• Structural Engineering and Mechanics
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• v.23 no.3
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• pp.249-262
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• 2006

In this paper, a simplified mathematical procedure is presented to incorporate nonlinearity in soil material to predict the deceleration time history, penetration depth and other relevant parameters for normal impact of missiles into soil targets. Numerical method is employed for these predictions. The results of the study are compared with experimental observations and predictions available in the literature. A good agreement is found with experimental observations and an improvement is observed with existing predictions. A comparison is also made with linear soil model. Some parametric studies are also carried out to obtain the results of practical interest.

• Journal of Soil and Groundwater Environment
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• v.28 no.6
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• pp.33-44
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• 2023

A risk assessment on the heavy metals including arsenic (As), cupper (Cu), lead (Pb), and zinc (Zn) was investigated by setting exposure routes in agricultural fields. Moreover, the factors requiring improvement in risk assessment were also discussed through a review of the dermal absorption slope factor (SF_abs) and total amount of suspended particles (TSP) in the current risk assessment guidelines. Assessment results show that the total cancer risk (TCR) of As through crop and soil ingestion was 1.51E-03 in adults and 6.37E-4 in children, which indicated a carcinogenic risk (exceeding 1E-05). On the other side, the harzard index (HI) was 3.37 in adults and 1.41 in children, which was evaluated as having a non-carcinogenic risk (>1). The carcinogenic purification targets for As were calculated to be 6.84 mg/kg in adults and 6.86 mg/kg in children, while the non-carcinogenic purification targets were calculated to be 13.43 mg/kg for adults and 22.54 mg/kg for children. When applying SF_abs 61 of the current guidelines, it appears that there is a carcinogenic risk even though the As exposure concentration is below the area of concern 1 standard (25 mg/kg), which suggestes that additional research on this factor is required for the risk assessment. In order to apply the measured suspended particle concentration to risk assessment, TSP should be derived from PM10 using an appropriate correlation equation. As a result, it is suggested to improve the risk assessment guidelines so that the mesured PM10 value measured in the field can be used directly.

• Journal of Environmental Impact Assessment
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• v.25 no.1
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• pp.41-50
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• 2016

Environmental impact assessment has been implemented for more than 30 years in Korea. During that period, various amendments were carried out about target plan and assessment factors. However, in current environmental impact assessment act, only a few factors has been considered for soil environment assessment. This study analyzes the national and foreign environmental impact assessment guidelines on soil related factors and figures out the problems and implications of Korean environmental impact assessment. In Korea, water quality, topography and geology, hydraulics and hydrology, and soil contamination were analyzed as a soil related factors. The main assessment targets were pollution related factors such as soil pollution levels, amount of rainfall runoff, and non-point sources. However, in the case of foreign guidelines, soil compaction, soil sealing, and soil salinization is being analyzed for evaluating function and quality of soil environment. The revision of soil-related factors are needed for sustainable development of Korea.

• Hwankyungkyoyuk
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• v.11 no.2
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• pp.69-82
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• 1998

This study was performed to investigate the trends in Environmental Education Research of Korea. In this study, the papers in $\ulcorner$Hwankyungkyoyuk$\lrcorner$ (Journal of the Korean Society for Environmental Education) and $\ulcorner$Journal of the Korean Association for Research in Science Education$\lrcorner$ from the initial number to the latest number were investigated. The category of analysis in this study were the number of papers, research area, method, character, the major targets of Environmental Education, the major targets of research, the purpose of Environmental Education, and the contents of environment. The results of this study are as follows: 1. The number of papers in $\ulcorner$Hwankyungkyoyuk$\lrcorner$ were 178 and in $\ulcorner$Journal of the Korean Association for Research in Science Education$\lrcorner$ were 406(10 of them were related in environmental education) 2. The research areas of the papers were Environmental Education(52.4%), Social Environmental Education(19%), Environmental Science(8.5%), Science Education(7.9%), and Social Education(3.2%). 3. The major parts of the method of the papers were literature review(31.7%), survey research(21.2%), and descriptive study(20.3%). 4. More than half of the character of the papers were research on the actual condition(35.4%) and consciousness (17.9%), 5. The major targets of Environmental Education of the papers were secondary school students(33.9%) and elementary school students(18.8%). 6. The major targets of researches of the papers were secondary school students(33.8%), teachers(30.0％), the general public(20.0％), and elementary school students(18.8%). 7. The purpose of Environmental Education of the papers were Values and Attitudes(31.2%), Behaviors and Participations(29.6%), Knowledges and Informations(27.2%), and Skills(12%). 8. The contents of Environment of the papers were waste(27.7%), water quality(15.2%), the whole environment(12.5%), air quality(9.8%), natural environment(5.4%), soil(4.4%), energy(4.4%), and so on. The results indicated that the Environmental Education research of Korea were needed to be reinforced in the field of qualitative research method, teaching and learning strategy, the development of learninyg meterals, and teacher education.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.3
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• pp.251-256
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• 2015

