• 한국물환경학회지
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• 제31권2호
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• pp.87-93
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• 2015

In this study, the inhibitory effect of toxic metals was investigated on the activated sludge of the municipal sewage treatment plant. The allowable concentration of toxic metals was also estimated for the stable operation of the biological treatment process. The single and mixture toxicity of $Cu^{2+}$, $Al^{3+}$ and $Zn^{2+}$ were evaluated for the activated sludge microorganisms. As a result, nitrifying microorganisms were more susceptible than heterotrophic microorganisms. $IC_{10}$ (Inhibition Concentration of 10%) of $Cu^{2+}$, $Al^{3+}$ and $Zn^{2+}$ for the nitrifying microorganisms was 3 mg/L, 7 mg/L and 25 mg/L, respectively. The mixture toxicity showed three times more sensitive than the single toxicity. The concentrations of $Cu^{2+}$, $Al^{3+}$ and $Zn^{2+}$ to minimize the inhibitory effect on organic matter removal and nitrification in batch experiments were found to be 1.3 mg/L, 2.5 mg/L and 6.3 mg/L.

• 대한지역사회영양학회지
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• 제16권1호
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• pp.75-85
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• 2011

The purpose of this study was to investigate basic data on the degree of parents' recognition and satisfaction with the use of environment-friendly agricultural products. The conclusions of this study are as follows. The survey on the use of environment-friendly products in households showed that 68.7% of the respondents used environment-friendly products at home. The frequency of purchasing organic products by household consumers showed that 25.1% of the respondents bought organic products one to two times per week. The most popular items of the environment-friendly agricultural products used were vegetables, comprising 63.9%. The households with more than 3,000,000 won of monthly income tended to consume more domestic livestock products (p < 0.05). In comparison to general agricultural products, environment-friendly agricultural products users showed higher satisfaction level with a better quality in term of safety, quality, nutrition, taste, appearance, diversity and price. The degree of satisfaction with safety was the highest ($3.8{\pm}0.68$), and price showed the lowest ($2.76{\pm}0.79$). The degree of parents' recognition of the governmental support for environment-friendly agricultural products showed that those who were aware of the supporting policy were 44.5%, but 55.5% of them didn't know about the fact that 46.6% of the respondents agreed that environment-friendly agricultural products should be used in more than 50% of the foods used for school food service. The respondents pointed out that vegetables (45%) sprayed with pesticide are the most urgent food item that need to be replaced by environment-friendly farm products.

• 한국실내디자인학회논문집
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• 제17권3호
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• pp.23-33
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• 2008

After the concept of apartments was introduced in 1960s in Korea, on account of the development of architectural technology and science, high-rise residences in Korea are getting higher, and these residences have been becoming high-rise commercial/residential buildings since 1990. Nowadays, as the construction of high-rise commercial residential building complex is booming, the difference between these complex and high-rise apartments is getting smaller, and these two kind of high-rise residences are becoming new residential style in Korea. And these high-rise residences are considered the symbol of wealth owing to the marketing strategy emphasizing high quality, refined interior, a fair view, and the protection of privacy. However, high-rise residences bring about many problems related to health and psychology caused by the consumption of a large amount of energy, pollutant emission, the deterioration of the quality of indoor air, and vibration. For this reason, in this study, we tried to emphasize the necessity of environment-friendly access to provide healthy living environment and to reduce the negative effect of housing life in high-rise residences, and find the method to improve environment-friendly quality and health of residents in interior space. Therefore, this study aims to detect the problems and the items to be improved of interior spaces of high-rise residences by quantitative, qualitative analysis of the evaluation elements and the floor planning elements deduced from environment-friendly architectural certification in Korea and the other countries, and suggest the guideline to improve the environment-friendly quality of these interior spaces.

• 한국산업보건학회지
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• 제31권3호
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• pp.274-285
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• 2021

Objectives: The question of whether the level of fees paid to working environment measurement agencies is appropriate has long been a matter of concern to the government. In addition, measurement institutions express dissatisfaction with their level of compensation, which has a great influence on the evaluation of a subject's policy. This study is intended to find a way to appropriately calculate working environment measurement fees. Methods: We looked at the principle of fee determination as a basic theory of fee calculation used in fee calculation, the legal and academic aspects of the general method of fee calculation, and government cost calculation standards. Furthermore, we reviewed the research methods applied so far to derive a method of calculating fees appropriate for this environment. Results: The working environment measurement environment is different from other commission calculation environments. The other environment is to appropriately calculate the service price provided by a monopoly public enterprise, while the situation is to appropriately calculate the fees provided by competitive private enterprises. Therefore, the service delivery environment and the delivery entity are different. In this case, the appropriate method of calculating service fees would be competitive pricing. There have also been many problems under the method of calculation by service cost. Conclusions: First, the working environment measurement fee requires an accounting correction of endogenous variables. Second, the theory of calculating fees appropriate for this situation is appropriate for competitive pricing that applies to private competitors. Third, the government should make efforts to make the service supply market a fully competitive market while ensuring that the service fee level is determined at the marginal cost level. Fourth, economically, research on marginal cost levels is needed.

