• Corrosion Science and Technology
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• v.15 no.6
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• pp.303-310
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• 2016

The tap water used in Seoul was found to be corrosive. Its corrosivity was effectively reduced by that the additions of alkali agent such as NaOH, $Ca(OH)_2$ and corrosion inhibitor such as $H_3PO_4$. For the corrosion test, carbon steel pipe 50 m long was exposed to the drinking water produced by a pilot plant at $36.5^{\circ}C$, similar to the existing process where it takes about 20 minutes to reduce the initial chlorine content of 0.5 mg/L to 0.05 mg/L. $CO_2$ and $Ca(OH)_2$ was added not only to control the Langelier index (LI) above -1.0 and but also, to increase the duration time of residual chlorine by about 6 times. The persistence effect of residual chlorine was in the order of $H_3PO_4$ > $Ca(OH)_2$ > NaOH. Measurements of weight loss showed that corrosion inhibition was effective in order of $Ca(OH)_2$ > $H_3PO_4$ > NaOH > no addition, where the concentrations of $Ca(OH)_2$ and phosphate were 5 ~ 10 mg/L (as $Ca^{2+}$) and 1 mg/L (as $PO{_4}^{3-}$), respectively.

• Journal of Wetlands Research
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• v.11 no.2
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• pp.55-66
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• 2009

The increase of pollutant loadings from nonpoint sources affect the water quality of the major rivers in Korea. Consequently, the need for managing the nonpoint source (NPS) pollution becomes the main concern of the Korean Ministry of Environment (MOE). Recently, the policy was changed from pollutant concentration-restricting approach to the total maximum daily load (TMDL) approach to improve the water quality and protect the aquatic ecosystem. Part of the program is the construction of Best Management Practice (BMP) pilot facilities basically to control NPS. Most of the BMPs adopted were foreign technologies which could not be properly employed in the country due to some limitations such as climate, watershed characteristics, etc. In other words, to be able to apply the BMPs, research on its applicability is necessary. In this study, a three-year monitoring has been conducted to assess the treatment performance of the BMP installed in highway toll plaza and parking lot. The data gathered aid in the characterization of NPS pollutants in runoff and estimation of the pollutant removal efficiency of the BMP. The results will be used for the future implementation of BMP in different land uses as well as for the determination of optimum operation and maintenance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.10C
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• pp.1355-1362
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• 2004

In this paper, we present the performance analysis of a multi-path searcher operating over Rayleigh fading channels when multiple transmit antennas are employed in the down-link of W-CDMA system. The simulation results for the receiver operating characteristics (ROC) for 1, 2, and 4 transmit antennas are presented to corroborate the theoretical analyses. We also propose a procedure to find the optimum parameters of double-dwell serial searcher according to the number of the multiple transmit antennas. Our analyses and simulations indicate that post-detection integration is not necessary when the number of transmit antennas is more than two. Finally, we found that increasing transmit diversity order does not necessarily improve the detection performance when the received pilot signal strength is relatively low. Therefore, this gives us a practical criterion on increasing transmit diversity order.

• KEPCO Journal on Electric Power and Energy
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• v.1 no.1
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• pp.115-120
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• 2015

$K_2CO_3$-based dry regenerable sorbents were prepared by spray-drying techniques to improve mass produced $K_2CO_3-Al_2O_3$ sorbents (KEP-CO2P, hereafter), and then tested for their $CO_2$ sorption capacity by a $2,000Nm^3/h$ (0.5 MWe) $CO_2$ capture pilot plant built for Unit 3 of the Hadong thermal power station in 2010. Each of the sample sorbents contained 35 wt.% $K_2CO_3$ as the active materials with various support materials such as $TiO_2$, MgO, Zeolite 13X, $Al_2O_3$, $SiO_2$ and hydrotalcite (HTC). Their physical properties and reactivity were tested to evaluate their applicability to a fluidized-bed or fast transport-bed $CO_2$ capture process. The $CO_2$ sorption capacity and percentage utilization of $K_2CO_3$-MgO based sorbent, Sorb-KM2, was $8.6g-CO_2/100g$-sorbents and 90%, respectively, along with good mechanical strength for fluidized-bed application. Sorbs-KM2 and KT were almost completely regenerated at $140^{\circ}C$. No degradation of Sorb-KM by $SO_2$ added as a pollutant in flue gas was observed during a cycle test.

