• 한국응용곤충학회지
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• 제41권3호
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• pp.217-223
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• 2002

주둥무늬차색풍뎅이는 성충이 각종 활엽수의 잎을 가해하여 피해를 주는 해충이지만 유충에 의한 피해도 벤트그라스에서 기록되어 있다. 그러나 진주골프장의 퍼레니얼라이그라스에서 7월에 잔디가 황화 현상을 보이면서 시들음 증상이 나타나 조사한 결과, 주둥무의차색풍뎅이 유충에 의한 피해로 확인되었다. 피해는 한지형 잔디의 하고현상과 비슷하나 관수 후에도 잔디의 활력이 회복되지 않고, 부분적으로 고사가 일어나는 차이를 보였다. 한편, 주둥무의차색풍뎅이 유충의 환경친화적 방제를 위하여 한국산 곤충병원성 선충의 효과를 실험실과 골프장에서 수행하였다. 실험실내에서 주둥무의차색풍뎅이 3령충은 Heterorhabditis bacteriophora 제주 strain과 Hererorhabditis sp. 경산 strain, Steinernema carpocapsae 포천 strain, S.glaseri 동래 strain, S.longicaudum 논산 strain 중 H.bacteriophora 제주 strain과 Heterorhubditis sp. 경산 strain에 의한 치사율이 95%로 가장 높았다. 골프장 fairway에서의 야외실험에서는 H. bacreriophora제주 strain과 Heterorhabditis sp. 경산 strain, S.carpocapsae 포천 strain에 의한 유충 감소율이 28-57%로 다양하였다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2009년 추계학술발표대회
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• pp.202-204
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• 2009

Erosion is a common failure mode of materials frequently encountered in plant and power industry. Although the erosion resistance of Fe-base alloy has been inferior to the other expensive materials, it is expected that the strain-induced martensitic transformation can impart high erosion resistance to Fe-base alloy. The key technology to develop Fe-base metal cored welding wire for erosion resistant overlay welding may include the strain-induced metallurgy for hardening rate control and the welding flux metallurgy for dilution control. Sophisticated studies showed that the strain-induced martensitic transformation behavior was related to the critical strain energy which was dependent on the alloy composition. Dilution and bead shape of overlay weld were proved to be affected by metal transfer mode during gas tungsten arc welding and elements in welding fluxes. It was considered that the highly erosion resistant Fe-base overlay weld could be achieved by precise control of alloy composition to have proper level of critical strain energy for energy absorption and welding flux formulation to have small amount of deoxidizing metallic elements for dilution.

• The Plant Pathology Journal
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• 제25권4호
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• pp.333-343
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• 2009

Here, we show that an endophytic bacterial strain, Enterobacter asburiae B1 exhibits the ability to elicit ISR in cucumber, tobacco and Arabidopsis thaliana. This indicates that strain B1 has a widespread ability to elicit ISR on various host plants. In this study, E. asburiae strain B1 did not show antifungal activity against tested major fungal pathogens, Colletotrichum orbiculare, Botrytis cinerea, Phytophthora capsici, Rhizoctonia solani, and Fusarium oxysporum. Moreover, the siderophore production by E. asburiae strain B1 was observed under in vitro condition. In greenhouse experiments, the root treatment of strain B1 significantly reduced disease severity of cucumber anthracnose caused by fungal pathogen C. orbiculare compared to nontreated control plants. By root treatment of strain B1 more than 50% disease control against anthracnose on cucumber was observed in all greenhouse experiments. Simultaneously, under the greenhouse condition, the soil drench of strain B1 and a chemical inducer benzothiadiazole (BTH) to tobacco plants induced GUS activity which is linked with activation of PR promoter gene. Furthermore, in Arabidopsis thaliana plants the soil drench of strain B1 induced the defense gene expression of PR1 and PDF1.2 related to salicylic acid and jasmonic acid/ethylene signaling pathways, respectively. In this study, for the main focus on root colonization by strain B1 associated with defense responses, bacterial cells of strain B1 was tagged with the gfp gene encoding the green fluorescent protein in order to determine the colonization pattern of strain B1 in cucumber. The gfp-tagged B1 cells were found on root surface and internal colonization in root, stem, and leaf. In addition to this, the scanning electron microscopy observation showed that E. asburiae strain B1 was able to colonized cucumber root surface.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.103.1-103
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• 2003

