• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.4
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• pp.358-383
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• 2015

The concept of 'carbon footprint' has been developed as a means of quantifying the specific emissions of the greenhouse gases (GHGs) that cause global warming. Although there are still neither clear definitions of the term nor rules for units or the scope of its estimation, it is broadly accepted that the carbon footprint is the total amount of GHGs, expressed as $CO_2$ equivalents, emitted into the atmosphere directly or indirectly at all processes of the production by an individual or organization. According to the ISO/TS 14067, the carbon footprint of a product is calculated by multiplying the units of activity of processes that emit GHGs by emission factor of the processes, and by summing them up. Based on this, 'carbon labelling' system has been implemented in various ways over the world to provide consumers the opportunities of comparison and choice, and to encourage voluntary activities of producers to reduce GHG emissions. In the agricultural sector, as a judgment basis to help purchaser with ethical consumption, 'low-carbon agricultural and livestock products certification' system is expected to have more utilization value. In this process, the 'cradle to gate' approach (which excludes stages for usage and disposal) is mainly used to set the boundaries of the life cycle assessment for agricultural products. The estimation of carbon footprint for the entire agricultural and forestry sector should take both removals and emissions into account in the "National Greenhouse Gas Inventory Report". The carbon accumulation in the biomass of perennial trees in cropland should be considered also to reduce the total GHG emissions. In order to accomplish this, tower-based flux measurements can be used, which provide a direct quantification of $CO_2$ exchange during the entire life cycle. Carbon footprint information can be combined with other indicators to develop more holistic assessment indicators for sustainable agricultural and forestry ecosystems.

• Journal of the Korea Organic Resources Recycling Association
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• v.23 no.2
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• pp.36-46
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• 2015

Integration of crop-livestock farming has been a problem-solving mode for abatement of environmental pollution and recovery of resources in recent years. The objectives of this study were 1) to suggest the customized integration of crop-livestock farming model reflecting the regional characteristics through in-depth analysis of case study and 2) to analyze the livestock nutrients flow in terms of three primary elements as nitrogen(N), phosphorous(P), and potassium(K). The personal interview and survey were carried out in 2012 for a total of 161 farms from four different regions(NS, NW, JJ, YC) in South Korea. The mass balance analysis was used to suggest and evaluate the models for two sites(JJ and YC). The results showed that NS and NW sites produced relatively more livestock manure than the sites of YC and JJ because of the regional differences in livestock numbers and urbanization. The models were suggested for the site JJ and site YC, and 'two track model(energy and resource recovery)' and 'dispersal type model' were assigned respectively. For the nutrient flows, the releasing P and K with new models had increased up to 7%, while N release had decreased down to 15% in both YC and JJ sites compared to the present treatment system. Estimated value showed that there was oversupply of N (719 ton/yr) and $P_2O_5$ (1,269 ton/yr) in YC and deficiency of N (671 ton/yr) and excessive $P_2O_5$ (32 ton/yr) in JJ respectively. Therefore, P runoff has to be considered an eutrophication occurs in rural small stream when an integration of crop-livestock farm system is applied into both sites.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.656-664
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• 2010

We investigated the levels and distribution patterns of 16 priority polycyclic aromatic hydrocarbons (PAHs), 12 Coplanar polychlorinated biphenyls (Co-PCBs) and organochlorine pesticides (OCPs) in the surface sediments from the Nakdong river basin, Korea. The levels of 16 PAHs and 12 Co-PCBs in the river sediment samples ranged from not detected (N.D.)~969.3 ng/g-dry, 4.2~7716.5 pg/g-dry (0.0~10.1 pg-TEQ/g-dry), respectively. Also, the levels of 16 PAHs were from 5.8~2987.2 ng/g-dry and 4.3~461.1 pg/g-dry (0.0~0.6 pg-TEQ/g-dry) for 12 Co-PCBs in the lake sediment samples. Only dichloro-diphenyl-trichloroethane (DDT) were detected among target OCPs and the concentration ranged from N.D.~1.5 ng/g-dry in the river sediment samples. These contamination levels were far below the guideline values suggested for environmental quality assessment. Low molecular weight PAHs were dominant in the river sediment samples, while middle and high molecular weight PAHs were dominant among 16 PAHs in the lake sediment samples. PCB-118 and PCB-105 were predominant congeners in the sediment, which were similar to the results obtained from previous studies. With these results, the assessment of potential sources of PAHs and Co-PCBs contamination in the sediments of the Nakdong river basin was performed. The pyrogenic-PAHs originated from combustion of fossil fuel and biomass were related with the PAHs contribution in most of the sediment samples, and Co-PCBs in the sediment samples were related with commercial PCB products.

