• Title/Summary/Keyword: OST

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Comparison of the Tribological behaviors of Various Organic Molecular Films (다양한 유기분자막의 마찰특성 비교)

  • ;;;V. Tsukruk
    • Tribology and Lubricants
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    • v.17 no.5
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    • pp.386-390
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    • 2001
  • Monolayers such as self-assembled monolayer (SAM) have received considerable attention to reduce stiction and friction in micro-devices and microelectromechanical systems (MEMS). Various organic molecular films were investigated to obtain better understanding of their tribological behaviors and adhesion property. The organic molecular films studied in this work are: epoxysilane SAMs, octadecyltricholosilane (OST), multi-layers composed of epoxysilane SAMs, poly[styrene-b-(ethylene-co-butylene)-b-styrene](SEBS) and compound of epoxy resin and poly (paraphenylene)(EP/PPP). The pull-off forces of these films were also obtained from force-distance curves measured in static mode of operation of atomic force microscope(AFM). Tribological tests were conducted with a ball-on-flat reciprocating friction tester. The OST showed the lowest pull-off force, indicating its low adhesion property. It was revealed that, the OST, EP/PPP and the multi-layer of epoxysilane SAMs, SEBS and EP/PPP exhibited good tribological properties at the lower load (0.3 N) whereas the OST showed best performance at the higher load (1.8 N).

Comparison of the tribological behaviors of various organic molecular films (다양한 유기분자막의 마찰특성 비교)

  • ;;;V. Tsukruk
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2001.06a
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    • pp.49-54
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    • 2001
  • Monolayers such as self-assembled monolayer (SAM) have received considerable attention to reduce stiction and friction in micro-devices and microelectromechanical systems (MEMS). Various organic molecular films were investigated to obtain better understanding of their tribological behaviors and adhesion property. The organic molecular films studied in this work are: epoxysilane SAMs, octadecyltricholosilane (OST), multi-layers composed of epoxysilane SAMs, poly〔styrene-b-(ethylene-co-butylene)-b-styrene〕(SEBS) and compound of epoxy resin and poly (paraphenylene) (EP/PPP). The pull-off forces of these films were also obtained from force-distance curves measured in static mode of operation of atomic force microscope (AFM). Tribological tests were conducted with a ball-on-flat reciprocating friction tester. The OST showed the lowest pull-off force, indicating its low adhesion property. It was revealed that, the OST, EP/PPP and the multi-layer of epoxysilane SAMs, SEBS and EP/PPP exhibited good tribological properties at the lower load (0.3 N) whereas the OST showed best performance at the higher load (1.8 N).

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Discovery of New Proteinase Inhibitor for the Treatment of Osteoporosis

  • 손문호
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2001.04a
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    • pp.89-99
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    • 2001
  • ■ Cathepsin K is a attractive target for selectively and efficiently modulating the osteoclastic bone resorption. ■ OST-1857 is a lead compound which is specifically targeted to cathepsin K and showed efficacy in TPTX rats. ■ OST-compounds are in process of the preclinical study, joined by Yuhan research center.

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Pandemics Era, A Study one the Viewers' Responses of Medical Drama through Text Mining. -Focused on - (팬데믹 시대, 텍스트 마이닝을 통한 의학드라마의 시청자 반응 연구-<슬기로운 의사생활>을 중심으로-)

  • Ahn, Sunghun;Oh, SeJong;Jeong, Dalyoung
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.4
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    • pp.385-389
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    • 2020
  • The medical drama has developed into a story centered on 'people', raising viewers' sympathy. The story of the drama is the true life story of doctors, patients and families. It is also a story that reminds me of 'a little special day of our ordinary people'. And the song played and sung by five characters in the drama became a factor that stimulates nostalgia and increases immersion. The highest viewer rating was 14.1%, and 51,584 blogs alone were registered. According to the big data analysis, the related words were 'Wise OST', 'Album Name', 'Artist Name', 'Two Hours in a row', 'Record', 'Remake', 'OST Revealed', 'Advertisement Revenue', 'Playlist', 'Aroha' and 'Cho Jung-seok'. The commercialization of medical dramas includes 'Sales of Drama OST Albums', 'Organizing Online Live Concerts (PPL in Advertising)', 'Publishing Piano Music', 'Picture of People-Oriented Photography', 'Making Music Video Editing Drama Highlight', 'YouTube Upload Profits', 'Mask' and 'Disinfectant'. it is predicted that the touching story of Corona 19 and the charming humanity will unfold. The limitations of the research will require analysis of various works by genre and attempts to analyze consumer values by industry.