An antagonistic bacteria, Stenotrophomonas maitophilia BW-13 strain which was effectively inhibited mycerial growth of Bottom rot pathogen, Rhizoctonia solani PY-1 strain was isolated from the rhizosphere of the lettuce in Uiryeong-Gun, Gyeongsangnam-Do from 2002 to 2003. For the biological control, the most suitable inoculum and its density of pathogen, PY-1 strain ware tested prior biological control test, For the pathogenicity test, A inoculum (wheat bran)sawdust+rice bran+PDB) showing disease incidence of 100％ was selected as the most suitable inoculum, which showed more effective than B inoculum (sawdust＋rice bran＋DW) and mycelial disc. also, In selection of the amount of inoculum (40g, 50g, 60g, 70g, 80g), most suitable amount of inoculum of pathogen determined as 40g showing disease incidence of 80％. For the selection of effective microorganism to control bottom rot on lettuce, about 200 isolates were isolated from the diseased soil and lettuce leaves, and examined their antifungal activity to the pathogen on PDA. As the pots assay, BW-13 strain showed the highest control value as 90％, and followed by R-13 and R-26 strain as 80％ and 60％, respectively. Selected BW-13 isolates identified as 5. maltophilia (GeneBank accession no. AJ293473.1, 99％) by 16S rRNA sequencing. This is the first report on the biological control using by S. maltophilia to the bottom rot pathogen, Rhizoctonia solani PY-1 strain.

• 한국미생물·생명공학회지
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• 제25권4호
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• pp.396-402
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• 1997

Biocontrol of plant pathogens provides an alternative means of reducing the incidence of plant diseases without the negative aspects of chemical pesticides. Nowdays, as the resistant fungi about the chemical fungicides have revealed and the concern of environment has increased, the biological control of phytopathogenic fungi by the antagonistic microorganisms is very much indispensable. For the selection of strong antagonistic bacterium for biological control agent of rice leafblast and cucumber gray mold rot, the antifungal strain KL-3 strain was selected among 120 strains isolated from the rhizosphere soils. And the strain was identified to be a species of Bacillus subtilis or closely related strain. In several biochemical and in vitro antibiosis tests, antifungal substances of Bacillus sp. KL-3 were presumed heat stable, micromolecular antibiotic substances. In vivo test and vinyl house field test, the antifungal substances of Bacillus sp. KL-3 represented excellent biocontrol ability aganist Alternaria mali, Phyricularia oryzae, and Alternaria kikuchiana as well as broad spectrum of other fungi. In particular, Bacillus sp. KL-3 strain showed more predominant activity than some chemical fungicides against fungi shown to resist chemcal fungicides.

• 한국지반공학회지:지반
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• 제13권2호
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• pp.29-38
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• 1997

암석과 같은 지반재료를 전단하게 되면 응력-변형률관계에서 변형률연화현상이 관찰되어진다. 변형률연화현상은 지반공학문제에서 논하고 있는 파괴거동현상과 밀접한 관계가 있으므로 그 거동을 묘사할 수 있는 수치해석방법의 확립이 중요하다. 본 논문에서는 대변형 탄소성유한요소법을 이용하여 지반재료의 파괴거동를 묘사하기 위해서 재료의 연화성질을 도입하여 해석하는 경우, 고려해야 할 요소의 선택, 배치, 초기부정의 영향, 미소변형과 대변형 해석의 차이, 최고점 하중후의 하중제어를 하기 위한 변위제어 및 압력제어의 차이에 대하여 검토하였다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1994년도 Proceedings of International Symposium on BIOLOGICAL CONTROL OF PLANT DISEASES Korean Society of Plant Pathology
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• pp.11-26
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• 1994

