Publications by authors named "Bokyeong Lee"

Infliximab (IFX) has transformed the management of inflammatory bowel diseases (IBD). While intravenous (IV) IFX has been effective, a subcutaneous (SC) formulation offers advantages in convenience and cost. However, there is lack of evidence regarding the transition from IV to SC-IFX, especially for patients with inadequate responses.

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Wave power marine concrete structures generate electrical energy using waves. They are exposed to a multi-deterioration environment because of air and hydrostatic pressure and chloride attack. In this study, the effect of air pressure repeatedly generated by water level change of wave power marine concrete structures on the chloride-ion diffusion of marine concrete was analyzed.

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This study investigated the physical properties of section-restoration mortar with calcium nitrite (Ca(NO)) and carbon dioxide (CO) nanobubble mixing water to develop materials and methods for the repair and reinforcement of cracks in reinforced concrete (RC) structures. As the calcium nitrite content increased, the generation rate and generated amount of nitrite-based hydration products also increased, owing to the rapid reaction between NO ions in calcium nitrite and CA(AlO). Further, the reaction with CS and CS was accelerated, thereby increasing the generation rates of Ca(OH) and C-S-H.

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Integrated gasification combined cycle (IGCC) is a highly efficient method for producing electricity but discharges a byproduct in the form of a glassy slag, similar to other electricity generation operations. Several technologies for recycling IGCC slag have been developed thus far, although the results obtained are not promising or universally applicable. We quantitatively characterized an IGCC slag by using various testing methods, including an automated scanning electron microscopy-energy dispersive spectrometry (SEM-EDS) system, to recognize its potential for recycling.

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There has recently been an increased use of anti-freezing agents that are primarily composed of salt- and alkali-free calcium nitrite (Ca(NO)) and calcium nitrate (Ca(NO)) to promote the hydration reaction of concrete in cold weather concreting. Nitrite-nitrate based accelerators accelerate the hydration of CA and CS in cement more quickly when their quantities are increased, thereby boosting the concrete's early strength and effectively preventing early frost damage. However, the connection between the hydrate formation behavior and the strength development characteristic over time has yet to be clearly identified.

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In this study, the shrinkage and durability of environmental load-reducing fiber-reinforced polymer cement mortar (FRPCM) were examined by using silicone oil. The results indicated that the shrinkage can be greatly reduced by adding silicone oil. However, when the silicone oil is added in excess, it affects the strength and durability.

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This study focused on the quick initial setting time and the expansion strain that occurs during the early aging of α-calcium sulfate hemihydrate (αHH) and examined the setting, compressive strength, and shrinkage strain of αHH-replaced cement mortar. The results show that the initial setting time significantly decreased with an increase in the αHH replacement ratio. Drastic occurrence of ettringite was observed early in the aging of cement mortar when αHH was substituted into the cement; however, the ettringite was not converted to monosulfate with increasing age and thus was not favorable for the development of the compressive strength.

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