• Proceedings of the Korean Society of Crop Science Conference
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• 2018.10a
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• pp.172-172
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• 2018

• Structural Engineering and Mechanics
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• v.89 no.5
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• pp.525-538
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• 2024

An explosion from a specific source can generate high pressure, causing damage to structures and people in and around them. For the design of protective structures, although explosion overpressure is considered the main loading parameter, parts are only considered using standard design procedures, excluding special installations. Properties of the explosive, such as molecular structure, shape, dimensional properties, and the physical state of the charge, determine the results in a high-grade or low-grade explosion. In this context, it is very important to determine the explosion behaviors of the structures and to take precautions against these behaviors. Especially structures in areas with high explosion risk should be prepared for blast loads. In this study, the behavior of non-anchored blast resistant modular buildings was investigated. In the study, analyzes were carried out for cases where modular buildings were first positioned on a reinforced concrete surface and then directly on the ground. For these two cases, the behavior of the modular structure placed on the reinforced concrete floor against burst loads was evaluated with Stribeck curves. The behavior of the modular building placed directly on the ground is examined with the Pais and Kausel equations, which consider the structure-ground interaction. In the study, head and neck injuries were examined by placing test dummies to examine human injury behavior in modular buildings exposed to blast loads. Obtained results were compared with field tests. In both cases, results close to field tests were obtained. Thus, it was concluded that Stribeck curves and Pais Kausel equations can reflect the behavior of modular buildings subjected to blast loads. It was also seen at the end of the study that the human injury criteria were met. The results of the study are explained with their justifications.

• Korean Journal Plant Pathology
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• v.13 no.2
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• pp.79-84
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• 1997

Incidence of rice blast on new rice cultivars and elite lines was observed from 194 to 1996 in Icheon, Chuncheon, Jecheon and Naju areas. The observations were made in the nuseries and in the fields. In the nurseries, only cultivars Daesanbyeo and Hyangmibyeo 2 showed moderate levels of resistance to leaf blast, with the disease index 0 to 6. From the field observations, it was found that cultivars Hyangmibyeo 2 and Suwon 414 were highly resistant to leaf blast, but susceptible to neck blast. the fields, leaf blast was not observed. In general, there was great yearly and regional variation in the incidence of neck blast within the same cultivars, some times ranging from 0 to 100% of incidence. However, the range of fluctuation in the disease incidence were relatively small in the cultivars Daejinbyeo (0∼17.5%), Daesanbyeo (0∼4.0%), Donganbyeo (0∼21.4%) and Hwasambyeo (0∼13.9%). Hyangmibyeo 2 and Seojinbyeo were rarely infected with neck blast in Chuncheon and Naju all of the years, the same cultivars were severely infested with neck blast; 45.1 and 45.5%, respectively, in Jecheon in 1995. The occurrence of different races of rice blast fungus were different at different areas. However, it was found that in Icheon, Chuncheon, Jecheon and Naju areas, the dominant races were KI-409, KJ-201 and KJ-301.

• Journal of the Korean Institute of Gas
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• v.26 no.1
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• pp.27-33
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• 2022

As the scale of explosions diversifies along with the expansion of gas handling and storage facilities, studies on explosion-proof facilities in preparation for accidents is being actively conducted. The gastight door blocks the expansion pressure caused by blast waves or internal fires, and at the same time protects the personnel and equipment inside. For gastight doors, the regulations related to explosion-proof design are not clearly presented, and studies on the explosion pressure resistance performance evaluation of the facility are insufficient. In this study, the gastight door was modeled in a 3D shape with reference to the regulation ASTM regarding the gastight door standard. Afterwards, evaluation for blast-resistant performance of gastight door using Numerical simulation was evaluated by using ANSYS Explicit Dynamics to compare the deformation.

• Korean journal of applied entomology
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• v.11 no.1
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• pp.41-43
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• 1972

1. In order to investigate the epidemic outbreak of rice blast disease on the resistant variety Kwankon in 1969, this investigation was undertaken as a basis for breeding resistant varieties. 2. The 16 isolates collected from Kyunggi area were inoculated at the 3-4 leaf stage on 12 Japanese differential varieties used for identifying races under greenhouse conditions. Out of 16 isolates 15 were identified as C race group and one as N race group. Of the 15 rates, nine were C-8, two were C-7 and two were C-1. Of the remaining two isolates, one was similar to C-1, and the other was similar to C-5. 3. It is concluded that the epidemic in the resistant variety 'Kwanok' was due to the occurrence of the C race group, which can infect the Chinese type varieties.

