PURPOSES : In this study, the characteristics of fine particulate matter (PM2.5) concentrations under different weather conditions of different types of bus stops, such as enclosed-type and open-type bus stops, were analyzed using statistical methods. METHODS : Data was collected inside and outside an enclosed bus stop on sunny and rainy days to compare and analyze the characteristics of fine particulate matter concentration in the target bus stop. The probability distributions were estimated for each data point using the Anderson–Darling test. Based on the estimated probability distributions, probability density functions were computed, and the values were used to estimate and compare probability for each air quality index inside and outside the bus stop under different weather conditions RESULTS : For the results of descriptive statistics, the average concentrations of fine particulate matter inside and outside the bus stop were 42.296 and 35.482 μg/m3 on a sunny day and 40.831 and 39.321 μg/m3 on a rainy day, respectively. Results of the statistical method, obtained using the Anderson-Darling test, indicate that the probability of the air quality index inside the bus stop reaching high concentrations on a sunny day was "high" or "very high," compared to that outside the bus stop. However, on rainy days, the differences in fine particulate matter concentrations inside and outside the bus stops were difficult to identify based on statistical evidence. CONCLUSIONS : It was found that the open-type bus stop had an advantage of preventing fine particulate matter effects on sunny days, compared to the enclosed-type bus stops. Furthermore, there were slight differences in fine particulate matter concentrations inside and outside the bus stop on a rainy day because of atmospheric flow and stormwater.

PURPOSES : A pilot experimental study on the formation of fine particulate matter through photochemical reactions using precursor gas species (volatile organic compounds (VOCs), NH3, SO2, and NOx) was conducted to evaluate the large-scale environment chamber for investigating the pathway of aerosol formation and the subsequent assessment techniques used for reducing fine particulate matter. Two small-scale environment chambers (one experimental group and one control group), each with a width, depth, and height of 3 m, 2 m, and 2.3 m, respectively, were constructed using ethylene tetrafluoroethylene (ETFE) films. METHODS : The initial conditions of the fine particles and precursor gases (NOx and VOCs) for the small-scale environment chamber were set up by injecting diesel vehicle exhaust. NH3 and H2O2 were added to the small-scale environment chamber for the photochemical reaction to form organic and inorganic aerosols. The gas phase of the VOCs and the chemical compositions of aerosols were investigated using a proton transfer reaction time-of-flight mass spectrometer and the aerodyne high-resolution time-of-flight aerosol mass spectrometer at 1 and 10 s time resolutions, respectively. Gas phases of NO and NO2 were measured using Serinus 40 NOx at a 20 s time resolution. RESULTS : The small-scale environment chambers built using ETFE films were proved to supply sufficient natural sunlight for the photochemical reaction in the environment chambers at an average of approximately 89% natural sunlight transmission at 300–1000 nm. When the intermediates of NH3 and H2O2 for the atmospheric chemical reaction were injected for the initial condition of the small-scale environment chamber, nitrate and ammonium in the experimental group increased to 4747% and 1837%, respectively, compared to the initial concentrations (5.4 μg/m3 of nitrate and 5.2 μg/m3 of ammonium), indicating the formation of secondary inorganic aerosols of ammonium nitrate (NH4NO3). This implies that it is necessary to inject intermediates (NH3 and H2O2) for the formation of fine particulate matter when simulating the atmospheric photochemical reaction for assessing the environment chamber. CONCLUSIONS : This study has shown that small-scale environment chambers can simulate the atmospheric photochemical reaction for the reduction of fine particulate matter and the formation of the aerosol pathway. The results of this study can be applied to prevent time and economic losses that may be incurred in a full-scale environment chamber.

