• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.621-626
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• 1998

An experimental investigation on the reinforcing bar corrosion and relationshid of reinforcing bar and concrete bond strength has been conducted to establish the allowable limit of rust in the construction field. The reinforcing bars used in this study were rusted before embedding in concrete. The first component of this experiment is to make rust of reinforcing bar rust artificially based on Faraday's theory at certain rates such as 2, 4, 6, 8 and 10% of reinforcing bar weight. For estimation of the amount of rust by weight, Clarke's solution and Shot blasting were adopted and compared. Parameters include 240 and 450kg/㎠ of compressive strengths and diameter of reinforcing bar (16, 19 and 25mm) corresponding development length for pull-ort test. And, pull-out tests were carried. out according to KSF 2441 and ASTMC 234 to investigate the effect of the corrosion rate on reinforcing bar-concrete bond behavior. It is found from the test results that the test techniques for corrosion of bar used in this study is relatively effective and correct test method. Results shows that up to 2% of rust increases the bond strength regardless of concrete strength and diameter of reinforcing bar like the existing data. It might be because of the roughness from rust. As expected, the bond strength increases as compressive strength of concrete increases and the diameter of bar decreases.

• Journal of Ginseng Research
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• v.21 no.2
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• pp.69-77
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• 1997

In order to explain the connection between ginseng rust spot and soil ecological conditions, the bed soils and ginseng roots were sampled at different microrelief units and the reducing substances of the bed soils and iron forms of the ginseng root epi dermises were determined. The results showed that the occurrence of the rust spot was connected with the ecological conditions of the soils and the metabolism of the plant which was caused by the excessive $Fe^{2+}$ in the soil solution. Ginseng rust spot was the enrichment of iron which was mainly composed of organic complex irons. Including active ferrous active ferric and non active ferric forms and they were transformed into each other following the change of soil moisture and temperature regimes. According to the regularity of growth and decline of reducing substances in soil and rust index of ginseng roots as well as the difference of adaptability to excessive $Fe^{2+}$ in soil among different year-old seeding, a new comprehensive measure based on the connection of ameliorating soil and improving cultivation system was recommended to prevent the occurrence of ginseng rust spot.

• Mycobiology
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• v.50 no.3
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• pp.166-171
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• 2022

Virginia creeper (or five-leaved ivy; Parthenocissus quinquefolia) is one of the most popular and widely grown climbers worldwide. In September 2021, Virginia creeper leaves with typical rust symptom were found in an arboretum in Korea, with severe damage. Globally, there is no record of a rust disease on Virginia creeper. Using morphological investigation and molecular phylogenetic inferences, the rust agent was identified as Neophysopella vitis, which is a rust pathogen of other Parthenocissus spp. including Boston ivy (P. tricuspidata). Given that the two ivy plants, Virginia creeper and Boston ivy, have common habitats, especially on buildings and walls, throughout Korea, and that N. vitis is a ubiquitous rust species affecting Boston ivy in Korea, it is speculated that the host range of N. vitis may recently have expanded from Boston ivy to Virginia creeper. The present study reports a globally new rust disease on Virginia creeper, which could be a major threat to the ornamental creeper.

• Proceedings of the Korea Information Processing Society Conference
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• 2021.05a
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• pp.151-154
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• 2021

Rust is a promising system programming language that made its debut in 2010. It was developed to address the security problems in C/C++. It features a property called ownership, on which it relies to mitigate memory attacks. For this and its many other features, the language has consistently gained popularity and many companies have begun to seriously consider it for production uses. However, Rust also supports safe and unsafe regions under which the foreign function interface (FFI), used to port to other languages, falls. In the unsafety region, Rust surrenders most of its safety features, allowing programmers to perform operations without check. In this study, we analyze the security issues that arise due to Rust's safety/unsafety property, especially those introduced by Rust FFI.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.440-446
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• 1986

The physiological reaction of two soybean (Glycine max (L.) Merrill) cultivars tolerant and susceptible to rust (Phakopsora pachyrhizi Syd.) was studied at the AVRDC in Taiwan, ROC. The rust epidemic on the susceptible cultivar began earlier and progressed more rapidly than on the tolerant cultivar. The defoliation by rust infection increased rapidly after the latter half of pod filling. The reduction of LA! by rust in the susceptible cultivar occurred earlier than in the tolerant cultivar. The differences in the chlorophyll content between the rust-free and rust-infected plants was 2.04% in the tolerant, and 16.43% in the susceptible cultivar. The shoot dry weight increased at each growth stage in the fungicide protected plots, but decreased in the non-fungicide protected plots after the R6 growth stage onward and the tendency to decrease was more severe in the susceptible than in the tolerant cultivar. The pod and seed dry weight of the suscep-tible cultivar in the fungicide-protected plot increased dramatically from the R6 growth stage, but in the non-fungicide plot, there was almost no increase in pod and seed dry weight from R6 growth stage, due to rust. The number of empty pods and imperfect grains were increased by rust infection, but the protein content was not afftected. There were reductions of oil content, seed length, seed width, seed thickness, pod thickness, number of pods and seeds, 100 seed weight, and yield due to rust infection. The yield losses by rust infection were 22.3%in the tolerant and 68.7% in the susceptible cultivar.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2063-2068
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• 2013

