• Journal of Environmental Policy
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• v.11 no.3
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• pp.149-170
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• 2012

The United Nations Climate Change Conference, Durban 2011, ended on December 12, 2011, 36 hours over its schedule, delivering the Durban Package, which consisted of, inter alia, the extension of the period for Kyoto Protocol term and the launch of Ad-hoc working Group on the Durban Platform for Enhanced Action. Despite the positive progress made in Durban, the future of post-2012 climate regime still seems cloudy. Before the Durban conference, some of Annex I countries with emissions reduction commitment under the Kyoto Protocol's first commitment period openly declared their intention not to participate in the second one, reducing the effectiveness of Durban agreement. Parties to the conference have a long list of difficult issues disturbing the materialization of the new legal agreement in 2020 such as level of mitigation targets of individual countries and legal nature of their commitment. Given this uncertainty, the Korean government should reinforce its domestic climate policies rather than settling in the fact that it remains as a non-Annex I county party under the Durban Agreement due to the extension of the Kyoto Protocol period. Domestically, it needs to continue to raise the public awareness for rigorous climate policies to transit its economy to low carbon pathway which reduces the country's dependency on fossil fuel in the long term. It is also important to implement cost effective climate policies to cope with domestic resistance and international competitiveness. Internationally, its priority would be working for trust-building in the on-going negotiation meetings to encourage meaningful participation of all parties.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.390-397
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• 2019

A mechanical model of band sawing saw frame was established according to an analysis of a commonly used saw-frame structure diagram to overcome the problems of low service life, substandard cutting precision and efficiency, and high manufacturing cost caused by the unreasonable design of saw frame. Taking a particular type of sawing machine as an example, stress cycle analysis of the saw blade was carried out according to the mechanical model of the saw frame, and the fatigue analysis model of the most dangerous cross-section point that was most prone to fatigue failure of the saw blade was then established. The fatigue analysis result was used as the basis for the improved design of the saw frame, and the improved detailed saw-frame design parameters were obtained. The results suggested that the saw frame system is much more compact and the saw blade force met the fatigue strength requirements through the improved design. In addition, the service life of the saw blade and the cutting precision were increased. The established mechanical model of the saw frame in this paper is used widely and has high practical application values.

• Journal of Conservation Science
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• v.25 no.2
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• pp.219-231
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• 2009

The purpose of this study is to provide basic information necessary for the cleaning of excavated costumes. For the purpose, these researchers reviewed previous records of the actual cleaning of excavated costumes and then implemented and documented the processes of cleaning the Yeosan Song's costumes excavated at Mokdal-dong, Daejeon, which could date back to the early and mid periods of Choseon Dynasty. The excavated clothes of the family provide good examples for comparing men's costume of the 15th century with men's and women's of the mid and late 16th century. The total quantity of excavated remains were 184 and textiles were cotton, silk, hemp, ramie, and union cloth. The clothing remains were processed through wet or dry cleaning in accordance with their fabric condition and the extent to which they were worn or polluted. In detail, the excavated costumes of the Yeosan Song family were cleaned in two stages. For wet cleaning, both anionic(LAS) and nonionic(Triton X-100) surfactants were respectively used as cleaning agents and for dry cleaning, a mixture of n-hexane and n-decane(the ratio of 4 to 6) and petrolic dry cleaning solvent were used. After first cleaning, some cotton, ramie and hemp which had still the stains were processed bleaching and silk which were good condition was processed dry cleaning with the organic solvent again.

