• 제목/요약/키워드: Hand positions

검색결과 243건 처리시간 0.025초

Near-infrared Spectroscopy of Iron Knots in Cassiopeia A Supernova Remnant

  • Lee, Yong-Hyun;Koo, Bon-Chul;Moon, Dae-Sik
    • 천문학회보
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    • 제35권2호
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    • pp.68.1-68.1
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    • 2010
  • Cassiopeia A supernova remnant is a young (~330 yr) remnant of Type IIb SN explosion with a massive progenitor. It shows two distinct optical knots; fast moving ejecta knots (FMKs) and quasi stationary circumstellar knots (QSFs). These knots offer an unique opportunity to explore the details of the explosion and also the end state evolution of the Type IIb SN progenitor. We have obtained NIR long-slit (30") spectra of 7 positions around the bright rim of Cas A in [Fe II] 1.644 micron using Triplespec which is a cross-dispersed near-infrared spectrograph that provides continuous wavelength coverage from 0.95-2.46um at intermediate resolution of 2700. Most of the FMKs show strong sulfur, silicon, and iron forbidden lines but no hydrogen or helium lines. The QSFs, on the other hand, show a much richer spectrum with strong hydrogen, helium, and iron lines, but no sulfur and silicon lines. We measure their fluxes and radial velocities, and derive their physical parameters such as electron density and temperature. We also measure the proper motion of these knots from two [Fe II] 1.644 micron images obtained at 3-year interval. We analyze the physical properties of these knots and discuss the evolution and explosion of the progenitor of Cas A.

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Social Dimensions of Peer Interaction: Primary School Children Working with English Learning Software

  • Park, Heekyong
    • 한국영어학회지:영어학
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    • 제3권3호
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    • pp.453-497
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    • 2003
  • The purpose of this study is to investigate social aspects of young EFL learners' interaction at the computer. Data were taken from the interactions of three pairs of fourth-grade primary school children who worked together on English learning software. Their interactions at the computer were videotaped and then all the talk produced by the students and the utterances emitted from the computer were transcribed. As for the analytical tools, the notion of ‘contextualization cues’ (Gumperz, 1982) and the concept of ‘positioning’ (Davies & Harre,1990) were employed. The analysis reveals that the roles of the students were not tied to a certain position, but rather dynamically changed during the course of interactive work according to the situation at hand. The dynamic changes in their positions were realized through various means; their capability in solving problems, their taking responsibility or assigning it to each other, or cooperation. There were also instances of peer teaching and motivated learning. In addition, the students showed autonomy in their learning activity. These findings suggest that both students in a dyad had their own place in performing task activities, contributing to solving problems and getting benefits from peer interaction. Furthermore, students' working together on English learning software may provide an environment which can promote cooperative attitude and responsibility for learning and enhance motivation and autonomy in their learning process.

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드래그 및 방향전환 동작 기반의 상대좌표형 터치 유저 인터페이스 (Touch User Interface of Relative Coordinate Style based on Drag and Diversion Operations)

  • 백정훈;최경순
    • 한국정보통신학회논문지
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    • 제15권1호
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    • pp.89-98
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    • 2011
  • 본 논문에서는 휴대폰이나 TV 등의 터치화면에 한 번의 터치와 터치된 상태에서의 드래그(drag) 및 방향전환 동작만으로 문자를 용이하게 입력할 수 있고, 다층 구조 메뉴를 신속하고 편리하게 검색 및 선택할 수 있는 새로운 터치 유저 인터페이스 방식을 제안한다. 또한, 터치면의 고정된 위치에 고정된 문자를 할당함으로서 한정된 크기의 터치 면에 여러 문자를 중복할당 할 수 밖에 없는 기존의 절대좌표 방식의 한계성을 극복하기 위하여 터치 위치 이동에 따라 상대좌표를 도출하고 상대좌표에 대응되는 문자를 표시함으로서 한정된 터치영역에서 더 많은 문자를 수용할 수 있는 상대좌표 기반의 문자 할당 및 입력방식을 제안한다. 제안된 방식은 IPTV 플랫폼의 리모컨과 셋톱박스로 구현되어 제안 방식의 실용성과 유효성을 입증한다.

