• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제16권4호
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• pp.217-223
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• 2012

In this note we examine the effects on subnormality of adding a new weight or changing some weights for a given subnormal weighted shift. We consider a subnormal weighted shift with a positive point mass at the origin by means of continuous functions. Finally, we introduce some methods for evaluating point mass at the origin about moment measures associated with weighted shifts.

• Journal of the Optical Society of Korea
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• 제2권1호
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• pp.30-33
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• 1998

We present the analysis of phase-shifted fiber Bragg gratings by coupled-mode equations. The transmission is expressed as that of a Fabry-Perot resonator with complex reflectance and complex transmittance. The transmission spectrum, the effective cavity length, and the behaviors with different phase-shifts are investigated. A very flattered transmission peak is obtained by introducing three phase-shifts in a grating.

• Journal of applied mathematics & informatics
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• 제23권1_2호
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• pp.435-443
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• 2007

An important approach towards solving the scattered data problem is by using radial basis functions. However, for a large class of smooth basis functions such as Gaussians, the existing theories guarantee the interpolant to approximate well only for a very small class of very smooth approximate which is the so-called 'native' space. The approximands f need to be extremely smooth. Hence, the purpose of this paper is to study approximation by a scattered shifts of a radial basis functions. We provide error estimates on larger spaces, especially on the homogeneous Sobolev spaces.

• Kyungpook Mathematical Journal
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• 제53권2호
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• pp.185-189
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• 2013

In this note we study a class of invertible weighted bilateral shifts on Hilbert space introduced by Haskell Rosenthal recently. We show that every Rosenthal shift is unitarily equivalent to its inverse, not quasisimilar to its adjoint, and has a nontrivial hyperinvariant subspace.

• Journal of Korean Vacuum Science & Technology
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• 제2권2호
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• pp.57-62
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• 1998

The resonance frequencies, shunt impedances and Q-values for the higher-order modes in our designed cavity are calculated by the computer codes URMEL and MAFIA. A new computer code is developed to calculate the complex tune shifts for the randomness of the higher-order mode frequencies due to the construction errors of a cavity. The results with the construction errors are compared to those fo without error cases for the dipole mode and quadrupole mode.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제11권4호
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• pp.47-54
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• 2007

In [6] some computation of spectral measures induced by normal operators $T^{*n}T^n$ was introduced. In this note we improve some computations by using spectral measures, which are related t o extremal vectors. Also, we discuss the extremal value properties and apply our spectral measure equations to moment sequences which are induced by weighted shifts.

• Bulletin of the Korean Chemical Society
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• 제7권6호
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• pp.433-438
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• 1986

Two new types of NMR shift reagents, one giving dipolar-only and the other giving contact-only shifts, can be prepared simply by mixing two appropriate $Ln(fod)_3$(Ln = Pr, Nd, Eu, and Yb) reagents in certain ratios. The $^1H$ and $^{13}C$ NMR spectra of pyridine-type substrates, quinoline and isoquinoline, whose paramagnetic shifts are normally a composite of contact and dipolar contributions with single lanthanide shift reagents, show the feasibility of this approach.

• 대한수학회논문집
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• 제34권2호
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• pp.477-486
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• 2019

Let ${\alpha}:1,(1,{\sqrt{x}},{\sqrt{y}})^{\wedge}$ be a weight sequence with Stampfli's subnormal completion and let $W_{\alpha}$ be its associated weighted shift. In this paper we discuss some properties of the region ${\mathcal{U}}:=\{(x,y):W_{\alpha}$ is semi-cubically hyponormal} and describe the shape of the boundary of ${\mathcal{U}}$. In particular, we improve the results of [19, Theorem 4.2].

• 대한수학회보
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• 제56권3호
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• pp.585-596
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• 2019

It is shown that a pair of Hilbert space operators V and W such that $V^*W=I$ (called a biisometric pair) shares some common properties with unilateral shifts when orthonormal bases are replaced with biorthogonal sequences, and it is also shown how such a pair of biisometric operators yields a pair of biorthogonal sequences which are shifted by them. These are applied to a class of Laguerre operators on $L^2[0,{\infty})$.

• 한국경제지리학회지
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• 제22권4호
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• pp.472-487
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• 2019

제지산업은 거듭되는 원료 및 공정기술의 혁신과 함께 두드러진 입지변동을 겪은 산업으로서 국가 및 지역별 생산 조건의 차이로 인해 해당 산업의 구조 및 입지가 상이하게 전개되고 있어 국가 및 지역별 사례 연구는 큰 의의를 갖는다고 하겠다. 본 연구는 국내 제지산업의 발달과정에서 나타나는 입지 변동에 주목하고 이를 생산요소 조건과 시장 및 정부 정책을 중심으로 설명하였다. 먼저, 20세기 초반부터 오늘에 이르기까지 국내 펄프·제지산업은 생산요소 조건, 특히 원료 조건의 변화와 관련하여 펄프공정 중심에서 제지공정 중심으로 산업의 구조가 변화되었음을 고찰하였다. 둘째, 오늘날 제지산업계에서는 원료와 시장을 입지선정과 관련하여 어떻게 고려하고 있는지 파악하였다. 마지막으로, 1970년대 말부터 수도권에 대한 입지규제가 시행됨에 따라 제지산업의 입지 변동이 어떻게 진행되었는지 설명하였다.