A PETSc parallel-in-time solver based on MGRIT algorithm

We address the development of a modular implementation of the MGRIT (MultiGrid-In-Time) algorithm to solve linear and nonlinear systems that arise from the discretization of evolutionary models with a parallel-in-time approach in the context of the PETSc (the Portable, Extensible Toolkit for Scientific computing) library. Our aim is to give the opportunity of predicting the performance gain achievable when using the MGRIT approach instead of the Time Stepping integrator (TS). To this end, we analyze the performance parameters of the algorithm that provide a-priori the best number of processing elements and grid levels to use to address the scaling of MGRIT, regarded as a parallel iterative algorithm proceeding along the time dimensio

Investigating the solder mask defects impact on leakage current on PCB under condensing humidity conditions

This paper focuses on conducting a thorough investigation into the solder mask defects and their influence on the leakage current development in PCB under operating conditions. A practical commercial PCBA has been used as a reference to construct a realistic numerical model, integrating the solder mask layer through COMSOL software. Comprehensive investigations cover scenarios with and without pinholes, conducting precise electrochemical reaction simulations under critical electrical conditions for validation against experimental data. The outcomes notably reveal how pinholes level up leakage current (LC) and reshape its paths. To validate the proposed method, experiments under real operating conditions and humidity were conducted. The comparison between the simulation and experiments demonstrated the effectiveness of the numerical model