• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.1243-1249
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• 2010

Ground anchors can be good solution in large and deep excavation. Anchored supports generally provide larger workspace than strut supports and good performances. The major benefit provided by these anchored systems was the open excavation area created by eliminating horizontal or raked struts, which generally inhibit rapid construction within the site area. In loose soils, however, anchors are sometimes hard to get high pullout anchor capacity, so that the spacing of anchor both horizontally and vertically is frequently controlled, in which the construction costs of anchors are increased. In order to increase anchor capacity, therefore, conceptual introduction of the multi-strand anchor is presented in this paper. Also, this study shows an numerical study of predicting the load transfer of the multi-strand anchor and a beam-column analysis was performed by a Elastic-Plastic beam theory.

• Computational Structural Engineering : An International Journal
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• v.1 no.1
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• pp.59-69
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• 2001

This study is intended to propose a systematic approach for reliability-based assessment of life cycle cost (LCC) effectiveness and economic efficiency for cost-effective seismic upgrading of existing bridges. The LCC function is expressed as the sum of the upgrading cost and all the discounted life cycle damage costs, which is formulated as a function of the Park-Ang damage index and structural damage probability. The damage costs are expressed in terms of direct damage costs such as repair/replacement costs, human losses and property damage costs, and indirect damage costs such as road user costs and indirect regional economic losses. For dealing with a variety of uncertainties associated with earthquake loads and capacities, a simulation-based reliability approach is used. The SMART-DRAIN-2DX, which is a modified version of the well-known DRAIN-2DX, is extended by incor-porating LCC analysis based on the LCC function developed in the study. Economic efficiencies for optimal seismic upgradings of the continuous PC segmental bridges are assessed using the proposed LCC functions and benefit-cost ratio.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.6
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• pp.869-875
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• 2011

Ministry of Environment has been promoting BTL business of the sewer rehabilitation which continues from 2005 up to now. Sewer rehabilitation is classified into three parts : wastewater pipe rehabilitation, rainwater pipe rehabilitation and drainage equipment rehabilitation. Drainage equipment rehabilitation is that drainage pipe connects wastewater pipe directly without water-purifier. In the drainage equipment construction, it is inevitable to have the damage of ground structures(wall, gate and U drain, etc) when an open excavation method is used. Therefore it is necessary to develop non-excavation method to connect drainage pipe and wastewater pipe like jacking method to avoid the damage of ground structure. This paper has conducted an analysis of the non-excavation method using a boring machine attached to backhoe, which is issued the verification certificate of environmental technology according to the Development of and Support for Environmental Technology Act, article.7. The index set in this analysis was sectionalized to the condition of construction, the grade of drainage pipe, the size of excavated hole, the amount of waste cement concrete and asphalt concrete and the benefit effect compared to open excavation method.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.1
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• pp.57-63
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• 2015

Recently, Korea's municipal wastewater treatment plants generated amount of wastewater sludge per day. However, ocean dumping of sewage sludge has been prohibited since 2012 by the London dumping convention and protocol and thus removal or treatment of wastewater sludge from field sites is an important issue on the ground site. The hydrothermal carbonization is one of attractive thermo-chemical method to upgrade sewage sludge to produce solid fuel with benefit method from the use of no chemical catalytic. Hydrothermal carbonization improved that the upgrading fuel properties and increased materials and energy recovery, which is conducted at temperatures ranging from 200 to $350^{\circ}C$ with a reaction time of 30 min. Hydrothermal carbonization increased the heating value though the increase of the carbon and fixed carbon content of solid fuel due to dehydration and decarboxylation reaction. Therefore, after the hydrothermal carbonization, the H/C and O/C ratios decreased because of the chemical conversion. Energy retention efficiency suggest that the optimum temperature of hydrothermal carbonization to produce more energy-rich solid fuel is approximately $200^{\circ}C$.

• Horticultural Science & Technology
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• v.35 no.2
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• pp.252-264
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• 2017

Tea is one of the most consumed beverages worldwide and the relatively high levels polyphenols is benefit for health. In this study, we developed an efficient system for proliferation of callus from 'Anji Baicha', a cultivar of tea (Camellia sinensis). Callus tissue was initially induced by culturing leaf explants on medium containing different plant growth regulators. For callus induction, thidiazuron (TDZ) was more effective than 2,4-dichlorophenoxyacetic acid (2,4-D), ${\alpha}-naphthalene$ acetic acid (NAA), and $N^6-benzyladenine$ (BA). The frequency of callus induction from leaf explants reached 90.21% on $1.0mg{\cdot}L^{-1}$ TDZ and the developed callus was reddish and friable. We also tested the effect of different concentrations of NAA, 2,4-D, indole 3-acetic acid (IAA), BA, and TDZ, alone and in combinations, on callus proliferation. Medium supplemented with TDZ in combination with IAA was suitable for callus proliferation and accumulation of tea polyphenols. The growth index value and tea polyphenol content of callus cultured on MS medium containing $0.5mg{\cdot}L^{-1}$ TDZ and $1.0mg{\cdot}L^{-1}$ IAA was maximally 1,351% and 23.24%, respectively, and the relative abundance of epicatechin was as high as 17.449%. We also measured the antioxidant activity of all samples and the callus with the highest tea polyphenol content also exhibited high potential radical scavenging activity.

