• Culinary science and hospitality research
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• v.22 no.8
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• pp.149-156
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• 2016

The purpose of this study is to reduce the contaminants (total volatile organic compounds (TVOCs), fine particle, odor and total airborne bacteria) during cooking process in cooking chamber, and to decrease the health damage in indoor space that has bad work environment. In order to solve the shortcomings of existing air purifiers and remove all kinds of pollutants effectively, this study focused on the development of indoor air purifiers which are made of bar type. Bio-ceramics filter which combines activated carbon and loess. The air cleaners developed with 4 measuring items including TVOCs, particulate matter, complex odor and total airborne bacteria were measured comparing their pre-service test to their post-service test after a period of time. The measured results showed higher removal efficiency of 91.02% as the concentration of TVOCs was reduced from $2,500{\mu}g/m^3$ to $223{\mu}g/m^3$. Second, the particulate matter removal ratio was 97.51% efficient with average concentration of $26.68{\mu}g/m^3$. Third, the odor showed 95.20% reduction as air dilution ratio averaged out at 144. Last, total airborne bacteria was eliminated by over 94% showing the changeable concentration from $787{\sim}814CFU/m^3$ to $47{\sim}40CFU/m^3$. In addition, the removal rate of harmful pollutants is excellent, and it is expected that the environment of the existing poor cooking room will be greatly improved by using the developed air purifier in combination with the ventilation device and the stove hood.

• Journal of Environmental Health Sciences
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• v.46 no.1
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• pp.35-44
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• 2020

Objectives: The purpose of this study was to compare the health status of residents who were exposed to the Iksan industrial area in the living environment and those who were not exposed to such a source of industrial activity through a questionnaire survey designed to appraise the residents' health levels. Method: The authors conducted a health questionnaire survey of 1,012 residents around Iksan regarding their personal information, physician-diagnosed disease history, odors experienced, and more. Logistic regression was performed to identify the associations between hazardous chemical exposure and physician-diagnosed diseases. Result: Logistic regression shows significant differences in allergic rhinitis, cardiovascular disease, hypertension, dyslipidemia, liver disease, and osteoporosis. Odors were experienced by 88.0% of the survey group. The seasons were summer (71%) and spring (24.9%). Conclusion: For allergic rhinitis, cerebral cardiovascular disease, and hypertension, which were significantly higher in the case group than in the control group in the disease diagnosis and disease treatment history of physicians, it was difficult to completely eliminate the association with odor exposure in the Iksan Industrial Complex. It is considered that it has affected nearby residents. This study means that a correlation between chronic diseases has been found through regression analysis, and furthermore, this result can be used as a basis for sampling for secondary epidemiological surveys.

• Fire Science and Engineering
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• v.31 no.6
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• pp.107-111
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• 2017

The purpose of this study was to develop a Eco smoking booth that can effectively reduce hazardous pollutants generated during smoking and evaluate the efficiency and effectiveness of removing hazardous pollutants. The design and manufacture of an eco-friendly automatic smoking booth equipped with deodorizing facilities, such as inlet - HEPA filter - electrostatic precipitator (EP) - impregnated activated carbon - exhaust port, etc., and the efficiency of removing hazardous pollutants from inside and outside was measured and evaluated. The complex odor removal efficiency was 95.37% inside the smoking booth, and 97.38% at the exit of the preventive facility. The carbon monoxide removal efficiency was 94.25% in the inside and 98.32% in the outlet. In addition, the removal efficiency of particulate matter, (PM1, PM2.5, and PM10) inside the smoking booth was 98.59%, and 98.85% at the outlet. The total volatile organic compounds (TVOCs) decreased from $26,000{\mu}g/m^3$ to $5,203{\mu}g/m^3$ in the smoking booth, resulting in 79.99% removal efficiency. After the ventilator was operated, the measured effluent concentration was $5,019{\mu}g/m^3$, and the removal efficiency was 80.70%. Therefore, the smoking booth designed and manufactured through this study can be applied to the removal of harmful pollutants even in the small working environment in the future.

