• Journal of the Korean Society of Tobacco Science
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• v.24 no.1
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• pp.7-12
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• 2002

During the screening or antiviral substances having inhibitory effect on tobacco mosaic virus(TMV) infection to tobacco plants, we found that a bacterial isolate, KTB61, which was identified as a Pseudomonas sp., strongly inhibited the formation of TMV local lesions. When the culture filtrate from KTB61 was applied on the upper surface of leaves of N. tabaccum Xanthi-nc tobacco at the same time of or 24 hours before TMV inoculation, almost complete inhibition was achieved. Incidence of systemic TMV infection to the susceptible tobacco cultivar, NC82, was reduced by 95% when TMV was inoculated onto the upper surface of leaves 24 hours after spraying the culture filtrate. Also 75∼80% of inhibitory effect was obtained by the inoculation of TMV onto the under surface of the leaves treated with culture filtrate 24 hours beforehand. In field trials, the TMV infection was reduced by 96.5% when the tobacco seedlings, N. tabaccum cv. NC82, were soaked with culture filtrate before transplanting.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.1
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• pp.17-19
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• 2003

The purpose of this study was to evaluate the effect of pesticides on insect pest control of Rhophalosiphum nymphaeae, growth characteristies and dry root yield from the cultivated after early maturing rice cropping. All pesticides treated had no effect on the growh period, flowering rate of Alisma plantago. The major pesticides were methomyl-Lf, 24.1 %, imidacloprid-Wp, 10%, carbosulfan-Wp, 20%, and methomyl-Wp, 45%. Dry yield of root were increased largely with imidacloprid-Wp, 10% (10g/20$\ell$), pesticide than the other pesticides and control. All pesticides were had no injury with recommended concentration. On the other hand all pesticides were slightly harmful in the double dosage level for the Alisma plantago.

• Proceedings of the Optical Society of Korea Conference
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• 1995.06a
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• pp.138-148
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• 1995

A reduced description of the dynamics of carriers in excited semiconductors is presented. Fristly, a time-convolutionless equation of motion for the reduced density operator is derved from the microscopic Liouville wquation operator method. Secondly, the quantum kinetic equations for intercting electron-hole parirs near band-edge in semiconductors under an extermal optical field are obtained from the equation of motion for the reduced density operator. The non-Markovian optical gain of a driven semiconductor is derived including the many-body effects. plasma screening and excitinic effects are taken into account using as effective Hamiltonian in the time-dependent Hartree-Fock approximation. it is shown that the line shape of optical-gain spectra gain is enhanced by the exicitonic effects caused by the attrative electron-hole Coulomb interaction and the interference effects (renormalized memory effects) between the extermal driving filed and the intermal driving Filed and the stochastic reservoir of the system.

• Journal of Integrative Natural Science
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• v.4 no.4
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• pp.255-265
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• 2011

Marine ecosystems are often characterized by a high biological diversity, and it corresponds to a high chemical diversity. Up to present, more than 20,000 new bioactive substances have been isolated from marine organisms, where considerable numbers of these naturally occurring derivatives are developed as potential candidates for pharmaceutical application. In this process, screening of natural products from marine organisms that could potentially inhibit the expression of metalloproteinases has gained a huge popularity. Cancer is considered as one of the deadliest diseases in the medical field. Matrix metalloproteinase (MMPs) can degrade extracellular matrix (ECM) components and play important roles in a variety of biological and pathological processes. Matrix metalloproteinase inhibitors (MMPIs) have been identified as potential therapeutic candidates for metastasis, arthritis, chronic inflammation and wrinkle formation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.2
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• pp.332-334
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• 2009

The magnetic properties in YBCO superconducting materials were studied. In the measurement of I-V properties, it was cleared that the mechanism of magnetic properties could not be explained by using conventional flux theory. By changing the density of external magnetic flux, changes in current voltage characteristics in which a superconducting material were also measured. The results showed that the magnetic flux is generated by a vortex current which circulates around the vortex with a sense of rotation opposite to that of the diamagnetic screening surface current. When the external magnetic field was applied to the superconducting magnetometer, some regions of the magnetometer will be destroyed, especially the weak link regions and the defect regions.

• IE interfaces
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• v.20 no.1
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• pp.87-93
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• 2007

Burn-in is an engineering method for screening out products containing reliability defects which would cause early failures in field operation. Previously, various burn-in models have been proposed mainly focused on the trade-off of shop repair cost and warranty cost ignoring manufacturing yield. From the view point of a manufacturer, however, burn-in decreases warranty cost at the expense of yield reduction. In this paper, we provide a general model quantifying a trade-off between product yield and reliability, in which any defect distribution from previous yield models can be used. A profit function is expressed in burn-in environments for determining an optimal burn-in time. Finally, the method is illustrated with gate oxide failures which is an important reliability concerns for VLSI CMOS circuits.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.04a
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• pp.100-108
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• 1999

rectangular open or in-filled trenches(concrete and rubber) are often used to reduce the ground vibrations caused by propagating surface(Rayleigh) waves. This paper presents the experimental data for estimating the vibration screening effectiveness of open or in-filled trenches Field dynamic tests using the exciter which can generate the 100kN vertical cyclic load in the range of 100-250 Hz were performed. One hundred and twenty accelerometers to measure the ground response are used in 6 radial direction. To compare the effectiveness of the vibration isolation the contours of the amplitude ratio with the dimensionless parameters dividing by Rayleight wave lengths were presented.

• Journal of Sensor Science and Technology
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• v.22 no.4
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• pp.281-285
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• 2013

In this study a biosensor was developed by using Drosophila cells expressing a gustatory receptor Gr5a and an ion sensitive field effect transistors (ISFETs) sensor device, which demonstrated significant compatibility with the Drosophila cells expressing Gr5a and their response to sugar. These results suggested that the newly developed cell based biosensor has a potential as a simple and easy screening device for Alzheimer's disease in the future.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.942-945
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• 2008

There have been concerns about possible pathogenicity and antimicrobial resistance in Enterococcus, which constitute more than 50% of probiotics in the worldwide market. In this study, Enterococcus in sixteen products manufactured by ten different companies was tested for the presence of six virulence genes and two vancomycin resistance genes. Results in this study showed the safety of Enterococcus on the Korean market and the importance of screening vanA, vanE, agg, cylA, esp, and gelE. Pulse-field gel electrophoresis showed that the sixteen isolates tested in this study are originated from three strains.

• International Journal of Industrial Entomology and Biomaterials
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• v.12 no.1
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• pp.35-39
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• 2006

Fifty-six indigenous and twenty nine exotic mulberry varieties were screened against powdery mildew, Myrothecium leaf spot, Pseudocercospora leaf spot, sooty mold and bacterial leaf spot for a period of three years under field condition. The percent disease index (PDI) was recorded during peak season of the foliar diseases. Out of eighty-five varieties studied, ten varieties were highly resistant and eight were resistant to powdery mildew; six varieties were immune and seventy-eight varieties were highly resistant to Myrothecium leaf spot; sixty varieties were highly resistant and 21 were resistant to Pseudocercospora leaf spot; forty four varieties were highly resistant to sooty mold and two varieties were immune and fifty-eight were highly resistant to bacterial leaf spot. Lowest cumulatative disease index was observed in M. multicaulis (7.28) followed by Thailand lobed (7.85) and Italian mulberry (8.06).