• 농업생명과학연구
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• 제50권1호
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• pp.137-146
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• 2016

This experiment was designed to assess the physical and chemical properties of growing media substituted with a range of increasing concentrations of pretreated wood and to relate these properties to plant growth responses. For preparing the growing media, each material was combined with rural soil, peat, perlite and pretreated wood. Physicochemical properties studied were similar to ideal substrate ranges for plant growth on growing media, including pretreated wood. Physical properties were also well maintained over time. In comparison to plants growing in 100% rural soil, tall fescue(Festuca arundinacea) in the prepared growing media achieved better growth, especially when using the 50% rural soil + 50% PPW(peat + perlite + pretreated wood, 3:1:6(w/w/w)) and 30% rural soil + 70% PPW (peat + perlite + pretreated wood, 3:1:6(w/w/w)), and showed improved germination percentage. We confirmed the potential use of growing media, including pretreated wood. Furthermore, our results show a correlation among the physicochemical properties of tall fescue(Festuca arundinacea); physical properties were significantly influenced by germination and aerial parts. The root length of physicochemical properties was correlated with bulk density and organic compound (p<0.01).

• 한국환경보건학회지
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• 제34권1호
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• pp.101-107
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• 2008

Bio-filtration utilizes microorganisms fixed to a porous medium to metabolize pollutants present in an air stream. The microorganisms grow in a bio-film on the surface of a medium or are suspended in the water phase surrounding the medium particles. Therefore, bio-filter support media play one of the most important key roles in bio-filtration of gas phase pollutants. To characterize and select the appropriate support media, gas adsorption capacity and microorganism immobilization were investigated in lab-scale experiments for the selected target support media which were compost I (compost from lab-scale process), compost II (compost from municipal facility), bark, wood chip, orchid stone and vermiculite. As odor materials, ammonia and trimethylamine were utilized. From the result of experiments, bark was superior to any other support media tested in adsorption capacity as much as 12.5 mg ammonia per 1 g bark. In trimethylamine adsorption, bark and wood chip showed a remarkable results of 21.1 and 14.1 mg/g respectively. On the other hand, microorganism fixation test determined by the count of nitrogen oxidizing microbes population, the compost II and wood chips showed the best results. Considering the characteristics of materials and the operating condition of the bio-filter, bark, wood chip, and compost II are applicable to the support media of bio-filter when they are appropriately blended on the basis of studying the media pH, packing porosity and moisture contents.

• 한국환경과학회지
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• 제23권4호
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• pp.681-695
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• 2014

In a pilot-scale dyeing wastewater treatment using two-type fluidizing media, each thickness of biofilm was 15 and 30 ${\mu}m$, respectively. The numbers of protozoa inhabited in small-size (PEMT A) and big-size (PEMT B) media were $7.5{\times}10^4$ and $1.25{\times}10^5$ cells/ml, respectively, and dominant species were Entosiphon sulcatus var sulcatus in PEMT A and Chlamydomonas reinhardtii in PEMT B, respectively. Flask experiments using the two media revealed that the percentages of color removal were 25.8% in PEMT A and 27.1% in PEMT B after 72-h cultivation, indicating the necessity of bioaugmentation. Experiments for bioaugmentation effect on color removal were carried out in the pilot-scale treatment for 75 d by three-step operation under the control of wastewater loading rate and microbial input rate. Dye degradation occurred mainly in the second reaction tank, and the attachment of augmented dye-degrading microorganisms to media took at least 35 d. Final value of chromaticity in effluent was 227, meeting the required standard. Therefore bioaugmentation onto media was good for color treatment. In summary, thickness of biofilm formed on the media depended upon the size of media, resulting in different ecosystem inside the media. Hence, this affected microbial community and color treatment further. Accordingly, the reduction of operation cost is expected by efficient color-treatment process using bioaugmented media.

• 한국물환경학회지
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• 제25권2호
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• pp.306-310
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• 2009

Packed-bed reactor for removing ammonia was tested at different loading rates. Nitrifiers for ammonia removing was encapsulated in gel media which consisted of polyethlene glycol, alginate and activated carbon. The removal efficiency was nearly 100% when ammonia loading was $12g/m^3/hr$, and the maximum elimination capacity (EC) achieved on this study was $18g/m^3/hr$. The initial microbial portion of nitrifiers in the media was about 82% and it was increased to more than 90% at the end of the operation. Short-term shock loading test was carried out to survey the stability of the media. The inlet loading rates were varied from 2 to $20g/m^3/hr$. The packed-bed reactor overcame the shock loading i.e. removal efficiency recovered rapidly from about 80% to almost 100% within 6 hrs. The results of Live/Dead cell test showed that nitrifiers maintained there activity in the encapsulated media during the test and also against ammonia shock load.

