• Journal of Korean Society of Forest Science
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• v.107 no.1
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• pp.71-80
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• 2018

The effect of $SO_2$ treated pads (Sodium metabisulphate 0, 0.5, 1.0, 2.0 g/kg) on the quality of dried persimmons and dried persimmons slices were investigated. The $SO_2$ treated pads did not affect to weight, moisture loss rate, and soluble solid contents of dried persimmons and dried persimmons slices. The color change (${\Delta}E$) of dried persimmons and dried persimmons slices after storage for 8 weeks were the highest (value=6.0, 6.2) in control, whereas that was the lowest (value=4.8, 4.7) under $SO_2$ pad 2.0 g/kg condition, respectively. When we measured the browning degree of dried persimmons, they showed O.D. 0.65, 0.57, 0.29, and 0.18 in serial dilution treated pads with $SO_2$ pad 0, 0.5, 1.0, and 2.0 g/kg. The browning degree data from aforementioned dried persimmons after 8 weeks was similar to that from dried persimmons slices. The decay rate of dried persimmons and dried persimmons slices after storage for 8 weeks were the highest (value=33.3%, 36.7%) in control, whereas that was the lowest (value=3.3%, 6.7%) under $SO_2$ pad 2.0 g/kg condition, respectively. The concentration of residual $SO_2$ in dried persimmons and dried persimmons slices were detected within a safe range of 15.3~30.0 ppm. Therefore, the shelf-life of dried persimmons and dried persimmons slices were lengthened in $SO_2$ treated pads (especially in $SO_2$ pad 2.0 g/kg) for inhibiting of browning and decay.

• Journal of Service Research and Studies
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• v.13 no.1
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• pp.63-75
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• 2023

Due to the development of industry, interest in air pollutants has increased. Air pollutants have affected various fields such as environmental pollution and global warming. Among them, environmental diseases are one of the fields affected by air pollutants. Air pollutants can affect the human body's skin or respiratory tract due to their small molecular size. As a result, various studies on air pollutants and environmental diseases have been conducted. Asthma, part of an environmental disease, can be life-threatening if symptoms worsen and cause asthma attacks, and in the case of adult asthma, it is difficult to cure once it occurs. Factors that worsen asthma include particulate matter and air pollution. Asthma is an increasing prevalence worldwide. In this paper, we study how air pollutants correlate with the number of emergency room admissions in asthma patients and predict the number of future asthma emergency patients using highly correlated air pollutants. Air pollutants used concentrations of five pollutants: sulfur dioxide(SO₂), carbon monoxide(CO), ozone(O₃), nitrogen dioxide(NO₂), and fine dust(PM₁₀), and environmental diseases used data on the number of hospitalizations of asthma patients in the emergency room. Data on the number of emergency patients of air pollutants and asthma were used for a total of 5 years from January 1, 2013 to December 31, 2017. The model made predictions using two models, Informer and LTSF-Linear, and performance indicators of MAE, MAPE, and RMSE were used to measure the performance of the model. The results were compared by making predictions for both cases including and not including the number of emergency patients. This paper presents air pollutants that improve the model's performance in predicting the number of asthma emergency patients using Informer and LTSF-Linear models.

• Korean Journal of Agricultural Science
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• v.5 no.1
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• pp.35-41
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• 1978

Extensive selection works on wild yeasts of fruits were carried cut to obtain strains which are applicable to apple wine making. Among the total number of 1,358 yeast strains which were isolated from various fruit samples collected from the vicinity of Daejeon and other regions cf Korea, the strains SH-49, SH-129 and SH-338 were found to be useful. Then experiments on their morphological and physiological characteristics, and on the aspects of practical use in apple wine making were proceeded. The results obtained were as follows: 1. The strains SH-49 and SH-129, particularly SH-49, were appeared to have good fermentation ability, tolerance to sulfur dioxide and to produce fine quality of apple wine. 2. Apple wines made by using the strain, SH-49 and SH-129 contained less amount of total acids than those by other strains. 3. Apple wines of SH-49 and SH-129 were clarified rapidly during the primary fermentation period, and their absorbancy at 430 nm after 45 days of storage were approximately half of others. 4. Apple wine of SH-338 contained higher amount of residual sugar and its quality was superior to others. It is considered that this strain could be used in the production of apple wine of a characteristic quality. 5. The strains SH-49 and SH-338 were identified as a Saccharomyces cerevisiae according to Taxanomic Study of Yeasts by Lodder, however, classification of SH-129 was suspended for further study.

