@inproceedings{RiemannKlugChristetal., author = {Riemann, Janine and Klug, Katharina and Christ, Luisa and Stadler, Sebastian}, title = {Impact of Social Features on User Experience in Sport Tracking Applications}, series = {2025 11th International HCI and UX Conference in Indonesia (CHIuXiD), 05-06. December 2025, Bali, Indonesia}, booktitle = {2025 11th International HCI and UX Conference in Indonesia (CHIuXiD), 05-06. December 2025, Bali, Indonesia}, publisher = {IEEE}, isbn = {979-8-3315-5572-6}, doi = {10.1109/CHIuXiD68326.2025.11323615}, pages = {25 -- 30}, abstract = {Sport-tracking applications can enhance physical activity but may also induce stress through social comparison. This study examines how social comparison features influence user experience (UX), focusing on motivation, stress, and mental well-being. A survey of 101 German sport-tracking app users assessed intrinsic and extrinsic motivation, perceived stress, self-efficacy, enjoyment, social comparison orientation, and UX. Results reveal that higher social comparison consistently lowers intrinsic motivation, raises extrinsic motivation, and increases stress levels, while positive UX boosts intrinsic motivation and enjoyment and indirectly buffers stress. In particular, users who frequently evaluate their performance against others reported greater pressure to perform, heightened frustration, and a stronger focus on external validation. integrating adaptive feedback, and offering customizable social elements. Overall, the study contributes to understanding how UX and motivational dynamics interact in digital health tools and provides guidance for developing psychologically informed, health-oriented app environments. Conversely, app designs prioritizing mastery and personal progress over competitive ran kings foster autonomy, competence, and relatedness, supporting mental health and long-term adherence. These findings highlight the ambivalent effects of social features and underscore the need for sport-tracking apps to minimize harmful comparisons and promote self-determined motivation through supportive, user-friendly features. Practical implications include designing for sustainable engagement and well-being rather than exclusive competition.}, language = {en} } @inproceedings{BachirWeikl, author = {Bachir, Hussein and Weikl, Simone}, title = {Identifying Cyclist Riding Styles Using Drone-Based Trajectory Data and Volatility Clustering in Free-Flow Traffic Conditions}, series = {2025 IEEE 28th International Conference on Intelligent Transportation Systems (ITSC), 18-21. November 2025, Gold Coast, Australia}, booktitle = {2025 IEEE 28th International Conference on Intelligent Transportation Systems (ITSC), 18-21. November 2025, Gold Coast, Australia}, publisher = {IEEE}, isbn = {979-8-3315-2418-0}, doi = {10.1109/ITSC60802.2025.11423140}, pages = {233 -- 240}, abstract = {Cycling is increasingly promoted as a sustainable and healthy urban transportation mode. However, understanding cyclists' behavior remains underdeveloped compared to car drivers' behavior research. This paper proposes a two-level unsupervised clustering framework to identify cyclist riding styles in free flow conditions from drone-recorded trajectory data. The first level classifies local riding behavior at the timestamp level using riding volatility measures. The second level identifies overall cyclist behavior through clustering entropy measures, mean rotation fluctuation and surrounding traffic density at the trajectory level. The method was applied to a dataset of 284 trajectories and 100,000 data points from a 500-meter urban road segment in Munich, Germany and revealed two riding patterns on both levels: stable and volatile. The findings highlight the influence of road design clarity and behavioral variability and provide a foundation for cyclist-focused behavior and infrastructure analysis.}, language = {en} } @inproceedings{NorbisrathRossiJubehetal., author = {Norbisrath, Ulrich and Rossi, Bruno and Jubeh, Ruben and Heydarov, Araz}, title = {Multi-Stage Testing for Open Source IoT Frameworks}, series = {2025 IEEE International Conference on Systems, Man, and Cybernetics (SMC), 5-8. October 2025, Vienna}, booktitle = {2025 IEEE International Conference on Systems, Man, and Cybernetics (SMC), 5-8. October 2025, Vienna}, publisher = {IEEE}, isbn = {979-8-3315-3358-8}, doi = {10.1109/SMC58881.2025.11343478}, pages = {4685 -- 4690}, abstract = {The Internet of Things (IoT) has rapidly evolved, integrating networked intelligence into a web of things, servers, and cloudlets. Although there are various tools and approaches for software testing, the broader field of IoT testing presents unique challenges due to the heterogeneity of devices, large-scale deployments, dynamic environments, and real-time needs. This paper presents our approach to developing a multi-stage testing framework for the IoTempower framework, addressing the challenges of testing a versatile and evolving open-source Internet-of-Things framework used extensively in educational settings and beyond. The framework incorporates compilation testing, integration testing, and system testing with a focus on regression testing. This multi-stage testing approach allows us to validate the framework's functionality at various granularities, from the correct compilation of individual drivers to the seamless interaction of deployed hardware. This approach aims to proactively identify and prevent regressions, facilitating the integration of new features and enhancements without losing our scope of providing a real hands-on IoT experience in the classroom.