• Title/Summary/Keyword: general circulation

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Seasonal Variation of Global Volume Transport Calculated from an Ocean General Circulation Model

  • Jang, Chan-Joo;Noh, Yign;Kim, Cheol-Ho
    • Ocean and Polar Research
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    • v.24 no.1
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    • pp.1-18
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    • 2002
  • Seasonal variation in global transport calculated from an ocean general circulation model (OGCM) has been assessed through the comparison with observational estimates. The OGCM based on the GFDL MOM1.1 has honzontal grid interval of 10 and 21 verticle levels, and was integrated for 31 years forced by climatological wind stress, freshwater flux, and heat flux with restoring. General features of the world ocean circulation are well reproduced, which include the western boundary currents such as the Kuroshio and the Agulhas Current, the Equatorial Current system, the Antarctic Circumpolar Current, and the Weddell Sea gyres. Also well resolved is the remarkable seasonal variation in the depth-integrated flows in the northern Indian Ocean due to the monsoonal wind. Monthly variation is found to be dominant in the transport of the Antarctic Circumpolar Current through the Drake Passage in accordance with observational estimates. It has been shown that the mid-latitude depth-integrated flows obey the Sverdrup relation, except for some regions such as continental shelf regions where the interaction between stratification and bottom topography is critical.

Numerical Study on the Role of Sea-ice Using Ocean General Circulation Model (해양대순환모형을 이용한 해빙의 역할에 관한 수치실험 연구)

  • Lee, Jin-Ah;Ahn, Joong-Bae
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.6 no.4
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    • pp.225-233
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    • 2001
  • In order to find out the role of sea-ice in the climate system, a thermodynamic sea-ice model has been developed and included in the ocean general circulation model, MOM2, for the construction of OGCM/sea-ice coupled model in this study. By using the model developed, seasonal mean sea-ice distribution has been simulated, first of all. The role of sea-ice in the sense of large scale ocean circulation has been studied by comparing the results of OGCM/sea-ice coupled model experiment with OGCM-standalone experiment. At the same time, the coupled model has been verified by comparing and analysing the results of the other models and observation. The coupled model has reasonably simulated the overall seasonal distribution of sea-ice in the high latitudes of both hemispheres. In the comparative analysis between the OGCM/sea-ice coupled and OGCM-standalone experiments, the sea-ice is playing important roles on maintaining not only the distributions of temperature and salinity in high latitudes of both hemispheres, but also the meridional ocean circulation associated with south ocean cell, southern hemisphere cell and zonal ocean circulation such as a circum-polar current.

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Assessment of Future Water Circulation Rate in Dodang Watershed under Climate Change (기후변화에 따른 도당천 유역 미래 물순환율 평가)

  • Kwak, Jihye;Hwang, Soonho;Jun, Sang Min;Kim, Seokhyeon;Choi, Soon Kun;Kang, Moon Seong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.62 no.4
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    • pp.99-110
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    • 2020
  • The objective of this study is to analyze the trend of changes in the water circulation rates under climate change by adopting the concept of WCR defined by the Ministry of Environment. With the need for sound water circulation recovery, the MOE proposed the idea of WCR as (1-direct flow/precipitation). The guideline for calculating WCR suggests the SCS method, which is only suitable for short term rainfall events. However, climate change, which affects WCR significantly, is a global phenomenon and happens gradually over a long period. Therefore, long-term trends in WCRs should also be considered when analyzing changes in WCR due to climate change. RCP (Representative Concentration Pathway) 4.5 and 8.5 scenarios were used to simulate future runoff. SWAT (Soil and Water Assessment Tool) was run under the future daily data from GCMs (General Circulation Models) after the calibration. In 2085s, monthly WCR decreased by 4.2-9.9% and 3.3-8.7% in April and October. However, the WCR in the winter increased as the precipitation during the winter decreased compared to the baseline. In the aspect of yearly WCR, the value showed a decrease in most GCMs in the mid-long future. In particular, in the case of the RCP 8.5 scenario, the WCR reduced 2-3 times rapidly than the RCP 4.5 scenario. The WCR of 2055s did not significantly differ from the 2025s, but the value declined by 0.6-2.8% at 2085s.

A Study on the Change of Form Type in General Hospital (국내 종합병원의 형태 유형 변화에 관한 연구)

  • Kim, Eun-Seok;Yang, Nae-Won
    • Korean Institute of Interior Design Journal
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    • v.23 no.6
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    • pp.195-203
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    • 2014
  • This study selects factors affecting form type of hospital architecture by considering studies and references on hospital architecture type in korea and other countries in general. Also this study classifies general hospitals chronologically and analyzes type change of general hospitals in relation with periodic change of healthcare environment. Through this, this study aims to analyze chronological change of general hospitals' form type and provide the current of hospital architecture's general type. The form type classification of this study is classification according to the form of ward, classification according to the relationship between ward and D.T.D(Diagnostic and Treatment department), classification according to the relationship between O.P.D(Out Patient department) and D.T.D, classification according to the rate of centralization, classification according to the circulation system. The form type of ward changed from plate type to tower type, and the circulation system of ward changed from middle corridor to double corridor, the number of Team Nursing chaged from 1 to 2 in 1990. On the other hand the chage of others classifications took place from 1990' to 2010'. It is judged that this overall change is appeared by a change from an inpatien-oriented system to an outpatient-oriented system followed by an increase in number of outpatients, an increase in amenities in ground floor and adoption of healing environment for patients and visitors.

