• Applied Chemistry for Engineering
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• v.8 no.3
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• pp.382-388
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• 1997

Reforming of propane by carbon dioxide using NiO/${\gamma}$-$A1_2O_3$ was carried out in a pulse or continuous kid bed reactor. NiO/${\gamma}$-$Al_2O_3$ showed higher dissociation ability of $CO_2$ than NiO/${\gamma}$-$Al_2O_3$, and the former exhibited higher conversion of propane than the latter. The presence of oxygen in the reaction mixture of propane and $CO_2$ increased the conversion of propane and reduced the amount of carbon deposit on the catalyst surface. Mechanical mixture catalyst of NiO/${\gamma}$-$Al_2O_3$ and $Ga_2O_3$ showed higher stability to deactivation than NiO/${\gamma}$-$Al_2O_3$ itself. The synergistic effect between NiO/${\gamma}$-$Al_2O_3$ and $Al_2O_3$ was also observed in this study.

• Proceedings of the Korean Society of Computer Information Conference
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• 2019.07a
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• pp.313-314
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• 2019

본 논문에서는 특징점 검출 알고리즘을 적용하여 ultrasound image에서 특징점을 검출하는 것과 object dectection을 위한 keypoints가 object에 올바르게 위치하는지를 검증하는 실험을 진행한다. 특징점 검출을 위한 알고리즘으로는 Scale Invariant Feature Transform(SIFT)과 Harris corner detection 을 적용하여 검증한다.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.53-59
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• 1996

This study was conducted to evaluate the effects of fowl dzopping. saw dust and rice hall on the soil microflora in vitro. The experiment was designed in seven treatments with the various organic materials and they were only soil (control). soil + fowl dropping (S+F), soil+fowl dropping+rice hull (S+F+R) soil+fowl dropping*saw dust (S+F+S). soil+chemical fertilizer (S+C.F), fowl dropping+rice hull (F+R) and fowl dropping+saw dust (F+S). All the samples of treatment were incubated in $28{\pm}2^{\circ}C$ condition and tested the activity of soil microflora for 84 days The activity of fungi, total bacteria, gram-negative bacteria and actinomycetes showed the highest values at, twenty-first day and the spore-forming bacteria was at forty-second day after incubation. The number of fungi and gram-negative bacteria showed the highest values in the treatment of F+S, the spore-forming bacteria and the actinomycetes were in the S+F+S. and the number of total bacteria was in the F+C.F., but in the treatment of F+R. all the microorganism except fungi showed the lowest values in their numbers. The composition ratio of dead bacteria was higher in the treatments of S+F+R and F+R than in those of others as 70% and 40% respectively. Actinomycetes isolated from the treatments of S+F and S+F+S were identified as Streptomyces sp.. Nocardia sp., Micromonospora sp. Actinomadura sp. and Saccharomonospora sp.

• Applied Chemistry for Engineering
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• v.8 no.3
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• pp.374-381
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• 1997

Ceramic membranes are prepared by using molding method of the glass materials, ceramic-silicone composite membranes are synthesized with immersing silicone compound of sodiumate, $S_3$-Al, S3and we investigated the properties of gas permeation. Ceramic membranes and ceramic-sodiumate membranes that has been prepared were identified as porous structure and ceramic-$S_3$-Al membranes and ceramic-$S_3$ membranes were showed with dense structure by immersion of silicone compounds. Gas permeation properties through the ceramic membranes and ceramic-sodiumate membranes decreased with increasing temperature and linearly increased with increasing pressure, ceramic-$S_3$-Al membranes and ceramic-$S_3$ membranes increased with increasing temperature and pressure effect was low. Permeation rate was found out high value with ceramic membranes and in order of ceramic-sodiumate membranes, ceramic-$S_3$-Al membranes and ceramic-$S_3$ membranes, but selectivity reversed in the order. Gas permeation mechanism through the ceramic membranes and ceramics-sodiumate composite membrane decreased with increasing temperature, suggesting an Knudsen diffusion mechanism, but ceramic-$S_3$-Al composite membranes and ceramic-$S_3$ composite membranes showed an activated diffusion by which gas permeation rates through the membranes increased with an increase in temperature.