• Environmental Engineering Research
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• 제14권4호
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• pp.238-242
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• 2009

This study investigated the effects of organic loading rates on simultaneous carbon and nitrogen removal in an innovative fixed-film aerobic bioreactor. The fixed-film bioreactor (FFB) was composed of a two-compartment aeration tank, in which a synthetic filamentous carrier was submerged as biofilm support media, and a settling tank which polyvinylidene media (Saran) was used as settling aid for suspended solids. Three different organic loading rates, ranging from 0.92-2.02 kg chemical oxygen demand/$m^3$/day were applied by varying hydraulic retention time (HRT). The total soluble organic carbon removal efficiencies were in the range of 90-97%. The removal efficiency of ammonia was found to be in the range of 70-84%. Total nitrogen removal efficiency was found to be in the range of 40-45%, which indicates that denitrification reactions occurred simultaneously in the attached biofilm on the fibrous media in the aeration tank. The settling performance of suspended solids was significantly improved due to the presence of Saran media in the settling compartment, even for a short HRT. The fixed-film aerobic bioreactor used in this study demonstrated efficient treatment efficiency even at higher organic loading rates and at short HRTs.

• The Journal of Asian Finance, Economics and Business
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• 제8권1호
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• pp.187-198
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• 2021

The objective of this study is to examine the direct and indirect influences of government's role, organizational commitment, and media exposure on the corporate social and environmental responsibility disclosure (CSERD) of 42 Indonesian state-owned enterprises (SOEs) with good corporate governance as the mediator. This study uses a quantitative approach with path analysis to test the hypothesis. The sample in this study was directors of 42 state-owned enterprises in Indonesia. The data was collected using a questionnaire with items assessed on a five-point Likert scale. This study finds that 1) the government's role, organizational commitment, and media exposure have direct influences on good corporate governance and corporate social responsibility disclosure; 2) the government's role and organizational commitment have significant influences on corporate social and environmental responsibility disclosure with the mediation of good corporate governance, indicating that government's role and the organizational commitment are factors affecting Indonesian state-owned enterprises; and 3) the media exposure through good corporate governance mediation does not have a significant effect on corporate social and environmental responsibility disclosure. This means that media exposure is only one of the tools for CSERD, while SOEs have no obligation to disclose CSER through website or printed media.

• 교육녹색환경연구
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• 제10권3호
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• pp.17-26
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• 2011

National efforts responding to climate change is directly connected to competitiveness of the urban environment. Practice in the daily life of the individual citizens is prerequisite for the paradigm shift that can be made by the reduction of the city's energy consumption and low-carbon green growth. Therefore, the comprehensive understanding combined with the educational programs is required on the issue of the ecological environment and the urban environment competitiveness. In this paper, the meaning and role of urban ecological environment will be researched first. it also takes a look at the content of curriculum and analyses domestic policies related to environmental education of primary and middle schools. In addition, video documentary on urban ecological environment will be analyzed for the development of educational media dealing with environmental training in schools. Consequently, urban ecological environment shown in video media content will be identified and the advantage of this possibility as a medium of education is to be proposed.

• 한국환경과학회지
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• 제17권10호
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• pp.1183-1193
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• 2008

Today, environmental pollution and destruction due to the industrialization of our modem society have been the global issues. Although now we can lead affluent lives through science technologies and economic development, these environmental problems have resulted in striking the harmonious balance between human beings and nature and threatened human lives with abnormal weather caused by the global warming, destruction of the ozone layer, and El Nino phenomenon, acid rain, decrease in species diversity, movement of hazardous materials, and harmful waste increase. We are aware of the importance of environmental education, but in reality, it seems impossible to implement appropriate environmental education on account of our educational climate which exclusively focuses on the entrance examination. However, environmental education is the most ultimate solution for those problems in that only when students understand our environment fully and grow habits to protect it through environmental education, the present environmental problems can be solved and more serious problems that can be resulted in the future can possibly be prevented. Thus, this study has examined the effect of using image media in the environment subject on students' environmental sensitivity. According to the results, it was shown that it had positive effects on 'sensitivity of environment', 'attitudes towards environment', and 'environmental affinitive behaviors'.

• 대한가정학회지
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• 제37권9호
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• pp.103-127
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• 1999

The effects of environmental factors on adolescent’s socialization were examined according to the gender. Data were drawn from 1,412 adolescents. A hypothesized model was tested for male and female students separately by the links among housing, family conflicts, parent-adolescent relationship, family stress, peer relations, mass media, school atmosphere, consumption, consumer socialization, and adolescent’s socialization. There was no difference between male and female students in the predictability of the effects of environmental factors on internal and external socialization. For male students, the internal socialization was directly related to mass media, consumer socialization, peer relations, family stress, mother-adolescent relations, and school atmosphere. The external socialization was directly related to mass media, school atmosphere, consumer socialization, father-adolescent relations, housing, and mother-adolescent relations. For female students, the internal socialization was directly related to mass media, peer relations, father-adolescent relations, and consumer socialization. The external socialization was directly related to mass media, followed by consumer socialization, mother-adolescent relations, school atmosphere, housing, and peer relations. The findings are consistent with a growing body of literature showing that the environmental factors are related to male & female adolescent’s socialization.

• 한국환경보건학회지
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• 제26권3호
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• pp.76-80
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• 2000

The purpose of this study is to compare the performance of rubble support media coated perlite and non-coated media. As rubble was coated perlite, the porocity of reactor was increased 5.6%, whereas packing weight was decreased 17.6%. When rubble was coated perlite, microorganisms were attached on the surface of support media after 2 hours. TCOD removal efficiency of the reactor packed with rubble support media coated perlite was higher 4~9% than that of rubble. The end of experiment, MLVSS of rubble support media and rubble coated perlite was 1858.8mg/ι, 2785.9mg/ι, respectively.