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Kriging of Daily PM10 Concentration from the Air Korea Stations Nationwide and the Accuracy Assessment (베리오그램 최적화 기반의 정규크리깅을 이용한 전국 에어코리아 PM10 자료의 일평균 격자지도화 및 내삽정확도 검증)

  • Jeong, Yemin;Cho, Subin;Youn, Youjeong;Kim, Seoyeon;Kim, Geunah;Kang, Jonggu;Lee, Dalgeun;Chung, Euk;Lee, Yangwon
    • Korean Journal of Remote Sensing
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    • v.37 no.3
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    • pp.379-394
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    • 2021
  • Air pollution data in South Korea is provided on a real-time basis by Air Korea stations since 2005. Previous studies have shown the feasibility of gridding air pollution data, but they were confined to a few cities. This paper examines the creation of nationwide gridded maps for PM10 concentration using 333 Air Korea stations with variogram optimization and ordinary kriging. The accuracy of the spatial interpolation was evaluated by various sampling schemes to avoid a too dense or too sparse distribution of the validation points. Using the 114,745 matchups, a four-round blind test was conducted by extracting random validation points for every 365 days in 2019. The overall accuracy was stably high with the MAE of 5.697 ㎍/m3 and the CC of 0.947. Approximately 1,500 cases for high PM10 concentration also showed a result with the MAE of about 12 ㎍/m3 and the CC over 0.87, which means that the proposed method was effective and applicable to various situations. The gridded maps for daily PM10 concentration at the resolution of 0.05° also showed a reasonable spatial distribution, which can be used as an input variable for a gridded prediction of tomorrow's PM10 concentration.

Global Ocean Data Assimilation and Prediction System in KMA: Description and Assessment (기상청 전지구 해양자료동화시스템(GODAPS): 개요 및 검증)

  • Chang, Pil-Hun;Hwang, Seung-On;Choo, Sung-Ho;Lee, Johan;Lee, Sang-Min;Boo, Kyung-On
    • Atmosphere
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    • v.31 no.2
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    • pp.229-240
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    • 2021
  • The Global Ocean Data Assimilation and Prediction System (GODAPS) in operation at the KMA (Korea Meteorological Administration) is introduced. GODAPS consists of ocean model, ice model, and 3-d variational ocean data assimilation system. GODAPS assimilates conventional and satellite observations for sea surface temperature and height, observations of sea-ice concentration, as well as temperature and salinity profiles for the ocean using a 24-hour data assimilation window. It finally produces ocean analysis fields with a resolution of 0.25 ORCA (tripolar) grid and 75-layer in depth. This analysis is used for providing a boundary condition for the atmospheric model of the KMA Global Seasonal Forecasting System version 5 (GloSea5) in addition to monitoring on the global ocean and ice. For the purpose of evaluating the quality of ocean analysis produced by GODAPS, a one-year data assimilation experiment was performed. Assimilation of global observing system in GODAPS results in producing improved analysis and forecast fields with reduced error in terms of RMSE of innovation and analysis increment. In addition, comparison with an unassimilated experiment shows a mostly positive impact, especially over the region with large oceanic variability.

Air-staging Effect for NOx Reduction in Circulating Fluidized Bed Combustion of Domestic Unused Biomass (국내 미이용 바이오매스 순환유동층 연소에서 NOx 저감을 위한 air-staging 효과)