Implementation of dynamic visual acuity testing system using optical see through head mounted display

  • Son, Hojun;Yun, Deokyoung;Kim, Jungho;Lee, Seunghyun;Kwon, Soonchul
    • International Journal of Internet, Broadcasting and Communication
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    • v.9 no.3
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    • pp.70-77
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    • 2017
  • Dynamic visual acuity is used as an important factor to measure athletic performance in sports field. A study on visual acuity testing system using non-see head mounted display (NST-HMD) was conducted recently. However, the NST-HMD has a problem that the sense of space felt by the subject differs from the actual environment. This is because the view is blocked so that it is only implemented in a virtual space. This paper proposes a dynamic visual acuity testing system using optical see through head mounted display (OST-HMD). To do this, OST-HMD and NST-HMD comparative tests were conducted using existing K-D (King-Devick) charts. Experiments were performed on 30 subjects and their visual acuity was measured and analyzed by parametric statistics and one-sample T-test. The results of the study demonstrate the effectiveness of the proposed OST-HMD. This study is expected to use the visual inspection and training equipment of OST-HMD.

A NEW AUTO-GUIDING SYSTEM FOR CQUEAN

  • CHOI, NAHYUN;PARK, WON-KEE;LEE, HYE-IN;JI, TAE-GEUN;JEON, YISEUL;IM, MYUNGSHI;PAK, SOOJONG
    • Journal of The Korean Astronomical Society
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    • v.48 no.3
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    • pp.177-185
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    • 2015
  • We develop a new auto-guiding system for the Camera for QUasars in the EArly uNiverse (CQUEAN). CQUEAN is an optical CCD camera system attached to the 2.1-m Otto-Struve Telescope (OST) at McDonald Observatory, USA. The new auto-guiding system differs from the original one in the following: instead of the cassegrain focus of the OST, it is attached to the finder scope; it has its own filter system for observation of bright targets; and it is controlled with the CQUEAN Auto-guiding Package, a newly developed auto-guiding program. Finder scope commands a very wide field of view at the expense of poorer light gathering power than that of the OST. Based on the star count data and the limiting magnitude of the system, we estimate there are more than 5.9 observable stars with a single FOV using the new auto-guiding CCD camera. An adapter is made to attach the system to the finder scope. The new auto-guiding system successfully guided the OST to obtain science data with CQUEAN during the test run in 2014 February. The FWHM and ellipticity distributions of stellar profiles on CQUEAN, images guided with the new auto-guiding system, indicate similar guiding capabilities with the original auto-guiding system but with slightly poorer guiding performance at longer exposures, as indicated by the position angle distribution. We conclude that the new auto-guiding system has overall similar guiding performance to the original system. The new auto-guiding system will be used for the second generation CQUEAN, but it can be used for other cassegrain instruments of the OST.

Method for Automatic Switching Screen of OST-HMD using Gaze Depth Estimation (시선 깊이 추정 기법을 이용한 OST-HMD 자동 스위칭 방법)

  • Lee, Youngho;Shin, Choonsung
    • Smart Media Journal
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    • v.7 no.1
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    • pp.31-36
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    • 2018
  • In this paper, we propose automatic screen on / off method of OST-HMD screen using gaze depth estimation technique. The proposed method uses MLP (Multi-layer Perceptron) to learn the user's gaze information and the corresponding distance of the object, and inputs the gaze information to estimate the distance. In the learning phase, eye-related features obtained using a wearable eye-tracker. These features are then entered into the Multi-layer Perceptron (MLP) for learning and model generation. In the inference step, eye - related features obtained from the eye tracker in real time input to the MLP to obtain the estimated depth value. Finally, we use the results of this calculation to determine whether to turn the display of the HMD on or off. A prototype was implemented and experiments were conducted to evaluate the feasibility of the proposed method.

A Study on the Comparison of the Library and Information Education System in Ost-and West Germany (동·서독의 사서·정보전문가 교육 비교 연구)

  • No, Mun-Ja
    • Journal of the Korean Society for information Management
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    • v.7 no.2
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    • pp.108-137
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    • 1990
  • The purpose of this paper is to compare the library and information education system in Ost-and West Germany. Toward this purpose, first, the historical beginning of library education is intraduced, secondly, library education system after the year of 1879 is descriebed along with theoretical foundation. Thirdly, seperated library education of the public librarian and academic librarian in Germany before and after the I. II World War was descirebed in context with historical and theoretical background and finnaly, in the modern information society. the library and information education of the seperated Ost-and West Germany is descriebed with their curricular.