단말기 동작인식과 상호 통신을 결합한 스마트폰 게임의 구현 (Implementation of Smartphone Games Combining Motion Recognitions and Mutual Communications of Terminals)

  • 이숭희
    • 한국정보통신학회논문지
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    • 제16권9호
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    • pp.2064-2071
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    • 2012
  • 스마트 폰의 일반화로 인해 스마트폰 게임이 많이 출시되고 있지만, 주로 터치 기능을 이용하여 화면 상의 상호작용을 통한 게임이 주류를 이루고 있다. 한편 기존의 가속도센서, 방향센서 외에 자이로센서 등 단말기의 위치와 동작을 인식하는 기능은 나날이 발전하고 있다. 따라서 사용자의 동작을 단말을 통해 인식하여 사용자 단말을 게임도구로 사용하는 게임의 개발이 기술적으로 가능해지고 있으나, 아직 구체화된 사례는 발견되지 않고 있다. 본 논문에서는 단말기의 동작 인식과 단말기간 상호 통신을 결합한 새로운 형태의 게임의 기본 틀과 알고리즘을 제시하고, 그 구현 내용과 결과를 제시한다.

아스코르빈산과 티올류 및 유기산이 폴리페놀 화효소 활성에 미치는 영향 (Effects of Ascorbic Acid, Thiols and Organic Acid on Polyphenol Oxidase Activity)

  • 김안근;김유경
    • 약학회지
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    • 제45권4호
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    • pp.387-396
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    • 2001
  • The effects of ascorbic acid, thiols such as cysteine, n-acetyl-ι-cyteine, glutathione, thiourea, 2-mercaptoethanol and dithiotreithol and organic acids such as magic acid, citric acid, glycolic acid, taurine and kojic acid on polyphenol oxidate (PPO) activity were studied in order to establish if it reacts with oxidized product and/or directly inhibits the enzyme. To investigate the mechanism, the quantification of t-butylcatechol and 4-methylcatechol (phenolic compounds) as substates, their oxidized product and sulphydryl colorless additional compounds were determined by high performance liquid chromatograph (HPLC) method. Chromatographic results indicate that ascorbic acid, organic acids and lower level of cysteine reduced oxidized product of substrates back to their respective positions uf ο-diphenols. On the other hand, other thiols and high level of cysteine reacted with oxidative product of ο-diphenols and then produced sulphydryl colorless compounds. Cysteine apperars to have two types of mechanism of actions in the formation of oxidative products of substrates depending on its concentration; ascorbic acid-type and other thiols-types. The effect of ascorbic acid with thiols on polyphenol oxidase was determined by same method. Chromatographic results indicate that ascorbic acid was more reactive with oxidized product of substrates than thiols.

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전제 부정의 악센트 실현 양상 -일반 부정과 비교하여- (The Accentual Realization of Negation of Presupposition in English -In Comparison with General Negation-)

  • 전지현;박순복;김기호
    • 음성과학
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    • 제8권4호
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    • pp.259-273
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    • 2001
  • This study investigates the accentual realization of negation denying the presupposition of a previous utterance compared with that of a general negation. Specifically we study what types and positions of accent are realized in the speech of Korean speakers using English as a second language as well as English native speakers. Gussenhoven (1983) and Bolinger (1985, 1986) suggested that when presupposition of previous utterances is denied through negation, focal accent is assigned to empty (functional) words, rather than negative morphemes. The results of this study, however, show that negation sentences denying presupposition have accents not only on empty (functional) words but also on content words. Almost every English native speaker places an H* accent on the negative morphemes themselves (not, no, nothing, etc.) in general negation, as well as on the other lexical items-verbs and prepositions in our data-in negations denying presuppositions. On the other hand, Korean speakers hardly distinguish between the two kinds of negation sentences, unlike native speakers through accentual differences. Rather, they give accent an every content word, including the negative morphemes in both general negations and negations denying presuppositions. Therefore, the results of this study do not absolutely support the previous studies on the denial of presupposition.

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New 7-Hydroxycoumarin-Based Fluorescent Chemosensors for Zn(II) and Cd(II)

  • Swamy, K.M.K.;Kim, Min-Jung;Jeon, Hye-Ryeong;Jung, Ji-Young;Yoon, Ju-Young
    • Bulletin of the Korean Chemical Society
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    • 제31권12호
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    • pp.3611-3616
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    • 2010
  • Five new 4- or 8-substituted-7-hydroxycoumarin derivatives (1-5) were synthesized as fluorescent sensors for metal ions. Fluorescent changes and selectivity for metal ions were compared based on the introduction of different ligands and/or testing with different substitution positions of 7-hydroxycoumarin in aqueous solution. Especially, probes 2, 3 and 5 displayed large fluorescence enhancements with $Zn^{2+}$ and $Cd^{2+}$. Probes 2 and 3 showed moderate selectivity for $Zn^{2+}$ over $Cd^{2+}$. On the other hand, probe 4 showed large fluorescence quenching effects upon the addition of $Ag^+$ and $Hg^{2+}$.

