• Journal of the Korean Mathematical Society
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• v.45 no.5
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• pp.1361-1378
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• 2008

This paper deals with the study of dichotomy and conditioning for two-point boundary value problems associated with first order matrix Lyapunov systems, with the help of Kronecker product of matrices. Further, we obtain close relationship between the stability bounds of the problem on one hand, and the growth behaviour of the fundamental matrix solution on the other hand.

• Journal of applied mathematics & informatics
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• v.12 no.1_2
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• pp.165-182
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• 2003

Toeplitz matrix method and the product Nystrom method are described for mixed Fredholm-Volterra singular integral equation of the second kind with Carleman Kernel and logarithmic kernel. The results are compared with the exact solution of the integral equation. The error of each method is calculated.

• Journal of applied mathematics & informatics
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• v.16 no.1_2
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• pp.453-459
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• 2004

A left-invariant flat Riemannian connection on a Lie group makes its Lie algebra a left symmetric algebra compatible with an inner product. The left symmetric algebra is decomposed into trivial ideal and a subalgebra of e(l). Using this result, the Lie group is embedded isomorphically into the direct product of O(l) $\times$ $R^{k}$ for some nonnegative integers l and k.

• Journal of applied mathematics & informatics
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• v.24 no.1_2
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• pp.541-545
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• 2007

In this paper, we study the infinitesimal transformation on the fibred Riemannian space. The conharmonic curvature tensor is invariant under the conharmonic transformation. We have proved that the conharmonically flat fibred Riemannian space with totally geodesic fibre is locally the Riemannian product of the base space and a fibre.

• Journal of applied mathematics & informatics
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• v.27 no.3_4
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• pp.673-683
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• 2009

We point out: to make Hermtian matrices A and B satisfy Styan matrix inequality, the condition "positive definite property" demanded in the present literatures is not necessary. Furthermore, on the premise of abandoning positive definite property, we derive Styan matrix inequality of Hadamard product for inverse Hermitian matrices and the sufficient and necessary conditions that the equation holds in our paper.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1999.04a
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• pp.5-8
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• 1999

여성의 breast cancer의 1/3 의 경우가 hormone-dependent에 의한 것이다. 따라서 그 치료의 접근 방법으로써 estrogen receptor에 작용하거나, receptor-mediated gene trenscription을 저해하는 antiestrogen을 사용하는 것이 있다. Estrogen은 microsomal cytochrome P-450 enzyme complex system에 의해 androgen으로부터 생합성되는 hormone이며, estrogen product는 steroid product의 biosynthetic sequence의 마지막 단계에서 생산되고, aromatase는 이에 관여하는 enzyme으로써, aromatase를 선택적으로 저해하는 경우에 다른 steroid의 생산에 영향을 미치지 않고 estrogen 생산을 감소 시킬 수 있다. 이러한 관점에서, aromatase를 선택적으로 저해하는 것은 hormone-dependent breast cancer를 완화시킬 수 있는 가능성을 가진 cancer chernopreventive agents의 새로운 방법이라 할 수 있다.

• Journal of applied mathematics & informatics
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• v.40 no.1_2
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• pp.173-184
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• 2022

We investigated the invariant subspaces of the fractional integral operator in the Sobolev space W^k_p[0, 1] and prove unicellularity of the operator J^α by using the Duhamel product.

• Journal of applied mathematics & informatics
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• v.41 no.1
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• pp.123-132
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• 2023

We define an operator version of the relative Rényi entropy as the generalization of relative von Neumann entropy, and provide its fundamental properties and the bounds for its trace value. Moreover, we see an effect of the relative Rényi entropy under tensor product, and show the sub-additivity for density matrices.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.1
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• pp.1-9
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• 2012

It is well known that internet shoppers are very sensitive to sale prices. They visit the various shopping malls and collect the product information including purchase conditions for goods purchase decision-making. Recently the necessity of information support is increasing because of increase of information amount which is necessary and complexity of goods purchase decision-making process. The comparison shopping agent systems have provided price comparison information which is collected from various shopping malls to satisfy internet shoppers information craving. But the frequent price change caused by keen price competition is becoming the primary reason of information quality decline among price comparison sites. RSS which is a family of web feed formats used to publish frequently updated is applied even in on-line shopping malls. This paper develops a RSS product information collection system to get real-time product information. The proposed product information system consists of (1) web crawler module for searching RSS feed shopping malls automatically, (2) RSS reader module for parsing product information from RSS feed file, (3) product DB and (4) product searching module. Performance of the proposed system is higher than the comparison shopping agent systems when it is defined with the volume of collecting product information per unit time.

• Journal of Environmental Science International
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• v.26 no.5
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• pp.651-659
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• 2017

This study aimed to estimate the effects of replacing Mushroom By-Product (MBP) with Tofu By-Product (TBP) on the chemical composition, microbes, and rumen fermentation indices of Fermented Diets (FDs). The basal diet was formulated using MBP, TBP, rice bran, molasses, and inoculants. The MBP in the basal diet was replaced with TBP at 0, 5, and 10% on Dry Matter (DM) basis for the experimental diets. The experimental diets were fermented at $39^{\circ}C$ for 144 h. Chemical composition, pH, microbes, and rumen fermentation indices of the FDs were analyzed. With increasing TBP replacement, crude protein content of FDs increased (L, P < 0.001), whereas crude ash content decreased (L, P = 0.002). Lactic acid bacteria and Bacillus subtilis contents in the TBP-replaced FDs were higher than those in the control (P < 0.05), whereas pH level and mold count were lower (P < 0.05). With increasing TBP replacement, in vitro rumen digestibility of DM (L, P = 0.053) and neutral detergent fiber (L, P = 0.024) increased, wheres rumen pH changed (P = 0.026) quadratically. Rumen total volatile fatty acid (L, P = 0.001) and iso-butyrate contents (Q, P = 0.003) increased with increasing TBP replacement. In conclusion, this study indicates that the replacement of MBP with TBP could improve the quality of FD.