• Title/Summary/Keyword: 먼지

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Analysis of the Priority of Evaluation Criteria and Detailed Index for Selecting Street Trees (가로수 선정 평가기준과 세부지표의 중요도 분석)

  • Kim, Min Kyung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.1
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    • pp.42-53
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    • 2021
  • Street trees improve the cityscape and air quality, reduce heat islands, and create wildlife habitats. Hence, they are essential parts of a city's green infrastructure. Therefore, several trees that are well adapted to the urban environment were planted. However, this caused the problem of simple trees being planted around the world. This study is to select more various street trees. To accomplish this, evaluation criteria and detailed indexes were created. The importance was indicated through the Analytic Hierarchy Process. For commercial roads, the priority of landscape characteristics is 0.2640, and among detailed indicators, the priority of shape is 0.1245. For work roads, the priority of landscape characteristics is 0.2496, and among detailed indicators, the priority of shape is 0.1177. For work roads, the priority of characteristics of civil service is 0.2250, and among detailed indicators, the priority of shape is 0.1177. For general roads, the priority of maintenance characteristics is 0.2479, and among detailed indicators, the priority of shape is 0.1062. For historical and cultural roads, the priority of regional characteristics is 0.3488, and among detailed indicators, the priority of regional characteristics is 0.1643. For ecological roads, the priority of ecosystem characteristics is 0.3488, and among detailed indicators, the priority of the diversity of species is 0.1643. For automotive-only roads, the priority of the ecosystem characteristics is 0.4639, and among detailed indicators, the priority of reducing emissions is 0.1643. This study will provide objective criteria for the selection of street trees.

Measurement of Sulfur Dioxide Concentration Using Wavelength Modulation Spectroscopy With Optical Multi-Absorption Signals at 7.6 µm Wavelength Region (7.6 µm 파장 영역의 다중 광 흡수 신호 파장 변조 분광법을 이용한 이산화황 농도 측정)

  • Song, Aran;Jeong, Nakwon;Bae, Sungwoo;Hwang, Jungho;Lee, Changyeop;Kim, Daehae
    • Clean Technology
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    • v.26 no.4
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    • pp.293-303
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    • 2020
  • According to the World Health Organization (WHO), air pollution is a typical health hazard, resulting in about 7 million premature deaths each year. Sulfur dioxide (SO2) is one of the major air pollutants, and the combustion process with sulfur-containing fuels generates it. Measuring SO2 generation in large combustion environments in real time and optimizing reduction facilities based on measured values are necessary to reduce the compound's presence. This paper describes the concentration measurement for SO2, a particulate matter precursor, using a wavelength modulation spectroscopy (WMS) of tunable diode laser absorption spectroscopy (TDLAS). This study employed a quantum cascade laser operating at 7.6 ㎛ as a light source. It demonstrated concentration measurement possibility using 64 multi-absorption lines between 7623.7 and 7626.0 nm. The experiments were conducted in a multi-pass cell with a total path length of 28 and 76 m at 1 atm, 296 K. The SO2 concentration was tested in two types: high concentration (1000 to 5000 ppm) and low concentration (10 ppm or less). Additionally, the effect of H2O interference in the atmosphere on the measurement of SO2 was confirmed by N2 purging the laser's path. The detection limit for SO2 was 3 ppm, and results were compared with the electronic chemical sensor and nondispersive infrared (NDIR) sensor.

Development of a Cosmetic Ingredient Containing DHA Derivatives for Anti-inflammation, Anti-wrinkle, and Improvement of Skin Barrier Function (DHA 유도체를 이용한 항염, 항노화, 피부장벽 강화용 화장품 원료의 개발)

