• 제목/요약/키워드: Map Flow analysis

검색결과 248건 처리시간 0.027초

Application of Grid-based Kinematic Wave Storm Runoff Model

  • Kim, Seong-Joon;Kim, Sun-Joo;Chae, Hyo-Seok
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2000년도 학술발표회 논문집
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    • pp.20-27
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    • 2000
  • The grid-based KlneMatic wave STOrm Runoff Modei (Kim, 1998; Kim, et al., 1998) which predicts temporal variation and spatial distribution of saturated overland flow, subsurface flow and stream flow was evaluated at two watersheds. This model adopts the single overland flowpath algorithm and simulates surface and/or subsurface water depth at each cell by using water balance of hydrologic components. The model programed by C-language uses ASCII-formatted map data supported by the irregular gridded map of the GRASS (Geographic Resources Analysis Support System) GIS and generates the spatial distribution maps of discharge, flow depth and soil moisture of the watershed.

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Improvement of the CCFL Model of the RELAP5/MOD3.2.2B Code in a Horizontal Pipe

  • Heo, Sun;No, Hee-Cheon;Chang, Kyung-Sung;Ha, Sang-Jun
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1999년도 춘계학술발표회요약집
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    • pp.115-115
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    • 1999
  • To demonstrate the applicability of RELAP5 to the prediction of the onset offlooding in the hot leg at the reflux condensation phase during mid-loop operation, numerical analysis is performed for the counter-current flow in a horizontal pipe with the inclined riser using the RELAP5/MOD3.2.2b code. It is found that the RELAP5, simulating the CCFL phenomena using interfacial friction along with the flow regime map in the horizontal pipe, produces unsatisfactory results. Under the CCFL condition, it is observed that large oscillation exists in the flow rate, void fraction, and etc. and the liquid flow rate is much lower than that predicted by the CCFL model measured in the experiment. The CCFL model of RELAP5 for the vertical volume is extended to the model for the horizontal and inclined volumes. The horizontal volume flow regime map and interfacial friction model coupled to the CCFL model are modified. And a new correlation developed from Kang's experiment is implemented to the CCFL model of RELAP5. With this modified RELAP5, the analysis of CCFL phenomena in the horizontal pipe and hot leg geometry is performed, and produces reasonable results in comparison with experimental data.

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STABILITY ANALYSIS OF BURSTING MODELS

  • Lee, Eui-Woo
    • 대한수학회지
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    • 제42권4호
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    • pp.827-845
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    • 2005
  • In this paper, we present a general method for the stability analysis of some bursting models. Our method is geometric in the sense that we consider a flow-defined return map defined on a section and determine when the map is a contraction. We find that there are three different stability types in the codimension-1 planar bursters.

공간예측모형에 기반한 산사태 취약성 지도 작성과 품질 평가 (Mapping Landslide Susceptibility Based on Spatial Prediction Modeling Approach and Quality Assessment)

  • 알-마문;박현수;장동호
    • 한국지형학회지
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    • 제26권3호
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    • pp.53-67
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    • 2019
  • The purpose of this study is to identify the quality of landslide susceptibility in a landslide-prone area (Jinbu-myeon, Gangwon-do, South Korea) by spatial prediction modeling approach and compare the results obtained. For this goal, a landslide inventory map was prepared mainly based on past historical information and aerial photographs analysis (Daum Map, 2008), as well as some field observation. Altogether, 550 landslides were counted at the whole study area. Among them, 182 landslides are debris flow and each group of landslides was constructed in the inventory map separately. Then, the landslide inventory was randomly selected through Excel; 50% landslide was used for model analysis and the remaining 50% was used for validation purpose. Total 12 contributing factors, such as slope, aspect, curvature, topographic wetness index (TWI), elevation, forest type, forest timber diameter, forest crown density, geology, landuse, soil depth, and soil drainage were used in the analysis. Moreover, to find out the co-relation between landslide causative factors and incidents landslide, pixels were divided into several classes and frequency ratio for individual class was extracted. Eventually, six landslide susceptibility maps were constructed using the Bayesian Predictive Discriminant (BPD), Empirical Likelihood Ratio (ELR), and Linear Regression Method (LRM) models based on different category dada. Finally, in the cross validation process, landslide susceptibility map was plotted with a receiver operating characteristic (ROC) curve and calculated the area under the curve (AUC) and tried to extract success rate curve. The result showed that Bayesian, likelihood and linear models were of 85.52%, 85.23%, and 83.49% accuracy respectively for total data. Subsequently, in the category of debris flow landslide, results are little better compare with total data and its contained 86.33%, 85.53% and 84.17% accuracy. It means all three models were reasonable methods for landslide susceptibility analysis. The models have proved to produce reliable predictions for regional spatial planning or land-use planning.

유전자 알고리즘을 이용한 가스터빈 엔진의 구성품 성능선도 생성에 관한 연구 (A Study on Component Map Generation of a Gas Turbine Engine Using Genetic Algorithms)

  • 공창덕;고성희
    • 한국추진공학회지
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    • 제8권3호
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    • pp.44-52
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    • 2004
  • 본 연구에서는 실험데이터와 유전자 알고리즘으로 압축기 성능선도를 생성하는 방법을 제안하였다. 다수의 실험을 통해 엔진의 성능 데이터를 획득하고 회전수에 따른 유량함수, 압력비, 효율의 함수관계를 3차 방정식으로 유도한 후 유전자 알고리즘을 이용하여 미계수를 구하여 압축기 성능선도를 생성하였다. 새롭게 생성한 압축기 성능선도를 이용하여 상용 성능해석 프로그램인 GASTURB로 정상상태 성능해석을 수행하여 검증데이터와 비교하였다.

