• 제목/요약/키워드: HAS-2

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THE ARTINIAN COMPLETE INTERSECTION QUOTIENT AND THE STRONG LEFSCHETZ PROPERTY

  • Shin, Yong-Su
    • 충청수학회지
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    • 제32권2호
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    • pp.251-260
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    • 2019
  • It has been little known when an Artinian (point) quotient has the strong Lefschetz property. In this paper, we find the Artinian complete intersection quotient having the SLP. More precisely, we prove that if ${\mathbb{X}}$ is a complete intersection in ${\mathbb{P}}^2$ of type (2, 2) and ${\mathbb{Y}}$ is a finite set of points in ${\mathbb{P}}^2$ such that ${\mathbb{X}}{\cup}{\mathbb{Y}}$ is a basic configuration of type (2, a) with $a{\geq}3$ or (3, a) with a = 3, 4, 5, 6, then $R/(I_{\mathbb{X}}+I_{\mathbb{Y}})$ has the SLP. We also show that if ${\mathbb{X}}$ is a complete intersection in ${\mathbb{P}}^2$ of type (3, 2) and ${\mathbb{Y}}$ is a finite set of points in ${\mathbb{P}}^2$ such that ${\mathbb{X}}{\cup}{\mathbb{Y}}$ is a basic configuration of type (3, 3) or (3, 4), then $R/(I_{\mathbb{X}}+I_{\mathbb{Y}})$ has the SLP.

자동차 배기 매니폴드에 있어서의 열응력과 유동해석에 관한 연구 (Study on Thermal Stress and Flow Analysis at Exhaust Manifold of Car)

  • 조재웅;한문식
    • 한국자동차공학회논문집
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    • 제22권2호
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    • pp.23-28
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    • 2014
  • This study investigates fluid flow and thermal stress at automotive exhaust manifolds as model 1 and 2. The maximum displacements happen at joint part connected with 4 pipes and upper middle of both parts in cases of model 1 and 2 respectively. At inner surface of the part connected with engine, maximum equivalent stresses of 991.85 and 698.96 MPa are shown in cases of model 1 and 2 respectively. As maximum velocities at the outlet at model 1 are shown at 19.46 and 14.61 m/s in cases of model 1 and 2 respectively, model 1 has more pressure drop than model 2. As result, model 2 has less pressure drop than 1. Model 2 has less deformation and stress than model 1. Model 2 has also less pressure drop than model 1. Therefore model 2 has more strength durability than model 1. This study result is applied with the design of safe automotive manifold and it can be useful to improve the durability by predicting prevention against the deformation due to exhaust gas.

Monohydrogen Arsenate 감응 전극 (The Monohydrogen Arsenate-sensing Electrodes)

  • 인권식;박일배
    • 대한화학회지
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    • 제31권2호
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    • pp.162-167
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    • 1987
  • Monohydrogen arsenate를 전위차법으로 직접 정량하기 위하여 네가지 성분인 $Ag_2S$-PbS-$PbHAsO_4-Cu_2S$와 세가지 성분인 $Ag_2S$-PbS-$PbHAsO_4$로 된 전극이 제조되어 평가되었다. $Ag_2S$:PbS:$PbHAsO_4:Cu_2S$의 성분비(몰비)가 2.0:0.5:1.0:0.25인 전극이 전위차 감응, 안정도, 감응 속도와 재현성이 우수하였다. 0.1F $NH_4A_C-NH_4OH$ 완중용액 중의 일정한 이온 강도와 pH 8.50으로 조정된 $10^{-1}$~$10^{-4}M\;HA_SO_4^{2-}$ 농도 범위에서 실험하였고, $CN^-,\;I^-,\;S^{-2}$$Cl^-$등이 방해하였다.

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Synthesis and Characterization of Copper(Ⅱ) Complex Containing 2,2'-dipyridylbenzamide

  • 이동환;김병순;오영희;라명수;장원길
    • Bulletin of the Korean Chemical Society
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    • 제17권9호
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    • pp.836-839
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    • 1996
  • A new copper complex containing 2,2'-dipyridylbenzamide(dpba), Cu(dpba)(NO3)2(CH3CN), has been synthesized and characterized. The crystal structure has been determined. Crystal data: space group P212121, Z=8, a=13.911(3) Å, b=16.813(3) Å, c=18.932(3) Å, V=4427.9(1) Å3 and R=0.0674 for 1716 reflections. The copper environment is square pyramidal containing acetonitrile in axial site. Spectroscopic properties has been characterized in solution state. The redox property of the Cu(dpba)(NO3)2 complex is different from that of corresponding copper-dpa complex.

