• Journal of Sensor Science and Technology
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• v.26 no.5
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• pp.306-313
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• 2017

An early detection of infiltration in veins is essential to minimize the injuries caused during infusion therapy, which is one of the most important tasks for nurses in clinical settings. We report that bioelectrical impedance analysis is useful in the early detection of infiltration at puncture sites. When infiltration was intentionally induced in the vein of a rabbit's ear, impedance parameters showed significant difference before and after infiltration. In particular, the relative resistance at 20 kHz in the vein of rabbit's ear reduced largely at infiltration, decreased slowly, and then stayed at a constant value. This indicates that the vein in the ear of the rabbit is small, and hence the infiltrated intravenous (IV) solution no longer accumulates after 3 minutes of infiltration. However, when infiltration was induced in the vein of a human's forearm, the relative resistance at 20 kHz decreased gradually over time. In the $R-X_c$ graph, the positions in infiltration induced in the rabbit's ear rapidly shifted before and after infiltration whereas the positions in infiltration induced in the human's forearm changed gradually during infiltration. Our findings suggest that bioelectrical impedance analysis is an effective method to detect the infiltration early in a noninvasive and quantitative manners.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.6
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• pp.1556-1571
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• 1993

Nitrogen oxides ($NO_x$) are air pollutants which are generated from the combustion of fossil fuels. Stage combustion is an effective method to reduce $NO_x$ emissions. The effects of $NO_x$ reduction by stage combustion in a pilot scale combustor(6.6kW) have been investigated using propane gas flames laden with NH$_{3}$ as Fuel-N. The results in this study are follows; (1) $NO_x$ emissions are dependent on the reducing environment of fuel-rich zone regardless of total air ratio. The maximum $NO_x$ reduction is at the stoichiometric ratio of 0.8 to 0.9 in the reducing zone. (2) $NO_x$ reduction is maximum when burnout air is injected at the point where the oxygen in reducing zone is almost consumed. (3) $NO_x$ reduction is dependent upon the temperature of reducing zone with best effect above 950.deg. C in the reducing zone. (4) The fuel stage combustion is more effective to reduce $NO_x$ formation in the wide range of stoichiometric ratio than two stage combustion. (5) The results of this study could be utilized mainly in a design strategy for low $NO_x$ emission from the combustion of high fuel-nitrogen in energy sources ratio than as an indication of the absolute levels of $NO_x$ which can be achieved by stage combustion techniques in large scale facilities.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.4
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• pp.459-469
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• 2009

It is well known that coagulation pretreatment can reduce foulants prior to membrane filtration. The purpose of this research was to investigate the effects of coagulation on fouling of ceramic microfiltration membrane($0.1 {\mu}m$) using pilot plant of $150m^3/day/train$ capacity. Train A membrane system has pretreatment process of ozonation and coagulation while train B has only coagulation. Two types of coagulation operation were investigated: back mixer(rapid mixing with or without slow mixing) which is a conventional mechanically stirred mixer and an inline static mixer. Ozone dose rate for train A was 1 mg/L and ozone contact time was 12 min. The coagulation dose(PACl 10% as $Al_2O_3$) rate was changed 20~40 mg/L according to experimental schedule. In this experimental conditions, the coagulation of back mixer type with rapid mixing(GT=72,000) and slow mixing(GT=45,000) was the best effective in reduction of ceramic membrane fouling regardless preozonation. Especially, the effect of inline static mixer was sensitive to change in water quality. Ozonation mainly affected irreversible fouling rather than reversible fouling in accordance with less adsorption of NOM on the membrane surface. Thus, the increase rate of the nomalized TMP(trans membrane pressure) at $25^{\circ}C$ for train A was relatively lower than that of train B under same coagulation process with same coagulant dosage. The best performance of ceramic membrane appeared in case of combined process with ozonation, therefore this integrated process is able to archive less coagulant dosing and secure a stability of ceramic membrane system.

