• 대한수학회논문집
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• 제16권2호
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• pp.319-332
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• 2001

The main object of this paper is first to give tow contiguous analogues of a well-known hypergeometric summation formula for $_2$F$_1$(1/2). We then apply each of these analogues with a view to evaluating the sums of several classes of series in terms of Psi(or Digamma) and the Zeta functions. Relevant connections of the series identities presented here with those given elsewhere are also pointed out.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.332-335
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• 2003

Particle size and piezoelectric characteristics of PNW-PMN-PZT ceramics with the variations in attrition milling conditions were investigated for the piezoelectric transformer application. Particle size and distribution were decreased with increasing milling time. Dielectric constant (${\varepsilon}r$), electromechanical coupling factor (kp), mechanical quality factor (Qm) and density showed the optimum value of 1563, 0.53, 2342, 7.63, respectively at 7h milling time.

• Natural Product Sciences
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• 제13권4호
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• pp.332-336
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• 2007

Five steroids and two norsesquiterpene glycosides were isolated from the methanol extract of H. japonicus. Their structures were determined by means of physio-chemical and spectral data to be friedelin (1), stigmast-5-en-3-${\beta}$-ol (${\beta}$-sitosterol) (2), 7-keto-${\beta}$-sitosterol (3), 6${\beta}$-hydroxy-4-stigmasten-3-one (4), 7${\alpha}$-hydroxy-${\beta}$-sitosterol (5), 3-hydroxy-4,4-dimethyl-4-butyrolactone (6), daucosterol (7), (6S, 9S)-roseoside (8), and (9S)-drummondol-9-O-${\beta}$-D-glucopyranoside (spinoside B) (9). The compounds 1, 3, 4, and 6 - 9 were first isolated from this plant source.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1998년도 제50차 추계 학술대회 연제집
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• pp.331-332
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• 1998

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.332-335
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• 2007

The superplastic forming (SPF) has been widely used in the automotive and aerospace industry because it has great advantages to produce very light and strong components. Finite element method (FEM) is used to model the process of superplastic forming/diffusion bonding (SPF/DB), to predict the pressure-time curve and to analyze the process parameter. In this study, process design of SPF/DB is carried out a 3-sheet sandwich part. SPF/DB process with pressure control was analyzed by using finite element method. For obtaining proper shape, step-by-step pressurization is proposed. The first step of SPD/DB process is obtained by applying of pressure in patches. From the next step it applied pressure to all regions (between inner sheets, between inner and face sheets). By using the proposed pressurization scheme, deficit in part shape is found to be eliminated.

• 대한토목학회논문집
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• 제34권1호
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• pp.329-332
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• 2014

세계 고속철도 시장의 대용량 수송 및 고속화 추세에 따라 개술개발 경쟁이 가속화되는 시점에서 국내외시장 환경의 대처와 신성장산업으로의 육성을 위한 신기술 개발의 필요성에 따라 동력분산형 고속철도시스템(최고시험속도 430km/h, 최고영업속도 370km/h)의 핵심기술개발로 HEMU-430x가 상용화를 앞두고 있다. 이는 철도선진국으로의 도약과 국내시장 뿐 아니라 세계시장 진출 도모에 계기가 될 수 있을 것으로 기대된다. 이에 본 연구에서는 고속철도의 국내 및 해외시장 규모를 파악하여 국내외 동력분산형 고속철도 도입을 대비한 기초자료로써 활용하고, 텍스트 마이닝 기법을 통한 동력분산형 고속열차의 차별화된 마케팅 전략을 수립하여 국내 시장에서의 성공적인 도입과 해외시장 진출을 위한 발판을 마련하고자 한다.

• 소성∙가공
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• 제15권4호
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• pp.326-332
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• 2006

Sandwich structures, which are composed of a thick core between two faces, are commonly used in many engineering applications because they combine high stiffness and strength with low weight. Depending on the sheets by a rolling process, which is a more efficient and economical approach compared to other types of processes, has become an increasingly important subject of study. In this paper, we made a roll forming machine which progressive forming possible and force measurement for a roll forming of the sheet metal forming. And we designed a roll molding that arrayed of embossing size 3mm in diameter fabricate micro dimple inner structure plate. We carried out forming experiment such as array change and thickness to sts304 sheet. Ultimately, this research developed inner structure plate of high stiffness.

• Journal of Magnetics
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• 제19권4호
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• pp.327-332
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• 2014

The effect of minor element additions (Ca, Al) on microstructural change and magnetic properties of Fe-Nb-Cu-Si-B alloy has been investigated, in this paper. The Fe-Si-B-Nb-Cu(-Ca-Al) alloys were prepared by arc melting in argon gas atmosphere. The alloy ribbons were fabricated by melt-spinning, and heat-treated under a nitrogen atmosphere at $520-570^{\circ}C$ for 1 h. The soft magnetic properties of the ribbon core were analyzed using the AC B-H meter. A differential scanning calorimetry (DSC) was used to examine the crystallization behavior of the amorphous alloy ribbon. The microstructure was observed by X-ray diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscope (SEM). The addition of Ca increased the electrical resistivity to reduce the eddy current loss. And the addition of Al decreased the intrinsic magnetocrystalline anisotropy $K_1$ resulting in the increased permeability. The reduction in the size of the ${\alpha}$-Fe precipitates was observed in the alloys containing of Ca and Al. Based on the results, it can be concluded that the additions of Ca and Al notably improved the soft magnetic properties such as permeability, coercivity and core loss in the Fe-Nb-Cu-Si-B base nanocrystalline alloys.

• 한국식품조리과학회지
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• 제33권3호
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• pp.325-332
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• 2017

Purpose: The study investigated the quality characteristics of cookies prepared 0, 10, 20 and 30% burdock (Arctium lappa L.) powder. Methods: Cookies were manufactured with 0%, 10%, 20%, and 30% wheat flour substituted for burdock powder. Results: Density of the dough showed no significant differences with increasing amount of burdock powder, whereas pH of the dough decreased with increasing burdock powder content. The pH of cookies decreased with increasing burdock powder content, whereas $^{\circ}brix$ of cookies increased with burdock powder content. The moisture contents of cookies increased with increasing burdock powder content. The spreadability of cookies decreased with increasing burdock powder content. The L-value of cookies decreased, a-value increased, and b-value decreased with increasing burdock powder content. The hardness of cookies decreased with increasing burdock powder content. Total polyphenol contents and DPPH radical scavenging activity increased with increasing burdock powder content (p<0.05). In the sensory evaluation, appearance, color, flavor, and texture were highest in the control group, whereas sweet taste and savory taste were highest in the added group. For overall acceptance of cookies, 10% burdock powder cookies showed higher values than the control and other samples. Conclusion: Results suggest that cookies manufactured with 10% burdock powder are the most optimal product.

• Korean Chemical Engineering Research
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• 제53권3호
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• pp.327-332
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• 2015

A large amount of dye wastewater poses a threat to environmental safety. Disperse blue, an anthraquinone dye that is widely used in textile dyes, is difficult to degrade in wastewater. In this work, one fungus was screened according to the decolorization rate of disperse blue. The fungus was identified and named Aspergillus XJ-2 on the basis of its morphological characteristics and 18s rDNA. Response surface method was used to optimize culture conditions for A. XJ-2. The optimum values of obtained responses were as follows: temperature, $35^{\circ}C$; pH, 5.2; carbon-to-nitrogen ratio, 30:5.5; and rotation ratio, $175r{\cdot}min^{-1}$. Under optimized conditions, the decolorization rate of A. XJ-2 was up to 94.8% in 48 h.