• Journal of Life Science
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• v.7 no.4
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• pp.347-354
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• 1997

Some attempts were made to investigate the gentic characteristics of the brown planthopper(BPH), Nilaparvata lugens Sta${\aa}$l, biotypes. In terms of egg and nymphal periods, egg hatcgability, emergence ratio, and population change of BPH and plant damage of rice cultivars by the infestation of BPH biotypes and their hybrid progenies in field conditions. The egg and nymphal periods of the three of BPH biotypes and their hybrid progenies on Dongjinbyeo with no resistance gene were shorter than on rice cultivars with resistance gene. But the periods of biotype-2(♀) X 2(♂) (E) on Samgangbyeo with Bph-1 gene and biotype-3(♀) X 3(♂)(I) on Mirying 63 with bph-2 gene were as short as on Dongjinbyeo. The egg hatchability and emergence ratio of the three Bph biotypes and their hybrid progenies on Dongjinbyeo were higher than on the other rice cultivars, and those of E on Samgangbyeo and I on Miryang 63 were as high as on Dongjinbyeo. In rice paddy field, biotype-1(♀) X 1(♂)(A)$\sim$I infested on Dongjinbyeo, E onSamgangbyeo, and I on Miryang 63 were increased their population densities remarkably in next generation. Dongjinbyeo infested by A$\sim$I, and Myryang 63 infested by I were hopperburned at 60 days after infestation and had a damage rating of 0.9. But Samgangbyeo infested by E was no hopperburn(damage rating: 7.3) though it showed high BPH population at 60 days after infestation.

• Korean Journal of Optics and Photonics
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• v.1 no.1
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• pp.1-6
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• 1990

We studied two-photon-resonant three-photon ionization processes via 4D[channel #1] and 5S(channel #2] intermediate state of Na atom in a quartz ionization cell. For each channel. the bandwidth of ionization spectrum increased linearly with laser intensity and the ionization signal followed J3 dependence at low intensity. Compared with channel # 1 . ionization signal of channel #2 was enhanced by a factor of 20 - 25. The measured AC Stark shift factor of 3S - 4I) transition was $174\pm60MHz/MW/textrm{cm}^2$..

• Korean Journal of Poultry Science
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• v.15 no.1
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• pp.39-44
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• 1988

This study was undertaken to find out the effect of heating time and temperature, pH and NaCl concentration on heat sensitivity of egg albumen during heat treatment. Sharp increase of the turbidity and rapid decrease of the foaming power were observed when egg albumen was heated at above $60^{\circ}C$. Egg albumen became opaque when it was heated at $60^{\circ}C$ for above 13 minutes or at $65^{\circ}C$ for above 5 minutes. The turbidity was markedly increased at below pH 7 and the foaming power was largely decreased at around pH 4.0 by the heat treatment ($60^{\circ}C$, 5 min). The foam stability was slightly decreased at alkaline pH range by the heat treatment (60t, 5 min). The addition of NaCl up to 0.3M decreased the turbidity. There was no effect of NaCl addition on the foaming power, but the foam stability was decreased by the addition of NaCl at above 0.2M before and after the heat treatment ($60^{\circ}C$, 5 min).

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.1
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• pp.59-68
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• 2009

Fuel cell generators as the distributed generation system with a few hundred watt$\sim$a few hundred kilowatt capacity, can supply the high quality electric power to user as compared with conventional large scale power plants. In this paper, PEMFC(polymer electrolyte membrane fuel cell) generator as micro-source is modelled by using PSIM simulation software and DSP based fuel cell hardware simulator based on the PSIM simulation model is implemented. The relation of fuel cell voltage and current(V-I curve) is linearized by first order function on the ohmic area in voltage-current curve of fuel cell. The implemented system is composed of a PEMFC hardware simulator, an isolated full bridge dc boost converter, and a 60[Hz] voltage source PWM inverter. The voltage-current-power(V-I-P) characteristics of the implemented fuel cell hardware simulator are verified in load variation and transient state and the 60[Hz] output voltage sinusoidal waveform of the PWM inverter is investigated under the resistance load and nonlinear diode load.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1992.11a
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• pp.123-127
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• 1992

When MOS devices is exposed to radiation, radiation effects of P-type MOS capacitor can cause modulation and/or degradation in devices characteristics and its operating life. The oxide layer is grown in $O_2$+T.C.E. and its thickness ranges from 40 to 80 nm. Irradiations on MOS capacitor were performed by Cobalt-60 gamma ray source and total dose ranges from $10^4$ to $10^8$ rads. The radiation effect on electrical conduction characteristics(I-V) in MOS capacitor was measured as a function of gate oxide thickness and total dose. From the experimental result, I-V characteristics is found to be influenced strongly by total dose in irradiated p-type MOS capacitors. The ohmic current is dependant on of total dose in irradiated P-type MOS capacitors. This results are explained using surface states at interface radiation-induced traps.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.6
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• pp.111-117
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• 2009

