• Title/Summary/Keyword: NII

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An observed link between AGN Eddington ratio and [NII] λ6583/Hα at 0.6

  • Oh, Kyuseok;Ueda, Yoshihiro;Akiyama, Masayuki;Suh, Hyewon;Koss, Michael;Mushotzky, Richard;Hasinger, Guenther;Kashino, Daichi;Silverman, John
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.36.1-36.1
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    • 2019
  • We present the observed relationship between Eddington ratio (${\lambda}Edd$) and optical narrow-emission-line ratio ([NII] ${\lambda}6583/H{\alpha}$) of X-ray-selected unobscured active galactic nuclei (AGN) at 0.6 < z < 1.7 using 27 near-infrared spectra from the Fiber Multi-Object Spectrograph mounted on the Subaru telescope along with 26 additional sources from the literature. We show that the ${\lambda}Edd$ and [NII] ${\lambda}6583/H{\alpha}$ ratio at 0.6 < z < 1.7 exhibits a similar distribution of ${\lambda}Edd$-[NII] ${\lambda}6583/H{\alpha}$ anti-correlation that has been found for local ( = 0.036), hard X-ray selected AGN. The observed anti-correlation suggests that [N II] ${\lambda}6583/H{\alpha}$ optical narrow-line ratio in the AGN host galaxy may carry important information about the accretion state of the central supermassive black hole, suggesting the observational hint of consistent relationship from local to z ~ 1.7. Further study is necessary to determine whether the ${\lambda}Edd$-[N II] ${\lambda}6583/H{\alpha}$ correlation in high-redshift still holds at ${\log}{\lambda}Edd$ < -2 compared to local AGN.

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PHOTOMETRY AND SPECTROSCOPY OF THE SPIRAL GALAXY NGC7678

  • ANN HONG-BAE;KIM JEONG-MI
    • Journal of The Korean Astronomical Society
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    • v.29 no.2
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    • pp.255-268
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    • 1996
  • We present VR CCD photometry and long-slit spectroscopy of a late type spiral galaxy NGC 7678. The grey scale images and isophotal maps illustrate the presence of a weak bar from which spiral arms emerge. There are many HII regions along the spiral arms, but bright giant HII regions are more concentrated in the massive southern arm. The bright compact nucleus of NGC 7678 is bluer than bulge and bar. The spectral features of the nucleus and HII regoins are very similar but the nuclear spectra shows higher $[NII]{\lambda}6583/H_\alpha$ than those of the HII regions. The nucleus of NGC 7678 seems to be intermediate type between HII region nulcei and LINERs by the ratio of $[NII]{\lambda}6583/H_\alpha$, but it is more likely to be HII region-like nucleus if we consider the $[NII]{\lambda}6716,6731/H_\alpha$ together. The star formation rate is estimated to be about $0.2 M_\bigodot\;yr^{-1}$ based on the $H_\alpha$ flux.

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미국의 정보고속도로(Information Superhighway) 구상과 통신사업자의 동향(I)

  • 김경돈
    • TTA Journal
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    • s.35
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    • pp.19-35
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    • 1994
  • 미국에서는 정보통신분야를 미래의 성장잠재력이 가장 큰 분야라고 보고 그 하부구조인 NII(National Information Infrastructure)로서 정보고속도로(Information Superhighway)를 건설하려고 한다. 고어부통령이 앞장서 제창하고 민간부문이 뒷받침하고 있는 이 구상은 고어자신이 부에노스아이레스에서 열린 세계전기통신개발회의(WDTC) 연설에서 밝힌 GII(Global Information Infrastructure)계획과 같이 앞으로 미국뿐만 아니라 전세계적으로도 현안 과제가 될 것이라고 생각된다. 따라서 민간부문을 중심으로 추진되어야 한다는 원칙을 표방하고 있는 미국의 NII구상을 살펴봄으로써 우리나라에서 추진될 초고속통신망의 모습을 미리 그려보는데 도움을 얻고자 한다.

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미국의 정보고속도로(Information Superhighway)구상과 통신사업자의 동향(II)

  • 김경돈
    • TTA Journal
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    • s.36
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    • pp.13-32
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    • 1994
  • 미국에서는 정보통신분야를 미래의 성장잠재력이 가장 큰 분야라고 보고 그 하부구조인 NII(National Information Infrastructure)로서 정보고속도로(Information Superhighway)를 건설하려고 한다. 고어부통령이 앞장서 제창하고 민간부문이 뒷받침하고 있는 이 구상은 고어자신이 부에노스아이레스에서 열린 세계전기통신개발회의(WDTC) 연설에서 밝힌 GII(Global Information Infrastructure)계획과 같이 앞으로 미국뿐만 아니라 전세계적으로도 현안 과제가 될 것이라고 생각된다. 따라서 민간부문을 중심으로 추진되어야 한다는 원칙을 표방하고 있는 미국의 NII구상을 살펴봄으로써 우리나라에서 추진될 초고속통신망의 모습을 미리 그려보는데 도움을 얻고자 한다.