• 한국기계가공학회지
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• 제17권6호
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• pp.136-143
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• 2018

Recently, with the rapid development of virtual reality technology, there have been more and more applications of virtual reality technology in various fields. In order to realize a virtual reality, a method of implementing a visualization environment through an HMD (Head Mounted Display) is widely used. However, in the current visualization environment through the HMD, the user feels dizziness when worn, It has the disadvantage of imposing restrictions on. In this study, it is aimed to realize virtual reality visualization environment through multi-screen environment which improves the experience effect of virtual environment by using existing screen instead of visualization through HMD, and compensates for shortcomings of HMD method. In order to realize a multi-screen environment as a highly visualized environment, a technique for matching the spatial position of the multi-screen with the spatial position of the virtual environment is required. To do this, we need an efficient method to precisely measure the position of the space, and we propose a spatial position compensation methodology that can efficiently and precisely measure the position of the real space and reflect it in the virtual environment.

• 한국물환경학회지
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• 제38권2호
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• pp.72-81
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• 2022

Numerous studies have investigated the occurrence and fate of microplastics in the environment; however, only limited effort has been devoted to exploring the characteristics of dissolved organic matter (DOM) leached from microplastics. In microplastic (MP)-contaminated environment, MPs are typically mixed with naturally-occurring particles, which interferes with their detection in the environment. Thus, it is necessary to distinguish between the DOM leached from MPs and those leached from natural particles and also to characterize their properties. This study investigated DOM leaching behavior from MPs (polystyrene: PS, polyvinylchloride: PVC) and natural particulates (forest soil: FS, litter leaves: LL) under light, which is considered one of the main weathering processes that affect MPs in the environment. The leached DOM concentrations and fluorescence characteristics were compared under dark versus light conditions. Regardless of the origins, UV light promoted DOM release from all the particulates. More DOM was released from natural particles than from MPs under both conditions. However, the effect of promoting DOM release by UV was more pronounced for MPs than for natural particles. It was observed from fluorescence spectra that the intensity of the humic-like region was substantially reduced when MP-derived DOM was exposed to UV light, whereas the change of intensity was very little for natural particles. Under light conditions, the ratio of protein-like to humic-like fluorescence of MP-derived DOM was higher than that of DOM from natural particles. This study implies that a substantial amount of DOM could be leached from MPs even in MP-polluted environment under UV irradiation. Protein/humic fluorescence ratio could be utilized as a fast probing indicator to separate the two sources of particles under light.

• 한국물환경학회지
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• 제38권6호
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• pp.316-326
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• 2022

This study aimed to investigate the causes of the increasing Total Phosphate(TP) in the mainstream of Mangyeong river over the past 10 years, and suggested a reduction plan of about 3 points. First, the high TP concentration was continuously released in the discharge outlet of the Haepo bridge stormwater pipeline. The average TP concentration was 5.066 mg/L and values as high as 29.470 mg/L were measured. The highest pollution contribution rate to the Mangyeong river was more than 70 %. The cause of the pollution was expected to take place somewhere in Wanju Industrial Complex. Second, the average TP concentration of wastewater-treated effluent in the H factory was 0.405 mg/L. If a TP reduction facility is additionally installed in the H factory, it will help reduce TP uptake by Lake Saemangeum. Third, the TP concentration of untreated non-point source point flowing into the Samrae stream was very high with an average of 2.828 mg/L. Also, the pollution contribution rate of Samraecheon 2 to Mangyeong river was 21.8 % on average and up to 58 %. The pollution contribution rate was also high during the agricultural season and the winter, during which the flow rate is decreased. Investigation of these three points may be continuously needed, and analysis results and policy proposals presented to Jeollabukdo and Wanjugun to manage pollution sources.

• Fisheries and Aquatic Sciences
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• 제4권2호
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• pp.65-69
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• 2001

For the first time the concentrations of copper, zinc, lead, cadmium and crome in the tissues from 17 specimens of cetaceans of Korean coast were determined. The measured concentrations of trace elements were considerably lower than the concentrations previously reported in cetaceans. In inter-species, Cd levels were higher in the kidney of Stejneger's beaked whales and the stomach, liver and lung of Risso's dolphin than in the tissues of minke whale and humpback whale.

• 한국주거학회논문집
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• 제16권1호
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• pp.11-16
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• 2005

The purpose of this study is to find out the present thermal environment of the Korean livingroom in comparison with the Japan's. Thermal environment of the livingroom with radiant floor heating system in Korea and Japan is analysed. The surveys and measurements are took place in two detached houses and two apartments in Seoul, Korea and two apartments in Tokyo, Japan for a 48-hour period at the beginning of March, 2003. The result of this study shows that the thermal environment of the livingroom in Korean houses, especially in the apartments is warmer and stabler than the Japan's. However, despite of its high temperature, Koreans have a tendency to rise their room temperature creating excess.

• 수산해양기술연구
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• 제53권1호
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• pp.67-76
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• 2017

This study carried out and analyzed survey data on captains and mates of Korean coastal large trawlers in order to examine factors affecting body abnormalities and fatigue on bridge teams from work and environment at bridges of trawlers. The summarized result may be summed up as follows: multiple regression analysis with body pain and fatigue as dependent variables yields t-values of -2.559 (p<0.05) and -3.928 (p<0.05) respectively. From the result, environment at bridges (views, spaces and exhaust) were negative factors in affecting bridge workers' pain and fatigue. Thus, it is determined to secure available spaces to improve the workers' views through windows in front of, besides and rear bridge and create more pleasant atmospheric environment at bridge.