• 제목/요약/키워드: local circulation

검색결과 311건 처리시간 0.026초

Impact of Wind Profiler Data Assimilation on Wind Field Assessment over Coastal Areas

  • Park, Soon-Young;Lee, Hwa-Woon;Lee, Soon-Hwan;Kim, Dong-Hyeok
    • Asian Journal of Atmospheric Environment
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    • 제4권3호
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    • pp.198-210
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    • 2010
  • Precise analysis of local winds for the prediction of atmospheric phenomena in the planetary boundary layer is extremely important. In this study, wind profiler data with fine time resolution and density in the lower troposphere were used to improve the performance of a numerical atmospheric model of a complex coastal area. Three-dimensional variational data assimilation (3DVAR) was used to assimilate profiler data. Two experiments were conducted to determine the effects of the profiler data on model results. First, we performed an observing system experiment. Second, we implemented a sensitivity test of data assimilation intervals to extend the advantages of the profiler to data assimilation. The lowest errors were observed when using both radio sonde and profiler data to interpret vertical and surface observation data. The sensitivity to the assimilation interval differed according to the synoptic conditions when the focus was on the surface results. The sensitivity to the weak synoptic effect was much larger than to the strong synoptic effect. The hourly-assimilated case showed the lowest root mean square error (RMSE, 1.62 m/s) and highest index of agreement (IOA, 0.82) under weak synoptic conditions, whereas the statistics in the 1, 3, and 6 hourly-assimilated cases were similar under strong synoptic conditions. This indicates that the profiler data better represent complex local circulation in the model with high time and vertical resolution, particularly when the synoptic effect is weak.

레이더 자료동화에 따른 기상장모의 민감도에 관한 수치연구 (Numerical Study on the Sensitivity of Meteorological Field Variation due to Radar Data Assimilation)

  • 이순환;박근영;류찬수
    • 한국환경과학회지
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    • 제15권1호
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    • pp.9-19
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    • 2006
  • The purpose of this research is development of radar data assimilation observed at Jindo S-band radar The accurate observational data assimilation system is one of the important factors to meteorological numerical prediction of the region scale. Diagnostic analysis system LAPS(Local Analysis and Prediction System) developed by US FSL(Forecast Systems Laboratory) is adopted assimilation system of the Honam district forecasting system. The LAPS system was adjusted in calculation environment in the Honam district. And the improvement in the predictability by the application of the LAPS system was confirmed by the experiment applied to Honam district local severe rain case of generating 22 July 2003. The results are as follows: 1) Precipitation amounts of Gwangju is strong associated with the strong in lower level from analysis of aerological data. This indicated the circulation field especially, 850hPa layer, acts important role to precipitation in Homan area. 2) Wind in coastal area tends to be stronger than inland area and radar data show the strong wind in conversions zone around front. 3) Radar data assimilation make the precipitation area be extended and maximum amount of precipitation be smaller. 4) In respect to contribution rate of different height wind field on precipitation variation, radar data assimilation of upper level is smaller than that of lower level.

용평 알파인 경기장에서 겨울철 바람의 일변화 및 난류 특성분석 (An Analysis of the Wintertime Diurnal Wind Variation and Turbulent Characteristics over Yongpyong Alpine Slope)

  • 전혜림;김병곤;은승희;이영희;최병철
    • 대기
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    • 제26권3호
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    • pp.401-412
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    • 2016
  • A 3D sonic anemometer has been installed at Yongpyong alpine slope since Oct. 23th 2014 to observe the slope winds and to analyze turbulent characteristics with the change in surface cover (grass and snow) and the synoptic wind strength. Eddy covariance method has been applied to calculate the turbulent quantity after coordinate transformation of a planar-fit rotation. We have carefully selected 3 good episodes in the winter season (23 October 2014 to 28 February 2015) for each category (9 days in total), such as grass and snow covers in case of weak synoptic wind condition, and grass cover of strong synoptic wind. The diurnal variations of the slope winds were well developed like the upslope wind in the daytime and downslope wind in the nighttime for both surface covers (grass and snow) in the weak synoptic forcing, when accordingly both heat and momentum fluxes significantly increased in the daytime and decreased in the nighttime. Meanwhile, diurnal variation of heat flux was not present on the snow cover probably in associated with significant fraction of sunlight reflection due to high albedo especially during the daytime in comparison to those on the grass cover. In the strong synoptic regime, the most dominant feature at Yongpyong, only the southeasterly downslope winds were steadily generated irrespective of day and night with significant increases in momentum flux and turbulent kinetic energy as well, which could suggest that local circulations are suppressed by the synoptic scale forcing. In spite of only one season analysis applied to the limited domain, this kind of an observation-based study will provide the basis for understanding of the local wind circulation in the complex mountain domain such as Gangwon in Korea.

