• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.20 no.3
• /
• pp.273-279
• /
• 2007

Probabilistic Risk Assessment considering statistically random variables is performed for the preliminary design of an Arch Bridge. Component reliabilities of girders have been evaluated using the response surfaces of the design variables at the selected critical sections based on the maximum shear and negative moment locations. Response Surface Method (RSM) is successfully applied for reliability analyses lot this relatively small probability of failure of the complex structure, which is hard to be calculated by Monte-Carlo Simulations or by First Order Second Moment method that can not easily calculate the derivative terms in implicit limit state functions. For the analysis of system reliability, parallel resistance system composed of girders is modeled as a parallel series connection system. The upper and lower probabilities of failure for the structural system have been evaluated and compared with the suggested prediction method for the combination of failure modes. The suggested prediction method for the combination of failure modes reveals the unexpected combinations of element failures in significantly reduced time and efforts, compared with the previous permutation method or conventional system reliability analysis method.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.31 no.5A
• /
• pp.351-360
• /
• 2011

Jacket-type offshore structures are always exposed to severe environmental conditions such as salt, high speed of current, wave, and wind compared with other onshore structures. In spite of the importance of maintaining the structural integrity for offshore structure, there are few cases to apply structural health monitoring (SHM) system in practice. The impedance-based SHM is a kind of local SHM techniques and to date, numerous techniques and algorithms have been proposed for local SHM of real-scale structures. However, it still requires a significant challenge for practical applications to compensate unknown environmental effects and to extract only damage features from impedance signals. In this study, the impedance-based SHM was carried out on a 1/20-scaled model of an Uldolmok current power plant structure under changes in temperature and transverse loadings. Principal component analysis (PCA) was applied using conventional damage index to eliminate principal components sensitive to environmental change. It was found that the proposed PCA-base approach is an effective tool for long-term SHM under significant environmental changes.

• The Journal of Korean Medicine
• /
• v.45 no.2
• /
• pp.55-73
• /
• 2024

Objectives: In this study, we used network-based systems pharmacology analysis and molecular docking methods to predict the therapeutic mechanism of Scutellariae Radix on viral pneumonia. Methods: We screened active components of Scutellariae Radix and its' genes by TCMSP. Also, we extracted viral pneumonia related target genes through Gene Cards, CTD and DisGeNet. To construct Protein-protein Interaction, STRING database was used. For functional enrichment, using SRplot platform, genes were classified by 3 categories: cellular component (CC), molecular function (MF) and biological process (BP). Molecular docking was conducted by AutoDockTools (version 4.2.6). Results: 32 Network-based systematic pharmacology analysis identified 37 target genes associated with baicalein. Based on the network and gene ontology analysis of the active ingredient's target genes and disease target genes, we identified nine core genes (AKT1, BAX, BCL2, CASP3, HIF1A, PTGS2, RELA, TP53, VEGFA) and HSP90 as involved. Notably, HIF1A showed the highest relevance, overlapping with two or more utilized programs. Hypoxia-inducible factor 1-alpha (HIF-1α) has been implicated in the expression of inflammatory cytokines, the induction of hypoxia, and the triggering of cytokine storms. Baicalein, a major component of SR, binds to both HIF-1α and HSP90, suggesting that it may be a possible targeted treatment for viral pneumonia. Conclusions: Baicalein may bind to HIF-1α to control inflammation caused by viral infectious diseases and may also regulate hypoxic conditions to prevent impairment of lung function caused by an overactive immune system. These findings suggest further research into the molecular mechanisms involved in hypoxia and provide a scientific basis for improving the treatment of viral infectious diseases.

• Journal of KIISE:Computing Practices and Letters
• /
• v.9 no.2
• /
• pp.191-204
• /
• 2003

In the home gateway environment, several characteristics for the user authentication mechanism should be reflected separately from the existing distributed service environment. First, the platform of a home gateway is a component based system that its services are installed dynamically. Second, the convenience that user can use several services by authentication of once should be offered. Finally, the system resources of a home gateway are restricted. However, a user authentication mechanism that reflected these characteristics is not shown at the user admin service specification of the OSGi service platform.(OSGi is the representative standardization organization of hone gateway.) Also, there is no existing authentication protocol that satisfies these qualities at the same time. In this paper, we propose a new user authentication mechanism considering those characteristics for the home gateway environment. We also design and implement an independent authentication service bundle based on the OSGi service platform so that it can perform user authentication operations for each bundle service. We supplement and extend the Kerberos Protocol that can apply.

