• Journal of Korean Society for Atmospheric Environment
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• v.28 no.3
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• pp.233-248
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• 2012

The national emission from energy sector accounted for 84.7% of all domestic emissions in 2007. Of the energy-use emissions, the emission from mobile source as one of key categories accounted for 19.4% and further the road transport emission occupied the most dominant portion in the category. The road transport emissions can be estimated on the basis of either the fuel consumed (Tier 1) or the distance travelled by the vehicle types and road types (higher Tiers). The latter approach must be suitable for simultaneously estimating $CO_2$, $CH_4$, and $N_2O$ emissions in local administrative districts. The objective of this study was to estimate 31 municipal GHG emissions from road transportation in Gyeonggi Province, Korea. In 2008, the municipalities were consisted of 2,014 towns expressed as Dong and Ri, the smallest administrative district unit. Since mobile sources are moving across other city and province borders, the emission estimated by fuel sold is in fact impossible to ensure consistency between neighbouring cities and provinces. On the other hand, the emission estimated by distance travelled is also impossible to acquire key activity data such as traffic volume, vehicle type and model, and road type in small towns. To solve the problem, we applied a hierarchical cluster analysis to separate town-by-town road patterns (clusters) based on a priori activity information including traffic volume, population, area, and branch road length obtained from small 151 towns. After identifying 10 road patterns, a rule building expert system was developed by visual basic application (VBA) to assort various unknown road patterns into one of 10 known patterns. The expert system was self-verified with original reference information and then objects in each homogeneous pattern were used to regress traffic volume based on the variables of population, area, and branch road length. The program was then applied to assign all the unknown towns into a known pattern and to automatically estimate traffic volumes by regression equations for each town. Further VKT (vehicle kilometer travelled) for each vehicle type in each town was calculated to be mapped by GIS (geological information system) and road transport emission on the corresponding road section was estimated by multiplying emission factors for each vehicle type. Finally all emissions from local branch roads in Gyeonggi Province could be estimated by summing up emissions from 1,902 towns where road information was registered. As a result of the study, the GHG average emission rate by the branch road transport was 6,101 kilotons of $CO_2$ equivalent per year (kt-$CO_2$ Eq/yr) and the total emissions from both main and branch roads was 24,152 kt-$CO_2$ Eq/yr in Gyeonggi Province. The ratio of branch roads emission to the total was 0.28 in 2008.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.152-164
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• 2018

Fermented seasoning pastes were prepared by Aspergillus oryzae and Bacillus subtilis using three edible insects, Tenebrio molitor larvae (TMP), Gryllus bimaculatus (GBP), and Bombyx mori pupa (SPP), with soybean (SBP) as a negative control. Volatile compounds were extracted by the headspace solid-phase microextraction (HS-SPME) method and confirmed by gas chromatograph-mass spectrometry (GC-MS). In total, 121 volatiles from four samples were identified and sub-grouped as 11 esters, 18 alcohols, 23 aldehydes, 5 acids, 10 pyrazines, 2 pyridines, 7 aromatic hydrocarbons, 10 ketones, 19 alkanes, 9 amides, 4 furans and 3 miscellaneous. TMP, GBP, SPP and SBP had 48, 54, 36, and 55 volatile compounds, respectively. Overall, 2,6-dimethylpyrazine and trimethylpyrazine were found by a high proportion in all samples. Tetramethylpyrazine, a main flavor of doenjang, a Korean fermented seasoning soybean paste, was identified as one of the major compounds in TMP, SPP, and SBP. SBP had benzaldehyde, hexanal, n-pentanal, and aldehydes and SPP with pyrazines.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.1
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• pp.15-24
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• 2015

$CH_4$ is a trace gas and one of the key greenhouse gases, which requires continuous and systematic monitoring. The application of eddy covariance technique for $CH_4$ flux measurement requires a fast-response, laser-based spectroscopy. The eddy covariance measurements have been used to monitor $CO_2$ fluxes and their data processing procedures have been standardized and well documented. However, such processes for $CH_4$ fluxes are still lacking. In this note, we report the first measurement of $CH_4$ flux in a rice paddy by employing the eddy covariance technique with a recently commercialized wavelength modulation spectroscopy. $CH_4$ fluxes were measured for five consecutive days before and after the rice transplanting at the Gimje flux monitoring site in 2012. The commercially available $EddyPro^{TM}$ program was used to process these data, following the KoFlux protocol for data-processing. In this process, we quantified and documented the effects of three key corrections: (1) frequency response correction, (2) air density correction, and (3) spectroscopic correction. The effects of these corrections were different between daytime and nighttime, and their magnitudes were greater with larger $CH_4$ fluxes. Overall, the magnitude of $CH_4$ flux increased on average by 20-25% after the corrections. The National Center for AgroMeteorology (www.ncam.kr) will soon release an updated KoFlux program to public users, which includes the spectroscopic correction and the gap-filling of $CH_4$ flux.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.11
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• pp.599-606
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• 2017

