• 제목/요약/키워드: plumes

검색결과 128건 처리시간 0.025초

SIMP: SLICKS AS INDICATORS FOR MARINE PROCESSES

  • Mitnik, Leonid M.;Gade, Martin;Ermakov, Stanislav A.;Lavrova, Olga Yu.;Silva, Jose B.C. da;Woolf, David K.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.950-953
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    • 2006
  • SIMP is an international project funded by INTAS aimed at improving the information content, which can be inferred from multi-sensor satellite imagery of marine coastal areas. Scientific teams from Germany, UK, Portugal, and Russia focus on the development of novel tools for marine remote sensing of the coastal zone. In particular, the project teams' benefit from the fact that surface films may enhance the signatures of hydrodynamic processes such as plumes, internal waves, eddies, etc., on microwave, optical, and infrared imagery. The project's objectives are to develop a robust methodology for identifying slick-related phenomena/processes through their surface signatures and thereby, to improve the discrimination capabilities between slicks and other oceanic and atmospheric phenomena by taking into account information gained from satellite imagery quasi-simultaneously recorded at microwave, visible and IR wavelengths. The results of the two project years are summarized. Examples are given for the project’s web presentation, laboratory and field experiments, and of the analyses of various satellite data.

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Improvement of Corona Temperature and Velocity Determination Method Using a Coronagraph Filter System

  • Cho, Kyuhyoun;Chae, Jongchul;Lim, Eun-Kyung
    • 천문학회보
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    • 제42권2호
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    • pp.85.3-86
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    • 2017
  • We have developed a methodology to determine the coronal electron temperature and solar wind speed using a four filter coronagraph system. The method developed so far have been applied to total eclipse observation and have yielded plausible results. The current methodology starts from the assumption that 1) coronal free electrons are isothermal and 2) coronal free electrons have spherically symmetric distrubution. However, the actual solar corona differs significantly from the two assumptions above. The coronal electron density is not spherically symmetric due to streamers, plumes, and coronal loops, and the electron temperature is also expected to increase rapidly with distance from the sun. We will discuss how to determine the temperature and wind speed of the corona in the case of corona with thermal structures and non-spherical symmetric electron density.

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미사일 동체에서 발생하는 Plume 간섭 효과와 제어 (Plume Interference Effect on a Missile Body and Its Control)

  • 임채민;;김희동
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1730-1735
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    • 2003
  • The plume-induced shock wave is a complex phenomenon, consisting of plume-induced boundary layer separation, separated shear layer, multiple shock waves, and their interactions. The knowledge base of plume interference effect on powered missiles and flight vehicles is not yet adequate to get an overall insight of the flow physics. Computational studies are performed to better understand the flow physics of the plume-induced shock and separation particularly at high plume to exit pressure ratio. Test model configurations are a simplified missile model and two rounded and porous afterbodies to simulate moderately and highly underexpanded exhaust plumes at the transonic/supersonic speeds. The result shows that the rounded afterbody and porous wall attached at the missile base can alleviate the plume-induced shock wave phenomenon, and improve the control of the missile body.

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분무패턴 분석을 이용한 가솔린 직접 분사식 인젝터의 개별 분무플럼 분무각 측정 방법에 대한 연구 (A Study on the Measurement of Individual Spray Cone Angle from Gasoline Direct Injection Injector using Spray Pattern Analysis)

  • 박정현;조한빈;박수한
    • 한국분무공학회지
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    • 제25권2호
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    • pp.51-59
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    • 2020
  • The purpose of this study is to propose and compare methods for measuring individual spray cone angles using spray cross-section images. In direct injection gasoline engines, it was believed that the distribution of air-fuel mixture in the combustion chamber directly affected combustion performance and emission formation. However, since gasoline direct injection (GDI) injectors have a small injection angle, interference between individual spray plumes occurs. Therefore, GDI injectors have only measured the spray angle of the entire spray. To overcome these limitations, three methods of indirectly measuring the spray cone angles of individual spray plume were presented and compared by forming sheet beams using Nd:YAG laser and acquiring spray cross-section images. Each method currently has advantages and disadvantages, and research to apply the method suitable for various GDI injectors needs to be continued.

Modeling of SO$_2$ Emissions from Yatagan Power Plant

  • Im, Ulas;Yenigun, Orhan
    • 한국환경과학회:학술대회논문집
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    • 한국환경과학회 2003년도 International Symposium on Clean Environment
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    • pp.69-72
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    • 2003
  • The meteorological model, CALMET, and its plume dispersion model, CALPUFF, were used in order to simulate the dispersion of $SO_2$ emitted from Yatagan Power Plant and its effect on Yatagan district in the episodic event on December 2 and 3, 2000. It is found that south westerly and light winds and the nighttime surface inversion layers lead to accumulation of pollutants over Yatagan district. The results are compared with the measurements done by Local Environmental Authorities of Mu la. The simulation results indicate that the maximum ground level concentrations were found northeast from the source, which agrees with experimental measurement. On the other hand, the magnitude of results obtained with the model shows some differences compared with experimental measurements.