Activation of Fibrinolytic System during Open Heart Surgery (개심술중 섬유소융해계의 활성화에 관한 연구)

  • Park, Lee-Tae;Seo, Gyeong-Pil;Lee, Jeong-Sang
    • Journal of Chest Surgery
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    • v.22 no.4
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    • pp.525-547
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    • 1989
  • Hemorrhagic tendency observed in open heart surgery patients has been attributed, among other causes, to increased fibrinolytic activity during extracorporeal circulation. But the exact mechanism of enhanced fibrinolytic activity which occurs during extracorporeal circulation is still unknown. So, we studied and compared the changes of parameters of fibrinolytic and protein C system according to time obtained from the plasma of 31 adult open heart surgery patients[EGG group] and 10 adult general thoracic surgery patients[control group], in order to confirm the hypothesis that the activated protein C system might affect the fibrinolytic system during extracorporeal circulation. In ECC group, the nature of the enhanced fibrinolytic activity that evolved during extracorporeal circulation was characterized by significant increase in fibrin degradation products[P < 0.01] and significant decrease in plasminogen and alpha2-antiplasmin[P < 0.05, P < 0.01] in spite of adequate amount of heparin administration. These changes were most pronounced in the early phase of extracorporeal circulation and normalized after termination of extracorporeal circulation. The results of these observations were the same after volume correction with the value of hematocrit. The change of volume corrected protein C ratio during extracorporeal circulation revealed similar pattern to those of plasminogen and alpha2-antiplasmin [P < 0.01], but volume corrected ratio of free protein S showed significant increase after the commencement of extracorporeal circulation then decreased after extracorporeal circulation. Although the above mentioned changes occur similarly in both bubble type oxygenator-used and membrane oxygenator-used patients groups, but the degree of decrease was more severe in membrane oxygenator-used patients group [P < 0.01] and showed much slower recovery to reach to the preextracorporeal circulation level. These results confirm the hypothesis that the enhanced fibrinolysis during extracorporeal circulation might be caused by the activation of protein C system and the activation is possibly linked to the appearance of thrombin from contact activation of blood after wide exposure to the synthetic surfaces of extracorporeal circuit. Key words: Extracorporeal circulation, Enhanced fibrinolysis, Protein C system.

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A Comparison of Two Vertical-Mixing Schemes on the Simulation of the Mixed Layer Depth and Upper Ocean Temperature in an Ocean General Circulation Model (두 가지 연직혼합방안에 따른 해양대순환모형 혼합층깊이 및 상층수온 모사 민감도 비교)

  • Yi, Dong-Won;Jang, Chan Joo;Yeh, Sang-Wook;Park, Taewook;Shin, Ho-Jeong;Kim, Donghoon;Kug, Jong-Seong
    • Ocean and Polar Research
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    • v.35 no.3
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    • pp.249-258
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    • 2013
  • Vertical and horizontal mixing processes in the ocean mixed layer determine sea surface temperature and temperature variability. Accordingly, simulating these processes properly is crucial in order to obtain more accurate climate simulations and more reliable future projections using an ocean general circulation model (OGCM). In this study, by using Modular Ocean Model version 4 (MOM4) developed by Geophysical Fluid Dynamics Laboratory, the upper ocean temperature and mixed layer depth were simulated with two different vertical mixing schemes that are most widely used and then compared. The resultant differences were analyzed to understand the underlying mechanism, especially in the Tropical Pacific Ocean where the differences appeared to be the greatest. One of the schemes was the so-called KPP scheme that uses K-Profile parameterization with nonlocal vertical mixing and the other was the N scheme that was rather recently developed based on a second-order turbulence closure. In the equatorial Pacific, the N scheme simulates the mixed layer at a deeper level than the KPP scheme. One of the reasons is that the total vertical diffusivity coefficient simulated with the N scheme is ten times larger, at maximum, in the surface layer compared to the KPP scheme. Another reason is that the zonal current simulated with the N scheme peaks at a deeper ocean level than the KPP scheme, which indicates that the vertical shear was simulated on a larger scale by the N scheme and it enhanced the mixed layer depth. It is notable that while the N scheme simulates a deeper mixed layer in the equatorial Pacific compared to the KPP scheme, the sea surface temperature (SST) simulated with the N scheme was cooler in the central Pacific and warmer in the eastern Pacific. We postulated that the reason for this is that in the central Pacific atmospheric forcing plays an important role in determining SST and so does a strong upwelling in the eastern Pacific. In conclusion, what determines SST is crucial in interpreting the relationship between SST and mixed layer depth.

