Abstracted/indexed

A commercial solid electrolyte gas sensor of the type "Pt|YSZ|Pt, air" based on yttria-stabilized zirconia for colorimetric oxygen detection was operated in optimized dynamic electrochemical modes. Cyclic voltammetry and square-wave voltammetry were used for the detection of NO and O₂ in N₂ in the temperature range between 550 and 750 °C. Due to the differences of electrode kinetics of the single components it is possible to detect these redox active gases selectively and quasi-simultaneously.

This paper describes an optical sensor system based on the technique of laser speckle photometry (LSP) for the application of stress characterization and defect detection in ceramics. The purpose of the research is to develop an in-line inspection solution for the industrial field. The preliminary results show that the LSP technique has the potential to fulfill the task.

In this contribution, an inexpensive and robust impedimetric NO_x sensor is presented. The impedance of a functional thick film depends selectively on the NO_x concentration in the exhaust but shows a dependency on the oxygen concentration. Therefore, an additional temperature-independent resistive oxygen sensor structure was integrated on the same sensor platform. It serves not only to determine the oxygen concentration in the exhaust, but also to correct the oxygen dependency of the NO_x sensor.

In this paper, we present a tactile sensor based on the interaction of coils with a magnetic elastomer. The first experimental approach is sampling the sensor with indentations of constant depth at different positions. A mathematical model is used to reproduce the data. Afterwards, this model is applied to random indentations at the same depth. As a result, we provide conceptual proof for position determination in one direction as a basis for a refined sensor design and further model approaches.

A miniaturized, field-applicable sensor system was developed for the measurement of low hydrogen (H₂) concentrations in air. The sensor system is based on the application of a newly developed miniaturized coulometric detector with gas chromatographic (GC) pre-separation after injection. By optimizing all operational parameters, it was possible to conduct reproducible and 100 % selective H₂ measurements with more than 90 % analyte turnover compared to Faraday's law.

Deep learning has become a state-of-the-art method in machine learning, with a broad range of successful applications. Our goal is to explore the benefits of deep learning techniques for computational optical form measurements. The research is based on solving a nonlinear inverse problem aimed at the reconstruction of optical topographies from given processed interferograms. A U-Net network structure is chosen and tested on a simulated database. The obtained results are promising.

Symmetrical Pt | YSZ | Pt–NO gas sensors were produced with frit-containing and fritless Pt electrodes and fired between 950 and 1300 °C. The sensors were operated by pulsed polarization. With fritless pastes, the sensors responded significantly higher. The firing temperature affects the sensitivity only slightly. The low NO sensitivity of the frit-containing electrodes was attributed to a blocking effect at the triple-phase boundaries that inhibits the oxygen transport through the sensor.

We present a work on gas sensors that can for example be used for the assessment of indoor air quality. These sensors suffer from deterioration by siloxanes, so we investigated these effects by a distinct operation mode and exposition to this gas that allows us to interpret different reactions on the sensor surface. We found that all processes on the sensor surface are slowed down by this treatment and a self-compensation by the evaluation of oxygen adsorption processes is likely to be found.

The necessary reliability of wind turbine gearboxes increases the requirements for large gear measurements. However, standard measuring methods reach their limits for large gears with diameters > 1 m. Therefore a scalable optical gear measurement approach is presented. At first, simulation and experimental results prove the principle applicability of the measuring approach for small gear measurements. Geometric parameters of gears can be determined with a single-digit micrometer uncertainty.

In a very specific way, this research paper shows how established systems – in this case a commercial soot sensor for the automotive sector – can be optimized by diving deep into the basic research. The approach here is to link macroscopic observations or signal behavior with processes taking place on the atomic level. Taking these fundamental processes into account, the sensor's specific response time could be shortened effectively by a change in operating strategy – without any design changes.

In this paper we investigate an in-line concept for continuous monitoring of sodium, potassium, calcium and urea concentrations in blood serum using ion-selective electrodes. This concept is evaluated in a preclinical study with human packed red blood cells as a test medium. It has been shown that the electrolytes can be well monitored. In addition, we present the first measurements with ion-sensitive field-effect transistors in a miniaturized sensor assembly using a novel readout electronics.

This paper covers the design study of a multicomponent transducer (MCT) for wind turbine test benches. The MCT will cover the characteristics of wind turbines in the power range of up to 6 MW. The motivation to develop a MCT such as this is to provide satisfying measurement accuracy of loads and moments for all 6 degrees of freedom in order to reduce the uncertainty in the traceability of the drive train behavior due to the applied loads.

To improve the energy efficiency of industrial processes, such as continuous steel casting, lab-scale experiments with liquid metals are performed. We present an ultrasound Doppler signal process for multiplane, high-frame-rate flow imaging. We achieve real-time operations with an efficient implementation in a field-programmable gate array (FPGA). We analyze the contributions to the uncertainty of the velocity measurement and relate it to its fundamental limit.