• Communications of the Korean Mathematical Society
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• v.11 no.4
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• pp.937-958
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• 1996

On the setting of product of balls we consider Toeplitz operators, with symbols satisfying a certain condition, on the Bergman space. Norms and essential norms of such operators are estimated by means of certain integral quantities.

• Bulletin of the Korean Mathematical Society
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• v.53 no.3
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• pp.681-698
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• 2016

In this paper, we investigate relative essential spectra of $2{\times}2$ block operator matrix using the Fredholm perturbation theory. Furthermore, an example for two-group transport equations is presented to illustrate the validity of the main results.

• Journal of the Korean Mathematical Society
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• v.50 no.1
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• pp.137-159
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• 2013

It is studied the linear combinations of composition operators on the Banach space of bounded harmonic functions on the open unit disk. We determine the essential norm of them.

• Korean Journal of Mathematics
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• v.24 no.1
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• pp.15-25
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• 2016

We obtain some estimations of the essential norm of a pull back operator induced by quasi-symmetric homeomorphisms. As a corollary, we deduce the compactness criterion of this operator.

• East Asian mathematical journal
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• v.19 no.2
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• pp.251-259
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• 2003

The concepts of t-rational extensions and t-essential extensions of modules, where t a preradical for R-Mod, are introduced. The structures of such extensions are determined. Relations between maximal t-rational extensions and other concepts of modules are studied.

• Mycobiology
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• v.37 no.1
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• pp.67-68
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• 2009

Antifungal activity of celery essential oil against Malassezia furfur was investigated using broth microdilution and vapor contact methods. Potent antifungal activity was evident using both methods. Fungicidal activity was revealed in the vapor contact method.

• Honam Mathematical Journal
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• v.41 no.3
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• pp.619-629
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• 2019

On the setting of the pluriharmonic Dirichlet space, we describe the essential norm of an operator which is a finite sum of products of several Toeplitz operators.

• Journal of the Chungcheong Mathematical Society
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• v.36 no.3
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• pp.155-162
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• 2023

We study permutatons that satisfy a necessary and sufficient condition for the equality of Fulton's essential set and the maximal-inversion-descent(MID) set.

• Journal of the Korean Wood Science and Technology
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• v.49 no.1
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• pp.23-43
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• 2021

In this study, we selected two essential oils, Citrus unshiu and Cinnamomum cassia with superior antioxidant effects from the essential oils of 7 wild plants in South Korea and examined their antimicrobial activity against Candida albicans, which causes dermatitis to identify the antimicrobial components in the essential oils. As a result of measuring DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity, SC50 value of the Citrus unshiu essential oil was 0.010 mg/mL, while for the Cinnamomum cassia essential oil, SC50 value was 0.09 mg/mL. In addition, when ABTS (2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity was measured, SC50 value of the Citrus unshiu essential oil was 0.09 mg/mL, while for the Cinnamomum cassia essential oil, it was 0.06 mg/mL, exhibiting high antioxidant activity. For the minimum inhibitory concentration (MIC), the essential oil of Cinnamomum cassia was 1.25 mg/mL and that of Citrus unshiu was 5 mg/mL, demonstrating a high antimicrobial activity of the Cinnamomum cassia essential oil. Through the thin layer chromatography (TLC) bioassay, we assessed the antimicrobial activity against C. albicans according to the fraction components of the two essential oils. Also, by using preparative TLC (prep. TLC), we obtained the active fractions, and by performing GC/MS analysis of the components with the same Rf value, we identified the antimicrobial-active components. As a result, the main components having antioxidant and antimicrobial activities were cinnamyl acetate, eucalyptol, linalool, and citral of the Cinnamomum cassia essential oil and linalool from the Citrus unshiu essential oil. Also, based on the analysis of the fractional components that showed antioxidant and antimicrobial activities in both of the two essential oils, it was found that linalool has antioxidant activity, while cinnamyl acetate, eucalyptol, citral, and geranyl acetate have antioxidant and antimicrobial activities.

• Mycobiology
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• v.31 no.2
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• pp.99-104
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• 2003

Bee propolis ethanolic extract with some plant essential oils was investigated for its antidermatophytic properties. The tested plant essential oils included jasmine, clove, lemon, Arabian jasmine, mint, rosa, olive and basil. The antidermatophytic activity has been compared to Naftifine-HCl and Clotrimazole used for dermatophyte treatment. Experimental model has been tested using sheep hoof plate for the in vitro tests to stimulate human nails. Mint, clove and basil with 4 mg/ml of bee propolis have a comparable efficacy to those of Naftifine-HCl and Clotrimazole. There is a great necessity for new effective low price and safe antidermatophyte agents to avoid recurrent infection. Propolis synergistic could be of great importance with essential oils of plants in dermatophyte therapy.