• Title/Summary/Keyword: seasonal forecast

검색결과 172건 처리시간 0.03초

건설경기동향조사와 건설기업경기실사지수의 비교연구 (A Comparison of Construction Cycle Trend Survey and Construction Business Survey Index)

  • 이동윤;강고운;이웅균;조훈희;강경인
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2015년도 추계 학술논문 발표대회
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    • pp.192-193
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    • 2015
  • Construction Cycle Trend Survey, which survey total value of orders and realized amounts monthly, is a valuable statistics that used to quick grasp or forecast the trend of domestic construction business. In recent periodical survey quality diagnoses, few professional users named a problem that Construction Cycle Trend Survey could not get together with the current state of the construction industry. This study examined weather Construction Cycle Trend Survey reflects the economic sentiment of construction business or not. Paired t test was performed between Construction Cycle Trend Survey and Construction Business Survey Index (CBSI), and significant differences were verified.

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여름강수량의 단기예측을 위한 Multi-Ensemble GCMs 기반 시공간적 Downscaling 기법 개발 (Development of Multi-Ensemble GCMs Based Spatio-Temporal Downscaling Scheme for Short-term Prediction)

  • 권현한;민영미
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2009년도 학술발표회 초록집
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    • pp.1142-1146
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    • 2009
  • A rainfall simulation and forecasting technique that can generate daily rainfall sequences conditional on multi-model ensemble GCMs is developed and applied to data in Korea for the major rainy season. The GCM forecasts are provided by APEC climate center. A Weather State Based Downscaling Model (WSDM) is used to map teleconnections from ocean-atmosphere data or key state variables from numerical integrations of Ocean-Atmosphere General Circulation Models to simulate daily sequences at multiple rain gauges. The method presented is general and is applied to the wet season which is JJA(June-July-August) data in Korea. The sequences of weather states identified by the EM algorithm are shown to correspond to dominant synoptic-scale features of rainfall generating mechanisms. Application of the methodology to seasonal rainfall forecasts using empirical teleconnections and GCM derived climate forecast are discussed.

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Application of Neural Networks For Estimating Evapotranspiration

  • Lee, Nam-Ho
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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    • pp.1273-1281
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    • 1993
  • Estimation of daily and seasonal evaportranspiration is essential for water resource planning irrigation feasibility study, and real-time irrigation water management . This paper is to evaluate the applicability of neural networks to the estimation of evapotranspiration . A neural network was developed to forecast daily evapotranspiration of the rice crop. It is a three-layer network with input, hidden , and output layers. Back-propagation algorithm with delta learning rule was used to train the neural network. Training neural network wasconducted usign daily actural evapotranspiration of rice crop and daily climatic data such as mean temperature, sunshine hours, solar radiation, relative humidity , and pan evaporation . During the training, neural network parameters were calibrated. The trained network was applied to a set of field data not used in the training . The created response of the neural network was in good agreement with desired values. Evaluating the neural networ performance indicates that neural network may be applied to the estimation of evapotranspiration of the rice crop.

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공공데이터를 이용한 맞춤형 영농 어플리케이션 설계 및 구현 (Design and Implementation of Customized Farming Applications using Public Data)

  • 고주영;윤성욱;김현기
    • 한국멀티미디어학회논문지
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    • 제18권6호
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    • pp.772-779
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    • 2015
  • Advancing information technology have rapidly changed our service environment of life, culture, and industry. Computer information communication system is applied in medical, health, distribution, and business transaction. Smart is using new information by combining ability of computer and information. Although agriculture is labor intensive industry that requires a lot of hands, agriculture is becoming knowledge-based industry today. In agriculture field, computer communication system is applied on facilities farming and machinery Agricultural. In this paper, we designed and implemented application that provides personalized agriculture related information at the actual farming field. Also, this provides farmer a system that they can directly auction or sell their produced crops. We designed and implemented a system that parsing information of each seasonal, weather condition, market price, region based, crop, and disease and insects through individual setup on ubiquitous environment using location-based sensor network and processing data.

ARIMA 모형과 인공신경망모형의 BOD예측력 비교 (Comparison of the BOD Forecasting Ability of the ARIMA model and the Artificial Neural Network Model)

  • 정효준;이홍근
    • 한국환경보건학회지
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    • 제28권3호
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    • pp.19-25
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    • 2002
  • In this paper, the water quality forecast was performed on the BOD of the Chungju Dam using the ARIMA model, which is a nonlinear statistics model, and the artificial neural network model. The monthly data of water quality were collected from 1991 to 2000. The most appropriate ARIMA model for Chungju dam was found to be the multiplicative seasonal ARIMA(1,0,1)(1,0,1)$_{12}$, model. While the artificial neural network model, which is used relatively often in recent days, forecasts new data by the strength of a learned matrix like human neurons. The BOD values were forecasted using the back-propagation algorithm of multi-layer perceptrons in this paper. Artificial neural network model was com- posed of two hidden layers and the node number of each hidden layer was designed fifteen. It was demonstrated that the ARIMA model was more appropriate in terms of changes around the overall average, but the artificial neural net-work model was more appropriate in terms of reflecting the minimum and the maximum values.s.

