• Journal of the Korean Mathematical Society
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• v.54 no.1
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• pp.281-302
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• 2017

For a Banach space operator $A{\in}B(\mathcal{X})$, let ${\sigma}(A)$, ${\sigma}_a(A)$, ${\sigma}_w(A)$ and ${\sigma}_{aw}(A)$ denote, respectively, its spectrum, approximate point spectrum, Weyl spectrum and approximate Weyl spectrum. The operator A is polaroid (resp., left polaroid), if the points $iso{\sigma}(A)$ (resp., $iso{\sigma}_a(A)$) are poles (resp., left poles) of the resolvent of A. Perturbation by compact operators preserves neither SVEP, the single-valued extension property, nor the polaroid or left polaroid properties. Given an $A{\in}B(\mathcal{X})$, we prove that a sufficient condition for: (i) A+K to have SVEP on the complement of ${\sigma}_w(A)$ (resp., ${\sigma}_{aw}(A)$) for every compact operator $K{\in}B(\mathcal{X})$ is that ${\sigma}_w(A)$ (resp., ${\sigma}_{aw}(A)$) has no holes; (ii) A + K to be polaroid (resp., left polaroid) for every compact operator $K{\in}B(\mathcal{X})$ is that iso${\sigma}_w(A)$ = ∅ (resp., $iso{\sigma}_{aw}(A)$ = ∅). It is seen that these conditions are also necessary in the case in which the Banach space $\mathcal{X}$ is a Hilbert space.

• Journal of the Korean Mathematical Society
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• v.47 no.2
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• pp.235-246
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• 2010

A Banach space operator A $\in$ B(X) is polaroid if the isolated points of the spectrum of A are poles of the resolvent of A; A is hereditarily polaroid, A $\in$ ($\mathcal{H}\mathcal{P}$), if every part of A is polaroid. Let $X^n\;=\;\oplus^n_{t=i}X_i$, where $X_i$ are Banach spaces, and let A denote the class of upper triangular operators A = $(A_{ij})_{1{\leq}i,j{\leq}n$, $A_{ij}\;{\in}\;B(X_j,X_i)$ and $A_{ij}$ = 0 for i > j. We prove that operators A $\in$ A such that $A_{ii}$ for all $1{\leq}i{\leq}n$, and $A^*$ have the single-valued extension property have spectral properties remarkably close to those of Jordan operators of order n and n-normal operators. Operators A $\in$ A such that $A_{ii}$ $\in$ ($\mathcal{H}\mathcal{P}$) for all $1{\leq}i{\leq}n$ are polaroid and have SVEP; hence they satisfy Weyl's theorem. Furthermore, A+R satisfies Browder's theorem for all upper triangular operators R, such that $\oplus^n_{i=1}R_{ii}$ is a Riesz operator, which commutes with A.

• Journal of Korean Ophthalmic Optics Society
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• v.8 no.2
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• pp.135-151
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• 2003

This study compared the effect of Polaroid$^{(R)}$ lenses on binocular vision by assessing visual acuity, stereopsis, and visual evoked potential(VEP), through Polaroid$^{(R)}$, CR 39 and sunglass lenses. The spectral absorptions of Polaroid$^{(R)}$, CR 39 and sunglass lenses were measured using a spectrophotometer (Hitachi. U-3501). The VEP were recorded by the Nicolet system. Thirty normal adult(fifteen males, fifteen females, mean=21.9 years, range=20 to 25) subjects were recorded. The subjects were provided a history including : general health, family health, medication, genetics, allergy and disease. All had normal or corrected to normal acuity with no history of visual disorders. Corrected visual acuity, colour vision and stereopsis were recorded for each subject monocularly and binocularly. Each test was repealed through the sunglass, CR 39, and Polaroid$^{(R)}$ lenses. Subjects viewed the VEP stimulus both monocularly and binocularly through the test lenses while the VEPs were recorded. The results suggest that the binocular visual acuity and stereoacuity is better than with monocular vision. On other hand, the analysis of VEP suggests that the amplitude of wave is smaller when the monocular eye receives the VEP stimulus compared with that when the binocular eye is stimulated by the VEP target with the sunglass, CR 39, and Polaroid$^{(R)}$ lens. But, the latency period of each eye was similar to results between the dominant eye and the non-dominant eye by the CR 39, sunglass, and polaroid lens. In conclusion, this study indicates that the binocular vision appears to be better through the brown Polaroid$^{(R)}$ lens than through the other test lenses.

