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A Study on the Environmental Characteristics of a Two-storey Pig House for the Control of Manure (고상식돈사의 분뇨처리에 관한 연구)

  • Jeong, J.W.;Yoo, Y.H.;Park, K.H.;Kam, D.H.;Lee, M.J.
    • Journal of Animal Environmental Science
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    • v.14 no.3
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    • pp.175-182
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    • 2008
  • This research was conducted to examine proper manure treatment methods for a high-rise swine barn with results of the fact-finding survey on manure treatment methods used in high-rise swine barns and sawdust swine barns In Korea. The average temperatures on bedding of control, T1, and T2 were between $25.3{\sim}25.4^{\circ}C$ with little difference. Air flow rate of T2 was slower than those of control and T1. Dust generation in control was 54 cpm which was higher than T1 and T2. The average ammonia concentration in control was highest showing 6.0 ppm, ranged from 0.5 to 14.5 ppm, with statistical difference (p<0.05), compared to T1 (2.8 ppm) and T2 (2.6 ppm). Sawdust spreading used in control and T1 decreased ammonia concentration. T1 showed the lowest concentration of $CO_2$. Water contents of control and T2 were close to the proper water content, 65%. T1 had the highest water content and pH, and the lowest organic matter and C/N ratio. The volumes of sawdust spread per head were 0.26 and $0.27m^3$ in control and T2, respectively, which was less than T1. Operating cost such as an electricity bill for blowers was cheap in T2. Hence, T2 bedding sawdust up to 10 cm thick and periodically spreading additional sawdust from second story was recommended.

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Empirical Estimation and Diurnal Patterns of Surface PM2.5 Concentration in Seoul Using GOCI AOD (GOCI AOD를 이용한 서울 지역 지상 PM2.5 농도의 경험적 추정 및 일 변동성 분석)

  • Kim, Sang-Min;Yoon, Jongmin;Moon, Kyung-Jung;Kim, Deok-Rae;Koo, Ja-Ho;Choi, Myungje;Kim, Kwang Nyun;Lee, Yun Gon
    • Korean Journal of Remote Sensing
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    • v.34 no.3
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    • pp.451-463
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    • 2018
  • The empirical/statistical models to estimate the ground Particulate Matter ($PM_{2.5}$) concentration from Geostationary Ocean Color Imager (GOCI) Aerosol Optical Depth (AOD) product were developed and analyzed for the period of 2015 in Seoul, South Korea. In the model construction of AOD-$PM_{2.5}$, two vertical correction methods using the planetary boundary layer height and the vertical ratio of aerosol, and humidity correction method using the hygroscopic growth factor were applied to respective models. The vertical correction for AOD and humidity correction for $PM_{2.5}$ concentration played an important role in improving accuracy of overall estimation. The multiple linear regression (MLR) models with additional meteorological factors (wind speed, visibility, and air temperature) affecting AOD and $PM_{2.5}$ relationships were constructed for the whole year and each season. As a result, determination coefficients of MLR models were significantly increased, compared to those of empirical models. In this study, we analyzed the seasonal, monthly and diurnal characteristics of AOD-$PM_{2.5}$model. when the MLR model is seasonally constructed, underestimation tendency in high $PM_{2.5}$ cases for the whole year were improved. The monthly and diurnal patterns of observed $PM_{2.5}$ and estimated $PM_{2.5}$ were similar. The results of this study, which estimates surface $PM_{2.5}$ concentration using geostationary satellite AOD, are expected to be applicable to the future GK-2A and GK-2B.