The RUSLE(Revised Universal Soil Loss Equation) has been most widely used to estimate sediment yield in Korea. However RUSLE factors have not been verified based on measured data of sediment yield. The analysis of characteristics for the rainfall erosivity factor R was performed in this study. The R factor of RUSLE is expressed as multiple of total rainfall energy and maximum 30 min rainfall intensity. In this study, the characteristics of 10 rainfall energy equations were investigated using data measured in Gangneung experimental watershed, and applicability of each equations was reviewed based on results of the correlation analysis between measured sediment yield and total rainfall, between measured sediment yield and maximum intensity, and between measured sediment yield and total rainfall energy yield. Also, the relationship of I30 and I60 was proposed using 10-min rainfall data during 9 years.

• Smart Media Journal
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• v.5 no.4
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• pp.18-25
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• 2016

Virtualized hardware resources provides efficiency in use and easy of management. Based on the benefits, virtualization techniques are used to build large server clusters and cloud systems. The performance of a virtualized system is significantly affected by the virtual machine scheduler. However, the existing virtual machine scheduler have a problem in that the I/O response is reduced in accordance with the scheduling delay becomes longer. In this paper, we introduce the Loan/Redemption mechanism of a virtual machine scheduler in order to improve the responsiveness to I/O events. The proposed scheme gives additional credits for to virtual machines and classifies the task characteristics of each virtual machine by analyzing the credit consumption pattern. When an I/O event arrives, the scheduling priority of a virtual machine is temporally increased based on the analysis. The evaluation based on the implementation shows that the proposed scheme improves the I/O response 60% and bandwidth of virtual machines 62% compared to those of the existing virtual machine scheduler.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.60-62
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• 2003

본 연구는 DBMS에서의 Disk I/O 종류별, 옵션별 특성 및 성능 분석을 하고 이를 실제 시험을 통하여 검증하였다. Raw Device와 Quick I/O 등이 뛰어난 성능을 보여주었으나, UFS(Uxis File System)의 사용 및 관리의 용이성을 고려하여 특성에 맞는 DiskI/O 구성 방식이 필요함을 제시하였다.

• Journal of Life Science
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• v.19 no.6
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• pp.818-824
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• 2009

The mechanisms responsible for ischemia/reperfusion (I/R) injury have direct or indirect relevance to clinical lung injury after severe shock, cardiopulmonary bypass, and transplantation. This study investigated the effects of aspirin on intestinal I/R-induced acute lung injury (ALI) in rats. Lipopolysaccharide (LPS) induced cyclooxygenase-2 (COX-2) expression in A549 and RAW264.7 cells. RAW264.7 macrophages had shown greater expression of COX-2 than A549 cells. In addition, the NADPH oxidase inhibitor apocynin and p38 MAPK inhibitor SB203580 attenuated LPS-stimulated COX-2 expression. To induce ALI, intestinal ischemia was performed for 60 min prior to the 4 hr reperfusion by clamping the superior mesenteric artery in Sprague-Dawley rats. In order to test and compare the effect of non-specific COX inhibitor aspirin with the effect of mepacrine, a well known phospholipase$A_{2}$ inhibitor, rats were divided into 4 groups: Sham, I/R, Mepa+I/R (mepacrine, 60 mg/kg, i.p.), ASA+I/R (aspirin, 10 mg/kg, i.p.). In the present investigation, myeloperoxidase activities in the lung and intestinal tissues were increased by I/R. These changes were reduced by single pretreatment of mepacrine (60 mg/kg, i.p.) or aspirin (10 mg/kg, i.p.) 30 min before I/R. Structural studies demonstrated that the tissue injuries in the lung and intestine after I/R were also attenuated by the pretreatment of mepacrine or aspirin. These results suggest that I/R-induced ALI is mediated, in part, by the activation of COX. In addition, pretreatment of aspirin might be helpful for the prevention of ALI in ARDS-prone patients. In addition, the p38 MAPK inhibitor and apocynin also might be helpful to ALI through the inhibition of COX-2 expression.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.75-79
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• 2003

Oral supplementation of zinc chloride to silkworm larvae in different concentrations (30, 60 and 90 ${\mu}g$/ml) to the fourth and fifth instar resulted in a significant increase in commercial traits, like larval weight, silk gland weight, cocooning percentage in lower concentrartion (30 ${\mu}g$) treated group. The female cocoon weight, shell weight and its ratio were significantly increased in 30 and 60 ${\mu}g$ treated groups, male cocoon weight, and shell weight in 30 ${\mu}g$ treated group and its ratio in 60 and 90 ${\mu}g$ treated groups, filament length, weight and moth emergence percentage in all the treated groups and egg productivity in 90 ${\mu}g$ treated group were increased significantly. The remaining groups did not show any significant changes compared with that of carrier control.