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 Regional District of Okanagan-Similkameen


Probabilistic Solar Proxy Forecasting with Neural Network Ensembles

Daniell, Joshua D., Mehta, Piyush M.

arXiv.org Artificial Intelligence

Space weather indices are used commonly to drive forecasts of thermosphere density, which directly affects objects in low-Earth orbit (LEO) through atmospheric drag. One of the most commonly used space weather proxies, $F_{10.7 cm}$, correlates well with solar extreme ultra-violet (EUV) energy deposition into the thermosphere. Currently, the USAF contracts Space Environment Technologies (SET), which uses a linear algorithm to forecast $F_{10.7 cm}$. In this work, we introduce methods using neural network ensembles with multi-layer perceptrons (MLPs) and long-short term memory (LSTMs) to improve on the SET predictions. We make predictions only from historical $F_{10.7 cm}$ values, but also investigate data manipulation to improve forecasting. We investigate data manipulation methods (backwards averaging and lookback) as well as multi step and dynamic forecasting. This work shows an improvement over the baseline when using ensemble methods. The best models found in this work are ensemble approaches using multi step or a combination of multi step and dynamic predictions. Nearly all approaches offer an improvement, with the best models improving between 45 and 55\% on relative MSE. Other relative error metrics were shown to improve greatly when ensembles methods were used. We were also able to leverage the ensemble approach to provide a distribution of predicted values; allowing an investigation into forecast uncertainty. Our work found models that produced less biased predictions at elevated and high solar activity levels. Uncertainty was also investigated through the use of a calibration error score metric (CES), our best ensemble reached similar CES as other work.


An Application of Deep Learning for Sweet Cherry Phenotyping using YOLO Object Detection

Nagpal, Ritayu, Long, Sam, Jahagirdar, Shahid, Liu, Weiwei, Fazackerley, Scott, Lawrence, Ramon, Singh, Amritpal

arXiv.org Artificial Intelligence

Tree fruit breeding is a long-term activity involving repeated measurements of various fruit quality traits on a large number of samples. These traits are traditionally measured by manually counting the fruits, weighing to indirectly measure the fruit size, and fruit colour is classified subjectively into different color categories using visual comparison to colour charts. These processes are slow, expensive and subject to evaluators' bias and fatigue. Recent advancements in deep learning can help automate this process. Objective data can be generated for consistent characterization of germplasm, with greater speed and higher accuracy. A method was developed to automatically count the number of sweet cherry fruits in a camera's field of view in real time using YOLOv3. A system capable of analyzing the image data for other traits such as size and color was also developed using Python. The YOLO model obtained close to 99% accuracy in object detection and counting of cherries and 90% on the Intersection over Union metric for object localization when extracting size and colour information. The model surpasses human performance and offers a significant improvement compared to manual counting.


Death by GPS: are satnavs changing our brains?

The Guardian

One early morning in March 2011, Albert Chretien and his wife, Rita, loaded their Chevrolet Astro van and drove away from their home in Penticton, British Columbia. Their destination was Las Vegas, where Albert planned to attend a trade show. Rather than stick to the most direct route, they decided to take a scenic road less travelled, Idaho State Highway 51. The Chretiens figured there had to be a turnoff from Idaho 51 that would lead them east to US Route 93 all the way to Vegas. Albert and Rita had known each other since high school. During their 38 years of marriage, they had rarely been apart. They worked together, managing their own small excavation business.