광고산업의 집적 특성과 광고제작의 공간적 네트워크 (Agglomeration Patterns of Advertising Industries and Spatial Networks of Advertisement Production)

  • 구양미
    • 대한지리학회지
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    • 제45권2호
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    • pp.256-274
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    • 2010
  • 본 연구의 목적은 국내 광고산업의 집적 특성과 광고제작의 공간적 네트워크를 고찰하는 것이다. 광고산업은 다른 비즈니스 서비스와 마찬가지로 서울의 집중도가 높기 때문에 서울 내에서의 집적 특성을 중점적으로 분석하였다. 업종별 종사자수의 지역별 비중과 더불어 로컬 모란 I와 입지계수 방법이 분석에 이용되었다. 광고산업의 강남지역 집중이 두드러지게 나타나는데, 이것은 신생 기업들의 강남지역 지향 입지와 국내 진입 외국계 광고대행사의 강남지역 선호와 관련이 있다. 또한 네트워크 분석 방법을 이용해 TV광고 제작의 공간적 네트워크를 분석했다. 광고대행사-광고제작사 네트워크 매트릭스를 구축하고, 이를 지역 매트릭스로 변환한 후, 중심성 분석과 중개 분석을 통해 광고제작의 공간적 네트워크를 고찰하였다. 이를 통해 강남 세부지역의 상이한 역할과 지위를 알 수 있는데, 강남지역 내부와 외부의 광고대행사들이 강남지역에 있는 광고제작사에 대부분의 광고제작을 아웃소싱하고 있다. 이러한 분석을 통해 광고산업이 강남지역이 광고제작의 목적지로서 뿐 아니라 강남지역에서 광고제작 네트워크가 순환되고 있음을 알 수 있다.

Dynamic Susceptibility Contrast Magnetic Resonance Images를 이용한 뇌혈류량 지도 구성 (Cerebral Blood Volume Mapping from Dynamic Susceptibility Contrast Magnetic Resonance Images)

  • 김수정;이선규;김광기;김종효;민병구
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1998년도 추계학술대회
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    • pp.281-282
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    • 1998
  • Recently, there has been growing interest in the assessment of physiological parameters on brain perfusion that provide more information than pure morphologic diagnosis. Quantification of parameters that characterize cerebral micro-circulation with magnetic resonance imaging is of great relevance for clinical application. We determine the local tissue concentration by exponential relationship between the relative signal reduction S(t)/$S_0$ and local tissue concentration of contrast material $C_m(t)$ in dynamic susceptibility contrast enhanced MR imaging. And then we made relative regional blood volume map by calculating the area under the measured concentration-time curves $C_m(t)$ during first pass of paramagnetic contrast material as a preliminary step for perfusion map. These images make it possible to compare the rCBV in different brain regions in one individual at a time. We have it in contemplation to obtain arterial and brain signal time curves simultaneously to make absolute rCBV and perfusion (rCBF) map. These maps may provide the method of comparative investigations of different patients having strong variation in AIF.

