• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.351-357
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• 2006

Recently there is increasing the flow of hazardous chemical substances caused by industrial waste waters into a main river. It is needed to make the high treatment in drinking water treatment plants for reducing a health risk. Therefore, the monitoring of trace hazardous chemical substances by the industrial waste water inflow is available increasing economical efficiency of river management as well as reduction of risk. In this study, the most important substance among numerical and quantitative trace hazardous chemicals is Hexachlorobutadiene in an effluent of industrial wastes. However all items of GroupII which was included with semiconductor, electricity/electron and metal assemble was not detected. It means that we must consider the characteristics and behavior of load pollutants to water resources to select monitoring items. That was called 'preparatory monitoring'. We can reduce an economical consumption as well as risks from these pollutants using the preparatory monitoring.

• Resources Recycling
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• v.32 no.2
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• pp.12-18
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• 2023

In 2018, the demand for silver (referred to as Ag) in the electrical and electronics sector was 249 million tons. The demand stood at 81 million tons in the solar module production sector. Currently, due to the rapid increase in solar module installation, the demand for silver is increasing drastically in Korea. However, Korea's natural metal resources and reserves are insufficient in comparison to their consumption, and the domestic silver ore self-sufficiency rate was as low as 2.2% as of 2021. This implies that a recycling technology is necessary to recover valuable metal resources contained in the waste plating solution generated in the metal industry. Therefore, this study compared and analyzed, the results of the impact evaluation through life cycle assessment according to an improvement in the process of recovery of valuable metals in the waste plating solution. The process improvement resulted in reducing GWP (Global Warming Potential) and ADP(Abiotic Depletion Potential) by 50% and 67%, respectively. The GWP of electricity and industrial water was reduced by 98% and 93%, respectively, which significantly contributed to the minimization of energy and water consumption. Thus, the improvement in recycling technology has a high potential to reduce chemical and energy use and improve resource productivity in the urban mining industry.

• Environmental and Resource Economics Review
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• v.24 no.3
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• pp.573-605
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• 2015

This study proposed scenarios of tax reform regarding taxation on bituminous coal for power generation since July 2015 and July 2014, estimated its impact on SMP, settlement price, tax revenue from year 2015 to year 2029. These scenarios are compared with those of the standard scenario. To estimate them, the power system simulation was performed based on the government plan, such as demand supply program and the customized model to fit Korea's power system and operation. Imposing a tax on bituminous coal for power generation while maintaining tax neutrality reducing tax rate on LNG, the short-term SMP is lowered than the one of the standard scenario. Because the cost of nuclear power generation is still smaller than costs of other power generation, and the nuclear power generation rarely determines SMPs, the taxation impact on SMP is almost nonexistent. Thus it is difficult to slow down the electrification of energy consumption due to taxation of power plant bituminous coal in the short term, if SMP and settlement price is closely related. However, in the mid or long term, if the capacity of coal power plant is to be big enough, the taxation of power plant bituminous coal will increase SMP. Therefore, if the tax reform is made to impose on power plant bituminous coal in the short term, and if the tax rate on LNG is to be revised after implementing big enough new power plants using bituminous coal, the energy demand would be reduced by increasing electric charges through energy tax reform. Both imposing a tax on power plant bituminous coal and reducing tax rate on LNG increase settlement price, higher than the one of the standard scenario. In the mid or long term, the utilization of LNG complex power plants would be lower due to an expansion of generating plants, and thus, the tax rate on LNG would not affect on settlement price. Unlike to the impact on SMP, the taxation on nuclear power plants has increased settlement price due to the impact of settlement adjustment factor. The net impact of energy taxation will depend upon the level of offset between settlement price decrease by the expansion of energy supply and settlement price increase by imposing a tax on energy. Among taxable items, the tax on nuclear power plants will increase the most of additional tax revenue. Considering tax revenues in accordance with energy tax scenarios, the higher the tax rate on bituminous coal and nuclear power, the bigger the tax revenues.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.3
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• pp.167-173
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• 2011

The Effects of external resistance on electrical properties such as current density, power density and coulombic efficiency were investigated in two-chamber type MFCs using a ferricyanide as reducing agent. A stable electricity was produced when a constant time elapsed after innoculation of mixed cultures into the anode compartment; voltages from 0.13 to 0.16 V was measured at $50{\Omega}$ of external resistance. When the external resistance was increased, the current density decreased and the power density rapidly increased and then slowly decreased. Big variation of electrical properties was observed in high-current density region due to the concentration loss related with substrate consumption in repeated experiments changing the external resistance. The maximum power density ($175.8mW/m^2$) and coulombic efficiency (46.1%) were obtained at $100{\Omega}$ of the external resistance which is nearest with the internal resistance ($134{\Omega}$) of MFC system.

