• 제목/요약/키워드: scale formation

검색결과 1,224건 처리시간 0.038초

국지지역 도로 기반 시설에서 안전운전을 위한 경보 정보 설계 (Amber Information Design to Keep Safety-Driving Under Road Structure at Local-Scale Geographic)

  • 박종찬;홍규장
    • 전기학회논문지P
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    • 제58권1호
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    • pp.48-55
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    • 2009
  • In order to keep safe driving conditions under road networks, there are several formations such as road structure, road surface condition, traffic occupancy and supplement of an accurate information of traffic status ahead To support safe-driving on each road formation, each formation is supplied with various information to help the driver. However, in some cases like rapid status change at local-scale geography, traffic information systems often displays insufficient information because of the lack of information correlation. In order to accurately aware the driver, all road formation must be in sync. It is important to supply accurate information to the driver because this information directly impacts the drivers on the road. This paper discusses the amber information to keep the least safety driving over road formations including tunnels and bridges. This paper also will propose the informations for safe-driving conditions, information linkage on the road and rule-base safety information, as ITS technology, being displayed for all drivers under the worst weather conditions.

A New Species of Leptostrobus from the Upper Triassic Amisan Formation of the Nampo Group in Korea

  • Kim, Jong-Heon;Kim, Hee-Soo;Lee, Bong-Jae;Kim, Jung-Min;Lee, Hee-Kwon
    • 한국지구과학회지
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    • 제23권1호
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    • pp.30-37
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    • 2002
  • Leptostrobus myeongamensis sp. nov. is newly described from the well-preserved but broken material occurring in the Upper Triassic Amisan Formation of the Nampo Group in Korea. This species is characterized by its lateral appendages of cone axis, each consisting of a rounded capsule and small scale leaf, and by its cone base covered with small scale leaves, the same size as in cone axis. This species is the first record from the Mesozoic strata in Korea.

Cosmological Information from the Small-scale Redshift Space Distortions

  • Tonegawa, Motonari;Park, Changbom;Zheng, Yi;Kim, Juhan;Park, Hyunbae;Hong, Sungwook
    • 천문학회보
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    • 제44권2호
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    • pp.52.3-52.3
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    • 2019
  • We present our first attempt at understanding the dual impact of the large-scale density and velocity environment on the formation of very first astrophysical objects in the Universe. Following the recently developed quasi-linear perturbation theory on this effect, we introduce the publicly available initial condition generator of ours, BCCOMICS (Baryon Cold dark matter COsMological Inital Condition generator for Small scales), which provides so far the most self-consistent treatment of this physics beyond the usual linear perturbation theory. From a suite of uniform-grid simulations of N-body+hydro+BCCOMICS, we find that the formation of first astrophysical objects is strongly affected by both the density and velocity environment. Overdensity and streming-velocity (of baryon against cold dark matter) are found to give positive and negative impact on the formation of astrophysical objects, which we quantify in terms of various physical variables.

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Formation CubeSat Constellation, SNIPE mission

  • Lee, Jaejin
    • 천문학회보
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    • 제46권1호
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    • pp.58.4-59
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    • 2021
  • This presentation introduces Korea's SNIPE (Small scale magNespheric and Ionospheric Plasma Experiment) mission, formation flying CubeSat constellation. Observing particles and waves on a single satellite suffers from inherent space-time ambiguity. To observe spatial and temporal variations of the micro-scale plasma structures on the topside ionosphere, four 6U CubeSats (~ 10 kg) will be launched into a polar orbit of the altitude of ~500 km in 2021. The distances of each satellite will be controlled from 10 km to more than 100 km by formation flying algorithm. The SNIPE mission is equipped with identical scientific instruments, solid-state telescope, magnetometer, and Langmuir probe. All the payloads have a high temporal resolution (sampling rates of about 10 Hz). Iridium modules provide an opportunity to upload changes in operational modes when geomagnetic storms occur. SNIPE's observations of the dimensions, occurrence rates, amplitudes, and spatiotemporal evolution of polar cap patches, field-aligned currents (FAC), radiation belt microbursts, and equatorial and mid-latitude plasma blobs and bubbles will determine their significance to the solar wind-magnetosphere-ionosphere interaction and quantify their impact on space weather.

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스케일 층의 생성 및 성장을 고려한 가열로 내 슬랩의 승온 특성 해석에 관한 연구 (A Numerical Study on the Slab Heating Characteristics in a Reheating Furnace with the Formation and Growth of Scale on the Slab Surface)

  • 이동은;장정현;김종민;홍동진;박해두;박윤범;김만영
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 춘계학술대회논문집
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    • pp.109-112
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    • 2008
  • In this work, a mathematical heat transfer model of a walking-beam type reheating furnace that can predict the formation and growth of the scale layer, which is produced due to oxidative reaction between the furnace oxidizing atmosphere and the steel surface in the reheating furnace, has been developed. The model can also predict the heat flux distribution within the furnace and the temperature distribution in the slab and scale throughout the reheating furnace process by considering the heat exchange between the slab and its surroundings in the furnace, including radiant heat transfer among the slabs, the skids, the hot gases and the furnace wall as well as the gas convection heat transfer in the furnace. Using the model developed in this work, the effects of the scale layer on the heat transfer characteristics and temperature behavior of the slab is investigated. A comparison is also made between the predictions of the present model and the data from an in situ measurement in the furnace, and a reasonable agreement is founded.

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패모의 초기배양과 모구의 저온처리가 자구형성에 미치는 영향 (Establishment of in Vitro Culture and Effect of Chilling Treatment of Mother Bulb On Bulblet Formation in Fritillaria thunbergii Miq.)

