• Korean Journal of Environmental Biology
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• v.23 no.2 s.58
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• pp.152-156
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• 2005

Ionizing radiation is a well- known therapy factor for human carcinoma cells. Genotoxic stress mediates cell cycle control, transcription and cellular signaling. In this work, we have used a microarray hybridization approach to characterize the cell type-specific transcriptional response of human carcinoma MCF-7 and HeLa cell line to $\gamma-radiation$, such as 4Gy 4hr. We found that exposure to $\gamma-ray$ alters by at least a $log_2$ factor of 1.0 the expression of known genes. Of the 27 genes affected by irradiation, 11 are down- regulated in MCF-7 cells and 2 genes induced by radiation,15 are repressed in HeLa cells. Many genes were involved in known damage- response pathways for cell cycling, transcription factor and cellular signaling response. However, in MCF-7 cells, we observed gene expression pattern in chromatin, apoptosis, stress, differentiation, cytokine, metabolism, ribosome and calcium. In HeLa cells, it showed clearly the expression changes in adhesion and migration, lysosome, brain, genome instability and translation. These insights reveal new therapy directions for studying the human carcinoma cell response to radiation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.824-828
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• 2007

In this paper Statistical Energy Analysis has been considered to predict middle, high frequency air borne interior noise. PIM method is used for verification. Damping loss factor and coupling loss factor have been derived from the response(SPL) of sub systems when the power is applied. The airborne SEA model of vehicle is modeled through AutoSea2. Insulation material's absorption coefficient and transmission loss are acquired from closed form solution and experiment.

• Journal of Korean Society of Steel Construction
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• v.9 no.2 s.31
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• pp.229-235
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• 1997

In order to check the influence of the randomness in yield strengths on the energy dissipation capacity of steel structures, behaviour factors applied for the "Response Spectrum Method" and their distributions are determined in this study with 7 steel framed models. Also 4 artificial accelerograms simulated with a given spectrum are applied to check the influence of the randomness in seismic action on the behviour factor. To execute numerous time-step calculations for the investigation a time-step analysis method is developed and applied after the reliability estimation to determine the action effects.

• Nuclear Engineering and Technology
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• v.34 no.6
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• pp.586-595
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• 2002

The Seismic probabilistic risk assessment (SPRA) or seismic margin assessment (SMA) have been used for the seismic safety evaluation of nuclear power plant structures and equipments. For the SPRA or SMA, the reference response spectrum should be defined. The site-specific median spectrum has been generally used for the seismic fragility analysis of structures and equipments in a Korean nuclear power plant Since the site-specific spectrum has been developed based on the peak ground motion parameter, the site-specific response spectrum does not represent the same probability of exceedance over the entire frequency range of interest. The uniform hazard spectrum is more appropriate to be used in seismic probabilistic risk assessment than the site- specific spectrum. A method for modifying the seismic fragility parameters that are calculated based on the site-specific median spectrum is described. This simple method was developed to incorporate the effects of the uniform hazard spectrum. The seismic fragility parameters of typical NPP components are modified using the uniform hazard spectrum. The modification factor is used to modify the original fragility parameters. An example uniform hazard spectrum is developed using the available seismic hazard data for the Korean nuclear power plant (NPP) site. This uniform hazard spectrum is used for the modification of fragility parameters.

• Journal of Radiation Protection and Research
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• v.28 no.4
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• pp.327-335
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• 2003

The commercially available neutron survey meter, the REM500, which uses a tissue equivalent proportional counter (TEPC) and the self-constructed TEPC were used to determine the microdosimetric quantities of several neutron calibration fields at Korea Atomic Energy Research Institute (KAERI). Microdosimetric spectra, absorbed dose, dose equivalent as well as quality factor were derived and compared with several neutron fields which were produced by using the shadow objects to make neutron scattered and being used as a kind of realistic neutron calibration fields at KAERI. The response of REM500 as a function of mean energy was evaluated with these neutron fields using the counts measured and the predetermined reference value. The response of the self-made TEPC and the REM500 was compared using one of the neutron calibration filelds of a $^{252}Cf$ source. The reference quantities of scattered neutron calibration fields were determined using a Bonner Sphere (BS). The value of frequency-mean lineal energy, dose-mean lineal energy and quality factor of two $^{252}Cf$ sources (unmoderated and $D_2O$ moderated) were determined to check the differences in the reference neutron fields between KAERI and Pacific Northwest National Laboratory (PNNL, USA) and the results were in good agreement within 1%. It means that there is no big difference in dosimetric quantifies of neutron calibration fields of two laboratories.

