• 제목/요약/키워드: time-area method

검색결과 4,309건 처리시간 0.032초

강우 시간분포를 고려한 설계홍수량산정 (Estimation of Design Flood Considering Time Distribution of Rainfall)

  • 박재현;안상진;함창학;최민호
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2006년도 학술발표회 논문집
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    • pp.1191-1195
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    • 2006
  • Now days, heavy storm occur to be continue. It is hard to use before frequency based on flood discharge for decision that design water pocket structure. We need to estimation of frequency based on flood discharge on the important basin likely city or basin that damage caused by flood recurrence. In this paper flood discharge calculated by Clark watershed method and SCS synthetic unit hydrograph method about upside during each minute of among time distribution method of rainfall, Huff method choosing Bocheong Stream basin that is representative basin of International Hydrologic Project (IHP) about time distribution of rainfall that exert big effect at flood discharge estimate to research target basin because of and the result is as following. Relation between probability flood discharge that is calculated through frequency analysis about flood discharge data and rainfall - runoff that is calculated through outward flow model was assumed about $48.1{\sim}95.9%$ in the case of $55.8{\sim}104.0%$, SCS synthetic unit hydrograph method in case of Clark watershed method, and Clark watershed method has big value overly in case of than SCS synthetic unit hydrograph method in case of basin that see, but branch of except appeared little more similarly with frequency flood discharge that calculate using survey data. In the case of Critical duration, could know that change is big area of basin is decrescent. When decide time distribution type of rainfall, apply upside during most Huff 1-ST because heavy rain phenomenon of upsides appears by the most things during result 1-ST about observation recording of target area about Huff method to be method to use most in business, but maximum value of peak flood discharge appeared on Huff 3-RD too in the case of upside, SCS synthetic unit hydrograph method during Huff 3-RD incidental of this research and case of Clark watershed method. That is, in the case of Huff method, latitude is decide that it is decision method of reasonable design floods that calculate applying during all $1-ST{\sim}4-TH$.

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An Effective TOA-based Localization Method with Adaptive Bias Computation

  • Go, Seung-Ryeol
    • 전기전자학회논문지
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    • 제20권1호
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    • pp.1-8
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    • 2016
  • In this paper, we propose an effective time-of-arrival (TOA)-based localization method with adaptive bias computation in indoor environments. The goal of the localization is to estimate an accurate target's location in wireless localization system. However, in indoor environments, non-line-of-sight (NLOS) errors block the signal propagation between target device and base station. The NLOS errors have significant effects on ranging between two devices for wireless localization. In TOA-based localization, finding the target's location inside the overlapped area in the TOA-circles is difficult. We present an effective localization method using compensated distance with adaptive bias computation. The proposed method is possible for the target's location to estimate an accurate location in the overlapped area using the measured distances with subtracted adaptive bias. Through localization experiments in indoor environments, estimation error is reduced comparing to the conventional localization methods.

A Rule-based Urban Image Classification System for Time Series Landsat Data

  • Lee, Jin-A;Lee, Sung-Soon;Chi, Kwang-Hoon
    • 대한원격탐사학회지
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    • 제27권6호
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    • pp.637-651
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    • 2011
  • This study presents a rule-based urban image classification method for time series analysis of changes in the vicinity of Asan-si and Cheonan-si in Chungcheongnam-do, using Landsat satellite images (1991-2006). The area has been highly developed through the relocation of industrial facilities, land development, construction of a high-speed railroad, and an extension of the subway. To determine the yearly changing pattern of the urban area, eleven classes were made depending on the trend of development. An algorithm was generalized for the rules to be applied as an unsupervised classification, without the need of training area. The analysis results show that the urban zone of the research area has increased by about 1.53 times, and each correlation graph confirmed the distribution of the Built Up Index (BUI) values for each class. To evaluate the rule-based classification, coverage and accuracy were assessed. When Optimal allowable factor=0.36, the coverage of the rule was 98.4%, and for the test using ground data from 1991 to 2006, overall accuracy was 99.49%. It was confirmed that the method suggested to determine the maximum allowable factor correlates to the accuracy test results using ground data. Among the multiple images, available data was used as best as possible and classification accuracy could be improved since optimal classification to suit objectives was possible. The rule-based urban image classification method is expected to be applied to time series image analyses such as thematic mapping for urban development, urban development, and monitoring of environmental changes.