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전흉부 재건을 위한 국소 피판술의 선택 (Local Flap Algorithm for the Reconstruction of Anterior Chest Wall Defects)

  • 김지훈;김의식;황재하;김광석;이삼용
    • Archives of Plastic Surgery
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    • 제36권4호
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    • pp.397-405
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    • 2009
  • Purpose: Soft tissue defect of anterior chest wall is caused by trauma, infection, tumors and irradiation. To reconstruct damaged anterior chest wall does require to consider the patient's body condition, the cause, the location, the depth and the size of deletion, the circulation of surrounding tissue and minimization of functional and cosmetic disability. In this report, we suggest the algorithm of configuration for reconstruction methods. Methods: A retrospective study of 20 patients who underwent anterior chest wall reconstruction with pedicled musculocutaneous flap and fasciocutaneous flap was conducted. We collected the information of the patient's body condition, the cause, the size, the depth and the location of deletion, implemented flap and complication. We observed and evaluated flap compatibility, functional and cosmetic results. Patients completed survey about the extent to their satisfaction. Result: Follow up period after surgery was from 6 to 26 months, survival of flap were confirmed in all of patients' case. Two cases of local necrosis, one case of wound disruption were reported, but all these were cured by the debridement and primary closure. One hematoma and one seroma formation were observed in donor site. Longer surgery time, more bleeding amount and more transfusion volume were reported in the group of musculocutenous flap. Conclusion: Long term follow up result showed the successful reconstruction in all patients without recurrence and with minimal donor site morbidity. In addition, the patients' satisfaction for cosmetic and functional results were scaled relatively higher. This confirmed the importance of reconstruction algorithm for the chest wall reconstruction.

전시 국민생활안정 유지방안 (Policy Plans for the Maintenance of Public Security of Living During the War)

  • 길병옥
    • 안보군사학연구
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    • 통권5호
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    • pp.131-172
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    • 2007
  • Government duties in the cases of crisis are aimed at supporting efficient military operations in the fields of non-military affairs and resource mobilization, maintenance of government functions, and search for the public security of living during the war. In crisis, the government must change its functions into the total-war system with all resources available for the efficient performance of military operations, war economy, public safety and security as well as government continuance. The main contents of "Chung-Mu Plan" include the alternative measures to control the circulation of life necessities, emergency electricity, water and gas; recover public facilities from the disaster; and accommodate the wounded and refugees. Governments have practiced Ul-chi and ChungMoo exercises to improve government's management capabilities and master standard operating procedures including systematic distribution plans in the national and local level. However, such plans have not yet sufficient enough for the maintenance of public security of living. In addition to the conceptual ambiguity, major problems are the inappropriate system of the war economy, legal institutions, and administrative SOPs for the efficient maintenance of it. Thus, for the betterment of national crisis management system, the government should have the manual stated from every step and level dealing with crisis to the legal institutions. It is important to empower the National Emergency Planning Commission for the policy consistency and efficient/effective implementation. The comprehensive plans must have an integrated cooperative system of the central/local governments, military and civil society with actual practices and exercises for the maintenance of the public security of living.

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황해동측 연안성의 조류 및 풍성류 모형 (Modeling of Tidal and Wind-Driven Currents in Eastern Coastal Waters of the Yellow Sea)

  • Ro, Young-Jae;You, Ik-Hwan
    • 한국해안해양공학회지
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    • 제4권4호
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    • pp.231-242
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    • 1992
  • 분 연구에서는 수치모형을 이용하여 조류 및 취송류의 순환형태를 고찰하였다. 사용된 모형은 유체의 운동 및 연속방정식에 기초한 연직평균 2차편 모형으로서 양해법을 사용하며, 개방경계에서의 해수면 변화와 바람의 전단력에 의한 forcing을 포함한다. 모형의 영역은 북위 35$^{\circ}$~36$^{\circ}$40', 동경 125$^{\circ}$~126$^{\circ}$40'이며 경사간격은 x, y 방향 공히 5km이다. 피해측에서 22일간 관측된 조석(2개 지점) 및 조류(1개 지점) 자료와 비교한 결과 본 모형은 4개 주요 분조에 의한 조석 및 조류를 정확도 90% 이내로 재현하였다. 여섯 가지 경우의 가상적인 바람에 대한 해석을 통하여 흐름의 분포양상과 지역적인 특성을 고찰하였다. 그 결과, 풍향에 관계 없이 강한 연안류가 발생하며, 또한 해저지형의 영향으로 부안 외해측에 주반경 40km의 지역적인 과류가 발생함을 확인하였다.

