• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.3
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• pp.9-24
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• 2022

Currently, a vast amount of hydrologic data is accumulated in real-time through automatic water level measuring instruments in agricultural reservoirs. At the same time, false and missing data points are also increasing. The applicability and reliability of quality control of hydrological data must be secured for efficient agricultural water management through calculation of water supply and disaster management. Considering the characteristics of irregularities in hydrological data caused by irrigation water usage and rainfall pattern, the Korea Rural Community Corporation is currently applying the Hampel filter as a water level data quality management method. This method uses window size as a key parameter, and if window size is large, distortion of data may occur and if window size is small, many outliers are not removed which reduces the reliability of the corrected data. Thus, selection of the optimal window size for individual reservoir is required. To ensure reliability, we compared and analyzed the RMSE (Root Mean Square Error) and NSE (Nash-Sutcliffe model efficiency coefficient) of the corrected data and the daily water level of the RIMS (Rural Infrastructure Management System) data, and the automatic outlier detection standards used by the Ministry of Environment. To select the optimal window size, we used the classification performance evaluation index of the error matrix and the rainfall data of the irrigation period, showing the optimal values at 3 h. The efficient reservoir automatic calibration technique can reduce manpower and time required for manual calibration, and is expected to improve the reliability of water level data and the value of water resources.

• Journal of The Korean Society of Agricultural Engineers
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• v.63 no.5
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• pp.13-25
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• 2021

The particulate matters (PM₁₀ and PM_2.5) and ammonia emitted from livestock farms as dispersed to urban and residential areas can increase the public's concern over the health problem, social conflicts, and air quality. Understanding the atmospheric dispersion of such matters is important to prevent the problems for the regulatory purposes. In this study, AERMOD modeling was performed to predict the dispersion of livestock particulate matters and ammonia in Gwangju metropolitan city and five surrounding cities. The five cities were divided into 40 sub-zones to model the area-based emissions which varied with the number of livestock farms, species and growth stages of the animals. As a result, the concentrations of PM₁₀, PM_2.5 and ammonia resulted from livestock farms located in the surrounding cities were 2.00 ㎍ m^-3, 0.30 ㎍ m^-3 and 0.04 ppm in the southwestern part of Gwangju based on the average concentration of 1 hour. These values accounted for 0.7% of PM₁₀ concentration, 0.5% of PM_2.5 concentration, and 0.4% of the ammonia concentration in Gwangju, contributing to a small amount of air pollution compared to other sources. As preventive measures, the plantation was applied to high emission source areas to reduce particulate matters and ammonia emissions by 35% and 31%, respectively, and resulted in decrease of the area of influence by 57% for particulate matters and 59% for ammonia.

• Journal of The Korean Society of Agricultural Engineers
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• v.63 no.6
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• pp.117-129
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• 2021

The movement of animals is one of the primary factors that influence the variation of livestock emissions. This study evaluated the relationship between animal activity and three major emissions, PM₁₀, PM_2.5, and ammonia gas, in weaning, growing, and fattening pig houses through continuous monitoring of the animal activity. The movement score of animals was quantified by the developed image analysis algorithm using 10-second video clips taken in the pig houses. The calculated movement scores were validated by comparison with six activity levels graded by an expert group. A comparison between PMs measurement and the movement scores demonstrated that an increase of the PMs concentrations was obviously followed by increased movement scores, for example, when feeding started. The PM₁₀ concentrations were more affected by the animal activity compared to the PM_2.5 concentrations, which were related to the inflow of external PM_2.5 due to ventilation. The PM₁₀ concentrations in the fattening house were 1.3 times higher than those in the weaning house because of the size of pigs while weaning pigs were more active and moved frequently compared to fattening pigs showing 2.45 times higher movement scores. The results also indicated that indoor ammonia concentration was not significantly influenced by animal activity. This study is significant in the sense that it could provide realistic emission factors of pig farms considering animal's daily activity levels if further monitoring is carried out continuously.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.2
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• pp.92-103
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• 1989

This study was performed in order to produce the basic data for devising irrigation project and desalinization countermeasure through analyzing salt movement and desalinzation effects. The Desalinization experiments with water management practices were carried out, using the soil samples collected in New Manguem tideland. The changes of electrical conductivity, exchangeable sodium percentage, pH and hydraulic conductivity during the desalinization experiments, and the correlations between various factors influencing desalinization, were analyzed by the statistical method. The results obtained from this study were summarized as follows: 1. The sample soils used in this study were salin-sotlic soils with the high electrical conductivity and the high exchangeable sodium percentage, and the soil texture was silt loam. 2. A large amount of the soluble salts was removed in the begining of desalinization experiments. The initial electrical conductivity and the initial exchangeable sodium percentage decreased considerably in the beginning, and were gradually slow in the rate of decrease 3. The value of pH showed a tendency to increase during the desalinization and were little by little slow in the rate of increase, and could be estimated by the regression equation. 4. The initial hydraulic conductivity were raised greatly with gypsum treatment and the penmeability was maintained adequately, The hydraulic conductivity and the leaching time elapsed during the desalinization could be estimated by the regression equation. 5. The water requirement for desalinization with various water management practices could be estimated for a given electrical conductivity, exchangeable sodium percentage, and pH reading respectively.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.79-82
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• 2008

