• Journal of Korean Dental Science
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• v.11 no.1
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• pp.14-20
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• 2018

Purpose: The purpose of this study is to measure and compare the removal torques of different cements applied in attachments of zirconia restorations on titanium (Ti) abutments fitted with retrievable cement-type slot (RCS) on the lingual side for the better retrievablity by use of a slot driver. Materials and Methods: Three types of cements were used in the experiment: two permanent cements in $RelyX^{TM}$ U200 (RU) (3M ESPE) which is a resin cement and $FujiCem^{TM}$ (FC) (GC) which is a resin-modified glass ionomer cement, and a temporary cement in $Freegenol^{TM}$ temporary cement (TC) (GC). Measurements of removal torques were conducted as follows; an attached sample was fixed on the equipment customized for the experiment; a slot driver was connected to a MGT12 (Mark-10 Corp.), a torque measurement instrument; the sample had the driver fitted to its RCS and then was rotated until the it was removed; and finally, the maximum torque value was recorded. Result: As for the removal torque measurement results, the average values were $47.9{\pm}2.6Ncm$ for RU, $43.4{\pm}1.5Ncm$ for FC, and $20.9{\pm}1.0Ncm$ for TC. The statistical analysis using Kruskal-Wallis test yielded the significance probability of P<0.05 (P=0.002), which confirmed the presence of significant differences between the three groups. Conclusion: All three cements exhibit clinically acceptable levels of removal torque when applied to an upper zirconia implant restoration fitted with a lingual slot, with RU and FC, the two permanent cements, having the significantly higher values than that of TC, the temporary cement.

• Journal of Biosystems Engineering
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• v.41 no.3
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• pp.201-207
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• 2016

Purpose: A water-spraying type automatic glochids removal system for cactus (Opuntia humifusa) stem was developed, and its performance was evaluated. The system was developed to reduce intensive human labor in removing glochids from cactus stem skin without inducing damage prior to further processing into value-added products. Methods: The developed system consists of conveyor and water-spraying systems. The conveyor system delivers cactus stems through water-spraying compartments and finally to a collecting box. In order to remove the glochids, rotating nozzles spray water over all areas (i.e., front and back faces and sides) of the cactus skin under controlled water pressure. Operating conditions such as conveyor speed, water pressure, angle of water-spraying nozzles, distance between conveyor belt and rotating nozzles, and angle of cactus flipping slide were adopted from our previous study and applied on the system design and manufacturing. The performance of glochids removal was evaluated by counting the number of glochids on the cactus stem before and after processing on the system. Results: The developed system performed efficiently and effectively under the pre-studied operating conditions except for the angle of cactus flipping slide. The new system had a glochids removal ratio of 94.1% without damaging the cactus skin. Considering the original number (approximately 30-60) of glochids, the remaining number was low (1-4), and most of them were found at the side edge of the cactus stem. This system can remove glochids from 360 cactus stems in 1 hr regardless of cactus size. Conclusions: The performance of the new system in glochids removal without damaging cactus skin is superior to any other existing device (i.e., brush type, rubber-friction type, and agitation type). The system is expected to be applied in cactus (O. humifusa) processing facilities.

• Journal of Korean Clinical Nursing Research
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• v.18 no.2
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• pp.296-306
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• 2012

Purpose: This study was done to compare the physical injury, emotional response and unplanned self-removal of medical devices in patients with physical restraints and patients not restrained. Methods: Eighty patients admitted to the intensive care unit (ICU) of a university hospital in Seoul participated in this study. Forty patients made up each group and the group not restrained was matched with the restraint group for age and history of smoking and alcohol consumption. Data on occurrence of physical injury, intensity of anxiety, stage of agitation and unplanned self-removal of medical devices were collected by observation and medical chart review using a structured instrument. Statistical processing of collected data was done with the SPSS WIN 17.0 program. Results: The physically restrained group experienced more physical injuries and recorded significantly higher levels of anxiety and agitation than the unrestrained group. However, there were no significant differences between the groups in occurrence of unplanned self-removal of medical devices. Conclusion: Results indicate a need for critical care nurses to carefully monitor physical injuries and emotional responses of physically restrained patients and to develop nursing interventions to prevent adverse effects associated with restraint use. There is also a need to develop patient safety guidelines when using physical restraints.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.88-89
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• 2009

In this paper, we investigated about wet cleaning effect as deep trench formation methods for Power chip devices. Deep trench structure was classified by two methods, PSU (Poly Stick Up) and Non-PSU structure. In this paper, we could remove residue defect during wet. cleaning after deep trench etch process for non-PSU structure device as to change wet cleaning process condition. V-SEM result showed void image at the trench bottom site due to residue defect and residue component was oxide by EDS analysis. In order to find the reason of happening residue defect, we experimented about various process conditions. So, defect source was that oxide film was re-deposited at trench bottom by changed to hydrophobic property at substrate during hard mask removal process. Therefore, in order to removal residue defect, we added in-situ SCI during hard mask removal process, and defect was removed perfectly. And WLR (Wafer Level Reliability) test result was no difference between normal and optimized process condition.