  • Yoon, Sang-Hee;Beak, Geon-Uk;Moon, Ji-Hong;Jo, Sung-Ho;Park, Sung-Jin;Kim, Jae-Young;Seo, Myung-Won;Yoon, Sang-Jun;Yoon, Sung-Min;Lee, Jae-Goo;Kim, Joo-Sik;Mun, Tae-Young
    • Korean Chemical Engineering Research
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    • v.59 no.1
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    • pp.127-137
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    • 2021
  • Air emission charge for nitrogen oxide as a precursor of fine dust has been introduced and implemented within the country from 2020. Therefore, the development of economical combustion technology for NOx reduction has got more needed urgently. This study investigated the air-staging effect as a way to reduce the NOx during combustion of domestic unused forest biomass, recently possible to secure REC (Renewable Energy Certification) as a substitute for overseas wood pellets in a 0.1 MWth circulating fluidized bed combustion test-rig. Operating conditions were comparison with and without air-staging, the supply position of tertiary air (6.4 m, 8.1 m, 9.4 m in the combustor) and variation of air-staging ratio (Primary air:Secondary air:Tertiary air=91%:9%:0%, 82%:9%:9%, 73%:9%:18%). NO and CO concentrations in flue gas, profiles of temperature and pressure at the height of the combustion, unburned carbon in sampled fly ash and combustion efficiency on operating conditions were evaluated. As notable results, NO concentration with air-staging application under tertiary air supply at 9.4 m in the combustor reduced 100.7 ppm compared to 148.8 ppm without air-staging while, CO concentration increased from 52.2 ppm without air-staging to 99.8 ppm with air-staging. However, among air-staging runs, when tertiary air supply amount at 6.4 m in the combustor increased by air-staging ratio (Primary air:Secondary air:Tertiary air=73%:9%:18%), NO and CO concentrations decreased the lowest 90.8 ppm and 66.1 ppm, respectively. Furthermore, combustion efficiency at this condition was improved to 99.3%, higher than that (98.3%) of run without air-staging.

Evaluation Method of Cosmetics for the Effect of Fine Dust Adhesion Prevention Using Floating Chamber (부유챔버를 이용한 화장품의 미세먼지 부착방지 효과 평가법)

  • Kim, Woncheol;Kim, Han Jo;Boo, Yong Chool;Koh, Jae Sook;Baek, Ji Hwoon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.46 no.4
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    • pp.319-327
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    • 2020
  • Particulate matters (PM) are small particulate pollution that decrease the function of skin barrier, which causes inflammatory skin diseases and extrinsic aging. In this study, we evaluated the effect of preventing the adherence of PMs from several cosmetic products applied to human skin using iron oxide black. The PM floating chamber consists of skin exposure area, PM inlet, floating power device, and an outlet so that PM can be naturally attached to the skin while floating in the chamber. The change in skin brightness according to the floating concentration of alternative fine dust was checked to confirm the optimal floating concentration conditions. The intensity difference (before-after intensity, Δ) before and after adhesion of iron oxide black was proportional to the amount of PM adhered. The anti-adherence effect of iron oxide black on five cosmetic products were evaluated through 20 each subjects by comparing the amount of iron oxide black adhered on the control and treatment. The difference in brightness before and after the iron oxide black attached to the skin was calculated and compared with the control group(p < 0.05). When over 150 mg of iron oxide black was adhered on the skin, the interference of intensity was low and clearly showed the skin adhered pattern. According to the application of the five cosmetics, the intensity difference was significantly lower than the control group. This means that depending on the product, it prevented the attachment of iron oxide black. This study is a safe and useful method to confirm the prevention of PM skin adherence. In conclusion, cosmetics can prevent the adherence of PM on the skin according to the formulation or ingredients characteristics.

CFD Simulation of Changesin NOX Distribution according to an Urban Renewal Project (CFD 모델을 이용한 도시 재정비 사업에 의한 NOX 분포 변화 모의)

