TY - JOUR
AB - The production of hydrogen and the utilization of biomass for sustainable concepts of energy conversion and storage require gas sensors that discriminate between hydrogen (H2) and carbon monoxide (CO). Mesoporous copper–ceria (Cu–CeO2) materials with large specific surface areas and uniform porosity are prepared by nanocasting, and their textural properties are characterized by N2 physisorption, powder XRD, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. The oxidation states of copper (Cu+, Cu2+) and cerium (Ce3+, Ce4+) are investigated by XPS. The materials are used as resistive gas sensors for H2 and CO. The sensors show a stronger response to CO than to H2 and low cross-sensitivity to humidity. Copper turns out to be a necessary component; copper-free ceria materials prepared by the same method show only poor sensing performance. By measuring both gases (CO and H2) simultaneously, it is shown that this behavior can be utilized for selective sensing of CO in the presence of H2.
AU - Baier, Dominik
AU - Priamushko, Tatiana
AU - Weinberger, Christian
AU - Kleitz, Freddy
AU - Tiemann, Michael
ID - 43457
IS - 4
JF - ACS Sensors
KW - Fluid Flow and Transfer Processes
KW - Process Chemistry and Technology
KW - Instrumentation
KW - Bioengineering
SN - 2379-3694
TI - Selective Discrimination between CO and H2 with Copper–Ceria-Resistive Gas Sensors
VL - 8
ER -
TY - CONF
AB - Abstract. The combination of incremental sheet metal forming and high-speed forming offers new possibilities for flexible forming processes in the production of large sheet metal components of increased complexity with relatively low forming energies. In this paper, the general feasibility and process differences between the pulse-driven high-speed forming technologies of electrohydraulic and electromagnetic forming were investigated. An example component made of EN AW 6016 aluminum sheet metal was thus formed incrementally by both processes and the forming result evaluated by an optical 3D measurement system. For this purpose, a forming strategy for electromagnetic incremental forming (EMIF) was developed, tested and adapted to the electrohydraulic incremental forming process (EHIF). The discharge energy, the tool displacement and the pressure field of the forming zone were determined as relevant parameters for the definition of an adequate tool path strategy. It was found that the EHIF process is less affected by larger distances between the tool and the blank, while this is a critical variable for force application to the component during EMIF. On the other hand, the more uniform pressure distribution of the EMIF process is advantageous for forming large steady component areas.
AU - Holzmüller, Maik
AU - Linnemann, Maik
AU - Homberg, Werner
AU - Psyk, Verena
AU - Kräusel, Verena
AU - Kroos, Janika
ID - 43044
KW - Incremental Sheet Forming
KW - Aluminium
KW - High-Speed Forming
SN - 2474-395X
T2 - Materials Research Proceedings
TI - Proof of concept for incremental sheet metal forming by means of electromagnetic and electrohydraulic high-speed forming
VL - 25
ER -
TY - JOUR
AB - The pressure fields generated by two simultaneous discharges have not been investigated on any notable scale for the electrohydraulic impulse forming method. In this study, the synchronicity of two discharges is ensured by the sequential connection of two wires mounted in two spark gaps in a common volume of liquid. The objective is to experimentally confirm the equilibrium of the energies evolved in two spark gaps by means of pressure measurements. In addition, multipoint membrane pressure gauges demonstrated the feasibility of easily recording detailed pressure maps. Based on the membrane deformation mechanism and material strengthening under static and impulse conditions, the processing procedure is further developed so as to achieve better accuracy in the determination of pressure field parameters. The practical equality of the pressure fields on the left and right halves of the flat-loaded area confirms the equality of energies evolved in the two spark gaps. The direct shock waves create zones with the most intensive loading. These results provide a basis for the development of new electrohydraulic technologies involving the application of two simultaneous discharges with equal energy and pressure parameters.
AU - Knyazyev, Mykhaylo
AU - Holzmüller, Maik
AU - Homberg, Werner
ID - 43045
IS - 1
JF - Journal of Manufacturing and Materials Processing
KW - impulse
KW - forming
KW - electrohydraulic
KW - discharge
KW - wire
KW - pressure gauge
KW - pressure field
SN - 2504-4494
TI - Investigation of Pressure Fields Generated by Two Simultaneous Discharges in Liquid Initiated by Wires
VL - 7
ER -
TY - JOUR
AU - Neumann, Phillip
ID - 44321
IS - 5
JF - Zeitschrift für Heilpädagogik
KW - Inklusion
KW - Sonderpädagogik
KW - Bildung
KW - Bildungsstudien
KW - Integration
SN - 0513-9066
TI - Studien zu Schulleistungen und ihre Aufbereitung
VL - 74
ER -
TY - CONF
AU - Hami Dindar, Iman
AU - Lutters, Nicole
AU - Kenig, Eugeny
ID - 44320
T2 - Jahrestreffen der ProcessNet-Fachgruppen Fluidverfahrenstechnik und Adsoprtion
TI - Wässrige Glucosaminlösung als neues Lösungsmittel zur CO2-Abscheidung
ER -
TY - CONF
AB - State estimation when only a partial model of a considered system is available remains a major challenge in many engineering fields. This work proposes a joint, square-root unscented Kalman filter to estimate states and model uncertainties simultaneously by linear combinations of physics-motivated library functions. Using a sparsity promoting approach, a selection of those linear combinations is chosen and thus an interpretable model can be extracted. Results indicate a small estimation error compared to a traditional square-root unscented Kalman filter and exhibit the enhancement of physically meaningful models.