세 갈대 개체군의 절단 부위별 삽목 생장 특성 (Growth Characteristics of Cutting Culms Sectioned at Different Positions from Three Reed Populations)

  • 홍문기;김재근
    • 한국환경복원기술학회지
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    • 제15권1호
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    • pp.53-62
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    • 2012
  • Culm cutting is very effective and convenient method for asexual propagation and even much less destructive than the other ways such as excavation of rhizomes. Despite that culm cutting is such a useful method, only few investigations for raising its efficiency have been carried out. We tried to examine the effect of different geographical populations and cutting sections on the shoot emergence, biomass production and its allocation in terms of cutting efficiency. Culms were sampled from three environmentally distinct wetlands : riparian marsh, salt marsh and montane fen and then they were cut separately into four sections from the bottom to the top part. Both factors of different population and section affected the shoot emergence together. Middle parts on the culm always showed more shoot emergence irrespective of different population. On the other hand, first section from salt marsh and fourth section from the montane fen did not exhibit any shoot emergence. Significant difference in increase of shoot emergence between different sections during investigation period was confirmed only from salt marsh population. Not only different population but also appropriate cutting section should be considered together for better efficiency in cutting of reed culms.

장미 공장생산시스템 적용을 위한 Single-node 삽목묘의 잠재생장 (Estimating Potential Growth of Single-node Cuttings for Applying Single-stemmed Rose to Factory System)

  • Kim, Wan-Soon;Lee, Yong-Beom;Nam, Yoon-Il;Kim, Hyung-Jun
    • 한국생물환경조절학회:학술대회논문집
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    • 한국생물환경조절학회 2001년도 봄 학술발표논문집
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    • pp.79-80
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    • 2001
  • This study was conducted to estimate rooting and shooting in single-node cuttings (SNC) of roses 'Rote Rose' and 'Teresa' to several conditions: growth stage, node position, and leaf area of cutting, so that single-stemmed roses (SSR) could be used in rose factory system. There was no effects of growth stage of flowering shoots far cutting on the rooting and shooting of SNC in both of the two cultivars. However, the node position and leaf area of cuttings significantly affected the rooting and shooting of SNC: the speed was accelerated with larger leaf area and upper node cuttings, but the rate showed little difference as above 95%. Based on above results, rooting and shooting in SNC was forced by leaf area mainly, followed by node positions. On the other hand, flowering rate of shoots from SNC was improved mainly with larger leaf area in cuttings. Shoots of 45cm-longer, qualified for rose factory system, increased with lower node and larger leaf area significantly. Therefore, it could be said that the potential growth of shoots from SNC would be influenced mainly by leaf area, followed by node position on cutting.

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방사선치료에 있어서 Multileaf Collimator의 원리와 그 응용 (Principles and Applications in Multileaf Collimator for Radiation Therapy)

  • 정갑수
    • 대한방사선기술학회지:방사선기술과학
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    • 제21권1호
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    • pp.24-28
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    • 1998
  • A conventional treatment machine shapes x-ray fields by a set of dense metal collimators(jaws) built into the machine. These collimators are positioned by the therapist using hand controls in the treatment room, and usually remain stationary during treatment. The collimator jaws of treatment machines produce rectangular beams. Conventional beam shaping is accomplished through the use of a combination of these collimator jaws and secondary custom beam blocks attached to the accelerator beyond the collimator Jaws. The jaw positions for a particular field can be retrieved from a computer. One application of this increased capability is replacement of beam blocks for field-shaping with the MLC. There are three basic applications of the MLC. The first application is to replace conventional blocking. A second function of the MLC is related to conformal therapy, adjusting the field shape to match the beam's eye view projection of a planning target volume during treatment. The third application is the use of the MLC to achieve beam intensity modulation. The aim of this paper is to provide basic principle and to state fundamental concepts needed to implement the use of a multileaf collimator in the conventional clinical setting. The use of MLC field shaping is likely to save time and to incur a lower operating cost when compared to the use of beam blocks.

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