  • Kim, Ji-Hyun;Kim, Yeon-Uk;Do, Heon-Seok;Kwak, Kyung-Hwan
    • Journal of Environmental Impact Assessment
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    • v.30 no.3
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    • pp.141-154
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    • 2021
  • In this study, the effect of the restoration of Yaksa stream and the construction of an apartment complex by the urban renewal project in the Yaksa district of Chuncheon on air quality in the surrounding area was evaluated using computational fluid dynamics (CFD) model simulations. In orderto compare the impact of the project, wind and pollutant concentration fields were simulated using topographic data in 2011 and 2017, which stand for the periods before and after the urban renewal project, respectively. In the numerical experiments, the scenarios were set to analyze the effect of the construction of the apartment complex and the effect of stream restoration. Wind direction and wind speed data obtained from the Chuncheon Automated Synoptic Observing System (ASOS) were used as the inflow boundary conditions, and the simulation results were weighted according to the frequencies of the eight-directional inflow wind directions. The changes in wind speed and NOX concentration distribution according to the changes in building and terrain between scenarios were compared. As a result, the concentration of NOX emitted from the surrounding roads increased by the construction of the apartment complex, and the magnitude of the increase was reduced as the result of including the effect of stream restoration. The concentration of NOX decreased around the restored stream, while the concentration increased significantly around the constructed apartment complex. The increase in the concentration of NOX around the apartment complex was more pronounced in the place located in the rear of the wind direction to the apartment complex, and the effect remains up to the height of the building. In conclusion, it was confirmed that the relative arrangement of apartment complex construction and stream restoration in relation to the main wind direction of the target area was one of the major factors in determining the surrounding air quality.

The Effect of Carbon Dioxide Leaked from Geological Storage Site on Soil Fertility: A Study on Artificial Leakage (지중 저장지로부터 누출된 이산화탄소가 토양 비옥도에 미치는 영향: 인위 누출 연구)

  • Baek, Seung Han;Lee, Sang-Woo;Lee, Woo-Chun;Yun, Seong-Taek;Kim, Soon-Oh
    • Economic and Environmental Geology
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    • v.54 no.4
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    • pp.409-425
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    • 2021
  • Carbon dioxide has been known to be a typical greenhouse gas causing global warming, and a number of efforts have been proposed to reduce its concentration in the atmosphere. Among them, carbon dioxide capture and storage (CCS) has been taken into great account to accomplish the target reduction of carbon dioxide. In order to commercialize the CCS, its safety should be secured. In particular, if the stored carbon dioxide is leaked in the arable land, serious problems could come up in terms of crop growth. This study was conducted to investigate the effect of carbon dioxide leaked from storage sites on soil fertility. The leakage of carbon dioxide was simulated using the facility of its artificial injection into soils in the laboratory. Several soil chemical properties, such as pH, cation exchange capacity, electrical conductivity, the concentrations of exchangeable cations, nitrogen (N) (total-N, nitrate-N, and ammonia-N), phosphorus (P) (total-P and available-P), sulfur (S) (total-S and available-S), available-boron (B), and the contents of soil organic matter, were monitored as indicators of soil fertility during the period of artificial injection of carbon dioxide. Two kinds of soils, such as non-cultivated and cultivated soils, were compared in the artificial injection tests, and the latter included maize- and soybean-cultivated soils. The non-cultivated soil (NCS) was sandy soil of 42.6% porosity, the maize-cultivated soil (MCS) and soybean-cultivated soil (SCS) were loamy sand having 46.8% and 48.0% of porosities, respectively. The artificial injection facility had six columns: one was for the control without carbon dioxide injection, and the other five columns were used for the injections tests. Total injection periods for NCS and MCS/SCS were 60 and 70 days, respectively, and artificial rainfall events were simulated using one pore volume after the 12-day injection for the NCS and the 14-day injection for the MCS/SCS. After each rainfall event, the soil fertility indicators were measured for soil and leachate solution, and they were compared before and after the injection of carbon dioxide. The results indicate that the residual concentrations of exchangeable cations, total-N, total-P, the content of soil organic matter, and electrical conductivity were not likely to be affected by the injection of carbon dioxide. However, the residual concentrations of nitrate-N, ammonia-N, available-P, available-S, and available-B tended to decrease after the carbon dioxide injection, indicating that soil fertility might be reduced. Meanwhile, soil pH did not seem to be influenced due to the buffering capacity of soils, but it is speculated that a long-term leakage of carbon dioxide might bring about soil acidification.

