• Journal of the Korean Vacuum Society
• /
• v.12 no.S1
• /
• pp.63-66
• /
• 2003

It is experimentally shown that a $TiO_2$ film on Si(111) substrate was prepared by using the technique of D.C. reaction sputter deposition with $Ar^{+}$ ion beam bombardment, and a layer-like structure was observed from the depth profile of the interface between $TiO_2$ film and Si substrate with Scanning Electron Microscopy and Electron Probe. It was also surprisingly discovered that Ti atoms could be detected at about 9 $\mu$m depth. The $TiO_2$-Si interface bombarded by $Ar^{+}$ ion beams revealed multi-layer structures, a mechanism might be caused by defect diffusion, impurity and matrix relocation. Multi-relocations of impurity and matrix atoms were as a result of profile broadening of the $TiO_2$-Si interface, and the spread due to matrix relocation in this system is shown to exceed much more the spread due to impurity relocation.

• Journal of Korean Society of Transportation
• /
• v.22 no.1 s.72
• /
• pp.43-62
• /
• 2004

Conventionally the estimation method of the origin-destination Matrix has been developed by implementing the expansion of sampled data obtained from roadside interview and household travel survey. In the survey process, the bigger the sample size is, the higher the level of limitation, due to taking time for an error test for a cost and a time. Estimating the O-D matrix from observed traffic count data has been applied as methods of over-coming this limitation, and a gradient model is known as one of the most popular techniques. However, in case of the gradient model, although it may be capable of minimizing the error between the observed and estimated traffic volumes, a prior O-D matrix structure cannot maintained exactly. That is to say, unwanted changes may be occurred. For this reason, this study adopts a conjugate gradient algorithm to take into account two factors: estimation of the O-D matrix from the conjugate gradient algorithm while reflecting the prior O-D matrix structure maintained. This development of the O-D matrix estimation model is to minimize the error between observed and estimated traffic volumes. This study validates the model using the simple network, and then applies it to a large scale network. There are several findings through the tests. First, as the consequence of consistency, it is apparent that the upper level of this model plays a key role by the internal relationship with lower level. Secondly, as the respect of estimation precision, the estimation error is lied within the tolerance interval. Furthermore, the structure of the estimated O-D matrix has not changed too much, and even still has conserved some attributes.

• Journal of Korean Society of Transportation
• /
• v.14 no.3
• /
• pp.7-26
• /
• 1996

The estimation of real-time Origin-Destination(O-D) parameters, which gives travel demand between combinations of origin and destination points on a urban freeway network, from on-line surveillance traffic data is essential in developing an efficient ATMS strategy. On this need a real-time O-D parameter estimation model is formulated as a parameter adaptive filtering model based on the extended Kalman Filter. A Monte Carlo test have shown that the estimation of time-varying O-D parameter is possible using only traffic counts. Tests with field data produced the interesting finding that off-ramp volume predictions generated using a constant freeway O-D matrix was replaced by real-time estimates generated using the parameter adaptive filter.

• Journal of the Korean Mathematical Society
• /
• v.51 no.4
• /
• pp.655-663
• /
• 2014

Let R be a ring with identity, X(R) the set of all nonzero, non-units of R and G(R) the group of all units of R. We show that for a matrix ring $M_n(D)$, $n{\geq}2$, if a, b are singular matrices of the same rank, then ${\mid}o_{\ell}(a){\mid}={\mid}o_{\ell}(b){\mid}$, where $o_{\ell}(a)$ and $o_{\ell}(b)$ are the orbits of a and b, respectively, under the left regular action. We also show that for a semisimple Artinian ring R such that $X(R){\neq}{\emptyset}$, $$R{{\sim_=}}{\oplus}^m_{i=1}M_n_i(D_i)$$, with $D_i$ infinite division rings of the same cardinalities or R is isomorphic to the ring of $2{\times}2$ matrices over a finite field if and only if ${\mid}o_{\ell}(x){\mid}={\mid}o_{\ell}(y){\mid}$ for all $x,y{\in}X(R)$.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.11
• /
• pp.2512-2520
• /
• 1997

The classes of Reverse Jacket matrix [RJ]$_{N}$ and the corresponding Restclass Reverse Jacket matrix ([RRJ]$_{N}$) are defined;the main property of [RJ]$_{N}$ is that the inverse matrices of them can be obtained very easily and have a special structure. [RJ]$_{N}$ is derived from the weighted hadamard Transform corresponding to hadamard matrix [H]$_{N}$ and a basic symmertric matrix D. the classes of [RJ]$_{2}$ can be used as a generalize Quincunx subsampling matrix and serveral polygonal subsampling matrices. In this paper, we will present in particular the systematical block-wise extending-method for {RJ]$_{N}$. We have deduced a new orthorgonal matrix $M_{1}$.mem.[RRJ]$_{N}$ from a nonorthogonal matrix $M_{O}$.mem.[RJ]$_{N}$. These matrices can be used to develop efficient algorithms in IMT2000 signal processing, multidimensional subsampling, spectrum analyzers, and signal screamblers, as well as in speech and image signal processing.gnal processing.g.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.18 no.6
• /
• pp.1602-1607
• /
• 2004

