• Journal of ILASS-Korea
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• v.24 no.4
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• pp.178-184
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• 2019

Diesel engines have the advantages of higher thermal efficiency and lower CO2 emissions than gasoline engines, but have the disadvantages that particulate matter (PM) and nitrogen oxides (NOx) emissions are greater than those of gasoline engines. In particular, nitrogen oxides (NOx) emitted from diesel engines generates secondary ultrafine dust (PM2.5) through photochemical reactions in the atmosphere, which is fatal to humans. In order to reduce nitrogen oxides (NOx), pre-treatment systems such as EGR, post-treatment systems such as LNT and Urea SCR have been actively studied. The Urea SCR consists of an injection device injecting urea agent and a catalytic device for reducing nitrogen oxides (NOx). The nitrogen oxide (NOx) reduction performance varies greatly depending on the urea uniformity in the exhaust pipe. In this study, spray characteristics according to the spray hole structure were confirmed, and the influence of spray uniformity on spray characteristics was studied through engine evaluation.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.05a
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• pp.55-56
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• 2018

In order to construct an efficient monitoring system for major port cities in Korea, the first step to build and manage related laws and institutional infrastructure with strengthen the cooperation of the relevant agencies, regional port authorities, and port corporations. Second, for the management of air pollutants emitted by ports, a management system should be established through systematic inventory source inventory and real-time monitoring system. Third, active countermeasures should be established to reduce the emission of air pollutants by sources such as ships, harbor equipment, and trucks. This will improve the air quality of major port cities and move them to clean port cities.

• Journal of Korea Society of Waste Management
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• v.35 no.7
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• pp.647-652
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• 2018

The emission of nitrogen oxides has a great environmental impact. It leads to Los Angeles type smog, and it recently has attracted attention as a source of ultrafine dust. The main sources of nitrogen oxides are internal combustion engines and industrial boilers. These emission sources are processes that are essential for human industrial activities, so the regulation of original use is impossible. Therefore, special control methods should be applied to reduce NOx emissions into the atmosphere. In this study, we investigated how the supply of ER and urea influences the removal of nitrogen oxides from SRF combustion boilers. Experimental results show that the removal efficiency of nitrogen oxides can be up to 80% under the conditions of ER 2.0 and a urea feed of 0.5 LPM.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.536-539
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• 2018

In this paper, we propose a system that analyzes environment information by using deep learning and then provides a suitable environment for users by predicting environmental information change. As the level of living improves, interest in improving the quality of life is increasing. In particular, as the air quality deteriorated due to the recent occurrence of dust, smog, fine dust, and ultrafine dust, the indoor air quality as well as the outdoor air became a serious problem. The increase of indoor pollution due to the lack of ventilation and the use of chemicals is a serious problem for modern people who have a lot of indoor living. In order to solve this indoor air pollution, a system has been proposed that measures the state of air quality through sensors and maintains proper temperature and humidity. However, existing system has a difficulty to apply most of the atmospheric environment information to various users depending on sensors only. The system proposed in this paper predicts the indoor environment by analyzing the indoor pollution information collected through the sensor using the deep learning. Then, the predicted indoor environment is modeled and learned in this system, and the environment suitable for the user is suggested. Afterwards, the system receives feedback from the user and repeats the process of re-learning the proposed environment so that it can create the optimal environment for the user.

• Journal of Korea Port Economic Association
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• v.38 no.1
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• pp.129-142
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• 2022

In the past, interest in air pollution was concentrated on greenhouse gases, but in recent years, interest in fine dust has been increasing. The media and environmental organizations continue to emphasize air pollution caused by fine dust. The awareness of fine dust is increasing, and air pollution generated at ports is analyzed to be serious as a domestic factor excluding foreign inflows. Recognizing this, in order to reduce air pollution generated at ports, special laws on improving air quality, such as port areas, have been enacted in Korea, and attempts are being made to curb air pollution caused by ports. In this law, it is a policy that regulates air pollutants generated not only by ships but also throughout ports such as vehicles and unloading machines, and representative are ECA, VSR, and AMP. This study attempted to analyze the effects of these eco-friendly policies at Incheon Port. First of all, a study was conducted to calculate emissions assuming that there was no policy, analyze each policy, and finally calculate and compare actual emissions reflecting all policies. The methodology presented by the European Environmental Administration and the U.S. Environmental Protection Agency was used, and pollutants to be analyzed were analyzed for sulfur oxides (SO_X), carbon monoxide (CO), nitrogen oxides (NO_X), total floating substances (TSP), fine dust and ultrafine dust (PM₁₀, PM_2.5) and ammonia (NH₃). As a result of the analysis, it was analyzed that the actual emission reflecting all policies was about 4,097 tons/year, which had an emission reduction effect of about 760 tons/year compared to about 4,857 tons/year when the policy was not reflected. When the effects of each policy were analyzed individually, it was found that ECA 4,111 tons/year, VSR 4,854 tons/year, and AMP 4,843 tons of air pollutant emissions occurred The results of this study can be used as basic data and evidence for policy establishment related to the atmospheric environment at Incheon Port.