해양유류오염사고 위해도 평가에 관한 연구 (A Study on the Pollution Risk Assessment of Oil Spill Accidents)

  • 이문진;김혜진
    • 한국해양공학회지
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    • 제23권1호
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    • pp.24-30
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    • 2009
  • The purpose of this study was to establish an assessment method for the estimation of the pollution risk by oil spill accidents. Various oil spill patterns were calculated based on past accidents in the study area and these results were analyzed statistically. Then the risk probability, the oil arrival time, risk range, and so on were calculated. These calculations were performed for sub area sectors, fisheries and aquaculture farms, based on information about environmentally sensitive resources. Finally, the risk to each sub area sector was assessed by comparing the calculated results. These consequences indicated the objective and general risks of oil spill accidents and the result of this method will be made more appropriate by integrating real time risk predictions.

KALMAN FILTER기법을 이용한 실업자 수의 소지역 추정 (Small Area Estimation of Unemplyoment Using Kalman Filter Method)

  • 양영춘;이상은;신민웅
    • 응용통계연구
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    • 제16권2호
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    • pp.239-246
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    • 2003
  • 소지역에서 직접(direct) 시계열추정을 할 수 있다면, 소지역들 추정에서 최적선형 불편 예측량(BLUP)을 일반화 시킬 수 있다. 특히 조사에서 얻어지는 관측 값의 오차가 시간상으로 상관관계가 있다면 Kalman Filter(KF)기법이 사용 될 수 있다. 이 연구는 예측 값을 활용한 소지역의 실업자 수 추정에서 표본으로 추출되지 않은, 즉 관측되지 않은 값의 예측모형에 KF기법을 적용하였다. 이는 경제활동인구수를 이용하여 현 시점의 소지역 실업자 수를 예측함수(BLUP)를 통해 추정하게 된다. 그리고 이를 단순 회귀분석 추정치와 비교하였다.

움직임 벡터의 시공간적인 상관성을 이용한 예측 움직임 추정 기법 (Predictive motion estimation algorithm using spatio-temporal correlation of motion vector)

  • 김영춘;정원식;김중곤;이건일
    • 전자공학회논문지B
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    • 제33B권6호
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    • pp.64-72
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    • 1996
  • In this paper, we propose predictive motion estimatin algorithm which can predict motion without additional side information considering spatio-tempral correlatio of motion vector. This method performs motion prediction of current block using correlation of the motion vector for two spatially adjacent blocks and a temporally adjacent block. Form predicted motion, the position of searhc area is determined. Then in this searhc area, we estimate motion vector of current block using block matching algoirthm. Considering spatial an temporal correlation of motion vector, the proposed method can predict motion precisely much more. Especially when the motion of objects is rapid, this method can estimate motion more precisely without reducing block size or increasing search area. Futhrmore, the proposed method has computation time the same as conventional block matching algorithm. And as it predicts motion from adjacent blocks, it does not require additional side information for adjacent block. Computer simulation results show that motion estimation of proposed method is more precise than that of conventioanl method.

