• Kyungpook Mathematical Journal
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• 제58권4호
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• pp.711-732
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• 2018

In this paper, we give a new approach to solving the 2-variable subnormal completion problem (SCP for short). To this aim, we extend the notion of recursively generated weighted shifts, introduced by R. Curto and L. Fialkow, to 2-variable case. We next provide "concrete" necessary and sufficient conditions for the existence of solutions to the 2-variable SCP with minimal Berger measure. Furthermore, a short alternative proof to the propagation phenomena, for the subnormal weighted shifts in 2-variable, is given.

• 전자공학회논문지S
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• 제35S권2호
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• pp.146-156
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• 1998

Thispapr proposes hybrid navigation parameter estimation using sequential aerial images. The proposed navigation parameter estimation system is composed of two parts: relative position estimation and absolute position estimation. the relative position estimation recursively computes the current velocity and absolute position estimation. The relative position estimation recursively computes the current velocity and position of an aircraft by accumulating navigation parameters extracted from two succesive aerial images. Simple accumulation of parameter values decreases reliability of the extracted parameters as an aircraft goes on navigating. therefore absolute position estimation is required to compensate for position error generated in the relative position step. The absolute position estimation algorithm combining image matching and digital elevation model(DEM) matching is presented. Computer simulation with real aerial image sequences shows the efficiency of the proposed hybrial algorithm.

• East Asian mathematical journal
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• 제40권1호
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• pp.25-36
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• 2024

Full univariate moment problems have been studied using continued fractions, orthogonal polynomials, spectral measures, and so on. On the other hand, the truncated moment problem has been mainly studied through confirming the existence of the extension of the moment matrix. A few articles on the multivariate moment problem implicitly presented about some results of this note, but we would like to rearrange the important results for the existence of a representing measure of a moment sequence. In addition, new techniques with orthogonal polynomials will be introduced to expand the means of studying truncated moment problems.

• 한국CDE학회논문집
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• 제1권3호
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• pp.224-233
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• 1996

An automatic mesh generation scheme with triangular finite elements on three-dimensional surfaces has been developed. The surface triangulation process is performed as follows. To begin, surfaces with key nodes are transformed to two-dimensional planes and the meshes with triangular elements are constructed in these planes. Finally, the constructed meshes are transformed back to the original 3D surfaces. For the mesh generation, an irregular mesh generation scheme is employed in which local mesh densities are assigned by the user along the boundaries of the analysis domain. For this purpose a looping algorithm combined with an advancing front technique using basic operators has been developed, in which the loops are recursively subdivided into subloops with the use of the best split lines and then the basic operators generate elements. Using the split lines, the original boundaries are split recursively until each loop contains a certain number of key nodes, and then using the basic operators such as type-1 and type-2, one or two triangular elements are generated at each operation. After the triangulation process has been completed for each meshing domain, the resulting meshes are finally improved by smoothing process. Sample meshes are presented to demonstrate the versatility of the algorithm.

• 한국통신학회논문지
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• 제33권5C호
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• pp.403-412
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• 2008

본 논문은 등가의 Wiener-Hopf 방정식의 해를 LMS 알고리즘을 이용하여 구할 수 있는 방법과 격자필터에서 직접적으로 TDL 필터의 계수를 구할 수 있는 방법을 제안한다. 이를 위해 격자필터를 이용하여 생성한 직교입력 신호를 등가의 Wiener-Hopf 방정식에 적용하여 그 해를 최소평균자승 알고리즘을 이용하여 순환적으로 구하는 방법을 보인다. 이와 같은 경우 기존에는 오차와 regression 계수를 순환적으로 구할 수 있는데 반하여 본 논문에서는 오차와 TDL 필터의 계수를 순환적으로 구할 수 있는 장점이 있다. 또한 제안한 알고리즘의 수렴적 특성을 이론적으로 고찰하였다. 그 결과는 전통적 해석과 유사하게 나타남을 알 수 있었다. 성능 평가 결과를 통해 제안한 알고리즘이 매우 우수한 성능을 나타내고 있음을 확인하였다.

