• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.4
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• pp.281-291
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• 2013

A hypothetical repository was assumed to be located at the KURT (KAERI Underground Research Tunnel) site, and the travel times of radionuclides released from three source positions were calculated. The groundwater flow around the KURT site was simulated and the groundwater pathways from the hypothetical source positions to the shallow groundwater were identified. Of the pathways, three pathways were selected because they had highly water-conductive features. The transport travel times of the radionuclides were calculated by a TDRW (Time-Domain Random Walk) method. Diffusion and sorption mechanisms in a host rock matrix as well as advection-dispersion mechanisms under the KURT field condition were considered. To reflect the radioactive decay, four decay chains with the radionuclides included in the high-level radioactive wastes were selected. From the simulation results, the half-life and distribution coefficient in the rock matrix, as well as multiple pathways, had an influence on the mass flux of the radionuclides. For enhancing the reliability of safety assessment, this reveals that identifying the history of the radionuclides contained in the high-level wastes and investigating the sorption processes between the radionuclides and the rock matrix in the field condition are preferentially necessary.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.307-312
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• 1997

원자력시설의 콘크리트 표면제염 및 절단을 효과적으로 수행하기 위해서는 먼저 방사성물질이 제염구역의 외부로 누출되지 않도록 작업구역을 비방사성 구역과 분리하고, 국부적으로 오염된 콘크리트 표면을 제염하는 기술, 해체 절단하는 기술 및 경제적인 방법으로 방사성물질의 확산을 최소화하는 분진제거 기술 등이 개발되어야 한다. 따라서 본 논문에서는 원자력시설의 콘크리트 표면제염 및 절단시 발생되는 콘크리트 분진처리 필터시스템을 개발하기 위하여, 중량 및 고밀도 콘크리트 내부로의 세슘 및 스트론튬 핵종의 침투깊이 실험을 수행하였으며, 다중 사이클론을 이용하여 DOP 에어로졸 및 콘크리트 표면절단 장비인 scabbier에 의해 발생한 중량 및 고밀도 콘크리트 분진의 특성을 분석하고 포집효율 성능시험을 수행하였다. 또한 사이클론 성능평가 프로그램을 작성하여 사이클론의 포집효율을 예상하였으며 이를 실험값과 비교하였다.

• Journal of Digital Convergence
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• v.15 no.8
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• pp.169-182
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• 2017

The purpose of this study is to empirically examine a behavior improvement of unethical information sharing through the ethics program in organization. An unethical behavior of information sharing on organization members is to be get to private interests through divulgence of company's confidential information. An unethical information-sharing of individual is the opportunist and selfish behavior for an expansion of social capital and shows a negative ripple effect in organization. When conducting the research methods, the analysis order performs the cluster, discriminant, t-test and multiple regressions. According to the study, There are differences the behavior of unethical information sharing between opportunist and non-opportunist. The opportunist member for unethical behavior improvement required the program operation both value and compliance oriented program. Non-opportunist member required only the value-oriented program. The upcoming research needs to explore both ethics program's frequency and action of a punished person.

• Journal of Chest Surgery
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• v.36 no.5
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• pp.321-328
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• 2003

Background: The St. Jude Medical prosthesis is one of the popularly used artificial prosthesis, therefore the National Medical Center reports the long-term clinical results of patients who underwent prosthetic valve replacement with St. Jude medical valve for 18 years. Material and Method: Between January, 1984 and June, 2002, a series of 163 consecutive patients who had Implanted St. Jude prosthesis at the National Medical Center were reviewed. Mean age was 42.9$\pm$15.1 years and male to female ratio was 69:94. The operative procedure comprised of 87 MVR, 30 AVR, 45 DVR, and 1 TVR. The reoperative procedure comprised of 21 MVR, 2 AVR, and 14 DVR. Follow-up rate was 96.9%, and cumulative follow-up was 823.8 patient-years. Result: Early mortality rate was 7.9% (13 patients), late mortality rate was 8.7% (13 patients) and late mortality due to valve related complication was 47% (7 patients). Actual survival rate at 10 and 18 years were 91.7$\pm$2.1% and 91.0$\pm$1.9%. Linearized Incidence was as follows: thromboembolism, 1.09%/ patient-year; anticoagulant related hemorrhage, 0.36%/patient-year; valve thrombosis, 0.24%/patient-year; paravalvular leakage, 0.12%/patient-year; and prosthetic bacterial endocarditis, 0.12%/patient-year linearized incidence of over all valve related complication was 1.94%/patient-year. Freedom from valve related complication at 10 and 18 years were 89.1$\pm$3.3% and 88.4$\pm$3.9%. Freedom from valve related death at 10 and 18 years were 95.1$\pm$1.2% and 95.1$\pm$1.0%. Valve related complication was related the age of patient, especially anticoagulant related hemorrhage was more common in patients over 60 years of age. Valve related complication, death were higher in DVR than AVR or MVR, and valve related death was higher in reoperation. There was no relationship between valve related complication or death and implant valve of size. Conclusion: The long-term clinical results of patients implanted with St. Jude Mechanical prosthesis was quite satisfactory with a low incidence of valve related complication and mortality.