• Journal of Construction Engineering and Project Management
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• v.3 no.3
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• pp.1-9
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• 2013

Environmental problems like global warming have now become important issues that should be considered in all industries, including construction. In South Korea, many studies have been conducted to achieve the government's goals of reduction in environmental impacts. However, the research on buildings has only focused on CO2 emission as a research target despite the fact that other environmental impacts resulting from ozone depletion and acidification should also be considered, in addition to global warming. In this regard, this study attempted to propose assessment criteria and methods to evaluate the environmental performance of the structures from various aspects. The environmental impact category can be divided into global impacts, regional impacts, and local impacts. First, global impacts include global warming, ozone layer depletion, and abiotic resource depletion, while regional impacts include acidification, eutrophication, and photochemical oxidation. In addition, noise and vibration occurring in the building construction phase are defined as local impacts. The evaluation methods on the eight environmental impacts will be proposed after analyzing existing studies, and the methods representing each environmental load as monetary value will be presented. The methods presented in this study will present benefits that can be obtained through green buildings with a clear quantitative assessment on structures. Ultimately, it is expected that if the effects of green buildings are clearly presented through the findings of this study, the greening of structures will be actively expanded.

• Resources Recycling
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• v.27 no.1
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• pp.74-83
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• 2018

This study conducted the Life Cycle Assessment(LCA) on waste rubber recycling technology for recovering rubber product from the waste tires. Environmental impacts were assessed for the five categories of impacts: global warming, resource depletion, acidification, eutrophication, photochemical oxide production, and ozone layer depletion. When recycling 1ton of waste tire containing rubber, global warming impact was 1.77E+02 kg $CO_2-eq.$, resource depletion impact was 1.23E+00 kg Sb-eq., acidification impact was 5.92E-01 kg $SO_2-eq.$, eutrophication impact was 1.23E-01 kg $PO{_4}^{3-}-eq.$, photochemical oxide production impact was 3.42E-01 kg $C_2H_4-eq.$, and ozone layer depletion impact was 1.87E-04 kg CFC11-eq. In terms of overall environmental impacts, carbon, softener and electricity the greatest impact, so it is necessary to compare the environmental impacts of the raw materials to replace carbon and softener, and a method to reduce the filler usage in the process is needed. In addition, it is necessary to improve energy efficiency, change to low-energy sources, and apply renewable energy.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2188-2193
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• 2007

Since the use of CFCs and HCFCs refrigerants are to be restricted due to the depletion of ozone layer, this experiment applies the R134a gas to study the performance characteristic from the superheat control for improving the energy efficiency. The experiments are carried out for the condensing pressure of refrigeration system from 1.5 MPa to 1.6 MPa by 0.05 MPa and for superheat temperature from 0$^{\circ}C$ to 5$^{\circ}C$ by 1$^{\circ}C$ at each condensing pressure. As a result of experiment, when the superheat temperature is 1$^{\circ}C$ at each condensing pressure, the refrigeration system has the highest performance.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.524-529
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• 2001

Because of the ozone layer depletion and global wanning, new alternative refrigerants are being developed. Among them, HFC refrigerants are thought promising, but some European countries are arguing that these refrigerants are also harmful to the global wanning. Therefore, natural refrigerants should be considered as an eventual alternative in refrigerators and heat pumps. In the present study, the supercritical gas cooling process are computationally analysed by employing various turbulence models of carbon dioxide in a trans critical refrigeration cycle. The gas cooling process near the critical point experiences a drastic change in thermodynamic and transport properties, thus the heat transfer characteristics would be different from those of two or single phases. Based on the computational results, the correlations to estimate the near-critical heat transfer characteristics will are obtained.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1276-1281
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• 2004

Nowadays CFCs and HCFCs refrigerants are restricted because it cause depletion of ozone layer. Accordingly, this experiment apply the ammonia gas and not CFCs and HCFCs for refrigerant to study the performance characteristic from the superheat control and improve the energy efficiency from the high performance. The condensing pressure of refrigeration system is increased from 15.0bar to 16bar by 0.5bar and superheat temperature is increased from $0^{\circ}C$ to $10^{\circ}C$ by $1^{\circ}C$ at each condensing pressure. As the result of experiment, when the superheat temperature is $0^{\circ}C$ at each condensing pressure, the refrigeration system has the high performance.

