Collaborative Research:Transfer Learning for Chemical Analyses from Laser-Induced Breakdown Spectroscopy

Mount Holyoke College, South Hadley MA

Investigators

Abstract

With support from the Chemical Measurements and Imaging program, Professors Melinda Dyar of Mt. Holyoke College and Sridhar Mahadevan of University of Massachusetts at Amherst and their students will use laser-induced breakdown spectroscopy (LIBS) measurements, including laboratory investigations of standard materials at varying experimental conditions, to develop numerical methods that will address limitations to the broad application of LIBS imposed by matrix effects and plasma variability. State-of-the-art dimensionality reduction and transfer learning methods from machine learning and statistics will be used to build innovative LIBS-based predictive models. These investigations will extend classical methods in statistics for dealing with multiple paired data sets, such as canonical correlational analysis, to deal with unlabeled data, and extract nonlinear low-dimensional regularities in the data. The project includes the design of a suite of model-building tools that can deal with a range of problems and optimization objectives, including different types of correspondence information available across datasets, diversity of global objectives ranging from preserving local to global geometry, and producing linear or nonlinear mappings to lower-dimensional factors. Laser-induced breakdown spectroscopy (LIBS) is a chemical analysis tool that uses the light emitted by a sample when a focused laser pulse generates a plasma at the sample surface. LIBS has a number of features that make it particularly useful for field use, including rapid analysis, minimal sample preparation and suitability for stand-off, that is remote, detection. Moreover, LIBS can detect and quantify light elements that are not always measured using other methods. Consequently, LIBS is well-suited to many applications including, defense interests (e.g., military explosive detection, illegal drug detection, airport security), in-situ analysis of archeological sites, field work at hazardous waste sites, and geological resource exploration. However, utilization of LIBS measurements is limited by signal variability with measurement and sample conditions. This project launches an integrated research program to couple state of the art LIBS instrumentation at Mount Holyoke College to equally state of the art numerical methodology in artificial intelligence and machine learning at the nearby University of Massachusetts to increase the utility of LIBS measurements. This project will provide an interdisciplinary training environment that includes undergraduate, graduate and post-doctoral researchers.