• 제목/요약/키워드: Prediction method

검색결과 9,019건 처리시간 0.036초

관개계획을 위한 기준작물 증발산량 산정 -고삼 저수지에 대한 사례연구- (Computation of Reference Crop Evapotranspiration for Irrigation Scheduling)

  • 정상옥
    • 한국농공학회지
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    • 제40권1호
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    • pp.43-48
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    • 1998
  • In order to provide basic information for the estimation of evapotranspiration for grass (Joycia Japonica), both field lysimeter experiment and model prediction were performed to estimate daily ET Various methods were used to predict daily reference crop ET and crop coefficients. Measured mean daily ET during the 1997 growing season was 4.5mm Model predicted mean daily ET during the 1997 growing season varied from 3.6 to 4.7mm depending on the prediction model Crop coefficients varied from 0.96 to 1.27 depending on the prediction model Comparison of the seven reference crop ET prediction methods used in this study shows that the Penman-Monteith method gave the smallest ET while the Hargreaves method gave the largest ET. The crop coefficient by the corrected Penman method was 1.03, which is closest to 1.0, suggesting that this method may he the best prediction method.

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차량 궤적 예측기법을 이용한 차량 정지/서행 순항 제어 (Vehicle Stop and Go Cruise Control using a Vehicle Trajectory Prediction Method)

  • 조상민;이경수
    • 한국자동차공학회논문집
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    • 제10권5호
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    • pp.206-213
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    • 2002
  • This paper proposes a vehicle trajectory prediction method for application to vehicle-to-vehicle distance control. This method is based on 2-dimensional kinematics and a Kalman filter has been used to estimate acceleration of the object vehicle. The simulation results using the proposed control method show that the relative distance characteristics can be improved via the trajectory prediction method compared to the customary vehicle stop and go cruise control systems which makes the vehicle remain at a safe distance from a preceding vehicle according to the driver's preference, automatically slow down and come to a full stop behind a preceding vehicle.

퍼지 클러스터링을 이용한 고농도오존예측 (Forecasting High-Level Ozone Concentration with Fuzzy Clustering)

  • 김재용;김성신;왕보현
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2001년도 춘계학술대회 학술발표 논문집
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    • pp.191-194
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    • 2001
  • The ozone forecasting systems have many problems because the mechanism of the ozone concentration is highly complex, nonlinear, and nonstationary. Also, the results of prediction are not a good performance so far, especially in the high-level ozone concentration. This paper describes the modeling method of the ozone prediction system using neuro-fuzzy approaches and fuzzy clustering. The dynamic polynomial neural network (DPNN) based upon a typical algorithm of GMDH (group method of data handling) is a useful method for data analysis, identification of nonlinear complex system, and prediction of a dynamical system.

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Complex Method를 이용한 자세예측 (Application of the Complex Method to Posture Prediction)

  • 박우진;최재호;정의승
    • 대한인간공학회:학술대회논문집
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    • 대한인간공학회 1996년도 춘계학술대회논문집
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    • pp.313-319
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    • 1996
  • Human posture prediction and motion simulaiton methods try to solve inverse kinematic problems based on the optimization concept. It is of great concern to develop an optimization method which soloves complicated optimization models in an efficient way in order for the models to be biomechanically sound. In this study, a new optimization method for posture prediction, which is named the Complex Method, is presented. The Complex Method demonstrates more flexibility in a way that it can deal with various forms of objective functions with constraints. This is because the method is a function-value-based approach. A two-eimensional whole-body lifting task was selected as an example of posture prediction, and a comparison study with te incrementation method was conducted in order to evaluate the accuracy of the Complex Method.

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추천 시스템을 위한 단계적 평가치 예측 방안 (A Stepwise Rating Prediction Method for Recommender Systems)

  • 이수정
    • 한국인터넷방송통신학회논문지
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    • 제21권4호
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    • pp.183-188
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    • 2021
  • 협력 필터링 기반의 추천 시스템은 현재 다양한 분야의 상업용 시스템의 필수불가결한 기능으로서, 사용자들이 선호할만한 상품을 맞춤형으로 제공해 주는 유용한 서비스이다. 그러나, 사용자들의 평가 데이타가 불충분할 경우 선호상품의 예측이 부정확할 우려가 크다. 본 연구에서는 이러한 단점을 해결하기 위하여 단계적으로 상품의 평가치를 예측하는 방안을 제시한다. 각 단계에 해당하는 예측 방법의 적용 조건을 만족하지 못할 경우 다음 단계의 방법을 적용한다. 제안 방법의 성능 평가를 위해, 공개 데이터셋을 활용한 실험을 진행하였으며, 제안 방법은 여러 전통적 유사도 척도를 도입한 협력 필터링 시스템의 예측 성능과 정밀도 성능을 크게 향상시켰고, 평가데이터 희소성 해결을 위한 기존 방식들의 성능을 능가하는 결과를 보였다.

