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Engineering system design for automated space weather forecast : designing automatic software systems for the large-scale analysis of solar data, knowledge extraction and the prediction of solar activities using machine learning techniquesAlomari, Mohammad Hani January 2009 (has links)
Coronal Mass Ejections (CMEs) and solar flares are energetic events taking place at the Sun that can affect the space weather or the near-Earth environment by the release of vast quantities of electromagnetic radiation and charged particles. Solar active regions are the areas where most flares and CMEs originate. Studying the associations among sunspot groups, flares, filaments, and CMEs is helpful in understanding the possible cause and effect relationships between these events and features. Forecasting space weather in a timely manner is important for protecting technological systems and human life on earth and in space. The research presented in this thesis introduces novel, fully computerised, machine learning-based decision rules and models that can be used within a system design for automated space weather forecasting. The system design in this work consists of three stages: (1) designing computer tools to find the associations among sunspot groups, flares, filaments, and CMEs (2) applying machine learning algorithms to the associations' datasets and (3) studying the evolution patterns of sunspot groups using time-series methods. Machine learning algorithms are used to provide computerised learning rules and models that enable the system to provide automated prediction of CMEs, flares, and evolution patterns of sunspot groups. These numerical rules are extracted from the characteristics, associations, and time-series analysis of the available historical solar data. The training of machine learning algorithms is based on data sets created by investigating the associations among sunspots, filaments, flares, and CMEs. Evolution patterns of sunspot areas and McIntosh classifications are analysed using a statistical machine learning method, namely the Hidden Markov Model (HMM).
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Drag based forecast for CME arrivalJaklovsky, Simon January 2020 (has links)
Coronal Mass Ejections (CMEs) are considered to be one of the most energetic events in the heliosphere. Capable of inducing geomagnetic storms on Earth that can cause damage to electronics, a pillar which the modern society we live in leans heavily upon. Being able to accurately predict the arrival of CMEs would present us with the ability to issue timely warnings to authorities and commercial actors, allowing for protective measures to be put in place minimizing the damage. In this study the predicted arrival times and speeds from the Drag Based Model (DBM) and Drag Based Ensemble Model (DBEM) were compared to observational data from a set of 12 events containing fast, Earth-directed Halo CMEs and their corresponding shocks. Although DBM was developed to model CME propagation, varying some parameters allow it to be used for estimating shock/sheath arrival. The results presented in this study indicate that on average DBM performs best when the drag-parameter γ is in the range 0.2 ≤ γ ≤ 0.3. However the variability in the results show that determining a universal value of γ for fast CMEs does not increase the consistency in the model's performance. For completeness, further investigation is needed to account for not only halo CMEs. This will allow to test broader range of variation in the DBEM input parameters.
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Engineering System Design for Automated Space Weather Forecast. Designing Automatic Software Systems for the Large-Scale Analysis of Solar Data, Knowledge Extraction and the Prediction of Solar Activities Using Machine Learning Techniques.Alomari, Mohammad H. January 2009 (has links)
Coronal Mass Ejections (CMEs) and solar flares are energetic events taking
place at the Sun that can affect the space weather or the near-Earth environment by the
release of vast quantities of electromagnetic radiation and charged particles. Solar active
regions are the areas where most flares and CMEs originate. Studying the associations
among sunspot groups, flares, filaments, and CMEs is helpful in understanding the
possible cause and effect relationships between these events and features. Forecasting
space weather in a timely manner is important for protecting technological systems and
human life on earth and in space.
The research presented in this thesis introduces novel, fully computerised,
machine learning-based decision rules and models that can be used within a system
design for automated space weather forecasting. The system design in this work consists
of three stages: (1) designing computer tools to find the associations among sunspot
groups, flares, filaments, and CMEs (2) applying machine learning algorithms to the
associations¿ datasets and (3) studying the evolution patterns of sunspot groups using
time-series methods.
Machine learning algorithms are used to provide computerised learning rules
and models that enable the system to provide automated prediction of CMEs, flares, and
evolution patterns of sunspot groups. These numerical rules are extracted from the
characteristics, associations, and time-series analysis of the available historical solar
data. The training of machine learning algorithms is based on data sets created by
investigating the associations among sunspots, filaments, flares, and CMEs. Evolution
patterns of sunspot areas and McIntosh classifications are analysed using a statistical
machine learning method, namely the Hidden Markov Model (HMM).
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