A Study on the Characteristics of Condensable Fine Particles in Flue Gas (배출가스 중 응축성미세먼지 특성 연구)

  • Gong, Buju;Kim, Jonghyeon;Kim, Hyeri;Lee, Sangbo;Kim, Hyungchun;Jo, Jeonghwa;Kim, Jeonghun;Gang, Daeil;Park, Jeong Min;Hong, Jihyung
    • Journal of Korean Society for Atmospheric Environment
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    • v.32 no.5
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    • pp.501-512
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    • 2016
  • The study evaluated methods to measure condensable fine particles in flue gases and measured particulate matter by fuel and material to get precise concentrations and quantities. As a result of the method evaluation, it is required to improve test methods for measuring Condensable Particulate Matter (CPM) emitted after the conventional Filterable Particulate Matter (FPM) measurement process. Relative Standard Deviation (RSD) based on the evaluated analysis process showed that RSD percentages of FPM and CPM were around 27.0~139.5%. As errors in the process of CPM measurement and analysis can be caused while separating and dehydrating organic and inorganic materials from condensed liquid samples, transporting samples, and titrating ammonium hydroxide in the sample, it is required to comply with the exact test procedures. As for characteristics of FPM and CPM concentrations, CPM had about 1.6~63 times higher concentrations than FPM, and CPM caused huge increase in PM mass concentrations. Also, emission concentrations and quantities varied according to the characteristics of each fuel, the size of emitting facilities, operational conditions of emitters, etc. PM in the flue gases mostly consisted of CPM (61~99%), and the result of organic/inorganic component analysis revealed that organic dusts accounted for 30~88%. High-efficiency prevention facilities also had high concentrations of CPM due to large amounts of $NO_x$, and the more fuels, the more inorganic dusts. As a result of comparison between emission coefficients by fuel and the EPA AP-42, FPM had lower result values compared to that in the US materials, and CPM had higher values than FPM. For the emission coefficients of the total PM (FPM+CPM) by industry, that of thermal power stations (bituminous coal) was 71.64 g/ton, and cement manufacturing facility (blended fuels) 18.90 g/ton. In order to estimate emission quantities and coefficients proper to the circumstances of air pollutant-emitting facilities in Korea, measurement data need to be calculated in stages by facility condition according to the CPM measurement method in the study. About 80% of PM in flue gases are CPM, and a half of which are organic dusts that are mostly unknown yet. For effective management and control of PM in flue gases, it is necessary to identify the current conditions through quantitative and qualitative analysis of harmful organic substances, and have more interest in and conduct studies on unknown materials' measurements and behaviors.

A Study on the Characteristics of Oil-water Separation in Non-point Source Control Facility by Coalescence Mechanism of Spiral Buoyant Media (나선형 부유 고분자 여재의 Coalescence 특성을 이용한 비점오염원 저감시설의 유수분리특성 연구)

  • Kang, Sung-Won;Kim, Seog-Ku;Kim, Young-Im;Yun, Sang-Leen;Kim, Soo-Hae;Kim, Mee-Kyung
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.8
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    • pp.950-955
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    • 2007
  • Non-point source control system which had been designed only for oil-water separation in the fields of oil refinery and garage was upgraded in this research for the removal of runoff pollutants in impervious urban area. Pollutants including oil from driveway and bridge were eliminated by two types of pathway in the system. One is the coalescence mechanism that the oil droplets in the runoff come into contact with each other in the spiral buoyant media surface and form larger coalesced droplets of oil that are carried upstream to the oil layer. The other is the precipitation that solids in runoff were settled by gravity in the system. In this research, coalescing characteristics of oil and water separation were investigated through image analyses, and efficiencies of the non-point source control system were evaluated using dust in driveway and waste engine oil. Media made of high density and high molecular weight polyethylene was indeterminate helical shape and had sleek surface by analysing SEM photographs and BET. Surface area and specific gravity of media which were measured directly were 1,428 $mm^2$ and 45.3 $kg/m^3$ respectively. From the image analyses of the oil droplets photographs which were taken by using microscope, it was proved clearly that the coalescence was the main pathway in the removal of oil from the runoff. Finally, the performances of the non-point source control system filled up with the media were suspended solid $86.6\sim95.2%$, $COD_{Cr}$, $87.3\sim95.4%$, n-Hexane extractable materials $71.8\sim94.8%$ respectively.