• Journal of the Korean Society of Safety
• /
• v.20 no.2 s.70
• /
• pp.162-168
• /
• 2005

The lower flash points for the n-propanol+n-decane flammable mixture were measured by the Tag open-cup apparatus(ASTM D 1310). The experimental results of mixture exhibited the lower flash point than those of pure component in the flash point versus composition curve. The experimental value of the minimum flash point is $27^{\circ}C$ at a mole fraction of n-propanol of 0.71, and the flash point of n-propanol was $28^{\circ}C$. The experimentally obtained data were compared with the values that had been calculated by use of the prediction model, which assumes an ideal solution, and the flash point prediction models based on the van Laar equation were used to estimate the activity coefficients. The predictive curve based on an ideal solution deviated from the experimental data for this system. The experimental results demonstrate a close agreement with the predicted curves, which used the van Laar equation. The average absolute deviation(A.A.D.) from using the van Lau equation is $0.83^{\circ}C$. The methodology proposed here in this paper can thus be applied to incorporate an inherently safer design for chemical processes, such as determining safe storage and handling conditions for flammable solutions.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.62 no.7
• /
• pp.905-912
• /
• 2013

Power system fault analysis is commonly based on well-known symmetrical component method, which describes power system elements by positive, negative and zero sequence impedance. In case of balanced fault, such as three phase short circuit, transmission line can be represented by positive sequence impedance only. The majority of fault in transmission lines, however, is unbalanced fault, such as line-to-ground faults, so that both positive and zero sequence impedance is required for fault analysis. When unbalanced fault occurs, zero sequence current flows through earth and skywires in overhead transmission systems and through cable sheaths and earth in cable transmission systems. Since zero sequence current distribution between cable sheath and earth is dependent on both sheath bondings and grounding configurations, care must be taken to calculate zero sequence impedance of underground cable transmission lines. In this paper, conventional and EMTP-based sequence impedance calculation methods were described and applied to 345kV cable transmission systems (4 circuit, OF 2000mm2). Calculation results showed that detailed circuit analysis is desirable to avoid possible errors of sequence impedance calculation resulted from various configuration of cable sheath bonding and grounding in underground cable transmission systems.

• Journal of Pharmacopuncture
• /
• v.13 no.3
• /
• pp.63-71
• /
• 2010

Objectives: Gallic acid (GA) is the major component of tannin which could be easily founded in various natural materials such as green tea, red tea, grape juice, and Corni Fructus. The purpose of this study is to investigate the effect of Gallic acid (GA) on production of interleukin (IL) in mouse macrophage Raw 264.7 cells stimulated by lipopolysaccharide (LPS). Methods: Productions of interleukins were measured by High-throughput Multiplex Bead based Assay with Bio-plex Suspension Array System based on $xMAP^{(R)}$ (multi-analyte profiling beads) technology. Firstly, cell culture supernatant was obtained after treatment with LPS and GA for 24 hour. Then, it was incubated with the antibody-conjugated beads for 30 minutes. And detection antibody was added and incubated for 30 minutes. And Strepavidin-conjugated Phycoerythrin (SAPE) was added. After incubation for 30 minutes, the level of SAPE fluorescence was analyzed on Bio-plex Suspension Array System and concentration of interleukin was determined. Results: The results of the experiment are as follows. 1. GA significantly inhibited the production of IL-3, IL-10, IL-12p40, and IL-17 in LPS-induced mouse macrophage RAW 264.7 cells at the concentration of 25, 50, 100, 200 uM (p<0.05). 2. GA significantly inhibited the production of IL-6 in LPS-induced mouse macrophage RAW 264.7 cells at the concentration of 50, 100, 200 uM (p<0.05). 3. GA diminished the production of some cytokine such as IL-4, IL-5, and IL-13 in LPS-induced mouse macrophage RAW 264.7 cells. 4. GA did not show the inhibitory effect on the production of IL-$1{\alpha}$ and IL-9 in LPS-induced mouse macrophage RAW 264.7 cells. Conclusions: These results suggest that GA has anti-inflammatory activity related with its inhibitory effects on the production of interleukins such as IL-3, IL-10, IL-12p40, IL-17, and IL-6 in LPS-induced macrophages.

