• Journal of Preventive Medicine and Public Health
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• 제44권1호
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• pp.41-47
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• 2011

Objectives: This study assessed the factors that have an influence on the residents exposed to heavy metals, and we utilized the findings to establish the proper management of abandoned metal mines in the future. Methods: For a total of 258 residents who lived close to abandoned mines in Gangwon-province and Gyeonggi-province, the exposure factors and biomarkers in their blood and urine were comparatively analyzed via multiple regression analysis. Results: The blood levels of lead and mercury and the cadmium levels in urine were found to be higher in the study group than that in the average Korean. For the blood levels of heavy metals according to each exposure factor, all of them were found to be significantly higher in both of the group residing for a longer period of time and the group living closer to the source of pollutants. Multiple regression analysis disclosed that all the heavy metals, except lead, in their blood were significantly reduced in proportion to the increased distance of inhabitancy from the mines. Their other biomarkers were within the normal ranges. Conclusions: We found that the distance between the residential village and the mines was a factor that affects the blood level of heavy metals in the villagers. This finding could be an important factor when developing a management model for the areas that surround abandoned metal mines. (ED note: I much like this important study.)

• 한국환경보건학회지
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• 제33권5호
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• pp.386-391
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• 2007

Mercury contamination and its health effects have become major concern of environmental health study in Korea. Mercury exposure of some group were investigated to get the accurate data for policy making and study. About 2,000 children at 26 elementary schools participated in this survey to evaluate the exposure levels and to investigate main exposure source of mercury. Analysis of mercury levels in the whole blood and urine samples were conducted and questionnaire survey was done about the factors influencing exposures simultaneously. Mercury exposure levels of domestic children were N.D. to 17.26 ppb in blood, 0.17 to $21.67{\mu}g/g$-creatinine in urine. The mean(arithmetic) levels are 2.42 ppb in blood and $2.53{\mu}g/g$-creatinine in urine. Both of them were below the recommendation levels of US EPA and German CHBM I $5.8{\mu}g/l$ and $5{\mu}g/l$ in blood, $5{\mu}g/g$-creatinine of German CHBM I in urine. But 1%, 0.51% of levels in blood exceed the level of CHBM I and US EPA, 8%, 0.85% of children were over the level of CHBM I and CHBM II in urine. Multi-valuable regression analysis showed that the existence of road near the residence in addition to the preference for fish have significance with blood mercury exposure level of domestic children. The existence of factory near the house and the experience of dental amalgam treatment had statistical relations with urine mercury level.

• 한국환경과학회지
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• 제25권10호
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• pp.1349-1368
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• 2016

Concentrations of fine particulate matter ($PM_{2.5}$) and several of its particle constituents measured outside homes in Houston, Texas, and Los Angeles, California, were characterized using multiple regression analysis with proximity to point and mobile sources and meteorological factors as the independent variables. $PM_{2.5}$ mass and the concentrations of organic carbon (OC), elemental carbon (EC), benzo-[a]-pyrene (BaP), perylene (Per), benzo-[g,h,i]-perylene (BghiP), and coronene (Cor) were examined. Negative associations of wind speed with concentrations demonstrated the effect of dilution by high wind speed. Atmospheric stability increase was associated with concentration increase. Petrochemical source proximity was included in the EC model in Houston. Area source proximity was not selected for any of the $PM_{2.5}$ constituents' regression models. When the median values of the meteorological factors were used and the proximity to sources varied, the air concentrations calculated using the models for the eleven $PM_{2.5}$ constituents outside the homes closest to influential highways were 1.5-15.8 fold higher than those outside homes furthest from the highway emission sources. When the median distance to the sources was used in the models, the concentrations of the $PM_{2.5}$ constituents varied 2 to 82 fold, as the meteorological conditions varied over the observed range. We found different relationships between the two urban areas, illustrating the unique nature of urban sources and suggesting that localized sources need to be evaluated carefully to understand their potential contributions to $PM_{2.5}$ mass and its particle constituents concentrations near residences, which influence baseline indoor air concentrations and personal exposures. The results of this study could assist in the appropriate design of monitoring networks for community-level sampling and help improve the accuracy of exposure models linking emission sources with estimated pollutant concentrations at the residential level.