• Journal of the Korean Graphic Arts Communication Society
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• v.2 no.1
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• pp.23-33
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• 1984

Color providing compounds on image transfer process in color photo graphy was studied with polaroid and Kodak products as a model. These compounds was inititally alkali-mobile or alkali-immobile. Alkali-mobile compunds require imagewise immobilifation in the process or alkali immoble compounds require mobilization by the cleavage reaction. As a result of studies, the polaroid products was showed alkali mobile and Kodak product represented alkali immobile.

• Proceedings of the Korean Society of Radiological Science
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• 1995.10a
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• pp.142.2-144
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• 1995

• Kyungpook Mathematical Journal
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• v.55 no.4
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• pp.885-892
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• 2015

In this paper, we mainly obtain the following assertions: (1) If T is a quasi-*-n-paranormal operator, then T is finite and simply polaroid. (2) If T or $T^*$ is a quasi-*-n-paranormal operator, then Weyl's theorem holds for f(T), where f is an analytic function on ${\sigma}(T)$ and is not constant on each connected component of the open set U containing ${\sigma}(T)$. (3) If E is the Riesz idempotent for a nonzero isolated point ${\lambda}$ of the spectrum of a quasi-*-n-paranormal operator, then E is self-adjoint and $EH=N(T-{\lambda})=N(T-{\lambda})^*$.

• Communications of the Korean Mathematical Society
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• v.27 no.1
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• pp.77-95
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• 2012

For a bounded linear operator T we prove the following assertions: (a) If T is algebraically (p, k)-quasihyponormal, then T is a-isoloid, polaroid, reguloid and a-polaroid. (b) If $T^*$ is algebraically (p, k)-quasihyponormal, then a-Weyl's theorem holds for f(T) for every $f{\in}Hol({\sigma}T))$, where $Hol({\sigma}(T))$ is the space of all functions that analytic in an open neighborhoods of ${\sigma}(T)$ of T. (c) If $T^*$ is algebraically (p, k)-quasihyponormal, then generalized a-Weyl's theorem holds for f(T) for every $f{\in}Hol({\sigma}T))$. (d) If T is a (p, k)-quasihyponormal operator, then the spectral mapping theorem holds for semi-B-essential approximate point spectrum $\sigma_{SBF_+^-}(T)$, and for left Drazin spectrum ${\sigma}_{lD}(T)$ for every $f{\in}Hol({\sigma}T))$.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.3_1spc
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• pp.615-621
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• 2013

A blind system for window glass has been designed and manufactured as a CapStone Design project at Seoul National University of Science and Technology. This system automatically controls the interior illuminance to maintain a uniform temperature. The aim of this project was to support an air conditioning system and heating equipment to maintain a good indoor environment. Proportional integral differential (PID) control using cadmium sulfide (CdS) sensors was applied to control it. Polaroid film was attached to the new blind system to reflect sunlight. It was found that the system had the potential to reduce energy consumption and may be used with a building energy management system (BEMS).

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.6
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• pp.743-748
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• 2009

In this paper, we propose an effective method to extract background components in automated vision inspection system for polarized film used in TFT LCD display panels. The test image signals are typically composed of three components such as ununiform background, random noises and target defect signals. It is important to analyze the background signal for accurate extraction of defect components. Two dimensional continuous wavelets with first derivative gaussian is used. This methods can be applied for reliable extraction of defect signal by elimination of the background signal from the original image. The proposed method outperforms over conventional FFT methods.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.04a
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• pp.1546-1548
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• 2011

최근 스마트폰의 보급률이 높아짐에 따라 스마트폰에 탑재된 카메라의 사용 또한 급증하고 있다. 이에 스마트폰으로 촬영한 사진에 효과를 적용하고 꾸미는 작업에 대한 사용자의 요구가 증가하고 있다. 본 논문에서는 사진에 폴라로이드 효과를 적용하고 다양한 꾸미기 기능을 제공하는 안드로이드 기반 스마트폰 어플리케이션인 Polandroid를 제안하고 구현하였다.