• Journal of Korean Society on Water Environment
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• v.28 no.1
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• pp.148-156
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• 2012

In this research, the application of carbon nanotubes (CNTs) modified PVDF (polyvinylidene fluoride) membrane was tested as a simply and beginning attempt to overcome membrane fouling because CNTs importantly affect the transport of natural organic matter (NOM). Suwannee River fulvic acid (SRFA) as the representative of NOM was selected and its sorption results with single-walled CNT (SWCNT), multi-walled CNT (MWCNT), and oxidized MWCNT (O-MWCNT) were obtained through the batch experiment. SRFA sorption isotherms had a strong nonlinearity and its sorption capacity followed the order O-MWCNT < MWCNT < SWCNT. The adsorbed mass of SRFA on each CNT decreased as a function of pH due to their charge repulsion. For the CNT-PVDF membrane filtration experiments, the suspended CNT solution (10 mg/40 mL) was incorporated into $0.45{\mu}m$-PVDF membrane and 5 mg/L of SRFA solution was monitored using UV detector connected with high pressure pump after passing through CNT-PVDF membrane. The SRFA removal efficiency by MWCNT-PVDF membrane was the strongest among other modified membranes. This suggests that the CNT modified microfiltration (MF) membrane might effectively and selectively apply to treat the contaminated water including organic compounds in the presence of NOM.

• Journal of Soil and Groundwater Environment
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• v.14 no.6
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• pp.95-100
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• 2009

Strategies incorporating more efficient energy use into remediation of contaminated sites, which are those of important elements in green remediation, are developed and discussed in this work. Firstly, from several case studies of remedial actions in Korea, thermal desorption and/or in-situ method including pump-and-treat were found energy intensive and soil washing less intensive. In order to use energy efficiently and minimize use of fossil fuels during land revitalization process, it is necessary to optimize energy intensive systems, to use low energy remediation systems (such as bioremediation), and to integrate renewable energy sources. Furthermore, economic incentive systems such as subsidy need to be adopted if renewable energy sources are incorporated into remediation of contaminated sites.

• Journal of Environmental Science International
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• v.28 no.5
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• pp.495-502
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• 2019

This study was conducted to investigated the possibility of inactivating wilt germs (Fusarium oxysporum f. sp. radicis lycopersici) using Dielectric Barrier Discharge (DBD) plasma in a hydroponic system. Recirculating hydroponic cultivation system for inactivation was consisted of planting port, LED lamp, water tank, and circulating pump for hydroponic and DBD plasma reactor. Two experiments were conducted: batch and intermittent continuous process. The effect of plasma treatment on Total Residual Oxidants (TRO) concentration change, Fusarium inactivation and growth of lettuce were investigated. In the batch experiment, most of the Fusarium was inactivated at a TRO concentration of 0.15 mg/L or more at four-day intervals. There was no change in lettuce growth after two times of plasma treatment for one week. The intermittent continuous experiment consisted of 30-minute, 60-minute, and 90-minute plasma treatment in 2 day intervals and 30-minute treatment a one-day; most of the Fusarium was inactivated only by treatment for 30-minute every two days. However, if inactivation under $10^1CFU/mL$ is required, it will be necessary to treat for 60 minutes in 2 day intervals. The plasma treatment caused no damage to the lettuce, except the 30 min plasma treatment ay the one-day interval. It was considered that the residual TRO concentration was higher than that of the other treatments.

• Journal of Gastric Cancer
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• v.20 no.3
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• pp.337-343
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• 2020

Distal gastrectomy with Billroth I or II reconstruction may cause duodenogastroesophageal reflux (DGER), thereby resulting in digestive or respiratory symptoms. The mainstay of treatment is medication with proton pump inhibitors. However, these drugs may have limited effects in DGER. Laparoscopic fundoplication has been proven to be highly effective in treating gastroesophageal reflux disease (GERD), but it cannot be performed optimally for GERD that develops after gastrectomy. We report the case of a 72-year-old man with a history of distal gastrectomy and Billroth I anastomosis due to early gastric cancer. GERD due to bile reflux occurred after surgery and was refractory to medical therapy. The patient underwent Roux-en-Y conversion from Billroth I gastroduodenostomy and hiatal hernia repair with only cruroplasty. Fundoplication was not performed. His symptoms improved significantly after the surgery. Therefore, laparoscopic hiatal hernia repair and Roux-en-Y conversion can be an effective surgical procedure to treat medically refractory DGER after Billroth I gastrectomy.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.261-266
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• 2001

Three innovative technologies to remediate trichloroethylene (TCE) in situ were (or currently are being) evaluated at a TCE-contaminated groundwater site at Edwards Air Force Base (AFB), California. The three technologies all make use of groundwater recirculation to obviate the need to pump contaminated groundwater to the surface fer treatment. The first technology, which implements aerobic cometabolic bioremediation to destroy TCE in situ, successfully reduced dissolved TCE concentrations from above 1 mg/L to 20-30 $\mu\textrm{g}$/L. The second technology, in-well vapor stripping (IWVS), is capable of treating dissolved TCE at concentrations in the tens to hundreds of mg/L. Finally, the third technology, bioenhanced in-well vapor stripping (BEHIVS): is a combination of the first two technologies, and is designed to reduce very high levels of TCE (tens to hundreds of mg/L) to concentrations that meet regulatory requirements 5 $\mu\textrm{g}$/L). Results of field evaluations of tile first two technologies are presented, and the design of the BEHIVS system. as well as model predictions of BEHIVS performance and the current status of the technology field evaluation. is discussed.