Identification of the Environmentally Problematic Input/Environmental Emissions and Selection of the Optimum End-of-pipe Treatment Technologies of the Cement Manufacturing Process (시멘트 제조공정의 환경적 취약 투입물/환경오염물 파악 및 최적종말처리 공정 선정)

  • Lee, Joo-Young;Kim, Yoon-Ha;Lee, Kun-Mo
    • Journal of Korean Society of Environmental Engineers
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    • v.39 no.8
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    • pp.449-455
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    • 2017
  • Process input data including material and energy, process output data including product, co-product and its environmental emissions of the reference and target processes were collected and analyzed to evaluate the process performance. Environmentally problematic input/environmental emissions of the manufacturing processes were identified using these data. Significant process inputs contributing to each of the environmental emissions were identified using multiple regression analysis between the process inputs and environmental emissions. Optimum combination of the end-of-pipe technologies for treating the environmental emissions considering economic aspects was made using the linear programming technique. The cement manufacturing processes in Korea and the EU producing same type of cement were chosen for the case study. Environmentally problematic input/environmental emissions of the domestic cement manufacturing processes include coal, dust, and $SO_x$. Multiple regression analysis among the process inputs and environmental emissions revealed that $CO_2$ emission was influenced most by coal, followed by the input raw materials and gypsum. $SO_x$ emission was influenced by coal, and dust emission by gypsum followed by raw material. Optimization of the end-of-pipe technologies treating dust showed that a combination of 100% of the electro precipitator and 2.4% of the fiber filter gives the lowest cost. The $SO_x$ case showed that a combination of 100% of the dry addition process and 25.88% of the wet scrubber gives the lowest cost. Salient feature of this research is that it proposed a method for identifying environmentally problematic input/environmental emissions of the manufacturing processes, in particular, cement manufacturing process. Another feature is that it showed a method for selecting the optimum combination of the end-of-pipe treatment technologies.

The Influence of Office Indoor Air Qualitys on the Dry Eye Symptom of Contact Lens Wearers (사무실 실내공기질과 콘택트렌즈 착용여부가 안구 건조증에 미치는 영향)

  • Kim, Dea Jong;Park, Moon Chan;Lee, Se Hoon;Kim, Hyun Uk;Lee, Wha Ja;Cha, Jung Won
    • Journal of Korean Ophthalmic Optics Society
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    • v.17 no.2
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    • pp.215-222
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    • 2012
  • Purpose: This study was performed to investigate the influence of indoor air qualities of an office environment on dry eye syndrome for wearing contact lens and non-wearing contact lens. Methods: To study the effects of indoor air qualities on dry eye syndrome for seventy-one subjects, $CO_2$, temperature, humidity, TSP, PM10, HCHO were measured. Each subject was tested by a McMonnie's dry eye syndrome questionnaire, a Schirmer Tear Test-I (S.T.T-I), a Schirmer Tear Test-II with anesthetics (S.T.T-II), and Tear film break-up time (T.B.U.T) in the their offices. Results: There was significant relation between the indoor air quality and dry eye syndrome for wearing contact lens and non-wearing when TSP was over $200{\mu}g/m^3$, PM10 was higher than $86.7{\mu}g/m^3$ and Formaldehyde was over $0.4{\sim}1.0{\mu}g/m^3$. However, there was no significant effect on dry eye syndrome with $CO_2$ (p=.0146), temperature (p=0.074) and humidity (p=0.053). Conclusions: It was indicated that $CO_2$, temperature and humidity were no effect on dry eye syndrome in the office environment. However TSP, PM10, formaldehyde, and wearing contact lens were effect on dry eye syndrome. Therefore, the entire management of wearing contact lens and the individual evaluation of the indoor air quality are required.

