• 제목/요약/키워드: general circulation

검색결과 489건 처리시간 0.029초

수자원 영향평가를 위한 기후변화 시나리오의 불확실성 평가 (Uncertainties estimation of AOGCM-based climate scenarios for impact assessment on water resources)

  • 박이형;임은순;권원태;이은정
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 2005년도 학술발표회 논문집
    • /
    • pp.138-142
    • /
    • 2005
  • The change of precipitation and temperature due to the global. warming eventually caused the variation of water availability in terms of potential evapotranspiration, soil moisture, and runoff. In this reason national long-term water resource planning should be considered the effect of climate change. Study of AOGCM-based scenario to proposed the plausible future states of the climate system has become increasingly important for hydrological impact assessment. Future climate changes over East Asia are projected from the coupled atmosphere-ocean general circulation model (AOGCM) simulations based on Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A2 and B2 scenarios using multi-model ensembles (MMEs) method (Min et al. 2004). MME method is used to reduce the uncertainty of individual models. However, the uncertainty increases are larger over the small area than the large area. It is demonstrated that the temperature increases is larger over continental area than oceanic area in the 21st century.

  • PDF

Study of aerosol-cloud interaction phenomena from satellite remote sensing and climate modeling

  • Nakajima, Teruyuki;Higurashi, Akiko;Kawamoto, Kazuaki;Okamoto, Hajime;Takemura, Toshihiko;Kuroda, Shunsuke
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
    • /
    • pp.100-102
    • /
    • 1999
  • We have analyzed AVHRR global data set for obtaining aerosol and cloud microphysical parameters, i. e., optical thickness and size index of particle polydispersions. From the results, it is found that the cloud optical thickness increases with increasing aerosol column number, which seems to be caused mainly by decreasing cloud particle radius, The cloud liquid water path was observed to be relatively constant without a significant dependence on the aerosol number. Further comparison of the satellite results with a general circulation model simulation.

  • PDF

저 누드센 영역에서 다중 유체구 주위의 유동장 해석 (Analysis of Flow Field around Multiple Fluid Spheres in the Low Knudsen Number Region)

  • 정창훈;이규원
    • 한국대기환경학회지
    • /
    • 제19권6호
    • /
    • pp.733-743
    • /
    • 2003
  • The flow field in multiple fluid sphere systems was studied analytically. The expanded zero vorticity cell model based on Kuwabara's theory (1959) was applied and the effects of gas slippage at the collecting surface were considered. Also, the solid sphere system was extended to fluid sphere including the effects of the induced internal circulation inside the liquid droplet spheres or gas bubble systems. As a result, the obtained analytic solution was converged to the existing solutions for flow field around solid and bubble sphere systems with proper boundary conditions. Based on the resolved flow field, the terminal velocity around the collecting fluid spheres was obtained. Subsequently, this study evaluated the most general solution for flow field around the multiple fluid sphere systems. The obtained flow field in multiple fluid sphere could be used as a fundamental consideration of wet scrubber design and devices for removing particles by fluid-fluid interactions.

대기/해양 접합 GCM을 이용한 지구 온난화의 추정 (Estimation of Global Warming by Coupled Atmosphere-Ocean GCM)

  • 김정우;박지업
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 2000년도 춘계 학술대회논문집
    • /
    • pp.14-19
    • /
    • 2000
  • A coupled general circulation model (GCM) of the global atmosphere, oceans and lands is used for finding the future climate at times of doubled carbon dioxide concentration (DCDC) of the atmosphere. Two runs of the model were made in order to find the future change. Global changes at times of DCDC may be characterized by a global warmig of $1.4^{\circ}C$, a $3\%$ global precipitation increase, and an increase in the surface available water (SAW) over the global land among others. The estimated increase in SAW over the land implies that river discharge is likely to increase with increased chance of severe weather as a result of the future global warming.

  • PDF

승모판막 치환의 조기 성적;158 임상보고례 (Early Results of Mitral Valve Replacement - Clinical analysis of 158 cases -)

  • 김한용
    • Journal of Chest Surgery
    • /
    • 제25권9호
    • /
    • pp.976-981
    • /
    • 1992
  • The results of the clinical observations on the 158 cases of the mitral valvular heart disease treated at the Department of Thoracic and Cardiovascular Surgery, Masan Koryo General Hospital from June, 1986 to December, 1991 were as follows; 1. There were 50 men and 108 women with sex ratio 1: 2.2. 2. The age of patient varied widely from 13 years to 65years. 3. The preoperative functional level accoridng to the NYHA classification were class II, III, IV in 18%, 67%, 15%. 4. All 158 patients were operated on under direct vision using extracorporeal circulation, mitral valve replacement in 118 cases, mitral and aortic valve replacement 40 cases. 5. The follow up period was between 2 months and 65 months postoperatively. [mean 30.1 months] 6. The early operative motality was 5.7%[9 cases], late motality was 4%[6 cases]. 7. The cardiothoracic ratio in the chest X-ray decreased at the 6th month postoperation. [pre-op: 0.60$\pm$0.07, post-op: 0.56$\pm$0.06 p<0.01]

  • PDF

전페정맥 이상환류 (TAPVD)의 치험 1례 (Total Anomalous Pulmonary Venous Drainage with A.S.D.)