  • Lee, Miyoung;Lee, Gil-Yong;Suh, Jinyoung;Lee, Kyung min;Lee, Woojung;Cho, Hee Won;Yi, Jong-Jae;Seo, Jeong-Woo;Choi, Heonsik
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.47 no.1
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    • pp.65-73
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    • 2021
  • It is very important to control the inflammation of the skin because it can develop into diseases such as atopy as well as scarring and aging. In this work, we recently identified the in vitro synthesis of specialized pro-resolving mediators (SPMs) known to control inflammation in the human body and the applicability of cosmetics. Using recombinant protein of lipoxygenase from Glycine max, we succeeded to prepare mixtures of mono- or di-hydroxy DHA named as S-SPMs and used them for in vitro efficacy test. To investigate anti-inflammatory effect of S-SPMs, mRNA level of TNF-α and IL-6 were analyzed. Under UVB exposed condition, expression of both were decreased by S-SPMs treatment. And we observed reduced production of nitric oxide (NO) by S-SPMs application under the condition with diesel particulate matter (DPM). At the same experimental condition, malondialdehyde (MDA) production was decreased by S-SPMs, indicating the inhibitory effect of S-SPMs in lipid peroxidation. In addition, S-SPMs treatment resulted in reduction of matrix metalloproteinases-1 (MMP-1) expression and elevation of procollagen type I synthesis. Together with this, mRNA level of filaggrin and loricrin were increased by S-SPMs, indicating enhancement of skin barrier function. These results demonstrate that S-SPMs is a good candidate to develop as a cosmetic ingredient for anti-inflammation, anti-wrinkle, and improvement of skin barrier function.

Investigation on the Preparation Method of TiO2-mayenite for NOx Removal (질소산화물 제거를 위한 TiO2-mayenite 제조 방법에 관한 연구)

  • Park, Ji Hye;Park, Jung Jun;Park, Hee Ju;Yi, Kwang Bok
    • Clean Technology
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    • v.26 no.4
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    • pp.304-310
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    • 2020
  • In order to apply a photocatalyst (TiO2) to various building materials, TiO2-mayenite was prepared in this study. The TiO2 was synthesized using the sol-gel method by fixing titanium isopropoxide (TTIP) and urea at a ratio of 1 : 1. Later, they were calcined in a temperature range of 400-700 ℃ to analyze the properties according to temperature. BET, TGA, and XRD were used to analyze the physical and chemical properties of TiO2. The nitrogen oxide removal test was confirmed by measuring the change in the concentration of NO for 1 h according to KS L ISO 22197-1. The prepared TiO2 samples exhibited an anatase crystal structure below 600 ℃, and TiO2 (urea)-400 showed the highest nitrogen oxide removal rate at 2.35 µmol h-1. TiO2-mayenite was prepared using two methods: spraying TiO2 dispersion solution (s/s) and sol-gel solution (g/s). Through BET and XRD analysis, it was found that 5-TiO2 (g/s) prepared by spraying a sol-gel solution has maintained its crystallinity even after heat treatment. Also, 5-TiO2 (g/s)-500 showed the highest removal rate of 0.55 µmol h-1 in the nitrogen oxide removal test. To prepare TiO2-mayenite, it was confirmed that mayenite should be blended with TiO2 in a sol-gel state to maintain the crystal structure and exhibit a high nitrogen oxide removal rate.

Evaluation and Predicting PM10 Concentration Using Multiple Linear Regression and Machine Learning (다중선형회귀와 기계학습 모델을 이용한 PM10 농도 예측 및 평가)

  • Son, Sanghun;Kim, Jinsoo
    • Korean Journal of Remote Sensing
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    • v.36 no.6_3
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    • pp.1711-1720
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    • 2020
  • Particulate matter (PM) that has been artificially generated during the recent of rapid industrialization and urbanization moves and disperses according to weather conditions, and adversely affects the human skin and respiratory systems. The purpose of this study is to predict the PM10 concentration in Seoul using meteorological factors as input dataset for multiple linear regression (MLR), support vector machine (SVM), and random forest (RF) models, and compared and evaluated the performance of the models. First, the PM10 concentration data obtained at 39 air quality monitoring sites (AQMS) in Seoul were divided into training and validation dataset (8:2 ratio). The nine meteorological factors (mean, maximum, and minimum temperature, precipitation, average and maximum wind speed, wind direction, yellow dust, and relative humidity), obtained by the automatic weather system (AWS), were composed to input dataset of models. The coefficients of determination (R2) between the observed PM10 concentration and that predicted by the MLR, SVM, and RF models was 0.260, 0.772, and 0.793, respectively, and the RF model best predicted the PM10 concentration. Among the AQMS used for model validation, Gwanak-gu and Gangnam-daero AQMS are relatively close to AWS, and the SVM and RF models were highly accurate according to the model validations. The Jongno-gu AQMS is relatively far from the AWS, but since PM10 concentration for the two adjacent AQMS were used for model training, both models presented high accuracy. By contrast, Yongsan-gu AQMS was relatively far from AQMS and AWS, both models performed poorly.