• Journal of Food Hygiene and Safety
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• v.35 no.3
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• pp.261-270
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• 2020

The application of color retention agents (3 items), preservatives (17 items), and bleaching agents (6 items) as food additives in processed foods were investigated by food type. Among color retention agents, sodium nitrite was used the most with 257 cases, mainly in seasoned jeoktal (71.21%), ready-to-eat foods (7.78%), and breads (4.87%). Of the benzoates (1,236 cases) used as a preservative, sodium benzoate showed up most, in 1,215 cases, while 81.16% of these were in beverages such as beverage base (39.51%), mixed beverages (22.47%), and ginseng/red ginseng beverages (8.89%). Grapefruit seed extracts (3,291 cases) were applied to 44 types of processed foods such as sauces (54.65%), liquid tea (10.46%), and other products (5.15%). Ethyl p-hydroxybenzoate (2,957 cases) was applied to products (total 96.44%) such as sauces (92.15%), blended soy sauce (2.77%), and pickled foods (1.52%). Potassium sorbate was applied to a total of 789 cases, mainly pickled foods (40.43%) and processed fishery products (47.15%). All 27 cases of sorbic acid were applied to fish paste (100%). Of the bleaching agents, sodium bisulfite and sodium hydrosulfite were mainly used in confectioneries, breads or rice cakes, and potassium metabisulfite, sodium metabisulfite, and sulfur dioxide were mainly found in alcoholic beverages including fruit wine, while sodium sulfite was mostly used in pickled foods. These results are deemed useful in applying food additives to processed foods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.11
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• pp.1666-1671
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• 2010

The physicochemical characteristics and acceptability of various commercial low-priced French wines were determined. A~E wines were manufactured from France and F wine was bottled in Germany using French Cabernet Sauvignon grape species. Sample wines were analyzed for pH, total soluble content, acidity, color, total sugar, total polyphenol and sulfur dioxide. The pH of the wines were ranged from 3.3 to 2.6. The total soluble contents were the highest in wine A (10.25 Brix%), followed by wine C (9.72 Brix%), wine D (9.67 Brix%) and wine B (9.61 Brix%) and were the lowest in wines E and F (9.42 Brix%). In the color analysis, wine F showed the highest L (lightness) and a (redness) value (28.11 and 23.86, respectively). The b (yellowness) value for all the samples studied ranged from 52.17 to 61.05. Wine C (62.24 g/L) and F (69.91 g/L) showed higher total sugar contents, and the total sugar contents of wines D, E, B and A were 48.58, 42.74, 37.74 and 36.99 g/L, respectively. Total polyphenol contents were the highest in wine C (2.59 g/L) and the lowest in wines A and B (1.90 g/L). The contents of sulfite in wine D (68.78 mg/L) were the highest and was the lowest in wine B (58.18 mg/L). The sensory characteristics and preference analysis (sourness, bitterness, sweetness, astringent taste, aroma, color and overall acceptability) of the red wines used in this study were determined by 15 panelists using the 7-point hedonic scale. Sourness of wines ranged between 3.8~4.9 and sweetness of wines D and F (3.0) were the highest amongst the red wines used in this study. Wines D, E and F had the higher scores in overall acceptability of sensory properties and wine E was the highest amongst the wines used in this study.