The effects of microbubble-oxygen physicochemical method for the removal of organic pollutants, nitrogen, and phosphorus contained in animal manure were investigated using a laboratory scale single reactor. The characteristics of used livestock manure were $36,894{\pm}5,024mg\;TCOD/L$, $22,031{\pm}2,018mg\;SCOD/L$, $4,150{\pm}35mg\;NH_4-N/L$, and $659{\pm}113mg\;PO_4-P/L$. It was confirmed that the amount of organic pollutants, nitrogen, and phosphorus removal was increased by the use of oxygen rather than air as the gas supplied with the microbubble, and by input of larger oxygen amount. When the oxygen was fed with 600 mL flow rate per minute, TCOD and phosphorus removal were 2.5 times and 5.6 times higher than those of air supplied. As the microbubble-oxygen reaction time was longer, the removal rate of nutrients increased gradually. The removal rates of ammonium and phosphorus reach to $41.03{\pm}0.20%$ and $65.49{\pm}1.39%$, respectively, after 24 hours. When the coagulation treatment method was applied to increase phosphorus removal rate from the effluent of microbubble-oxygen treatment, the phosphorus was removed up to 92.7%. However, the removal rate of organic pollutants (TCOD) was as small as $28.7{\pm}0.2%$ within the first 6 hours, and then the negligible removal of TCOD was recorded. This study suggests that microbubble-oxygen can be applied not only livestock manure but also aeration tank of various wastewater treatment plant, which can reduce the load on the associated unit process and produce stable high-quality effluent.

• Journal of Animal Environmental Science
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• v.13 no.3
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• pp.211-218
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• 2007

This study was carried out to develop the technique for manufacturing activated carbon from livestock manure and to analyse it's odor absorptiveness. Each of layer manure(LM), litter from broiler house(BL) and litter from dairy barn(DL), compost from layer manure(LC) and pig manure(PC), and coconut shell(CS) was used as a raw material. Activated carbon by grinding the raw material, adding the coal tar as a binder, palletizing, drying, heating with $N_2$ gas at $400^{\circ}C$ for 1 hour, activating by reaction with steam at a temperature of $750^{\circ}C$ for 1 hour. Moisture contents of raw material was 44.9% in layer compost, 71.9% in layer manure, 24.4% in broiler litter, 47% in pig manure compost and 33.9% in dairy litter. Volatile matter in layer compost, layer manure, broiler litter, pig manure compost and dairy litter was 18.8%, 31.0%, 49.8%, 22.3% and 11.6%, respectively. Surface area(BET) of activated carbon from layer compost, layer manure, broiler litter, pig manure compost, dairy litter and coconut shell was 259.8, 209.8, 63.5, 442.3, 812.9 and $1,040\;m^2/g$, respectively. Activated carbon made by livestock manure or litter were examined with scanning electron microscope, and micropore was a type of sponge like particles honeycombed with chambers. Pore size of activated carbon was ranged from 0.39 to $5.02\;{\AA}$, but coconut shell was $0.30\;{\AA}$. Iodine absorptiveness of activated carbon from livestock manure was $530{\sim}580mg/g$. But activated carbon made by coconut shell was 1000 mg/g. Each activated carbon could absorb odor compound very well. Absorptiveness of activated carbon from layer manure for hydrogen sulfide and trimethyl amino was 74.5% and 73.9% at the accumulated flux of 60,000 ml, but, in the case of ammonia was only 15.2% at the accumulated flux of 10,000 ml

• Korean Journal of Pharmacognosy
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• v.40 no.3
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• pp.196-204
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• 2009

