• Journal of Ocean Engineering and Technology
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• v.33 no.3
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• pp.222-228
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• 2019

An extreme value analysis (EVA) is essential to obtain a design value for highly nonlinear variables such as long-term environmental data for wind and waves, and slamming or sloshing impact pressures. According to the extreme value theory (EVT), the extreme value distribution is derived by multiplying the initial cumulative distribution functions for independent and identically distributed (IID) random variables. However, in the position mooring of DNVGL, the sampled global maxima of the mooring line tension are assumed to be IID stochastic variables without checking their independence. The ITTC Recommended Procedures and Guidelines for Sloshing Model Tests never deal with the independence of the sampling data. Hence, a design value estimated without the IID check would be under- or over-estimated because of considering observations far away from a Weibull or generalized Pareto distribution (GPD) as outliers. In this study, the IID sampling data are first checked in an EVA. With no IID random variables, an automatic resampling scheme is recommended using the block maxima approach for a generalized extreme value (GEV) distribution and peaks-over-threshold (POT) approach for a GPD. A partial autocorrelation function (PACF) is used to check the IID variables. In this study, only one 5 h sample of sloshing test results was used for a feasibility study of the resampling IID variables approach. Based on this study, the resampling IID variables may reduce the number of outliers, and the statistically more appropriate design value could be achieved with independent samples.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.23-28
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• 2007

Auxin-producing antagonistic bacterium K11, which can inhibit Phytophtora capsici, was isolated from a local red-pepper field soil in Gyeong-buk. In order to check for additional PGPR(plant growth promoting rhizobacterium) functions of the strain K11, we confirmed siderophore and cellulase productions by CAS (chrome azurol S) blue agar and CMC plate with congo red, respectively. The strain K11 was identified as Bacillus licheniformis with 98% similarity on 16s rDNA comparison and Biolog analyses. B. licheniformis K11 promoted mung bean adventitious root induction and enhanced root growth of mung bean (160%), pea (150%), and Chinese cabbage (130%), Also, B. licheniformis K11 was able to effectively suppress (63%) P. capsici causing red-pepper blight in the pot in vivo test. Therefore, we could select a triple-functional PGPR which has auxin, siderophore, and cellulase producing ability for effective crops production in organic farming.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.3
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• pp.265-273
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• 1984

To investigate nitrogen supplying effect of some slowrelease N-fertilizers on barley in upland soil sulfurcoated urea(SCU), ureaform and melamine (1,3,5-Triazine-2,4,6-triamine) were treated and compared to urea. In addition, thiourea as a nitrification inhibitor was also tested. Effects of variable soil condition such as moisture content, pH and temperature on nitrogen supplying ability of the fertilizers and on growth of barley were studied through incubation test and pot culture and the obtained results were summarized as follows: The releasing rate of ammonia from urea, SCU, ureaform and melamine were resulted as 27-59%, 25-39%, 9-34% and 0.7-4.3% at maximum conversion rate, respectively. Nitrification rate of the tested fertilizers was higher at pH 6.54 markedly than at pH 4.73. Addition of thourea depressed the formation of $NO_3$ during four weeks of incubation period. Mixed application of ureaform with small amount of urea contributed to nitrogen supply till latter growth stage of barely Basal application of melamine showed lowest nitrogen supplying ability and injurious response on barley growth.

• Research in Plant Disease
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• v.16 no.1
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• pp.41-47
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• 2010

A total of 10,753 oligotrophic bacteria were isolated from the cultivated soils of red-pepper infected by Phytophthora blight disease in various regions of Korea (Chungju, Anmyon, Taean, Andong, Eumsung and Goesan). Seven bacteria isolates among these collected resources were selected by the first screening of in vitro antagonistic assay against major several plant pathogenic fungi including Phytophthora capsici. Finally, strain 7F was selected by pot assay for a possible biological control agent against Phytophthora blight disease of pepper seedling in the greenhouse. Strain 7F was identified as Bacillus subtilis on the basis of its 16S rDNA sequence analysis and as standardized biochemical characteristics assay kits such as API20 NE. In the experiment of P. capsici zoospore infected red-pepper on the pot test, infection rate of red-pepper with nonetreatment to Phytophthora blight disease was 87%, while the rate was only 6% in the pot treated with strain 7F. This result indicated that the Bacillus subtilis strain 7F will be useful as a potential biocontrol agent for Phytophthora blight disease of red-pepper.

• Journal of Life Science
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• v.18 no.6
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• pp.858-864
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• 2008

In the greenhouse fields for fruits and vegetables during the winter in Korea, there are serious damages by the sclerotium diseases due to the low temperature and humidity. This study was carried out to select an antagonic agent for the biological control of the sclerotium diseases. The 55 antagonic agents were selected from the rhizosphere in soil where the fruits and vegetables were cultivated in the green house fields, and strain AB02 among the tested isolates was estimated to be the strongest antagonist against the sclerotium disease. Using strain AB02, the antifungal spectrum was tested against 5 different plant pathogens. According to the results of the test, strain AB02 . showed the high antagonistic effect against Botrytis cinerea and Sclerotinia sclerotiorum. For the experiment of biological control against the sclerotium disease, it was estimated the suppression effect and the control effect by the strain in the pot experiment using the green perilla. According to the result of the pot experiments, the suppression effect was 40% and the control effect was 62%, respectively. For the stimulation effect of the tested plant growth by strain AB02 compared to the control, it was improved as 120% for the total length, 141% for the liveweight, 121% for the total number of leaves, 185% for the leaf area, and 327% for the liveweight of the root, respectively. Strain AB02 showing the antagonistic effect against the sclerotium disease and the stimulation effect for the plant growth was identified as Bacillus sp.

