• Journal of Korean Society of Water and Wastewater
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• v.27 no.5
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• pp.603-610
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• 2013

According to industrialization, increased toxic chemicals discharge has been causing water pollution. Especially domestic sewage is a major source of water pollution. Sixty percent of the total wastewater discharged is domestic sewage. Self-purification capacity of rivers and streams is drastically reduced by the emission of domestic sewage, industrial wastewater and livestock wastewater. Although domestic sewage is managed by implementing standards and regulations, toxicity effect of domestic sewage to humans and the environment is not yet clearly understood. In this study, by using daphnia magna, the ecotoxicity of domestic swage was assessed. Cl, Cu, Pb, COD, T-N, DO, pH and residual chlorine were investigated as background concentrations. The experiments were conducted with water samples obtained from three local sewage treatment plants. The experiment results indicated that higher level of toxicity corresponds to the higher pollution concentrations. The higher level of combinations of background concentrations such as heavy metals leads to the worse ecotoxicity. Especially, the Cu concentration affects the TU value.

• Environmental Engineering Research
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• v.23 no.4
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• pp.397-405
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• 2018

As regulations governing the control of volatile organic compounds (VOCs) have become increasingly stringent in China, regenerative thermal oxidizers (RTOs) have been more frequently applied in medium- and high-concentration VOCs treatments. However, due to the lack of existing RTO-related research, experience remains a dominant factor for industrial application. This paper thus aimed to establish a model for industrial RTOs, using a transient simulation method and thermal equilibrium model to simulate the internal velocities and temperature distributions of an RTO across multiple cycles. A comparison showed an error of less than 5% between most correlating simulated and experimental measurement points, verifying that the simulation method was accurate. After verification, the velocity and temperature fields inside the RTO were simulated to study the uniformity of temperature and velocity within the packed beds: both fields displayed high uniformity after gas flowed through the honeycomb regenerator. The effects of air volume, VOCs concentrations, and valve switching times on the oxidation chamber temperature, RTO outlet temperature, and thermal efficiency (as well as their averages) were studied. The VOCs removal rate in this study was constantly above 98%, and the average thermal efficiency reached 90%.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.4
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• pp.406-415
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• 2018

Objective: The purpose of this study was to investigate the hazards of cosmetic ingredients in Korea. Methods: An Excel database of cosmetic ingredients was developed on a website(Korea Cosmetic Ingredient Dictionary) and used for a hazard assessment based on Tox-free, a database containing toxic information such as on carcinogens, mutagens or reproductive toxicants(CMRs) and endocrine disrupting chemicals(EDCs), as well as other regulated chemicals in Korea. Results: A total of 16,605 chemicals were registered with the cosmetic ingredient dictionary and 308 of them were identified as either CMRs or EDCs. CMRs included formaldehyde and nickel gluconate, and EDCs included parabens, benzophenon, styrene, and toluene. Reproductive toxicants such as xylene, zinc chloride, toluene, and formaldehyde were regulated by the Occupational Safety and Health Act and the Act on the Registration and Evaluation, etc. of Chemical Substances(the Chemical Control Act). Conclusions: Regulations on cosmetics components should be strengthened, and the right to know about cosmetics containing hazardous chemicals should be guaranteed.

• Journal of Korea Society of Waste Management
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• v.35 no.8
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• pp.709-720
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• 2018

Since the import ban of plastic waste in China has been enforced, plastic wastes were not properly collected and recycled in Korea. Hence, the management strategies for plastic waste in Korea should be improved by examining the regulations and policy in developed countries such as United States, Japan, EU and United Kingdom. The management strategy for the recycling cycle should be implemented to expand the labeling system of separation and discharge, reduce the consumption of plastic products, automate the separation and sorting method in recycling facilities, and improve the economical efficiency of the recycling cycle. The concept of residual waste (secondary waste) in the material flow analysis should be implemented to identify the shortage point in the plastic waste stream. Finally, the cooperation with international communities is required for a transboundary movement of plastic waste, which includes participation at the working group of international standards to recycle plastic waste.

• Applied Chemistry for Engineering
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• v.34 no.1
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• pp.75-79
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• 2023

The International Maritime Organization (IMO) Marine Environmental Protection Committee (MEPC) may adopt actions after completing impact assessments and reviewing results in accordance with the original strategy and impact assessment procedure (MEPC.1/Circ.885). The assessment of the impact of greenhouse gas (GHG) reduction measures is an important step in determining whether to implement GHG regulations. This study identifies and proposes improvements in the impact assessment procedure for future mid- and long-term measures. Improvements for future measures should start with a review of "the procedure for assessing impacts on states of candidate measures" and "the actual process of the comprehensive impact assessment for short-term measures in 2021." The procedural improvements were largely derived from the order and period of task performance, the clear definition of terms, and the review of task results through lessons learned, analysis, and expert workshops. The impact assessment of future mid- and long-term measures should be procedurally improved to ensure uniformity and consistency, which will provide objective results for Member States and industries to help smooth the adoption of measures.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.2
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• pp.86-94
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• 2023

Tonnage taxation has contributed to developing the Korean maritime industry through tax relief for shipping companies. The current tonnage taxation relies on the net tonnage as an earning-capacity indicator in a merchant ship. Although the tonnage tax accords with horizontal equity, it does not match vertical equity because of the different taxable capacities of an individual company. Nowadays, maritime transport uses a dedicated vessel, and each shipping freight embeds a different value of time. It means the tonnage taxation regime should consider the added value of each shipping freight. Meanwhile, as the environmental regulations led by the International Maritime Organization are being strengthened, the Korean merchant fleet must be eco-friendly soon after. This study explores the alternative to renewing tonnage taxation by utilizing the Greenship certification and considering the ability-to-pay principle. Because the Greenship certification scheme encourages shipping decarbonization, maritime transport by a certified ocean-going vessel comes to be treated as an activity for the green economy. Special taxation for the green economy may contribute to shipping sustainability and market competitiveness.