• Journal of the Korean Geographical Society
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• v.40 no.6 s.111
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• pp.671-693
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• 2005

This paper is to explore critically environmentalism, especially in terms of environmental justice, suggested or implied in theory of liberalism which has been the ideological foundation of contemporary society. It begins with a brief look at liberal perspective in a broad sense, then interprets in-depth the classical liberalism of J. Locke, libertarianism (esp. R. Nozick) and utilitarianism (including cost-benefit analysis) from the environmental point of view. And finally it considers liberal pluralism and other alternative theories of pluralism, especially communitarianism (esp M. Walzer), postmodern pluralism (esp. I. Young), and cultural pluralism (esp. C. Taylor) in order to overcome limitations of liberal environmentalism and to find out some clues for theory of environmental justice. In conclusion, this paper argues that we need to transfer from liberalism (including liberal pluralism) to critical pluralism in oder to develop a proper understanding of environmental problems and to conceptualize a desirable theory of environmental justice.

• Journal of the Korea Society of Computer and Information
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• v.27 no.12
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• pp.293-301
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• 2022

Based on the VAM model of the consumer behavior research framework, combined with the altruistic variable of environmental awareness, this paper constructs a research model on the impact of perceived value, perceived risk and environmental awareness on purchase intention, and deeply analyzes the driving factors of perceived value and perceived risk. By collecting 612 valid questionnaires, data was analyzed by using SPSS 24.0 and AMOS 24.0, the results were concluded. Perceived usefulness, perceived entertainment, Technicality, and Energy Awareness all have a significant positive impact on the purchase intention of new energy vehicles; Perceived Fee has a negative impact on purchase intention. The results of this study can provide strategies for companies to improve marketing, reduce consumers' perceived risks, provide beneficial supplements to companies in promoting the environmental protection attributes of new energy vehicles and their own environmental protection efforts, and promote the balance of economic and environmental benefits.

• Archives of design research
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• v.16 no.3
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• pp.329-340
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• 2003

The purpose of this study is to provide the methods of harmony in color combination of environmental color for apartment in order to improve the image of the urban landscape. For this study, apartment in Iksan City was selected is a sample and twenty two apartments were analyzed. This framework of this study is A. Hard and L. Sivik's color combination model based on Natural Color System. This study examines various theories on environmental color perception and new approaches to color aesthetics, and tries to present perceptual properties that can be applied to environmental color design First, the principle of color harmony feeling in based on nuance and tone. Therefore, to control brightness and chromaticness with are related with nuance is important in color combination. Second, the aesthetic experience in color preception can be defined as a combined effect of similarities and differences of color attributes. Third, color harmony theory is one of the areas that can be benefit a great deal from and interdisciplinary approach, add empirical study such as this can be used as a basis for environmental color design and evaluation.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.5
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• pp.455-460
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• 2010

This study was carried out to find out any inherent problems occurring in the sampling and analytical procedures, and to suggest the relevant solutions to the problems. In addition, an optimal condition of clean-up process was developed, which was based on a method using silica glass column. As a result of experiments to test any artificial contamination of blank samples such as glassware and collection media, artifacts of DBP and DEHP appeared to be detected in various kinds of laboratory tools and apparatuses used in the sampling and analytical works. Therefore, it is necessary to investigate a degree of contamination before laboratory works by conducting a prior check any possible contaminations in all experimental tools and apparatus. It is also necessary to devise a method to avoid a tool, if possible, or to use a substitute of phthalate free. If the use of any plastic tool to cause contamination is inevitable, it should be properly corrected with a blank level, as is equally treated as the sample. The clean-up process demonstrated in this study can give us a significant benefit in terms of the quantity and quality of a target compound by GC/MS analysis.

• Journal of Environmental Impact Assessment
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• v.8 no.4
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• pp.59-72
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• 1999

The purpose of the study is to propose the concrete and realistic alternative measures for $CO_2$ emission reduction on commercial sector. To achieve the purpose, this study adopted AIM/KOREA simulation model modified from AIM(Asia-Pacific Integrated Model) originally developed by Japan National Environmental Research Institute. The results of simulation demonstrate that the $CO_2$ emission from the commercial sector in 1995 was estimated 864 million TC(tons of carbon); however, according to the base scenario, $CO_2$ emission in 2020 is expected to be increased to 1,872 million TC, which is 2.17 times greater than that in 1995. In order to mitigate the ever-increasing $CO_2$ emission, the results of AIM/KOREA simulations under various scenarios showed that the 30-thousand-won carbon tax scenario does not successfully motivate the selection of advanced technology; however, with the 300-thousand-won carbon tax, a substantial amount of $CO_2$ emission reduction by 1.69 million TC from the BaU((Business-as-Usual)scenario is expected to be achieved by year 2020. Such substantial reduction of $CO_2$ emission under the 300-thoudsand-won carbon tax scenario is due to the introduction of advanced technology, such as use of condensing boilers, forced by heavier carbon tax. Under the scenario that presumes the maximum introduction of gas-burning industrial appliances, an 2.66 million TC of $CO_2$ reduction was expected. The results of this study suggest that the $CO_2$ emission reduction measures can be interpreted in many different views. However, if people and industries are fully aware of the economic benefit of energy saving, a certain level of $CO_2$ reduction by a successful introduction of advanced energy saving technology appears to be achieved without carbon tax or subsidies.