This work deals with process monitoring. In particular, the process of used-sand regeneration is monitored with the aid of impedance spectroscopy and can be controlled in the future with the measurement data obtained in this way. This results in the following aspects: a consistently high quality of the process material is realized by a controlled process. At the same time, energy consumption is minimized. The result is a process that is both more resource-efficient and more economical.

This paper deals with the electrical investigation of various sand mixtures used in foundries for mold and core production. It is possible to classify various molding sand mixtures reproducibly on the basis of their electrical characteristics. This knowledge can now be used to develop measurement systems for processes in the foundry industry and thus increase product quality. In addition, resources can be conserved, and functioning closed-loop systems can be integrated into foundry processes.

In this work we present a cost- and energy-efficient measurement system for the spatial detection of gas phases in liquid fluids with a low permittivity value. We showed that we can simulate the system and its environment and use the calculated results to interpret the results originating from measurements of the electrical capacitance between different electrodes. The proposed system can be modified for, e.g., observation of fluid behaviour in cryogenic tanks for reigniteable space propulsion.

A novel microwave-based approach for monitoring the state of aftertreatment systems such as diesel particulate filters (DPFs), three-way catalytic converters (TWCs), and selective catalytic reduction (SCR) catalysts is proposed. The interior of the catalyst metal housing serves as a communication channel between two wireless communication nodes. It is shown that, depending on the transmission channel characteristics, the properties of the catalyst, such as the catalyst state, can be inferred.

The current contribution reports on the substrate influence in multilayer metal-oxide chemical sensors. Measurements of the impedance are used to discuss the sensor performance with quartz substrates, (laboratory) glass substrates and substrates covered by silicon-dioxide insulating layers. Numerical experiments based on previous measurement results show that inexpensive glass substrates contribute up to 97% to the overall sensor responses.