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Aging matrix visualizes complexity of battery aging across hundreds of cycling protocols
No full textTo reliably deploy lithium-ion batteries, a fundamental understanding of cycling aging behavior is critical. Battery aging consists of complex and highly coupled phenomena, making it challenging to develop a holistic interpretation. In this work, we generate a diverse battery cycling dataset with a broad range of degradation trajectories, consisting of 359 high energy density commercial Li(Ni,Co,Al)O₂/graphite + SiOₓ cylindrical 21 700 cells cycled across 207 unique cycling protocols. We consolidate aging via 16 mechanistic state-of-health (SOH) metrics, including cell-level performance metrics, electrode-specific capacities/state-of-charges (SOCs), and aging trajectory metrics. We develop a framework using interpretable machine learning and explainable features to generate an aging matrix that visually deconvolutes the complex battery degradation behavior. This generalizable data-driven mechanistic framework simplifies the complex interplay between cycling conditions, degradation modes, and SOH, acting as a hypothesis-generation tool to aid battery users in identifying key degradation regimes for further study and experimentation
Vor 50 Jahren… Walter Humbach - erster Professor für Reaktortechnik
No full textAls Walter Humbach im Jahr 1962 den Lehrstuhl für Reaktortechnik übernahm, stand das Institut noch ganz am Anfang. Die Bundesrepublik hatte erst 1955 von den Alliierten die Souveränität erhalten. Dies erlaubte unter anderem die Forschung zur friedlichen Nutzung der Kernenergie
Rethinking Knowledge Brokerage: A Case Study of a Large Language Model in R&D
No full textThe work of knowledge brokers comprises the transfer, translation, and transformation of knowledge between individuals who are unlikely to interact efficiently because of knowledge boundaries. In an extension of this theory, algorithmic brokers are defined as individuals performing these practices with artificial intelligence (AI) output to enable a community to leverage this output in their work. However, with the introduction of large language models (LLMs), we argue this brokerage role is shifting and that LLMs have the potential to broker knowledge between humans. We conducted a case study with domain experts in a Research and Development (R&D) department of a large multinational science and technology company who regularly use a recently developed domain-specific R&D-LLM. Our preliminary findings show that the R&D-LLM is reshaping interactions between human experts through three knowledge brokerage practices of varying complexity, assisting in simple knowledge recall, enabling the approach to experts and being a simulated counterpart
Using Information-Seeking Argument Mining to Improve Service
No full textIf service providers can identify reasons users are in favor of or against a service, they have insightful information that can help them understand user behavior and what they need to do to change such behavior. This article argues that the novel text-mining technique referred to as information-seeking argument mining (IS-AM) can identify these reasons. The empirical study applies IS-AM to news articles and reviews about electric scooter-sharing systems (i.e., a service enabling the short-term rentals of electric motorized scooters). Its results point to IS-AM as a promising technique to improve service; the data enable the authors to identify 40 reasons to use or not use electric scooter-sharing systems, as well as their importance to users. Furthermore, the results show that news articles are better data sources than reviews because they are longer and contain more arguments and, thus, reasons
Liberale Demokratietheorie in der Krise
No full textSchaut man auf den politikwissenschaftlichen Büchermarkt der letzten Jahre, so fällt eine deutliche Zunahme von Titeln ins Auge, die eine „Regression“, eine „Krise“, einen „Zerfall“ oder auch Anzeichen eines „Sterbens“ der liberalen Demokratie zum Gegenstand haben. Es handelt sich um Abhandlungen, die vor dem Hintergrund der aktuellen Welle des Populismus verfasst worden sind. Die These dieses Besprechungsessays lautet, dass in diesen Büchern mehr eine Ratlosigkeit über die Zukunft der Demokratie beziehungsweise eine nostalgische Sehnsucht nach einer vermeintlich intakten liberalen Demokratie, als es die Populisten noch nicht gab, zum Ausdruck kommt, als dass es den Autorinnen und Autoren gelingt, überzeugende Auswege aus der gegenwärtigen „Krise“ aufzuzeigen. Kompensiert wird diese Leerstelle zumeist mit normativen Vergewisserungsfloskeln, etwa, dass gegen die Krise der Demokratie nur „mehr Demokratie“ helfe oder wir alle gemeinsam gegen die Feinde der Demokratie aufstehen müssten
Biomechanical models in the lower-limb exoskeletons development: a review