시간별 전력부하 예측 (Hourly load forecasting)

  • 김문덕;이윤섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1992년도 하계학술대회 논문집 A
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    • pp.495-497
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    • 1992
  • Hourly load forecasting has become indispensable for practical simulation of electric power system as the system become larger and more complicated. To forecast the future hourly load the cyclic behavior of electric load which follows seasonal weather, day or week and office hours is to be analyzed so that the trend of the recent behavioral change can be extrapolated for the short term. For the long term, on the other hand, the changes in the infra-structure of each electricity consumer groups should be assessed. In this paper the concept and process of hourly load forecasting for hourly load is introduced.

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A Distributed Medium Access Control Protocol for Cognitive Radio Ad Hoc Networks

  • Joshi, Gyanendra Prasad;Kim, Sung Won;Kim, Changsu;Nam, Seung Yeob
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권1호
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    • pp.331-343
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    • 2015
  • We propose a distributed medium access control protocol for cognitive radio networks to opportunistically utilize multiple channels. Under the proposed protocol, cognitive radio nodes forecast and rank channel availability observing primary users' activities on the channels for a period of time by time series analyzing using smoothing models for seasonal data by Winters' method. The proposed approach protects primary users, mitigates channel access delay, and increases network performance. We analyze the optimal time to sense channels to avoid conflict with the primary users. We simulate and compare the proposed protocol with the existing protocol. The results show that the proposed approach utilizes channels more efficiently.

전력소비자의 단기수요예측을 위한 전력소비패턴과 환경요인과의 관계 분석 (Relationship Analysis of Power Consumption Pattern and Environmental Factor for a Consumer's Short-term Demand Forecast)

  • 고종민;송재주;김영일;양일권
    • 전기학회논문지
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    • 제59권11호
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    • pp.1956-1963
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    • 2010
  • Studies on the development of various energy management programs and real-time bidirectional information infrastructures have been actively conducted to promote the reduction of power demands and CO2 emissions effectively. In the conventional energy management programs, the demand response program that can transition or transfer the power use spontaneously for power prices and other signals has been largely used throughout the inside and outside of the country. For measuring the effect of such demand response program, it is necessary to exactly estimate short-term loads. In this study, the power consumption patterns in both individual and group consumers were analyzed to estimate the exact short-term loads, and the relationship between the actual power consumption and seasonal factors was also analyzed.

IoT 환경에서 예측 정확도 향상을 위한 계절성 비선형 시계열 알고리즘 설계 (Design of Seasonal Nonlinear Time Series Algorithm for Improving Forecast Accuracy in IoT Environment)

  • 강정구;박석천;김종현
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2015년도 춘계학술발표대회
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    • pp.645-648
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    • 2015
  • ICT 시대를 맞아 하루가 다르게 새로운 기술이 등장하고 있으며, 최근에는 사물인터넷 시대까지 도래하였다. 하지만 현재 사물인터넷에서 폭발적으로 발생되는 시계열 데이터를 분석하는 연구는 미비한 상태이다. 따라서 본 논문에서는 사물인터넷에서 발생되는 시계열 데이터의 예측 정확도 향상을 위해 사계절이 뚜렷한 우리나라의 계절성 특성을 고려한 SARIMA알고리즘과 비선형 특성 예측 알고리즘인 SVM을 결합한 하이브리드 SARIMA-SVM알고리즘을 제안 한다.

SVM을 이용한 계절별 호우 상황 예측 기법 (Seasonal Heavy Rain Forecast Using SVMs)

  • 이재동;이성우;김재광;이지형
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2012년도 춘계학술발표대회
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    • pp.324-326
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    • 2012
  • 본 연구에서는 날씨를 나타내는 속성들의 값을 이용하여 현재로부터 6시간 후의 호우/비호우를 예측하기 위한 기법을 연구한다. 본 연구를 통해 호우/비호우 예측을 할 때 각 속성 값들이 호우, 비호우를 나타내는 일기도의 특정 패턴에 영향을 받는지 혹은 계절별로 영향을 받는지를 살펴보았다. 실험을 위하여 20년 누적 일기도를 SVM으로 학습하고 호우와 비호우 각각의 정답 집합을 이용하여 테스트 하였다. 실험 결과 SVM의 호우 예측도는 최대 70% 정도의 정확률을 보였으며 예측에 영향을 주는 것은 특정 패턴보다는 계절에 따른 변화임을 알아내었다.