• Title/Summary/Keyword: Integrated circulation model

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Modeling Paddlewheel-Driven Circulation in a Culture Pond (축제식 양식장에서 수차에 의한 순환 모델링)

  • KANG Yun Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.6
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    • pp.643-651
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    • 2001
  • Paddlewheel-driven circulation in a culture pond has been simulated based on the depth integrated 2 dimensional hydrodynamic model. Acceleration by paddlewheel is expressed as shaft force divided by water mass discharged by paddlewheel blades. The model has been calibrated and applied to culture ponds as following steps:- i) The model predicted velocities at every 10 m along longitudinal direction from the paddlewheel. The model was calibrated comparing the results with the measured values at mass correction factor $\alpha$ and dimensionless eddy viscosity constant $\gamma$, respectively, in a range $15\~20$ and 6. ii) Wind shear stress was simulated under conditions of direction $0^{\circ}C,\;90^{\circ}C\;and\;180^{\circ}C$ and speed 0.0, 2.5, 5.0 and 7.5 m/s. Change rate of current speed was <$1\%$ at wind in parallel or opposite direction to the paddlewheel-driven jet flow, while $4\%$ at orthogonal angle. iii) The model was then applied to 2 culture ponds located at the Western coast of Korea. The measured and predicted currents for the ponds were compared using the regression analysis. Analysis of flow direction and speed showed correlation coefficients 0.8928 and 0.6782 in pond A, 0.8539 and 0.7071 in pond B, respectively. Hence, the model is concluded to accurately predict circulation driven by paddlewheel such that it can be a useful tool to provide pond management strategy relating to paddlewheel operation and water quality.

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Study on the Angular Momentum of Axisymmetric Tropical Cyclone in the Developing Stage (발달 단계의 축대칭 열대저기압의 각운동량에 관한 연구)

  • Kang, Hyun-Gyu;Cheong, Hyeong-Bin
    • Atmosphere
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    • v.23 no.1
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    • pp.1-11
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    • 2013
  • The angular momentum transport of an idealized axisymmetric vortex in the developing stage was investigated using the Weather Research and Forecast (WRF) model. The balanced axisymmetric vortex was constructed based on an empirical function for tangential wind, and the temperature, geopotential, and surface pressure were obtained from the balanced equation. The numerical simulation was carried out for 6 days on the f-plane with the Sea Surface Temperature (SST) set as constant. The weak vortex at initial time was intensified with time, and reached the strength of tropical cyclone in a couple of days. The Absolute Angular Momentum (AAM) was transported along with the secondary circulation of the vortex. Total AAM integrated over a cylinder of radius of 2000 km decreased with simulation time, but total kinetic energy increased rapidly. From the budget analysis, it was found that the surface friction is mainly responsible for the decrease of total AAM. Also, contribution of the surface friction to the AAM loss was about 90% while that of horizontal advection was as small as 8%. The trajectory of neutral numerical tracers following the secondary circulation was presented for the Lagrangian viewpoint of the transports of absolute angular momentum. From the analysis using the trajectory of tracers it was found that the air parcel was under the influence of the surface friction continuously until it leaves the boundary layer near the core. Then the air parcel with reduced amount of angular momentum compared to its original amount was transported from boundary layer to upper level of the vortex and contributed to form the anti-cyclone. These results suggest that the tropical cyclone loses angular momentum as it develops, which is due to the dissipation of angular momentum by the surface friction.

A Study on Information Revitalization Plans of Integrated Agriculture Information System (농업 종합 정보 시스템의 제안과 활성화 방안에 관한 연구)

  • Cha Jin-Man;Kang Min-Soo;Park Teoun-Sik
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.6
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    • pp.991-997
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    • 2006
  • Agriculture is usually the basis of a society, as well as the solution of dietary life. However, compared to other fields in which information-oriented system is rapidly accomplished, information system of agriculture certainly has slow growth since agriculture deals with a living thing. In addition, since government bodies related to filming have faced the difficulty of information system, they have tried establishing independent information system. The current agriculture-informationizing system can be considered as Agricultural Outlook Information System, Integrated agricultural marketing Information System and Outlook & Agricultural Statistics Information System but these systems are not effectively operated contrary to rut expectation, which$\sim\sim\sim$. Actually, there are some problems of bothinvestment duplicated and management by each independent government body, as well as Korea Rural Economic Institute-Commodity Model improper to real situation. In this paper, Agricultural Outlook Information, Integrated agricultural marketing Information, and Outlook h Agricultural Statistics Information System independently operated are integrated; Circulation Control, Technical Support, and integrated Database system are established; new integrated agricultural information system and various kinds of measures for activation of this system are suggested.

