• Explosives and Blasting
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• v.18 no.2
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• pp.7-13
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• 2000

Abstract The characteristics of bed rock in the study area was classified by means of the crack coefficient estimated from the seismic velocities of in-situ and intact rocks. Various statistical methods were investigated in order to minimize the possible errors in estimating the predictive equation of blasting vibration and to enhance the determination coefficient $R^2$, for more reliable estimation. The determination coefficient showed the highest in the analysis for those groups using weighting function with the number of samples. The analysis for the weighting function employed with standard coefficient and variance also enhanced the determination coefficients significantly compared to the others, but the reliability was slightly lower than results obtained former method. Therefore the most reliable predictive equation of blasting vibration was found to be obtained from a regression analysis of the mean vibration level using the weighting of same distance groups within 15m with the same explosive charge weight per delay. The coefficients, K and n 317.4 and -1.66, respectively, when using the square root scaling, and 209.9 and -1.66, respectively, when using the cube root scaling. The analysis also showed that the square root scaling may be used in the distance less than 31m form the blast source, and the cube root scaling in the distance more than 31m for safe design.

• Journal of Life Science
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• v.30 no.7
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• pp.625-629
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• 2020

The Ocean is a rich source of diverse living organisms include viruses. In this study, we examined the microbial communities in the sea adjacent to Jeju Island in two seasons by metatranscriptomics. We collected and extracted total RNA, and, using the next-generation sequencing HiSeq 2000 and de novo transcriptome assembly, we identified 652,984 and 163,759 transcripts from the March and December samples, respectively. The most abundant organisms in March were bacteria, while eukaryotes were dominant in the December sample. The bacterial communities differed between the two samples, suggesting seasonal change. To identify the viruses, we searched the transcripts against a viral reference database using MegaBLAST with the most identified being bacteriophages infecting the marine bacteria. However, we also revealed an abundance of transcripts associated with diverse herpesviruses in the two transcriptomes, indicating the presence or possible threat of infection of fish in the sea around Jeju Island. This data is valuable for the study of marine microbial communities and for identifying possible viral pathogens.

• Journal of the Korean GEO-environmental Society
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• v.21 no.5
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• pp.23-33
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• 2020

As the scale of the economy expands, the number of cases of damage in enclosed spaces such as tunnels is increasing due to the accident of transportation vehicles of dangerous substances such as explosive flammable materials that have increased rapidly. In the case of road tunnels in particular, in the aspect of protection against the long-winding trend and the environment in the downtown area, the number of cases of passing through the downtown area increases, and securing the safety of structures against unexpected extreme disasters such as explosions during tunnel passage is very urgent. For this reason, developed countries are already conducting a review of internal bombardment, but there are almost no evaluation and countermeasures for explosion risk in Korea. Therefore, in this study, in order to evaluate the explosion safety of road tunnels, a boiling liquid explosive explosion (BLEVE), which is considered to have the greatest explosion load among vehicles driving on the road, is set as a reference explosion source, and the equivalent TNT explosion load is used for simulation of the explosion. A method of conversion was presented. In addition, by applying the derived explosion load, dynamic behavior simulation was performed by assuming various variables for the tunnel, and the explosion safety of the tunnel was analyzed.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.4
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• pp.319-324
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• 1985

This study was designed to evaluate the feasibility of direct application of quenched slag, as a silicate fertilizer byproduct of iron and steel industry. A field experiment was conducted on a low silica content paddy soil and its effect was compared to over corresponding air-cooled slag of milled commercial silicate fertilizer on rice plant growth and yields. The yields of rice were slightly higher in the commercial air-cooled slag than in the quenched slag, however, there was no significant statistical difference. The silica content of rice plants at harvest was higher in commercial silicate fertilizer than that of quenched slag. The available soil silica was high in quenched slag at the early growing stage, however, at harvest higher in air-cooled slag, which meant that the quenched slag might release silica quickly in soil. This results indicated that the slag could be considered resource as a silicate fertilizer.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.447-451
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• 2008

'Goamibyeo', a mid-late maturing ecotype with high amylose content in kernels, was developed by the rice breeding team of National Yeongnam Agricultural Experiment Station(NYAES) in 2000 and released in 2001. This variety was derived from the three way cross of Milyang 95//Kimcheonaengmi/$2^*Ilpumbyeo$ (in 1992 summer) through the pedigree breeding method and designated as 'Milyang 168' in 1997. The heading date of 'Goamibyeo' was Aug. 18 in ordinary season with culm length of 85 cm. However, 'Goamibyeo' showed susceptible to bacterial leaf blight, stripe virus and leaf blast disease. The amylose content of 'Goamibyeo' in milled rice kernels is about 26.7% with translucent and clear in chalkness. Thus, 'Goamibyeo' is expected to be used as a source grain for rice noodle industries. The milled rice yield potential of 'Goamibyeo' is about 5.38 MT/ha in local adaptability test of three years and it would be adaptable to Yeongnam plain of Korea.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.1
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• pp.47-60
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• 2021