본 연구는 서대전광장의 이용자들의 공간별 이용실태 분석을 통하여 서대전광장이 어떻게 이용되고 있는지를 파악하고, 이용객들의 만족도와 향후 도입 가능한 편익들 중 이용객들이 가장 중요하게 생각하는 것이 어떤 것들인지 도출하여 서대전광장의 활성화를 위한 기초자료를 제공하기 위해 수행하였다. 연구결과 서대전광장 이용객들은 대전시가 사유지를 매입하여 녹지를 지킨 것에 대하여 75.26% 가 잘하였다고 생각하며, 향후에도 토지를 구매하여 녹지로 보존하는 것에 동의하고 있었다. 하지만 시민들의 매입비용을 부담하는 것에는 부정적이었다. 향후 발전 방향을 위한 편익에 대한 질문에는 체험 공간 보다는 정적이면서 스트레스의 해소와 환경적인 만족도와 편익의 중요도가 서로 상관관계를 가지며 만족도가 높은 프로그램들을 실현하는 편익들이 더 중요하게 간주되고 있다는 결과가 도출되었다. 따라서, 본 연구에서는 녹지를 보존하기 위하여 지자체가 토지를 구입하는 것에 긍정적 반응을 보이고 있으나 개인이 지불할 의사는 낮은 것으로 나타났으며, 만족도를 높이는 요인들은 체험활동 보다 친 자연적인 요인들이 중요하며, 휴식과 휴양에 중점을 둔 발전 방향을 구성하는 것이 바람직하다고 결론지었다.

This study analyzed the health characteristics and comorbidity of adult men aged 40 years by dividing them into a control group of those without any disease related to fine dust and a patient group with one or more diseases related to fine dust in areas with high levels of fine dust pollution using the sixth and seventh Korea National Health and Nutrition Examination Survey (2013-2017). Among the general characteristics, the mean age of the patient group was significantly older than that of the control group (p<0.001), and in terms of the health-related characteristics, the frequency of breakfast consumption in the patient group was higher than in the control group (p<0.043). The body measurements were similar in the patient and control groups. Regarding the prevalence of comorbidity, the patient group showed a higher prevalence of hypertension, dyslipidemia, stroke, myocardial infarction, heart failure, and diabetes than the control group, but the differences were not statistically significant. On the other hand, the prevalence of other cancers (except stomach cancer, liver cancer, colorectal cancer, breast cancer, and cervical cancer) in the patient group was higher than in the control group (p<0.05). In terms of the clinical characteristics, the glycated hemoglobin levels in the patient group were significantly higher than in the control group (p<0.048). Information on nutrition and health in areas with frequent occurrences of fine dust was obtained through the study results, which can be used as basic data for measures of health and diet management against diseases that will increase in relation to fine dust.

본 논문은 버스정류장 미세먼지 저감을 위해 설계된 도로시설물의 성능평가 과정 및 결과를 보고한다. 먼저, 유한요 소해석 프로그램인 LS-DYNA를 이용하여 대상 구조물에 대한 충돌해석이 수행되었다. 해석변수로 차량의 속도와 충돌 위치를 고려한 다양한 조건에서의 구조해석이 진행되었다. 대상 시설물의 성능은 이 결과를 이용하여 구조적 성능과 충돌 후 차량의 안전성능이 평가되었다. 해석결과로부터 충돌속도가 증가하고 충돌위치가 전면으로 갈수록 시설물의 구조성능과 차량의 충돌 후 안전성능이 저하되는 것이 콘크리트의 손상량을 통해 확인되었다. 더불어 충돌 후 차량의 거동에 대한 분석을 통해 시설물에 연속되는 연석이 설치되면 차량의 이탈을 방지해 안전성능을 확보하는 것으로 예측되었다. 최종적으로, 대상 시설물은 설계 시 고려된 목표 충돌속도 25km/h보다 더 큰 40km/h까지 충분한 안전성능을 확보하고 있다는 것이 확인되었다.