• Journal of Korea Multimedia Society
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• v.18 no.2
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• pp.207-217
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• 2015

A multi-cup electric cupping system (MECS) was proposed, based on the ancient cupping method. MECS consisted of several cups that could be used simultaneously to treat 85 lumbago patients. Each cup was equipped with its own pump and pressure-monitoring system. The vacuum pressure of the cups was controlled using fuzzy logic. Through automated control of the vacuum pressure, long-term relief of muscle tightness was achieved. To develop a scientific foundation for this alternative treatment, we compared the Oswestry Disability Index (ODI) scores from conventional basic cupping to the ODI scores for our proposed MECS. The ODI scores using MECS decreased from $11.71{\pm}1.61$ before treatment to $4.81{\pm}1.48$ and $1.87{\pm}1.61$ after three and five treatments, respectively. The improvement rate in the ODI scores using MECS after three treatments was higher than that achieved by basic cupping. These results, combined with the convenience offered by enhanced information technology and fuzzy logic capabilities, should increase the efficiency of this device, and facilitate the opportunity to further explore the potential of Oriental medical practices.

• Journal of Biomedical Engineering Research
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• v.26 no.4
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• pp.193-197
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• 2005

Shunt valves used to treat patients with hydrocephalus were tested to investigate influence of intracranial pressure pulsation on their flow control characteristics. Five commercial shunt valves were tested in the flow loop that simulates pulsed flow under pressure pulsation. As 20cc/hr of flow rate was adjusted at a constant pressure, application of $40mmH_2O$ of pressure pulse increased the flow rate by $67.9\%.$ As a 90cm length catheter was connected to the valve outlet, increase in the flow rate was substantially reduced to $17.5\%.$ As the flow rate was adjusted to 40cc/hr at a constant pressure, increase in the flow rate was $51.1\%$ with the same pressure pulsation of $40mmH_2O$. The results indicated that pressure-flow control characteristics of shunt valves implanted above human brain ventricle is quite different from those obtained by syringe pump test at constant pressures right after manufacture. The influence of pressure pulsation was observed to be more significant at low flow rate and the flexibility of the outlet silicone catheter was estimated to significantly reduce flow increase due to pressure pulsation.

• Journal of Biomedical Engineering Research
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• v.23 no.5
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• pp.391-395
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• 2002

Shunt valves used to treat patient with hydrocephalus were numerically simulated to investigate influence of pressure pulsation on their flow control characteristics. We modeled flow orifice through the shunt valve and imposed pulsating pressure and valve diaphragm movement to compute flow through the valve. The results of our study indicated that flow rates increased more than 40% by introducing pressure pulsation and diaphragm movement on the shunt valve. Our results demonstrate the pressure-flow control characteristics of shunt valves implanted above human brain may be quite different from those obtained by syringe pump test just after manufacture that induces uniform pressure.

• Journal of the Korean Geotechnical Society
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• v.18 no.4
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• pp.349-356
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• 2002

In this research, phenol was selected as a representative hydrophilic organic compound and phenanthrene as a representative hydrophobic organic contaminant in petroleum. Fine-grained soil which was manufactured artificially in laboratory was contaminated and EK remediation tests were executed. Also, in order to increase removal efficiency, the surfactant that had been used with improvement technique at the pump-and-treat was used by enhanced method. In the test, the phenol which has high solubility is easily removed, but phenanthrene which has low solubility is almost not. Also, it seems to be the delay phenomenon that the phenanthrene is accumulated near the cathode department vicinity at the enhanced technique which applied the surfactant, but the removal efficiency increases as the surfactant concentration increases. By the test which increases with time, the enhanced method with increasing time is more efficient than the method with increasing surfactant.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.5
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• pp.417-430
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• 2019

The policies developed for the treatment of Helicobacter pylori infection in adults may not be the most suitable ones to treat children and adolescents. Methods used to treat children and adolescents in Europe and North America may not be appropriate for treating children and adolescents in Korea due to differences in epidemiological characteristics of H. pylori between regions. Moreover, the agreed standard guidelines for the treatment of H. pylori infection in children and adolescents in Korea have not been established yet. In this study, the optimal treatment strategy for H. pylori infection control in children and adolescents in Korea is discussed based on these guidelines, and recent progress on the use and misuse of antimicrobial agents is elaborated. Non-invasive as well as invasive diagnostic test and treatment strategy for H. pylori infection are not recommendable in children aged less than ten years or children with body weight under 35 kg, except in cases of clinically suspected or endoscopically identified peptic ulcers. The uncertainty, whether enough antimicrobial concentrations to eradicate H. pylori can be maintained when administered according to body weight-based dosing, and the costs and adverse effects outweighing the anticipated benefits of treatment make it difficult to decide to eradicate H. pylori in a positive noninvasive diagnostic test in this age group. However, adolescents over ten years of age or with a bodyweight of more than 35 kg can be managed aggressively as adults, because they can tolerate the adult doses of anti-H. pylori therapy. In adolescents, the prevention of future peptic ulcers and gastric cancers is expected after the eradication of H. pylori. Bismuth-based quadruple therapy (bismuth-proton pump inhibitor-amoxicillin/tetracycline-metronidazole) with maximal tolerable doses and optimal dose intervals of 14 days is recommended, because in Korea, the antibiotic susceptibility test for H. pylori is not performed at the initial diagnostic evaluation. If the first-line treatment fails, concomitant therapy plus bismuth can be attempted for 14 days as an empirical rescue therapy. Finally, the salvage therapy, if needed, must be administered after the H. pylori antibiotic susceptibility test.