Hochschule Aalen

Die Leistungsfähigkeit von Hörgeräten hinsichtlich ihrer Verstärkung und Wirksamkeit der Signalverarbeitungs[Ga1] -Features wird maßgeblich durch die Ankopplung an das Ohr bestimmt. Hier ist aus technischer Sicht eine möglichst geschlossene Ankopplung nötig, [zum vollständigen Text gelangen Sie über die oben angegebene URL]

This study constitutes the second part of a comprehensive investigation of the persistence of weighted average cost of capital (WACC) rates despite declining risk-free interest rates. While theory suggests that WACC should reflect lower risk-free interest rates and decline as well with falling government bond yields, empirical evidence reveals minimal adjustment in reported WACC figures. Disclosed WACC of DAX40 companies remain between 7% and 8% as yield of a ten-year German government bond fell from 4.1% to –0.2%. After the quantitative risk analysis (part I) systematically lacks market-based and fundamental explanations – demonstrating that neither systematic risk, overall market risk, earnings risk nor leverage increased sufficiently to justify this stability – this article addresses the resulting explanatory gap through qualitative inquiry. Employing grounded theory methodology, we investigate causes and consequences of persistent WACC through systematic analysis of 18 problem-centered semi-structured expert interviews (22 respondents comprising corporate finance executives, investment bankers, strategy consultants, auditors). The investigation reveals that behavioral economics (risk aversion, opportunism, subjectivity), organizational constraints (strategic path dependency, implementation complexity, financial criterion rigidity), and model-theoretic discretion (parameter averaging, analyst influence, supplementary risk adjustments) substantially shape practical WACC determination – factors that quantitative risk analysis cannot capture. Practitioners employ disclosed WACC strategically to reconcile investor return requirements with long-term operational stability, avoid audit friction, and hedge geopolitical-monetary risks – consequences that generate capital opportunity costs offsetting traditional value-maximization objectives. Combined quantitative and qualitative evidence yields actionable insights for value-based capital cost methodologies aligned with organizational and market realities.

A comprehensive understanding of aging phenomena in lithiumion batteries requires advanced analytical tools. This study applies a multi-method post-mortem approach to characterize structural and chemical changes in graphite anodes from cells cycled under conditions designed to induce lithium plating. The work is part of the SUSTAIN project, which supports the development of a catalog of battery damages to enable reliable diagnostics for second-life and recycling applications. Samples from aged and reference 18650-type cells were analyzed using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Raman spectroscopy, time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS), and laser-induced breakdown spectroscopy (LIBS). This combination enabled cross-validation of findings and a deeper insight into surface morphology, elemental composition, chemical bonding, and lithium distribution. The analysis revealed two distinct degradation features on the aged anodes—a porous carbon-rich surface and a localized mossy structure—each with unique signatures across the applied methods. The results highlight how different techniques complement each other in identifying electrolyte breakdown products, structural disorders, and lithium-related changes. This study demonstrates the value of a multi-method strategy for building a structured catalog of degradation modes, supporting condition diagnostics, and sustainable battery use.

Mass spectrometry (MS)-based top–down proteomics (TDP) has emerged as a powerful tool for characterizing proteoforms to advance both fundamental and translational research. TDP requires high-efficiency liquid-phase separation, high-resolution MS, and tandem MS. Capillary zone electrophoresis (CZE)-MS has been proposed as a promising analytical technique for protein analysis decades ago because of its unique and valuable features, including high separation efficiency and high detection sensitivity. However, CZE-MS has not been widely adopted by the proteomics community, mainly due to concerns with its robustness and reproducibility. Here, we hypothesized that CZE-MS is sufficiently robust and reproducible for broad adoption due to the continued efforts of the community over the last three decades. In this work, for the first time, research teams from around the world validated the robustness, repeatability, and reproducibility of CZE-MS for TDP in both simple and complex model proteoform mixtures employing a full spectrum of commercially available capillary electrophoresis (CE)-MS interfaces, instrumentation, and compared CZE-MS performance with state-of-the-art liquid chromatography (LC)-MS methods. This study offers the research community an informative resource of ready-to-use experimental CE-MS techniques and a better understanding of the CZE-MS approach and its potential in TDP, accelerating the broad adoption of CZE-MS in proteoform research.