PURPOSES : This study analyzes the characteristics of generated fine particulate matter (PM2.5) and nitrogen oxide (NOX) at roadsides using a statistical method, namely, a generalized linear model (GLM). The study also investigates the applicability and capability of a machine learning methods such as a generalized regression neural network (GRNN) for predicting PM2.5 and NOX generations. METHODS : To analyze the characteristics of PM2.5 and NOX generations at roadsides, data acquisition was conducted in a specific segment of roads, and PM2.5 and NOX prediction models were estimated using GLM. In addition, to investigate the applicability and capability of a machine learning methods, PM2.5 and NOX prediction models were estimated using a GRNN and were compared with models employing previously estimated GLMs using r-square, mean absolute deviation (MAD), mean absolute percentage error (MAPE), and root mean square error (RMSE) as parameters. RESULTS : Results revealed that relative humidity, wind speed, and traffic volume were significant for both PM2.5 and NOX prediction models based on estimated models from a GLM. In addition, to compare the applicability and capability of the GLM and GRNN models (i.e., PM2.5 and NOX prediction models), the GRNN model of PM2.5 and NOX prediction was found to yield better statistical significance for r-square, MAD, MAPE, and RMSE as compared with the same parameters used in the GLM. CONCLUSIONS : Analytical results indicated that a higher relative humidity and traffic volume could lead to higher PM2.5 and NOX concentrations. By contrast, lower wind speed could affect higher PM2.5 and NOX concentrations at roadsides. In addition, based on a comparison of two statistical methods (i.e., GLM and GRNN models used to estimate PM2.5 and NOX), GRNN model yielded better statistical significance as compared with GLM.

In this study, we evaluated the filtering effect of the fine dust mask. Our objective research has secured credibility in the private sector. The performance of domestic fine dust masks is evaluated by three dust collection efficiencies, inspiratory resistance, and leakage rate according to KF grade in the health mask standard guidelines issued by the Ministry of Food and Drug Safety. Based on this, eight types of fine dust masks were evaluated for dust collection efficiency and face intake resistance. All masks showed good performance as the collection efficiency was 90%. The higher the KF grade, the higher the collection efficiency, but the inspiratory resistance had no correlation with the grade. According to the manufacturer's operation method, masks below the standard value may be distributed. Masks that are currently on the market have shown results that can be trusted. However, we hope that the system will be improved to validate whether the masks that meet the threshold are still being distributed.

PURPOSES : Over the years, the concentration of fine dust is gradually increasing, thereby aggravating the seriousness of the situation. Accordingly, this study intends to install a clean road system using low impact development (LID) techniques on the roadside in order to reduce the scattering of dust on roads effectively. This system stores rainwater collected through gutters in rainy weather and sprays water onto the pavement surface to reduce the scattering of road dust. METHODS : The developed clean road system consists of a water tank, controller, rain detection sensor, and solar cell. Based on this, a test-bed construction was used to evaluate its applicability. By applying the developed system, actual applicability was evaluated through total suspended solid (TSS) test and fine dust measurement. TSS test was conducted to measure the reduction rate of scattering dust on the road owing to the water injected by the clean road system. A spray nozzle was used for the TSS test, and a nebulization nozzle was used for the measurement of fine dust. In order to increase the reliability of the test, three measurements were taken each, for normal road as well as unfavorable conditions road that reproduced the construction site. RESULTS : In this study, fine dust concentration measurement and TSS test were conducted to evaluate the practical applicability of the developed clean road system. From the TSS test, it was found that for both general roads and roads depicting bad conditions, the TSS value after the first spray was the highest, and the value after the second spray was sharply reduced, such that most of the re-dispersed dust was washed out after the first spray, and similar TSS value results were obtained after the third spray. Based on this result, the result of fine dust measurement showed similar fine dust reduction effect of 9%-15.9% regardless of the concentration of fine dust in the atmosphere. These results indicate that the concentration of fine dust in the atmosphere does not significantly affect of the degree of reduction in fine dust. CONCLUSIONS : In this study, a clean road system for reducing fine dust on the road was developed and its applicability was evaluated. In a future study, we intend to check the performance of the drainage pavement through performance evaluation of water permeability coefficient test and performance test in the form of drainage pavement. Through this, we intend to evaluate the applicability of the clean road system to which drainage pavement is applied. Moreover, we will develop a clean road system that applies drainage packaging, and analyzes the degree of fine dust reduction according to the spray angle, spray amount, and spray time of the clean road system in order to study the spray system with the optimum amount of fine dust reduction. In addition, in order to reduce fine dust in the winter, when fine dust is mainly generated, it is planned to install heating wires in spray pipes where freezing is expected. Lastly, the black ice prevention effect will be analyzed by mixing a certain amount of sodium chloride when spraying water.