• 한국대기환경학회지
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• 제31권5호
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• pp.461-471
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• 2015

Base on emission factors derived from National Institute of Environmental Research, Particulate matter from combined cycle power plants (CCPPs) has been estimated to be a important source of $PM_{10}$. Generally there is no serious emission of particulate matter in CCPPs. because the fuel of them is natural gas. But emission gas after long shut down season has very high dust content. Therefore $PM_{10}$ emission rate is dependent on its operation mode. In this study, particulate dispersion study for new city near CCPPs complex has performed using CALPUFF model for three case. $PM_{10}$ concentration has big difference between normal operation and 2 case start-up condition after long shutdown. In normal operating conditions, daily $0.32{\sim}0.50{\mu}g/m^3$ influence on of the surrounding area. But when 1~2 aerobic high concentration discharged conditions, average concentration is higher about $9.2{\sim}34.1{\mu}g/m^3$ than normal operating conditions.

• Journal of Korean Society for Atmospheric Environment
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• 제15권E호
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• pp.39-43
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• 1999

To help idntify the potential sources of volatile organic sulfur compounds within the continental environment, we have conducted preliminary measurements of dimethylsulfide(DMS) during field campains held from three reference sites. These sampling sites were located within a waste reclamation facility in Won Ju City, Kang Won Province. The results of our measurements showed that DMS levels spanned over 1 to 55 pptv with a mean and 1 standard deviation(1SD) of 12 and 18 pptv(N=13). In a comparison of the data derived from the strongest sources, i.e., oceanic environment, the DMS levels in thre reclamation facility were jpronouncingly low with high day-to-night concentration ratios. It was noted that a significant difference in DMS levels between daytime and nighttime periods was mainly driven by a few exceptional data measured during daytime. Despite limitations of our measurement data in deriving meaningful interpretations of spatiotemporal distributions of DMS in inland facilities, the existence of extraordinary trends, i.e., especially "lower-than-expectedL" DMS values, can be explained in terms of mixed effects of several factors. Most importantly, we can infer that the rates of DMS production and of its destruction in the study site are at or near steady-state condition. Another possibility is that DMS is not adequate enough to explain the generally malordorous environment of reclamation sites, of particular in Won Ju area.n Ju area.

• 항공우주기술
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• 제11권2호
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• pp.208-215
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• 2012

우주발사체 비행에 의한 발사장 주변의 음향 소음에 대하여 분석하였다. 발사체 엔진 배기 제트에 소음원을 위치시키고 소음의 방향성, 대기 감쇄 등을 고려하여 발사장 주변의 특정 지점에 미치는 소음의 크기를 예측하였다. KSLV-I의 발사 소음을 예측하고 이 결과를 비행시험시의 측정 결과와 비교하였다. 분석 결과는 소음의 방향성에 의해 큰 영향을 받는 것으로 나타났으며 소음 방향성 정보에 대한 적절한 가정에 의해 시험 결과와 예측 결과가 서로 잘 일치하는 것을 확인하였다.

• 대한원격탐사학회지
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• 제38권1호
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• pp.1-20
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• 2022