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Principles of Space Resources Exploitation under International Law (국제법상 우주자원개발원칙)

  • Kim, Han-Teak
    • The Korean Journal of Air & Space Law and Policy
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    • v.33 no.2
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    • pp.35-59
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    • 2018
  • Professor Bin Cheng said that outer space was res extra commercium, while the moon and the other celestial bodies were res nullius before the 1967 Outer Space Treaty(OST). However, Article 2 of the OST made the moon and other celestial bodies have the legal status as res extra commmercium, not appropriated by any country or private enterprises or individual person, but the resources there can be freely available, as those on the high seas. The non-appropriation principle was introduced to corpus juris spatialis internationalis. Whether or not the non-appropriation principle is binding for the non-parties of the OST, many scholars see this principle as an international customary law, even developing into jus cogens. Article 11(2) of the Moon Agreement(MA) reconfirms the nonappropriation principle of Article 2 of the OST, but it has much less effect than the OST because the MA binds only the 18 parties involved. The MA applies only to the moon and celestial bodies other than the Earth in the Solar System, the OST's application scope extends to the Galaxy because the OST has no such substantive enactment. As referred to in the 2015 CSLCA of USA or Luxembourg's Law of Space Resources, allowing individuals and enterprises run by other countries to commercially explore and utilize the space resources, the question may arise whether this violates the non-appropriation principle under Article 2 of the OST and Article 11 of the MA. In the case of the CSLCA, the law explicitly specifies that sovereignty, possessory rights, and judiciary rights to a specific celestial body cannot be claimed, let alone ownership. This author believes that this law respects the legal status of outer space and the celestial bodies as res extra commmercium. As long as any countries or private enterprises or individuals respect the non-appropriation principle of outer space and the celestial bodies, they could use, exploit it. Another question might be raised in the difference between res extra commercium on the high seas and res extra commercium in outer space and the celestial bodies. Collecting resources on the high seas and exploiting space resources should be interpreted differently. On the high seas, resources can be collected without any obstacles like fishing, whereas, in the case of the deep sea-bed area, the Common Heritage of Mankind principles under the UNCLOS should be operated by the International Seabed Authority as an international regime. The nature or form of the sea resources found on the high seas are thus different from that of space resources, which are fixed on the moon and the celestial bodies without water. Thus, if individuals or private enterprises collect these resources from outer space and the celestial bodies, they might secure a certain section and continue collecting or mining works without any limitation. If an American enterprise receives an approval from the U.S. government, secures the best location and collects resources on the moon, can other countries' enterprises access to this area? How large the exploiting place can be allotted on the moon? How long should such a exploiting activity be lasted? Under the current international space law, these matters might be handled according to the principle of "first come, first served." As a consequence, the international community should provide a guideline or a proposal for the settlement of any foreseeable disputes during the space activity to solve plausible space legal questions in the near future.

Why Gabor Frames? Two Fundamental Measures of Coherence and Their Role in Model Selection

  • Bajwa, Waheed U.;Calderbank, Robert;Jafarpour, Sina
    • Journal of Communications and Networks
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    • v.12 no.4
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    • pp.289-307
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    • 2010
  • The problem of model selection arises in a number of contexts, such as subset selection in linear regression, estimation of structures in graphical models, and signal denoising. This paper studies non-asymptotic model selection for the general case of arbitrary (random or deterministic) design matrices and arbitrary nonzero entries of the signal. In this regard, it generalizes the notion of incoherence in the existing literature on model selection and introduces two fundamental measures of coherence-termed as the worst-case coherence and the average coherence-among the columns of a design matrix. It utilizes these two measures of coherence to provide an in-depth analysis of a simple, model-order agnostic one-step thresholding (OST) algorithm for model selection and proves that OST is feasible for exact as well as partial model selection as long as the design matrix obeys an easily verifiable property, which is termed as the coherence property. One of the key insights offered by the ensuing analysis in this regard is that OST can successfully carry out model selection even when methods based on convex optimization such as the lasso fail due to the rank deficiency of the submatrices of the design matrix. In addition, the paper establishes that if the design matrix has reasonably small worst-case and average coherence then OST performs near-optimally when either (i) the energy of any nonzero entry of the signal is close to the average signal energy per nonzero entry or (ii) the signal-to-noise ratio in the measurement system is not too high. Finally, two other key contributions of the paper are that (i) it provides bounds on the average coherence of Gaussian matrices and Gabor frames, and (ii) it extends the results on model selection using OST to low-complexity, model-order agnostic recovery of sparse signals with arbitrary nonzero entries. In particular, this part of the analysis in the paper implies that an Alltop Gabor frame together with OST can successfully carry out model selection and recovery of sparse signals irrespective of the phases of the nonzero entries even if the number of nonzero entries scales almost linearly with the number of rows of the Alltop Gabor frame.