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A Study on Direction of Next Generation Bibliographic Network (차세대 서지네트워크의 방향성 모색)

  • Cho, Jane
    • Journal of Korean Library and Information Science Society
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    • v.42 no.2
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    • pp.85-103
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    • 2011
  • Bibliographic Network has been a goal about not only to support resource sharing within libraries but also to pursue economic efficiency of cataloging. But nowadays, as resources in diverse media and format have been poured out, printed resources based union catalog should change to new resources finding system which include diverse type of resources. This study analyzes changing factors of bibliographic network and strategies for LC, NII, OCLC, NLA who try to turn over a new service. Finally basis on these findings, suggest task for Korean new generation bibliographic network service which is focused on introducing new collaborating model and developing new resource finding system.

LOW NOISE AMPLIFIER USING ELECTROMAGNETIC SIMULATOR AT U-NII FREQUENCY BAND

  • Kim, Hak-Sung;Kim, Cheol-Su;Kim, Cheol-Su;Lee, Byung-Jae;Lee, Jong-Chul;Kim, Nam-Young
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2000.11a
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    • pp.225-228
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    • 2000
  • In this paper, the design for a low noise amplifier with the EM simulation is presented. The ATF36077 pHEMT device is applied to design LNA for U-NII frequency band (5 GHz ~ 6 GHz). The matching networks have been designed by the only open ended stub in order to reduce parasitic effects generated from a via structure. Through EM simulator, the simulation result shows that the linear gain (@5.5 GHz) is over 10 dB, input return loss and output return loss (@ 5.5 GHz) are a below 10 dB respectively, and the 3rd order intercept point is about 17 dBm.

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A Comparative Study of Academic Resource Sharing and Service System Between Korea and Japan (한국과 일본의 대학 학술정보 공유 유통 체계 비교 연구)

  • Cho, Jane
    • Journal of Korean Library and Information Science Society
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    • v.43 no.4
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    • pp.23-45
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    • 2012
  • From 1990s the Ministry of Education and KERIS have developed nationwide academic resource sharing and service system based on universities, and have contributed to bridge the gap of information and to facilitate resource sharing between universities. Meanwhile, in Japan which starts 15 years earlier than us, the Ministry of Education and NII built nationwide academic resource sharing and service system with starting on the project of university holding resource sharing and until now have shown similar aspect of development like us. But lately, since information environment has been changing rapidly, Japan try to find new paradigm which goes around electronic resources management substitute for physical resources and open access based academic communication, institutional repository which disseminate university's research output to the outside world. This study compare academic resource sharing and service system between Japan and Korea and try to suggest for Korean academic resource sharing and service system development. In Korea, firstly we should try to replacing published resources management system to electronic resources', secondly, reorganizing oversea's resource sharing and service system, thirdly, reactivating institutional repository toward open access, finally, unification of distracted driving force.

The Design Development of Easy Casual Wear for Career Women (직장여성을 위한 이지 캐주얼 웨어 디자인 개발)

  • Byun, Mi-Yeon;Lee, In-Seong
    • Journal of the Korean Society of Clothing and Textiles
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    • v.30 no.8
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    • pp.1301-1311
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    • 2006
  • This study rearranged a concept of Friday wear considered as casual wear by searching social background through analysis of literature study and photo materials and classifying by characteristics of casual wear. It investigated growing changes of casual wear and the progress of changes casual brands through a market survey based on departments in Seoul. And then, it examined characteristics of a design and the critical point of easy casual selecting GIORDANO, TBJ and NII of three easy casual brands. Conclusions of the study are as follows: Firstly, present casual wear showed subdivision of casual wear as abundant grouping vocabularies appeared contrary to the past. Secondly, easy casual wear has continuously increased by results of investigating departments in Seoul on the progress of changing easy casual wear brand including the concept of Friday wear. Thirdly, if a main target sets the early 20s, women workers in their 20's and 30's are likely to be reluctant to wear it according to results of investigating designs and characteristics based on GIORDANO, TBJ and NII of existing three easy casual brands through the market survey. Also, it was verified that most of these brands have no a luxurious image because they adhere to middle-low price. Fourthly, it improved problems of easy casual through developing designs of easy casual wear. Easy casual wear supplementing weak these points of easy casual wear was evaluated as suitable clothes for workers to wear in on and off their own time in Friday.