• Journal of Energy Engineering
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• v.25 no.3
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• pp.18-26
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• 2016

Mineral oil is the most widely used for electrical transformer, though some factors should be considered such as their environmentally harmfulness when it spill and low flash point. To cover these disadvantages, vegetable oil has developed because of its high biodegradability and thermal stability. However, it is necessary that many studies should conduct to reveal the detailed impacts of long-term operation as transformer oil. In this paper, we applied the accelerated aging test which simulate the real transformer circumstances using insulation paper, coil, steel at $150^{\circ}C$, which is higher than normal operation, for 2 weeks. To figure out the oxidation characteristics between mineral oil and vegetable oil test major properties and components such as total acid number, dielectric breakdown and dissolved gas components during that period. As a result of these tests, we found that vegetable oil has higher electric insulation ability than mineral oil though poor total acid number by hydrophile property. Vegetable oil also kept its thermal stability under the given circumstances.

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.135-144
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• 2007

The dried barks of Maackia amurensis were ground, extracted with 95% EtOH, concentrated, and fractionated with a series of light petroleum ether, dichloromethane, ethyl acetate and water on a separatory funnel. Each fraction was concentrated, then a portion of dichloromethane and ethyl acetate soluble was chromatographed on a Sephadex LH-20 and silica gel 60 column using a various solvent system as eluents. The isolated compounds were identified by cellulose TLC, $^1H-$, $^{13}C-NMR$, COSY, NOESY, HMQC, HMBC, FAB and EI-MS. The structures were determined as: 7-O-$\beta$-D-glucopyranosyl-4'-methoxyisoflavone, 7-O-$\beta$-glucopyranosyl(1'''->6'')-$\beta$-D-glucopyranosyl-4'-methoxyisoflavone, 7-O-$\beta$-D-glucopyranosyl(1''''->6''')-$\beta$-D-glucopyranosyl(1'''->6'')-$\beta$-D-glucopyransoyl-4'-methoxyisoflavone, 7-O-$\beta$-D-glucopyranosyl-4', 6-dimethoxyisoflavone. The Free radical scavenging activity using DPPH of the isolated compounds were similar with that of BHT but lower than of $\alpha$-tocopherol.

• Korean Journal of Microbiology
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• v.40 no.4
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• pp.313-319
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• 2004

The distribution and characteristics of acidotolerant heterotrophic and naphthalene-degrading bacteria were investigated in two forest areas, one near Ulsan petrochemical industrial complex (Sunam) and the other in countryside (Daeam). Average values of soil pH at Sunam and Daeam were 3.8 and 4.6, respectively. When het­erotrophic and naphthalene-degrading bacteria were enumerated by most probable number (MPN) procedures at Sunam, the median values of heterotrophs growing at pH 7.0 and pH 4.0 were $5.3{\times}10^7\;and\;3.3{times}10^7$ MPN/g, whereas those of naphthalene-degraders were $5.6{\times}10^4\;and\;4.0{times}10^5$ MPN/g, respectively. While the medians of heterotrophs at Daeam were larger than those at Sunam, the concentrations of naphthalene-degraders were higher at Sunam compared to those at Daeam. From the MPN tubes and enrichment cultures, we obtained 17 isolates of naphthalene-degraders which were identified as Sphingomonas paucimobilis, Brevundimonas vesic­ularis, Burkholderia cepacia, Ralstonia pickettii, Pseudomanas fluorescens, and Chryseomonas luteola. Among them, 6 isolates showed higher naphthalene-degrading activity on minimal media of pH 4 compared to pH 7, whereas the extent of growth was not greater at pH 4 than at pH 7 when they were inoculated on nutrient-rich media. It is plausible that the pH may affect naphthalene-degrading activity of the isolates by changing fatty acid composition of bacterial membrane.

• Environmental and Resource Economics Review
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• v.22 no.1
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• pp.77-98
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• 2013

China, the world's largest $CO_2$ producer, is likely to be obligated to reduce greenhouse gas emissions under the post-Kyoto protocol. This paper estimates a Shephard input distance function for the Chinese fossil-fueled power generation sector to measure the shadow price of $CO_2$ emissions, technical efficiency, and indirect Morishima elasticities of substitution between inputs. Empirical results show that, on average, it costs approximately 3.2 US dollars per year to reduce $CO_2$ emissions by one ton over the period 1981-2009. This finding indicates that Chinese power sector is expected to benefit from selling emission permits to other countries such as Korea and Japan, given that our estimate for China is lower than the ones previous literatures estimated for the power sector in these countries. The maximum attainable average $CO_2$ reduction potential amounts to approximately 25 million tons per year by improving technical efficiency. Capital is substitutable with both coal and oil and capital is relatively more readily substituted for these fuels.

