• 제목/요약/키워드: Relativity

검색결과 289건 처리시간 0.026초

중력파 검출 - 새로운 천문학의 시대를 위하여 (Gravitational-wave detection - for the new age of astronomy)

  • 오정근
    • 천문학회보
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    • 제40권1호
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    • pp.58.1-58.1
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    • 2015
  • Gravitational-wave has been predicted by Einstein's general relativity in 1916, but its direct detection has failed to date despite of the persistent efforts in the last fifty years in the ground-based gravitational wave detectors. In the centennial year of the birth of general relativity, 'advanced LIGO', one of the most promising Earth-based gravitational wave detectors, plans to start commissioning for the successful discovery of gravitational waves. In addition, a pathfinder satellite of eLISA project, a space-based GW antenna by European Space Agency (ESA), will be launched in the mid of this year. In this talk, we review the current status of gravitational waves detection experiments and discuss its scientific impacts and the possibility of opening the new age of astronomy.

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일반상대성이론과 현대우주론 (General Relativity and Modern Cosmology)

  • 황재찬
    • 천문학회보
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    • 제40권1호
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    • pp.57.5-58
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    • 2015
  • We describe relations between modern cosmology and general relativity in the historical context. We reveal some ironies imbedded in Einstein's final correction of his gravitational field equation in the context of cosmology in 1917 which has apparently opened a new era of modern physical cosmology. The ugly (according to Einstein) correction term was introduced only to build a static cosmology which turns out to be in flat contradiction with observation. Somehow, however, it is the correction term which has saved the modern cosmology from the genuine creativity of nature continuously revealed by astronomical observations. Whether the present precision cosmology is also a correct one is often ignored by the practitioners but still a pressing open question left for future theoretical and observational pursuits.

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On Interpretation of Hyperbolic Angle

  • Aktas, Busra;Gundogan, Halit;Durmaz, Olgun
    • Kyungpook Mathematical Journal
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    • 제60권2호
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    • pp.375-385
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    • 2020
  • Minkowski spaces have long been investigated with respect to certain properties and substructues such as hyperbolic curves, hyperbolic angles and hyperbolic arc length. In 2009, based on these properties, Chung et al. [3] defined the basic concepts of special relativity, and thus; they interpreted the geometry of the Minkowski spaces. Then, in 2017, E. Nesovic [6] showed the geometric meaning of pseudo angles by interpreting the angle among the unit timelike, spacelike and null vectors on the Minkowski plane. In this study, we show that hyperbolic angle depends on time, t. Moreover, using this fact, we investigate the angles between the unit timelike and spacelike vectors.

옥상용 합성고분자 시트를 애용한 지붕노출 시스템 적용에 관한 연구 (A Study on Application of Exposure System using Waterproofing Sheets of Synthetic Polymer for Rooftop)

  • 이상수;김수련;곽규성;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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    • pp.179-183
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    • 2005
  • In apply roof waterproof system using of synthetic high polymer sheet for rooftop measure physical performance (tension$\cdot$tearing ability, temperature relativity, heating stretch performance, junction performance, wind resistance test) by various test environment condition waterproof test of structure and performance of construction work aspect, present suitable form of construction work under these environment. Also, wish to improve durability of concrete structure as that examine in priority about adhesion method and joint junction method with waterproof out surface, and present new direction about roof system application of waterproofing method for rooftop.

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$Alq_3$의 녹색발광특성에 관한 연구 (A Study on the Green Eemission Ccharacteristics of $Alq_3$)

  • 강용철;전동규;송진원;김영근;김주승;구할본;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.957-960
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    • 2002
  • Electroluminescence(EL) from conjugated polymers has recently received great attention because polymer light-emitting diodes(LEDs) clealy have potential for applications such as large-area displays. The operation of polymer LEDs is based on double injection of electrons and holes from the elextrodes, followed by formation of excitons whose radiative decay results in light emission at wavelength characteristic to the material. In this paper, we fabricated the single layer EL device using $Alq_3$ as emitting material. According as turn on voltage could know about 5.5V in voltage-current characteristics and voltage rise, current could see that increase as non-linear. Current and ruminance can see that express similar relativity in voltage, and could know that ruminance is expressing current relativity.

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나노구조 박막의 EL 특성 (Electro-luminescence Characteristics of Nano-Structural Thin Film)

  • 최용성;조장훈;송진원;이경섭
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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    • pp.274-275
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    • 2006
  • A new thin film materials can be built up at the molecular level, and the relationship between these artificial structures and the properties of materials can be explored. In this paper, in order to confirm the application possibility to the molecular electronic device of the organic materials, we have investigated electro-luminescent (EL) characteristics of organic EL device using $Alq_3$, PBD as emitting material. Current and luminance can be seen that express a similar relativity in voltage and could know that luminance is expressing current relativity.

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남성 패션에 표현된 문화 꼴라쥬 현상 (Cultural Collage in Men's Fashion)

  • 이민선
    • 복식문화연구
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    • 제13권3호
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    • pp.469-480
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    • 2005
  • The purpose of this study is to analyze the meaning and the value of the cultural collage expressed in men's fashion. As for the research methodology, literary research was under taken to study psychoanalytical and socioeconomic contexts in which cultural collage has been formed. In addition, demonstrative studies in men's fashion were undertaken through the analysis of pictures. The cultural collage is defined as a phenomena of making creativity by combining cultures which have no relevance. In psychological and sociological aspects, the rise of the cultural collage is caused by multinational corporation, pluralization of identity, information society, consumer oriented production, consumer society and inundation of kitsch. On the basis of the characteristics and social backgrounds of cultural collage, the aesthetic values of men's fashion can be explained by pluralism de-generalization and relativity.

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다층구조 OLED소자의 발광특성 (Emission Characteristics of Multilayer Structure OLED)

  • 최영일;조수영
    • 전자공학회논문지 IE
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    • 제48권4호
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    • pp.25-29
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    • 2011
  • 유기 EL소자는 제작이 쉽고 휘도가 높아 CRT와 LED 대신 평판 디스플레이 패널의 광원으로써 많이 연구되어 지고 있으며, OLED 소자중 청색 OLED는 풀컬러 적용 어플리케이션에 적용할 수 있기 때문에 이에 대한 연구가 이루어 지고 있다. 본 연구에서는, 발광 소재로 PBD, Alq3를 사용하여 유기 EL 디바이스의 전기 발광 특성을 측정하였으며, 전류와 휘도는 전압과의 관계에서 알 수 있었고 휘도와 전류의 관계를 제시하였다.

기준계와 운동의 상대성에 대한 중학교 1학년의 개념 (Preconceptions on the Reference Frame and Relativity of Motion of Grade 7 Pupils)

  • 오원근;김재우
    • 한국과학교육학회지
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    • 제17권4호
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    • pp.373-381
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    • 1997
  • To investigate the preconceptions on the reference frame and relativity of motion, 251 of grade 7 pupils were selected. The questionnaire has 15 questions consisted of four test domains made by the researchers: object looks rest or moving in the rest frame, object looks rest or moving in the moving frame. The result shows that pupils took the observations in the moving frame for those in the rest frame, or vice versa. In addition, their answers varied according as the context of the observation differed.

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