• Journal of Environmental Impact Assessment
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• v.23 no.2
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• pp.75-87
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• 2014

In order to analyze environmental impact of livestock manure and organic fertilizers, this study investigated livestock-breeding and pollution loads, the status of individual and public livestock manure treatment facilities, and the status of production, supply and components of compost and liquid fertilizers in the Nonsan area. Also, on a trial basis, this study investigated the life cycle of the environmental impact of livestock manure and its organic fertilizers on stream, groundwater, and agricultural soil. The results are as follows. Firstly, were detected the range of $0.13{\sim}1.32{\mu}g/L$ of As, $0.004{\sim}0.467{\mu}g/L$ of Cd and $0.5{\sim}9.2{\mu}g/L$ of Pb as a harmful substances which show lower concentrations than person preservation criteria of water qualities and aquatic ecosystem. However, it is not clear that heavy metals affect environment such as stream, groundwater and agricultural soil. Secondly, this influence could change according to investigation time and treatment efficiency. As were detected large amounts of persistent organic pollutants(e.g. $14.24{\sim}38.47{\mu}g/L$ of acetylsalicylic acid, $1.17{\sim}2.96{\mu}g/L$ of sulfamethazine, and $2.25{\sim}174.09{\mu}g/L$ of sulfathiazole) in effluent from livestock farms and small amounts of sulfathiazole($ND{\sim}1.63{\mu}g/L$) in the stream, it is necessary to monitor POPs at individual and public livestock manure treatment facilities. However, significant environmental impact did not appear at groundwater and agricultural soil in the test area supplied with liquid fertilizers. These results could be applied to investigate the environmental impact of livestock manure through a comprehensive livestock manure management information system.

• Journal of the Korean Institute of Gas
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• v.19 no.3
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• pp.1-8
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• 2015

In this study, we performed risk assessment of chloroprene by hazard evaluation and workplace investigation. The chemical is used to manufacture of shoes, tires, adhesives, and classified as IARC category 2B (possibly carcinogenic to humans) and target organ systemic toxicity. It is used about 1,300 tons per year in 27 sites. It was calculated the risk of carcinogenesis with chloroprene by Monte-carlo simulation that the averages are 2,199 and 26,404 in each case of working less than 15 minutes per day with local exhaust ventilation and over 4 hours per day without local exhaust ventilation. The risk of target organ systemic toxicity are 4.10 and 169.06 with high correlation with working time to be longer and with ventilation system. Therefore, it is recommended that the local exhaust ventilation and respirators to prevent occupational cancer and target organ systemic toxicity with chloroprene. Especially it is determined that there is a need to strengthen the workplace exposure limit (TWA 10 ppm) in Korea since it is managed with TWA less than 5 ppm ($18mg/m^3$) by the United States Occupational Safety and Health Administration (OSHA) as well as it has carcinogenicity, reproductive toxicity.

• Journal of Environmental Impact Assessment
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• v.24 no.4
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• pp.332-343
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• 2015

It would be the most effective way to have government take care of social problems and hazardous material danger due to odor. It is also well known that odor acceptance and their willingness to pay for resolving the odor problem vary person by person. This is why public sector's intervention is required to get ride of any possibility of market failure resulted from negative external effect of human. This paper has tried to do empirical research based on survey of residents who are currently living in the area of Ochang industrial complex in North Chong-chung province. According to the empirical research results, first of all, it was proven residents' perception of legal regulation has a negative effect on odor acceptance. That is, the more residents are aware of law and regulation, the less they tend to accept odor. In addition, resident's perception on need to improve odor regulation has a positive impact on their odor acceptance. Finally, residents' satisfaction on the legal complaints to local government has an interaction effect to causative relationship between the perception of improving odor regulation and odor acceptance.