• Resources Recycling
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• v.31 no.1
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• pp.37-45
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• 2022

The development of the electrical, electronic, and telecommunication industries has increased the share of electricity in total energy consumption. With the enforcement of the Act on the Promotion of the Development, Use, and Diffusion of New and Renewable Energy in 2021, the mandatory supply ratio of new and renewable energy is expected to expand, and the amount of waste cables generated in the stage of replacing and discarding cables used in the industry is also expected to increase. The purpose of this study was to quantify the environmental burden of waste cable recycling through the life cycle assessment (LCA) method. The results showed that the higher the amount of glue contained in the waste cable, the greater was the amount of fine dust and greenhouse gases generated. In addition, by assigning weights to 10 environmental burden items, it was confirmed that the marine aquatic eco-toxicity potential (MAETP) and human toxicity potential (HTP) had the greatest environmental burden. The main causes were identified as heptane and ethanol, which were the glue contained in the waste cable and the cleaning solutions used to remove them. Therefore, it is necessary to refrain from using glue in the cable production process and reduce the environmental burden by reducing the use of waste cable cleaning solutions used in the recycling process or using alternative materials.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.6
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• pp.85-96
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• 2018

Developed nations have implemented various policies to reduce greenhouse gases since the 1997 Kyoto Protocol in order to minimize the effects of global warming. Korea should also reduce energy consumption in the industrial sector, and the transportation and building sectors in order to achieve its greenhouse gas reduction target of 37 percent compared to the Business As Usual levels. The government implements various laws and regulations for reducing energy consumption. To reduce energy consumption in the building sector, in particular, the Energy Conservation Design Standards are enforced according to the 'Enforcement Support for Green Building Construction'. The amount of electricity used to maintain room temperature at $28^{\circ}C$ in these buildings have a 30% reduction (measured on the walls and rooftop) in power usage compared to buildings not required to meet these standards. Although the effect of these energy savings on landscaping is proven, this demonstration is not effective for energy saving since it is not a suitable method for the 'Energy Saving Design Standards of Buildings'. For landscaping to be effective as far as a component of energy reduction, the perfusion rate of the building should be calculated based on the thermal conductivity of the component materials for the energy saving designs with respect to the basis of Article 14 of the Green Building Act. Therefore, the purpose of this study is to ensure that the planting-based mats currently being widely used in the landscape industry can have insulating performance suitable for the 'Energy Saving Design Standards' of Buildings according to the 'Enable Green Building Construction Methods'.

• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.79-87
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• 2012

This research was conducted to obtain basic data with regard to the heating performance that would be produced by installing an aluminum hot water pipe inside the greenhouse with the goal of reducing the heating energy in greenhouse. The research results are summarized as follows. The degree of difference in relation to the temperature by height within the greenhouse during the entire experiment was significant - within the range of 4.0~$7.0^{\circ}C$. The temperature difference between incoming and outgoing water was about $3.3^{\circ}C$ greater when FCU was activated compared to when it was not activated. Meanwhile, the amount of energy consumed increased about 36.2~40.1%. The amount of pyrexia per hour also increased by 44.6~52.0%. During the experiment period, circulated flux was within the range of 0.48~$0.49L{\cdot}s^{-1}$ while average fluid speed was 1.53~$1.56m{\cdot}s^{-1}$. The average temperature difference between incoming and outgoing water was 6.24~$11.50^{\circ}C$. The amount of heating value by each set temperature within the minimum outdoor temperature range of -14.0~$-0.6^{\circ}C$ was 135,930~307,150 kcal, and the range was within the 9,610~$19,630kcal{\cdot}h^{-1}$ per hour. This demonstrated that about 23~53% heating energy of the maximum heating load could be supplied. Total radiating value and amount of energy consumed were 2,548,306 kcal and 3,075.7 kWh, respectively. When heating takes place using oil, which is a fossil fuel, the total amount of light oil consumed was 281.6 L while the cost was 321,000 won. When the electricity cost for farms is applied, the total cost was about 110,730 won, which is about 33.5% of the cost required compared to oil consumption. The temperature at in the experiment area was about 8.3~$14.6^{\circ}C$ higher compared to that of the control area.