An Application of GP-based Prediction Model to Sunspots

  • Yano, Hiroshi;Yoshihara, Ikuo;Numata, Makoto;Aoyama, Tomoo;Yasunaga, Moritoshi
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.523-523
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    • 2000
  • We have developed a method to build time series prediction models by Genetic Programming (GP). Our proposed CP includes two new techniques. One is the parameter optimization algorithm, and the other is the new mutation operator. In this paper, the sunspot prediction experiment by our proposed CP was performed. The sunspot prediction is good benchmark, because many researchers have predicted them with various kinds of models. We make three experiments. The first is to compare our proposed method with the conventional methods. The second is to investigate about the relation between a model-building period and prediction precision. In the first and the second experiments, the long-term data of annual sunspots are used. The third is to try the prediction using monthly sunspots. The annual sunspots are a mean of the monthly sunspots. The behaviors of the monthly sunspot cycles in tile annual sunspot data become invisible. In the long-term data of the monthly sunspots, the behavior appears and is complicated. We estimate that the monthly sunspot prediction is more difficult than the annual sunspot prediction. The usefulness of our method in time series prediction is verified by these experiments.

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코퍼스 방식 음성합성에서의 개선된 운율구 경계 예측 (AP, IP Prediction For Corpus-based Korean Text-To-Speech)

  • 권오일;홍문기;강선미;신지영
    • 음성과학
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    • 제9권3호
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    • pp.25-34
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    • 2002
  • One of the most important factor in the performance of Korean text-to-speech system is the prediction of accentual and intonational phrase boundary. The previous method of prediction shows only the 75-85% which is not proper in the practical and commercial system. Therefore, more accurate prediction must be needed in the practical system. In this study, we propose the simple and more accurate method of the prediction of AP, IP.

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유전자 알고리즘을 이용한 퍼지 시계열예측 방법에 관한 연구 (A Study on Fuzzy Time Series Prediction Method using the Genetic Algorithm)

  • 지현민;장우석;이성목;강환일
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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    • pp.622-624
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    • 2005
  • This paper proposes a time series prediction method for the nonllinear system using the fuzzy system and its genetic algorithm, At first, we obtain the optimal fuzzy membership function using the genetic algorithm. With the optimal fuzzy rules and its input differences, a better time prediction series system may be obtained. We obtain a good result for the time prediction of the electric load.

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차량 궤적 예측기법을 이용한 충돌 경보/회피 알고리듬 개발 (Development of Collision Warning/Avoidance Algorithms using Vehicle Trajectory Prediction Method)

  • 김재호;이경수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 추계학술대회논문집A
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    • pp.647-652
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    • 2000
  • This paper proposes a collision warning/avoidance algorithm using a trajectory prediction method. This algorithm is based on 2-dimensional kinematics and the Kalman filter has been used to obtain the information of the object vehicle. This algorithm has been investigated via computer simulation and showed a good trajectory prediction performance. The proposed collision warning/avoidance algorithm would enhanced driver acceptance for a collision warning/avoidance system.

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넙스(NURBS) 곡선 모델링을 이용한 발사체 음향하중 예측에 대한 연구 (A Study on Prediction of Acoustic Loads of Launch Vehicle Using NURBS Curve Modeling)

  • 박서룡;김홍일;이수갑
    • 한국항공우주학회지
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    • 제46권2호
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    • pp.106-113
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    • 2018
  • 발사체 발사 시 제트화염에 의해 발생하는 강력한 음향파는 음향하중의 형태로 비행체를 가진한다. 대표적인 경험적 음향하중 예측기법인 DSM-II(Distributed Source Method-II)는 제트화염 축을 따라 소음원을 배치하는 방법으로 계산비용 및 정확성 측면에서 장점을 갖는다. 하지만 소음원 배치 방법의 한계로 인해 다양한 발사대 환경을 정확하게 반영하기에는 한계가 있다. 본 연구에서는 넙스(Non-Uniform Rational B-Spline, NURBS) 곡선 모델링을 경험적 예측기법에 도입하여 자유롭게 소음원을 배치할 수 있는 음향하중 예측기법에 대한 연구를 수행하였다. 넙스 기법이 새롭게 도입된 해석기법의 검증을 위하여 Epsilon 로켓의 곡선형 저소음 발사대 형상에 대한 음향하중 예측을 수행하였고 해석 결과를 기존의 예측방법 및 실험 결과와 비교하였다.