• Membrane and Water Treatment
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• v.11 no.2
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• pp.167-172
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• 2020

The effectiveness of in situ sediment capping as a technique for heavy metal risk mitigation in Hyeongsan River estuary, South Korea was studied. Sites in the estuary were found previously to show moderate to high levels of contamination of mercury, methylmercury and other heavy metals. A 400 m x 50 m section of the river was selected for a thin layer capping demonstration, where the total area was divided into 4 sections capped with different combinations of capping materials (zeolite, AC/zeolite, AC/sand, zeolite/sand). Pore water concentrations in the different sites were studied using diffusive gradient in thin film (DGT) probes. All capping amendments showed reduction in the pore water concentration of the different heavy metals with top 5 cm showing %reduction greater than 90% for some heavy metals. The relative maxima for the different metals were found to be translated to lower depths with addition of the caps. For two-layered cap with AC, order of placement should be considered since AC can easily be displaced due to its relatively low density. Investigation of methylmercury (MeHg) in the site showed that MeHg and %MeHg in pore water corresponds well with maxima for sulfide, Fe and Mn suggesting mercury methylation as probably coupled with sulfate, Fe and Mn reduction in sediments. Our results showed that thin-layer capping of active sorbents AC and zeolite, in combination with passive sand caps, are potential remediation strategy for sediments contaminated with heavy metals.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.3
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• pp.518-536
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• 1997

The purpose of the present study was to analyze the pulpal tissue reactions to several capping materials. 8 adult Mongrel dogs and 4 different capping materials (G I : Calcium hydroxide, G II : Bonding resin, G III : Glass ionomer liner, G IV : Bioactive ceramic) we-reused in the study. The results can be summarized as follows : 1. The formation of hard tissue barrier was observed to begin after 2 weeks in all groups with various forms or positions. 2. According to the result of statistical analysis, G I and G IV showed significantly higher degree of inflammation than G II, G III in 1-week samples(p<.05). And in 2-week samples, G I showed higher degree of inflammation than G II, G IV with statistical significance(p<.05). Howere, these inflammatory reactions have gradually dimiished with time resulting in negligible difference between groups. 3. No bacterial penetration was observed in any group. 4. Hard tissue formation was evident in all groups after 2 weeks regardless of material type in this experiment. Conclusion can be drawn from the above-mentioned results that the perfect marginal sealing after pulp capping procedure is thought to be the most important factor in determining the propgnosis of direct pulp capping.

• Restorative Dentistry and Endodontics
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• v.46 no.3
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• pp.40.1-40.12
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• 2021

Objectives: The purpose of this study was to critically evaluate the quality, reliability and educational content of the information of vital pulp treatment videos available on YouTube. Materials and Methods: The keywords "pulpotomy" and "pulp capping" were searched on YouTube on 5th July 2020, until 60 English language videos of each search term with a duration shorter than 15 minutes were acquired. Video characteristics were recorded and Video Power Index (VPI) was calculated. Reliability and educational quality of videos were evaluated using the Modified DISCERN score, the Journal of American Medical Association (JAMA) benchmark criteria and Global Quality Scores (GQS). Videos were categorized by uploading source. Results: Regarding pulpotomy, 31.7% of the videos were uploaded by specialists and 68.3% were directed by non-specialists. In the case of pulp capping, the corresponding percentages were 45% and 55%, respectively. Videos uploaded by specialists had significantly higher modified DISCERN, JAMA and GQS scores compared to those uploaded by non-specialists. Endodontists tended to have the highest reliability and VPI scores. Conclusions: YouTube videos on vital pulp treatment contain low educational quality or incomplete information. Low popularity of dental pulp capping and pulpotomy videos may be attributed to the specialized nature of these procedures. As YouTube represents an important source for patient information about different health topics, reliable informative videos should be uploaded by specialized dental professionals.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.2
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• pp.45-52
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• 2008