PURPOSES : Concrete pavement is excellent in structural performance and durability. However, its functionality – such as noise and skid resistance – is a shortcoming. Functionality such as noise reduction and skid resistance of concrete pavement is affected by the texture surface, and the texture surface is classified according to the length of the wavelength. In recent years, Fine-size exposed aggregate concrete pavement has been applied, which has excellent structural performance and durability, and secures functionalities such as noise reduction and long-term skid resistance by randomly forming texture surface. Fine-size exposed aggregate concrete pavements are constructed by removing the surface cement binder to randomly expose coarse aggregate and their functionality is mainly governed by the surface texture. However, deteriorated concrete by tire-pavement friction and deicing agent may cause abrasion and aggregate loss on the surface texture; thus reducing their functional performances. Abrasion is created by the thin cutoff of aggregate texture under repeated tire-pavement friction. In addition, aggregate loss is defined by the detachment of aggregates from cement binder. This study aims to evaluate the abrasion and aggregate loss of Fine-size exposed aggregate concrete pavement surface texture under tire-pavement friction and scaling tests. METHODS : In the study, abrasion and aggregate loss of tining and exposed aggregate concrete surface treatments were evaluated. Deterioration of each surface treatment was replicated by scaling test under ASTM C 672 test method. Afterward, abrasion test was conducted by ASTM C779 to simulate the tire-pavement friction under traffic. Consequently, abrasion and aggregate loss were measured. RESULTS : Abrasion depth of non-scaling tining, 10-mm EACP, and 8-mm EACP was 1.76, 1.12, and 1.01mm, respectively. Compared to scaling surface treatments, the difference of abrasion depth in tining texture was the largest with value of 0.4mm. For both textures of finesize exposed aggregate concrete, abrasion depth difference was about 0.1mm. Moreover, The 10-mm EACP exhibited a 2.6% of aggregate loss rate caused by tire-pavement friction before conducting concrete deterioration test. After 40-cycle scaling test, aggregate loss increased up to 12.2%. For 8-mm EACP, aggregate loss rate was 1.7% on non-scaling concrete. Further, this rate was magnified up to 7.3% for the 40-cycle scaling concrete. CONCLUSIONS : Under non-scaling or scaling tests, fine-size exposed aggregate concrete pavement showed better abrasion resistance than tining texture since tining was formed by aggregates and cement binder. Additionally, rate of aggregate loss was significant when EACP experienced the deicing agent under numerous cycles of freeze-thaw action.

본 연구에서는 복잡한 도심의 구조로 인한 미세먼지 농도의 강화 가능성에 대하여 데이터 마이닝 기술과 군집분석을 이용해 조사하였다. 데이터 마이닝 분석에서 미세먼지 농도와 서울지역 도시용도 데이터 사이에는 유의한 상관관계를 보이지 않았다. 그러나 전국 공공데이터를 기반으로 한 군집분석에서는 건물의 높이(층수)에서 특히 PM10과 강한 상관관계가 나타났다. 단일 케노피 모델(Single Canopy Model) 및 미기상 도시모델링 프로그램(ENVI-Met.4)을 사용한 모델링 분석을 실시하여 도시지역에서 모사된 대기 대류가 건물 분포 및 높이 유형의 배열에 따라 다양한 난류의 패턴을 구현함을 확인하였 다. 도시 건물의 복잡한 구조는 대류활동을 제어하여 정체상태를 유도하고 지표 부근의 미세먼지 강화가능성을 초래 하였다. 따라서 도심 구조와 형태에 따른 열환경의 변화로 인한 정체 효과는 미세먼지 산정에 있어서 반드시 고려되어야 한다. 복잡한 도시지역의 미세먼지 잔류확률에 대한 정보를 제공하기 위해서는 대기정체 현상이 중요한 의미로 해석될 수 있다.