• Applied Biological Chemistry
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• v.8
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• pp.65-73
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• 1967

For the study of method for salt elimination aimed at reforming tidal land into normal paddy fields in a short period with reduction of periods requiring for elimination of saline, CHP (a kind of Ca-hum ate), a soil conditioner made of peat as a main material was tried. In the pot experiment, effect on elimination of salt, improvement of physical-chemical characteristics and rice cultivation test were studied. The results of these tests are as follows: 1, CHP treatment somewhat improves aggregation state with some effect on aggregation. 2. CHP treatment is remarkably effective in permeability which increases with 1.0 percent treatment by three times in percolation rate, and by 4.5 times in volume of leached water respectively. 3. With the increase of CHP amounts, salt was eliminated in short period. When 80% of the total Na was leached in 1.0% CHP-A treated pot, control pot begins permeable. 4. CEC and phosphorous absorption capacity are not influenced by CHP treatment. 5. Growing state of rice is greatly influenced by rainfalls. Growth of rice in tidal land however are almost similar to those in normal paddy fields with layer amounts of CHP treatment. With salt content in the soils, saline hazard and numbers of ineffective stems, amounts of unmatured grain are increased. 6. With the treatment of CHP yields of rough rice were increased. With 0.5% CHP treatment the yields were similar to those of the normal paddy fields. With 1.0% CHP-A treatment, the yields were increased by 15 times more than those of none treated soil and by 25 percent more than normal paddy soils.

• The Plant Pathology Journal
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• v.18 no.4
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• pp.221-224
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• 2002

In vitro and in vivo activities of a biocontrol agent, Serratia plymuthica strain A2l-4, was evaluated for the control of Phytophthora blight of pepper, Strain A2l-4 inhibited mycelial growth, germination of zoosporangia and cystospores, and formation of zoospore and zoosporangia of Phytophthora capsici in vitro. In the pot experiment, incidence of Phytophthora blight of pepper in non-treated control was 100% at 14 days after inoculation, while no disease was observed in the plot treated with S. plymuthica A2l-4. In the greenhouse test, infection rate of pepper in the non-treated plots was 74.5%, while it was only 12.6％ in the plots treated with A2l-4. Results indicate that S. plymuthica A2l-4 is a potential biocontrol agent for Phytophthora blight of pepper.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.79.1-79
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• 2003

Two pathogen-induced hot pepper transcription factors (CaNACl and CapIfl) were introduced into‘MicroTom’tomato by Agrobacterium tumefaciens-mediated transformation. We used to nptII containing kanamycin resistance gene as a selection marker. Both transformed and non-transformed plants were transferred to pot after rooting test in vitro. To approximate the levels of caNACl transcript in leaves of wild-type and transgenic plants, RNA blots were hybridized with double-stranded full-length CaNACl probe at moderate stringency, Although the relative signal strength for hybridization fluctuated among the samples on different blots, transgenic plant lines N-1, N-2 and N-3 consistently displayed increased levels of CaNACl transcript relative to other transgenic lines and wild-type plants. Of all the transgenic lines examined, line N-7 had the least amount of CaNACl transcript. Role of these transcription factors in pathogen defense will be examined by overexpression in tomato.

• Microbiology and Biotechnology Letters
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• v.23 no.1
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• pp.91-97
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• 1995

The 543 microbial strains were isolated from the rhizosphere in ginseng root rot-suppressive soil. From these, isolate KGM-100 was finally selected for the screening of powerful antagonistic bacterium for the soil-born Fusarium solani causing root rot of many important crops. The isolate KGM-100 was identified as Pseudomonas aeruginosa. Antibiotics produced by the P. aeruginosa KGM-100 were partially characterized as heat-stable and low-molecular weight antibiotics. The strain also produced siderophore, which was assumed to be pseudobactin. Pot test showed approximately 30-50% biological control effects when Fusarium solani-infected soil was treated with the P. aeruginosa KGM-100.

• Journal of the Korean Applied Science and Technology
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• v.22 no.1
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• pp.1-8
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• 2005

Chlorine-containing modified polyester polyols were synthesized by two-step condensation reactions. Intermediate was synthesized by the esterification of monochloroacetic acid with trimethylolpropane in the first step. Polycondensation of the intermediate (MCAOs), 1,4-butanediol, and trimethylolpropane with adipic acid was carried out. Two-component polyurethane (PU) coatings were prepared by blending MCAOs and IPDI-isocyanurate. There new flame-retardant coatings showed various properties comparable to other non-flame-retardant coatings. They were superior to flammable coatings from the experimental results showing rapid and 10 to 13 hours of pot-life. Coatings with 30wt% monochloroacetic acid was not flammable by the vertical flame retardancy test.