• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.491-496
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• 2008

Properties of pectin extracted from flesh of Asian pear in 3 cultivars were investigated at different growth stages. The extraction yields of pectin by the acidic treatment decreased during the growth. The $L^*$ value of young fruit was lower than unripe and ripe fruit, and $a^*$ and $b^*$ value were higher in the same cultivars. The degree of esterification (DE) and intrinsic viscosity of pectin were 21.1-41.3% and 1.90-3.81 dL/g, respectively. The pectin extracted from flesh of pear showed about 30% glucose retarding effect. The DE value had a high correlation with retarding effect on glucose transport and intrinsic viscosity (p<0.01 and p<0.05). The intrinsic viscosity of the pectin seems to affect the retardation of glucose transport in blood. Pectin extracted from flesh of Asian pear by acidic treatment could be a good source to develop low calorie and functional food.

• Proceedings of the Korean Information Science Society Conference
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• 2008.06b
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• pp.171-175
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• 2008

최근 TV, DVD, AV 등의 각종 가전기기가 보급되면서 사용자는 다수의 리모컨을 조작하고 기기 사이의 관계를 이해해야 다양한 서비스를 제공받을 수 있게 되었다. 하지만 사용자는 보통 기기 단위의 기능을 일일이 제어하기 보다는 간단한 조작으로 다수 기기의 기능이 복합적으로 함축된 상위수준의 서비스를 제공받기 원한다. 기존에는 다수의 기기를 조작하기 위해 각 기기의 리모컨을 물리적으로 통합한 통합 리모컨 등이 제안되었으나 고수준의 서비스를 위해서는 사용자가 각 기기를 직접 조작해야 했고, 복수의 작업을 하나의 버튼으로 수행하는 매크로 기능 등은 사용자가 직접 설계해야 하거나 직관적이지 못하였다. 본 논문에서는 사용자에게 제공되는 서비스 작업 단위를 태스크로 정의하고 서비스 제공을 위해 필요한 기기 사이의 연결성과 각종 값을 내부적으로 설정하여 사용자에게 태스크 기반의 직관적인 인터페이스를 제공하는 방법을 제안한다. 기기를 일일이 조작해야 하는 기존의 통합 리모컨과 달리, 기기의 연결 상태 등을 분석하여 사용자가 이해하기 쉬운 태스크 단위로 사용자 인터페이스를 설계하고, 복수의 기기를 제어하는 작업은 기기의 상태에 따라 동작하여 사용자는 기기의 상태를 신경 쓰지 않고 서비스를 제공받는다. XML로 설계된 각 기기의 기능과 인터페이스 및 태스크의 기능과 인터페이스를 실시간으로 통합하여 현재 상태에 적적한 태스크 기반 사용자 인터페이스를 동적으로 생성한다. 본 논문에서는 사용성 평가를 통해 제안하는 방법의 유용성을 검증하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2000.04a
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• pp.122-124
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• 2000

최근 PC의 고성능화롤 PC 기반의 서버 사용이 증대되고 있다. 특히 Windows NT 는 인터넷 서비스를 제공하는 PC 기반 서버로 폭 넓게 사용되고 있다. 이러한 서버에서의 데이터 파괴는 막대한 손실을 가져 올 것이다. 데이터의 안정성과 고 가용성을 위한 방법으로 disk mirroring 기법이 여러 분야에서 사용되고 있다. 기존의 연구들은 UNIX 플랫폼에 편중되어 있고, 현실적으로 사용이 증대되고 있는 Windows 에 대한 연구는 상대적으로 빈약한 상태이다. 본 논문에서는 Windows NT device driver level에서 다수의 node에 대한 disk mirroring 기능 구현을 설계한다. Windows NT는 계층화된 driver layer로 구성되어 있으며, 구현된 mirroring module을 드라이버 계층상에 추가함으로써 기존의 기능을 변경하지 않고 새로운 기능을 추가할 수 있다.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.174-179
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• 2013

Three low-molecular compounds were isolated from methanol extracts of pear (Pyrus pyrifolia N. cv. Chuhwangbae) fruit peels using solvent fractionation, various types of column chromatogrphy (Diaion HP-20, Sephadex LH-20, and silica gel), and high performance liquid chromatography with an assay guided by 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity. The isolated compounds were identified as 2-carboxyl-4(1H)-quinolinone (kynurenic acid, 1) from butanol fraction, cis-p-coumaric acid (2) from ethyl acetate-acidic fraction, and vanillin (3) from the ethyl acetate-phenolic fraction, respectively. These isolated compounds were confirmed on the basis of the spectroscopic data of electrospray ionization mass spectrometry and nuclear magnetic resonance. This is the first time that compounds 1-3 were isolated and identified in pear.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.33 no.3
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• pp.97-103
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• 2023

Barrier films for transparent packaging materials with excellent moisture barrier properties are prepared, utilizing a nanoclay dispersion coating layer formed after a pretreatment process of plasma activation surface treatment process under vacuum at room temperature. Attention is paid on optimizing the coupling additive through the appropriate crosslinking process and optimal dispersion process of the coating process to enhance adhesion. Analysis of the functional coating thin film shows that the water vapor transmission rate is less than 10 g/m²/24 hrs (ASTM F-1249) and the oxygen transmission rate is less than 30 cc/m²/24 hrs (ASTM D3985). It is shown that water barrier properties of coating thin film prepared in this study are greater than conventional untreated films by 10 times or more. The thickness of the transparent gas barrier film is within 0.1 mm, and the transparent gas barrier complex is implemented in two layers. In the study of PET thin film interface characteristics, FT-IR experimental analysis shows the reaction activity was optimized at RDS 1.125 %.