A study on the effect of startup entrepreneurs' experience of industry-university cooperation through incubator organizations on organizational learning capability and innovation performance (벤처기업 창업가의 배태조직과 산학협력 경험이 조직학습역량과 혁신성과에 미치는 영향)

  • Kim, Deokyong;Bae, Sung Joo
    • Journal of Technology Innovation
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    • v.30 no.2
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    • pp.29-58
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    • 2022
  • Startups lack resources and manpower to build internal capabilities to strengthen market competitiveness; external cooperation such as joint research and networking plays is important. In this study, we analyzed the effect of startups' industry-university cooperation on organizational learning capability and innovation performance. Empirical results demonstrate the mechanism by which government R&D investment strengthens organizational learning capability and creates innovative results by promoting cooperation between startups and universities. First, industry-university cooperation strengthened organizational learning capability. An empirical analysis shows that startups increase internal capabilities through external cooperation. Second, startups' organizational learning capability had a significant effect on innovation performance. We analyze how organizations with high learning capabilities positively develop corporate innovation performance by having a culture of discovery and sharing new ideas. Finally, industry-university cooperation had different effects on organizational learning capability and innovation performance according to the previous experiences of startup founders. In particular, small- and medium-sized (startup) businesses and individual-based experience groups positively affected the creation of organizational learning capabilities and innovation performance through industry-university cooperation. Small- and medium-sized businesses and individual founders have a relatively small cooperative network with the outside world compared to founders of large companies, universities, and research institutes; therefore, they strengthen organizational learning capabilities through cooperation with universities. This study demonstrates that government should create policy inducements for cooperation with universities to maximize the R&D performance of startups. Criticism exists that lending support to startups and universities will hinder innovation performance; nevertheless, government investment plays a role in expanding intangible resources such as accumulating technologies, fostering high-quality human resources, and strengthening innovation networks. Therefore, the government should appropriately utilize the its authority to strengthen investment strategies for startup growth.

Current status and future of insect smart factory farm using ICT technology (ICT기술을 활용한 곤충스마트팩토리팜의 현황과 미래)

  • Seok, Young-Seek
    • Food Science and Industry
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    • v.55 no.2
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    • pp.188-202
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    • 2022
  • In the insect industry, as the scope of application of insects is expanded from pet insects and natural enemies to feed, edible and medicinal insects, the demand for quality control of insect raw materials is increasing, and interest in securing the safety of insect products is increasing. In the process of expanding the industrial scale, controlling the temperature and humidity and air quality in the insect breeding room and preventing the spread of pathogens and other pollutants are important success factors. It requires a controlled environment under the operating system. European commercial insect breeding facilities have attracted considerable investor interest, and insect companies are building large-scale production facilities, which became possible after the EU approved the use of insect protein as feedstock for fish farming in July 2017. Other fields, such as food and medicine, have also accelerated the application of cutting-edge technology. In the future, the global insect industry will purchase eggs or small larvae from suppliers and a system that focuses on the larval fattening, i.e., production raw material, until the insects mature, and a system that handles the entire production process from egg laying, harvesting, and initial pre-treatment of larvae., increasingly subdivided into large-scale production systems that cover all stages of insect larvae production and further processing steps such as milling, fat removal and protein or fat fractionation. In Korea, research and development of insect smart factory farms using artificial intelligence and ICT is accelerating, so insects can be used as carbon-free materials in secondary industries such as natural plastics or natural molding materials as well as existing feed and food. A Korean-style customized breeding system for shortening the breeding period or enhancing functionality is expected to be developed soon.