  • 오재상;박영관;김근호
    • Journal of Chest Surgery
    • /
    • 제13권2호
    • /
    • pp.110-117
    • /
    • 1980
  • This is a case report of total anomalous pulmonary venous drainage with Atrial septal defect, which was corrected surgically by intracardiac procedure under total cardiopulmonary bypass. This 9 years old girl, she complained mild cyanosis, exertional dyspnea, and frequent upper respiratory infection from 3 months age. The chest X-ray showed cardiomegaly and a "snow man appearance", she has systolic murmur with splitting of S2. The diagnosis was confirmed with right heart catheterization, the catheter was reached to right pulmonic vein passed through right atrium, right superior vena cava, innominate vein, left superior vena cava, and common venous trunk. On 28th, Dec. 1979, an anastomosis between common pulmonary venous trunk and left atrium, Pericardial patch closure of ASD, and ligation of left superior vena cava were performed with Extra-corporeal circulation. The postoperative course was uneventful and discharged with excellent general condition.Total Anomalous Pulmonary Venous Drainage with A.S.D. with A.S.D.

  • PDF

A Study of the Momentum Balance in the High-Latitude Lower Thermosphere Based on the Ncar-Tiegcm: Dependence on the Interplanetary Magnetic Field (IMF)

  • Kwak, Young-Sil;Ahn, Byung-Ho;Arthur D. Richmond
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
    • /
    • 한국우주과학회 2004년도 한국우주과학회보 제13권1호
    • /
    • pp.70-70
    • /
    • 2004
  • Lower thermospheric winds are forced primarily by non-uniform solar heating, atmospheric tides and other waves coming from below, and energy and momentum forcing associated with high-latitude magnetosphere-ionosphere coupling, particularly ion drag and Joule heating. To understand the physical processes that control the thermospheric dynamics, we quantify the momentum forces that are mainly responsible for maintaining the high-latitude lower thermospheric wind system and examine the resulting momentum balance with the aid of the Thermosphere-Ionosphere Electrodynamics General Circulation Model (NCAR-TIEGCM) developed by the National Center for Atmospheric Research. (omitted)

  • PDF

기후변화 대응 에어러솔 연구 발전을 위한 정책 연구 (Policy Studies for Advancing Aerosol Research on Climate Change in Korea)

  • 김지영;이용섭;신임철
    • 대기
    • /
    • 제20권1호
    • /
    • pp.49-61
    • /
    • 2010
  • Atmospheric aerosols play a crucial role for changing climate, resulting in a wide range of uncertainty for future climate prediction. In this paper we review current international research status and trend of climate-related aerosol science. There have been carried out a number of campaigns (including ACE-Asia, TRACE-P, ABC, and so on) and special experiments with some modeling studies over Korea, East Asia, and the Northwestern Pacific to characterize the various properties (physical, chemical, optical, and radiative) of Asian aerosols and evaluate their climate forcing impacts. But some parts of the aerosol research may need to be improved, advanced, or newly launched. Especially, a chemical transport model (CTM) embedded by a general circulation model (GCM) should be developed by the national scientific community with a high research priority, actively collaborating with international community in order to estimate direct and indirect global radiative forcing due to anthropogenic and natural aerosols.

Life table method을 이용한 자동차 생산기간의 생존분석 (Life table method of survival analysis using the automobile production period)

  • 김성제;조재립
    • 대한안전경영과학회:학술대회논문집
    • /
    • 대한안전경영과학회 2009년도 춘계학술대회
    • /
    • pp.531-539
    • /
    • 2009
  • The environment of automobile industry in the world is rapidly changing. It is changing of high oil price, technology, environment and construction of competition by newly rising an economic district. Automobile company is focusing on three issue because they want to reinforce competition of automobile industry in the world. That is innovation of production profit management through quality management and Lean. Chance of success is separated in R&D, providing distribution, manufacture, distribution, selling in automobile industry. Emphasis on development process, distribution process, manufacture process, circulation and selling process for strengthening the competitiveness and guarantee. In this thesis, we try to analysis the data set period of automobile production by using survival analysis. While using mean comparison of general statistics commit mistakes, survival analysis can used for including censored data in order to heighten analysis efficiency.

  • PDF

Tribological diagnostics of machinery

  • Myshkin, N.K.
    • 한국윤활학회:학술대회논문집
    • /
    • 한국윤활학회 1990년도 제11회 학술강연회초록집
    • /
    • pp.7-31
    • /
    • 1990
  • Tribologicsl diagnostics as the ensemble of means and methods of continuous monitoring of the state of friction characteristics of moving junctions is playing an ever important part in the development of friction, lubrication, and wear theory end practice. The scheme presenting the main areas of tribological diagnostics is given in Fig. I. This growing part of TD is determined by the general tendency of modern technology, expressed in an attempt to organically combine the functions of measuring, evaluating,and predicting the parameters and characteristics of the processee taking place in the operating device. The logical result of this integration in future is the closed system correcting its operation in accordance with sn established program. Unfortunately, tribotechnicsl devices are still very far from such an ideal system at the present time. While in the friction assemblies with hydrodynamic lubrication it is possible in the first approximation to realize feed-backs in the lubricant circulation system with the aid of monitoring of the pressure, temperature and filtration, in the systems operating without lubrication and with boundary lubricetion even the process of selection of the diagnostic parameters has not been completed.

  • PDF