• Korean Journal Plant Pathology
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• v.3 no.1
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• pp.3-7
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• 1987

Ethanol-soluble amino acids and phenolics in healthy and blast-infected leaves of the susceptible rice cultivar Nakdong and adult-plant-resistant cultivar Dobong were quantitatively analyzed, At the 3 days after inoculation, the levels of soluble amino acids and phenolics in the infected fifth and eighth leaves of the two cultivars ere similar to those of comparable healthy controls. As blast lesions appeared on the leaves at the 5 days after inoculation, the soluble amino acids and phenolics began to increase. At the 7 days after inoculation, the levels of amino acids and phenolics were about 1.5-3 times more than those in healthy controls at the five-and eight leaf stages. The adult-plant-resistant cultivar Dobong showed higher amounts of soluble amino acids and phenolics in both healthy and infected fifth and eighth leaves than did the susceptible cultivar Nakdong, although Dobong was less infected by Pyricularia oryzae than Nakdong, The pronounced increases in amino acids and phenolics in rice leaves of the cultivar Dobong during the blast infection may play an important role in the expression of adult-plant resistance to blast.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.67.2-68
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• 2003

A rice cultivar, Taebaegbyeo, is highly resistant to rice blast and moderately resistant to bacterial leaf blight (BLB) caused by Magnaporthe grisea and Xanthomonas oryzae pv. oryzae, respectively. To study the rice disease resistance mechanism, we generated rice deletion M3 mutants by gamma-ray irradiation. Blast and BLB responses of 16,000 M3 mutants were screened by inoculating mixtures of 4 races (KJ-201, H-1113a, KI-313, KI-409) of M. grisea and 3 Korean races of X. oryzae pv. oryzae. We selected so far 21 M3 mutants of Taebaegbyeo showing high susceptibility to the diseases. One of the mutants, KCT-6417, was susceptible to KI-1113a race of M. grisea, suggesting the deletion of a race-specific blast resistance gene in the mutant. To isolate rice genes involved in blast resistance and defense response, we take a PCR-based suppression subtractive hybridization approach using cDNAs of blast-inoculated wild type and the KCT-6417 as a tester and a driver, respectively. Genes specifically expressed in the wild type will be presented. The selected genes would give us a clue to understand mechanism for the race specific resistance and defense responses against M. grisea H-1113a in Taebaegbyeo.

• Journal of Korean Association for Spatial Structures
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• v.11 no.4
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• pp.11-15
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• 2011

• Steel and Composite Structures
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• v.30 no.3
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• pp.217-230
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• 2019

One of the most important design criteria in underground structure is to design lightweight protective layers to resist significant blast loads. Sandwich blast resistant panels are commonly used to protect underground structures. The front face of the sandwich panel is designed to resist the blast load and the core is designed to mitigate the blast energy from reaching the back panel. The design is to allow the sandwich panel to be repaired efficiently. Hence, the underground structure can be used under repeated blast loads. In this study, a novel sandwich panel, named RC panel - Helical springs- RC panel (RHR) sandwich panel, which consists of normal strength reinforced concrete (RC) panels at the front and the back and steel compression helical springs in the middle, is proposed. In this study, a detailed 3D nonlinear numerical analysis is proposed using the nonlinear finite element software, AUTODYN. The accuracy of the blast load and RHR Sandwich panel modelling are validated using available experimental results. The results show that the proposed finite element model can be used efficiently and effectively to simulate the nonlinear dynamic behaviour of the newly proposed RHR sandwich panels under different ranges of free air blast loads. Detailed parameter study is then conducted using the validated finite element model. The results show that the newly proposed RHR sandwich panel can be used as a reliable and effective lightweight protective layer for underground structures.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.137-145
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• 1981

Using the milled, blast infected leaves (BIL) as an inoculum source on the screening for the resistance to blast of rice plant was a simple and useful technique. The temperature with high (25^\circ C\sim 35^\circ C) and low (15^\circ C\sim 28^\circ C) and the water stressed or not, was conditioned of to the inoculation with the BIL to the test varieties in seedling stage. In low temperature, most of the varieties were more infected with blast, however the Indica-Japonica hybrids were more infected in high temperature conditions. The water stressed was more infected with blast than the not stressed. The interaction of variety with water stress was not so much as that of variety with temperature. Resistant reaction to blast (BIL) was not affected by the temperature and water stress, but the moderately resistant or susceptible one was much affected by them. Inoculum of BIL was virulent to the newly bred Indica-Japonica hybrid cultivars such as Tongil, Nopung, etc, but not virulent to the Japonica cultivars such as Nongbaek, Jinheung, etc. The discrete, mixed or variable lesions were observed mainly in the moderately resistant or susceptible cultivars such as Kanto 51, Yashiromochi, Ishikari-shiroke, etc.