• Journal of Wetlands Research
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• v.10 no.2
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• pp.129-141
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• 2008

This study analyzed and assessed the water quality of a small urban stream in the apartment complex of Yewol-Dong, Buchun-Si at Korea. The flows in the stream due to the interceptions of sewage and normal flow are usually low and the water quality and offensive odor problems by inflows of the sewage and other pollutants are occurred in the study area. Therefore we intended to monitor and identify the water quality conditions. Based on this, we simulated water quality using QUAL2E model and investigated water quality characteristics for the future. As the results, we found that the water quality depended on the inflows of point and non-point sources and so it is important to maintain instream flow for improvement of water quality problem and to intercept point and non-point sources in this study area.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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• pp.650-655
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• 2017

Extraction methods for cultured sea mussels Mytilus edulis and the quality characteristics of resulting extracts were investigated. The crude protein, carbohydrate and volatile basic nitrogen content of raw sea mussels was 15.2%, 1.9%, and 11.2 mg/100 g, respectively. Extracts were prepared using three different methods: hot-water extract (WE), scrap enzymatic hydrolysate extraction (SE), and complex extraction (CE). The respective extracts contained 5.5%, 8.6%, and 6.6% crude protein; 281.7, 366.0, and 343.0 mg/100 g amino nitrogen,: and 2.0%, 1.1% and 1.8% salinity. Their extraction yields were 689, 323, and 1,012 mL/kg. The CE method was superior to the traditional WE method in terms of extraction yield, amino-nitrogen content, and organoleptic qualities, but not odor. Active taste components were evaluated and the total free amino acid content of the WE and CE methods was 5,667.0 and 7,006.3 mg/100 g, respectively. The concentrations of major components (for WE and CE methods, respectively) were as follows: glutamic acid (1,244.0 and 955.4 mg/100 g), taurine (987.9 and 746.8 mg/100 g), glycine (721.2 and 847.0 mg/100 g), alanine (341.9 and 423.8 mg/100 g), arginine (265.5 and 376.5 mg/100 g), lysine (199.8 and 270.4 mg/100 g), and proline (253.9 and 220.3 mg/100 g). In conclusion, these results demonstrate that there is potential for using the CE method to expand the commercial utilization of sea mussels as a flavoring substance resource.

• Journal of Microbiology and Biotechnology
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• v.27 no.12
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• pp.2199-2210
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• 2017

Soil burial is the most widely used disposal method for infected pig carcasses, but composting has gained attention as an alternative disposal method because pig carcasses can be decomposed rapidly and safely by composting. To understand the pig carcass decomposition process in soil burial and by composting, pilot-scale test systems that simulated soil burial and composting were designed and constructed in the field. The envelope material samples were collected using special sampling devices without disturbance, and bacterial community dynamics were analyzed by high-throughput pyrosequencing for 340 days. Based on the odor gas intensity profiles, it was estimated that the active and advanced decay stages were reached earlier by composting than by soil burial. The dominant bacterial communities in the soil were aerobic and/or facultatively anaerobic gram-negative bacteria such as Pseudomonas, Gelidibacter, Mucilaginibacter, and Brevundimonas. However, the dominant bacteria in the composting system were anaerobic, thermophilic, endospore-forming, and/or halophilic gram-positive bacteria such as Pelotomaculum, Lentibacillus, Clostridium, and Caldicoprobacter. Different dominant bacteria played important roles in the decomposition of pig carcasses in the soil and compost. This study provides useful comparative date for the degradation of pig carcasses in the soil burial and composting systems.

• Journal of Environmental Science International
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• v.18 no.7
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• pp.709-714
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• 2009

Catalytic activities of $V_2O_5/TiO_2$ catalyst were investigated under reaction conditions such as reaction temperature, catalyst size, inlet concentration and space velocity. A 1,2-dichlorobenzene(1,2-DCB) concentrations were measured in front and after of the heated $V_2O_5/TiO_2$ catalyst bed, and conversion efficiency of 1,2-DCB was determined from it's concentration difference. The conversion of 1,2-DCB using a pellet type catalyst in the bench-scale reactor was lower than that with the powder type used in the micro flow-scale reactor. However, when the pellet size was halved, the conversion was similar to that with the powder type catalyst. The highest conversion was shown with an inlet concentration of 100 ppmv, but when the concentration was higher or lower than 100 ppmv, the conversion was found to decrease. Complete conversion was obtained when the GHSV was maintained at below 10,000 $h^{-1}$, even at the relatively low temperature of $250^{\circ}C$. Water vapor inhibited the conversion of 1,2-DCB, which was suspected to be due to the competitive adsorption between the reactant and water for active sites.