Crown gall of stonefruit and nut trees is one of the very few plant diseases subject to efficient biological control. The disease is caused by the soil-inhabiting bacteria Agrobacterium tumefaciens and Agrobacterium rhizogenes and the original control organism was a non-pathogenic isolate of A. rhizogenes strain K84. Control is achieved by dipping planting material in a cell suspension of strain K84 which specifically inhibits pathogenic strains containing a nopaline Ti plasmid. Because the agrocin 84-encoding plasmid (pAgK84) is conjugative, it can be transmitted from the control strain to pathogenic strains which, as a result, become immune to agrocin 84 and cannot be controlled. To prevent this happening, the transfer genes on pAgK84 were located and then largely eliminated by recombinant DNA technology. The resulting construct, strain K1026, is transfer deficient but controls crown gall just as effectively as does strain K84. Field data from Spain confirm that pAgK84 can transfer to pathogenic recipients from strain K84 but not from strain K1026. The latter has been registered in Australia as a pesticide and is the first genetically engineered organism in the world to be released fro commercial use. It is recommended as a replacement for strain K84 to prevent a breakdown in the effectiveness of biological control of crown gall. Several reports indicate that both strains K84 and K1026 sometimes control crown gall pathogens that are resistant to agrocin 84. A possible reason for this is that both strains produce a second antibiotic called 434 which inhibits growth of nearly all isolates of A. rhizogenes, both pathogens and non-pathogens. Crown gall of grapevine is caused by another species, Agrobacterium vitis. It is resistant to agrocin 84 and cannot be controlled by strains K84 or K1026. It is different from other crown gall pathogens in several characteristics, including the fact that, although a rhizosphere coloniser, its also lives systemically in the vascular tissue of grapevine. Pathogen free propagating material can be obtained from tissue culture or, less surely, by heat therapy of dormant cuttings. A number of laboratories are searching for a biocontrol strain that will prevent, or at least delay, reinfection. A non-pathogenic A. vitis strain F/25 from South Africa looks very promising in this regard.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1430-1433
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• 2003

Transducers, which are incorporated in control devices for fixed wing aircraft, land vehicles. and weapon systems were designed and manufactured by use of semiconductor strain gages. These transducers consist of three parts; flange mounts, sensing rods, and semiconductor strain gages. In this investigation, we designed cylindrical sensing rods with high sensitivity and developed installation procedures of semiconductor strain gages. The semiconductor strain gage has hish gage factor such that it can produce high resistance change in spite of low strain, but it is so small and fragile that one should handle carefully and sophisticated installation method is needed for good performances. The prototype transducers are manufactured, and then tested about three important factors: sensitivity, linearity, and hysteresis. We got results or 0.084 V/N sensitivity, 0.2% nonlinearity, and 0.5% hysteresis.

• Journal of Welding and Joining
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• 제12권4호
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• pp.151-161
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• 1994

FCAW has wide application in ship fabrication, maintenance and field erection. It has many advantages over SMAW.SAW and GMAW process. In many applications, the FCAW provides highquality weld metal. This method can reduce weld defects especially porosity and spatter. But the fatigue characteristics of those deposited metal have been rarely investigated. The purpose of this study is to investigate the cyclic stress-strain behavior and fatigue tests by the constant strain control were carried out on the rounded smooth specimen with deposited metal using the metal type flux cored wire. As the results of this study for the deposited metal welded by the metal type flux cored wire, the hardening or softening characteristics under cyclic load were investigated and cyclic stress-strain curve, strain-fatigue life curve, stress-strain function and fatigue life relation which are useful to estimate the fatigue life under the stress concentration condition were obtained.

• Journal of Microbiology and Biotechnology
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• 제24권10호
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• pp.1327-1336
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• 2014

Bacillus amyloliquefaciens strain NJZJSB3 has shown antagonism of several phytopathogens in vitro, especially Sclerotinia sclerotiorum. Both the broth culture and cell suspension of strain NJZJSB3 could completely protect the detached leaves of canola (Brassica napus) from S. sclerotiorum infection. In pot experiments, the application of strain NJZJSB3 cell suspension ($10^8CFU/ml$) decreased the disease incidence by 83.3%, a result similar to commercially available fungicide (Dimetachlone). In order to investigate the potential biocontrol mechanisms of strain NJZJSB3, the nonvolatile antifungal compounds it produces were identified as iturin homologs using HPLC-ESI-MS. Antifungal volatile organic compounds were identified by gas chromatography-mass spectrometry. The detected volatiles toluene, phenol, and benzothiazole showed antifungal effects against S. sclerotiorum in chemical control experiments. Strain NJZJSB3 also produced biofilm, siderophores and cell-wall-degrading enzymes (protease and ${\beta}$-1,3-glucanase). These results suggest that strain NJZJSB3 can be a tremendous potential agent for the biological control of sclerotinia stem rot.