The study was conducted to determine greenhouse gas (GHG) inventories in grasslands. After 'Low Carbon Green Growth' was declared a national vision on 2008, Medium-term greenhouse gas reduction was anticipated for 30% reduction compared to Business As Usual (BAU) by 2020. To achieve the reduction targets and prepare to enforce emissions trading (2015), national GHG inventories were measured based on the 1996 Intergovernmental Panel on Climate Change Guidelines (IPCC GL). The national Inventory Report (NIR) of Korea is published every year. Grassland sector measurement was officially added in 2014. GHG removal of grassland soil was measured from 1990 to 2012. Grassland area data of Korea was used for farmland area data in the "Cadastral Statistical Annual Report (1976~2012)". Annual grassland area corresponding to the soil classification was used "Soil classification and commentary in Korea (2011)". Grassland area was divided into 'Grassland remaining Grassland' and 'Land converted to Grassland'. The accumulated variation coefficient was assumed to be the same without time series changes in grassland remaining grassland. Therefore, GHG removal of soil carbon was calculated as zero (0) in grassland remaining grassland. Since the grassland area increases constantly, the grassland soil sinks constantly . However, the land converted to grassland area continued to decrease and GHG removal of soil carbon was reduced. In 2012 (127.35Gg $CO_2$), this removal decreased by 76% compared to 1990 (535.71 Gg $CO_2$). GHG sinks are only grasslands and woodlands. The GHG removaled in grasslands was very small, accounting for 0.2% of the total. However, the study provides value by identifying grasslands as GHG sinks along with forests.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.6
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• pp.110-117
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• 2011

Seashore landfill projects use undersea pump dredging method for construction of airport and factory site. Coarse grain soil from the dredging is considered for use at inland. West sea shore bottom consists of primarily coarser grained silt-sand and this component contains far more percentage than is the case with East sea and South sea area. This soil shows very different characteristic at consolidation and compaction behavior. This research targets to utilize this type of dredging soil. Test specimen is from West sea (Saemangum) dredged soil landfill site. Model analysis is done for getting prediction of original soil relative density and N-value from dynamic compaction energy variance. Dynamic compaction energy is calculated for efficient foundation design.

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.521-529
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• 2016

Extensive use of antibiotics over recent decades has led to bacterial resistance against antibiotics, including gentamicin, one of the most effective aminoglycosides. The emergence of resistance is problematic for hospitals, since gentamicin is an important broad-spectrum antibiotic for the control of bacterial pathogens in the clinic. Previous study to identify gentamicin resistance genes from environmental samples have been conducted using culture-dependent screening methods. To overcome these limitations, we employed a metagenome-based culture-independent protocol to identify gentamicin resistance genes. Through functional screening of metagenome libraries derived from soil samples, a fosmid clone was selected as it conferred strong gentamicin resistance. To identify a specific functioning gene conferring gentamicin resistance from a selected fosmid clone (35-40 kb), a shot-gun library was constructed and four shot-gun clones (2-3 kb) were selected. Further characterization of these clones revealed that they contained sequences similar to that of the RNA ligase, T4 rnlA that is known as a toxin gene. The overexpression of the rnlA-like gene in Escherichia coli increased gentamicin resistance, indicating that this toxin gene modulates this trait. The results of our metagenome library analysis suggest that the rnlA-like gene may represent a new class of gentamicin resistance genes in pathogenic bacteria. In addition, we demonstrate that the soil metagenome can provide an important resource for the identification of antibiotic resistance genes, which are valuable molecular targets in efforts to overcome antibiotic resistance.