• Journal of Korean Society on Water Environment
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• v.23 no.2
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• pp.193-200
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• 2007

The AOPs research defined by creating a sufficient amount of OH radicals from the dissolution of organic materials through photoxidation and research for a complete elimination of residual organic materials by membrane are actively ongoing. This research focuses on the hybrid processing of AOPs and M/F membrane to dissolve and eliminate organic chemicals in drinking water which are suspected of carcinogens. For this purpose, underground water was used as a source of drinking water for the hybrid processing of AOPs oxidation and M/F membrane, and a pilot plant test device was installed indoor. Carcinogenic chemicals of VOCs and pesticide were artificially mixed with the drinking water, which was then diluted close to natural water in order to examine treatment efficiency and draw optimal operation conditions. The samples used for this experiment include four chemicals phenol, chloroform, in VOCs and parathion, carbaryl in pesticide. As a result of the experiments conducted with simple, and compound solutions, the conditions to sufficiently dissolve and eliminate carcinogenic chemicals from the hybrid processing of where carcinogens were artificially added are : (hydrogen peroxide) prescribed solution 100 mg/L under pH 5.5~6.0, and the temperature $12{\sim}16^{\circ}C$, at the normal temperature and pressure. $d-O_3$ volume of 5.0 ppm and above and 30-40 minutes of reaction time are most appropriate and using MF/UF for membrane was ideal.

• Journal of Animal Environmental Science
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• v.5 no.3
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• pp.189-196
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• 1999

Anaerobic digestion is a naturally occuring microbial process involving the decomposition of organic materials such as livestock manure. This study explores the effect of the operating conditions, HRT (Hydraulic Retention Time) and feeding frequency on treatment efficiency for digestion of pig slurry, which has been one of most difficult organic waste for proper treatment in livestock production industry in Korea at the present time. The pilot-scale CSTR of 5 m3 in volume was designed. manufactured, and operated at the temperature of 35$\pm$1$^{\circ}C$. The digester was designed to hydraulically stir for complete mixing and to supply heat from the water bath to maintain mesophilic temperature. The HRT of the digester for Test 1 and Test 2, and Test 3 was set for 17 days and 13 days respectively and pig slurry was fed once a day with 300$\ell$ each for Test 1 and Test 3, while twice with 150$\ell$each for Test 2. Test 2 showed better performance by increase of 4% in VS removal efficiency and 5% in biogas production rate. This is mainly attributed to smaller temperature drop by feeding frequently with half amount, which eventually led to lesser impact on anaerobic mocrobes in the digester. Test 2 maintained optimum pH 7.8 which uplifted the activaton of sulfur-reduction bacteria, alkalinity of around 4,000mg/$\ell$, VA of over 3,000mg/$\ell$ for whole period of experiment. Further research may require to provide the practical operation strategy of anaerobic treatment system for treatment of pig slurry.

• Archives of Plastic Surgery
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• v.48 no.5
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• pp.559-567
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• 2021

The potential to differentiate into different cell lines, added to the easy and cost-effective method of extraction, makes adipose-derived stem cells (ADSCs) an object of interest in lymphedema treatment. Our study's goal was to conduct a comprehensive systematic review of the use of ADSCs in lymphatic tissue engineering and regeneration. On July 23, 2019, using PubMed/MEDLINE, Cochrane Clinical Answers, Cochrane Central Register of Controlled Trials, and Embase databases, we conducted a systematic review of published literature on the use of ADSCs in lymphatic tissue engineering and regeneration. There were no language or time frame limitations, and the following search strategy was applied: ((Adipose stem cell) OR Adipose-derived stem cell)) AND ((Lymphedema) OR Breast Cancer Lymphedema). Only original research manuscripts were included. Fourteen studies fulfilled the inclusion criteria. Eleven studies were experimental (in vitro or in vivo in animals), and only three were clinical. Publications on the topic demonstrated that ADSCs promote lymphangiogenesis, and its effect could be enhanced by modulation of vascular endothelial growth factor-C, interleukin-7, prospero homeobox protein 1, and transforming growth factor-β1. Pilot clinical studies included 11 patients with breast cancer-related lymphedema, and no significant side effects were present at 12-month follow-up. Literature on the use of ADSCs in lymphatic tissue engineering and regeneration demonstrated promising data. Clinical evidence is still in its infancy, but the scientific community agrees that ADSCs can be useful in regenerative lymphangiogenesis. Data collected in this review indicate that unprecedented advances in lymphedema treatment can be anticipated in the upcoming years.

