• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.339-345
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• 2020

Recently, abnormal weather conditions, such as extreme high temperatures and droughts, have increased in frequency due to climate change, there has accordingly been growing concern regarding the detrimental effects on field crop, including soybean. Therefore, this study was conducted to examine the effects of increased temperatures on soybean growth and yield using a temperature gradient chamber (TGC). Two major types of soybean cultivar, a medium- seed cultivar such as Daepung-2 and a large-seed cultivar such as Daechan, were used and four temperature treatments, aT+1℃ (ambient temperature+1℃), aT+2℃ (ambient temperature+2℃), aT+3℃ (ambient temperature+3℃) and aT+4℃ (ambient temperature+4℃) were established to examine the growth response and seed yield of each cultivar. Seed yield showed a higher correlation with seed weight (r=0.713***) and an increase in temperature affected seed yield by reducing the single seed weight. In particular, the seed growth rate of the large-seed cultivar (Daechan) increased at high temperature, resulting in a reduction in the number of days for full maturity. Our results accordingly indicate that large-seed cultivar, such as Daechan, is potentially vulnerable to high temperature stress. The results of this study can be used as basic data in the development of cultivation technology to reduce the damage caused by elevated temperatures. Also, further research is required to evaluate the response of each process contributing to seed yield production under high temperatures.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.237-243
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• 1992

To determine effects of simulated acid rain on the growth and yield of rice, soybean and sesame, and on the soil acidity, two cultivars of rice, soybean and sesame were exposed twice a week to one of four simulated rain acidities[pH 2. 6, 3. 6, 4. 6 and 5. 6(control)]. The plants were protected from ambient rain by a polyethylene film cover. No visible damage due to the simulated acid rain was observed at any stage of growth for either of the crops. In rice, heading date, plant height and yield components except ripening ratio were not significantly affected by the pH ofsimulated rain, but the ripening ratio and rough rice yield linearly decreased as the pH of simulated rain was decreased. In soybean, maturing date and yield components except 100 seed weight were not significantly influenced by the pH of simulated rain, but the 100 seed weight and yield linearly decreased as the pH of simulated rain was decreased. Seed yield and the other agronomic characteristics of sesame were not significantly affected by the pH of simulated rain. Soil pH after cropping rice, soybean and sesame decreased as pH of simulated rain was decreased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.501-505
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• 2003

The growth characteristics and damage of naked barley infected with barley yellow mosaic virus (BaYMV) were investigated between resistant and susceptible varieties in habitual field plot of BaYMV BaYMV of the barley plants with typical disease symptom were identified by enzyme linked immunosorbent assay (ELISA) test. The visual degree (0-9) based on disease symptoms of BaYMV was different as 9 and 1 between susceptible variety Baegdong and resistant variety Naehanssalbori, respectively. Susceptible variety, Baegdong showed significant damage in culm length, number of kernel per spike and tiller per square meter but not in 1,000 kernel weight, so these results caused yield reduction to only 80% comparing to the control. Seed germination did not affected by BaYMV infection both in susceptible and resistant variety. In grain quality test, abortive grain yale and crude protein content were significantly increased compared to the control. The relationships between BaYMV infection and growth characteristics showed the negative correlations in culm length, number of tiller, 1000 kernel weight and yield, but it showed the positive correlation in crude protein contents. These results implied that BaYMV can affect not only barley growth and yield but grain quality.

• The Korean Journal of Mycology
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• v.12 no.2
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• pp.65-73
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• 1984

Strain IV caused highest reduction of germination and caused abnormal elongation of all part of the plant which finally died. Milyang 23 and Nampungbyeo formed mesocotyl. Samnambyeo and Jinjubyeo did not formed mesocotyl on the soil surface in nursery boxes when they were planted on soil infested with each strain of F. moniliforme. Infected seedlings with mesocotyl recovered after transplanting in the the field. The most frequency of Strain IV was isolated from infected rices and this strain was isolated from all part of rice. When rice seedling infected with Strain IV were transplanted in paddy field, most of rice showed Bakanae symptom. Ear emergence of rice was more delayed when seedlings infected with Strain IV were transplanted than that of healthy plant. Number of panicle per hill and grain yield from rice when infected rice seedling by Strain IV were transplanted were more decreased than that of the healthy plant in paddy field.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.3
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• pp.257-265
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• 1996

To obtain the basic informations necessary to develop the production technology of vegetable soybean seeds, this study was conducted at the National Crop Experiment Station, RDA, Suwon, Korea in 1993. Seeds of three vegetable soybean varieties, 'Mikawashima', 'Hwaeomputkong', and 'Seokryangputkong' produced at Pyeongchang, a highland in Korea and introduced from Japan were planted on April 20 in the field. The emergence rate among varieties was significanlty different. Emergence rate of seeds produced at Pyeongchang was higher by 7% than that of the seeds from Japan. Rate of pod infection by Phamapsis spp., brown spot by Septaria glycines, soybean mosaic virus(SMV), and downy mildew by Peronospora manshurica in the field was not different between locations. The growth characteristics, yield components, and green pod and grain yields were not different between locations. Therefore, it was proved that the production of vegetable soybean seeds with the better quality and higher emergence is possible in highland, Korea. possible in highland, Korea.