This study was carried out to investigate the in vivo and in vitro inhibitory effect of a traditional herbal complex (HC) extract prepared from a mixture of four oriental herbs (Dioscorea Rhizoma, Glycine soja Sieb. et Zucc, Bombycis corpus, Fermented Glycine soja) that have been widely used for the treatment and prevention of diabetes mellitus on hyperglycemia. The water extract of HC showed potent inhibitory effect on $\alpha$-glucosidase with $IC_{50}$ value of 1.24 mg/mL. Additionally, the ethanol extract of HC was also found to exhibit significant inhibitory effect against protein tyrosine phosphatase $1{\beta}$ ($PTP1{\beta}$), which is known as a major regulator of both insulin and leptin signaling. In the $PTP1{\beta}$ inhibitory assay, the most active n-hexane fraction obtained from the ethanol extract of HC, was identified as a mixture of fatty acid derivatives by gas chromatography-mass spectrometry (GC-MS). In high-fat diet-low dose streptozotocin (STZ)-induced diabetic rat, the water extract of HC improved the oral glucose intolerance as compared with rosiglitazone. HC also caused a marked decrease of body weight and fasting blood glucose and a significant improvement on glucose tolerance in metabolic syndrome mice model. These findings support that this traditional HC may be useful in the control of blood glucose in diabetes mellitus and metabolic syndrome.

• Journal of Life Science
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• v.22 no.8
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• pp.1099-1106
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• 2012

The cytotoxicity of the colorant in conjugated linoleic acid (CLA) was investigated in human cancer cell lines and a normal human cell line. Commercially-available CLA with a brown color (designate crude CLA; c-CLA) was distilled in a vacuum (10 mmHg-$220^{\circ}C$, 10 mmHg-$235^{\circ}C$, 10 mmHg-$240^{\circ}C$, and 20 mmHg-$260^{\circ}C$) for 30 min to obtain pure CLA (distilled CLA; d-CLA) and dark brown-colored CLA (residual CLA; r-CLA) samples. No color intensity was shown in the d-CLA sample obtained under 10 mmHg-$220^{\circ}C$ conditions of distillation when the L (brightness), a (red/blue), and b (yellow/green) parameters were analyzed, whereas the r-CLA sample showed a dark brown color. The composition of CLA isomers in both the d- and r-CLA samples, as compared to that of the c-CLA sample, was not significantly different when analyzed by gas chromatography. When the cytotoxicity of the r-CLA and d-CLA samples obtained under 10 mmHg-$220^{\circ}C$ conditions were compared against human breast cancer cells (MCF-7), human lung cancer cells (A-549), human colon cancer cells (HT-29), human prostate cancer cells (PC-3), and human neuroblastoma cells (SK-N-SH), no significant cytotoxicity was seen in the cell lines. These results suggest that the color or colorant in the CLA samples did not have any effects on the proliferation of human cancer and normal cells and imply that the colorant in commercially available CLA samples is safe for human consumption.

• Tuberculosis and Respiratory Diseases
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• v.67 no.2
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• pp.88-94
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• 2009

Background: From November 2006, The national health insurance system in the Republic of Korea began to cover prescribed long-term oxygen therapy (LTOT) in patients with chronic respiratory insufficiency. This study examined the current status of LTOT after national health insurance coverage. Methods: Between November 1, 2006 and June 30, 2008, the medical records of patients who were prescribed LTOT by chest physicians were reviewed. The data was collected from 13 university hospitals. Results: 197 patients (131 male and 66 female) were prescribed LTOT. The mean age was 64.3${\pm}$13.0 years. The most common underlying disease was chronic obstructive pulmonary disease (n=103, 52.3%). Chest physicians prescribed LTOT using arterial blood gas analysis or a pulse oxymeter (74.6%), symptoms (14%), or a pulmonary function test (11.2%). The mean oxygen flow rate was 1.56${\pm}$0.68 L/min at rest, 2.08${\pm}$0.91 L/min during exercise or 1.51${\pm}$0.75 L/min during sleep. Most patients (98.3%) used oxygen concentrators. Only 19% of patients used ambulatory oxygen supplies. The oxygen saturation before and after LTOT was 83.18${\pm}$10.48% and 91.64${\pm}$7.1%, respectively. After LTOT, dyspnea improved in 81.2% of patients. The mean duration of LTOT was 16.85${\pm}$6.71 hours/day. The rental cost for the oxygen concentrator and related electricity charges were 48,414${\pm}$15,618 won/month and 40,352${\pm}$36,815 won/month, respectively. Approximately 75% of patients had a regular visit by the company. 5.8% of patients had personal pulse oxymetry. 54.9% of patients had their oxygen saturation checked on each visit hospital. 8% of patients were current smokers. The most common complaint with LTOT was the limitation of daily activity (53%). The most common complaint with oxygen concentrators was noise (41%). Conclusion: The patients showed good compliance with LTOT. However, only a few patients used an ambulatory oxygen device or had their oxygen saturation measured.