Development and Application of the Backward-tracking Model Analyzer to Track Physical and Chemical Processes of Air Parcels during the Transport (대기오염물질의 이동경로상 물리화학적 변화 추적을 위한 Backward-tracking Model Analyzer 방법론 마련)

  • Bae, Minah;Kim, Hyun Cheol;Kim, Byeong-Uk;Kim, Soontae
    • Journal of Korean Society for Atmospheric Environment
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    • v.33 no.3
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    • pp.217-232
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    • 2017
  • An Eulerian-Lagrangian hybrid modeling system to analyze physical and chemical processes during the transport of air parcels was developed. The Backward-tracking Model Analyzer (BMA) was designed to take advantages of both Eulerian and Lagrangian modeling approaches. Simulated trajectories from the National Oceanic and Atmospheric Administration HYSPLIT model were combined with the US Environmental Protection Agency Community Multi-scale Air Quality (CMAQ)-simulated concentrations and additional diagnostic analyses. In this study, we first introduced a generalized methodology to seamlessly match polylines (HYSPLIT) and threedimensional polygons (CMAQ), which enables mass-conservative analyses of physio-chemical processes of transporting air parcels. Two applications of the BMA were conducted: (1) a long-range transport case of pollutant plume across the Yellow Sea using CMAQ Integrated Process Rate analyses, and (2) a domestic circulation of pollutants within (and near) the South Korea based on the sulfate tracking analyzer. The first episode demonstrated a secondary formation of nitrate and ammonium during the transport over the Yellow Sea while sulfate is mostly transported after being formed over the China, and the second episode demonstrated a dominant impact of boundary condition with active sulfate formation from gas-phase oxidation near the Seoul Metropolitan Area.

Radiative Role of Clouds on the Earth Surface Energy Balance (지표 에너지 수지에 미치는 구름의 복사 역할)

  • Hong, Sung-Chul;Chung, Ii-Ung;Kim, Hyung-Jin;Lee, Jae-Bum;Oh, Sung-Nam
    • Journal of Environmental Science International
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    • v.16 no.3
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    • pp.261-267
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    • 2007
  • In this study, the Slab Ocean Model (SOM) is coupled with an Atmospheric General Circulation Model (AGCM) which developed in University of Kangnung based on the land surface model of Biosphere-Atmosphere Transfer Scheme (BATS). The purposes of this study are to understand radiative role of clouds considering of the atmospheric feedback, and to compare the Clouds Radiative Forcing (CRF) come from the analyses using the clear-cloud sky method and CGCM. The new CGCM was integrated by using two sets of the clouds with radiative role (EXP-A) and without radiative role (EXP-B). Clouds in this two cases show the negative effect $-26.0\;Wm^{-2}$ of difference of radiation budget at top of atmosphere (TOA). The annual global means radiation budget of this simulation at TOA is larger than the estimations ($-17.0 Wm^{-2}$) came from Earth Radiation Budget Experiment (ERBE). The work showed the surface negative effect with $-18.6 Wm^{-2}$ in the two different simulations of CRF. Otherwise, sensible heat flux in the simulation shows a great contribution with positive forcing of $+24.4 Wm^{-2}$. It is found that cooling effect to the surface temperature due to radiative role of clouds is about $7.5^{\circ}C$. From this study it could make an accurate of the different CRF estimation considering either feedback of EXP-B or not EXP-A under clear-sky and cloud-sky conditions respectively at TOA. This result clearly shows its difference of CRF $-11.1 Wm^{-2}$.

오행침자법(五行鍼刺法) 원리 및 임상응용에 관한 연구 - II 임상응용에 관한 연구

  • Ahn, Chang-Beohm;Min, Young-Kwang;Kim, Jeong-Eun;Moon, Hyuck-Chol;Song, Chun-Ho;Lee, Jang-Cheon;Shin, Sang-Woo
    • Journal of Pharmacopuncture
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    • v.11 no.3
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    • pp.33-45
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    • 2008
  • Objective: To review the clinical basis of the Sa-Ahm 5 Element acupuncture originated about 360 years ago, papers and books were researched. Methods: Total of 58 books and papers ranging from ancient Huang Di nei jing to modern Bio Medical Acupuncture for Pain Management were investigated to study the clinical practice of it. Results: It could be practiced differently depending upon the viewpoints of diagnosis. They are ranging from theories of the greater-less of Yin and Yang, 7 emotions, organs- visceras, 8 diagnostic criteria, and pulse diagnosis to meridian circulation. Conclusions: It needs to be set clinical guidelines by which to practice Sa-Ahm acupuncture though it is nowadays mostly-used method in accordance with practitioner's viewpoints.