Hydrogen is a next-generation energy source, and according to the roadmap for activating the hydrogen economy, it is expected that industries to stably produce, store, and transport of hydrogen as well as the supply of hydrogen fuel cell vehicles will be made rapidly. Accordingly, safety measures for accidents of hydrogen vehicles in confined spaces such as tunnels are required. In this study, as part of a study to ensure the safety of hydrogen fuel cell vehicles in road tunnels, a basic investigation and research on the risk of fire and explosion due to gas leakage and hydrogen tank rupture among various hazards caused by hydrogen fuel cell vehicle accidents in tunnels was conducted. The following results were obtained. In the event of hydrogen fuel cell vehicle accidents, the gas release rate depends on the orifice diameter of TPRD, and when the gas is ignited, the maximum heat release rate reaches 3.22~51.36 MW (orifice diameter: 1~4 mm) depending on the orifice diameter but the duration times are short. Therefore, it was analyzed that there was little increase in risk due to fire. As the overpressure of the gas explosion was calculated by the equivalent TNT method, in the case of yield of VCE of 0.2 is applied, the safety threshold distance is analyzed to be about 35 m, and number of the equivalent fatalities are conservatively predicted to reach tens of people.

• Explosives and Blasting
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• v.40 no.3
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• pp.19-32
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• 2022

Hydrogen is a fuel having the highest energy compared with other common fuels. This means hydrogen is a clean energy source for the future. However, using hydrogen as a fuel has implication regarding carrier and storage issues, as hydrogen is highly inflammable and unstable gas susceptible to explosion. Explosions resulting from hydrogen-air mixtures have already been encountered and well documented in research experiments. However, there are still large gaps in this research field as the use of numerical tools and field experiments are required to fully understand the safety measures necessary to prevent hydrogen explosions. The purpose of this present study is to develop and simulate 3D numerical modelling of an existing hydrogen gas station in Jeonju by using handheld LiDAR and Ansys AUTODYN, as well as the processing of point cloud scans and use of cloud dataset to develop FEM 3D meshed model for the numerical simulation to predict peak-over pressures. The results show that the Lidar scanning technique combined with the ANSYS AUTODYN can help to determine the safety distance and as well as construct, simulate and predict the peak over-pressures for hydrogen refueling station explosions.

• The Plant Pathology Journal
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• v.39 no.4
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• pp.361-373
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• 2023

In plant-pathogen interactions, Magnaporthe oryzae causes blast disease on more than 50 species of 14 monocot plants, including important crops such as rice, millet, and most 15 recently wheat. M. oryzae is a model fungus for studying plant-microbe interaction, and the main source for fungal pathogenesis in the field. Here we report that MoJMJD6 is required for conidium germination and appressorium formation in M. oryzae. We obtained MoJMJD6 mutants (ΔMojmjd6) using a target gene replacement strategy. The MoJMD6 deletion mutants were delayed for conidium germination, glycogen, and lipid droplets utilization and consequently had decreased virulence. In the ΔMojmjd6 null mutants, global histone methyltransferase modifications (H3K4me3, H3K9me3, H3K27me3, and H3K36me2/3) of the genome were unaffected. Taken together, our results indicated that MoJMJD6 function as a nuclear protein which plays an important role in conidium germination and appressorium formation in the M. oryzae. Our work provides insights into MoJMJD6-mediated regulation in the early stage of pathogenesis in plant fungi.

• Food Science and Preservation
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• v.15 no.3
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• pp.483-490
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• 2008

Several tartaric acid-degrading bacteria were isolated from Korean grape wine pomace after enrichment culture at $30^{\circ}C$ for 10 days in liquid media containing tartaric acid Among them, strains KMBL 5777 and KMBL 5778 exhibited the highest level in the growth and tartaric acid degradability in a medium containing 0.2%(w/v) tartaric acid as a sole carbon source. They were identified as Acetobacter tropicalis based on their morphological and physiological characteristics as well as their 16S rDNA sequences. Blast search of the 16S rDNA sequences revealed that the isolated strains are closest to Acetobacter tropicalis. Homologies of the sequences of KMBL 5777 and KMBL 5778 were 96.0 and 98.9%, respectively with those of A. tropicalis LMG 1663. Both the two bacteria showed higher tartaric acid degradation at $25^{\circ}C$ that those at 20 and $30^{\circ}C$. They could degrade tartaric acid at a wide range of pH between 4.0 and 7.0 with the most rapid degradability at pH 7.0. However, when the bacteria were grown for 8 days, the same level of tartaric acid degradation was observed at pH 4.0, 5.0, 6.0 and 7.0, which was 90.0% of degradation of the acid.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.262-266
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• 2010

'Josaengheugchal', a new blackish purple pigmented glutinous japonica rice cultivar, was developed by the rice breeding team of Department of Functional Crop, NICS, RDA in 2004. This cultivar was derived from a cross between 'Tohoku 149' as black glutinous source and 'Sx 864' as purple colored rice in 1992 and 1993 winter season, and selected by pedigree breeding method until $F_6$ generation. As a result, a promising line, YR15907-6-8-1-5, was advanced and designated as the name of 'Milyang 194' in 2001. The local adaptability test of 'Milyang 194' was carried out at seven locations from 2002 to 2004 and it was named as 'Josaengheugchal'. 'Josaengheugchal' is an early maturing cultivar and has 71 cm culm height. It has higher anthocyanian content compared with 'Heugnambyeo'. It is moderately resistant to leaf blast but susceptible to other disease and insect pests. The yield potential of 'Josaengheugchal' in brown rice was about 4.21 MT/ha at ordinary fertilizer level in local adaptability test. This cultivar would be adaptable to the plain paddy field of middle, Honam, and Yeomgnam in Korea under ordinary and double cropping system.