• Applied Chemistry for Engineering
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• v.17 no.1
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• pp.58-61
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• 2006

The object of this study was to develop an advanced method for fluid flow and oxygen transmission and increase adhesive property of microorganism to waste plastic vessel that was made of microorganism media. Through lab scale experiments, we found the optimum packed media volume rate and method, and when the optimum condition was applied to pilot plant, we confirmed possibility of advanced treatment. The sewage that was used in the test was the sewage disposal facility established in C and K elementary schools, which utilized waste plastic media oxidation engineering method. Analysis showed that removal efficiency of organic matter, SS, T-N and T-P was very high, that the sewage disposal facility maintained stability of treatment when changeable load of raw sewage flowed in.

• Transactions of the Korean hydrogen and new energy society
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• v.15 no.4
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• pp.301-308
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• 2004

The methane reforming with $CO_2$ and steam for manufacture of synthesis gas over $Ni/ZrO_2$ catalyst was investigated. Mixed reforming carried out $CO_2$ dry reforming with $O_2$ and steam for development of DME process in pilot plant. To improve a catalyst deactivation by coke formation, the mixed reforming added carbon dioxide and steam as a oxidizer of the methane reforming was suggested. The result of experiments over commercial catalyst in $CO_2$ dry reforming has shown that the catalyst activity decrease rapidly after 20 hours. In case of $NiO-MgO/Al_2O_3$ catalyst, the deactivation of 20 percent after 30 hours was occurred. The activity of Ni/C catalyst still was not decreased dramatically after 100 hours. The effect of $H_2$ reforming with steam over $Ni/CO_2$ catalyst obtained the optimal conversion of methane and carbon dioxide, and could be produced synthesis gas at ratio of $H_2/CO$ under 1.5.

• Journal of Periodontal and Implant Science
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• v.42 no.5
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• pp.151-157
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• 2012

Purpose: Cyclooxygenase (COX) enzyme catalyzes the production of prostaglandins, which are important mediators of tissue destruction in periodontitis. Single nucleotide polymorphisms of $COX_2$ enzyme have been associated with increasing susceptibility to inflammatory diseases. The present study evaluates the association of two single nucleotide polymorphisms in $COX_2$ gene (-1195G>A and $8_{473}$C>T) with chronic periodontitis in North Indians. Methods: Both SNPs and their haplotypes were used to explore the associations between $COX_2$ polymorphisms and chronic periodontitis in 56 patients and 60 controls. Genotyping was done by polymerase chain reaction followed by restriction fragment length polymorphism. Chi-square test and logistic regression analysis were performed for association analysis. Results: By the individual genotype analysis, mutant genotypes (GA and AA) of $COX_2$-1195 showed more than a two fold risk (odds ratio [OR]>2) and $COX_2$ $8_{473}$ (TC and CC) showed a reduced risk for the disease, but the findings were not statistically significant. Haplotype analysis showed that the frequency of the haplotype AT was higher in the case group and a significant association was found for haplotype AT (OR, 1.79; 95% confidence interval, 1.03 to 3.11; P=0.0370) indicating an association between the AT haplotype of $COX_2$ gene SNPs and chronic periodontitis. Conclusions: Individual genotypes of both the SNPs were not associated while haplotype AT was found to be associated with chronic periodontitis in North Indians.

• Journal of the Korean Ceramic Society
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• v.40 no.10
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• pp.936-942
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• 2003

In order to develop glass formulations for vitrifying Low-and Intermediate-Level radioactive Wastes (LILW) from nuclear power plants of Korea Hydro & Nuclear Power (KHNP) Co., Ltd., promising glass formulations were selected based on glass property model predictions for viscosity, electrical conductivity and leach resistance. Laboratory measurements were conducted to verify the model predictions. Based on the results, the models for electrical conductivity, US DOE 7-day Product Consistency Test (PCT) elemental release, and pH of PCT leachate are accurate for the LILW glass formulations. However, the model for viscosity was able to provide only qualitative results. A leachate conductivity test was conducted on several samples to estimate glass leach resistance. Test results from the leachate conductivity test were useful for comparison before PCT elemental release results were available. A glass formulation K11A meets all the KHNP glass property constraints, and use of this glass formulation on the pilot scale is recommended. Glass formulations K12A, K12B, and K12E meet nearly all of the processing constraints and may be suitable for additional testing. Based on the comparison between the measured and predicted glass properties, existing glass property models may be used to assist with the LILW glass formulation development.