PBG 구조를 이용한 대역통과 여파기 고조파 억제에 관한 연구 (Harminic Suppression of Band Pass Filter Using Photonic Band Gap Structure)

  • 서철헌
    • 대한전자공학회논문지TC
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    • 제41권1호
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    • pp.69-72
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    • 2004
  • 접지면에 PBG와 Aperture를 설치함으로써 고성능 대역통과 여파기를 설계하였다. 대역통과 여파기의 하모닉 특성은 PBG 구조에 의하여 개선되었고 대역폭은 Aperture에 의하여 확대되었다. 세가지 크기를 갖는 PBG 구조가 결합되어 새로운 PBG 구조가 도출되었다. 설계 중심 주파수는 2.2 GHz이었고 대역폭은 Aperture에 의하여 $40\%$ 확대되었다.

혼합 모드 파괴 기준에서의 T응력의 영향에 관한 연구 (A Study on the Effect of T-Stress in the Mixed Mode Fracture Criterion)

  • 구재민;최태주
    • 한국안전학회지
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    • 제15권2호
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    • pp.13-21
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    • 2000
  • Under the mixed mode loading, it has been known that the influence of non-singular terms in the stress fields is serious, because the critical distance, ${\gamma}_o$ - the distance of nonlinear elastic region near the crack tip has no negligible value. In this paper, it has been studied on the influence of non-singular terms, T-stress, and the case of T=0, ${\sigma}cos^2{\beta}$, ${\sigma}cos(2{\beta})$ and $0.05{\sigma}cos(2{\beta})$, under uniaxial tension and compression. It has been seen that the T-stress of ${\sigma}cos(2{\beta})$ has better than others as comparing to the experimental data.

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전파흡수체용 $[Ni_x-Mg_{0.1}-Zn_{(1-x-0.1)}{\cdot}Fe_2O_4]$-Rubber Composite에 관한 연구 (A Study on $[Ni_x-Mg_{0.1}-Zn_{(1-x-0.1)}{\cdot}Fe_2O_4]$-Rubber Composite for Electromagnetic Wave Absorber)

  • 박연준;김동일
    • 한국항해학회지
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    • 제22권4호
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    • pp.69-75
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    • 1998
  • The super wideband electromagnetic wave absorber in RF-A-PF type has been proposed, which can be used for an anechoic chamber, wall material to prevent TV ghost, etc, In this paper, $Ni_x-Mg_{0.1}-Zn_(1-x-0.1){\cdot}Fe_2O_4$ Ferrite Powder has been fabricated. Using this, then, [$Ni_x-Mg_{0.1}-Zn_(1-x-0.1){\cdot}Fe_2O_4$-Rubber composite for RF-layer in the RF-A-PF type absorber has been fabricated and its characteristics has been analyzed. As a result, it has been shown that the $Ni_x-Mg_{0.1}-Zn_(1-x-0.1){\cdot}Fe_2O_4$-Rubber composit with the quantity $_x$ of $Ni_x$ between 0.5 and 0.6 is suitable for the RF-layer in the case of which the grain size is sub-micrometer order.

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O2O서비스의 지속이용의도에 영향을 미치는 요인에 관한 연구 : 영화관 티켓 발권서비스를 중심으로 (A Study on Factors Affecting Intention to Continuous Use of O2O Service : Focused on Cinema Ticketing Systems)

  • 박소은;이성혜;지대범;최정일
    • 한국IT서비스학회지
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    • 제16권4호
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    • pp.197-212
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    • 2017
  • This study aims to investigate factors affecting the intention of continuous use of O2O service by referring new media adoption theory and value-based acceptance model for movie ticketing services. For this study, a questionnaire survey was conducted for users of tickets ticketing service of the cinema online (including mobile) within the last 6 months. A total of 500 copies was collected and 404 copies were analyzed excluding 96 copies because of errors. As a result of the analysis, the ease of use and service ubiquity has a positive effect on perceived functional value and perceived emotional value, and usability has a positive effect on perceived functional value. Compatibility and trialability has a positive effect on both perceived functional value and emotional value. Previous experience has a positive effect on both perceived functional value and perceived emotional value, and inertia has negative effect on perceived functional value. Finally, the perceived emotional value has a positive effect on the intention to continuous use, but perceived functional value appeared to have no significant effect. This study shows a theoretical implication for new technology-based services such O2O. It was suggested to establish a practical marketing strategy and help to activate the O2O service field.

