• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.3
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• pp.173-180
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• 2007

In this paper, we have proposed a simple finite element model for separation mode analysis on the roadwheel and track assembly of main battle tank and established a contact stress-based mechanism which could explain the initiation and growth of separation defect occurred during the test of padreplacable track. It was proved that the longitudinal contact shear stress component on the pin hole region of the track shoe body which is parallel to the driving direction is consistent with the crack initiation at the bonding surface between track shoe and wheel-side rubber. The longitudinal shear stress increased locally near the separated region after the separation initiated. So we could assume that the local stress concentration accelerates the separation growth according to the shear mode.

• 한국전산유체공학회:학술대회논문집
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• 2009.04a
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• pp.43-50
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• 2009

In order to reduce the download around Smart UAV(SUAV) at hovering and transition mode, flow control using synthetic jet has been performed. Many of the complex tilt rotor flow features are captured including wing leading and trailing edge separation, and the large region of separated flow beneath the wing. First, in order to control the trailing edge separation, synthetic jet is located at 30, 95% of flap chord length. The flow control using synthetic jet on flap shows that stall characteristics depending on several mode can be improved through separation vortices resizing. Also, a flap jet and a 0.01c jet which control the separation efficiently are applied at the same time at each test case because controlling the leading edge separation is essential for download reduction. As a result, time averaged download is reduced about 18% comparing with no control case at hovering mode and 48% at transition mode. These research results show that if flow control using leading edge jet and trailing edge jet is used effectively to the SUAV in overall flight mode, flight performance and stability can be improved.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.4
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• pp.324-331
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• 2014

The sensor configuration of the magnetostrictive guided wave system can be described as a single continuous transducing element which makes it difficult to separate the individual modes from the reflected signal. In this work we develop the mode decomposition technique employing chirplet transform based on the maximum likelihood estimation, which is able to separate the individual modes from dispersive and multimodal waveform measured with the magnetostrictive sensor, and estimate the time-frequency centers and individual energies of the reflection, which would be used to locate and characterize defects. Simulation results on a carbon steel pipe are presented, which show the accurate mode separation and more discernible time-frequency representation could become enabled using the proposed technique.

• Nuclear Engineering and Technology
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• v.29 no.5
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• pp.399-405
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• 1997

In this study a new phase separated spectral analysis algorithm is proposed to identify CSB vibration mode directly from ex-core neutron signals. Ex-core neutron signals can be decomposed into the global, core support barrel (CSB) beam mode, and CSB shell mode components by the new phase separation algorithm based on the characteristics of Fourier transform. By using the proposed algorithm and the conventional spectral analysis the vibration mode of the CSB and the fuel assembly of Ulchin-1 NPP were identified from measured ex-core neutron signals.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.1050-1053
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• 2003

Polymer dispersed liquid crystal mode can be classified into two cases, normally scattering mode (NS) and normally transparent (NT) mode according to an initial state. Electro-optic characteristic NS/NT PDLC mode can be improved by controlling the factors to influence the phase separation. In case of NS PDLC mode, we inspected change of a phase separation as a function of curing temperature for the mixture of E7 and NOA65 with different ratios. When the LC concentration is less than polymer such as LC : NOA65 = 40 : 60wt%, the PDLC cell is influenced strongly by the curing temperature. However, when LC concentration is much less than polymer such as LC : NOA65 : 80 : 20wt%, it is influenced slightly by the curing temperature. In case of NT PDLC mode, we observed change of a phase separation as a function of the ratio of the mixture and UV conditions such as curing temperature, UV intensity The cell made with strong UV intensity and curing temperature of $20^{\circ}C$, in case that the ratio of LC to polymer is 70:30wt%, showed good electro-optic characteristics.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.214.3-214.3
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• 2003

The chiral separation of multiple ${\beta}$-blockers is described for their accurate chiral discrimination by chiral capillary electrophoresis (CE). The cyc1odextrin-modified CE system was operated in the reversed polarity mode. In this mode, fairly good enantiomeric resolutions were achieved. Relative migration times to internal standard under optimum conditions were characteristic of each enantiomer with good precision. Therefore, in this study, the usefulness for the chiral separation and accurate identification will be discussed.

• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.694-699
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• 1997

Normal-phase HPLC was used to separate the useful phospholipids, PE, PI and PC in soybean lecithin. The mobile phase used in this experiments were haxane, isopropanol and methanol, the gradient mode was applied as the three components could not be separated by the isocratic mode. To find the optimum separation condition, the concentration profiles of effluents were calculated from the plate theory and the capacity factor in step-gradient mode. From the calculated results, PE was separated with hexane/isopropanol/methanol = 90/5/5vol.% in isocratic mode and PI and PC were resolved in the conditions of 10min gradient time and the second mobile phase of hexane/isopropanol/methanol=50/20/30vol.% in step-gradient mode. The agreement between the calculated concentration profile and experimental data was good, so the methodology developed in this work can be used to obtain the optimum separation condition in gradient mode.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.2211-2217
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• 2016

The Locator/Identifier Separation Protocol (LISP) is a new routing architecture that implements a new semantic for IP addressing. It enables the separation of IP addresses into two new numbering spaces: Endpoint Identifiers (EIDs) and Routing Locators (RLOCs). This approach will solve the issue of rapid growth of the Internet's DFZ (default-free zone). In this paper, we propose an algorithm called the Propagated-Mode Mapping System to improve the map request process of LISP-DDT.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.973-975
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• 1998

For a nonlinear feedback linearization-full order observer/sliding mode controller (NFL-FOO/SMC), the separation principle is derived, and the closed-loop stability is proved by a Lyapunov function candidate using an addition form of the sliding surface vector and the estimation error.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.979-981
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• 1998

This paper presents a stability proof for the nonlinear feedback linearization-observer/sliding mode model following controller (NFL-O/SMMFC). The separation principle is derived, and the closed-loop stability is proved by a Lyapunov function candidate using an addition form of the sliding surface vector and the estimation error.