  • 유광진;백기엽;성낙술;최인식;조진태
    • 한국약용작물학회지
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    • 제2권3호
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    • pp.211-218
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    • 1994
  • 조직배양에 의한 패모(Fritillaria thuubergii Miq)의 대량번식 체계를 확립하기 위한 기초실험으로써 인편배양시 오염을 감소에 미치는 모구의 표면살균방법, 항생제처리 효과, 모구의 조온처리 기간이 자구형성에 미치는 영향을 구명하고자 실험한 결과는 다음과 같다. 1. 포장재배한 패모를 수확한 후 인편 배양하였을 경우 외측인편이 내측인편보다 오염율이 현저히 높아 배양재료로는 부적합하였고, 내측인편은 70% 에탄을에 30분간 침지후 $4{\sim}5%\;sodium\;hypochlorite$ 용액에 $10{\sim}15$분간 표면살균함으로써 오염율을 줄일 수 있었다. 2. 배지내 항생제, 살균제 및 $lncyte^{tm}$첨가가 세균성 오염을 줄이는 데는 효과가 있었으나 곰팡이에 의한 오염은 방지할 수 없었다. 그러나 오염정도를 지연시키는 효과는 있었다. 3. 건조 저장시에는 $10^{\circ}C$에서 $2{\sim}4$주, 습윤저장시에는 $4{\sim}6$에서 자구 형성이 양호하였으며, kinetin첨가는 대조구에 비해 자구형성수를 크게 증가시키지는 않았다. 건조저장시 4주 이후에는 구가 마르면서 고사하는 현상을 나타내어 건조 저장이 패모의 저온처리 방법으로 적당하지 못하다고 생각되었다. 한편, 습윤 저장 6주후 kinetin $3{\sim}5mg/L$첨가구에서는 배양절편체당 10개 이상의 자구가 형성되었다.

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COSMIC RAY ACCELERATION DURING LARGE SCALE STRUCTURE FORMATION

  • BLASI PASQUALE
    • 천문학회지
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    • 제37권5호
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    • pp.483-491
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    • 2004
  • Clusters of galaxies are storage rooms of cosmic rays. They confine the hadronic component of cosmic rays over cosmological time scales due to diffusion, and the electron component due to energy losses. Hadronic cosmic rays can be accelerated during the process of structure formation, because of the supersonic motion of gas in the potential wells created by dark matter. At the shock waves that result from this motion, charged particles can be energized through the first order Fermi process. After discussing the most important evidences for non-thermal phenomena in large scale structures, we describe in some detail the main issues related to the acceleration of particles at these shock waves, emphasizing the possible role of the dynamical backreaction of the accelerated particles on the plasmas involved.

Bench-scale 고압반응기 내의 미세액적분사에 따른 $SF_6$ 하이드레이트 형성 거동 연구 (Study on $SF_6$ hydrate Formation and Dissociation Behavior inside of Bench-scale High Pressure Reactor)

  • 문동현;이재정;신형준;이주동;이강우
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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    • pp.687-690
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    • 2009
  • 본 연구에서는 가스 하이드레이트 형성과정에서 발생할 수 있는 유도지체시간을 줄이고 전체 가스 저장량과 반응 속도의 향상을 위하여 이류체 분사 방식을 이용하여 물분자의 액적을 최소화하는 실험을 통하여, 미세액적 분사에 따른 하이드레이트 형성 시간을 확인하였으며, 반응기 내부의 온도 변화를 확인하여 반응기 내부의 하이드레이트 형성 거동을 확인하고 이를 통하여 상용화를 위한 반응기 설계의 기초 자료로 활용하고자 하였다.

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Simulation of the SDSS Survey Region of the Universe

  • Park, Chang-Bom;Van De Weygaert, Rien;Wojceich, Hellwing;Kim, Ju-Han
    • 천문학회보
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    • 제35권2호
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    • pp.43.2-43.2
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    • 2010
  • We reconstruct the large-scale initial density field from the distribution of galaxies observed by the Sloan Digital Sky Survey (SDSS). After adding the small-scale fluctuations to match the power spectrum to that of the standard LCDM model, we make a cosmological N-body simulation of formation of structures from the initial conditions. Properties of the objects formed in the simulation can be statistically compared with those of the observed SDSS galaxies. The simulation makes it possible to know the past history of evolution of objects located in different environments, and also gives us information on the environmental parameters that cannot be directly obtained observationally. It is hoped that this comparative study leads us to better understanding of formation and evolution of galaxies in conjunction with large-scale structures in the universe.

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TiAlCrSiN 박막의 고온 산화 부식 (High-temperature Oxidation of the TiAlCrSiN Film)

  • 이동복;김민정
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2016년도 추계학술대회 논문집
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    • pp.107-107
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    • 2016
  • TiCrAlSiN films were developed in order to improve the high-temperature oxidation resistance, corrosion resistance, and mechanical properties of conventional TiN films that are widely used as hard films to protect and increase the lifetime and performance of cutting tools or die molds. In this study, a nano-multilayered TiAlCrSiN film was deposited by cathodic arc plasma deposition. It displayed relatively good oxidation resistance at $700-900^{\circ}C$, owing to the formation protective oxides of $Al_2O_3$, $Cr_2O_3$, and $SiO_2$, and semiprotective $TiO_2$. At $1000^{\circ}C$, the increased temperature led to the formation of the imperfect oxide scale that consisted primarily of the outer ($TiO_2$,$Al_2O_3$)-mixed scale and inner ($TiO_2$, $Al_2O_3$, $Cr_2O_3$)-mixed scale.

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