Clinical Findings of Mycoplasma Pneumonia in Children, from 1998 to 2003 (최근 6년간(1998-2003) 소아 Mycoplasma 폐렴의 임상 양상)

  • Kim, Ji-Hyun;Chae, Soo Ahn;Lee, Dong-Keun
    • Clinical and Experimental Pediatrics
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    • v.48 no.9
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    • pp.969-975
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    • 2005
  • Purpose : We performed a study of clinical findings of Mycoplasma Pneumonia in children, to know differences between recent clinical manifestations of Mycoplasma pneumonia and previous studies. Methods : The subjects of this study were 393 children who were diagnosed as Mycoplasma pneumonia with high titers of Mycoplasma antibody(${\geq}1$ : 160) or fourfold rises of Mycoplasma antibody at Chung Ang University Hospital from January 1998 to December 2003. We practiced a retrospective study on the clinical manifestations of Mycoplasma pneumonia based on their medical records. Results : Male to female ratio was 1.06 to 1 and mean age was $4.32{\pm}2.94years$. The highest incidence was in the age of 2 to 3 years(18.6 percent). Most frequent months were October, and November in 2000, April in 2002, and October and, December in 2003. Twenty six point seven percent showed allergic diseases. Second degree relatives of 10.7 percent patients had allergic diseases. Forty three point three percent were admitted before this admission for pneumonia. Allergic tests were positive in 65.7 percent. Cough, and sputum were the most common symptoms and abdominal pain, and vomiting were the most frequent extrapulmonary symptoms. Atelectasis and pleural effusion were seen in 2.5 percent and 1.8 percent. Infiltrations were more common on the right side. Titers of each simultaneous test for cold agglutinin and mycoplasma antibody were not in proportion to each other (P=0.163). Conclusion : The onset age of mycoplasma pneumonia was found to be lower than it used to be. More patients had a past medical history or a family history of allergic disease, and more wheezing was heard and associated with recurrent pneumonia.

Long-term Trends of the Concentrations of Mass and Chemical Composition in PM2.5 over Seoul (서울시 대기 중 초미세먼지 (PM2.5) 질량과 화학성분 농도의 장기 변동 추이)

  • Han, Sang Hee;Kim, Yong Pyo
    • Journal of Korean Society for Atmospheric Environment
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    • v.31 no.2
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    • pp.143-156
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    • 2015
  • The literature data of the mass concentrations of TSP, $PM_{10}$, and $PM_{2.5}$, and chemical composition of $PM_{2.5}$ (sulfate, nitrate, ammonium, OC, and EC) from 1985 and 2013 at Seoul were collected and the temporal trends were discussed in relation with the policy directions. Generally, the mass concentrations of TSP, $PM_{10}$, and $PM_{2.5}$ at Seoul have showed decreasing trends. However, it is not clear what might be the major reason(s) for the trends. The concentrations of ionic component in $PM_{2.5}$ showed different trends, sulfate being reduced during the 1990s but no trend during the 2000s. The concentrations of nitrate and ammonium were increasing during the 2000s. The concentrations of OC show no apparent trend while that of EC decreased. Further policy directions are suggested based on the temporal trends of the chemical composition in $PM_{2.5}$.

PM2.5 Simulations for the Seoul Metropolitan Area: (II) Estimation of Self-Contributions and Emission-to-PM2.5 Conversion Rates for Each Source Category (수도권 초미세먼지 농도모사 : (II) 오염원별, 배출물질별 자체 기여도 및 전환율 산정)

