According to ISO 4037, the thickness of the inherent filtration for the radiation qualities L-40 to L- 240, N-40 to N-400, W-60 to W-300 and H-80 to H-400 shall be equivalent to 4 mm Al for matched reference radiation fields or adjusted as far as possible to 4 mm Al for characterized reference radiation fields. And for matched reference fields, the tube window must be made of beryllium and its thickness should not exceed 10 mm. In the case of characterized reference fields, the thickness of the beryllium window should not exceed 10 mm, but it is acceptable to use an aluminum window with a maximum thickness of 1.5 mm. 320 KV X-ray tube installed at KHNP-CRI has been designed to equipped with a 3 mm Be for tube window and an additional 4 mm Al to obtain a total inherent filtration equivalent to that of 4 mm Al. In the previous study, the inherent filtration of 320 kV X-ray tube at KHNP-CRI has been verified by MCNP simulation. However, the ISO standards suggest a method for determining the thickness of the inherent filtration by half-value layer (HVL) measurement and spectrometry. In this regard, the inherent filtration was reassessed using HVL measurement. To determine the inherent filtration, 1st HVL of the beam generated by the tube at a tube potential 60 kV was measured. The measurements were conducted with a calibrated spherical ionization chamber (model A3, Exradine) placed at a distance of 1 m from the target, at the center of the radiation field size. The X-ray tube current was set to 2 mA. The thickness of aluminum absorbers was gradually adjusted in subsequent measurements until approached the 1st HVL. 1st HVL were estimated using the linear regression equation computed with the current values for the thickness of the absorbers. As a results, the thickness of the 1st HVL was estimated as 2.845 mm Al. According to the correlation between the inherent filtration and 1st HVL suggested in ISO standard, the value of the inherent filtration was deduced as 4.25 mm Al that is rounded to the nearest 0.05 mm by interpolation. Further studies on the effects of the inherent filtration thickness determined in this study will be conducted.

To obtain the gamma-ray energy spectrum of artificial radionuclides which is difficult to obtain practically, virtual gamma-ray energy spectrum simulator program was developed. It can be applied for the predetermined measurement condition for which the database was developed through computational simulation and actual measurement of background radiation. For gamma spectrometry training for KHNP HPGe detectors using this program, the database for KNPG HPGe detectors was developed. First, the geometry of the detector in the simulation was adjusted to resemble the real structure by comparing the actually measured net counts rate at the main gamma peak with the value simulated by MCNP6. The Certified Reference material (CRM) of 137Cs and 60Co were used for verification. The comparison was made with respect to the situation where CRM was attached to the top and side of the detection part of the considered detector. The geometry structures of detectors were simulated by reflecting the design drawing of the products, and the simulation was performed for several thicknesses of the Ge/Li dead layer in consideration of the change in the thickness over time. As the results, the simulation geometry was tuned so that the results for 137Cs showed a difference within 10% for all detectors. At this time, in some detectors, the result for 60Co shows a 10% higher error, which is estimated to be due to the random summing. It was not considered in tuning the simulation geometry, but it was found that improvements were needed to reflect the coincidence summing when construction the virtual spectrum in the future. The determined simulation geometry was applied to generate theoretical gamma-ray energy spectra of representative artificial radionuclides. In order to create a virtual spectrum similar to the real one, the background spectrum was measured for each detector without a source, and the simulation results were calculated in the form of having the same energy channel as the background spectrum. The background spectrum and theoretical spectra of artificial radionuclides for each detector were databased so that virtual spectra could be generated under desired conditions. The virtual spectrum was generated by adding a background spectrum and a spectrum obtained by multiplying the spectrum of the desired nuclide by the concentration of the nuclide. The validity of generated virtual spectra was verified using the pre-developed gamma spectrometry program. As a results of gamma spectrometry of virtual spectra, the virtual spectra was verified by showing a difference within 20% from the radioactivity value input when generating the virtual spectra.

Purpose: Most of all studies regarding corporate social responsibility have been dealing with its direct performance. Many previous studies provided the evidence that corporate social responsibility activities directly affect firms‘ competitiveness or corporate reputation. However, there are no studies regarding the role of social capital between corporate social responsibility and firms‘ competitiveness. The present study aims to examine a mediating role of social capital between corporate social responsibility and corporate reputation. Research design, data and methodology: The structural equation model integrating corporate social responsibility, social capital, and corporate reputation was proposed with three hypotheses. Questionnaire including 15 question items for three concepts was designed. Data for testing hypotheses were collected from students and staff who had experienced the social responsibility activities of Korea Hydro & Nuclear Co. Ltd. SPSS and SmartPLS were used to analyze data. Results: All three hypotheses were supported at the significance level of 0.01. Corporate social responsibility have a significant influence on social capital as well as corporate reputation. Social capital plays a mediating role in the relationship between corporate social responsibility and corporate reputation. Conclusions: The present paper identified a missing link between corporate social responsibility and corporate reputation by validating an indirect effect of corporate social responsibility on corporate reputation through social capital. The present study contributes to finding the indirect link between corporate social responsibility and corporate reputation. Implications for academics and practitioners. The research model can be extended to analyze the relationship between corporate social responsibility and its performance. The present study sheds light on identification of a new role of social capital. Managers of firms have the opportunity to recognize the fact that investment recovery of corporate social responsibility results from social capital and corporate reputation in long-term rather than short-term. The results of this study offers an insight that managers can enhance customer loyalty. The process linking corporate social responsibility to corporate reputation through social capital implies that firms can realize spiritual marketing delivering authentic storytelling through corporate social responsibility. The present study has a limitation for generalizing of research results because the sampling came from a case of firm.