• Journal for History of Mathematics
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• v.32 no.1
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• pp.1-15
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• 2019

We divide the timeline of the history of Finsler geometry, which dates back to Riemann's inaugural lecture in 1854, into three periods (hibernation, hiatus, rebirth) and we study formation of Romanian Finsler school around Iasi, Romania during the hiatus period. We look for the history centered around Radu Miron who is a third generation geometer of Iasi University and the mathematical heritage there through five generations. We also investigate mathematical impact of T. Levi-Civita, D. Hilbert, ${\acute{E}}$ Cartan who are considered as top mathematicians at their time.

• Communications of the Korean Mathematical Society
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• v.9 no.3
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• pp.641-648
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• 1994

Let M be a minimally immersed closed hypersurface in $S^{n+1}$, II the second fundamental form and $S = \Vert II \Vert^2$. It is well known that if $0 \leq S \leq n$, then $S \equiv 0$ or $S \equiv n$ and totally geodesic hypersheres and Clifford tori are the only possible minimal hypersurfaces with $S \equiv 0$ or $S \equiv n$ ([6], [2]). From these results, Chern suggested some questions on the study of compact minimal hypersurfaces on the sphere with S =constant: what are the next possible values of S to n, and does in the ambient sphere\ulcorner By the way, S is defined extrinsically but, in fact, it is an intrinsic invariant for the minimal hypersurface, i.e., S = n(n-1) - R, where R is the scalar, curvature of M. Some partial answers have been obtained for dim M = 3: Assuming $M^3 \subset S^4$ is closed and minimal with S =constant, de Almeida and Brito [1] proved that if $R \geq 0$ (or equivalently $S \leq 6$), then S = 0, 3 or 6, Peng and Terng ([5]) proved that if M has 3 distint principal curvatures, then S = 6, and in [3] Chang showed that if there exists a point which has two distinct principal curvatures, then S = 3. Hence the problem for dim M = 3 is completely done. For higher dimensional cases, not much has been known and these problems seem to be very hard without imposing some more conditions on M.

• Honam Mathematical Journal
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• v.29 no.4
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• pp.695-700
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• 2007

We establish two uniqueness theorems for non-constant entire functions which extends results of J. S. Hwang in J. Math. Anal. and its Appl. Vol. 37 (1972) 452-456.

• Communications of the Korean Mathematical Society
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• v.17 no.3
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• pp.505-517
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• 2002

We introduce certain conformally invariant h-Finsler connection in a Rizza manifold. Using this connection, we find some conformally invariant Finsler tensors. The conformal flatness and the Kaehlerian Finsler manifold with respect to the above connection are investigated.

• Proceedings of the Korean Society of Computer Information Conference
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• 2019.07a
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• pp.89-90
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• 2019

본 논문에서는 ultrasound image Right Parasagittal Liver에 edge detection을 적용한 후, 특징점 검출 알고리즘인 Scale Invarient Feature Transfom(SIFT)를 이용하여 특징점의 위치를 살펴보도록 한다. edge detection 알고리즘으로는 Canny edge detection과 Prewitt edge detection을 적용하기로 한다.

• Applied Microscopy
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• v.35 no.4
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• pp.64-73
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• 2005

In this paper we discussed in details how to determine the nature of dislocations in a crystal such as a Burgers vector, the line vector of dislocation and the associated slip plane, using LACBED and usual imaging techniques. These techniques basically involve the application of Cherns and Prestone s rules, the simulations of LACBED patterns with a certain form of the dynamical diffraction theory. The theoretical aspects including necessary approximations for calculations also were in details discussed. As a test specimen for experiments, the foils of a pure aluminum, containing many dislocations with appropriate density for LACBED experiments, were used..