archival data
Beamline Steering Using Deep Learning Models
Allen, Dexter, Kante, Isaac, Bohler, Dorian
Beam steering involves the calibration of the angle and position at which a particle accelerator's electron beam is incident upon the x-ray target with respect to the rotation axis of the collimator. Beam Steering is an essential task for light sources. The Linac To Undulator is very difficult to steer and aim due to the changes of each use of the accelerator there must be re-calibration of magnets. However with each use of the Beamline its current method of steering runs into issues when faced with calibrating angles and positions. Human operators spend a substantial amount of time and resources on the task. We developed multiple different feed-forward-neural networks with varying hyper-parameters, inputs, and outputs, seeking to compare their performance. Specifically, our smaller models with 33 inputs and 13 outputs outperformed the larger models with 73 inputs and 50 outputs. We propose the following explanations for this lack of performance in larger models. First, a lack of training time and computational power limited the ability of our models to mature. Given more time, our models would outperform SVD. Second, when the input size of the model increases the noise increases as well. In this case more inputs corresponded to a greater length upon the LINAC accelerator. Less specific and larger models that seek to make more predictions will inherently perform worse than SVD.
Optimal Transport for Fairness: Archival Data Repair using Small Research Data Sets
Langbridge, Abigail, Quinn, Anthony, Shorten, Robert
With the advent of the AI Act and other regulations, there is now an urgent need for algorithms that repair unfairness in training data. In this paper, we define fairness in terms of conditional independence between protected attributes ($S$) and features ($X$), given unprotected attributes ($U$). We address the important setting in which torrents of archival data need to be repaired, using only a small proportion of these data, which are $S|U$-labelled (the research data). We use the latter to design optimal transport (OT)-based repair plans on interpolated supports. This allows {\em off-sample}, labelled, archival data to be repaired, subject to stationarity assumptions. It also significantly reduces the size of the supports of the OT plans, with correspondingly large savings in the cost of their design and of their {\em sequential\/} application to the off-sample data. We provide detailed experimental results with simulated and benchmark real data (the Adult data set). Our performance figures demonstrate effective repair -- in the sense of quenching conditional dependence -- of large quantities of off-sample, labelled (archival) data.
AI learns physics to optimize particle accelerator performance
Machine learning, a form of artificial intelligence, vastly speeds up computational tasks and enables new technology in areas as broad as speech and image recognition, self-driving cars, stock market trading and medical diagnosis. Before going to work on a given task, machine learning algorithms typically need to be trained on pre-existing data so they can learn to make fast and accurate predictions about future scenarios on their own. But what if the job is a completely new one, with no data available for training? Now, researchers at the Department of Energy's SLAC National Accelerator Laboratory have demonstrated that they can use machine learning to optimize the performance of particle accelerators by teaching the algorithms the basic physics principles behind accelerator operations--no prior data needed. "Injecting physics into machine learning is a really hot topic in many research areas--in materials science, environmental science, battery research, particle physics and more," said Adi Hanuka, a former SLAC research associate who led a study published in Physical Review Accelerator and Beams.
Mysterious radio signals from billions of light-years away can now be detected in real time
A PhD student in Australia has developed an automated system to detect, in real time, mysterious radio pulses emanating from the deep universe. The fleeting signals known as fast radio bursts (FRBs) have baffled scientists since they were first discovered in 2007 by a team poring through archival data. Since then, there have been numerous other instances of their detection – though what exactly causes them remains a mystery. The latest breakthrough could be a huge leap forward for scientists' ability to understand the nature of fast radio bursts, allowing them to be captured in detail the moment they reach Earth. A PhD student in Australia has developed an automated system to detect, in real-time, mysterious radio pulses emanating from the deep universe.