As unmanned aerial vehicle (UAV) technology grew in popularity over the years, it was introduced for air quality monitoring. This can easily be used to estimate the sidewalk emission concentration by calculating road traffic emission factors of different vehicle types. These calculations require a simulation of the spread of pollutants from one or more sources given for estimation. For this purpose, a Gaussian plume dispersion model was developed based on the US EPA Motor Vehicle Emissions Simulator (MOVES), which provides an accurate estimate of fuel consumption and pollutant emissions from vehicles under a wide range of user-defined conditions. This paper describes a methodology for estimating emission concentration on the sidewalk emitted by different types of vehicles. This line source considers vehicle parameters, wind speed and direction, and pollutant concentration using a UAV equipped with a monocular camera. All were sampled over an hourly interval. In this article, the YOLOv5 deep learning model is developed, vehicle tracking is used through Deep SORT (Simple Online and Realtime Tracking), vehicle localization using a homography transformation matrix to locate each vehicle and calculate the parameters of speed and acceleration, and ultimately a Gaussian plume dispersion model was developed to estimate the CO, NOx concentrations at a sidewalk point. The results demonstrate that these estimated pollutants values are good to give a fast and reasonable indication for any near road receptor point using a cheap UAV without installing air monitoring stations along the road.

• 한국산림과학회지
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• 제78권4호
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• pp.360-371
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• 1989

대기오염(大氣汚染)이 삼림식생(森林植生)에 미치는 영향(影響)을 조사(調査)하기 위하여 온산공단주변(溫山公團周邊) 해송림(海松林)의 지역(地域)에 조사구(調査區)를 설정(設定)하여 환경요인(環境要因)과 수목엽내(樹木葉內) 수용성유황(水溶性硫黃)의 함량(含量), 삼림식생(森林植生)의 구조변화(構造變化) 등(等)을 조사(調査)하여 본 결과(結果)는 다음과 같다. 1) 토양(土壤)의 pH와 전질소함량(全窒素含量), 유기물함량(有機物含量) 등(等)은 오염원(汚染原)에서 가까울수록 대체적으로 낮았으며 토양중(土壤中)의 S함량(含量)은 높은 편이었는데, 특히 토양중(土壤中)의 S함량(含量)과 pH와는 1%수준(水準)에서 상관(相關)이 인정(認定)되었다. 2) 해송엽내(海松葉內)의 수용성유황(水溶性硫黃)의 함량(含量)은 0.1295-0.2515%로서 대체적으로 높았으며, 특히 오염원(汚染源)에 가까운 2, 3조사지(調査地)가 가장 높았다. 3) 출현(出現)된 수종(樹種)의 종수(種數)는 3조사지(調査地)에서 7종(種), 7조사지(調査地)에서 20종(種)이 출현(出現)되어 오염원(汚染源)에 가까울수록 점차 감소현상을 보였으며 거리가 먼 지역(地域)일수록 총개체수(總個體數)와 종다양도(種多樣度), 균재도(均在度)가 증가되었다. 4) 해송집내(海松集內)의 S함량(含量)과 출현종수(出現種數), 종다양도문(種多樣度問)에는 상관관계(相關關係)가 각각(各各) 5%, 1%수준(水準)에서 유의성(有意性)이 인정(認定)되었다. 5) 수종별(樹種別) 우점치(優占値)를 비교(比較)하여 본 결과(結果), 대기오염(大氣汚染)이 심한 지역(地域)일수록 우점치(優占値)가 매우 낮았으나 참나무류는 전조사지(全調査地)에서 비교적 높은 편이었다. 6) 본(本) 조사지(調査地)를 중심(中心)으로 본 대기오염(大氣汚染)에 대한 내성도(耐性度)는 해송(海松)과 졸참나무, 청미래덩굴 등(等)이 대기오염(大氣汚染) 강(强)한 것으로 나타났으며 진달래와 산철쭉, 굴피나무, 해변싸리 좋은 민감(敏感)한 것으로 나타났다.

• 지구물리와물리탐사
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• 제20권3호
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• pp.163-175
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• 2017