Reactive multilayer foils (RMFs) offer highly localized heat generation through self-propagating exothermic reactions, making them attractive for advanced bonding applications. However, controlling the spatial and temporal distribution of heat remains a challenge. This study investigates the use of femtosecond laser micromachining to tailor the reaction dynamics of commercial Ni/Al reactive multilayer foils through the introduction of geometrical patterns. Four designs were chosen to impose distinct constraints on the reaction front. High-speed imaging combined with a custom image analysis algorithm enabled frame-by-frame tracking of local velocity fields. The results show that laser structuring can significantly alter reaction dynamics and propagation behavior by introducing front redirection, splitting and merging, leading to controlled delays and spatially localized acceleration zones. These effects enable modulation of global reaction times and localized energy release without suppressing or disrupting continuous front propagation. The findings demonstrate that laser structuring is an effective tool for tailoring heat delivery in RMF-based systems, with direct relevance to advanced bonding processes and thermally sensitive materials.

Soft X-ray tomography (SXT) enables native-contrast three-dimensional (3D) imaging of fully hydrated, cryogenically preserved biological samples, revealing ultrastructural details without the need for staining, embedding, or sectioning. Traditionally available only at synchrotron facilities, recent advances in laser-driven plasma sources have led to the development of compact soft X-ray microscopes. Achieving a resolution of 54nm full-pitch and tomogram acquisition times of 30min to two hours, we validate the system across a range of biologically relevant contexts, including protists, yeast, and mammalian cells containing polymeric and inorganic nanoparticles. These use cases establish the robustness of the laboratory based system for studying cell architecture, organelle interactions, and nanoparticle trafficking. By showing that a compact SXT system can achieve reliable high-resolution imaging across various cell types, this study highlights a major step toward making correlative cryogenic X-ray imaging broadly accessible in laboratory settings. Future developments will aim at enhanced throughput, deeper integration with correlative imaging modalities, and extension to more complex specimen types, including tissue.

Abstract Accurate prediction of the efficiency of electromechanical powertrains is crucial for the development of electric vehicles. Until now, this has been done through time-consuming and costly test bench investigations in late development phases. To address that, digital modeling and development processes are implemented in the product development process. Although, existing modeling approaches such as simulations or classical data-driven models often have limitations in terms of prediction accuracy, prediction speed, or model size. To address this problem, this paper develops five different data-driven modeling approaches for digital twins, ranging from simple black-box models to hybrid grey-box approaches. In addition, a sixth modeling approach, a white-box model, was conducted as a reference to the other model approaches. Validation is based on recorded measurement data from a test bench setup of an electromechanical powertrain consisting of a permanent magnet synchronous machine and a multi-stage transmission.The evaluation includes classic error metrics such as mean absolute error and mean relative error, but also model size, training times, and prediction speeds. In addition, a quotient of input and output variables is included, which is used to evaluate the information content of the model structure. Despite a slightly increased error tolerance, the final bright-grey-model approach offers the best compromise between prediction accuracy, real-time capability, and a high output-to-input quotient. The results demonstrate that data-driven digital twins with physically informed structures enable early and real-time prediction of the efficiency of electromechanical powertrains.

Pulsed near-infrared (NIR) lasers can be perceived as light of approximately half their wavelength due to the process of two-photon (2P) absorption. For high intensities of light, single-photon (1P) absorption can still be perceived beyond 700 nm, so that the overall color perception in this region is the result of a mix of 1P and 2P absorption. In this study, color matching experiments were performed with seven laser wavelengths between 730 and 920 nm to investigate the interaction between 1P and 2P absorption and the range of colors that can be created by changing the laser power and repetition frequency of a ns-pulsed laser. We recorded color matches in a range from pure red for shorter wavelengths across shades of purple up to pure blue colors for the longest wavelengths, showing that nonspectral (purple) colors can be created using only one stimulating wavelength in the NIR. Changes in hue could be observed between wavelengths of 850 nm and 920 nm when laser power or repetition frequency were modified, with the highest color shifts occurring between 880 nm and 900 nm.