Ship and offshore structures, those are to be used under the seawater conditions are prone to corrosion. In this research, the effect of rust existence on the fatigue strength at structural member of ship and offshore structure was investigated. For this purpose, fatigue tests for the rust removed specimen were conducted. In addition, the comparison of fatigue strength between rust removed specimen and rusted specimen was conducted. With these test results, fatigue strength share effect was investigated. Finally, at this research, it was found that there is fatigue strength share effect on the rust. In comparison of fatigue strength reduction factor, fatigue strength of the rust removed specimen is 18.1% lower than that of the rusted specimen. From the above, it was known that as far as there are not any harmful ingredients in it, rust on the steel plate is beneficial in an aspect of fatigue strength.

• The Plant Pathology Journal
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• v.31 no.3
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• pp.299-304
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• 2015

Interaction of the the rust fungus Puccinia miscanthi with the biofuel plant Miscanthus sinensis during the teliospore phase was investigated by light and electron microscopy. P. miscanthi telia were oval-shaped and present on both the adaxial and abaxial leaf surfaces. Teliospores were brown, one-septate (two-celled), and had pedicels attached to one end. Transmission electron microscopy revealed numerous electron-translucent lipid globules in the cytoplasm of teliospores. Extensive cell wall dissolution around hyphae was not observed in the host tissues beneath the telia. Hyphae were found between mesophyll cells in the leaf tissues as well as in host cells. Intracellular hyphae, possibly haustoria, possessed electron-dense fungal cell walls encased by an electron-transparent fibrillar extrahaustorial sheath that had an electron-dense extrahaustorial membrane. The infected host cells appeared to maintain their membrane-bound structures such as nuclei and chloroplasts. These results suggest that the rust fungus maintains its biotrophic phase with most mesophyll cells of M. sinensis. Such a nutritional mode would permit the rust fungus to obtain food reserves for transient growth in the course of host alteration.

• Korean Journal of Microbiology
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• v.19 no.3
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• pp.108-114
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• 1981

In order to isolate microorganisms which produce antibiotics aganist wheat black rust, some bacteria, molds, and actinomycetes were isolated from soils and screened for the production of antibiptics against wheat black rust. Beacuse wheat black rust-puccinia graminis--is a complete parsitic mold which can't grow in artifical medium, new method for the screening of antibiotic producing microorgsnisms against wheat black rust developed by using live leaves of wheat. With new method, a strain No. $480HS_{20}$ which produces a substnace having strong and Puccinia graminis activity and very narrow antimicrobial spectrum was isolated. the substance produced by the strain No.$480HS_{20}$ had better anti Puccinia graminis activity than any other known antifungal antibotics such as kasurgamycin, balasticidins, actidione, antimycin, ologomycin. And the substance was observed to be very stable at heat and ultraviolet light. The strain was indentified as Bacillus subtilis.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.82-82
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• 2014

마감 도장이 완료된 면이 장기간 노출된 상태에서 후속 작업으로 인해 금속 분진 등의 오염물이 쌓이면 수분 및 염분 등과의 반응으로 도장 표면에 녹 등의 2차 오염이 발생하여 광택이나 표면 미려함 등을 잃어버리게 된다. 이럴 경우 소요되는 시간과 경비를 줄이기 위해 재도장 작업 대신 도장 표면의 오염 막을 제거하기 위한 방법으로 rust remover가 사용되고 있으나, 현재 rust remover 사용에 따른 도막 열화에 관한 객관적인 자료가 없는 실정이다. 본 연구에서는 당에서 사용되고 있는 선박용 마감 도료를 대상으로 rust remover가 도막 표면 열화에 미치는 영향에 대하여 조사 검토하다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.1
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• pp.188-194
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• 2001

A reinforced concrete structure is complex structure that works as one body with bonding role of steel bar and concrete. The bonding action between steel bar and concrete makes possible the compound structure. The transmission of mutual strength of the steel bar with concrete in structure is determined by the bonding characteristic of steel bar and concrete surface. But the efficiency of bonding characteristic of steel bar is Questionable by the corrosion cause by the delay construction term, the wrong management, etc. So this study investigate bonding characteristic of reinforced concrete using pull-out test method which steel bar removed rust and the principal variables of this study are concrete compression strength and the degree of corrosion. The result showed that bonding strength tend to increase when removed rust of steel bar whereas it tend to decrease when not removed rust.