• Journal of Preventive Medicine and Public Health
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• v.32 no.2
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• pp.177-182
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• 1999

Objectives: To reexamine the association between air pollution and daily mortality in Seoul, Korea using a method of meta-analysis with the data filed for 1991 through 1995. Methods: A separate Poisson regression analysis on each district within the metropolitan area of Seoul was conducted to regress daily death counts on levels of each ambient air pollutant, such as total suspended particulates (TSP), sulfur dioxide $(SO_2)$, and ozone $(O_3)$, controlling for variability in the weather condition. We calculated a weighted mean as a meta-analysis summary of the estimates and its standard error. Results: We found that the p value from each pollutant model to test the homogeneity assumption was small (p<0.01) because of the large disparity among district-specific estimates. Therefore, all results reported here were estimated from the random effect model. Using the weighted mean that we calculated, the mortality at a $100{\mu}g/m^3$ increment in a 3-day moving average of TSP levels was 1.034 (95% Cl 1.009-1.059). The mortality was estimated to increase 6% (95% Cl 3-10%) and 3% (95% Cl 0-6%) with each 50 ppb increase for 9-day moving average of SO2 and 1-hr maximum O3, respectively. Conclusions: Like most of air pollution epidemiologic studies, this meta-analysis cannot avoid fleeing from measurement misclassification since no personal measurement was taken. However, we can expect that a measurement bias be reduced in a district-specific estimate since a monitoring station is hefter representative cf air quality of the matched district. The similar results to those from the previous studios indicated existence of health effect of air pollution at current levels in many industrialized countries, including Korea.

• Resources Recycling
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• v.23 no.2
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• pp.17-25
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• 2014

The thermal effect on the compositional change of the $SO_2$ absorption process product was investigated compared with the composition of raw material when dolomite is employed in place of lime in the scrubbing process based on thermodynamic estimation. It was considered that the equilibrium reactions which directly related with the formation of $CaSO_4$ and $MgSO_4$, the absorption process products, are those between $Ca^{2+}$ and $Ca(OH)_2$, $Mg^{2+}$ and $Mg(OH)_2$, and the secondary dissociation reaction of $H_2SO_4$. It was thought to be necessary to examine the enthalpy change for the formation reactions of $CaSO_4$ and $MgSO_4$ along with the thermal feature of the relative reactions to figure out the influence of temperature on the compositional change of absorption process products. The stable regions for $Ca(OH)_2$ and $Mg(OH)_2$ in Pourbaix diagram were found to be increased as temperature rises and the equilibrium reaction between $Ca^{2+}$ and $Ca(OH)_2$ was investigated to be more strongly influence by temperature change compared with the equilibrium reaction between $Mg^{2+}$ and $Mg(OH)_2$. The amounts of $CaSO_4$ and $MgSO_4$ were anticipated to be decreased with temperature considering the thermal characteristics for the equilibrium reactions regarding calcium, magnesium, and $H_2SO_4$. It was understood that the formation ratio between $CaSO_4$ and $MgSO_4$ is greater than the composition ratio between calcium and magnesium contained in dolomite at specific temperature and the decrease of the formation ratio of $CaSO_4$ and $MgSO_4$ with temperature was estimated to be diminished as the content of calcium in dolomite is increased. In addition, the extent of the change in the compositional ratio between absorption process products was examined to be reduced compared with the composition of raw material as the calcium content in dolomite is raised.

• Korean Journal of Remote Sensing
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• v.32 no.6
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• pp.629-637
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• 2016

In this present study, we identified the $SO_2$ effect on $O_3$ retrieval from the Ozone Monitoring Instrument (OMI) measurement over Chinese Industrial region from 2005 through 2007. The Planetary boundary layer (PBL) $SO_2$ data measured by OMI sensor is used in this present study. OMI-Total Ozone Mapping Spectrometer (TOMS) total $O_3$ is compared with OMI-Differential Optical Absorption Spectrometer (DOAS) total $O_3$ in various $SO_2$ condition in PBL. The difference between OMI-TOMS and OMI-DOAS total $O_3$ (T-D) shows dependency on $SO_2$ (R (Correlation coefficient) = 0.36). Since aerosol has been reported to cause uncertainty of both OMI-TOMS and OMI-DOAS total $O_3$ retrieval, the aerosol effect on relationship between PBL $SO_2$ and T-D is investigated with changing Aerosol Optical Depth (AOD). There is negligible aerosol effect on the relationship showing similar slope ($1.83{\leq}slope{\leq}2.36$) between PBL $SO_2$ and T-D in various AOD conditions. We also found that the rate of change in T-D per 1.0 DU change in PBL, middle troposphere (TRM), and upper troposphere and stratosphere (STL) are 1.6 DU, 3.9 DU and 4.9 DU, respectively. It shows that the altitude where $SO_2$ exist can affect the value of T-D, which could be due to reduced absolute radiance sensitivity in the boundary layer at 317.5 nm which is used to retrieve OMI-TOMS ozone in boundary layer.