육상 탄성파 탐사에서 불규칙한 지표 고도차와 천부 지층의 풍화대는 자료의 반사파 신호를 왜곡시킨다. 그러므로 일반적인 육상 탄성파 탐사 자료는 정적 보정(static correction)을 통해 이러한 왜곡을 보정해야 한다. 정적 보정을 하기 위해 천부 지층의 속도가 필요하며, 이 속도는 굴절법 탐사를 통해 구할 수 있다. 그러나 육상 탄성파 탐사자료는 탐사 현장에 대한 허가나 현장 여건 그리고 장비 보유 현황에 따라 제한된 형태로 취득되는 경우가 많다. 이러한 상황에서는 송수신기 배열이 제한되어 굴절법 탐사에 적합한 자료를 얻을 수 없기 때문에 반사법 자료로 굴절법 해석을 수행할 수 밖에 없다. 따라서 본 연구에서는 불규칙 지표 모델에서 제한된 송수신기 배열을 이용하여 얻은 반사법 자료로 굴절 주시 역산을 수행하고 결과의 신뢰성을 분석하였다. 불규칙한 지표와 평탄한 지표를 갖는 모델에 대한 역산 결과를 비교하여 지표 고도 차이가 역산 결과의 신뢰성에 약간의 영향을 주는 것을 확인하였다. 또한, 송신원 개수에 따른 역산을 통해 극히 적은 수의 송신원이 아니라면 역산 결과의 신뢰성에 크게 영향을 주지 않음을 보였다. 반면에 제한된 배열의 수신기를 사용할 경우에는 수신기 전개영역의 중첩된 부분에서 속도왜곡이 발생함을 관찰하였고, 속도왜곡이 발생하지 않기 위한 최소 중첩영역의 크기를 제안하였다. 마지막으로 현장 자료의 지형 조건과 송수신기 배열 정보를 이용하여 수치 모형 실험을 수행하였고, 신뢰성 분석 결과를 검증하였다. 신뢰성 분석 결과를 토대로 현장 자료 역산 결과에 신뢰할 수 있는 영역과 해석에 유의해야 할 영역을 구분하였다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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• pp.210-218
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• 2000

Since the SSC(soluble solid contents) and titratable acidity of fruit are highly concerned to the taste, the need for measuring them by non-destructive technology such as NIR(Visual and Near-infrared) spectroscopy is increasing. Specially, in order to grade the quality of each fruit with a sorter at sorting and packing facilities, technologies for online measurement satisfying the tolerance in terms of accuracy and speed should be developed. Many researches have been done to develop devices to measure the internal qualities of fruit such as SSC, titratable acidity, firmness, etc. with the VIS(Visual)/NIR(Near Infrared) reflectance spectra. The distributions of the SSC, titratable acidity, firmness, etc. are different with respect to the position and depth of fruit, and generally the VIS/NIR light can interact with fruit in a few millimeters of pathlength, and it is very difficult to measure the qualities of inner flesh of fruit. Therefore, to measure the average concentrations of each quality factor such as SSC and titratable acidity with the reflectance-type NIR devices, the spectra of fruit at several positions should be measured. Recently, the interest about the transmittance-type VIS/NIR devices is increasing. NIR light can penetrate through the fruit about 1/10-1/1,000,000 %. Therefore, very intensive light source and very sensitive sensor should be adopted to measure the transmitted light spectra of intact fruit. The ultimate purpose of this study was to develop a device to measure the transmitted light spectra of intact fruit such as apple, pear, peach, etc. With the transmittance-type VIS/NIR device, the feasibility of measurement of the SSC and titratable acidity in intact fruit cultivated in Korea was tested. The results are summarized as follows; A simple measurement device which can measure the transmitted light spectra of intact fruit was constructed with sample holder, two 500W-tungsten halogen lamps, a real-time spectrometer having a very sensitive CCD array sensor and optical fiber probe. With the device, it was possible to measure the transmitted light spectra of intact fruit such as apple, pear and peach. Main factors affecting the intensity of transmitted light spectra were the size of sample, the radiation intensity of light source and the integration time of the detector. Sample holder should be designed so that direct light leakage to the probe could be protected. Preprocessing method to the raw spectrum data significantly influenced the performance of the nondestructive measurement of SSC and titratable acidity of intact fruit. Representative results of PLS models in predicting the SSC of peach were SEP of 0.558 Brix% and R2 of 0.819, and those in predicting titratable acidity were SEP of 0.056% and R2 of 0.655.