• Journal of Environmental Impact Assessment
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• v.25 no.2
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• pp.141-154
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• 2016

This study was conducted laying the focus on finding the mutual action between the substantial ecological value and economic system in the national land, and calculating the environmental carrying capacity and sustainability of the national land using the emergy synthesis. Particularly, this study pays attention watchfully to the reality that the analytic framework to analyze sustainability is not arranged well, as the concept of sustainable development considering environmental carrying capacity, which becomes a widely discussed topic today, is defined differently according to the subjective views of respective researchers, and the situation which needs in-depth evaluation on the interaction between nature and economy which becomes the fundamental of sustainable development. This study also aims at groping for correct direction for the national land development by calculating the environmental carrying capacity and index value which is appropriate to the national land and providing the framework for preparing the policy to induce the sustainable use and management of the national land. The concept of emergy synthesis which is used for the evaluation of environmental carrying capacity and sustainability in the national land, as in this case, can notify the information on current situation of the national land as well as explain how the national land transforms according to time pass (the role of information synthesis), and gives knowledge if the national land policies advances toward the direction of sustainable development (the role of policy evaluation and observation). Emergy synthesis also can take role for selecting best policy on the process of decision making on the exploitation of the national land (the role on the process of decision making).

• Journal of Environmental Impact Assessment
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• v.19 no.5
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• pp.475-481
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• 2010

Lots of pollutants typically originating from urban transportation are accumulating on the paved surfaces during dry periods and are washed-off directly to the river during a storm. Also, paved surfaces are contributing to increase in peak flows and volume of stormwater flows. These are the main reasons why the water quality of rivers and lakes remain polluted and still below standards. Currently, several management practices are being applied in developed countries but the design standards are still lacking. This research was conducted to develop a treatment technology that can be useful to address the problems concerning runoff quality and quantity. A lab scale infiltration device consisting of a pretreatment tank and media zone was designed and tested for various flow regimes characterizing the low, average and high intensity rainfall. Based on the experiments, the high intensity flow resulted to increase in outflow event mean concentration (EMC) of pollutants, about twice as much as the average outflow EMC. However, 78 to 88% of the total suspended solids were captured and retained in the pretreatment tank because of sedimentation. The removal of heavy metals such as zinc and lead was greatly affected by the vertical placement of woodchip layer prior to the media zone. It was observed that the high carbon content (almost 50%) in the woodchip provided opportunity for enhancing its uptake of metal by adsorption. The findings implied that the reduction of pollutants can be greatly achieved by means of proper pretreatment to allow for settling of particles with a combination of using high carbon source media like woodchip and a geotextile mat to reduce the flow before filtering into the media zone and finally discharging to the drainage system.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.4
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• pp.464-476
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• 2019

Objectives: This study aimed to assess the exposure levels of tollbooth workers to diesel particulate matter using black carbon (BC) and to find the correlations among variables associated with BC using the motor vehicle management act regulated by the Ministry of Land, Infrastructure and Transport. Methods: This study was performed over 14 days at a university in Seoul. BC levels were monitored using an aethalometer and were conducted around the breathing zones of the workers. There were three sampling locations: inside the tollbooth (front gate and rear gate) and an office as a control group. T-test, correlation, and multiple linear regression analysis were performed using SPSS. Results: The geometric mean (GM) of BC_30min concentrations in the exposure group was 2.44 ㎍/㎥, approximately 1.4 times higher than the control group (1.75 ㎍/㎥). The GM of BC_30min concentrations was 2.75 ㎍/㎥ during the heavy traffic time (9-10 am) and 2.30 ㎍/㎥ during non-heavy traffic times (p<0.001). The multiple linear regression analysis shows that the number of all types of vehicles and PM_2.5 concentrations in the atmosphere were factors increasing the GM of BC(ln(BC_30min)) concentrations (adjusted R²=0.42, p<0.001). The workers were constantly exposed to low concentrations (GM of BC_30min=2.44 ㎍/㎥), but they were exposed to peak concentrations instantly (BC_10sec=3545.04 ㎍/㎥). When the GM of BC_30min concentrations was momentarily represented as high, it was identified that a vehicle mainly using diesel fuel or an aging vehicle had passed. Conclusions: A ventilation system should be installed in the closed tollbooth or aging vehicles should be controlled so as not to pass tollbooths.