• Environmental Engineering Research
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• v.23 no.3
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• pp.309-315
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• 2018

Chlortetracycline (CTC) is one of the most important compounds in antibiotic production, and its distribution has been widely investigated due to health and ecological concerns. This study presents systematic approach to optimize the high-performance liquid chromatography-tandem mass spectrometry for analyzing CTC in a multiple reaction monitoring mode ($479{\rightarrow}462m/z$). One-factor-at-a-time (OFAT) test with response surface analysis (RSA) was used as optimization strategy. In OFAT tests, the fragmentor voltage, collision energy, and ratio of acetonitrile in the mobile phase were selected as major factors for RSA. The experimental conditions were determined using a composite in cube design (CCD) to maximize the peak area. As a result, the partial cubic model precisely predicted the peak area response with high statistical significance. In the model, the (solvent composition) and (collision $energy^2$) terms were statistically significant at the 0.1 ${\alpha}$-level, while the two-way interactions of the independent variables were negligible. By analyzing the model equation, the optimum conditions were derived as 114.9 V, 15.7 eV, and 70.9% for the fragmentor voltage, collision energy, and solvent composition, respectively. The RSA, coupled with the CCD, offered a comprehensive understanding of the peak area that responds to changes in experimental conditions.

• Journal of the Korean Wood Science and Technology
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• v.41 no.6
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• pp.497-506
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• 2013

The optimal condition for the torrefaction of eucalyptus (Eucalyptus globulus) was investigated by response surface methodology. The carbon content in the torrefied biomass increased with the severity factor (SF), while hydrogen and oxygen contents decreased. The calorific value of torrefied biomass ranged from 20.23 to 21.29 MJ/kg, depending on the torrefaction conditions. This implied that the energy contained in the torrefied biomass increased by 1.6 to 6.9%, when compared with that of the untreated biomass. The weight loss of biomass increased as the SF increased. The Code level of reaction temperature had the highest impact on the energy yield of torrefied biomass, while the effect of Code level of reaction time was considerably low. The highest energy yield was obtained at low SF.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.1
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• pp.1-9
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• 2013

In this study of Eccentric Braced Frames have identified the following target eccentricity on the length of the inelastic behavior of the reaction by calculating the correction factor by comparing it to the value suggested by the earthquake provided material for the rational design aims to There are. As a variable-length V-braced frame analysis model stations were set up. Eccentricity faults in the model according to the length stiffness ratio, the maximum amount of energy dissipation were analyzed base shear and multi-layered model of the reaction from the eccentricity correction factor calculated on the length of the building standards proposed by KBC 2009 in response eccentricity correction factor calculated from The length varies. does not have the same response modification factor was confirmed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.4
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• pp.404-413
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• 2000

Environmental chamber (EC) is an experimental facility used to analyze the characteristics of thermal response of testing objects by the artificial control of weather conditions. The EC in KIER can simulate the weather conditions by the control of temperature, humidity, and solar radiation. A two-storied testing building is located inside of EC. For the exact thermal response analysis of testing building, monthly or yearly scheduled operations are necessary. Although this long term operation gives the exact experimental data, it requires a high operational cost, long duration, and lots of manpower. Therefore it is necessary to perform the shortened experiments without sacrificing the validity of the obtained results. Since the characteristics of thermal response from the shortened experiments are different from the full time results, the analytical method to analyze the thermal response from the shortened experiments to estimate a full times results is developed in this study. The thermal response of testing building is performed using commercial software TRNSYS.

• International Journal of Air-Conditioning and Refrigeration
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• v.9 no.3
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• pp.18-26
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• 2001

Environmental chamber (EC) is an experimental facility used to analyze the characteristics of thermal response of testing objects by the artificial control of weather conditions. The EC in KIFR can simulate the weather conditions by the control of temperature, humidity, and solar radiation. A two-storied testing building is located inside EC. For the exact thermal response analysis of testing building, monthly or yearly scheduled operations are necessary. Although this long term operation gives the exact experimental data, it requires a high operational cost, long duration, and lots of manpower. Therefore it is necessary to perform the shortened experiments without sacrificing the validity of the obtained results. Since the characteristics of thermal response from the shortened experiments are different from the full time results, the analytical method to analyze the thermal response from the shortened experiments to estimate a full times results is developed in this study The thermal response of testing building is performed using commercial software TRNSYS.