• Journal of Environmental Impact Assessment
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• v.23 no.5
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• pp.406-416
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• 2014

When abnormal taste and odor were detected in the tap water of the North-Han river watershed during the dry season in late 2011, excessive nutrients with algal growth in the Lake Uiam and weather factors were considered to be among its causes. The nutrients, in particular, originated from domestic sewage in the Chuncheon area. This study was conducted to investigate relations between the algal growth in the Lake Uiam and the contribution of nutrients from public sewage treatment works (PSTWs) in Chuncheon city, and based on this to analyze the environmental impact. Nutrients in the Lake Uiam have already been accumulated to the level of eutrophication. Even in winter, the conditions in the lake such as retention time and water temperature were favorable to boost algal growth. After phosphorus treatment processes were introduced, the PSTWs in the Lake Uiam watershed were able to reduce the total phosphorus loads by 43%. The algal concentrations in the Lake Uiam also dropped by about 7%. The nitrogen treatment efficiencies in the PSTWs, on the other hand, remained almost the same after the introduction of the phosphorus treatment processes. To solve these problems more efficiently, it is necessary to develop management strategies for the upstream area of the Lake Uiam and set plans to improve nitrogen treatment operation and management for the PSTWs in Chuncheon.

• Korean Journal of Occupational Health Nursing
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• v.13 no.2
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• pp.104-117
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• 2004

Objectives: To propose the basic data for the development of the optimum health promotion program (HPP) for the workers in a petrochemical industry complex. Methods: The subjects were 553 workers who worked at the six plants in a petrochemical industry complex. From February to March 2003, questionnaire survey was conducted by the nurses with occupational health specialty about the life styles, interests, self-cognitions, practices of health behavior, subjective symptoms thought to be related the working environments, burden to the own health, needs and intentions to participation of the HPP. Data analysis was done using SPSS program (ver 10.0) with ${\alpha}=0.05$ of statistical significance. Results: The mean age and tenure of the subjects were 39.7 years and 14.2 years, respectively, and proportion of smokers was around 50%. Two of third (66%) satisfied their own job, and 58% recognized themselves healthy. The most frequent health behavior were exercise (60%) and regular health check (87%) in individual and job based, respectively. About half of them (58%) had at least one of the symptoms thought to be related the working environments, and the most frequent one was odor (21%). These symptoms were more frequent in case of the shorter career. The needs of HPP was relatively higher in exercise (66%), cancer prevention (51%), stress control (47%), and intention to participation was also the highest in exercise (64%). Job satisfaction was higher in case of the higher interests and cognitions to their own health, and thought that the ownership's interest to workers' health be high (p<0.01), but no associations with the subjective symptoms. The mean level of burden to the own health were $14.1{\pm}13.9$ of physical, $11.7{\pm}13.6$ of emotional, $9.1{\pm}10.7$ of behavioral as out of one hundred. They felt the more burden in case of office workers, the lower interests and cognitions to their own health, the lower satisfaction to their job, the frequent drinking group, and complained the subjective symptoms (p<0.05). Abnormal results of the regular health check was higher in the frequent drinking group (p=0.083). Conclusions: For the optimum HPP for the workers in the petrochemical complex, the ownership's interest to workers' health would be enhanced, and the priority would be focused on exercise and drinking habits control.

• Journal of Korea Water Resources Association
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• v.56 no.6
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• pp.373-380
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• 2023

Due to abnormal climate phenomena and climate change in Korea, overgrowth of algae in rivers and reservoirs occurs frequently. Algae in rivers are classified into green algae, blue-green algae, diatom, and other types, and some species of blue-green algae cause problems due to odor and the discharge of toxic substances. In Korea, an algae alert system is in place, and it is issued based on the number of harmful blue-green algae cells. Thus, measuring harmful blue-green algal blooms is very important, and currently, the analysis method of algae involves taking field samples and determining the cell count of green algae, blue-green algae, and diatoms through algal microscopy, which takes a lot of time. Recently, the analysis of algae concentration through Phycocyanin, an alternative indicator for the number of harmful algae cells, has been conducted through remote sensing. However, research on the analysis of the number of blue-green algae cells is currently insufficient. In this study, we water samples for algal analyses were collected from river and counted the number of blue-green algae cells using algae microscopy. We also obtained the Phycocyanin concentration using an optical sensor and acquired algae spectra through a hyperspectral sensor. Based on this, we calculated the equation for estimating blue-green algae cell counts and estimated the number of blue-green algae cells.