• Journal of Engineering Education Research
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• v.13 no.6
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• pp.152-163
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• 2010

Civil engineering based on construction and maintenance of infrastructures for social and human development, it has a conservative aspects to adopt the high-technology and pace of change from ancient society. Therefore, the education of civil engineering consists of very similar contents from the past until now. Also, civil engineering, area is established the infrastructure widely included structure, geotechnical, hydraulic, environmental, surveying, construction management. Civil engineering have totally difference characteristics compared to manufacturing industry field for market interests such as mechanical engineering, chemical engineering, material engineering etc. Therefore, the capstone design concepts of civil engineering for public interests must be changed and applied unlike any other engineering areas capstone design. In this paper, the modified capstone design contents and instruction in civil engineering of Yonsei University is informed and evaluated using undergraduate students' course evaluations and learning assessment to verify the efficiency of modified capstone design in civil engineering.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.10
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• pp.909-918
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• 2009

As a part of dissolved organic matter, dissolved organic carbon (DOC) or biodegradable DOC (BDOC) fraction in particular is one of important issues in water treatment. Due to role as a nutrient source for bacteria, BDOC, therefore, may cause regrowth problems in water distribution system. The main objectives of this study were to investigate the possibility to minimize the concentration of BDOC in advance water treatment process. DOC in water is fractionized into four fractions such as AnBDOC (adsorbable and non-biodegradable DOC) which possesses adsorption properties but no biodegradation ability; nABDOC (biodegradable and non-adsorbable DOC) which has biodegradation properties but no adsorption ability; ABDOC (adsorbable and biodegradable DOC) which has adsorption properties and biodegradable characteristic; and non-removal DOC (nAnBDOC) which do not have either adsorbability or biodegradability. BAC process was effective for adsorbable DOC (AnBDOC+ABDOC) removal. However, in some cases, the removal ratio of adsorbable DOC was not sufficient. BDOC removal rate is very low or irremovable. Thus, for the control of residual DOC, it is necessary to change the operation condition by BAC process. From the analysis results of DOC fractions, water treatment processes appeared to be effective because it could grasp a remarkable amount of biodegradable, adsorbable and non-removal DOC. The concentration of AOX in non-prechlorination process was reduced from 7.1 ${\mu}g$/L to 0.51 ${\mu}g$/L in BAC process followed by ozonation.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.2
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• pp.132-138
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• 2009

The energy efficiency and environment-friendly aspect of the railway system would be superior to other on-land transportation systems. In a preliminary feasibility study stage and selection of optimal railway corridor, the energy efficiency and problems related to environment are usually not considered. For the selection of optimal railway corridor, geographical features and facility of management are generally considered. Environment effect factors for the selection of environment-friendly railway corridor are focused and studied in this paper. In this study, various analysis of opinion of specialists (railway, environment, transport, urban planning, survey) and the guideline for construction of environment-friendly railway were accomplished. From these results of various analysis, 7 major categories (topography/geology, flora and fauna, Nature Property, air quality, water quality, noise/vibration, visual impact/cultural assets) were extracted. To select environment friendly railway corridors, many alternatives should be compared optimal corridor must be selected by a comprehensive assessment considering these 7 categories. The investment for railway systems can be encouraged by the considering of main environmental effect factor evaluated with the modified environmental weight factors for environment-friendly railway construction.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.5
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• pp.163-173
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• 2020

In this study, on-site corporate instructors participated as student-cum-workers in a degree-linked high skills Meister course to improve job competency and practical ability as proposed in the Work-Study Career Vision. Evaluation questions were then developed and their validity was verified by assessing satisfaction related to expected goals in enhancing advanced training guidance and competency as an evaluator. Satisfaction assessment was conducted based on training preparation, training implementation, training effectiveness and training administration. The Delphi Method was adopted and a total of 48 items were developed in 6 categories under 4 main areas. There were 7 evaluation items on the satisfaction of training course development under training preparation, 21 evaluation items related to the satisfaction of Off-JT and OJT courses under training implementation, 16 evaluation items related to the satisfaction of increased competency as an on-site corporate instructor and the satisfaction of enhanced practical skills and skills application at work under training effectiveness, as well as 6 evaluation items to assess satisfaction with administrative support under training administration. The final conformity assessment was conducted based on the stability, content validity ratio, consensus and convergence indicators of the developed items. Results of this study do not only apply to quality management of the high skills Meister course which is being promoted as a pilot project for work-study programs, but also serves as a rationale that may be considered as a basic research tool in the collection of various opinions to derive overall system improvement factors for the work-study high skills Meister course.