• Korean Journal of Remote Sensing
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• v.36 no.5_3
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• pp.1053-1066
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• 2020

Sulfur dioxide (SO₂) is primarily released through industrial, residential, and transportation activities, and creates secondary air pollutants through chemical reactions in the atmosphere. Long-term exposure to SO₂ can result in a negative effect on the human body causing respiratory or cardiovascular disease, which makes the effective and continuous monitoring of SO₂ crucial. In South Korea, SO₂ monitoring at ground stations has been performed, but this does not provide spatially continuous information of SO₂ concentrations. Thus, this research estimated spatially continuous ground-level SO₂ concentrations at 1 km resolution over South Korea through the synergistic use of satellite data and numerical models. A stacking ensemble approach, fusing multiple machine learning algorithms at two levels (i.e., base and meta), was adopted for ground-level SO₂ estimation using data from January 2015 to April 2019. Random forest and extreme gradient boosting were used as based models and multiple linear regression was adopted for the meta-model. The cross-validation results showed that the meta-model produced the improved performance by 25% compared to the base models, resulting in the correlation coefficient of 0.48 and root-mean-square-error of 0.0032 ppm. In addition, the temporal transferability of the approach was evaluated for one-year data which were not used in the model development. The spatial distribution of ground-level SO₂ concentrations based on the proposed model agreed with the general seasonality of SO₂ and the temporal patterns of emission sources.

• Tuberculosis and Respiratory Diseases
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• v.55 no.6
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• pp.560-569
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• 2003

Background : A large number of pollutants such as sulfur dioxide, nitric oxide, carbon monoxide, particulate matter, and ozone influence on the body. These pollutants put a burden on the lung and the sequelae resulting from the oxidative stress are thought to contribute to the development of fibrotic lung disease, emphysema, chronic bronchitis and lung cancer. Also, carbon monoxide generated from the incomplete combustion of carbon-containing compounds is an important component of air pollution caused by traffic exhaust fumes and has the toxic effect of tissue hypoxia and produce various systemic and neurologic complications. The objective of this study is to compare the difference of pulmonary function and serum carboxyhemoglobin(CO-Hb) level between the traffic policemen and clerk policemen. Method : Three hundred and twenty-nine of traffic policemen, and one hundred and thirty clerk policemen were included between 2001 May and 2002 August. The policemen who took part in this study were asked to fill out a questionnaire which included questions on age, smoking, drinking, years of working, work-related symptoms and past medical history. The serum CO-Hb level was measured by using carboxyoximeter. Pulmonary function test was done by using automated spirometer. Additional tests, such as elecrocardiogram, urinalysis, chest radiography, blood chemistry, and CBC, were also done. Results : $FEV_1(%)$ was $97.1{\pm}0.85%$, and $105.7{\pm}1.21%$(p<0.05). FVC(%) was $94.6{\pm}0.67%$, and $102.1{\pm}1.09%$, respectively(p<0.05). Serum CO-Hb level was $2.4{\pm}0.06%$, and $1.8{\pm}0.08%$(p<0.05). After correction of confounding factors (age, smoking), significant variables were FVC(%), $FEV_1(%)$ and serum CO-Hb level(%)(p<0.05). Conclusion : Long exposure to air pollution may influence the pulmonary function and serum CO-Hb level. But, further prospective cohort study will be needed to elucidate detailed influences of specific pollutants on pulmonary function and serum carboxyhemoglobin level.