• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.508-509
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• 2006

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.512-513
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• 2006

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1040-1047
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• 2008

Hypoid gears are widely used in rear drive and 4WD vehicle axles. Investigation of their sensitivity to deflections is one of the most important aspects of their design and optimization procedures. The deflection test is performed in the actual gear mounting using completely processed gear. This test should cover the full operating range of gear loads from no load to peak load. Under peak load the contact pattern should extend to the tooth boundaries without showing a concentration of the contact pattern at any point on the tooth surface. Transmission error is tested on an axle assembly triaxial real car load condition.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.6
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• pp.862-875
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• 1996

The CTD data observed in the sea northwest of Cheju Island have been analyzed to figure out the seasonal circulation around Cheju Island. Warm and saline waters flow into the Yellow Sea through the middle region of the Yellow Sea in winter and along the west coast of Korean Peninsula in summer. On the other hand, cold and less saline waters flow out of the Yellow Sea through the middle region in summer and along the west coast of Korean Peninsula in winter. These flows make the seasonal circulation around Cheju Island. As dynamics, the monsoon wind and the variation of Kuroshio transport have been suggested. Comparing the observational result, the circulation driven by the variation of Kuroshio transport is strengthened by monsoon winds in the numerical model.

• Proceedings of the KIEE Conference
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• 1997.07c
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• pp.1112-1114
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• 1997

When reliability is estimated to be insufficient, a planner must take action to improve them. So, the measures for improving reliability are mainly considered in the planning process. In order to provide quantitative information concerning reliability evaluation, this paper-describes an algorithm to find reserve margin in power system planning. The IEEE Reliability Test System(RTS) is used to demonstrate the effectiveness of the proposed algorithm.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1892-1896
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• 2008

Inverter-fed induction motors (IFM) are prevalent in traction vehicles. However, the winding insulation of IFM is substantially more stressed than of line-powered motors by surge voltages. Consequently, the winding insulation of IFM should be estimated by surge voltages. Also, the weakness of coil insulation can be detected by the surge voltage test. This paper described the insulation evaluation of induction motors by application of surge voltages. A surge voltage generator with the maximum voltage of 5 kV and the selectable rise-time in ranges of $50\;ns\;{\sim}\;500\;ns$ was fabricated. In the experiment, we applied surge voltages into induction motors with the magnitude and the risetime according to IEEE 522. By the analysis of applied surge voltage and current waveforms, we could find difference between normal and defection windings.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1977-1983
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• 2009

This paper described partial discharge(PD) patterns depending on types of insulation defects in CNCO-W cable(Concentric Neutral Closs-linked Polyethylene Insulated Polyolefin-Water Proof Sheathed Power Cable). The PD measurement system consists of a coupling network, a detection impedance, and a low noise amplifier. A 16 bit, 250 MS/s data acquisition system was used to analyze PD patterns. To simulate insulation defects in a power cable, a needle with the curvature radius of $10{\mu}m$ was inserted into the insulation part. We measured phase ($\Phi$), magnitude (q), and counts (n) of PD pulse for the defects, and classified PD patterns using the PRPD (phase Resolved Partial Discharge) method. From the analysis of acquired PD signals, we could find that a unique PD pattern is formed according to the types of defect.

• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.513-515
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• 1995

Based on the concept of Load Supplying Capability of a transmission network, we provides an information concerning network adequacy. In particular this paper describes an algorithm regarding load supplying margin of transmission networks. And a different growth rate is assigned to each load point so that various demand characteristics can be taken into consideration at respective locations. In addition to this, in this paper, both generation and transmission equipment will be considered in determining the system capability. A 10 bus model system is used to demonstrate the capability of the proposed algorithm.

• YAKHAK HOEJI
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• v.54 no.5
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• pp.416-421
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• 2010

We examined whether indomethacin, noscapine, coumarin, uridine and betaine affect airway mucin production induced by EGF or TNF-${\alpha}$ from NCI-H292 cells. Cells were pretreated with each agent for 30 min and then stimulated with EGF or TNF-${\alpha}$ for 24 h. Of the five compounds, coumarin suppressed airway mucin production induced by EGF or TNF-${\alpha}$. However, indomethacin suppressed airway mucin production induced by EGF. This result suggests that coumarin and indomethacin can regulate the production of mucin induced by EGF, by directly acting on airway epithelial cells.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.165-168
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• 2004

Due to the demolition of old structures, primarily buildings, an amount of discharged construction wastes are increased. From the construction wastes, recycled aggregate can be used as a useful resource for concrete. However, its application to structural member is very limited. In this experimental study, the compressive strength of spun-concrete using recycled aggregate was investigated. Coarse aggregate was replaced with $100\%$ of the recycled coarse aggregate, and recycled fine aggregate was replaced with various amount. According to the test results, the specimen of spun-concrete showed uniform compressive strength regardless the amount of replaced recycled fine aggregate.