A Numerical Study on the Characteristics of Flows and Fine Particulate Matter (PM2.5) Distributions in an Urban Area Using a Multi-scale Model: Part I - Analysis of Detailed Flows (다중규모 모델을 이용한 도시 지역 흐름과 초미세먼지(PM2.5) 분포 특성 연구: Part I - 상세 흐름 분석)

  • Park, Soo-Jin;Choi, Wonsik;Kim, Jae-Jin
    • Korean Journal of Remote Sensing
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    • v.36 no.6_3
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    • pp.1643-1652
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    • 2020
  • To investigate the characteristics of detailed flows in a building-congested district, we coupled a computation fluid dynamics (CFD) model to the local data assimilation and prediction system (LDAPS), a current operational numerical weather prediction model of the Korea Meteorological Administration. For realistic numerical simulations, we used the meteorological variables such as wind speeds and directions and potential temperatures predicted by LDAPS as the initial and boundary conditions of the CFD model. We trilinearly interpolated the horizontal wind components of LDAPS to provide the initial and boudnary wind velocities to the CFD model. The trilinearly interpolated potential temperatures of LDAPS is converted to temperatures at each grid point of the CFD model. We linearly interpolated the horizontal wind components of LDAPS to provide the initial and boundary wind velocities to the CFD model. The linearly interpolated potential temperatures of LDAPS are converted to temperatures at each grid point of the CFD model. We validated the simulated wind speeds and directions against those measured at the PKNU-SONIC station. The LDAPS-CFD model reproduced similar wind directions and wind speeds measured at the PKNU-SONIC station. At 07 LST on 22 June 2020, the inflow was east-north-easterly. Flow distortion by buildings resulted in the east-south-easterly at the PKNU-SONIC station, which was the similar wind direction to the measured one. At 19 LST when the inflow was southeasterly, the LDAPS-CFD model simulated southeasterly (similar to the measured wind direction) at the PKNU-SONIC station.

An Analysis of the Relative Importance of Park Services for User-Oriented Smart Park Development (이용자 중심의 스마트공원 조성을 위한 공원서비스의 상대적 중요도 분석)

  • Lee, Ju-Yong;Lee, Hyung-Sook
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.4
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    • pp.55-63
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    • 2021
  • Interest in smart parks has been increasing due to the recent rapid rise of smart cities, but concerns are growing over the development of technology-oriented smart parks. The purpose of this study is to evaluate the relative importance of park services through Focus Group Interviews and the Analytic Hierarchy Process (AHP) to develop user-oriented smart parks in the future. To this end, literature on park functions and services was reviewed, and interviews with experts in the field of landscape architecture and IT were conducted to derive service items. The AHP model consisted of four values, and 15 park services were established and used to survey 38 landscape experts. As a result, services for improving the park's essential functions, such as contact with nature, relaxation, and exercise-walking, were deemed important. Services related to the environment and safety in response to climate change, such as the amelioration of pollution and heatwaves were also high. The importance of social integration services was relatively low, but it was considered an important service to when enhancing community participation. Future smart parks should enhance the health benefits of contact with nature rather than implementing excessive artificial facilities and technology. Additionally, smart technology will need to be applied based on users' needs while reflecting local characteristics. Efforts should be made to enhance user intimacy and improve the understanding of smart parks by strengthening public relations education.

The past, present and future of silkworm as a natural health food (천연 건강식품인 누에의 과거, 현재 그리고 미래)

  • Kim, Kee-Young;Koh, Young Ho
    • Food Science and Industry
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    • v.55 no.2
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    • pp.154-165
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    • 2022
  • Humans have been breeding the mulberry silkworm for the long period of time to obtain silk fabric and nutrient-rich pupae. Currently, silkworm larvae, pupae, and silk-Fibroin hydrolysates are registered as food raw materials, while silkworm feces and Bombyx batryticatus are registered as Korean traditional medicines. Among sericulture products, individually recognized health functional food ingredients include silk-protein acid-hydrolysates for immunity enhancement, Fibroin-hydrolysates for memory improvement, and freeze-dried 5th instar and 3rd-day-silkworm powder for lowering-blood sugar. Recently, HongJam produced by steaming and freeze-drying mature silkworms were reported to have various health-promoting effects such as preventing the onset of Alzheimer's disease and Parkinson's disease, enhancing gastro-intestinal functions, improving skin-whitening and hair growth, and extending healthspan. By consuming silkworm products with various health-promoting effects, it is possible to increase the healthspan of human beings, thereby reducing personal and national medical expenses, resulting in increasing the individual's happiness.