• Journal of Navigation and Port Research
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• v.45 no.3
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• pp.87-94
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• 2021

The IMO has adopted emission standards that strictly restrict the use of bunker C oil for vessels. Accordingly, research and bunkering pilot projects for LNG fueled ships are being actively carried out, which is expected to substantially reduce environmental pollution. In this study, we have adopted the turret moored Floating LNG Bunkering Terminal (FLBT) designed to receive the LNG from LNGCs and to transfer LNG to LNG bunkering shuttles in ship to ship moored condition. Numerical simulations have been performed with a 1-year return period of wind, wave, and current. Damping values of numerical model were adjusted from the results of model tests to obtain accurate simulation results. The results confirm safe berthing operation during the 1-year return period of environmental condition. Safety depends on the direction of environment, with increasingly stable operation facilitated by the application of heading-control function of FLBT to avoid beam-sea conditions.

• Journal of Gastric Cancer
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• v.19 no.2
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• pp.173-182
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• 2019

Purpose: Intraoperative peritoneal washing cytology (PWC) is used to determine treatment strategies for gastric cancer with suspected serosal invasion. However, a standard staining method for intraoperative PWC remains to be established. We evaluated the feasibility of a rapid and simple staining method using Shorr's stain for intraoperative PWC in advanced gastric cancer. Materials and Methods: Between November 2012 and December 2014, 77 patients with clinical T3 or higher gastric cancer were enrolled. The sensitivity, specificity, and concordance between the Shorr staining method and conventional Papanicolaou (Pap) staining with carcinoembryonic antigen (CEA) immunohistochemistry (IHC) were analyzed. Results: Intraoperative PWC was performed laparoscopically in 69 patients (89.6%). The average time of the procedure was 8.3 minutes, and the average amount of aspirated fluids was 83.3 mL. The average time for Shorr staining and pathologic review was 21.0 minutes. Of the 77 patients, 16 (20.7%) had positive cytology and 7 (9.1%) showed atypical findings; sensitivity and specificity were 73.6% and 98.2% for the Shorr method, and 78.9% and 98.2% for the Pap method with CEA IHC, respectively. Concordance of diagnosis between the 2 methods was observed in 90.9% of cases (weighted ${\kappa}$ statistic=0.875) and most disagreements in diagnoses occurred in atypical findings (6/7). In overall survival, there was no significant difference in C-index between the 2 methods (0.459 in Shorr method vs. 0.458 in Pap with CEA IHC method, P=0.987). Conclusions: Shorr staining could be a rapid and reliable method for intraoperative PWC in advanced gastric cancer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.1
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• pp.118-123
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• 2021

This study was conducted to evaluate plant proteins as a replacement for a fishmeal diet in the rearing of coho salmon Oncorhynchus kisutch. Twelve groups of 20 fish averaging 34.0±0.62 g were randomly distributed into 12 rectangular tanks (250 L). Four experimental diets included a control diet containing 60% fishmeal (Control), and three other diets that replaced 20% of fishmeal with soy protein concentrate (SPC), fermented soybean protein concentrate (F-SPC), and enzyme-processed soy protein concentrate (E-SPC). At the end of the feeding trial, fish that were fed Control, SPC and E-SPC diets showed significantly higher weight gain, specific growth rate, feed efficiency, and protein efficiency ratio than those that were fed F-SPC diet. However, there were no significant differences among the fish that were fed Control, SPC, and E-SPC diets. No significant differences were observed in crude protein, crude lipid, and ash of whole body among the fish that were fed all the diets. Therefore, these results indicated that 20% of fishmeal could be replaced by E-SPC or SPC without any adverse effects on the growth performance of coho salmon.