• Journal of the Korean Wood Science and Technology
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• v.43 no.3
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• pp.374-380
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• 2015

The quality characteristics of the woodpellet manufactured from two domestic pines (Pinus densiflora S. et Z. and Pinus rigida Mill.) were investigated for the efficient energy use of woody biomass resources. Properties of woodpellets such as moisture content, heating value, ash content, apparent density and durability were determined by using the standard test method of woodpellets of Korea Forest Research Institute (KFRI) and elemental analysis. The results of elemental analysis for C, H, O and N showed 61.42% carbon, 5.56% hydrogen, 32.87% oxygen, and 0.15% nitrogen for Pinus densiflora S. et Z. and 61.03% carbon, 5.96% hydrogen, 32.83% oxygen, and 0.18% nitrogen for Pinus rigida Mill. No significant difference between Pinus densiflora S. et Z. and Pinus rigida Mill was observed on elemental analysis. Heating values of each woodpellet were ranged from 19.00 to 19.42 MJ/kg which satisfied the first grade quality standard (${\geq}18.0MJ/kg$) by KFRI. The ash contents of woodpellet were slightly different between Pinus densiflora S. et Z. and Pinus rigida Mill., and satisfied the first grade quality standard (${\leq}0.7%$) by KFRI. Apparent density of woodpellet (Pinus densiflora S. et Z.) was passed the first grade standard level (${\geq}640kg/m^3$), and woodpellets from Pinus rigida Mill. satisfied the second grade quality of the standard. The moisture contents of each woodpellet were satisfied by the first grade quality standard (${\leq}10%$). The durability of woodpellet (Pinus densiflora S. et Z.) was passed the third grade level (${\geq}95%$), but Pinus rigida Mill. woodpellet was insufficient to satisfy the quality standard.

• Journal of the Korean Wood Science and Technology
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• v.46 no.1
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• pp.17-28
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• 2018

In this study, catalytic activation using sulfuric acid lignin (SAL), the condensed solid by-product from saccharification process, with potassium hydroxide at $750^{\circ}C$ for 1 h in order to investigate its potential to nanoporous carbon In this study, catalytic activation using sulfuric acid lignin (SAL), the condensed solid by-product from saccharification process, with potassium hydroxide at $750^{\circ}C$ for 1 h in order to investigate its potential to nanoporous carbon material. Comparison study was also conducted by production of activated carbon from coconut shell (CCNS), Pinus, and Avicel, and each activated carbon was characterized by chemical composition, Raman spectroscopy, SEM analysis, and BET analysis. The amount of solid residue after thermogravimetric analysis of biomass samples at the final temperature of $750^{\circ}C$ was SAL > CCNS > Pinus > Avicel, which was the same as the order of activated carbon yields after catalytic activation. Specifically, SAL-derived activated carbon showed the highest value of carbon content (91.0%) and $I_d/I_g$ peak ratio (4.2), indicating that amorphous large aromatic structure layer was formed with high carbon fixation. In addition, the largest changes was observed in SAL with the maximum BET specific surface area and pore volume of $2341m^2/g$ and $1.270cm^3/g$, respectively. Furthermore, the adsorption test for three kinds of organic pollutants (phenol, 2,4-Dichlorophenoxyacetic acid, and carbofuran) were conducted, and an excellent adsorption capacity more than 90 mg/g for all activated carbon was determined using 100 ppm of the standard solution. Therefore, SAL, a condensed structure, can be used not only as a nanoporous carbon material with high specific surface area but also as a biosorbent applied to a carbon filter for remediation of organic pollutants in future.

