Multivariate Alarm System Using Path Sampling and Machine Learning for Rare Abnormal Events

University of Pennsylvania

05/2019 - 08/2024
  • Using a novel combination of process modeling and molecular dynamics-based path-sampling algorithms, rare abnormal un-postulated unsafe/unreliable events were simulated efficiently, with a robust, predictive model developed using supervised machinelearning — this model was then utilized to develop novel, improved multivariate alarm systems

  • The multivariable alarm systems also includes automated/operator-assisted response actions that monitor the process in real-time to prevent abnormal 'crashing' to the undesirable operating region, supporting existing systems

  • Methods demonstrated initially on a simple exothermic CSTR led to promising multivariate alarm systems, with current focus on extending our analyses to a complex styrene polymerization CSTR with multiple potential undesirable operating regions

  • Tree-based ensemble machine learning algorithms (XGBoost, LightGBM) leveraged for developing highly accurate predictive models, capable of providing real-time tracking of the committer probabilities, resulting in improved, dynamic multivariate alarm systems

Alarm Rationalization and Dynamic Risk Assessment Rare Abnormal Events

University of Pennsylvania

05/2019 - 08/2024
  • Rationalization strategies introduced to evaluate the quality and effectiveness of the multivariate alarm systems, with appropriate modifications made based on key statistical metrics

  • Strategies resulted in a significant reduction in the number of nuisance alarms, focusing on only quality alarms, which, if ignored,were more likely to result in an abnormal shift in operation to the undesirable regions

  • Finally, the real-time risk of the rationalization systems were quantified using dynamic risk analysis and Bayesian Analyses, resulting in low-variance posterior distributions, updated easily online as more data are received