Analysis of Impacts of the Northeast Pacific Atmospheric Blocking and Contribution of Regional Transport to High-PM10 Haze Days in Korea (한국의 고농도 PM10 연무 사례일 발생에 대한 대기 블로킹의 영향과 장거리 수송 기여도 분석)

  • Jeong, Jae-Eun;Cho, Jae-Hee;Kim, Hak-Sung
    • Journal of the Korean earth science society
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    • v.43 no.1
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    • pp.77-90
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    • 2022
  • Despite the decreasing trend of anthropogenic emissions in East Asia in recent years, haze days still frequently occur in spring. Atmospheric blocking, which occurs frequently in the northeastern Pacific, leads to persistent changes in large-scale circulation and blocks westerly flow in the East Asian region. During March 2019, frequent warm and stagnant synoptic meteorological conditions over East Asia were accompanied 6-7 days later by the Alaskan atmospheric blocking. The Alaskan atmospheric blocking over the period of March 18-24, 2019 led to high particulate matter (PM10) severe haze days exceeding a daily average of 50 ㎍ m-3 over the period of March 25-28, 2019 in South Korea. Although the high-PM10 severe haze days were caused by warm and stagnant meteorological conditions, the regional contribution of anthropogenic emissions in eastern China was calculated to be 30-40% using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem). The major regional contributions of PM10 aerosols in the period of high-PM10 severe haze days were as follows: nitrates, 20-25%; sulphates, 10-15%; ammonium, 5-10%; and other inorganics, 15-20%. Ammonium nitrate generated via gas-to-aerosol conversion in a warm and stagnant atmosphere largely contributed to the regional transport of PM10 aerosols in the high-PM10 severe haze days in South Korea.

Evaluation of PM2.5 Exposure Contribution Using a Microenvironmental Model (국소환경 모델을 이용한 초미세먼지(PM2.5) 노출 기여율 평가)

  • Shin, Jihun;Choe, Yongtae;Kim, Dongjun;Min, Gihong;Woo, Jaemin;Kim, Dongjun;Shin, Junghyun;Cho, Mansu;Sung, Kyeonghwa;Lee, Jongdae;Yang, Wonho
    • Journal of Environmental Health Sciences
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    • v.48 no.2
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    • pp.59-65
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    • 2022
  • Background: Since people move through microenvironments rather than staying in one place, they may be exposed to both indoor and outdoor PM2.5 concentrations. Objectives: The aim of this study was to assess the exposure level of each sub-population group and evaluate the contribution rate of the major microenvironments. Methods: Exposure scenarios for sub-population groups were constructed on the basis of a 2019 Time-Use survey and the previous literature. A total of five population groups were classified and researchers wearing MicroPEM simulated monitoring PM2.5 exposure concentrations in real-time over three days. The exposure contribution for each microenvironment were evaluated by multiplying the inhalation rate and the PM2.5 exposure concentration levels. Results: Mean PM2.5 concentrations were 33.0 ㎍/m3 and 22.5 ㎍/m3 in Guro-gu and Wonju, respectively. When the exposure was calculated considering each inhalation rate and concentration, the home showed the highest exposure contribution rate for PM2.5. As for preschool children, it was 90.8% in Guro-gu, 94.1% in Wonju. For students it was 65.3% and 67.3%. For housewives it was 98.2% and 95.8%, and 59.5% and 91.7% for office workers. Both regions had higher exposure to PM2.5 among the elderly compared to other populations, and their PM2.5 exposure contribution rates were 98.3% and 94.1% at home for Guro-gu and Wonju, respectively. Conclusions: The exposure contribution rate could be dependent on time spent in microenvironments. Notably, the contribution rate of exposure to PM2.5 at home was the highest because most people spend the longest time at home. Therefore, microenvironments such as home with a higher contribution rate of exposure to PM2.5 could be managed to upgrade public health.