• Journal of Korean Society on Water Environment
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• v.25 no.4
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• pp.597-605
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• 2009

Algae bloom occurred in reservoir in summer can cause taste and odor in water and disturb the flocculation and sedimentation processes in water treatment plant and cause sand filter plugging. It was also reported that microcystins, anatoxin and saxitoxin released from cyanobacteria had acute toxic effects on liver and nervous system. For these reasons, many advanced countries inclusive of WHO set the guideline for these toxins and cyanotoxins have been managed with regular monitoring in Korea as well. However, complex sample preparation steps such as a solid phase extraction (SPE) and derivatization are required with an existing analysis method with HPLC. We needed to improve an analysis method for low extraction efficiency and long sample preparation time. In this study, we have established a new LC/MS/MS method which can simultaneously determine 6 cyanotoxins (Microcystins-LR, Microcystins-RR, Microcystins-YR, Anatoxin-a, Saxitoxin, Neosaxitoxin) with only simple filtration step. When $75{\mu}L$ filterated sample was injected onto the LC-MS/MS, the recovery ranged from 86% to 112% and the MDL was $0.025{\sim}0.581{\mu}g/L$. We can make the MDL be lower than the guideline ($1{\sim}3{\mu}g/L$) of advanced countries with simple preparation.

• Journal of Korean society of Dental Hygiene
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• v.22 no.2
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• pp.125-132
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• 2022

Objectives: The purpose of this study was to examine the relationship between stress and halitosis in a representative sample of Korean adolescents. Methods: This study was based on the 15th Korea Youth Risk Behavior Survey (2019). The final participation rate in the survey was 95.3%; 57,303 out of 60,100 (95.3%) adolescents aged 13-18 years were selected. Multiple logistic regression with complex samples was performed to identify the correlation between stress and halitosis. Stress level was classified as 'very much', 'a little', and 'not much' and halitosis was defined as the presence of an unpleasant odor in the oral cavity. Results: The prevalence of halitosis among students was 21.3%. As a result of multiple regression analysis, the 'a little' [odds ratio (OR); 1.39, 95% confidence interval (CI); 1.29-1.49] and 'very much' stress group (OR; 1.78, 95% CI; 1.66-1.90) exhibited significantly higher risk of halitosis than the 'not much' stress group. Conclusions: A significant correlation between stress and halitosis exists among Korean adolescents. Therefore, psychological factors such as stress should be considered in managing halitosis in adolescents.

• Korean Journal of Environmental Agriculture
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• v.19 no.1
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• pp.44-50
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• 2000

This study was carried out to get the basic data on the efficient processing method of food wastes for utilizing as the resources of swine feeds composition, mineral and toxic elements of food waste were estimated in relation to the steps of processing and fermentation with MS (Miraculous soil-bacteria) microorganism complex. The chemical composition of food wastes was largely varied according to disposing sites, collection time and season. Offensive odor was reduced by anaerobic fermentation with MS microorganism complex. Food wastes fermented with MS microorganism complex have high contents in crude protein (24.1% D.M) and crude fat (12.9% D.M). Mineral composition was to be relatively well balanced compared to other plant or animal feed resources. Particularly the content of sodium was slightly higher than that of grains or agricultural byproducts. In food wastes fermented with MS microorganism complex, heavy metals such as Hg, As or F were not detected. Pb or Cd were detected in small quantities but their levels were below the dose s-permitted feeding standard of permitted dose in feeding standard. These results indicated that food wastes could be efficiently used for the resources of swine feeds through proper processing and fermentation.