• Textile Coloration and Finishing
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• v.13 no.5
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• pp.306-311
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• 2001

Natural colorants haute attracted much attention all over the world because of their non-hazardous nature. The world is becoming increasingly aware of environmental Issues, such as ozone layer depletion, water pollution and waste disposal problems. The use of synthetic dyestuffs for their synthesis and application in the dyeing industries has been criticized due to introduction of contaminants into the environment. This has led to the desire to turn to the traditional, and more natural way of life. In this study, the colorants of extract of Ginkgo biloba bark were analysed and their dyeing properties on silk, wool and cotton were studied. It was found that uv-visible absorption spectra of extract of Ginkgo biloba bark showed two strong absorption Peaks in the range of 240 ∼400 In. From the result of IR spectra, the major ingredient of extract of Gikgo biloba bark seems to be the flavon which is one of the flavonoid derivatives. Silk, wool, and cotton dyed with the extract of Ginkgo biloba bark showed a reddish yellow color. Their color differences were increased drastically with repetition of dyeing by three times.

• ALGAE
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• v.31 no.4
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• pp.403-414
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• 2016

The use of ionizing radiation and radioactive elements is becoming increasingly popular with the rapid developments in nuclear technology, radiotherapy, and radio diagnostic methods. However, ionizing radiation can directly or indirectly cause life-threatening complications such as cancer, radiation burns, and impaired immunity. Environmental contamination with radioactive elements and the depletion of ozone layer also contribute to the increased levels of radiation exposure. Radioprotective natural products have particularly received attention for their potential usefulness in counteracting radiation-induced damage because of their reduced toxicity compared with most drugs currently in use. Moreover, radioprotective substances are used as ingredients in cosmetic formulations in order to provide protection against ultraviolet radiation. Over the past few decades, the exploration of marine algae has revealed the presence of radioprotective phytochemicals, such as phlorotannins, polysaccharides, carotenoids and other compounds. With their promising radioprotective effects, marine algae could be a future source for discovering potential radioprotective substances for development as useful in therapeutics.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.8
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• pp.756-761
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• 2004

Since the use of CFC and HCFC refrigerants are to be restricted due to the depletion of ozone layer, this experiment applies the NH$_3$ gas to study the performance characteristics from the superheat control for improving the energy efficiency. The experiments are carried out for the condensing pressure of refrigeration system from 14.5 bar to 16.0 bar by 0.5 bar and for superheat temperature from $0^{\circ}C$ to 1$0^{\circ}C$ by 1$^{\circ}C$ at each condensing pressure. As a result of experiment, when the superheat temperature is 1$^{\circ}C$ at each condensing pressure, the refrigeration system has the highest performance.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1334-1339
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• 2004

Nowadays CFCs and HCFCs refrigerants are restricted because it cause depletion of ozone layer. Accordingly, this experiment apply the $NH_3$ gas and not CFCs and HCFCs for refrigerant to study the performance characteristic from the superheat control and improve the energy efficiency from the high performance. The condensing pressure of refrigeration system is increased from 14.5bar to 16bar by 0.5bar and superheat temperature is increased from $0^{\circ}C$ to $10^{\circ}C$ by $1^{\circ}C$ at each condensing pressure. As the result of experiment, when the superheat temperature is $1^{\circ}C$ at each condensing pressure, the refrigeration system has the high performance.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.60-65
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• 2005

Nowadays HCFCs refrigerant are restricted because it cause depletion of ozone layer. However, natural gases such as ammonia as an organic compound, propane and propylene as hydrocarbon are easy and cheap to obtain as well as environmental. Accordingly, this experiment apply the $NH_3$ and R22 to study the performance characteristic from the superheat control and compare the energy efficiency of two refrigerants from the high performance. The condensing pressure of refrigeration system is increased from 15bar to 16bar and degree of superheat is increased from 0 to $10^{\circ}C$ at each condensing pressure. As the result of experiment, when comparing the each COP, we knew the $NH_3$ is suitable as the alternative refrigerant of the R22.