996

We show that the star formation activity of spiral galaxies has a great variety. The star formation variation in a time scale of $10^8$ yr and the mechanism responsible for the variation are discussed.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.343-344
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• 2006

Consumption of fossil fuel has been increasing steadily, and it has seriously affected environment. Due to this situation, UN establish ed UNFCC (United rations Framework Convention on Climate Change), and since Feb. 2005, Kyoto Protocol has come into effect for UNFCC obligation. In Korean power system, coal and oil thermal generation emitting large CO2 form about 46% of total generation. Moreover since electricity dem and has been increasing continuously, various alternatives should be designed to comply with Kyoto Protocol. In this paper, we analyze changes of each GENCO's generation pattern and resource planning under CO2 emission constraints. For this analysis, we incorporate CO2 emission constraints and the emission trading mechanism into the conventional OPF model.

• Proceedings of the Korean Society for Quality Management Conference
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• 2009.10a
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• pp.245-251
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• 2009

After the Kyoto Protocol has been ratitied in Feb. 16 2005, the developed countries which is involved in Annex-1 have tried to mitigate GHG to the reduction objective. To accomplish this objective, EU developed EU-ETS, CDM project, and so on. Korea has faced pressure to be a member of Annex-1, because Korea and Mexico are only non-Annex-1 countries in the OECD nations. This study is intended to examine unfolding transition on negotiations of Conference of Parties(COP), the Kyoto Mechanism referred as a cost-effective tool to meet a targeted level of greenhouse gas decrease, and trends in responses of developed countries to the Kyoto Protocol, and finally suggests legal and politic counterplans responding to the United Nations Framework Convention on Climate Change(hereafter, UNFCCC).