Anaerobic biodegradability(AB), which can be determined with the ultimate methane yield by the decomposition of organic materials, is one of the important parameters for the design and the operation of anaerobic digestion plant. In this study, Biochemical Methane Potential(BMP) test has been carried out to evaluate the methane yield of animal manures, such as pig and cattle slurries, and different forage crops cultivated at the reclaimed tideland, such as maize, sorghum, barley, rye, Italian ryegrass(IRG), rape, rush and sludge produced from slaughterhouse wastewater treatment plant(SWTP). In the ultimate methane yield of animal manure, that of pig slurry(no used a EM) was 407 $mlCH_4/gVS_{fed}$ higher than 242 $mlCH_4/gVS_{fed}$ of cattle slurry. The ultimate methane yield of spike-crop rye was 442.36 $mlCH_4/gVS_{fed}$ the highest among different forage crops, the other showed the value above a methane yield of 300 $mlCH_4/gVS_{fed}$. The forage crop could be used as a good substrate to improve the methane production in anaerobic co-digestion together with animal manure.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.3
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• pp.9-16
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• 2003

In support of remote sensing applications for monitoring processes of the Earth system, research was conducted to analyze the basic spectral response related to background soil and vegetation cover characteristics in the visible and reflective infrared wavelengths. Surface samples of seven stations were examined. Five soils were from land-field and two soils from tideland areas. The vegetation cover experiment was conducted on seven soil samples with known natural moisture content (%) by weight. To study the effect of vegetation cover, spectral measurements were taken on five or six vegetation cover treatments of the seven soils with 3 replications in air dry conditions. For collecting RS base data, used spectro-radiometer that measures reflection characteristics between 300~1,100nm was used and measured the reflection of vegetation from bean leaves. The relationships were evaluated for both a general soil line and for the individual lines of five soils, under air-dried condition as well as different vegetation cover ratio, through the determination of the line parameters. As vegetation cover ratio in bean leaves increases, features of soil reflectance decrease and those of plant reflectance become more and more apparent. In proportion to vegetation cover rate, near-infrared reflectance increased and visible reflectance decreased. Analysis results are compared to commonly used vegetation indices(RVI and NDVI ).

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.6
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• pp.33-42
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• 2020

Emission factors for ammonia and particulate matters (PMs) from livestock buildings are of increasing importance in view of the environmental protection. While the existing emission factors were determined based on the emission inventory of other countries, in situ measurement of emission factors is required to construct an accurate emission inventory for Korea. This study is to report measurements of ammonia and PMs emissions from mechanically-ventilated pig houses, which are common types of pig barns in Korea. Ventilation rates and concentrations of ammonia and PMs were measured at the ventilation outlets of a weaner unit, a growing pig unit and a fattening pig unit to calculated the emission factors. The PMs emission was characterized with different aerodynamic diameters (PM_2.5, PM₁₀, and total suspended particulates (TSP)). The measured ammonia emission factors for weaners, growing pigs and fattening pigs were 0.225, 0.869 and 1.679 kg animal^-1 yr^-1, respectively, showing linear increase with pigs' age. The PMs emission factors for three growing stages were 0.023, 0.237 and 0.241 kg animal^-1 yr^-1, respectively for TSP, 0.017, 0.072 and 0.223 kg animal^-1 yr^-1, respectively for PM₁₀, and 0.011, 0.016 and 0.151 kg animal^-1 yr^-1, respectively for PM_2.5. PMs emissions were increased with pigs' age due to increasing feed supply and animal movement. The measured emission factors were smaller than those of the existing emission inventory indicating that the existing ones overestimate the emissions from pig buildings and also suggesting that long-term in situ monitoring at various livestock buildings is required to construct the accurate emission inventory.

• KCID journal
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• v.10 no.1
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• pp.62-72
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• 2003

Tideland reclamation has been known to begin in 13th century in the eastern coast of Ganghwa Island during the Mongolian Invasion in Korea. Traditionally, the tidal reclamation projects have been developed in the coastal with nearly flat inter-tidal zone

• Journal of Korean Society of Rural Planning
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• v.26 no.4
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• pp.81-91
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• 2020

This study was conducted to analyse climate change impact on agriculture infrastructure and propose improved measures on vulnerable areas. Recently, Climate change has resulted in damaging effects on agricultural fields through increases in drought intensity and flood risk. It is expected that this impact will increase over time. This study shows that Gyeong-gi and Chung-nam provinces are affected by drought and Gyeong-buk and Gyeong-nam provinces are affected by heavy rain. However, there are also regional variations within each province. Agricultural infrastructure affected by drought may also be affected by heavy rain. Increased damages on the infrastructure due to increased extreme weather events require preventive measures especially in vulnerable areas. In order to minimize the damage by climate change, we need to introduce a reform in the system which selects project region by analysing climate change impacts. Furthermore, impact assessment of climate change from projects such as 'water supply diversification', 'flooded farmland improvement', and 'irrigation facility reinforcement' also need to be adopted to improve the measures. The results of this study are expected to provide a foundation for establishing measures on coping with climate change in the agricultural sector.

• Journal of Korea Soil Environment Society
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• v.5 no.3
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• pp.25-33
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• 2001

The study was performed to examine the influence of sea tide on a tideland composition by Saemankeum reclamation and to evaluate a correlation between the characteristics of physical and the pollution level of heavy metals. Also, it was investigated the characteristics of heavy metal adsorption through a batch experiment and applied to adsorption isotherm equations. In the results, the flow of sea tide occurred to accumulation action and had an effect on the content of heavy metals. It suggests that influence factors for the content of heavy metals in the tidal flat be grain size, cation exchange capacity and organic matter content. Adsorption capacity of heavy metals occurs to 90% adsorption rate for injection concentration within 30 minutes. The flow patterns in Saemankeum area will undergo a change for soil size distribution. In result, this soil size changed will effect the adsorption capacity of heavy metals.