No full textLower limb exoskeletons serve multiple purposes, like supporting and augmenting movement. Biomechanical models are practical tools to understand human movement, and motor control. This paper provides an overview of these models and a comprehensive review of the current applications of them in assistive device development. It also critically analyzes the existing literature to identify research gaps and suggest future directions. Biomechanical models can be broadly classified as conceptual and detailed models and can be used for the design, control, and assessment of exoskeletons. Also, these models can estimate unmeasurable or hard-to-measure variables, which is also useful within the aforementioned applications. We identified the validation of simulation studies and the enhancement of the accuracy and fidelity of biomechanical models as key future research areas for advancing the development of assistive devices. Additionally, we suggest using exoskeletons as a tool to validate and refine these models. We also emphasize the exploration of model-based design and control approaches for exoskeletons targeting pathological gait, and utilizing biomechanical models for diverse design objectives of exoskeletons. In addition, increasing the availability of open source resources accelerates the advancement of the exoskeleton and biomechanical models. Although biomechanical models are widely applied to improve movement assistance and rehabilitation, their full potential in developing human-compatible exoskeletons remains underexplored and requires further investigation. This review aims to reveal existing needs and cranks new perspectives for developing more effective exoskeletons based on biomechanical models
Towards High-performance and Trusted Cloud DBMSs
No full textCloud Database Management Systems (DBMSs), such as cloud-native analytical or serverless DBs, are experiencing rapid growth in adoption due to their flexibility and scalability. However, recent incidents with cloud providers show that the traditional model of a trusted provider/admin no longer applies to protect the customers’ data. One promising solution that can prevent a sole reliance on cloud and database service providers are trusted execution environments (TEEs). While past TEEs had many limitations and caused high performance overheads, recent work shows that the support of TEEs like Intel SGX for DBMS workloads improved significantly. Thus, it is time to actively integrate TEE technologies into cloud DBMSs to achieve better security that does not rely on the cloud provider. In this paper, we discuss directions for how recent TEEs can be used to build efficient and secure databases. We summarize the recent results on Intel SGX’s performance for DBMS workloads and lay out the remaining research challenges that must be addressed to achieve optimal performance and thus minimize the performance cost for additional security
Quasi-real-time range monitoring by in-beam PET: a case for ¹⁵O
No full textA fast and reliable range monitoring method is required to take full advantage of the high linear energy transfer provided by therapeutic ion beams like carbon and oxygen while minimizing damage to healthy tissue due to range uncertainties. Quasi-real-time range monitoring using in-beam positron emission tomography (PET) with therapeutic beams of positron-emitters of carbon and oxygen is a promising approach. The number of implanted ions and the time required for an unambiguous range verification are decisive factors for choosing a candidate isotope. An experimental study was performed at the FRS fragment-separator of GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany, to investigate the evolution of positron annihilation activity profiles during the implantation of ¹⁴O and ¹⁵O ion beams in a PMMA phantom. The positron activity profile was imaged by a dual-panel version of a Siemens Biograph mCT PET scanner. Results from a similar experiment using ion beams of carbon positron-emitters ¹¹C and ¹⁰C performed at the same experimental setup were used for comparison. Owing to their shorter half-lives, the number of implanted ions required for a precise positron annihilation activity peak determination is lower for ¹⁰C compared to ¹¹C and likewise for ¹⁴O compared to ¹⁵O, but their lower production cross-sections make it difficult to produce them at therapeutically relevant intensities. With a similar production cross-section and a 10 times shorter half-life than ¹¹C, ¹⁵O provides a faster conclusive positron annihilation activity peak position determination for a lower number of implanted ions compared to ¹¹C. A figure of merit formulation was developed for the quantitative comparison of therapy-relevant positron-emitting beams in the context of quasi-real-time beam monitoring. In conclusion, this study demonstrates that among the positron emitters of carbon and oxygen, ¹⁵O is the most feasible candidate for quasi-real-time range monitoring by in-beam PET that can be produced at therapeutically relevant intensities. Additionally, this study demonstrated that the in-flight production and separation method can produce beams of therapeutic quality, in terms of purity, energy, and energy spread
From silos to synergy: improving coordination in local flood management
No full textFlood risk governance has gained increasing attention as climate change and urbanization amplify flood risks. While much of the literature has focused on national and supranational governance frameworks, sectoral integration, and public participation, there remains a critical gap in understanding horizontal coordination within municipal administrations—particularly in medium-sized cities. This study examines how local governments coordinate flood risk management across different departments and administrative units, identifying key challenges and enabling factors. Using a case study of Mörfelden-Walldorf, a medium-sized city in southern Hesse, Germany, we analyze the internal governance dynamics shaping flood resilience. The research highlights institutional fragmentation, sectoral silos, and resource constraints as key barriers to effective coordination while also identifying mechanisms that facilitate cross-departmental collaboration. By integrating insights from the public administration literature with flood governance scholarship, this study contributes to a more nuanced understanding of local-level flood risk governance. The findings provide practical implications for enhancing municipal flood resilience through improved governance structures and coordination mechanisms