• Journal of Digital Convergence
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• v.14 no.1
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• pp.437-443
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• 2016

Purpose of this study was to develop a self-care program for patients with asthma and test its effects on self-efficacy, compliance, Quality of Life. One group pretest and posttest design was used to test the effects of the intervention. Sixteen asthma patients were recruited conveniently from C university hospital. Date were collected from February 1st to Spring 30th, 2011. Self-care program was composed asthma related education and demonstration of usage of MID & PEFR. The data were analyzed using Wilcoxon signed Rank test by SPSS 18.0. There was a significant increased in self-efficacy(Z=-3.26, p=.001), compliance(Z=-3.52, p<.001), QOL(Z=-3.41, p=.001). Based on data, we recommened the refinement of the intervention in the following areas for future studies: duration, research design, sample size.

• Macromolecular Research
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• v.17 no.6
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• pp.378-387
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• 2009

This research compared three methods for producing and processing nanocomposite polypropylene filament yarns with permanent antimicrobial efficiency. The three methods used to mix antimicrobial agents based on silver nano particles with PP were as follows: 1) mixing of PP powder and inorganic nanocomposite filler with the appropriate concentration using a twin-screw extruder and preparing granules, 2) method 1 with a singlerather than twin-screw extruder, and 3) producing the masterbatch by a twin-screw extruder and blending it with PP in the melt spinning process. All pure polypropylene samples and other combined samples had an acceptable spinnability at the spinning temperature of $240^{\circ}C$ and take-up speed of 2,000 m/min. After producing as-spun filament yarns by a pilot plant, melt spinning machine, the samples were drawn, textured and finally weft knitted. The physical and structural properties (e.g., linear density, tenacity, breaking elongation, initial modulus, rupture work, shrinkage and crystallinity) of the as-spun and drawn yarns with constant and variable draw ratios (the variable draw ratio was used to gain a constant breaking elongation of 50%) were investigated and compared, while DSC, SEM and FTIR techniques were used to characterize the samples. Finally, the antibacterial efficiency of the knitted samples was evaluated. The experimental results revealed that the crystallinity reduction of the as-spun yarn obtained from method 1 (5%) was more than that of method 2 (3%), while the crystallinity of the modified as-spun yarns obtained with method 3 remained unchanged compared to pure yarn. However, the drawing procedure compensated for this difference. By applying methods 2 and 3, the drawing generally improved the tenacity and modulus of the modified fibers, whereas method 1 degraded the constant draw ratio. Although the biostatic efficiency of the nanocomposite yarns was excellent with all three methods, the modified fabrics obtained from methods 1 and 2 showed a higher bioactivity.

• Asian Oncology Nursing
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• v.10 no.2
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• pp.180-190
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• 2010

Purpose: The purpose of this study was to compare the improvement and maintenance effects of foot reflexology (FR) on sensations after breast cancer surgery with those of lavender foot bath (LFB). Methods: Using a single-blind design, both 18 women to receive 20-min FR by trained experts and 14 women to soak feet in $40^{\circ}C$ foot tub water with 5 drop lavender essential oil, 15-min were intervened every two days. Repeated measures were taken pre 1st-(baseline-4th op. day), pre 3rd-(2nd data), and pre 5th-intervention (3rd data) with following up at 1-week after 5th intervention (4th data). The reliable translated Korean version of Baron's Breast Sensation Assessment Scale was used to assess sensations after breast cancer surgery (SABCS) characterized by prevalence, frequency, severity, and distress. Results: A significant difference between baseline and the 3rd, and a decrease tendency from baseline to the 3rd were observed for the severity and distress in FR and for the prevalence and severity in LFB. A significant or important decrease tendency between the 3rd and the 4th were observed for the severity and distress in FR and for the severity in LFB. Conclusion: Iterative FR has the improvement and maintenance effects on the severity and distress while LFB has only those on the severity.