• Journal of Korean Society of Forest Science
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• v.103 no.4
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• pp.593-598
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• 2014

In this study, we developed the carbon emission factors for 4 major species of warm-temperate region in Korea, and tried to provide their carbon emissions and removals estimates using these carbon emission factors. We selected Castanopsis cuspidata, Camellia japonica, Quercus acuta and Quercus glauca as target species and derived their carbon emission factors. The basic wood density that serve as one of the carbon emission factors were 0.583 for Castanopsis cuspidata, 0.657 for Camellia japonica, 0.833 for Quercus acuta and 0.763 for Quercus glauca and their uncertainties ranged from 5.3 to 17.9%. Biomass expansion factors were calculated as well: 1.386 for Castanopsis cuspidata, 2.621 for Camellia japonica, 1.701 for Quercus acuta and 2.123 for Quercus glauca and associated uncertainties varied from 14.7 to 30.5%. Lastly root-shoot ratios for each species were also determined: 0.454 for Castanopsis cuspidata, 0.356 for Camellia japonica, 0.191 for Quercus acuta and 0.299 for Quercus glauca with the uncertainties lying within a range from 19.8 to 35.7%. These three carbon emission factors including basic wood density had the uncertainties of less than 40% recommended by FAO. Therefore the application of country-specific emission factors seemed to provide quite accurate estimates of carbon emissions and removals. The estimation of the carbon stored in the 4 species were also conducted which amounted to $186.10tCO_2/ha$ for Castanopsis cuspidata, $280.63tCO_2/ha$ for Camellia japonica, $344.04tCO_2/ha$ for Quercus acuta and $278.91tCO_2/ha$ for Quercus glauca and their annual carbon removals were $6.65tCO_2/ha/yr$, $6.25tCO_2/ha/yr$, $11.70tCO_2/ha/yr$ and $12.29tCO_2/ha/yr$, respectively. This systematic assessment of forest resources can be a reliable source of information for managing evergreen broadleaved forest in warm temperate regions and thus serve as useful data for effective decision-making to address vegetation zone shifts due to climate change.

• Korean Chemical Engineering Research
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• v.55 no.3
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• pp.436-442
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• 2017

Fischer-Tropsch synthesis is the technology of converting a syngas (CO+$H_2$) derived from such as coal, natural gas and biomass into a hydrocarbon using a catalyst. The catalyst used in the Fischer-Tropsch synthesis consists of active metal, promoter and support. The types of these components and composition affect the reaction activity and product selectivity. In this study, we manufactured an iron catalyst using ${\gamma}-Al_2O_3/SiO_2$ mixed support (100/0 wt%, 75/25 wt%, 50/50 wt%, 25/75 wt%, 0/100 wt%) by an impregnation method to investigate how the composition of ${\gamma}-Al_2O_3/SiO_2$ mixed support effects on the reaction activity and product selectivity. The physical properties of catalyst were analyzed by $N_2$ physical adsorption and X-Ray diffraction method. The Fischer-Tropsch synthesis was conducted at $300^{\circ}C$, 20bar in a fixed bed reactor for 60h. According to the results of the $N_2$ physical adsorption analysis, the BET surface area decreases as the composition of ${\gamma}-Al_2O_3$ decreases, and the pore volume and pore average diameter increase as the composition of ${\gamma}-Al_2O_3$ decreases except for the composition of ${\gamma}-Al_2O_3/SiO_2$ of 50/50 wt%. By the results of the X-Ray diffraction analysis, the particle size of ${\alpha}-Fe_2O_3$ decreases as the composition of ${\gamma}-Al_2O_3$ decreases. As a result of the Fischer-Tropsch synthesis, the CO conversion decreases as the composition of ${\gamma}-Al_2O_3$ decreases, and the selectivity of C1-C4 decreases until the composition of ${\gamma}-Al_2O_3$ was 25 wt%. In contrast, the selectivity of C5+ increases until the composition of ${\gamma}-Al_2O_3$ is 25 wt%.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.31-40
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• 2014