• Clean Technology
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• v.29 no.2
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• pp.145-150
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• 2023

Tele-metering systems have been useful tools for managing domestic wastewater treatment plants (WWTP) over the last decade. They mostly generate water quality data for discharged water to ensure that it complies with mandatory regulations and they may be able to produce every operation parameter and additional measurements in the near future. A sub-big data group, comprised of about 150,000 data points from four domestic WWTPs, was ready to be classified and also analyzed to optimize the WWTP process. We used the Statistical Product and Service Solutions (SPSS) 25 package in order to statistically treat the data with linear regression and correlation analysis. The major independent variables for analysis were water temperature, sludge recycle rate, electricity used, and water quality of the influent while the dependent variables representing the water quality of the effluent included the total nitrogen, which is the most emphasized index for discharged flow in plants. The water temperature and consumed electricity showed a strong correlation with the total nitrogen but the other indices' mutual correlations with other variables were found to be fuzzy due to the large errors involved. In addition, a multilayer perceptron analysis method was applied to TMS data along with root mean square error (RMSE) analysis. This study showed that the RMSE in the SS, T-N, and TOC predictions were in the range of 10% to 20%.

• International conference on construction engineering and project management
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• 2024.07a
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• pp.917-924
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• 2024

Despite various government and institutional movements to promote implementation of smart construction, the utilization of smart technologies in the construction industry is still low compared to other industries. To take a systemic look at the impediments in the implementation of smart construction, this study identifies and analyzes the challenging factors of smart construction within the Korean construction industry. Through content analysis of relevant literature, including official documents, research reports, databases, 19 challenging factors have been identified. The intricate relationships among these challenging factors have been examined based on a hierarchy structure established by using the Interpretive Structural Modeling (ISM) approach. Furthermore, factors are classified into four distinct clusters by using the MICMAC analysis: driving factors, dependent factors, autonomous factors, and linkage factors. This classification delineates the interrelationships among the challenging factors and identifies the key factors that drive the system, which is different from that in traditional studies where the relative importance is generally given between factors. The findings will provide crucial information for policy designers and top-level authorities, indicating which challenging factors to prioritize limited resources and efforts. It will aid in formulating effective policies, standards, and regulations to foster the implementation of smart construction in the Korean construction industry.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.1
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• pp.74-92
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• 2000

This study was performed to evaluate the working conditions In construction workers through measurements of working environments and to improve the working conditions and to design the appropriate environmental and health management system. The results of measurement for working environments in construction work are as following: 1. The excess rate of noise and dust concentration in express highway construction, road construction, building construction and interior painting was 28.6% and 24.5% respectively. 2. The excess rate of mixed organic solvents concentration in interior painting was 39.3%. 3. The chain type bulldozer has the highest level of vibration; the excess rate was 85.7%, and among the vibration instruments, the level of left hand's vibration of all vibrators exceeded the criterion and in the case of drilling all the level of vibration exceeded the criterion in both hands. On the basis of the results in this research the environmental and health management system for construction workers must be considered. Therefore, it is necessary to be introduced the special medical examination and measurement of working environments in construction industry. In defining "the working place" of Article 39 of Enforcement regulations of industrial safety and health act, the word "indoors" should be deleted. Then the eligible industry for measurement of working environment must be extended. And it is also necessary for construction industry to be performed group health management service by agencies such as other manufacturing industry.

• Journal of Environmental Health Sciences
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• v.37 no.4
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• pp.323-331
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• 2011

Objective: This study aimed to examine the level of risk perception related to pesticide contamination of food products and associated sociodemographic factors, as well as investigate the association with environmental pollution preventive behaviors. Methods: Based on data from Social Survey conducted in 2008 among a nationally representative sample of the population 15 years or older, we estimated proportions and 95% confidence intervals of the risk perception of pesticide contamination of food products. Logistic regression analyses were used to analyze the effects of sociodemographic status on risk perception. Results: Among respondents, those who feel anxious about the risks of pesticide contamination of domestic food products accounted for 40.4%, whereas the proportion rose to 87.0% with imported food products. These numbers showed that levels of anxiety about the pesticide contamination of imported food products were ranked at the top, and those for domestic products were at the bottom of the list of all environmental pollutants examined in the survey. Significantly related factors to anxiety about pesticide contamination of food products included women, the 40-50 age group, university graduates, married, non-manual employment, having school-aged children, and owning one's own home. The population attempting to prevent environmental pollution showed higher levels of anxiety about pesticide contamination of food products than did those who were not taking such steps. Conclusion: Compared to other forms of environmental pollution, Koreans show the highest levels of anxiety about pesticide contamination of imported food products. Therefore, it is necessary to establish appropriate regulations and transparent risk communication with the public about the safety of imported food.