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Forecasting Space Weather and Effects using Knowledge-Based Neurocomputing. H.Lundstedt, P.Wintoft, T.Hasanov, F. Boberg, H. Gleisner and I. Kronfeldt. Forecasting Space Weather and Effect using Knowledge-Based Neurocomputing - How did it all start in Lund?
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Forecasting Space Weather and Effects using Knowledge-Based Neurocomputing H.Lundstedt, P.Wintoft, T.Hasanov, F. Boberg, H. Gleisner and I. Kronfeldt
Forecasting Space Weather and Effect using Knowledge-Based Neurocomputing - How did it all start in Lund? - How has it been covered by media in Sweden? - What is Knowledge-Based Neurocomputing (KBN)? - ESA/Lund Forecast Service based on KBN
Work on Solar-Terrestrial Relations 1980-1981 Geomagnetic activity (Dst) after solar south- or northward directed B. Cosmic ray variation at time of solar wind IR and VAI (storminess)
Implementation of Lund Solar-Terrestrial Model, 1989 Inductive Expert System
Neural Network Prediction of Dst, Lund 1990 Space weather was mentioned for the first time in Swedish media 1991
Space weather and TV, 1997
Modeling and Forecasting with Knowledge-Based Neurocomputing The basis of using neural networks as mathematical models is ”mapping”. Given a dynamic system, a neural network can model it on the basis of a set of examples encoding the input/output behavior of the system. It can learn the mathematical function underlying the system operation (i.e. generalize not just fit a curve), if the network is designed (architechure, weights) and trained properly (learning algorithm). Both architechure and weights can be determined from differential equations which describe the causal relations between the physical variables (solution of diff eq is approximized by a RBF). The network (KBN) is then trained with observations. The architechure (number of input and hidden nodes) can also be determined from dynamic system analysis (reconstruction of the attractor from time series gives dimension). Neural networks can discover laws from regularities in data (Newton’s law e.g.). If one construct a hierachy of neural networks where networks at each level can learn knowledge at some level of abstraction, even more advanced laws can be dicovered.
Summary - Today’s forecast service is user oriented and in real-time - It will be implemented for specific users (power industry, satellite operators, public (RWC)) - The software package is developed in Java and therefore easily updated for new data and new better models - The stoplight events are logged to keep track of the quality of the forecasts