3-O-D-galactopyranosylglyceride (GPG; fatty acids R1, R2 = myristic acid 11.62%, palmitic acid 61.90% and oleic acid 26.48%) was isolated from Chrysanthemum coronarium L that has been used for treating renal and cardiovascular diseases as one of vegetables or medicinal drug. However, little was known about the anti-angiogenic activity of GPG. Thus, anti-angiogenic effect of GPG was evaluated in human umbilical vein endothelial cells (HUVECs) in vitro and in vivo. GPG effectively inhibited bFGF-induced migration and invasion of HUVECs in a concentration-dependent manner, whereas it did not inhibit bFGF-induced proliferation and capillary-like tube formation of HUVECs. To examine the mechanism of anti-angiogenic activity of GPG, gelatin zymography was carried out. GPG downregulated the expression of matrix metalloproteinase-2 in a concentration-dependent manner. Furthermore, GPG significantly disrupted bFGF-induced neovascularization on the chick chorioallantoic membrane assay in vivo. These results suggest that 3-O--D-galactopyranosylglyceride may inhibit neovascularization by inhibiting angiogenic activity of endothelial cells via regulation of matrix metalloproteinase-2 (MMP-2).

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.192.2-192.2
• /
• 2003

Apigenin-7-O-${\beta}$-D-glucoside, chrysoeriol, and luteolin were isolated from the aqueous ethanolic extract of Zostera marina L. leaves as the scavengers of reactive oxygen species (ROS) with the SC$\_$50/ values of 0.18 mM, 0.68 mM, and 0.18 mM against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 0.04 mM, 0.03 mM, and 0.01 mM against superoxide radicals in the xanthine/xanthine oxidase system, respectively. The luteolin suppressed the expression of matrix metalloproteinase-1 (MMP-1) up to 44% at 4.0 ${\mu}$M. (omitted)

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.886-889
• /
• 2004

A simple macro triangle with drilling d.o.f.'s is proposed for plane stress problems based on IET(Individual element test) and finite element template. Three-node triangular element has geometrical advantages in preprocessing but suffers from bad performance comparing to other shapes of elements -especially quadrilateral. Main purpose of this study is to construct a high-performance linear triangular element with limited supplementary d.o.f.'s. A triangle is divided by three sub-triangles with drilling d.o.f.'s. The sub-triangle stiffness come from IET passing force-lumping matrix, so this assures the consistency of the element. The macro element strategy takes care of the element‘s stability and accuracy like higher-order stiffness in the F.E. template. The resulting element fits on the uses of conventional three-node. Benchmark examples show proposed element in closed form stiffness from CAS (Computer algebra system) gives the improved results without more computational efforts than others.

• Journal of the Chungcheong Mathematical Society
• /
• v.10 no.1
• /
• pp.127-139
• /
• 1997

The spherical non-commutative $\mathbb{S}_{\omega}$ were defined in [2,3]. Assume that no non-trivial matrix algebra can be factored out of the $\mathbb{S}_{\omega}$, and that the fibres are isomorphic to the tensor product of a completely irrational non-commutative torus with a matrix algebra $M_k(\mathbb{C})$. It is shown that the tensor product of the spherical non-commutative torus $\mathbb{S}_{\omega}$ with the even Cuntz algebra $\mathcal{O}_{2d}$ has a trivial bundle structure if and only if k and 2d - 1 are relatively prime, and that the tensor product of the spherical non-commutative torus $S_{\omega}$ with the generalized Cuntz algebra $\mathcal{O}_{\infty}$ has a non-trivial bundle structure when k > 1.

• Journal of the Chungcheong Mathematical Society
• /
• v.11 no.1
• /
• pp.151-161
• /
• 1998

The odd spherical non-commutative tori $\mathbb{S}_{\omega}$ were defined in [2]. Assume that no non-trivial matrix algebra can be factored out of $\mathbb{S}_{\omega}$, and that the fibres are isomorphic to the tensor product of a completely irrational non-commutative torus with a matrix algebra $M_{km}(\mathbb{C})$. It is shown that the tensor product of $\mathbb{S}_{\omega}$ with the even Cuntz algebra $\mathcal{O}_{2d}$ has the trivial bundle structure if and, only if km and 2d - 1 are relatively prime, and that the tensor product of $\mathbb{S}_{\omega}$ with the generalized Cuntz algebra $\mathcal{O}_{\infty}$ has a non-trivial bundle structure when km > 1.