• Title/Summary/Keyword: Ar

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Refining of Steels by $Ar-CO_2$ Plasma (Ar-CO$_2$ Plasma에 의한 강(鋼)의 정련(精鍊))

  • Chang, Sek-Young;Kim, Dong-Ui
    • Journal of Korea Foundry Society
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    • v.6 no.4
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    • pp.284-289
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    • 1986
  • Decarburization phenomena have been studied by plasma in stainless steel, plain carbon steel and cast iron. It was also investigated the movement of impurity element P,S in the plasma jet metal pool. The plasma jet was obtained by $Ar\;-\;CO_2$ gas mixture with 5 kVA DC power source. It produced enough temperature to dissociate into activated oxygen atom by reaction of $CO_2{\leftrightarrows}CO+O^+$ and it reacted with ${\underline{C}}$ in metal pool. Decarburization rate was increased about 5 times in comparing with the conventional induction melted metal pool by $CO_2$ gas decarburization. Even under the Ar plasma jet, decarburization was obtained by agitation of metal bath by $Ar^+$ bombardment and dilution phenomena of carbon atom under the very high plasma temperature. But heavy element P and S are not much removed because they are too heavy in mass to be activated by $Ar^+$ion bombardment. Desulphurization was achieved by $Ar\;-\;CO_2$ plasma in plain carbon steel and cast iron by the reaction of $SO_2({\underline{S}}+O^+)$. But dephosphorization could not be obtained by $Ar\;-\;CO_2$ plasma, because gaseous reaction of phosphorous oxide (${\underline{P}}+O^+$) was not existed.

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Impact Factors Analysis on AR Shopping Service's Immersion

  • SHIN, Myoung-Ho;LEE, Young-Min;KIM, Jin-Hwan
    • Journal of Distribution Science
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    • v.17 no.12
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    • pp.13-21
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    • 2019
  • Purpose - It is very important to examine customer's behavior about AR shopping either practically or academically. Thus, it will be worthwhile to discuss more in details about AR utility which is even in early stage of distribution industry now. Research design, data, and methodology - This study has designed in consideration of control effects of perceived complexity based on customer's flow as dependent variable, and on AR characteristics and technology readiness as independent variables. Study data has been collected from questionnaires after using AR shopping service directly by those who are 20-30 years old of male and female respondents, which has been analyzed with 167 questionnaires. Hypothesis is verified using by hierarchical regression analysis. Results - After results of hypothesis verified, positive influence has been shown in terms of sensory immersion, manipulation, and optimism, however, it is rejected in relation to navigation and innovativeness. Control effect of perceived complexity has not been appeared. Conclusions - Implications of this study are as follows. First, AR shopping service has to provide an informational value. Second, by providing AR service to customer group, marketing activities will be in effects. Third, recognized complexity is not connected with significant control effect in terms of customer's devotion of service.

Dynamic Manipulation of a Virtual Object in Marker-less AR system Based on Both Human Hands

  • Chun, Jun-Chul;Lee, Byung-Sung
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.4
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    • pp.618-632
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    • 2010
  • This paper presents a novel approach to control the augmented reality (AR) objects robustly in a marker-less AR system by fingertip tracking and hand pattern recognition. It is known that one of the promising ways to develop a marker-less AR system is using human's body such as hand or face for replacing traditional fiducial markers. This paper introduces a real-time method to manipulate the overlaid virtual objects dynamically in a marker-less AR system using both hands with a single camera. The left bare hand is considered as a virtual marker in the marker-less AR system and the right hand is used as a hand mouse. To build the marker-less system, we utilize a skin-color model for hand shape detection and curvature-based fingertip detection from an input video image. Using the detected fingertips the camera pose are estimated to overlay virtual objects on the hand coordinate system. In order to manipulate the virtual objects rendered on the marker-less AR system dynamically, a vision-based hand control interface, which exploits the fingertip tracking for the movement of the objects and pattern matching for the hand command initiation, is developed. From the experiments, we can prove that the proposed and developed system can control the objects dynamically in a convenient fashion.

Tissue- and maturity-dependent expression pattern of androgen receptor mRNA in goldfish, Carassius auratus

  • Choi, Cheol-Young;Kim, Soon-Hag;Kim, Bong-Seok
    • Journal of fish pathology
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    • v.16 no.2
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    • pp.111-118
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    • 2003
  • Androgen plays an important role in the regulation of gonadotropin production in vertebrates . We have investigated the transcriptional pattern of androgen receptor (AR) in a variety of tissues in maturing male and female goldfish by RT-PCR. Specific primer for AR was designed based on goldfish AR gene from the GenBank (accession number AY090897). AR was shown 10 be maturity- and tissue-dependent gene expression pattern in goldfish. In immature male goldfish, significantly higher transcript level of AR was observed in the pituitary und testis , compared [0 brain and liver. Mature male goldfish showed a similar expression pattern to immature male goldfish. Interestingly. when compare to male goldfish, female goldfish showed AR mRNA expression that was found 10 be weak in pituitary, and very low expression in brain. They could not be found 10 have expression in any other tissues. Taken together. the- transcriptional analysis of AR depending on the tissue, sex. and maturity of a goldfish provides the opportunity for the study of goldfish reproductive physiology ,The results provided for the first time a comparison of the tissue distribution of AR mRNA in sexually maturating male and female goldfish.

