• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.818-823
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• 1998

A three-arm PWM UPS is realizable low price and small size UPS. In this UPS configuration, the center arm operates in both PWM converter mode and PWM inverter mode. Therefore, the operation of this UPS differs from the conventional UPS. In this paper, the three-arm PWM UPS is analyzed and a trial product is realized.

• Natural Product Sciences
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• 제16권3호
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• pp.198-201
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• 2010

Acanthopanax divaricatus var. albeofructus is one of the indigenous medicinal plant and the fruits of Acanthopanax spp. used as a remedial for "wipe out evil wind". Two anthocyanin were isolated from the fruits of Acanthopanax divaricatus var. albeofructus. Their structures were elucidated as cyanidin 3-lathyroside (1) and cyanidin 3-galactoside (2) by chemicophysical and spectroscopic analysis. And also, four chemical, syringin, chlorogenic acid, caffeic acid and acanthoside D were identified. Both anthocyanide were isolated for the first time from Acanthopanax species. cyanidin 3-lathyroside is one of the rare anthocyanin in natural resources.

• 충청수학회지
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• 제27권4호
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• pp.735-743
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• 2014

We obtain a splitting theorem which characterizes when a given space is a catesian product of an $H^f$-space, and also obtain a dual theorem for a co-$H^g$-space. Then we get Dula and Gottlieb's results as corollaries.

• 전기전자학회논문지
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• 제25권3호
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• pp.544-547
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• 2021

Recently, various display products are being applied to automobiles. In the process of acquiring an image from a display product, a large amount of additive white Gaussian noise(AWGN) is generated. Generally known denoising techniques focus on removing noise, so detailed components including image information are proportionally lost in the process of removing noise. The algorithm proposed in this paper proposes a method to effectively remove noise while preserving the detail of image information.

• Bulletin of the Korean Chemical Society
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• 제7권2호
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• pp.150-153
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• 1986

Co-sensitized photooxygenation of 1,1-diphenyl-2-vinylcyclopropane (VCP-DPh) with 9,10-dicyanoanthracene and biphenyl in oxygen-saturated acetonitrile solution produced 3,3-diphenyl-5-vinyl-1,2-dioxolane as the major product. The same photoproduct was obtained by acetone sensitized photooxygenation in oxygen-saturated acetone solution. However, VCP-DPh remained intact when directly irradiated with DCA or irradiated with Rose Bengal to generate singlet oxygen. A mechanism involving a cosensitizer radical cation and sensitizer radical anion is proposed.

• Journal of Magnetics
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• 제7권3호
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• pp.115-125
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• 2002

We proposed a novel method to evaluate the magnetic properties of the initial layer and the columnar structure separately for CoCr-based perpendicular recording media. We show that the thickness of the initial layer and the intrinsic magnetocrystalline anisotropy of columnar structure can be quantitatively evaluated using the plotted product of perpendicular anisotropy to magnetic film thickness versus magnetic film thickness ($K_{u{\bot}}^{ex{p.}}$ $\times$ d$_{mag.}$ vs. d$_{mag.}$ plot). Based on the analyses, it is found that: (1) compared with CoCrPtTa media, CoCrPtB media have relatively thin initial layer, and have fine grains with homogeneous columnar structure with c-plane crystallographic orientation; (2) CoCrPtB media can be grown epitaxially on Ru or CoCr/C intermediate layer, and as the result, the magnetic properties of the media within thin thickness region of d$_{mag.}$ $\leq$ 20 nm is significantly improved; (3) the key issue of material investigation for CoCr-based perpendicular recording media will be focused on how to fabricate c-plane-oriented columnar grains well isolated with nonmagnetic substance in epitaxial-growth media, while maintaining the thermal stability of the media.

• Asian-Australasian Journal of Animal Sciences
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• 제16권4호
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• pp.588-595
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• 2003

The optimum level of fresh granulated low-calcium (0.2%) skim milk co-precipitate, as fat substitute in low-fat ground pork patties was determined on the basis of physico-chemical, cooking and sensory properties. Low-fat ground pork patties (<10% total fat), formulated with 15 per cent water, 4 per cent added fat, 1.5 per cent salt and 4-10 per cent milk co-precipitate, were evaluated for proximate composition, cooking characteristics and compared with control patties with 15 % added fat. The moisture and protein content of raw and cooked low-fat patties were significantly (p<0.05) higher than control. The incorporation of milk co-precipitate in low-fat patties improved cooking yield, fat and moisture retention and reduced shrinkage. The sensory properties of low-fat patties were comparable with control patties. The overall acceptability of low-fat patties formulated with 7% milk co-precipitate was significantly (p<0.05) higher than patties with 10% level and non-significantly (p<0.05) higher than low-fat patties containing 4% milk co-precipitate and control. Instrumental Texture Profiles of developed low-fat patties and control patties were comparable with slight increases in hardness and gumminess of the low-fat product. The developed low-fat ground pork patties (7% milk co-precipitate) had lower TBA values, better microbiological and sensory refrigerated storage stability than high-fat control patties packaged in air permeable films for 21 days.

• 한국응용과학기술학회지
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• 제30권4호
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• pp.770-778
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• 2013

In this study, a liquid carbonation method was applied for producing precipitate calcium carbonate by liquid-liquid reaction. We recycled the recycling water of ready-mixed concrete, one of construction waste for use source of carbonate ion. A supernatant separated from the recycling water of ready-mixed concrete, as a result of ICP analysis of a cation, $Ca^{2+}$ was contained up to 1100 ppm. We used MEA as a $CO_2$ absorbent for the liquid carbonation. A precipitate $CaCO_3$ was produced at more than MEA 20 wt%. The precipitate $CaCO_3$ as a final product was separated and dried. The result of XRD was confirmed the generation of $CaCO_3$ to calcite structure.

• 한국연소학회지
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• 제13권1호
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• pp.1-9
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• 2008

Emission characteristics of NOx and CO with heat loss under high efficiency combustion conditions of $CH_4$/Air prmixed flame were examined numerically using detailed-kinetic chemistry. The one-dimensional combustor length was fixed 5cm, and the equivalence ratio was varied from 0.75 to 0.95. To consider the effects of heat loss on NOx and CO formation, the radiative heat loss rate and combined heat loss rate of conductive and convective heat transfer are included. The following conclusions were drawn. In order to reduce the NOx and CO emission level simultaneously, the temperature of product gases must be reduced under 1,800K as soon as possible but kept over 1,300K during the residence time which is needed to converge CO to $CO_2$.

• 공업화학
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• 제3권1호
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• pp.72-80
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• 1992

상이동촉매를 사용하여 Group 6의 $M(CO)_4$(2, 2'-bipyridine)[M=Cr, Mo, W]을 $M(CO)_6$의 CO 리간드를 2개의 비공유 전자쌍 주게인 2, 2'-bipyridine으로 치환하여 합성할 때 촉매의 종류와 용매가 생성물의 수율에 미치는 영향을 고찰하였다. 촉매는 형태, 중심양이온 및 음이온의 종류, 양이온에 결합된 알킬기와 아릴기의 종류, 그리고 사슬길이가 다른 다양한 촉매를 사용하였다.