• Safety and Health at Work
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• v.3 no.1
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• pp.58-66
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• 2012

Objectives: The purpose of this study was to review clinical characteristics and working environments of sudden cardiac death (SCD) cases associated with a tire manufacturer in Korea, and review possible occupational risk factors for cardiovascular disease including nanoparticles (ultrafine particles, UFPs). Methods: We reviewed (i) the clinical course of SCD cases and (ii) occupational and non-occupational risk factors including chemicals, the physical work environment, and job characteristics. Results: Possible occupational factors were chemicals, UFPs of rubber fume, a hot environment, shift work, overworking, and noise exposure. The mean diameter of rubber fume (63-73 nm) was (larger than diesel exhaust [12 nm] and outdoor dust [50 nm]). The concentration of carbon disulfide, carbon monoxide and styrene were lower than the limit of detection. Five SCD cases were exposed to shift work and overworking. Most of the cases had several non-occupational factors such as hypertension, overweight and smoking. Conclusion: The diameter of rubber fume was larger than outdoor and the diesel exhaust, the most well known particulate having a causal relationship with cardiovascular disease. The possibility of a causal relation between UFPs of rubber fume and SCD was not supported in this study. However, it is necessary to continue studying the relationship between large sized UFPs and SCD.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.513-525
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• 2020

Purpose: The purpose of this study is to analyze the characteristics of local factors affecting number of tuberculosis death by urban and rural areas. Method: The Partial Least Square(PLS) Regression analysis was used to solve the problem of multicollinearity and number of samples. Result: As a result of analysis, The number of tuberculosis deaths in urban and rural areas is about three times as large. As a result of analysis about Regional Characteristics Factor, In general, children, elderly people, and economically vulnerable populations are more likely to be exposed to tuberculosis. In differential results, it shows that environmental factors such as ultrafine dust and sulfur dioxide have a significant impact on the number of tuberculosis deaths in urban areas and social factors such as depression experience rate in rural areas. Conclusion: The Tuberculosis prevention and management policies that reflect the characteristics of urban and rural areas are needed in the future.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.4
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• pp.221-228
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• 2017

We proposed a novel method to remove PM2.5 dusts without HEPA filters aiming at applications in kitchens or enclosed work spaces generating PM2.5 at high concentrations. Many workers are exposed to PM2.5 owing to lack of air purification because the high replacement costs of HEPA filters make their application impractical. A key idea is to use the condensational growth of nanoparticles. Once particles grow to the size of a few micrometers, it is much easier to remove them because of their increased inertia. We developed and tested a prototype consisting of an air saturator (equipped with water spray nozzles), a condenser in which humid air was cooled down to make the particles grow, and a multi-impactor assembly for collecting the grown particles.

• Toxicological Research
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• v.33 no.4
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• pp.305-313
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• 2017

Accumulating epidemiological evidence indicates that exposure to fine air pollution particles (APPs) is associated with a variety of adverse health effects. However, the exact physiochemical properties and biological toxicities of fine APPs are still not well characterized. We collected four types of fine particle (FP) (diesel exhaust particles [DEPs], natural organic combustion [NOC] ash, synthetic organic combustion [SOC] ash, and yellow sand dust [YSD]) and investigated their physicochemical properties and in vitro biological toxicity. DEPs were almost entirely composed of ultrafine particles (UFPs), while the NOC, SOC, and YSD particles were a mixture of UFPs and FPs. The main elements in the DEPs, NOC ash, SOC ash, and YSD were black carbon, silicon, black carbon, and silicon, respectively. DEPs exhibited dose-dependent mutagenicity even at a low dose in Salmonella typhimurium TA 98 and 100 strains in an Ames test for genotoxicity. However, NOC, SOC, and YSD particles did not show any mutagenicity at high doses. The neutral red uptake assay to test cell viability revealed that DEPs showed dose-dependent potent cytotoxicity even at a low concentration. The toxicity of DEPs was relatively higher than that of NOC, SOC, and YSD particles. Therefore, these results indicate that among the four FPs, DEPs showed the highest in vitro biological toxicity. Additional comprehensive research studies such as chemical analysis and in vivo acute and chronic inhalation toxicity tests are necessary to determine and clarify the effects of this air contaminant on human health.

• Korean Journal of Environmental Agriculture
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• v.40 no.3
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• pp.149-160
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• 2021

BACKGROUND: Concerns have been raised about the impact of recent high concentrations of fine dust on human health. Ammonia(NH₃) reacts with sulfur oxides and nitrogen compounds in the atmosphere to form ultrafine ammonium sulfate and ammonium nitrate (PM2.5). There is a growing need for accurate estimates of the amount of ammonia emitted during agricultural production. Therefore, in this study, ammonia emissions generated from the cultivation of leafy perilla in plastic houses were determined. METHODS AND RESULTS: Cow manure compost, swine manure compost, and poultry manure compost each at 34.6 ton ha^-1, the amount commonly used by farmers in the field, was sprayed on the soil surface. Just after spraying cow manure compost, swine manure compost, and poultry manure compost, the ammonia was periodically measured and analyzed to be 22.5 kg ha^-1, 22.8 kg ha^-1, and 85.2 kg ha^-1, respectively. The emission factors were estimated at 70.0 kg-NH₃ ton-N, 62.8 kg-NH₃ ton-N, and 234.1 kg-NH₃ ton-N, respectively. Most ammonia was released in the two weeks after application of the compost and then the amount released gradually decreased. CONCLUSION: Therefore, it is necessary to improve the emission factor through a study on the estimation of ammonia emission by type of livestock manure and major farming types such as rice fields and uplands, and to update data on the production, distribution, and sales of livestock manure.