• Korean Journal of Food Science and Technology
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• v.45 no.5
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• pp.557-564
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• 2013

We isolated and identified antioxidants from acidic and neutral ethyl acetate fractions of the peel of pear (Pyrus pyrifolia N. cv. Chuhwangbae). We isolated 4 compounds from the methanol extract, by using 3 different types of column chromatography (Sephadex LH-20, silica gel, and octadecylsilane) and preparative HPLC. We identified the isolated compounds as (S)-(+)-2-cis-abscisic acid O-${\beta}$-D-glucopyranosyl ester (compound 1), 1-[4-O-${\beta}$-D-glucopyranosyl]phenyl ethanone (picroside, compound 2), ${\beta}$-sitosterol (compound 3), and ${\beta}$-sitosteryl 3-O-${\beta}$-D-glucopyranoside (compound 4) by nuclear magnetic resonance analysis. We are the first to report the identification of compounds 1, 2, and 4 from pear.

• Food Science and Preservation
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• v.17 no.2
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• pp.275-280
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• 2010

By-products from grapes obtained during processing have been considered to be promising materialsfor various functional applications, and to have pharmaceutical properties. A grape powder was developed from a concentrate of by-products obtained during grape processing. As dextrin levels increased, the moisture content, L-, a-, and b- values all decreased, whereas sugar content generally increased. Catechin and resveratrol were detected in most samples, but quercetin was absent. Epicatechin and resveratrol levels either decreased or were not detected as dextrin concentration increased. These physiochemical properties indicate that a concentrate extracted using undiluted ethanol as solvent is optimal for industrial use.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.8
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• pp.1162-1169
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• 2016

A new method based on accelerated solvent extraction (ASE) combined with response surface methodology (RSM) has been developed for optimization of the extraction of ginsenoside [Rb1, Rg1, and Rg3(20S)], total phenolics, and benzopyrene in red ginseng. The RSM method, based on a five level and two variable central composite design, was employed to obtain the optimal combination of extraction conditions. In brief, ginsenosides Rb1, Rg1, and Rg3(20S) and total phenolics with undetectable benzopyrene were optimally extracted with 50% ethanol as an extraction solvent, extraction temperature of $158^{\circ}C$, extraction time of 20 min, extraction pressure of 2,500 psi, flush volume of 60%, and one extraction cycle. The contents of ginsenosides and total phenolics in red ginseng extracted by ASE under optimum conditions were significantly higher than those extracted by sonication and reflux extraction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1119-1125
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• 2002

The growth of C. pefringens was inhibited by the combination of natural products which have antioxidative capacity C. perfringens was controlled very effectively by each or the combination of Paeonia japonica, Atractylodis rhizome alba, Epimedii herba, Acori graminei rhizoma, Schizandraefructus, Lyciifructus, Cinnamomi cortex Sophorae flos Phellodendri cortex, Nelumbo nuclfera gaertner, Asparagi tuber, Mori cortex radicis, Astrafali radix and Coptidis rhizome The combination of Phellodendri cortex, Epimedii herba, Astragali radtx and Glycyrrhizae radix inhibited the growth of C. pefringen by 75% and increased the antioxidative activity by 4.4 times. This combination also eliminated more than 80% of hydroxyl radical. These natural products can be utilized as pharmaceuticals, functional foods, antiaging tea, and multifunctional fermentative beverages.

• Food Science and Preservation
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• v.14 no.1
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• pp.73-77
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• 2007

The physiochemical properties of Rhododendron mucronulatum pollens were examined after the use of various extraction conditions. The levels of phenolic compounds and electron donating abilities (DPPH) were better after 80% (v/v) ethanol extraction than after water extraction. The content of phenolic compounds and the DPPH were high when the solvent ratio was 20X. The content of phenolic compounds was highest at $45^{\circ}C$ (347.60 mg/100 g). The DPPH was highest, at 67.93%, when extraction was performed at $25^{\circ}C$. An extraction time of 6 hr yielded the highest content of phenolic compounds (312.63 mg/100 g). The DPPH did not vary with extraction time. Both the levels of phenolic compounds and DPPH values rose when extractions were performed twice. In summary, a solvent ratio of 20X, an extraction temperature of $25-45^{\circ}C$, double extraction and an extraction time of 6 hare optimal for extraction, with maximal DPPH and phenolic content, of Jindalrae pollens.