  • Kim, Soontae;Bae, Changhan;Yoo, Chul;Kim, Byeong-Uk;Kim, Hyun Cheol;Moon, Nankyoung
    • Journal of Korean Society for Atmospheric Environment
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    • v.33 no.4
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    • pp.377-392
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    • 2017
  • A set of BFM (Brute Force Method) simulations with the CMAQ (Community Multiscale Air Quality) model were conducted in order to estimate self-contributions and conversion rates of PPM (Primary $PM_{2.5}$), $NO_x$, $SO_2$, $NH_3$, and VOC emissions to $PM_{2.5}$ concentrations over the SMA (Seoul Metropolitan Area). CAPSS (Clean Air Policy Support System) 2013 EI (emissions inventory) from the NIER (National Institute of Environmental Research) was used for the base and sensitivity simulations. SCCs (Source Classification Codes) in the EI were utilized to group the emissions into area, mobile, and point source categories. PPM and $PM_{2.5}$ precursor emissions from each source category were reduced by 50%. In turn, air quality was simulated with CMAQ during January, April, July, and October in 2014 for the BFM runs. In this study, seasonal variations of SMA $PM_{2.5}$ self-sensitivities to PPM, $SO_2$, and $NH_3$ emissions can be observed even when the seasonal emission rates are almost identical. For example, when the mobile PPM emissions from the SMA were 634 TPM (Tons Per Month) and 603 TPM in January and July, self-contributions of the emissions to monthly mean $PM_{2.5}$ were $2.7{\mu}g/m^3$ and $1.3{\mu}g/m^3$ for the months, respectively. Similarly, while $NH_3$ emissions from area sources were 4,169 TPM and 3,951 TPM in January and July, the self-contributions to monthly mean $PM_{2.5}$ for the months were $2.0{\mu}g/m^3$ and $4.4{\mu}g/m^3$, respectively. Meanwhile, emission-to-$PM_{2.5}$ conversion rates of precursors vary among source categories. For instance, the annual mean conversion rates of the SMA mobile, area, and point sources were 19.3, 10.8, and $6.6{\mu}g/m^3/10^6TPY$ for $SO_2$ emissions while those rates for PPM emissions were 268.6, 207.7, and 181.5 (${\mu}g/m^3/10^6TPY$), respectively, over the region. The results demonstrate that SMA $PM_{2.5}$ responses to the same amount of reduction in precursor emissions differ for source categories and in time (e.g. seasons), which is important when the cost-benefit analysis is conducted during air quality improvement planning. On the other hand, annual mean $PM_{2.5}$ sensitivities to the SMA $NO_x$ emissions remains still negative even after a 50% reduction in emission category which implies that more aggressive $NO_x$ reductions are required for the SMA to overcome '$NO_x$ disbenefit' under the base condition.

Comparison of Eating Habits and Dietary Intake Patterns between People with and without Allergy (알레르기 질환 유무에 따른 식생활 습관과 식품섭취패턴의 비교 연구)

  • Yang, Seung-Hye;Kim, Eun-Jin;Kim, Young-Nam;Seong, Ki-Seung;Kim, Sung-Soo;Han, Chan-Kyu;Lee, Bog-Hieu
    • Journal of Nutrition and Health
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    • v.42 no.6
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    • pp.523-535
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    • 2009
  • The aim of this study was to examine and compare the eating habits and dietary intake patterns of people with or without allergy by the survey during August-September, 2008. The 131 subjects aged 10'-50' (AG = allergy group, n = 62; NG = non-allergy group, n = 69) participated in this study. The questionnaire included general characteristics, dietary habits, and food frequency. Income level tended to be higher in AG than in NG, and AG had more pets and flower pots than NG (p < 0.01). In AG, most affected area of allergy was the skin and the subjects in AG experienced the mixed symptoms and more than 2 types of allergy. Family history of allergy was highly related with allergy of the subjects (AG: 66.1%, NG: 33.9%). Both groups did not exercise regularly, but frequency of alcohol drinking in AG was significantly higher than in NG (p < 0.01). AG skipped meals and had snacking more often than NG (p < 0.05). Most favorite snacks in AG were instant foods, fast foods, cookies, and ice cream (p < 0.05). Therefore, AG tended to consume more allergy-related foods than NG. Highly-consumed allergy-related foods were egg, pork, walnut, onion, tuna, shellfish, and kiwi (p < 0.05). Therefore, nutrition education and guidance is needed to establish good eating habits, food intakes, and life style in people having allergy.