본 연구는 미세먼지 문제 속에서의 환경권 보장에 대한 연구이다. 미세먼지가 사회문제로 이슈화되고 이에 대한 국민의 환경권에 대한 논의를 한 뒤, 미세먼지와 관련된 판례에서 나타난 국민이 건강하게 좋은 환경에서 살아갈 권리를 조명한다. 특히 국내 판결에서 건강권과 관련하여 배출가스 또는 미세먼지가 질병에 미치는 영향의 과학적 입증이 필요함을 강조한다. 연구를 통해 국민의 환경권을 보장하고 환경 불평등을 완화하며 환경 정의를 실현하기 위해 미세먼지 문제의 해결이 요원함을 알 수 있었다. 미세먼지 농도와 환경기준 미달성률, 시도별 미세먼지 현황을 검토하며 국가 및 지자체가 법제를 통해 심화되는 미세먼지 문제를 해결하려는 노력을 알 수 있었다. 미세먼지로부터 받는 영향력이 소외계층에게 더욱 컸고, 지역별로도 미세먼지의 피해가 다양하게 나타났고 이에 대응한 조례들도 제정되고 있다. 또한 본 연구에서 미세먼지와 관련한 판결들을 분석하였고 각종 미세먼지의 원인과 손해, 국가배상, 배출금지와 관련된 판례에서 과학기술 연구 결과를 인용하고 그 측정치 내지 분석결과나 논문을 판단의 잣대로 삼았다는 것을 알 수 있었다. 우리나라에선 미세먼지가 국민 질병에 미치는 피해와 관련한 소송이 있었지만 법원이 인정하지 않았다. 한국은 지금까지 개별적 인과관계를 인정하지 않았지만 대법원과 헌법재판소에 판례에 따르면 실제 전국에 걸쳐 국민들이 대기환경으로 피해를 보고 있는 경우 국가가 책임을 회피하기는 어려울 것이다. 이러한 과학적 인과관계 입증의 어려움이 컸던 기존 판례의 어려움을 통해 보았을 때 미세먼지 문제를 해결하기 위한 과학기술정책과 법제의 지원이 필요하다. 한국에 부족한 미세먼지 관련 연구개발을 중흥하기 위한 국가 주도의 법정책이 필요하며 국가기후환경위원회를 통해 과학적 사실과 국민인식의 괴리를 좁히는 노력도 필요하다. 또한 항만지역 등 미세먼지발생이 높은 섹터에 대한 정보체계관리와 과학기술을 통한 배출물질과 오염의 인과관계를 밝히는 노력이 필요하며 이를 위한 법제 지원도 중요한 요소로 판단된다.

최근 한국에서 미술품 시가감정은 미술시장 활성화를 위한 방안이자 감정학의 일환으로 부상해 있다. 그런데 수량화시킨 미술품의 경제적 가치 분석을 시장에 기반해 제시하는 그 접근법은 진위분별과 미적이고 질적인 특징의 분석에 매진해온 감정학의 일반 개념과 큰 차이가 있다. 감정평가단체가 많고 미술품 전담 감정평가사가 전문적으로 활동하면서 관련 교육을 담당하는 전문기관이 있는 미국의 경우는 그 업무의 전체 과정에 접근하기가 용이하다. 본고는 미국에서의 미술품 감정평가 업무수행의 전체적인 면모를 소개한 뒤 한국의 현황과 비교해 시가감정을 자산평가 분야의 일환으로 파악하고자 한 것이다. 미국의 미술품 감정평가 과정은 사용자의 필요와 용도에 합당한 가치평가 유형의 결정, 평가대상의 상태와 적합한 시장에 대한 분석, 최종가치진술로서의 가치평가액 도출 등의 전체과정이 최종가액 판단을 위한 근거자료와 더불어 문서화되어 전문가적인 의견 피력의 무대가 확보되어 있다. 그 업무수행과 산출결과에 대한 신뢰의 배경에 USPAP이 있고, 윤리성을 강조한 그 규정에 입각해 작성된 감정평가서는 성실한 업무수행의 전과정을 그대로 드러낸 다. 이를 고찰하면, 상황에 따라 변하기 마련인 미술품 가격 자체에만 집착하며 진위감정과 시가감정의 개념과 범주를 혼동해온 한국의 현실을 깨닫게 된다. 더불어 사용자의 필요를 해결하기 위해 성실하고 정확하고 윤리적으로 합당하게 수행된 전문가의 작업이 신뢰받는 자산 평가로 귀결되어지도록 시가감정의 개념과 작업방식을 재정비해 미술품 자산가치 평가방식 을 확립할 필요가 있음을 느끼게 된다. 진위감정과 별도로 미술품의 자산가치를 객관적으로 평가해줄 시가감정 영역의 정비와 방법론 계발이 요청되는 것이다.

