• Journal of the Korean Ceramic Society
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• v.38 no.10
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• pp.914-920
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• 2001

The grain orientation distribution and grain boundary characterization of $ZrB_2$-ZrC composites sintered by a SPS(Spark Plasma Sintering) method, a new sintering technique were analyzed by the EBSP technique and then their crystallographic results have been compared with those of a sintered specimen using a PLS(Pressureless Sintering) method. In the $ZrB_2$-ZrC composite manufactured by SPS, (0001) planes of $ZrB_2$ were oriented in the direction normal to the specimen surface. In the case of PLS, those of $ZrB_2$ were oriented normal to the electron beam. In both cases of PLS and SPS, ZrC grains had the randomly oriented grain structure. The grain boundary characterization showed that low angle grain boundaries in the PLS and SPS processed materials constituted about 10% and 8% of the total number of boundaries, respectively, represented the only slight difference between the proportion of low angle grain boundary. However, in the distribution of CSL(Coincident Site Lattice) boundaries, it was shown the higher proportion of CSL boundaries with $\Sigma$ 3,5,7,9, 11 in the SPS processed material.

• Proceedings of the Acoustical Society of Korea Conference
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• 1993.06a
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• pp.17-20
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• 1993

The acoustic mode of a perforated tube muffler was investigated both theoretically and experimentally to explain the cavity-tones induced by through-flow. The cutoff frequencies for the axisymmetric modes were obtained and confirmed experimentally. It was found that the cutoff frequencies are decreased significantly by the perforated tube. The onset frequencies of the cavity-tones were compared with the cutoff frequencies of the acoustic mode and it was found that the cavity-tones are induced by the radial acoustic modes and their frequency stages are coincident with the discrete cutoff frequencies.

• Nuclear Engineering and Technology
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• v.11 no.2
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• pp.133-136
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• 1979

In the paper it is proposed to use Ge(Li) detectors in determining fast neutron spectra. The spectrum at 691.4 KeV which is produced by the internal conversion of Ge nuclei being broadened by the coincident ionization energy deposited by recoil Ge atoms is proposed to be analysed in estimating the fast neutron spectra.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.486-489
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• 2004

In this paper, we try to detect the peel out effect and find the strain difference between the main structure and retrofitting patch material when they separate from each other. In the experiment, two fiber optic Bragg grating sensors are applied to the main concrete structure and the patching material separately at the same position. The sensors show coincident behaviors at the initial loading, but different behaviors after a certain load. The test results show the possibility of optical fiber sensor monitoring of beam structures retrofitted by the composite patches.

• Journal of the Korean Magnetic Resonance Society
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• v.11 no.1
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• pp.1-9
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• 2007

An unequal site exchanging system induced by restricted rotation of 9-methyl group in 1,8-dichloro-9-triptycene has been studied by spin-lattice relaxation and 2D-EXSY experiments. The exchange rate obtained from relaxation studies is very well coincident to the result of line shape analysis, and the difference of the relaxation times ($T_1$) in two different sites has an important role to analyze 2D-EXSY experimental data.

• Journal of Biosystems Engineering
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• v.26 no.6
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• pp.503-508
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• 2001

In this paper, time-fiequency analysis and multi-dimensional spectral analysis methods are applied for source identification and diagnosis of non-stationary sound/vibration signals. Sound or vibration problems of general vehicle and agricultural machinary are under 500 Hz. So We used linearly increased chirp signals under 500 Hz. By checking the coherences on concerned time, fur time-variant non-stationary signals, this simulation it very well coincident to expected results.

• Bulletin of the Korean Mathematical Society
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• v.42 no.4
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• pp.703-711
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• 2005

Using the belongs to relation ($\in$) and quasi-coincidence with relation (q) between fuzzy points and fuzzy sets, the concept of (${\alpha},\;{\beta}$)-fuzzy subalgebras where ${\alpha},\;{\beta}$ are any two of $\{\in,\;q,\;{\in}\;{\vee}\;q,\;{\in}\;{\wedge}\;q\}$ with $\;{\alpha}\;{\neq}\;{\in}\;{\wedge}\;q$ is introduced, and related properties are investigated.

• Bulletin of the Korean Mathematical Society
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• v.45 no.1
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• pp.191-205
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• 2008

In this paper, we construct the analytic solutions and numerical solutions for a two-dimensional Riemann problem for Burgers' equation. In order to construct the analytic solution, we use the characteristic analysis with the shock and rarefaction base points. We apply the composite scheme suggested by Liska and Wendroff to compute numerical solutions. The result is coincident with our analytic solution. This demonstrates that the composite scheme works pretty well for Burgers' equation despite of its simplicity.

• Honam Mathematical Journal
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• v.21 no.1
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• pp.75-95
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• 1999

Dimensions of irreducible $so_5(F)$-modules over an algebraically closed field F of characteristics p > 2 shall be obtained. It turns out that they should be coincident with $p^{m}$, where 2m is the dimension of coadjoint orbits of ${\chi}{\in}so_5(F)^*{\backslash}0$ as Premet asserted. But there is no subregular point for $g=sp_4(F)=so_5(F)$ over F.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.45-48
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• 1996

Rings are common in disk galaxies. These rings are either indistinguishable from a pair of tightly wound spirals, or themselves are a part of the spiral structure. Furthermore, their occurrence is seen coincident with a bar in the center. In this paper, we interpret this spiral-ring structure as density waves resonantly excited by a rotating bar potential. The theory gives excellent agreement for the molecular spiral-rings in central parts. of nearby disk galaxies, observed by high resolution radio arrays. The same mechanism works for more distant spiral-rings in the outer parts of disk galaxies qualitatively, although the problem is complicated by the coupling of the stellar and gaseous disks.