• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.11
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• pp.44-51
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• 1995

Homogeneous, compositionally graded, and superlattice-like silicon oxynitride(SiON) dielectric layers, with the refractive index varying from 1.46 to 2.05 as a function of film thickness, were grown by computer-controlled plasma-enhanced chemical vapor deposition (PECVD) using silane, nitrogen, and nitrous oxide reactant gases. An antireflection(AR) coating and thin-film electroluminescent(TFEL) devices with multiple dielectrics were designed and fabricated using real time control of reactant gases of the PECVD system.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.677-682
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• 1998

Concrete is an inhomogeneous material consisting of larger aggregates and sand embedded in a cement paste matrix. In this study, an acoustic emission technique has been used to clarify the microscope failure mechanisms of concrete under three point bending test. AE source location has also been done to monitor the activities of internal damage and the progress of microscopic failure path during the loading. The relationship between AE characteristic and microscopic and microscopic failure mechanism is discussed.

• Journal of applied mathematics & informatics
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• v.10 no.1_2
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• pp.17-26
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• 2002

A stability analysis of a non-linear prey-predator system under the influence of one dimensional diffusion has been investigated to determine the nature of the bifurcation point of the system. The non-linear bifurcation analysis determining the steady state solution beyond the critical point enables us to determine characteristic features of the spatial inhomogeneous pattern arising out of the bifurcation of the state of the system.

• Communications of the Korean Mathematical Society
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• v.12 no.1
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• pp.177-192
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• 1997

The basic theory of the quasi-birth-and-death process is extended to a process which is inhomogeous in levels. Several key results in the standard homogeneous theory hold in a more general context than that usually stated, in particular not requiring positive recurrence. Theser results are subsumed under our development. The treatment is entirely probabilistic.

• Bulletin of the Korean Mathematical Society
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• v.51 no.4
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• pp.933-942
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• 2014

We give a representation of the component of solutions with characteristic multiplier 1 in a periodic linear inhomogeneous continuous system. It follows from this representation that asymptotic behaviors of the component of solutions to the system and to its associated homogeneous system are quite different, though they are similar in the case where the characteristic multiplier is not 1. Moreover, the representation is applicable to linear discrete systems with constant coefficients.

• Journal of the Korean Magnetic Resonance Society
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• v.7 no.2
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• pp.68-73
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• 2003

Proton magic angle spinning spectra and thermogravimetric analysis data of poly(vinyl butylal) with water in it indicate water contents in the poly(vinyl butylal) samples were reduced during magic angle spinning. Our observation implies that the centrifugal force on the samples due to magic angle spinning cannot be neglected, especially on inhomogeneous and soft samples like poly(vinyl butylal) we tested in this work.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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• pp.313-316
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• 1995

In this study, in case the lead sheath of XLPE cable (radius : 15cm, inner conductor radius : 5cm, insulation paper raidius : 6cm, dc voltage : 1MV) is harmed, so that breakdown process by inhomogeneous eletric field is simulated with Finite Element Method. The result of simulation showed that defect of lead sheath layer caused breakdown.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.347-350
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• 1996

Spectroscopic data between 7 and 15 microns obtained in 1979 by Voyager 1 and 2 Infrared Interferometer Spectrometer (IRIS) have been revisited. Using the spectral data, Jupit.er images have been constructed at the emission bands of hydrocarbons, such as methane, ethane, and acetylene. The resultant. images show differences in emission intensities in the polar regions, suggesting inhomogeneous distributions of the hydrocarbons over the auroral regions of Jupiter.

• Journal of applied mathematics & informatics
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• v.6 no.3
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• pp.809-822
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• 1999

We consider the mathematical model of a resource-based autotroph-herbivore system where diffusion of nutrient within the soil is taken into account. We have derived the conditions for the existence of steady-state to the system and studied the stability and instability of the patially homogeneous case. Then we have introduced the diffusion term to the system and studied the qualitative behabviour of the spatially inhomogeneous case. Finally we have discussed the salient features of the analytical results giving also the ecological interpretations.

• Journal of applied mathematics & informatics
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• v.5 no.2
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• pp.403-426
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• 1998

We present an algorithm to find an approximation for the stationary distribution for the general ergodic spatially-inhomogeneous block-partitioned upper Hessenberg form. Our approximation makes use of an associated upper block-Hessenberg matrix which is spa-tially homogeneous except for a finite number of blocks. We treat the MAP/G/1 retrial queue and the retrial queue with two types of customer as specific instances and give some numerical examples. The numerical results suggest that our method is superior to the ordinary finite-truncation method.