Polyethersulfone 기판 위에 증착된 GaZnO 투명전도성 박막의 특성

  • Go, Ji-Hyeon;Jeong, Ui-Wan;Lee, Jin-Yong;Lee, Yeong-Min;Kim, Deuk-Yeong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.80-80
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    • 2011
  • 본 연구에서는 flexible 광전소자에 응용이 가능한 투명전극을 위해 polyethersulfone (PES) 기판 위에 GaZnO (GZO) 박막을 마그네트론 스퍼터 법으로 증착하였다. 박막 증착 중 Ar 분압의 변화가 박막의 특성에 미치는 영향을 분석하기 위해, 스퍼터 반응시 chamber내 Ar 분압을 10 sccm~50 sccm 범위에서 변화를 주었다. 박막이 증착된 후 GZO/PES 시료의 광학적 투과율을 측정한 결과 가시광 영역에서 80% 이상의 높은 투과율을 보이고 있었다. 이때 광학적 투과율은 Ar 분압의 변화에는 영향을 받고 있지 않은 것으로 분석되었다. 시료의 표면을 주사전자현미경 분광법으로 분석한 결과 Ar 분압이 증가 할수록 GZO grain 크기가 감소하여 그 조밀도가 증가하는 경향을 나타내었다. 또한 x-ray 회절 스펙트럼에서는 ZnO (002) peak의 세기가 증가함을 확인하였고, 이에 반하여 $ZnGa_2O_4$의 (311) peak의 세기는 감소하는 경향을 확인할 수 있었다. 한편 제작된 시료의 전기적 특성을 분석한 결과 Ar 분압의 증가에 따라 비저항이 약 $7.5{\times}10^{-3}{\Omega}cm$ 까지 감소하는 경향을 보였다. 이는 Ar 분압이 증가할수록 Ar-plasma enhancement 효과로 GZO의 결정학적 특성이 향상되면서 GZO의 전기전도 특성을 저해 하는 insulating $ZnGa_2O_4phase$의 형성을 억제하였기 때문인 것으로 해석된다.

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Ar 유량 변화에 따라 RF Magnetron Sputterin 법으로 제조된 GZO 박막의 특성변화

  • Jeong, Seong-Jin;Kim, Deok-Gyu;Kim, Hong-Bae
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.232-232
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    • 2011
  • 투명전도산화물에 대한 연구가 많이 이루어지고 있으며, 최근 Ga이 도핑된 ZnO의 연구가 많이 되고 있다. 투명전도산화물은 태양전지, 평면디스플레이와 같은 다양한 분야에 응용이 가능하다. 본 연구에서는 RF magnetron sputtering을 이용하여 Ar gas 유량 변화에 따른 GZO 박막을 연구하였다. 기판으로는 유리기판을 사용하였으며, 전기적, 광학적, 구조적인 특성을 조사하였다. 박막의 증착시 초기 압력은 $2.0{\times}10^{-6}$Torr 이하로 하였으며, 증착온도는 상온으로 고정하여 증착하였다. 기판은 Corning 1737 유리 기판을 사용하였고, GZO 타겟은 ZnO : Ga 분말이 각각 97 : 3 wt.%로 소결된 타겟을 사용하였다. Ar 유량변수는 20, 40, 60, 80 sccm으로 변화를 주었다. 유리기판에 증착된 모든 GZO박막은 약 200 nm의 두께로 증착되었으며 모든 GZO 박막에서 85%이상의 투과율을 나타내었다. Ar 유량이 적을수록 투과율을 증가하였으며, 광학적 밴드갭 또한 증가하였다. 공정별로 제작된 모든 GZO박막에서 (002)면의 배향성이 관찰되었고, Ar 유량이 적을수록 박막의 결정성은 향상되었다. Hall 측정 결과 Ar 유량이 20 sccm일 때 전기비저항 $3.46{\times}10^{-3}{\Omega}cm$, 전하의 농도 $3.832{\times}10^{-20}\;cm^{-3}$, 이동도 $4.7cm^2V^{-1}s^{-1}$로 전극으로서의 특성을 나타내었다. GZO 박막의 경우 Ar 유량이 적었을 때 결정성이 높아지고, 전극 특성이 더 우수한 것을 확인할 수 있었다.