• 정보보호학회논문지
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• 제5권1호
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• pp.3-16
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• 1995

본 논문에서는 저차의 부울 함수를 연접시켜 고차의 부울 함수를 생성하는 방법을 소개하고, 이러한 방법으로 생성된 함수의 균등성, 비선형성, 무상관도 등의 제반 성질을 새롭게 규명한다. 또한, 두 함수 사이의 'uncorrelated'개념을 확장하여 Differential Cryptanalysis에 강한 S-box가 가져야 할 필요 조건으로 Strict Uncorrelated Criterion(SUC) 개념을 정의하고, 이를 만족하는 부울 함수를 제시하여 그 존재성을 밝히고 특히, 특수한 형태의 연접으로 생성한 함수가 이를 유지함을 보인다. 그리고, Walsh-Hadamard 변환을 이용하여 부울 함수의 상관관계 특성을 조사하여 이를 연접 방식으로 확장 재생성한 부울 함수에 적용, 이들 함수의 상관관계 특성을 조사하여 이를 연접 방식으로 확장 재생성한 부울 함수에 적용, 이들 함수의 상관관계 특성을 규명한다. 더불어 bent 함수들의 연접으로 홀수차 벡터공간 위에서 semi-bent 함수를 정의하고 이 함수에 대한 상관관계 특성과 비선형치를 규명함과 동시에 SUC을 만족함을 증명하며 연접 방식에 의해서 확장 재생성된 다른 형태의 부울 함수와 비교하여 semi-bent 함수의 암호학적 우수성을 입증한다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.82-85
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• 2005

Doxorubicin is a highly-valuable anthracycline-family polyketide drug with a very potent anticancer activity, typically produced by a Gram-positive soil bacterium called Streptomyces peucetius. Thanks to the recent development of Streptomyces genomics-based technologies, the random mutagenesis approach for Streptomyces strain improvement has been switched toward the genomics-based technologies including the application of DNA microarray systems. In order to identify and characterize the genomics-driven potential target genes critical for doxorubincin overproduction, three different types of doxorubicin overproducing strains, a dnrI(doxorubicin-specific positive regulatory gene)-overexpressor, a doxA (gene involved in the conversion from daunorubicin to doxorubicin)-overexpressor, and a recursively-mutated industrial strain, were generated and examined their genomic transcription profiles using Streptomyces DNA microarray systems. The DNA microarray results revealed several potential target genes in S. peucetius genome, whose expressions were significantly either up- or down-regulated comparing with the wild-type strain. A systematic understanding of doxorubicin overproduction at the genomic level presented in this research should lead us a rational design of molecular genetic strain improvement strategy.

• Journal of applied mathematics & informatics
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• 제26권3_4호
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• pp.673-678
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• 2008

Let $W_{\alpha}$, be a recursively generated quadratically hyponormal weighted shift with a weight sequence ${\alpha}$ : 1, (1, $\sqrt{x}$, $\sqrt{y}$)$^{\wedge}$. In [4] Curto-Jung showed that R = {(x,y) : $W_{1,\;(1,\;{\sqrt{x}},\;{\sqrt{y}})^{\wedge}}$ is quadratically hyponormal} is a closed convex with nonempty interior, which guarantees that there are a lot of quadratically hyponormal weighted shifts with first two equal weights. They suggested a problem computing expressions of certain extremal points of R. In this note we obtain a partial answer of their extremal problem.

• Industrial Engineering and Management Systems
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• 제10권1호
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• pp.15-23
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• 2011

This research considers scheduling problems with jobs which can be divided into sub-jobs and do not required to be processed immediately following one another. Heuristic algorithms considering how to divide jobs are proposed in an attempt to find near-optimal solutions within reasonable run time. The algorithms contain two phases which are executed recursively. Phase 1 of the algorithm determines how jobs should be divided while phase 2 solves the scheduling problem given the sub-jobs established in phase 1. Simulated annealing and genetic algorithms are applied for the two phases and four heuristic algorithms are established. Numerical experiment is conducted to determine the best parameter values for the heuristic algorithms. Examples with different sizes and levels of complexity are generated. Performance of the proposed algorithms is evaluated. It is shown that the proposed algorithms are able to efficiently and effectively solve the considered problems.

• Journal of Mechanical Science and Technology
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• 제18권4호
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• pp.550-559
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• 2004

In this paper, a recursive formulation for generating the equations of motion of spatial mechanical systems is presented. The rigid bodies are replaced by a dynamically equivalent constrained system of particles which avoids introducing any rotational coordinates. For the open-chain system, the equations of motion are generated recursively along the serial chains using the concepts of linear and angular momenta Closed-chain systems are transformed to open-chain systems by cutting suitable kinematic joints and introducing cut-joint constraints. The formulation is used to carry out the dynamic analysis of multi-link five-point suspension. The results of the simulation demonstrate the generality and simplicity of the proposed dynamic formulation.