모바일 상황에서 대화형 에이전트와 사용자의 대화 흐름도 도출 연구 (Study of deduction flow map on conversation toward the Embodied conversational agents in the Mobile Environment)

  • 최유정;조윤주;박수이
    • 한국HCI학회:학술대회논문집
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    • 한국HCI학회 2008년도 학술대회 1부
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    • pp.178-183
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    • 2008
  • 본 연구의 목적은 대화형 에이전트와 사용자 간의 대회를 분석하여 대화의 흐름도를 도출해 내는 것에 있다. 특히 본 연구에서는 대화에 대한 전반적인 요소 추출과 더불어 대화형 에이전트와 사용자 간에 발생할 수 있는 대화 유형까지 도출해 내어 대화형 에이전트의 대화 능력 향상에 기여하고자했다. 이를 위해 1대 1 개인 인터뷰를 실시하여 실제 대화형 에이전트와 사용자 간의 대화 데이터를 수집하고 기본적으로 질적 연구 방법론을 바탕으로 대화 분석론과 대화유형학을 참고하여 연구를 실시한 결과 층 6개의 대화 흐름도를 도출하였다. 특히 원활하지 않은 대화는 기존의 사람과 사람과의 대화에서는 찾아보기 힘든 대화이며 그 개수도 52개로 가장 많이 나타났다. 대화 방해 요소가 나타났을 경우 상대에 대한 적대감을 보이거나 대화를 교정하는 행위로 대화가 진행되었다. 본 연구는 포괄적인 대화형 에이전트와 사용자 간의 대회를 분석하여 그 유형을 알아냈다는 점에서 대화형 에이전트 개발자와 사용자, 서비스 제공자 모두에서 긍정적인 영향을 미친다.

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항공사진을 이용한 산지토사재해 영향인자 분석 - 강원도 평창군을 중심으로 - (Analysis of Influence Factors of Forest Soil Sediment Disaster Using Aerial Photographs - Case Study of Pyeongchang-county in Gangwon-province -)

  • 우충식;윤호중;이창우;정용호
    • 한국환경복원기술학회지
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    • 제11권1호
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    • pp.14-22
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    • 2008
  • The forest soil sediment disasters occurred in Jinbu-myeon Pyeongchang county were investigated characteristics by the aerial photograph analysis. After digitizing from aerial photographs, forest soil sediment disaster sites were classified into 695 collapsed sites, 305 flowed sites and 199 sediment sites. DEM (Digital Elevation Model) were generated from 1 : 5,000 digital topographic map. Factors of geography, hydrology, biology, and geology were analyzed using DEM, geologic map, and forest stand map with aerial photographs by GIS spatial analysis technique. The forest soil sediment disasters were mainly occurred from southeastern slope to southwestern slope. In collapsed sit es, the average slope degree is $28.9^{\circ}$, the average flow length is 163.5m, the average area of drainage basin is 897$m^2$. In case of flowed sites, the average slope degree, flow length, the area of drainage basin and confluence order is $27.0^{\circ}$, 175m, 2,500$m^2$ and 1, respectively. In sediment sites, the average slope, flow length, the area of drainage basin and confluence order is $12.5^{\circ}$, 2,50m, 25,000$m^2$ and 4, respectively. Also the forest soil sediment disasters were occurred most of collapsed sites in the afforest land after felling and igneous rocks composed of granite.

관통유동 해석 방법을 이용한 축류형 홴의 소음예측 (The Prediction of the Axial Flow Fan Noise by Using Through-Flow Analysis Method)

  • 이찬;정동규;홍순성
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 춘계학술대회논문집
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    • pp.371-379
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    • 2000
  • A noise prediction method of axial flow fan is developed by incorporating through-flow method and vortex shedding noise model. Fan noise is assumed to be generated due to the pressure fluctuation induced by wake vortices of fan blades and radiate as diploe distribution. The wake vortices are analyzed by combining Karman vortex street model and through-flow analysis results, and the vortex-induced fluctuating pressure on blade surface is calculated by thin airfoil theory. The predicted sound pressure levels and directivity patterns of fan noise by the present method are favorably compared with fan noise test data. Furthermore, the present method is shown to be very useful for predicting the aero-acoustic performance map of the fan operated at off-design point.

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Linear Eddy Model을 이용한 스칼라의 혼합특성 해석 (Analysis for Scalar Mixing Characteristics using Linear Eddy Model)

  • 김후중;김용모;안국영
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2004년도 제28회 KOSCO SYMPOSIUM 논문집
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    • pp.133-137
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    • 2004
  • The present study is focused on the small scale turbulent mixing processes in the scalar field. In order to deal with molecular mixing in turbulent flow, the linear eddy model is addressed. In each realization, the molecular mixing term is implemented deterministically, and turbulent stirring is represented by a sequence of instantaneous, statistically independent rearrangement event called by triplet map. The LEM approach is applied with relatively simple conditions. The characteristics of scalar mixing and PDF profiles are addressed in detail.

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