홍삼약침액(紅蔘藥鍼液)의 위암세포주(胃癌細胞柱) 유전자(遺傳子) 발현(發顯)에 미치는 영향(影響) (Effect of Ginseng Radix Rubra Herbal-acupuncture Solution(GRR-HAS) on Gene Expression in SNU484 carcinomar cells)

  • 원은주;이경민;이봉효;임성철;정태영;서정철
    • 대한약침학회지
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    • 제9권2호
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    • pp.39-47
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    • 2006
  • Objective : It has long been known about the anticancer effect of GRR-HAS, however, it has not been systemically determined the differentially regulated genes by GRR-HAS in cancer cells. The purpose of this study is to screen the GRR-HAS mediated differentially expressed genes in cancer cells such as SNU484 gastric cancer cell lines. Oligonucleotide microarray approache was employed to screen the differential expression genes. Methods : GRR-HAS was prepared by boiling and stored at $-70^{\circ}C$ until use. Cells were treated with various concentrations of GRR-HAS(0.1, 0.5, 1.5, 10, 20mg/ml) for 24 h. Cell toxicity was tested by MTT assay. To screen the differentially expressed genes in cancer cells, cells were treated with 1.5mg/ml of GRR-HAS. For oligonucleotide microarray assay, total RNA was used for gene expression analysis using oligonucleotide Genechip (Human genome Ul33 Plus 2.0., Affimatrix Co.). Results : It has no cytotoxic effects on both HepG2 and SNU484 cells in all concentrations(0.1, 0.5, 1.5, 10, 20mg/ml). In oligonucleotide microarray assay, in SNU484 cells, the number of more than twofold up-regulated genes was 346. The number of more than twofold down-regulated genes was 9. Discussion : This study showed the comprehensive gene expression analysis using oligonucleotide microarray for the screening of GRR-HAS mediated differentially regulated genes. These results will provide a better application of GRR-HAS in cancer field and drug target development.

The developments of heavy hydrocarbon reformer for SOFC

  • 배중면
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2012년도 춘계학술발표대회
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    • pp.58.2-58.2
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    • 2012
  • Heavy hydrocarbon reforming is a core technology for "Dirty energy smart". Heavy hydrocarbons are components of fossil fuels, biomass, coke oven gas and etc. Heavy hydrocarbon reforming converts the fuels into $H_2$-rich syngas. And then $H_2$-rich syngas is used for the production of electricity, synthetic fuels and petrochemicals. Energy can be used efficiently and obtained from various sources by using $H_2$-rich syngas from heavy hydrocarbon reforming. Especially, the key point of "Dirty energy smart" is using "dirty fuel" which is wasted in an inefficient way. New energy conversion laboratory of KAIST has been researched diesel reforming for solid oxide fuel cell (SOFC) as a part of "Dirty energy smart". Diesel is heavy hydrocarbon fuels which has higher carbon number than natural gas, kerosene and gasoline. Diesel reforming has difficulties due to the evaporation of fuels and coke formation. Nevertheless, diesel reforming technology is directly applied to "Dirty fuel" because diesel has the similar chemical properties with "Dirty fuel". On the other hand, SOFC has advantages on high efficiency and wasted heat recovery. Nippon oil Co. of Japan recently commercializes 700We class SOFC system using city gas. Considering the market situation, the development of diesel reformer has a great ripple effect. SOFC system can be applied to auxiliary power unit and distributed power generation. In addition, "Dirty energy smart" can be realized by applying diesel reforming technology to "Dirty fuel". As well as material developments, multidirectional approaches are required to reform heavy hydrocarbon fuels and use $H_2$-rich gas in SOFC. Gd doped ceria (CGO, $Ce_{1-x}Gd_xO_{2-y}$) has been researched for not only electrolyte materials but also catalysts supports. In addition, catalysts infiltrated electrode over porous $La_{0.8}Sr_{0.2}Ga_{0.8}Mg_{0.2}O_3-{\delta}$ and catalyst deposition at three phase boundary are being investigated to improve the performance of SOFC. On the other hand, nozzle for diesel atomization and post-reforming for light-hydrocarbons removal are examples of solving material problems in multidirectional approaches. Likewise, multidirectional approaches are necessary to realize "Dirty energy smart" like reforming "Dirty fuel" for SOFC.

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