Further development and optimisation of the CNN-classicification algorithm of Alfrödull for more accurate aerial image detection of decentralised solar energy systems: A study on how the performance of neural networks can beimproved through additional training data, image preprocessing, class balancing and sliding windowclassification
2024 (Engelska) Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hp
Studentuppsats (Examensarbete)
Abstract [en]
The global use of solar power is growing at an unprecedented rate, making the need toaccurately track the energy generation of decentralised solar energy systems (SES) more andmore relevant. The purpose of this thesis is to further develop a binary image classifier for thesimulation system framework known as Alfrödull, which will be used to detect and segment SESfrom aerial images to simulate the energy generation within a given Swedish municipality on anhourly basis. This project focuses on improving the Alfrödull classifier through four differentanalyses. the first focusing on examining how additional training data from publicly availabledatasets affects the model performance. The second on how the model can be improvedthrough the use of various image pre-processing techniques. The third on how the model canbe improved through balancing the training datasets to make up for the low amount of positiveimages as well as utilising model ensembles for joint classification. Finally, the fourth analysisemploys a sliding window approach to classify overlapping image tiles. The results show thathaving training data that is a good representation of the environment the model will be used in iscrucial, that the use of image augmentation policies can significantly improve modelperformance, that compensating for class imbalance as well as utilising ensemble methodspositively impacts model performance and that a sliding window approach to classifyingoverlapping images significantly decreases the amount of missed SES at the cost of clusters offalsely classified negative images (false positives). In conclusion, this thesis serves as animportant stepping stone in the practical implementation of the Alfrödull framework, showcasingthe key aspects in making a well performing binary image classifier of SES in Sweden.
Ort, förlag, år, upplaga, sidor 2024. , s. 31
Serie
UPTEC F, ISSN 1401-5757 ; 24010
Nyckelord [en]
AI, Machine learning, Classification model, Solar energy system, Binary classification, Neural networks, Convolutional neural network, Inception-v3, Solar energy system, Image analysis, Image pre-processing, Image augmentation, Sliding window algorithm, Training data
Nationell ämneskategori
Datorsystem
Identifikatorer URN: urn:nbn:se:uu:diva-533314 OAI: oai:DiVA.org:uu-533314 DiVA, id: diva2:1877286
Externt samarbete
Becquerel Sweden AB
Utbildningsprogram Civilingenjörsprogrammet i teknisk fysik
Presentation
2024-06-14, Over Zoom, -, Uppsala, 15:19 (Engelska)
Handledare
Examinatorer
2024-06-262024-06-252024-06-26 Bibliografiskt granskad