• Applied Chemistry for Engineering
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• v.24 no.1
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• pp.10-17
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• 2013

Heavy oil residue upgrading process was being used in conventional refinery process. Recently, as the importance of non conventional energy development is growing up, the commercial projects of heavy oil upgrading are getting more active than before. For having competitive business model in the resource competition, non conventional energy development should be considered as an important business strategy. In developing oil sands, extra heavy oil, and shale gas, canadian oil sands and extra heavy oil have great importance in substitution of conventional oil consumption. In oil sands development, the bitumen, which is extracted from oil sands, has great value after upgrading or refining process. Similar process is being used current conventional refinery process. The bitumen is highly viscous hydrocarbon. This bitumen includes impurities which can not be treated in conventional refinery process. As this reason, specified process is needed in bitumen or extra heavy oil upgrading process. Moreover, there will be additional specified facilities in the process of production, transportation and marketing. In oil sands, there are various kinds of commercial upgrading process. Extraction, dilution, coking and cracking method were being used commercially.

• Microbiology and Biotechnology Letters
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• v.33 no.3
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• pp.169-177
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• 2005

This study focuses on investigating roles of microorganisms in decontamination of reed rhizosphere in Sunchon Bay, Korea, which is considered one of the marsh and mud environment severely affected by human activities such as agriculture and fisheries. In general, the bay is known to play the role of the buffering zone to reduce the sudden impact or change by environmental stresses. In our initial efforts to elucidate the microbial functions in decontamination process in reed rhizosphere, pure bacteria capable of degrading aromatic hydrocarbons were isolated from reed (Phragmites communis) rhizosphere of Sunchon bay by enrichment culture using either benzene, toluene, ethylbenzene, or xylene (BTEX) as a sole source of carbon and energy. Measurement of the rates of BTEX degradation and cell growth during the incubation in BTEX media under several temperature conditions demonstrated maximized degradation of BTEX at $37^{\circ}C$ in both strains. Both strains were also resistant to all the heavy metals and antibiotics tested in this study, as well as they grew well at $42^{\circ}C$. Identification of the isolates based on 16S rRNA gene sequences, and a variety of phenotypic and morphologic properties revealed that the two strains capable of BTEX catabolism were among Microbacterium sp., and Rhodococcus sp. with over $95{\%}$ confidence, designated Microbacterium sp. EMB-1 and Rhodococcus sp. EMB-2, respectively This result suggested that in the rhizosphere of reed, one of major salt marsh plants they might play an important roles in decontamination process of reed rhizosphere contaminated with petroleum such as BTEX.

• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.119-125
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• 2014

This study evaluated the environmental impacts of a soil washing (SW) process, especially, we compared the on-site and off-site remediation of TPH-contaminated soil using green and sustainable remediation (GSR) tool. To assess relative contribution of each stage on environmental footprints in the entire soil washing process, we classified the process into four major stages: site foundation (stage I), excavation (stage II), separation & washing (stage III), and wastewater treatment (stage IV). In on-site SW process, the relative contribution of $CO_2$ emissions and energy consumption were 87.1% and 80.4%, respectively in stage I, and in off-site SW process, the relative contribution of $CO_2$ emissions and energy consumption were 82.7% and 80.5%, respectively in stage II. In conclusion, the major factor contributing environmental impact in the SW process were consumable materials including steel and stainless steel for washing equipment in on-site treatment and fuel consumption for transportation of soil in off-site treatment.