• The KSFM Journal of Fluid Machinery
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• v.18 no.3
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• pp.46-52
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• 2015

Pump-turbine system is widely used by the hydropower industry for stabilizing the electrical grid in the vast growing economy of most developed countries. This study only investigates the Fluid-structure Interaction (FSI) analysis of the pump-turbine system at various operating conditions. The FSI analysis can show how reliable each component of the system is by providing the engineer with a better understanding of high stress and deformation points, which could reduce the lifespan of the pump-turbine. Pump-turbine components are categorized in two parts, pressurized static parts and movable stressed parts. The fixed parts include the spiral casing, top and bottom cover, stay vane and draft tube. The movable parts include guide vanes and impeller blades. Fine hexahedral numerical grids were used for CFD calculation and fine tetrahedral grids were used for structural analysis with imported load solution mapping greater than 90 %. The maximum equivalent stress are much smaller than the material yield stress, and the maximum equivalent stress showed an increasing tendency with the varying of operating conditions from partial to excessive at both modes. In addition, the total deformation of all the operating conditions showed a small magnitude, which have quite small influence on the structural stability. It can be conjectured that this system can be safely implemented.

• The Korean Journal of Mycology
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• v.31 no.3
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• pp.181-186
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• 2003

The production of laccase by Fomitella fraxinea was studied. The addition of minerals were necessary far laccase production by Fomitella fraxinea. Jar fermentor and Air-sparging fermentor performed high productivity In laccase activity by F. fraxinea. Laccase activity reached 3,540 in 8 days (Jar fermentor) and 3,100 in 6 days (Air-sparging fermentor) respectively.

• Journal of Korean Academy of Nursing
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• v.53 no.1
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• pp.39-54
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• 2023

Purpose: This study aimed to investigate the nationwide intention to delegate clinical practice of medical specialists in accordance with the enactment of the scope of practice for advanced practice nurses (APNs). Methods: Data were collected from October to December 2021 using Google Surveys. In total, 147 medical specialists from 12 provinces responded to the survey. The survey questionnaire was categorized into four legislative draft duties, according to the scope of practice (a total of 41 tasks): Twenty-nine tasks on treatments, injects, etc., performed under the guidance of a physician and other activities necessary for medical treatment (treatment domain); two tasks on collaboration and coordination; six tasks on education, counseling, and quality improvement; four regarding other necessary tasks. Participants were asked whether they were willing to delegate the tasks to APN. Results: The intention to delegate tasks to APN was higher for non-invasive tasks such as blood sampling (97.3%) or simple dressing (96.6%). Invasive tasks such as endotracheal tube insertion (10.2%), sampling: bone marrow biopsy & aspiration (23.8%) showed low intention to delegate in the treatment domain. Participants who were older, male, and had more work careers with APN, showed a higher intention to delegate tasks. Conclusion: To prevent confusion in the clinical setting, a clear agreement on the scope of APN practice as APN delegated by physicians should be established. Based on this study, legal practices that APN can perform legally should be established.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.4
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• pp.263-273
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• 2016

The effect of recirculated exhaust gas on performance and exhaust emissions with FGR rate are investigated by using a natural circulation, pressurized draft and water tube boiler with FGR system operating at several boiler loads and over fire air damper openings. The purpose of this study is to apply the FGR system to a power plant boiler for reducing $NO_x$ emissions. To activate the combustion, the OFA with 0 to 20% is supplied into the flame. When the suction damper of two stage combustion system installed in the upper side of wind box is opened by handling the lever between $0^{\circ}$ and $90^{\circ}$, also, the combustion air supplied to burner is changed. It is found that the fuel consumption rate per evaporation rate did not show an obvious tendency to increase or decrease with rising the FGR rate, and $NO_x$ emissions at the same OFA damper opening are decreased, as FGR rates are elevated and boiler loads are dropped. While a trace amount of soot is emitted without regard to the operation conditions of boiler load, OFA damper opening and FGR rate, because soot emissions are eliminated by the electrostatic precipitator with a collecting efficiency of 86.7%.