Ecological Characteristics and Changes of Quercus mongolica Community in Namsan (Mt.), Seoul (서울시 남산 신갈나무림 생태계 특성과 변화 연구)

  • Han, Bong-Ho;Park, Seok-Cheol;Kim, Jong-Yup;Kwak, Jeong-In
    • Journal of the Korean Institute of Landscape Architecture
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    • v.50 no.2
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    • pp.41-63
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    • 2022
  • The purpose of this study is to secure objective and precise data through ecosystem monitoring, to reveal ecological characteristics through comparison and analysis with past survey data, and to accumulate basic data for diagnosing the current situation and predicting changes in the ecosystem. The target site is the 'Quercus mongolica forest on the Buksa-myeon of Namsan', which was designated as an Ecological Landscape Conservation Area (ELCA) of Seoul in July 2006. The research contents are analysis of soil environment change (1986~2016), change of actual vegetation (1978~2016), and change of plant community structure (1994~2016). A total of 8 fixed surveys (400~1,200m2) were established in 1994 and 2000. Analysis items are importance value, species and population, and Shannon's species diversity. The soil environment of Namsan is acidic (pH 4.40 in 2016), which is expected to have a negative impact on tree growth and vegetation structure due to its low capacity for exchangeable cations. Quercus mongolica forest in Namsan is mainly distributed on the northern slopes. The actual vegetation area changed from 49.4% in 1978 → 80.7% in 1986 → 82.4% in 2000 → 88.3% in 2005 → 88.3% in 2009 → 70.3% in 2016. In 2016, the forest decreased by 18% compared to 2009. While there was increased growth of Quercus mongolica in the tree layer from 2009 to 2016, the overall decline in vegetation area was due to logging and fumigation management following the spread of oak wilt in 2012. As for the changes in the plant community structure, Quercus mongolica of the tree layer was damaged by oak wilt, and the potential vegetation that can form the next generation was ambiguous. In the subtree layer, the force of urbanization tree species such as Styrax japonicus, Sorbus alnifolia, and Acer palmatum. was maintained or increased. In the shrub layer, the number of trees and species increased significantly due to the open tree crown, and accordingly, the species diversity of Shannon for woody plants also increased. In Quercus mongolica forest of Namsan, various ecological changes are occurring due to the effects of urban environments such as air pollution and acid rain, the limitation of Quercus mongolica pure forest due to oak wilt, and the introduction of exotic species, thus, it is necessary to establish a management plan through continuous monitoring.

Effect of Strategic Orientation on Information Technology Competency and Corporate Performance in Small and Medium-Sized Enterprises(SMEs) (중소기업의 전략적 지향성이 정보기술역량과 기업성과에 미치는 영향)

  • Yang, Hee-Jong;Jang, Gil-Sang
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.4
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    • pp.693-704
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    • 2021
  • This study empirically verified the effect of strategic orientation on information technology(IT) competency and corporate performance for organizational members engaged in small and medium-sized enterprises (SMEs). In the research model proposed in this study, strategic orientation affects corporate performance, and IT competency is used as a mediating variable in this process. For this study, a survey was conducted on organizational members working in small and medium-sized manufacturers located in Ulsan Metropolitan City. A total of 320 questionnaires were distributed, and 277 copies were used in this study. The collected data were statistically analyzed using SPSS 24.0. The research results are as follows: First, customer orientation, market orientation, and technology orientation of strategic orientation were found to have a positive (+) effect on both information technology knowledge and information technology operation of IT competency. And it was found that both customer orientation and technology orientation of strategic orientation only affects the information technology infrastructure of IT competency. Second, it was found that customer orientation and technology orientation of strategic orientation had a positive (+) effect on corporate performance, but market orientation had no effect on corporate performance. Third, it was found that information technology knowledge, information technology operation, and information technology infrastructure of IT competency had a positive (+) effect on corporate performance. Fourth, as a result of examining the mediating effect of information technology competency between strategic orientation and corporate performance, information technology knowledge, information technology operation, and information technology infrastructure of IT capability were found to have a partial mediating effect between customer orientation and technology orientation of strategic orientation and corporate performance. These research results suggest that in today's fourth industrial revolution era, customer-oriented and technology-oriented management strategies should be established to improve the competitive advantage and performance of small and medium-sized enterprises(SMEs) in the supply chain with large enterprises, and at the same time information technology capabilities such as information technology knowledge, information technology operation, and information technology infrastructure should be strengthened.