• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.2
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• pp.75-80
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• 2004

Vehicle structures are composed of many substructure connected to one another by various types of mechanical joints. In vehicle engineering it is important to study these connected structures under various dynamic forces for the evaluations of fatigue life and stress concentration exactly. It is difficult to obtain the accurate load history of specified positions because of the errors such as modeling, measurement and etc. In the beginning of design exact load data are actually necessary for the fatigue strength and life analysis to minimize the cost and time of designing. In this paper, the procedure of practical dynamic force determination is developed by the combination of the principal stresses of F. E. Analysis and experiment. Least square pseudo inverse matrix is adopted to obtain in inverse matrix of analyzed stresses matrix. The error minimization method utilizes the inaccurate measured error and the shifting error that the whole data is stiffed over real data. The least square criterion is adopted to avoid these non. Finally, to verify the proposed procedure, a bus is analyzed. This measurement and prediction technology can be extended to the structural modification of any geometric shape in complex structure.

• Journal of Microbiology and Biotechnology
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• v.33 no.1
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• pp.15-27
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• 2023

The incidence of melioidosis cases caused by the gram-negative pathogen Burkholderia pseudomallei (BP) is seeing an increasing trend that has spread beyond its previously known endemic regions. Biofilms produced by BP have been associated with antimicrobial therapy limitation and relapse melioidosis, thus making it urgently necessary to understand the mechanisms of biofilm formation and their role in BP biology. Microbial cells aggregate and enclose within a self-produced matrix of extracellular polymeric substances (EPSs) to form biofilm. The transition mechanism of bacterial cells from planktonic state to initiate biofilm formation, which involves the formation of surface attachment microcolonies and the maturation of the biofilm matrix, is a dynamic and complex process. Despite the emerging findings on the biofilm formation process, systemic knowledge on the molecular mechanisms of biofilm formation in BP remains fractured. This review provides insights into the signaling systems, matrix composition, and the biosynthesis regulation of EPSs (exopolysaccharide, eDNA and proteins) that facilitate the formation of biofilms in order to present an overview of our current knowledge and the questions that remain regarding BP biofilms.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.3
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• pp.216-221
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• 2009

Purpose: The retention of the basement membrane complex, which was the unique feature of the acellular dermal matrix ($AlloDerm^{(R)}$), plays an important role in the normal process of wound healing. The present study was aimed to compare the healing of the acellular dermal matrix according to the graft method in the rabbit ear. Materials and methods: Six mature rabbits weighing about 3.0 kg were used, $10\;{\times}\;5\;mm$ sized subcutaneous pockets were created between the ear skin and the underlying perichondrium. In the control group, the acellular dermal matrix was grafted with the basement membrane facing toward the perichondrium. On the contrary, the acellular dermal matrix was grafted with the basement membrane facing toward the skin side in the experimental group I. In the experimental group II, the acellular dermal matrix was grafted like rolled configuration with basement membrane side in. The grafted site was picked at 3, 7, and 21 days after the graft. Serial sections were processed by H-E stain and examined under light microscopy to assess the healing patterns. Results: There was no distinct volume loss in the gross examination, but resorption was observed from the edge of the acellular dermal matrix in the histological examination. The space of resorption was replaced by the newly formed fibrous tissues and vessels. The inflammatory cells were more increased at 7 days after the graft than the early days. However, inflammation was decreased at 21 days after the graft. Regardless of the graft direction, no differences were observed between the control and the experimental group I in the healing patterns. Conclusion: These results suggest that the acellular dermal matrix can be used simply and effectively without regard to the graft direction as a substitute of autogenous material for repairing soft tissue defect.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.25-33
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• 2015

As a reversible Jacket is having the compatibility of two sided wearing, the matrix that both the inside and the outside are compatible is called Jacket matrix, and the matrix is having both inside and outside by the processes of element-wise inverse and block-wise inverse. This concept had been completed by one of the authors Moon Ho Lee in 1989, and finally that resultant matrix has been christened as Jacket matrix, in 2000. This is the most generalized extension of the well known Hadamard matrices, which includes both orthogonal and non-orthogonal matrices. This matrix addresses many problems in information and communication theories. we investigate the properties of the Jacket matrix, i.e. determinants, eigenvalues, and kronecker product. These computations are very useful for signal processing and orthogonal codes design. In our proposal, we provide some results to calculate these values by using a very simple mathematical model with less complexity.

• Communications of the Korean Mathematical Society
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• v.35 no.1
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• pp.137-149
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• 2020

Let γ⁽ⁿ⁾ ≡ {γ_ij} (0 ≤ i+j ≤ 2n, |i-j| ≤ n) be a sequence in the complex number set ℂ and let E (n) be the Embry truncated moment matrices corresponding from γ⁽ⁿ⁾. For an odd number n, it is known that γ⁽ⁿ⁾ has a rank E (n)-atomic representing measure if and only if E(n) ≥ 0 and E(n) admits a flat extension E(n + 1). In this paper we suggest a related problem: if E(n) is positive and nonsingular, does E(n) have a flat extension E(n + 1)? and give a negative answer in the case of E(3). And we obtain some necessary conditions for positive and nonsingular matrix E (3), and also its sufficient conditions.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.696-699
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• 1997

In this paper, we presents that for discrete system with matched perturbation of uncertain parameters in the state coefficient matrix A(i.e., with perturbation of A in the range of the input matrix B), the poles of the perturbed closed loop system can be placed into the preassigned circle by the static-state feedback. We discuss the robust stabilization of the system satisfying the matching condition and application to the controller design problem.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.337-342
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• 2004

Since 1992, Philips has been developing polymer OLEDs resulting in a first commercial monochrome display just 10 years later. Philips is now focusing on the technology development required to mass-produce full-color polymer OLDE displays, based on passive and active-matrix addressing. High precision inkjet printing has been chosen as the deposition technology for the OLED material. In this paper, we give an overview of the activities of Philips in the area of mobile OLED applications and explore the route towards large screen OLED television.

• Journal of applied mathematics & informatics
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• v.27 no.1_2
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• pp.1-12
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• 2009

Iterative algorithms are proposed for the least-squares symmetric solution of AXB = E with a submatrix constraint. We characterize the linear mappings from their independent element space to the constrained solution sets, study their properties and use these properties to propose two matrix iterative algorithms that can find the minimum and quasi-minimum norm solution based on the classical LSQR algorithm for solving the unconstrained LS problem. Numerical results are provided that show the efficiency of the proposed methods.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.191-196
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• 2004

This study proposed the analysis of mass position detection and modified stiffness due to the change of the mass and stiffness of structure by using the original and modified dynamic characteristics. The method is applied to examples of a cantilever and 3 degree of freedom by modifying the mass. The predicted detection of mass positions and magnitudes are in good agrement with these from the structural reanalysis using the modified mass.

• Communications of the Korean Mathematical Society
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• v.33 no.3
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• pp.695-704
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• 2018

In this paper, firstly we compute the spectral norm of g-circulant matrices $C_{n,g}=g-Circ(c_0,c_1,{\cdots},c{_{n-1}})$, where $c_i{\geq}0$ or $c_i{\leq}0$ (equivalently $c_i{\cdot}c_j{\geq}0$). After, we compute the spectral norms, determinants and inverses of the g-circulant matrices with the Fibonacci and Lucas numbers.