A Study on the Development of Universal Design Checklist in the Public Space of the General Hospitals by the Analysis of Users' Types - Following the Orthopedic Outpatients' Circulation - (사용자 유형분석을 통한 종합병원 공용공간의 유니버설 디자인 체크리스트 개발에 관한 연구 - 정형외과 외래진료 환자의 동선을 따라서 -)

  • Lee, Eun-Jin;Choi, Sang-Hun
    • Korean Institute of Interior Design Journal
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    • v.15 no.2 s.55
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    • pp.13-20
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    • 2006
  • The Universal Design is introduced as the universal principle to satisfy people's requirements for various environment. The public space of general hospitals should be designed with consideration of specific requirements of customers. The purpose of our research is to develop and propose the Universal Design checklist which considers the circulation in the public space. We investigated that the consideration for universal design was lacked by actual survey with the checklist made according to 'The law for improving convenience of the disabled, old people and pregnant women'. Furthermore, we found the problems of the checklist. We correct the checklist considering the measurements of the user's body and action. In addition, we propose the Universal Design Checklist by adding the new references in the article about the installation.

The Pedestrian Integrated Circulation System in Mixed-use Building based on User Behavior (이용자 행태 기반 복합건축 보행자 통합동선계획)

  • Lee, Jin-Kyoung;Kim, Chan-Ju
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.35 no.12
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    • pp.21-29
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    • 2019
  • The purpose of the study is to be the pedestrian integrated circulation system of malling route and the third route in Mixed-use Building based on User Behavior. The study has performed by the following approaches: Initially, literature reviews are performed related to a pedestrian route by user in mixed-use building. Second, general and stroller users moving route are analyzed based on the outcome of the case study. Finally, the study develops the efficient pedestrian integrated circulation system of malling route and the third route in Mixed-use Building. According to the study, the following conclusions were made: First, An integrated plan for escalators and EVs, which are accessible to both users and strollers, is needed. Second, The entrance automatic door and circulation elements should be connected for continuous move by the stroller users. Finally, The circulation system of complex buildings should be a simple spatial structure and route plan that users can easily recognize.

A study on the atmospheric response to a SST anomaly over the Equatorial Eastern Pacific Ocean with the horizontally fine resolution AGCM (수평조밀격자 GCM을 이용한 적도 태평양상의 SST anomaly에 대한 대기 반응 연구)

  • Moon, Sung-Eui;Ahn, Joong-Bae;Kim, Yoo-Keun
    • Journal of Environmental Science International
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    • v.4 no.5
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    • pp.403-411
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    • 1995
  • The atmospheric responses to a Sea Surface Temperature Anomaly(SSTA) over the equatorial eastern Pacific Ocean have been investigated using the horizontally fine resolution model based on OSU 2-layer Atmospheric General Circulation Model(AGCM). The SSTAS daring the peak phase of 1982-83 El Nino have been applied to the model as the boundary conditions of the experiment. The model simulates the eastward movement of the rising branch of the Walker circulation. That is, the major features associated with the El Nino such as the increase of the precipitation rate over the center of the Pacific and decrease over the Indonesia, and the 500hPa geopotential height anomaly in the middle latitude are properly describes in the fine resolution model experiment. The model results indicate that this horizontally fine resolution UM can successfully simulate the ENSO anomalies and be more effectivelly used for the study of the climate and the climate changes.

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A Study on the Spatial Composition Strategy in the Remodeling of General Hospitals - Focused on the Departmental Relocation and Circulation System - (국내 종합병원의 리모델링에 나타난 공간구성방안에 관한 연구 - 부문별 재배치 및 동선연결방안을 중심으로 -)

  • Kim Ha-Jin;Yang Nae-Won
    • Korean Institute of Interior Design Journal
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    • v.13 no.6
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    • pp.123-131
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    • 2004
  • The hospitals built In the seventies and eighties have gone through many different extensions and renovations. However, as there had been no prior projections of the future extensions, irrational processes in terms of interdepartmental functional relocations and space availability have recurred. As well, areas and departments are located in several wings, which bring about a decrease in interdepartmental functional linkage, causing a lot of confusion and trouble in hospital management. Through this research we acquire concluding remarks. 1) To restore functional linkage in the whole hospital, strategy of interdepartmental relocation with the clinic-in-the clinic concept is the measure to minimize the problems of the increase in interdepartmental functional linkage since the clinic-in-the clinic concepts minimize circulation and maximizes efficiency of hospital management by making all the dispersed wings as professional as possible. 2) The measure of smooth circulation in order to resolve the problems of patients' difficulty in identifying directions and in decrease in staff's work performance, which arises from the extensions without considering the traffic systems of the whole hospital involves introduction of linear circulation systems in which connections between departments or areas can be made centering main axes of circulation. It is also a responsive measure to enhance the functional linkage between buildings and efficiency of patient's ease in identification of directions.