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하계 인공용승구조물 주변해역의 물리환경변화 (Variation of Physical Environment near the Artificial Upwelling Structure during the Summer)

  • 서호산;김동선
    • 해양환경안전학회지
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    • 제21권4호
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    • pp.372-380
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    • 2015
  • 인공용승구조물 설치 전 후 주변해역의 하계 물리환경특성을 조사하였다. 구조물 설치 전(2002년)의 수온구조는 수심 30m에 강한 성층이 형성되었다. 한편 구조물 설치 3~4년 후(2012, 2013년)의 수온구조는 조류방향에 따라 구조물에 의한 성층의 형성수심 및 세기가 변화하였다. 이와 같은 현상은 구조물에 의한 연직류의 효과로 하계 강한 성층에 의해 저층에 분포하는 저수온수가 상승류에 의해 부상하여 성층분포에 영향을 미친 것으로 판단한다. 또한 구조물 설치 이후 연직류의 분포를 보면, 구조물 중심으로 국지적인 상승류 및 하강류가 혼재하여 나타났다. 즉 연직류는 조류방향에 따라 시 공간적인 변화를 보이면서 흐름이 진행하는 방향의 구조물 후면부에서 형성하는 상승류에 의해 성층이 약화되는 현상을 볼 수 있다. 또한 구조물에 의해 발생하는 연직류는 보다 넓은 해역으로 확장하여 발생한다. 본 연구해역에 설치한 인공용승구조물에 의해 발생하는 국지적인 용승은 한국 남동해안에 나타나는 연안 용승에 비해 유량이 100배 이상 크게 나타났다. 이와 같이 구조물에 의해 발생하는 상승류는 하계 저층에 존재하는 고농도의 영양염을 표층으로 상승시켜 주변해역의 기초생산량을 증가 시키는 역할을 가능하게 한다.

Interleukin-$32{\gamma}$ Transgenic Mice Resist LPS-Mediated Septic Shock

  • Kim, Sun Jong;Lee, Siyoung;Kwak, Areum;Kim, Eunsom;Jo, Seunghyun;Bae, Suyoung;Lee, Youngmin;Ryoo, Soyoon;Choi, Jida;Kim, Soohyun
    • Journal of Microbiology and Biotechnology
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    • 제24권8호
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    • pp.1133-1142
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    • 2014
  • Interleukin-32 (IL-32) is a cytokine and inducer of various proinflammatory cytokines such as $TNF{\alpha}$, IL-$1{\beta}$, and IL-6 as well as chemokines. There are five splicing variants (${\alpha}$, ${\beta}$, ${\gamma}$, ${\delta}$, and ${\varepsilon}$) and IL-$32{\gamma}$ is the most active isoform. We generated human IL-$32{\gamma}$ transgenic (IL-$32{\gamma}$ TG) mice to express high level of IL-$32{\gamma}$ in various tissues, including immune cells. The pathology of sepsis is based on the systemic inflammatory response that is characterized by upregulating inflammatory cytokines in whole body, particularly in response to gram-negative bacteria. We investigated the role of IL-$32{\gamma}$ in a mouse model of experimental sepsis by using lipopolysaccharides (LPS). We found that IL-$32{\gamma}TG$ mice resisted LPS-induced lethal endotoxemia. IL-$32{\gamma}$ reduced systemic cytokines release after LPS administration but not the local immune response. IL-$32{\gamma}TG$ increased neutrophil influx into the initial foci of the primary injected site, and prolonged local cytokines and chemokines production. These results suggest that neutrophil recruitment in IL-$32{\gamma}TG$ occurred as a result of the local induction of chemokines but not the systemic inflammatory cytokine circulation. Together, our results suggest that IL-$32{\gamma}$ enhances an innate immune response against local infection but inhibits the spread of immune responses, leading to systemic immune disorder.