• Journal of Gastric Cancer
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• v.8 no.1
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• pp.27-34
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• 2008

Purpose: Many recent studies have reported on the feasibility and usefulness of laparoscopy assisted distal gastrectomy (LADG) for treating early gastric cancer. On the other hand, there has been few reports about laparoscopy assisted total gastrectomy (LATG) because upper located gastric cancer is relatively rare and the surgical technique is more difficult than that for LADG, We now present our procedure and results of performing LATG for the gastric cancer located in the upper or middle portion of the stomach. Materials and Methods: From Jan 2005 to Sep 2007, 96 patients underwent LATG by four surgeons at the Asan Medical Center, Seoul, Korea. Among them, 48 consecutive patients who were operated on by asingle surgeon were analyzed with respect to the clinicopathological features, the surgical results and the postoperative courses with using the prospectively collected laparoscopy surgery data. Results: There was no conversion to open surgery during LATG. For all the reconstructions, Roux-en Y esophago-jejunostomy and D1+beta lymphadenectomy were the standard procedures. The mean operation time was $212{\pm}67$ minutes. The mean total number of retrieved lymph nodes was $28.9{\pm}10.54$ (range: $12{\sim}64$) and all the patients had a clear proximal resection margin in their final pathologic reports. The mean time to passing gas, first oral feeding and discharge from the hospital was 2.98, 3.67 and 7.08 days, respectively. There were 5 surgical complications and 2 non-surgical complications for 5 (10.4%) patients, and there was no mortality. None of the patients needed operation because of complications and they recovered with conservative treatments. The mean operation time remained constant after 20 cases and so a learning curve was present. The morbidity rate was not different between the two periods, but the postoperative course was significantly better after the learning curve. Analysis of the factors contributing to the postoperative morbidity, with using logistic regression analysis, showed that the 8MI is the only contributing factor forpostoperative complications (P=0.029, HR=2.513, 95% CI=1.097-5.755). Conclusions: LATG with regional lymph node dissection for upper and middle early gastric cancer is considered to be a safe, feasible method that showed an excellent postoperative course and acceptable morbidity. BMI should be considered in the patient selection at the beginning period because of the impact of the BMI on the postoperative morbidity.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.1
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• pp.56-64
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• 2001

Composting of livestock feces is economic and safe process to decrease the possibility of direct leakage of organic pollutants to ecosystem from commercial and environmental point of view. This study was conducted with three different experiments related to composting of livestock feces. The purpose of experiment 1 was to investigate changes of characteristic of compost pile during composting period by low temperature in cold season. To compare composting effect of experimental compost pile and control pile exposed in cold air, experimental compost piles were warmed up by hot air until their temperatures were reached at $35^{\circ}C$. Sawdust, Ricehull and Ricestraw were mixed with livestock feces as bulking agent. The highest temperatures of compost pile during composting period were in sawdust, rice hull, rice straw, and control were $75^{\circ}C$, $76^{\circ}C$, $68^{\circ}C$, $45^{\circ}C$ respectively. Moisture content, pH, C/N and volume of compost were decreased during composting period. Experiment 2 was carried out to study utilization effect of compost by plant. A corn was cultivated for 3 years on fertilized land with compost and chemical fertilizer. The amount of harvest and nutrition value of corn were analyzed. In first year of trial, the amount of harvest of corn on land treated with compost was lower by 20% than that of land treated with chemical fertilizer. In second year, there was no difference in yield of com between compost and chemical fertilizer. In third year, the yield of com on land fertilized with compost was much more than that of land fertilized with chemical fertilizer. The purpose of experiment 3 was to estimate the decrease of malodorous gas originating from livestock feces by bio-filter. Four types of bio-filters filled with saw dust, night soil, fermented compost and leaf mold were manufactured and tested. Each bio-filter achieved 87-95% $NH_3$ removal efficiency. This performance was maintained for 10 days. The highest $NH_3$ removal efficiency was achieved by leaf mold on the first day of operation period. It reduced the concentration of $NH_3$ by about 95%. Night soil and fermented compost showed nearly equal performance of 93 to 94% for 10 days from the beginning of operation. The concentration of hydrogen sulfide and methyl mercaptan originating for compost were equal to or less than $3mg/{\ell}$ and $2mg/{\ell}$, respectively. After passing throughout the bio-filter, hydrogen sulfide and methyl mercaptan were not detected.