• Plant Breeding and Biotechnology
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• v.6 no.4
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• pp.454-462
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• 2018

Yield and grade are the key factors that affect production value of peanut. The objective of this study was to identify QTLs for pod yield, hundred-seed weight, and total sound mature kernel (TSMK). A total of 90 recombinant inbred lines, derived from Tamrun OL07 and a breeding line Tx964117, were used as a mapping population and planted in Brownfield and Stephenville, Texas. A genetic map was developed using 1,211 SNP markers based on double digest restriction-site associated DNA sequencing (ddRAD-seq). A total of 10 QTLs were identified above the permutation threshold, three for yield, three for hundred-seed weight and four for TSMK, with LOD score values of 3.7 - 6.9 and phenotypic variance explained of 12.2% - 35.9%. Among those, there were several QTLs that were detected in more than one field experiment. The commonly detected QTLs in this study may be used as potential targets for future breeding program to incorporate yield and grade related traits through molecular breeding.

• Journal of Soil and Groundwater Environment
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• v.10 no.5
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• pp.1-10
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• 2005

Policies of the United States, the United Kingdom, the Netherlands, Germany and Denmark were compared and analyzed on risk assessment of contaminated sites. These countries were chosen from a feasible preliminary analysis of 18 countries of the European Union and the U. S. All the countries selected met two major criteria : I) implementation of risk assessment to determine the soil contamination and remediation targets of contaminated sites, ii) use of soil guidance values and risk assessment as complementary measures to determine soil contamination. Suggested policy improvements to Korea regarding these issues include i) legislation of a rational risk assessment methodology of contaminated sites, and ii) enactment of collaboration of risk assessment with the soil guidance values. To establish effective risk assessment legislation, additional in-depth research on social, economic and long-term effects of the proposed risk assessment methodologies, as well as the mutual consent of all parties including academia, industry, and administration will be necessary. Linking risk assessment with soil guidance values would be applicable to a site contaminated where the contaminant concentration exceeds a certain soil guidance value. In parallel, application of risk assessment to a site where a contaminant concentration is naturally different such as mining sites would be plausible. The policy suggestions above are not yet conclusive due to a lack of policy implementation, and simulation. Thus, additional research on developing risk assessment methodology is needed. Nevertheless, initiation of the suggested policy would increase the efficacy of Korean policy regarding the survey and remediation of contaminated sites.

• Korean Journal of Remote Sensing
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• v.38 no.5_1
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• pp.571-585
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• 2022

As the threat of natural disasters such as droughts, floods, forest fires, and landslides increases due to climate change, social demand for high-resolution soil moisture retrieval, such as Synthetic Aperture Radar (SAR), is also increasing. However, the domestic environment has a high proportion of mountainous topography, making it challenging to retrieve soil moisture from SAR data. This study evaluated the usability of Sentinel-1 SAR, which is applied with the Artificial Neural Network (ANN) technique, to retrieve soil moisture. It was confirmed that the backscattering coefficient obtained from Sentinel-1 significantly correlated with soil moisture behavior, and the possibility of stand-alone use to correct vegetation effects without using auxiliary data observed from other satellites or observatories. However, there was a large difference in the characteristics of each site and topographic group. In particular, when the model learned on the mountain and at flat land cross-applied, the soil moisture could not be properly simulated. In addition, when the number of learning points was increased to solve this problem, the soil moisture retrieval model was smoothed. As a result, the overall correlation coefficient of all sites improved, but errors at individual sites gradually increased. Therefore, systematic research must be conducted in order to widely apply high-resolution SAR soil moisture data. It is expected that it can be effectively used in various fields if the scope of learning sites and application targets are specifically limited.