• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.7
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• pp.2865-2871
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• 2012

In this study, the fracture behaviour of DCB(double cantilever beam) specimen with aluminum foam composite materials is analyzed by simulation. By comparing the analysis results with two models of 25 mm and 40 mm, the model with thickness of 25 mm is weaker than 40 mm at fatigue life and damage. Two models are unfavorable at 'SAE Transmission' in case of nonuniform fatigue load and rainflow matrices are weakest at 'SAE Bracket history'. In damage matrices, the model with 25 mm of thickness is weaker than the model with 40 mm of thickness but the model with 40 mm of thickness relative damage possibility is higher than in case of 25 mm. As two models are safest at 'SAE Transmission', the relative damage becomes the lowest value from 1.1 to 1.8 %. The mechanical property can be investigated by applying these analyses results with the real composite structure bonded with adhesive and analyzing fracture behaviour.

• Proceedings of the Korean Printing Society Conference
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• 2000.12a
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• pp.0.2-0
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• 2000

Most important step for the color matching in scanner is the color coordinate transformation from the scanner RGB space to device independent uniform color space. A variety of color calibration technologies have been developed for input device. Linear or nonlinear matrices have been conveniently applied to correct the color filter\`s mismatch with color matching function in scanners. The color matching accuracy is expected to be further improved when the nonlinear matrices are optimized into subdivided smaller color spaces than in single matrix of the entire color space. This article proposed the scanner calibration method using subspace division regression analysis and it were compared with conventional method.

• Journal of the Korean Graphic Arts Communication Society
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• v.19 no.1
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• pp.4-16
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• 2001

Most important step for the color matching in scanner is the color coordinate transformation from the scanner RGB space to device independent uniform color space. A variety of color calibration technologies have been developed for input device. Linear or nonlinear matrices have been conveniently applied to correct the color filter's mismatch with color matching function in scanners. The color matching accuracy is expected to be further improved when the nonlinear matrices are optimized into subdivided smaller color spaces than in single matrix of the entire color space. This article proposed the scanner calibration method using subspace division regression analysis and it were compared with conventional method.

• Carbon letters
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• v.5 no.2
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• pp.62-67
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• 2004

Performance of carbon-carbon composites is known to be influenced by the fibre matrix interactions. The present investigation was undertaken to ascertain the development of microstructure in such composites when carbon fibres possessing different surface energies (T-300, HM-35, P120 and Dialed 1370) and pitch matrices with different characteristics (Coal tar pitch $SP110^{\circ}C$ and mesophase pitch $SP285^{\circ}C$) are used as precursor materials. These composites were subjected to two different heat treatment temperatures of $1000^{\circ}C$ and $2600^{\circ}C$. Quite interesting changes in the crystalline parameters as well as the matrix microstructure are observed and attempt has been made to correlate these observations with the fibre matrix interactions.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.9
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• pp.21-29
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• 2014

Due to enormous number of user and limited memory space, the memory saving is become an important issue for big data service these days. In the large scaled multiple-input multiple-output (MIMO) system, the Teoplitz channel can play the significance rule to improve the performance as well as power efficiency. In this paper, we propose a Toeplitz channel decomposition based on matrix vectorization. Here we use Toeplitz matrix to the channel for large scaled MIMO system. And we show that the Toeplitz Jacket matrices are decomposed to Cooley-Tukey sparse matrices like fast Fourier transform (FFT).

• Journal of Korean Society on Water Environment
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• v.25 no.1
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• pp.136-141
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• 2009

Inactivation rates between enterococci and total coliforms were compared in order to find the suitability of enterococci as an indicator microorganism under various experiment conditions - freshwater and/or seawater, indoor and/or outdoor conditions. In case of indoor laboratory experiments, inactivation rates of enterococci ($k_D$: 0.050~0.082) were faster than those of total coliforms ($k_D$: 0.034~0.045) in freshwater matrix. In seawater matrix, however, survival rate of enterococci was longer than that of total coliforms at two out of three experiments in indoor condition. When incubated in outdoor conditions, enterococci were inactivated significantly more rapidly than total coliforms both in freshwater and seawater matrices. With these results, enterococci appear to be less suitable than total coliforms in terms of inactivation rates.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.857-862
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• 2004

This paper analyzes properties of the recently developed nonlinear optimization method, Dynamic Encoding Algorithm for Searches (DEAS) [1]. DEAS locates local minima with binary strings (or binary matrices for multi-dimensional problems) by iterating the two operators; bisectional search (BSS) and unidirectional search (UDS). BSS increases binary strings by one digit (i.e., zero or one), while UDS performs increment or decrement to binary strings with no change of string length. Owing to these search routines, DEAS retains the optimization capability that combines the special features of several conventional optimization methods. In this paper, a special feature of BSS and UDS in DEAS is analyzed. In addition, a effective global search strategy is established by using information of DEAS. Effectiveness of the proposed global search strategy is validated through the well-known benchmark functions.

• Communications of the Korean Mathematical Society
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• v.17 no.1
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• pp.95-102
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• 2002

A central limit theorem is obtained for a stationary multivariate linear process of the form (equation omitted), where { $Z_{t}$} is a sequence of strictly stationary m-dimensional associated random vectors with E $Z_{t}$ = O and E∥ $Z_{t}$∥$^2$ < $\infty$ and { $A_{u}$} is a sequence of coefficient matrices with (equation omitted) and (equation omitted).ted)..ted).).

• Communications of the Korean Mathematical Society
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• v.15 no.1
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• pp.29-36
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• 2000

The T-ideal of F(X) generated by $x^{n}$ for all x $\in$ X, is generated also by the symmetric polynomials. For each symmetric poly-nomial, there corresponds one row of the incidence matrix. Finding the nilpotency of nil-algebra of nil-index n is equivalent to determining the smallest integer N such that the (n, N)-incidence matrix has rank equal to N!. In this work, we show that the (n, (equation omitted)$^{(1,....,n)}$-incidence matrix is center-symmetric.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1014-1017
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• 2009

The analytical expression for quality function is found including the dependence on disparity. The problem is considered in the projective coordinates for which the forward and backward transformation matrices are found. The formation of side observer regions is considered. The probability of the pseudo stereo effect is also estimated. Testing patterns are improved in order to provide higher accuracy of measurements. This is confirmed in experiments.