• Journal of Conservation Science
• /
• v.35 no.4
• /
• pp.317-329
• /
• 2019

Slag was collected from the iron-producing furnace site in Saengsoegol, Baegun mountain, where iron was manufactured by a righteous army against Japan in the Gwangyang region; then, the iron-manufacturing technique of the early modern period was investigated through scientific analysis. In the microstructure analysis results of the selected samples, iron bloom was mainly observed together with magnetite and fayalite. In the component analysis results of the compounds, it was confirmed that the furnace was built by using gangue of alkali feldspar or plagioclase series, and the ironmaking work was performed at a high temperature of at least 1050℃, because mullite was identified together with cristobalite and hercynite. Based on the chemical composition, it was speculated that low-grade iron ores were used as raw materials, and it seemed that the yield was low, because the total Fe content of the smelting slag samples was 37.72-49.93%. It was difficult to confirm whether a slag former was used, and it seemed that materials easily obtained nearby were used when the furnace was built, without considering the corrosion resistance. It appeared that the ironmaking work was performed at the Gwangyang Saengsoegol iron-producing furnace based on the direct ironmaking method in an environment that could escape the vigilance of the Japanese Empire to produce weapons that would be used for the resistance against Japan. It seemed that there was neither an advanced ironware production system nor a mass production system, and small-scale works were performed in short periods of time.

• Journal of Korea Multimedia Society
• /
• v.3 no.5
• /
• pp.516-525
• /
• 2000

A lot of efforts have been made to develop a new technology for efficient distance education based on a powerful Internet service like World Wide Web. By developed distance education systems, we can study something we want at anytime and anywhere. However in spite of the excellent achievements we have made, something insufficient still is remained. Distance education methods only depending on static homepages or voices and simple drawings may be insufficient to support as much effects as in real class. So it is necessary to develop a new method for teaching students more feasibly and efficiently In this paper, we try to design and implement a lecture authoring system that offers effective distance education with voices, animations, camera images, drawings and etc.. We can expect the designed system can give more efficient education effects like a face-to-face lecture in real class. The enclosed function of intense compression enables to transmit the lectures more speedily. Besides it has caption processing function to serve additional informations to students with caption texts, messages and hyperlinks.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.24 no.3
• /
• pp.123-128
• /
• 2020

Analysis of the 2016 Gyeongju earthquake and the 2017 Pohang earthquake showed the characteristics of a typical high-frequency earthquake with many high-frequency components, short time strong motion duration, and large peak ground acceleration relative to the magnitude of the earthquake. Domestic nuclear power plants were designed and evaluated based on NRC's Regulatory Guide 1.60 design response spectrum, which had a great deal of energy in the low-frequency range. Therefore, nuclear power plants should carry out seismic verification and seismic performance evaluation of systems, structures, and components by reflecting the domestic characteristics of earthquakes. In this study, high-frequency amplification factors that can be used for seismic verification and seismic performance evaluation of nuclear power plant systems, structures, and equipment were analyzed. In order to analyze the high-frequency amplification factor, five sets of seismic time history were generated, which were matched with the uniform hazard response spectrum to reflect the characteristics of domestic earthquake motion. The nuclear power plant was subjected to seismic analysis for the construction of the Korean standard nuclear power plant, OPR1000, which is a reactor building, an auxiliary building assembly, a component cooling water heat exchanger building, and an essential service water building. Based on the results of the seismic analysis, a high-frequency amplification factor was derived upon the calculation of the floor response spectrum of the important locations of nuclear power plants. The high-frequency amplification factor can be effectively used for the seismic verification and seismic performance evaluation of electric equipment which are sensitive to high-frequency earthquakes.