Characteristics of the Gross Moist Stability in the Tropics and Its Future Change (열대 지역 Gross Moist Stability 특징 분석 및 미래 변화)

  • Kim, Hye-Won;Seo, Kyong-Hwan
    • Atmosphere
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    • v.24 no.2
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    • pp.141-150
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    • 2014
  • This study investigates the characteristics of the Gross Moist Stability (GMS) over the tropics. The GMS summarizes the relationship between large-scale entropy forcing due to radiation and surface fluxes and the response of smaller-scale convection. The GMS is able to explain both to where moist entropy is advected by the atmospheric circulation and how deep the moisture flux convergence is in the tropical region. In the deep convective region, positive GMS appears over the warm pool region due to the strong column-integrated moisture convergence and the ensuing export of moist entropy to the environment. The vertical advection of moist entropy dominates over the horizontal advection in this region. Meanwhile, over the eastern tropical ITCZ region, which is characterized by shallow convective area, import of moist entropy by horizontal winds is dominant compared to the vertical moist entropy advection. Future changes in the GMS are also examined using the 22 CMIP5 model simulations. A decrease in the GMS appears widely across the tropics, but its increase occurs over the western-central equatorial Pacific. It is evident that the increased GMS region corresponds to an increased region of precipitation, implying that strengthened convection in the future due to increased entropy forcing exports the enhanced moist energy to stabilize the environment.

Application of Bias-Correction and Stochastic Analogue Method (BCSA) to Statistically Downscale Daily Precipitation over South Korea (남한지역 일단위 강우량 공간상세화를 위한 BCSA 기법 적용성 검토)

  • Hwang, Syewoon;Jung, Imgook;Kim, Siho;Cho, Jaepil
    • Journal of The Korean Society of Agricultural Engineers
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    • v.63 no.6
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    • pp.49-60
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    • 2021
  • BCSA (Bias-Correction and Stochastic Analog) is a statistical downscaling technique designed to effectively correct the systematic errors of GCM (General Circulation Model) output and reproduce basic statistics and spatial variability of the observed precipitation filed. In this study, the applicability of BCSA was evaluated using the ASOS observation data over South Korea, which belongs to the monsoon climatic zone with large spatial variability of rainfall and different rainfall characteristics. The results presented the reproducibility of temporal and spatial variability of daily precipitation in various manners. As a result of comparing the spatial correlation with the observation data, it was found that the reproducibility of various climate indices including the average spatial correlation (variability) of rainfall events in South Korea was superior to the raw GCM output. In addition, the needs of future related studies to improve BCSA, such as supplementing algorithms to reduce calculation time, enhancing reproducibility of temporal rainfall patterns, and evaluating applicability to other meteorological factors, were pointed out. The results of this study can be used as the logical background for applying BCSA for reproducing spatial details of the rainfall characteristic over the Korean Peninsula.

A Study on Aspects of Transmedial Enjoyment of Game Users (게임 사용자의 트랜스미디어적 향유 양상 연구)

  • Ahn, Jin-Kyoung
    • Journal of Convergence for Information Technology
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    • v.11 no.8
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    • pp.119-128
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    • 2021
  • This study defines the integrated game experience of game users that across internal and external media of game as the transmedia enjoyment of game. This study categorizes the cases and analyze features. Game users have four types of transmedial enjoyment. The expansion type is characterized by the user's desire to solve the uncertainty, and the transmission type is characterized by the emergence of alternative play spaces. In the permeation type and the circulation type, it is observed users participate more in the content can be re-contextualized and based on real world knowledge.

A Study on the Wayfinding Model of Outpatient Department in General Hospital (종합병원 외래진료부 진로인지계획 모형에 관한 연구)

  • Han, Gi-Jeung;Lee, Teuk-Koo
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.13 no.2
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    • pp.27-36
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    • 2007
  • Recently, hospital patients experience anxiety, confusion, and stress about wayfinding as the spacial layout and treatment circulatory system of hospitals have become complicated due to their oversized and complex structure. As part of finding a solution to the problem, this study seeks to examine what are the essential elements of the wayfinding planning of O.P.D. in general hospitals, to develop the model of wayfinding, and to suggest the methods of improving the wayfinding system. The research methods of this study adopted were literature review in wayfinding cognition, plan analysis of ten general hospitals, space analysis of these hospitals through space syntax, analysis of the system of visual-perceptual information through a field study, and analysis of surveys and follow-up surveys conducted to support the results. Based on these results, the proposals for finding decision points, providing the information, and developing a model planning are listed as follows. 1) The comprehensive understanding of O.P.D. spacial layout and the visual-perceptual information system is necessary to find the essential elements of wayfinding. 2) The decision points are found through the full understanding of spacial functions, circulation systems, and facility configuration, considering the spacial layout, the bound of the visual-perceptual information system, and the circulatory system. Furthermore, the information decision points could be confined by space syntax. 3) The checklist and color compound & color codes, developed through the planning of signage system and color system could be applied to the methods of providing the information. 4) The planning of wayfinding system according to the whole process of practices for outpatients was mentioned above. The system of visual-perceptual information developed through the process of this study should be integrated in the spacial layout of the whole O.P.D.

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