AU - Götte, Ricarda-Samantha
AU - Timmermann, Julia
ID - 34171
IS - 1
KW - joint estimation
KW - unscented transform
KW - Kalman filter
KW - sparsity
KW - data-driven
KW - compressed sensing
T2 - 12th IFAC Symposium on Nonlinear Control Systems (NOLCOS 2022)
TI - Estimating States and Model Uncertainties Jointly by a Sparsity Promoting UKF
VL - 56
ER -
TY - JOUR
AB - Room temperature sodium-sulfur (RT Na-S) batteries are considered potential candidates for stationary power storage applications due to their low cost, broad active material availability and low toxicity. Challenges, such as high volume expansion of the S-cathode upon discharge, low electronic conductivity of S as active material and herewith limited rate capability as well as the shuttling of polysulfides (PSs) as intermediates often impede the cycle stability and practical application of Na-S batteries. Sulfurized poly(acrylonitrile) (SPAN) inherently inhibits the shuttling of PSs and shows compatibility with carbonate-based electrolytes, however, its exact redox mechanism remained unclear to date. Herein, we implement a commercially available and simple electrolyte into the Na-SPAN cell chemistry and demonstrate its high rate and cycle stability. Through the application of in situ techniques utilizing electronic impedance spectroscopy (EIS) and X-ray absorption spectroscopy (XAS) at different depths of charge and discharge, an insight into SPAN’s redox chemistry is obtained.
AU - Kappler, Julian
AU - Tonbul, Güldeniz
AU - Schoch, Roland
AU - Murugan, Saravanakumar
AU - Nowakowski, Michał
AU - Lange, Pia Lena
AU - Klostermann, Sina Vanessa
AU - Bauer, Matthias
AU - Schleid, Thomas
AU - Kästner, Johannes
AU - Buchmeiser, Michael Rudolf
ID - 40981
IS - 1
JF - Journal of The Electrochemical Society
KW - Materials Chemistry
KW - Electrochemistry
KW - Surfaces
KW - Coatings and Films
KW - Condensed Matter Physics
KW - Renewable Energy
KW - Sustainability and the Environment
KW - Electronic
KW - Optical and Magnetic Materials
SN - 0013-4651
TI - Understanding the Redox Mechanism of Sulfurized Poly(acrylonitrile) as Highly Rate and Cycle Stable Cathode Material for Sodium-Sulfur Batteries
VL - 170
ER -
TY - JOUR
AB - The success of engineering complex technical systems is determined by meeting customer requirements and institutional regulations. One example relevant to the automobile industry is the United Nations Economic Commission of Europe (UN ECE), which specifies the homologation of automobile series and requires proof of traceability. The required traceability can be achieved by modeling system artifacts and their relations in a consistent, seamless model—an effect-chain model. Currently, no in-depth methodology exists to support engineers in developing certification-compliant effect-chain models. For this purpose, a new methodology for certification-compliant effect-chain modeling was developed, which includes extensions of an existing method, suitable models, and tools to support engineers in the modeling process. For evaluation purposes, applicability is proven based on the experience of more than 300 workshops at an automotive OEM and an automotive supplier. The following case example is chosen to demonstrate applicability: the development of a window lifter that has to meet the demands of UN ECE Regulations R156 and R21. Results indicate multiple benefits in supporting engineers with the certification-compliant modeling of effect chains. Three benefits are goal-oriented modeling to reduce the necessary modeling capacity, increasing model quality by applying information quality criteria, and the potential to reduce costs through automatable effect-chain analyses for technical changes. Further, companies in the automotive and other industries will benefit from increased modeling capabilities that can be used for architecture modeling and to comply with other regulations such as ASPICE or ISO 26262.
AU - Gräßler, Iris
AU - Wiechel, Dominik
AU - Koch, Anna-Sophie
AU - Sturm, Tim
AU - Markfelder, Thomas
ID - 44382
IS - 3
JF - Systems
KW - Information Systems and Management
KW - Computer Networks and Communications
KW - Modeling and Simulation
KW - Control and Systems Engineering
KW - Software
SN - 2079-8954
TI - Methodology for Certification-Compliant Effect-Chain Modeling
VL - 11
ER -
TY - GEN
AU - Tonbul, Güldeniz
AU - Kappler, Julian
AU - Murugan, Saravanakumar
AU - Schoch, Roland
AU - Nowakowski, Michal
AU - Lange, Pia
AU - Bauer, Matthias
AU - Buchmeiser, Michael R.
ID - 44380
TI - Characterization of Na-S Battery System Using X-ray Absorption Spectroscopy
ER -
TY - CONF
AB - The development of autonomous vehicles and their introduction in urban traffic offer many opportunities for traffic improvements. In this paper, an approach for a future traffic control system for mixed autonomy traffic environments is presented. Furthermore, a simulation framework based on the city of Paderborn is introduced to enable the development and examination of such a system. This encompasses multiple elements including the road network itself, traffic lights, sensors as well as methods to analyse the topology of the network. Furthermore, a procedure for traffic demand generation and routing is presented based on statistical data of the city and traffic data obtained by measurements. The resulting model can receive and apply the generated control inputs and in turn generates simulated sensor data for the control system based on the current system state.
AU - Link, Christopher
AU - Malena, Kevin
AU - Gausemeier, Sandra
AU - Trächtler, Ansgar
ID - 44390
KW - Traffic Simulation
KW - Traffic Control
KW - Car2X
KW - Mixed Autonomy
KW - Autonomous Vehicles
KW - SUMO
KW - Sensor Simulation
KW - Traffic Demand Generation
KW - Routing
KW - Traffic Lights
KW - Graph Analysis
KW - Traffic Observer
SN - 978-989-758-652-1
T2 - Proceedings of the 9th International Conference on Vehicle Technology and Intelligent Transport Systems
TI - Simulation Environment for Traffic Control Systems Targeting Mixed Autonomy Traffic Scenarios
ER -