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출동현황자료 분석을 통한 재난대비 긴급차량 우선신호제어 시스템 도입지역 선정방안 연구 (A Selection Method of Implementation Area for Emergency Vehicle Preemption System Using Dispatch Data Analysis)

  • 성중기;하동익
    • 한국ITS학회 논문지
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    • 제15권2호
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    • pp.24-35
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    • 2016
  • 긴급차량 우선신호제어 시스템은 긴급차량의 출동여건을 개선할 수 있는 운영방안으로 아직까지 도입 기초단계이다. 따라서 국내 도입을 위해서는 단계적 계획과 이를 시행하기 위한 우선 도입지역 선정이 필요하다. 특히, 서울을 비롯한 광역지자체 단위의 사업 시행 시 모든 지역을 분석하기에는 시간과 비용 제약이 존재하며, 정량적이고 효율적인 도입지역 선정방안이 요구된다. 본 연구의 목적은 긴급차량 출동현황자료 분석을 통한 긴급차량 우선신호제어 시스템 도입지역 선정절차를 제시하는 것이다. 본 연구에서는 서울시 긴급차량 출동현황자료를 분석하여 우선 도입지역을 도출하였으며, 시뮬레이션 분석을 통해 도입에 따른 효과분석을 수행하였다.

숨겨진 오디오 비디오 시간 인덱스 신호를 사용한 DTV 립싱크 테스트 (DTV Lip-Sync Test Using Embedded Audio-Video Time Indexed Signals)

  • 한찬호;송규익
    • 대한전자공학회논문지SP
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    • 제41권3호
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    • pp.155-162
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    • 2004
  • 본 논문은 오디오 비디오 신호에 대한 유한한 DTV 디지털 스트림을 사용한 립싱크 테스트에 관한 것이다. 본 논문에서는 프로그램 시청이 가능하면서, 과도 효과 영역 테스트 신호(transient effect area test signals, TATS) 및 오디오 비디오 시간 인덱스 립싱크 테스트 신호를 이용한 새로운 립싱크 테스트 방법을 제안한다. 실험 결과에서 제안된 방법은 오실로스코프의 비디오 트리거 모드를 사용하여 오디오 및 비디오 신호간의 시간차를 쉽게 측정할 수 있음이 확인되었다.

구역 및 시간의존 차량스케쥴링문제 : 차량속도 추정모델과 차량스케쥴링 해법 (Area and Time-Dependent Vehicle Scheduling Problems Travel Speeds Estimation Model and Scheduling Heuristics)

  • 박양병;송성헌
    • 대한산업공학회지
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    • 제22권3호
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    • pp.517-532
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    • 1996
  • The area and time-dependent vehicle scheduling problem(ATVSP) is a generalization of the vehicle scheduling problem in which the travel speed between two locations depends on the passing areas and time of day. We propose a simple model for estimating area and time-dependent travel speeds in the ATVSP that relieves much burden for the data collection and storage problems. A mixed integer nonlinear programming formulation of the ATVSP is presented. We also propose three heuristics for the ATVSP, developed by extending and modifying existing heuristics for conventional vehicle scheduling problems. The results of computational experiments demonstrate that the proposed estimation model performs well and the saving method is the best among the three heuristics.

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백령도와 수도권의 황사 수송 시간과 바람장 분석 (Analysis of Asian Dust Transportation Time and Wind Farm in Baengnyeongdo Island and the Metropolitan Area)

  • 조원기;강동환;박경덕;양민준
    • 한국환경과학회지
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    • 제31권6호
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    • pp.525-533
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    • 2022
  • Baengnyeongdo, located within the Asian dust stream, is an ideal place to analyze Asian dust moving into the West Sea due to its low emission of artificial pollutants. Baengnyeongdo is being used to analyze the vertical distribution of dust from the lower atmosphere to the upper layer through remote observation. This study compared the ground concentration of dust between Baengnyeongdo and the metropolitan area, estimated the lag time of transport of Asian dust from Baengnyeongdo to the metropolitan area, and examined the homogeneity of upper winds using the rawinsonde method. The results showed that the cross correlation coefficient was higher and the lag time was shorter for each observation station when the distance from Baengnyeongdo was shorter. The upper wind at Baengnyeongdo is dominated by the west/northwest wind. It is the basis for the correlation of dust concentration between Baengnyeongdo and the metropolitan area located to the east. In the future, upper wind data and Asian dust concentration data over the West Sea and Baengnyeongdo are expected to contribute to research related to the movement and prediction of Asian dust and preparation for Asian dust in the metropolitan area.