• ALGAE
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• v.28 no.4
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• pp.371-378
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• 2013

Water and methanolic extracts of Ecklonia cava, a marine brown alga, were prepared by ultrasonic extraction (UE) and conventional extraction (CE) methods. The radical-scavenging activity and the inhibitory effects against hydrogen peroxide ($H_2O_2$)-induced DNA damage of the extracts were investigated. All extracts prepared by CE exhibited higher total polyphenolic content than that in the extracts prepared by UE. Extraction yield and total phenolic content increased as the UE time increased. The radical-scavenging activities increased as the UE time increased. All extracts prepared by CE exhibited higher 1,1-diphenyl-2-pricrylhydrazyl (DPPH) and hydroxyl radical-scavenging activities than did those prepared by UE. Extracts prepared by UE showed stronger scavenging activities on alkyl radical and $H_2O_2$ than those prepared by CE did. Methanolic extract with UE 12 h (100MEU-12h) and methanolic extract with CE 24 h (100MEC-24h) were selected and evaluated by comet assay for their inhibitory effect against $H_2O_2$-induced DNA damage. 100MEU-12h showed slightly greater protective effect against $H_2O_2$-induced DNA damage than 100MEC-24h. Thus, UE can be effectively used as a seaweed extraction technique, and there is potential for scale-up of the extraction process.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.5
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• pp.116-122
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• 2014

In this study, 2 kinds of twist run models as exercise equipments are compared by durability analyses of fatigue and vibration. Maximum equivalent stresses are shown as 3.3 MPa and 16.6 MPa at the parts of stress concentrations at models 1 and 2. As the values becomes much lower than yield stress of this models, these models are shown to be safe designs. Model 1 becomes stronger than model 2 at natural frequency analysis. Fatigue lives become lowest at four axis parts and one axis part respectively in cases of models 1 and 2. Maximum damage probability at fatigue is shown to be 2.4% near the average stress of 0 in case of model 1 but this probability becomes 0.6 % in case of model 2. Model 1 has the maximum damage possibility 4 times more than model 2 at these states. As the result of this study is applied by the design of twist run, the prevention on fatigue damage and the durability are predicted.

• Journal of the Korean Ceramic Society
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• v.35 no.5
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• pp.429-436
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• 1998

The mechanical properties and damage mode of {{{{ {Y}_{2 } {O}_{3} }}-doped tetragonal (Y-TZP) can-didated as biomaterials were performed under indentation stress-strain curve critical load for yield and cracking strength degradation and fatigue behavior with Hertzian indentation tests. This material shows the brittle behavior which is confirmed by indentation stress-strain response. The critical load for cracking(Pc) is much higher than that for yields (Py) indicating crack resistance Strength were strongly dependant on contact area and there were no degradation when the indenter size was ${\gamma}$=3.18 mm suggesting that Y-TZP should be highly damage tolerant to the blunt contacts. Multi-cycle contact were found to be innocuous up to {{{{ {10 }^{6 } }} cycles at 500N and {{{{ {10 }^{5 } }} cycles at 1000N in water. On the other hand contacts at {{{{ {10 }^{6 } }} cycles at 1000 N in water did show some signs of incipient degradation. By contrast contacts with Vickers indenter pro-duced substantial strength losses at much lower loads suggesting that the mechanical integrity of this ma-terial would be compromised by inadvertent sharp contacts.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2511-2514
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• 2008

As the minimum feature size decreases, techniques to avoid contamination and processes to maintain clean wafer surfaces have become very important. The deposition and detachment of nanoparticles from surfaces are major problem to integrated circuit fabrication. Therefore, cleaning technology which reduces nanoparticles is essential to increase yield. Previous megasonic cleaning technology has reached the limits to reduce nanoparticles. Megasonic cleaning is one of the efficiency method to reduce contamination nanoparticle. Two major mechanisms are active in a megasonic cleaning, namely, acoustic streaming and cavitation. Acoustic streaming does not lead to sufficiently strong force to cause damage to the substrates or patterns. Sonoluminescence is a phenomenon of light emission associated with the cavitation of a bubble under ultrasound. We studied a correlation between sonoluminescence and sound pressure distribution for the minimum of pattern damage in megasonic cleaning.

• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.114-122
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• 2024

Irradiation-induced defects and the precipitates in the wrapper material of the Indian Fast Breeder Test Reactor (FBTR), SS 316 are analyzed using the synchrotron source-based Angle Dispersive X-Ray Diffraction (ADXRD) technique with X-rays of energy 17.185 keV (wavelength ~0.72146 Å). The differences and similarities in the high displacement damage samples as a function of dpa (displacement per atom) and dpa rate in the range of 2.9 × 10^-7- 9 × 10^-7 dpa/s are studied. Ferrite and M₂₃C₆ are commonly observed in the present set of high displacement damage 40-74 dpa SS 316 samples irradiated at temperatures in the range of 400-483 ℃. Also, the dislocation density has increased as a function of the irradiation dose. The X-ray diffraction peak profile parameters quantified such as peak shift and asymmetry show that the irradiation-induced defects are sensitive to the dpa rate-irradiation temperature combinations. The increase in yield strength as a function of displacement damage is also correlated to the dislocation density.