The Korean government made the 2nd Energy Basic Plan to achieve 11% of new and renewable energies distribution rate until 2035 as a response to cope with international discussion about greenhouse gas emission reduction. Renewable energies include solar thermal, photovoltaic, bioenergy, wind power, small hydropower, geothermal energy, ocean energy, and waste energy. New energies contain fuel cells, coal gasification and liquefaction, and hydrogen. As public and private investment to enhance the distribution of new and renewable energies, it is necessary to clarify the economic effects of the new and renewable energies sector. To the end, this study attempts to apply an input-output analysis and analyze the economic effects of new and renewable energies sector using 2012 input-output table. Three topics are dealt with. First, production-inducing effect, value-added creation effect, and employment-inducing effect are quantified based on demand-driven model. Second, supply shortage effects are analyzed employing supply-driven model. Lastly, price pervasive effects are investigated applying Leontief price model. The results of this analysis are as follows. First, one won of production or investment in new and renewable energies sector induces 2.1776 won of production and 0.7080 won of value-added. Moreover, the employment-inducing effect of one billion won of production or investment in new and renewable energies sector is estimated to be 9.0337 persons. Second, production shortage cost from one won of supply failure in new and renewable energies sector is calculated to be 1.6314 won, which is not small. Third, the impact of the 10% increase in new and renewable energies rate on the general price level is computed to be 0.0123%, which is small. This information can be utilized in forecasting the economic effects of new and renewable energies sector.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.1
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• pp.1-15
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• 2016

Annual litterfall production and leaf area index (LAI, $m^2/m^2$) were estimated using litter traps in Gwangneung, Mt. Taewha and Mt. Gariwang. Annual total litter fall production including branch, bark, others was the highest in Gwangneung($7497.3{\pm}326.5kg/ha/yr$), which had the highest basal area at late successional stage, and followed by Mt. Taewha($5929.1{\pm}225.8kg/ha/yr$) and Mt. Gariwang($3,210.1{\pm}220.1kg/ha/yr$). Mt. Gariwang had the lowest litterfall production due to high elevation and short growing season even with the higher stand density and basal area than Mt. Taewha. Similarly, LAI, which was calculated by multiplying the mass of leaf litter with specific leaf area, was the highest in Gwangneung($5.99{\pm}0.69$) and followed by Mt. Taewha($5.20{\pm}0.24$) and Mt. Gariwang($4.06{\pm}0.42$) and the upper canopy species had the highest leaf area index in every sites (Gwangneung : 4.72, Mt. Taewha : 3.08, Mt. Gariwang : 2.19). However, species specific LAI estimation based on the relationship between basal area and leaf area was limited due to upper canopy species non-proportionality of basal area with LAI. In addition, the comparison between direct and indirect LAI measurement showed the importance of canopy clumping, especially at high density. Our study emphasized the necessity of direct LAI measurement using litter fall traps especially at temperate deciduous forest with diverse species.

• Journal of Korea Water Resources Association
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• v.50 no.11
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• pp.715-723
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• 2017

Extracellular Polymeric Substances (EPS) in the water environment assemble fine, colloidal particles, such as clays, microorganisms and biomass, in large flocs, which are eventually subject to sedimentation and deposition and determine water/sediment quality and quantity. This study hence aimed to investigate the way that water and colloidal chemistry affects EPS-mediated flocculation of colloidal particles, using a jar-test experiment. Especially, ionic strength, divalent cation and humic substances concentrations were selected as experimental variables in the jar-test experiments, to elucidate their effects on EPS-mediated flocculation. A higher ionic strength increased flocculation capability, reducing electrostatic repulsion between EPS-attached colloidal particles and enhancing particle aggregation. 0.1 M NaCl ionic strength had higher flocculation capability, with 3 times larger floc size and 2.5 times lower suspended solid concentration, than 0.001 M NaCl. Divalent cations, such as $Ca^{2+}$, built divalent cationic bridges between colloidal particles and EPS (i.e., $colloid-Ca^{2+}-EPS$ or $EPS-Ca^{2+}-EPS$) and hence made colloidal particles to build into large, settelable flocs. A small $Ca^{2+}$ concentration enhanced flocculation capability, reducing suspended solid concentration 20 times lower than the initial dosed concentration. However, humic substances, adsorbed on colloidal particles, reduced flocculation, because they blocked EPS adsorption on colloidal particles and increased negative charges and electrostatic repulsion of colloidal particles. Suspended solid concentration in the tests with humic substances remained as high as the initial dosed concentration, indicating stabilization rather than flocculation. Findings about EPS-mediated flocculation in this research will be used for better understanding the fate and transport of colloidal particles in the water environment and for developing the best management practices for water/sediment quality.