Process Mining of Programmable Logic Controllers: Input/Output Event Logs

This paper presents an approach to model an unknown Ladder Logic based Programmable Logic Controller (PLC) program consisting of Boolean logic and counters using Process Mining techniques. First, we tap the inputs and outputs of a PLC to create a data flow log. Second, we propose a method to translate the obtained data flow log to an event log suitable for Process Mining. In a third step, we propose a hybrid Petri net (PN) and neural network approach to approximate the logic of the actual underlying PLC program. We demonstrate the applicability of our proposed approach on a case study with three simulated scenarios

A computational model for switch surfaces

Advisors: Behrooz Fallahi.Committee members: Brian D. Coller; Ji-Chul Ryu.Computation of contact points between the wheel and rail is a fundamental problem in dynamic simulation of trains. For this purpose, an accurate model of a switch surface is needed. The objective of this study is to develop a mathematical model for a switch. The model for the switch will be based on skin surface scheme whereby a number of profiles will be place along a track curve. Each profile will be divided into segments of similar shapes. Then, each set will be used in an interpolation scheme to generate the switch surface.M.S. (Master of Science