• Particle and aerosol research
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• v.9 no.4
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• pp.239-246
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• 2013

The purpose of this study is to determine the feasibility of dry-type desulfurization process for actual application to coal-fired power plant. We used actual exhaust gas from Facility Y, Plant #2 to fabricate a demo-scale testing device to attempt to improve the efficiency of desulfurization. A spout-bed circulating dry scrubber convergence system connecting turbo reactor with bag filter was devised, then analyzed for performance characteristics of $SO_2$ removal for Ca/S mole ratio, superficial gas velocity, and ammonia injection, and for secondary reaction characteristics of the non-reactive sorbent at the bag filter. As a result, the installation of spout-bed circulating dry scrubber convergence system showed better economy and efficiency for removing sulfur than the existing wet/semidry-type desulfurization process. In addition, the best efficiency for desulfurization occurred when connected to the bag filter, with differential pressure maintained at 150 $mmH_2O$.

• Journal of the Korean Society of Combustion
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• v.10 no.2
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• pp.1-8
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• 2005

Incomplete combustion due to quenching in a narrow confinement has been a major problem for realization of a reliable micro combustion device. In most micro combustors, effects of flows are absent in the quenching because the flow is laminar and no severe stretch is present. In such circumstance, quenching is caused either by heat loss or by removal of active radicals to the wall surface of the confinement. An experimental investigation was carried out to investigate the relative significance of these two causes of quenching of a premixed flame. A premixed jet burner with a rectangular cross section at the exit was built. At the burner exit, the flame stands between two walls with adjustable distance. The gap between the two walls at which quenching occurs was measured at different wall surface conditions. The results were analyzed to estimate the relative significance of heat loss to the wall and the removal of radicals at the surface. The measurements indicated that the quenching distance was independent of the wall surface characteristics such as oxygen vacancy, grain boundary, or impurities at low temperature. At high temperature, however, the surface characteristics strongly affect the quenching distance, implying that radical removal at the wall plays a significant role in the quenching process.

• Fisheries and Aquatic Sciences
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• v.13 no.2
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• pp.133-139
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• 2010

The effects of suspended solids size on culture water quality were determined in a commercial recirculating aquaculture system (RAS) for Japanese eel, Anguilla japonica. The particulate phase of the culture water was serially divided into six size fractions using 300, 200, 100, 75, 45, and 26 ${\mu}m$ pore size stainless sieves. The total, dissolved, and particulate nitrogen and phosphorus, and suspended solids for each fraction were determined. The concentration ranges in the fractions were: total nitrogen, 164-148 mg $L^{-1}$; total phosphorus, 20.4-15.5 mg $L^{-1}$; and total suspended solids, 8.1-6.1 mg $L^{-1}$. The concentration of total nitrogen and total phosphorus decreased significantly (P<0.05) with a 26 ${\mu}m$ and 200 ${\mu}m$ filter pore size, respectively. Nutrients from dissolved organic substances were much higher than from particulates. Analysis of particle size fractionation and its effects on water quality is useful to estimate removal efficiencies of a commercial effluent screening device for solid management and development of solid removal systems.

• Journal of Korean Society on Water Environment
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• v.22 no.2
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• pp.258-263
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• 2006

ANAMMOX (Anaerobic ammonium oxidation) reactor, which was cultivated ANAMMOX bacteria in mesophilic condition ($35^{\circ}C$), was operated to investigate the effects of temperature. In $20{\sim}30^{\circ}C$ of operation condition, which was assumed as field-temperature, total N removal and $NH_4-N$ removal rate were declined from about 2.50 and $1.27kg\;N/{m^3}_{reactor}-day$ (0.06 and 0.03 kg N/kgVSS/day) to 1.62 and $0.41kg\;N/{m^3}_{reactor}-day$ (0.04 and 0.01 kg N/kgVSS/day), In this range of temperature, ANAMMOX had very low activities but acid fermentation bacteria and denitrifiers, which were competitors of substrates, had high activities relatively. Though operation temperature was higher than inhibition condition for two months, ANAMMOX activities could not been recovered once they were inhibited by low temperature. This fact was resulted from very slow doubling time of ANAMMOX bacteria. This study shows that maintenance device of optimal temperature is necessary required in field application of ANAMMOX.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.41-44
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• 2003

As the device feature size is reduced to the deep sub-micron regime, the chemical mechanical polishing (CMP) technology is widely recognized as the most promising method to achieve the global planarization of the multilevel interconnection for ULSI applications. However, cost of ownership (COO) and cost of consumables (COC) were relatively increased because of expensive slurry. In this paper, the effects of different slurry composition on the oxide CMP characteristics were investigated to obtain the higher removal rate and lower non-uniformity. We prepared the various kinds of slurry. In order to save the costs of slurry, the original slurry was diluted by de-ionized water (DIW). And then, alunima abrasives were added in the diluted slurry in order to promote the mechanical force of diluted slurry.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.571-572
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• 2006

Tungsten CMP needs interconnect of semiconductor device ULSI chip and metal plug formation, CMP technology is essential indispensable method for local planarization. This Slurry development also for tungsten CMP is important, slurry of metal wiring material that is used present is depending real condition abroad. It is target that this research makes slurry of efficiency that overmatch slurry that is such than existing because focus and use colloidal silica by abrasive particle to internal production technology development. Compared selectivity of slurry that is developed with competitor slurry using 8" tungsten wafer and 8" oxide wafer in this experiment. And removal rate measures about density change of $H_2O_2$ and Fe particle. Also, corrosion potential and current density measure about Fe ion and Fe particle. As a result, selectivity find 83:1, and expressed similar removal rate and corrosion potential and current density value comparing with competitor slurry.