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Adenophorae Radix Attenuates Mast Cell-mediated Allergic Inflammation through Down-regulation of NF-κB/ Caspase-1 Activation

  • Myung, Noh-Yil
    • Korean Journal of Plant Resources
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    • v.33 no.6
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    • pp.659-665
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    • 2020
  • Adenophorae Radix (AR) has been used as a traditional medicine for various diseases. However, the regulatory mechanisms of AR in allergic inflammation are not yet understood. The present study was conducted to investigate the effect and mechanisms of AR on the mast cell-mediated allergic response. To determine the pharmacological mechanisms of AR in allergic inflammation, we evaluated the effects of AR on the production of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β and IL-8 as well as the activation of nuclear factor-κB (NF-κB) and caspase-1 in phorbol 12-myristate 13-acetate plus calcium ionophore A23187 (PMACI)-stimulated human mast cells (HMC-1). Our results demonstrated that AR effectively attenuated the PMACI-induced production of TNF-α, IL-6, IL-1β and IL-8 in stimulated HMC-1. Additionally, we showed that the inhibitory effect of AR on inflammatory cytokines in PMACI-stimulated HMC-1 cells involved the suppression of the activation NF-kB/caspase-1 in PMACI-stimulated HMC-1. Collectively, these findings provide experimental evidence that AR may be a useful candidate for the treatment of allergic inflammation.

A study on etching mechanism of SBT thin flim by using Ar/$CHF_3$plasma (Ar/$CHF_34$플라즈마를 이용한 SBT 박막에 대한 식각 메카니즘 연구)

  • 서정우;장의구;김창일;이원재;유병곤
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.3
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    • pp.183-187
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    • 2000
  • In this study the SrBi$_2$Ta$_2$$O_{9}$ (SBT) thin films were etched by using magnetically enhanced inductively coupled Ar/CHF$_3$plasma as function of CHF$_3$/(Ar+CHF$_3$)gas mixing ratio. Maximum etch rate of SBT thin films was 1650 $\AA$/min and the selectivities of SBT to Pt and photoresist(PR) were 1.35 and 0.94 respectively under CHF$_3$/(Ar+CHF$_3$) of 0.1 For study on etching mechanism of SBT thin film X-ray photoelectron spectroscopy (XPS) surface analyses and secondary ion mass spectrometry (SIMS) mass analysis of etched SBT surfaces were performed. Among the elements of SBT thin film. M(Sr, Bi, Ta)-O bonds are broken by Ar ion bombardment and form SrF and TaF$_2$by chemical reaction with F. SrF and TaF$_2$are removed more easily by Ar ion bombardment. Scanning electron microscopy(SEM) was used for the profile examination of etched SBT film and the cross-sectional SEM profile of etched SBT film under CHF$_3$(Ar+CHF$_3$) of 0.1 was about 85$^{\circ}$X>.

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The Study on the surface of SBT Thin Film after Etching in Ar/$CI_2$ Plasma (Ar/$CI_2$ 식각 후 SBT 박막의 표면에 관한 연구)

  • 김동표;김창일;이원재;유병곤;김태형;장의구
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.11a
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    • pp.363-366
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    • 2000
  • In this study, SrBi$_2$Ta$_2$$O_{9}$ (SBT) thin films were etched at different Cl$_2$gas mixing ratio in Cl$_2$/Ar. The maximum etch rate of SBT was 883 $\AA$/min in Cl$_2$(20%)/Ar(80%). The result indicates that physical sputtering of charged particles is dominant to chemical reaction in etching SBT thin films. To evaluate the changes of morphology and crystallinity on the near surface of etched SBT, atomic force microscopy (AFM) and x-ray diffraction (XRD) were used. The rms values of etched samples in Ar only or Cl$_2$ only plasma were higher than that of as-deposited, Cl$_2$/Ar Plasma. The SBT (105) crystalinity of the etched samples decreased in Af only or Cla only plasma, but maintain constant in ClyAr plasma. This can be illustrated by a decrease of Bi content or nonvolatile etching products (Sr-Cl and Ta-Cl), resulting in the changes of stoichiometry on the etched surface of the SBT thin films. The decrease of Bi content and nonvolatile etch products were revealed by x-ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS).).

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Insulin-Like Growth Factor-I-Induced Androgen Receptor Activation Is Mediated by the PI3K/Akt Pathway in C2C12 Skeletal Muscle Cells

  • Lee, Won Jun
    • Molecules and Cells
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    • v.28 no.5
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    • pp.495-499
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    • 2009
  • Although insulin-like growth factor-I (IGF-I) and androgen receptor (AR) are well known effectors of skeletal muscle, the molecular mechanism by which signaling pathways integrating AR and IGF-I in skeletal muscle cells has not been previously examined. In this study, the role of PI3K/Akt on IGF-I-induced gene expression and activation of AR in skeletal muscle cells was investigated. C2C12 cells were treated with IGF-I in the absence or presence of inhibitors of PI3K/Akt pathway (LY294002 and Wortmannin). Inhibition of the PI3K/Akt pathway with LY294002 or Wortmannin led to a significant decrease in IGF-I-induced AR phosphorylation and total AR protein expression. Furthermore, IGF-I-induced AR mRNA and skeletal ${\alpha}-actin$ mRNA were blocked by LY294002 or Wortmannin. Confocal images showed that IGF-I-induced AR translocation from cytosol to nucleus was inhibited significantly in response to treatment with LY294002 or Wortmannin. The present results suggest that modulating effect of IGF-I on AR gene expression and activation in C2C12 mouse skeletal muscle cells is mediated at least in part by the PI3K/Akt pathway.