Contaminant transport has been widely studied in rigid porous media, but there are some cases where a large volumetric stain occurs such as dewatering of dredged contaminated sediment, landfill liner, and in-situ capping. This paper presents a numerical investigation of contaminant transport coupled with large strain consolidation. Consolidation test was performed with contaminated sediments collected in Gary, Indiana, U.S. to obtain constitutive relationships, which are required for numerical simulations. Numerical results using CST2 show an excellent agreement with measured settlement and excess pore pressure. CST2 is then used to simulate contaminant transport during and after in-situ capping. Numerical simulations provide that transient advective flows caused by consolidation significantly increase the contaminant transport rate. In addition, the numerical simulations revealed that active capping with Reactive Core Mat (RCM) significantly decelerates consolidation-induced contaminant transport.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.237-240
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• 2002

In this W, a NiSi technology suitable for sub-100nm CMOS sevice is proposed. It seems that capping layer has little effect on the sheet resistance and junction leakage current when there is no thermal treatment. However, there happened agglomeration and drastic increase of Junction leakage current without capping layer. In other word, capping layer especially TiN capping layer is highly effective in suppressing thermal effect. It is shown that the sheet resistance of 0.12${\mu}{\textrm}{m}$ linewidth and shallow p+/n junction with NiSi were stable up to 700 t /30 minute thermal treatment.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.245-248
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• 2002

In this paper, the influence of Si surface damage on the NiSi formation has been characterized. The silicon surface is damaged using ion beam type spotter. Then, the effect of H2 anneal and TiN capping layer on the damaged has also been analyzed. The sheet resistance of NiSi formed on damaged Si increased rapidly as the damaging time increases while thermal stability of damaged NiSi was stabler than the undamaged one. In the case when H\ulcorner anneal and TiN capping layer were applied together, the characteristics of NiSi shows a little improvement of the sheet resistance.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.719-724
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• 1994

This paper describes a hybrid surface-based method for smooth 3D surface approximation to a sequence of 2D cross sections. The resulting surface is a hybrid G $^{1}$ surface represented by a mesh of triangular and rectangular Bezier patches defined on skinning, branching, or capping regions. Each skinning region is approximated with a closed B_spline surface, which is transformed into a mesh of Bezier patches. Triangular G $^{1}$ surfaces are constructed over brabching and capping regions such that the transitions between each capping regions such that the transitions between each triangular surface and its neighboring skinning surfaces are G $^{1}$ continuous. Since each skinning region is represented by an approximated rectangular C $^{2}$ suface instead of an interpolated trctangular G $^{[-1000]}$ surface, the proposed method can provide more smooth surfaces and realize more efficient data reduction than triangular surfacebased method.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.26-27
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• 2006

Capping mechanisms during the compaction of pharmaceutical powders were explored. Both experimental and numerical investigations were performed. For the experimental study, an X-ray Computed Microtomography system has also used to examine the internal failure patterns of the tablets produced using a compaction simulator. Finite element (FE) methods have also been used to analyse the powder compaction. The experimental and numerical studies have shown that the shear bands developed at the early stage of unloading appear to be responsible for the occurrence of capping. It has also been found that the capping patterns depend on the compact shape.

• Proceedings of the Korean Magnestics Society Conference
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• 2003.06a
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• pp.72-73
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• 2003

• Journal of the Korean GEO-environmental Society
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• v.17 no.10
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• pp.33-43
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• 2016

The determination of in-situ capping materials is one of the most important factors to design in-situ capping in order to protect capping materials from erosion. Previous studies have established relationship between the velocity induced by wave energy and effective diameter of sediments, but they are mostly empirical and numerical researches which is too complicated for field engineers to analyze the erosion of in-situ capping materials. This study provides simple analytical solutions and reliability based on hydraulic model test results. Experimental results show that measured flow velocities with respect to depth induced by wave energy are almost the same as estimated velocities and the erosion resistances of the different effective particle diameters can be estimated.