• Asian Journal of Atmospheric Environment
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• v.5 no.3
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• pp.189-195
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• 2011

Korea-specific GHG emissions should be estimated correctly in order to ensure effective measurement of climate change variables. The use of country-specific data that reflects fuel and technology characteristics is needed for accurate GHG emissions estimation. Oxidation factors are used to convert existing data into equivalent GHG emissions, and changes in these oxidation factors are directly related to changes in emissions. As such, the oxidation factor is one of the most important variables in using country-specific data to determine GHG emissions. In this study, the oxidation factor of bituminous coal in large scale boilers was estimated using 4,527 data points sampled from eight large-scale boilers that had been using bituminous coal for two years. The average oxidation factor was determined to be 0.997, which is lower than the oxidation factor of 1 that is recommended by the IPCC G/L for large scale boilers when estimating national GHG emissions. However, an oxidation factor less than 1 is assumed for fluidized bed boilers, internal combustion engines, and other small-scale boilers. Accordingly, studies on oxidation factor estimation should be continued to allow for accurate estimation of GHG emissions.

• Journal of the Korea Institute of Building Construction
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• v.15 no.2
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• pp.193-199
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• 2015

As a solution of both environmental issue of reducing carbon dioxide emission and sustainable issue of exhausting natural resources, in concrete industry, many research on recycling various by-products or industrial wastes as the concrete materials has been conducted. The aim of this research is feasibility analysis of additional reaction with ordinary Portland cement and flue gas desulfurization gypsum based on the blast furnace slag and recycled fine aggregate based mortar to achieve the normal strength range. Consequently, in the case of mortar replaced 10% FGD and 30% OPC for BS, 80% of plain OPC mortar's compressive strength was achieved. Furthermore, when the water-to-binder ratio is decreased to keep the practically similar level of flow, it is expected to be achieve the equivalent compressive strength to plain OPC mortar.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.3
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• pp.138-144
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• 2017

In order to reduce carbon dioxide emission in construction industry, less amount of cement use can be one of the alternatives to manufacture concrete. One of the non-sintered construction materials are limestone, which is the raw material to manufacture ordinary Portland cement(OPC). A large amount of limestone have already been used as binders such as blended cement in Europe and US. Even European countries were already established the standard of blended cement, where the limestone can be used up to 35 percent. In this study, experimental researches were conducted to investigate the effects of limestone replacement on the mechanical properties and durability of concrete with 15%, 25% and 35% of limestone substitution to use limestone in blended cement. 15 percent use of limestone in blended cement developed equivalent or even higher compressive strengths compared to Plain mixture. Porosity of limestone cement with 15 percent substitution was much lower than Plain mixture. Most durability tests such as concrete carbonation, freeze-thaw cycle and drying shrinkage strains were conducted to evaluate long-term performance, and the test results indicated that 15 percent of limestone use did not significantly influence on the concrete durability compared with plain concrete.

• Journal of Preventive Medicine and Public Health
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• v.6 no.1
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• pp.27-41
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• 1973

In order to provide some basic data for the control of air and water pollution in Korea, the authors have estimated the amount of air and water pollutants emitted from industries which are employed over 20 employees. This study have done from July 1, 1972 to the end of March 1973. The results are as followings; 1. Total number of establishments with over 20 employees is 5,197 in Korea and the largest group establishments was the manufacturing of textiles with 1,363 establishments (26.2%). 2. By order of number of employees it was observed that there 2,800 industries with 20-59(53.9%) employees, 1,101 with 50-99 (21.2%), 571 with 100-199 (11.0%), 501 with 200-499 (9.6%) and 225 with over 500 (4.3%) respectively. 3. By order of regional distribution, it was observed that there were 2,257 industries in Seoul (43.2%) and 736 industries in Pusan(14.2%). 4. Industrial coal consumption was 596,154 M/T in 1972, but it' 11 be 315,000 M/T in 1980. Fuel consumption was 4,972,000 K1 in 1972, and estimated volume will be 19,370,000 K1 in 1980. 5. Total amounts of air polutants entitled from industries by fuel combustion were sulfur oxides 79,459 tons, carbon monoxide 33,908 tons, particulate 31,304 tons and hydrocarbon 30,280 tons in 1972 but in 1990 there will be sulfur oxides 1,010,474 tons, nitrogen oxides 204,575 tons, carbon monoxide 68,014 tons, particulate 64,820 tons and hydrocarbon 67,622 tons, respectively. 6. Annual emitted air pollutants through the working processes were sulfur oxides 91,250 tons and nitrogen oxides 32,485 tons in 1972, but sulfur oxides 118,625 tons and nitrogen oxides 42,555 tons will be present in 1980, respectively. 7. Annual emitted air pollutants by national unit area amounted to $0.77ton/km^2/year$ in 1965 and $14.7ton/km^2/year$ in 1980. 8. Total industrial wastes from all industries in Korea were estimated at 810,360 tons/day in 1972; manufacturing of chemicals and plastic products showed the highest amount of wastes at 470,000 tons/day. 9. The amounts of water pollutants due to industrial wastes were the B.O.D., 471.5 tons/day, suspended solid 331.5 tons/day, CN, 2.3 tons/day, and Cr. 3.4 tons/day in 1972, but it might be evident of a B.O.D. of 3,388 tons/day, suspended solid 2,544 tons/day, CN 20.1 tons/day, and 26.5 tone/day in 1990. 10. Total population equivalent of B.O.D. was 943,000 in 1972, and the estimated value in 1950 will be 6,780,000.

• Journal of Environmental Science International
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• v.22 no.2
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• pp.139-149
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• 2013

Anthropogenic increases in greenhouse gas concentrations, primarily through radiative forcing from carbon dioxide, continue to challenge earth's climate. This study quantified $CO_2$ storage and uptake by dominant forest types and age classes in the middle region of Korea. In addition, the role of forest landscapes in reducing atmospheric $CO_2$ against $CO_2$ emissions based on energy consumption was evaluated. Mean $CO_2$ storage and uptake per unit area by woody plants for three forest types and four age classes were estimated applying regression equations derived to quantify $CO_2$ storage and uptake per tree; and computations per soil unit area were also performed. Total $CO_2$ storage and uptake by forest landscapes were estimated by extrapolating $CO_2$ storage and uptake per unit area. Results indicated mean $CO_2$ storage per unit area by woody plants and soils was higher in older age classes for the same forest types, and higher in broadleaved than coniferous forests for the same age classes, with the exception of age class II (11-20 years). $CO_2$ storage by broadleaved forests of age class V (41-50 years) averaged 662.0 t/ha (US$331.0 hundred/ha), highest for all forest types and age classes evaluated. Overall, an increased mean $CO_2$ uptake per unit area by woody plants was evident for older age classes for the same forest types. However, decreased $CO_2$ uptake by broadleaved forests at age class V was observed, compared to classes III and IV with an average of 27.9 t/ha/yr (US$14.0 hundred/ha/yr). Total $CO_2$ storage by woody plants and soils in the study area was equivalent to 3.4 times the annual $CO_2$ emissions, and woody plants annually offset the $CO_2$ emissions by 17.7%. The important roles of plants and soils were associated with 39.1% of total forest area in South Korea, and $CO_2$ emissions comprised 62.2% of the total population. Therefore, development of forest lands may change $CO_2$ sinks into sources. Forest landscape management strategies were explored to maintain or improve forest roles in reducing atmospheric $CO_2$ levels.