PURPOSES: The noise problem in concrete pavements has an adverse effect to the road user or nearby residents and is generated by the contact between a tire and the pavement surface. Exposed aggregate concrete pavements have been adopted to solve the tire-pavement noise problem in the United States and Europe. However, the efficiency of the coagulation retarder and exposure equipment used for this kind of pavement has not yet been investigated. Therefore, this study aims to evaluate the ability of the coagulation retarder and exposure equipment in producing the optimum exposed aggregate texture to achieve low pavement noise. A method for the exposure time selection has also been introduced here. METHODS: Sodium gluconate retarders were selected for use in this study. The retarder-water ratios of 1:1, 1:2, and 1:3 were investigated. The retarder was sprayed on a fresh concrete surface with rates of 200 g/m2, 300 g/m2, and 400 g/m2. The aggregates were then exposed to the surface using a steel brush and a water jet. The efficiencies for the low-noise texture, workability, and environmental impact produced by the two exposure devices were estimated. The EAN and the MTD were investigated according to the exposure time. RESULTS : The aggregates were exposed after the retarder was sprayed on the fresh concrete surface; the exposure lasted for 18 h to 26 h each time. The retarder-water ratio of 1:2 and the spraying rate of 300 g/m2 produced an optimum surface texture for low noise. Additionally, the steel brush performed more effectively in exposing aggregate to the surface compared to the water jet. The selected exposure time window (ETW) was 28 h to 35 h. CONCLUSIONS : The optimum retarder was the sodium gluconate retarder with a retarder-water ratio of 1:2 and a spraying rate of 300 g/m2. The steel brush showed a good performance in exposing the aggregates and showing the efficiency of the coagulation retarder in the given environment so as to produce the quality control condition. The ETW was influenced by the construction, mixture design, and construction environment; however, the selected ETW in this study was 26 h~35 h.

PURPOSES : In many European countries, the fine-size exposed aggregate concrete pavement (EACP) technique has been adopted for a quiet pavement. However, different noise reduction levels were reported based on the mixture design and texture conditions. This study aims to suggest a quality control condition for achieving low-noise texture and a mixture design procedure for exposed aggregate concrete overlay (EACO), which will provide the optimum mixture of the surface texture that can reduce the tire-pavement noise. METHODS : The tire-pavement noise is highly influenced by the pavement surface texture. The surface texture of the EACP can be quantified by the mean texture depth (MTD) and the exposed aggregate number (EAN). The optimum condition for the low-noise texture of the EACP was investigated herein based on the analysis of the review of the texture conditions and noise measurement in many EACP sites. RESULTS : The MTD and EAN criteria can be derived according to the investigated relationship between noise and texture condition. The optimum mixture design to satisfy these criteria can be achieved by controlling the maximum size of the coarse aggregate and the S/a. CONCLUSIONS: This study aimed to suggest a quality control condition for achieving low-noise texture and an optimum mixture design for EACO. As a result, we found that the early traffic opening of EACO can be achieved by using high early-strength cement.

본 연구는 도로시설물의 염화칼슘 제거를 위한 미세기포 세척장비의 최적 운용조건에 대하여 성능평가를 수행하였다. 실험에 사용된 미세기포의 직경은 196.6±100.6nm 에 1.36×108개/ml의 농도를 나타낸다. 세척장비의 분사장치에 대한 실험 성능결과, 100bar의 분사압력에서 100cm, 150cm 분사거리에 약 93%, 91%의 세척효율이 나타나는 것으로 확인되었다. 미세기포 생성(순환)횟수를 2-6회로 증가시킴에 따라 최소 1%에서 7%까지 염화물 제거율이 높아짐을 확인하였다. 미세기포 생성 공기유량을 4 ml/min에서 0.5 ml/min으로 낮춤에 따라 세척효율이 최대 30%까지 증가하는 것이 확인되었다. 일반 상수도와 미세기포의 세척효율은 미세기포가 일반상수도 보다 세척효율이 25% 높게 나타났다.