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몽골인의 남자 관모에 관한 연구 - "집사(集史)"를 중심으로 - (A Study on the Mongolian Male Headgear - focused on Jip-Sah -)

  • 김미자
    • 대한가정학회지
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    • 제44권1호
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    • pp.151-157
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    • 2006
  • Ten types of male headgear-Kwonwoonkwan, crown-like headgear, hats with a square flap, hats with feathers, crowns with plumes, Ballip, hats with flat crowns, Somo, turban, and fur hats-were described in Jip-Sah, which was published in the 14th century. Mongolian people used summer headgear, winter hats, and crown ornaments, which had been used until the Ch'ing dynasty of China. From the late 12th century to 1304, the headgear styles remained the same, suggesting that the Mongolian people kept their tradition. Kwonwoonkwan, crown-like headgear, and Somo, presented in Jip-Sah, were also described in U. Yadamsuren's album, a pictorial depiction of the 20th century Mongolian headgear.

Field Applicability of Design Methodologies for Groundwater Quality Monitoring Network

  • Lee, Sang-Il
    • Korean Journal of Hydrosciences
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    • 제10권
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    • pp.47-58
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    • 1999
  • Protection of groundwater resources from contamination has been of increasing concern throughout the past decades. In practice, however, groundwater monitoring is performed based on the experience and intuition of experts or on the convenience. In dealing with groundwater contamination, we need to know what contaminants have the potential to threat the water quality and the distribution and concentration of the plumes. Monitoring of the subsurface environment through remote geophysical techniques or direct sampling from wells can provide such information. Once known, the plume can be properly menaged. Evaluation of existing methodologies for groundwater monitoring network design revealed that one should select an appropriate design method based on the purpose of the network and the avaliability of field information. Integer programming approach, one of the general purpose network design tools, and a cost-to-go function evaluation approach for special purpose network design were tested for field applicability. For the same contaminated aquifer, two approaches resulted in different well locations. The amount of information, however, was about the same.

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APPLICABILITY OF MODELS FOR BOSTON OUTFALL PLUMES

  • Chung, Yong-tai;Kim, Gyoung-Wan
    • Water Engineering Research
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    • 제1권4호
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    • pp.309-320
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    • 2000
  • In this study, laboratory study of the behavior of wastewater discharged from the Boston ocean outfall was compared with the predictions of mathematical models. The dta sets cover broad ranges of discharge conditions and oceanic conditions, and are associated with a typical type of outfall discharges with multiport diffusers. The laboratory data sets were obtained in density stratified towing tanks. These data sets were used to evaluate four commonly used models: UM, UDKHDEN, RSB and CORMI$\times$2 for minimum dilution, the height to the top of the wastefield, and wastefield thickness. For minimum diluation and height to the top of the wastefield, UM and RSB predictions agree well with laboratory data. UDKHDEN overestimated the minimum dilution and height to the top of the wastefield while CORMI$\times$2 underestimated these values. All of the model predictions for the wastefield thickness were widely scattered. about the measured values. The hydraulic model study reproduced the major features observed in the laboratory. It also afforded considerable insight into the mechanics of mixing of multiport risers which could not have been obtained either from the laboratory test or the mathematical models.

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측벽효과를 고려한 개구부 분출화염 거동 연구 (Study on the Ejected Plume from Opening Regarding Side-wall Effect in Fire)

  • 정재군;신이철
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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    • pp.219-220
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    • 2016
  • The behavior of fire plumes has not yet been clearly identified for cases where sidewalls are installed near an opening in an unconfined space. In this research, we aim to quantitatively identify the effects on fire spread when sidewalls are located on both sides of an opening. Specifically, we focus on the effects on the fire plume of the relation between the location of sidewalls and the opening, and carry out a scale-model experiment to devise a flame height model and to evaluate the temperature distribution along the central axis of the flame.

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멸종, 범람 현무암과 지구자기장 (Extinction, Flood Basalts, and Geomagnetic Field)

  • 유용재
    • 한국지구물리탐사학회:학술대회논문집
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    • 한국지구물리탐사학회 2008년도 공동학술대회
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    • pp.33-36
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    • 2008
  • 대량 멸종과 범람 현무암 분출은 동일 시기에 관찰된다. 지구자기장의 역전이 결여된 Superchorn은 현생대에 3회 존재한다 (118-83 Ma의 CNS, 310-260 Ma의 KLRS, 490-460 Ma의 MLRS). 이들 각각의 Superchron이 끝나는 시점을 기준으로 2천 만년 이내에 대규모 범람 현무암의 분출이 관측된다. 대형 맨틀 Plume의 상승이 현무암 분출을 야기하고, 현무암의 대량 피복이 급격한 기후 변화를 유발하여, 궁극적으로는 생태계의 파괴로 이어진다.

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