}, language = {en} } @inproceedings{BarikRawatMannaetal., author = {Barik, Ranjan Kumar and Rawat, Vikram Singh and Manna, Subhrajit and Bandyopadhyay, Ayan Kumar and Hausladen, Matthias and Asgharzade, Ali and Schreiner, Rupert}, title = {On Chip Electron Gun Design Using Silicon Tip Field Emitter Array}, series = {2025 IEEE Microwaves, Antennas, and Propagation Conference (MAPCON), 14-18. Dezember 2025, Kochi, India}, booktitle = {2025 IEEE Microwaves, Antennas, and Propagation Conference (MAPCON), 14-18. Dezember 2025, Kochi, India}, publisher = {IEEE}, isbn = {979-8-3315-3722-7}, doi = {10.1109/MAPCON65020.2025.11426578}, pages = {4}, abstract = {Silicon based silicon tip array emitter has developed at OTH Regensburg, Germany. This array emitter is the basis for development of a novel electron gun. This field emitter electron sources were fabricated using laser-micromachining technique followed by MEMS technology. In this work, the design and development of electron gun using complete silicon structure is reported. The goal of this work is to develop electron gun using less effort, easy and hassle free technique.}, language = {en} } @article{TanSchreinerHausladenetal., author = {Tan, Jing Jie and Schreiner, Rupert and Hausladen, Matthias and Asgharzade, Ali and Edler, Simon and Bartsch, Julian and Bachmann, Michael and Schels, Andreas and Kwan, Ban-Hoe and Ng, Danny Wee-Kiat and Hum, Yan-Chai}, title = {SiMiC: Context-aware silicon microstructure characterization using attention-based convolutional neural networks for field-emission tip analysis}, series = {Journal of Vacuum Science \& Technology B}, volume = {43}, journal = {Journal of Vacuum Science \& Technology B}, number = {6}, publisher = {AVS}, doi = {10.1116/6.0005068}, abstract = {Accurate characterization of silicon microstructures is essential for advancing microscale fabrication, quality control, and device performance. Traditional analysis using scanning electron microscopy (SEM) often requires labor-intensive, manual evaluation of feature geometry, limiting throughput and reproducibility. In this study, we propose SiMiC: Context-aware Silicon Microstructure Characterization Using Attention-based Convolutional Neural Networks for Field-Emission Tip Analysis. By leveraging deep learning, our approach efficiently extracts morphological features—such as size, shape, and apex curvature—from SEM images, significantly reducing human intervention while improving measurement consistency. A specialized dataset of silicon-based field-emitter tips was developed, and a customized convolutional neural network architecture incorporating attention mechanisms was trained for multiclass microstructure classification and dimensional prediction. Comparative analysis with classical image processing techniques demonstrates that SiMiC achieves high accuracy while maintaining interpretability. The proposed framework establishes a foundation for data-driven microstructure analysis directly linked to field-emission performance, opening avenues for correlating emitter geometry with emission behavior and guiding the design of optimized cold-cathode and SEM electron sources. The related dataset and algorithm repository that could serve as a baseline in this area can be found at https://research.jingjietan.com/?q=SIMIC.}, language = {en} } @inproceedings{BielmeierRamsauerYoshidaetal., author = {Bielmeier, Benno and Ramsauer, Ralf and Yoshida, Takahiro and Mauerer, Wolfgang}, title = {From Tracepoints to Timeliness: a Semi-Markov Framework for Predictive Runtime Analysis}, series = {IEEE 31th International Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA), 20-22 August 2025, Singapore}, booktitle = {IEEE 31th International Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA), 20-22 August 2025, Singapore}, publisher = {IEEE}, doi = {10.1109/RTCSA66114.2025.00021}, pages = {114 -- 125}, abstract = {Detecting and resolving violations of temporal constraints in real-time systems is both, time-consuming and resource-intensive, particularly in complex software environments. Measurement-based approaches are widely used during development, but often are unable to deliver reliable predictions with limited data. This paper presents a hybrid method for worst-case execution time estimation, combining lightweight runtime tracing with probabilistic modelling. Timestamped system events are used to construct a semi-Markov chain, where transitions represent empirically observed timing between events. Execution duration is interpreted as time-to-absorption in the semi-Markov chain, enabling worst-case execution time estimation with fewer assumptions and reduced overhead. Empirical results from real-time Linux systems indicate that the method captures both regular and extreme timing behaviours accurately, even from short observation periods. The model supports holistic, low-intrusion analysis across system layers and remains interpretable and adaptable for practical use.}, language = {en} } @article{FeilnerRamsauer, author = {Feilner, Markus and Ramsauer, Ralf}, title = {Open-Source-Wissenschaftler bereiten Software f{\"u}r das Quantencomputing vor}, series = {Linux-Magazin}, volume = {25}, journal = {Linux-Magazin}, number = {08}, publisher = {Deloitte}, pages = {7}, abstract = {Um Software und Architekturen f{\"u}r das Quantencomputing zu entwickeln, zu definieren und zu testen, braucht man keinen Quantencomputer. Weil die teuer und rar sind, entschieden sich Wissenschaftler der OTH Regensburg daf{\"u}r, sie einfach zu virtualisieren - mit messbarem Erfolg.}, language = {en} } @inproceedings{SchmidbauerRiofrioHeinrichetal., author = {Schmidbauer, Lukas and Riofr{\´i}o, Carlos A. and Heinrich, Florian and Junk, Vanessa and Schwenk, Ulrich and Husslein, Thomas and Mauerer, Wolfgang}, title = {Path Matters: Industrial Data Meet Quantum Optimization}, series = {2025 IEEE International Conference on Quantum Computing and Engineering (QCE), 30 August - 05 September 2025, Albuquerque}, booktitle = {2025 IEEE International Conference on Quantum Computing and Engineering (QCE), 30 August - 05 September 2025, Albuquerque}, publisher = {IEEE}, doi = {10.1109/QCE65121.2025.00230}, pages = {2101 -- 2111}, abstract = {Real-world optimization problems must undergo a series of transformations before becoming solvable on current quantum hardware. Even for a fixed problem, the number of possible transformation paths-from industry-relevant formulations through binary constrained linear programs (BILPs), to quadratic unconstrained binary optimization (QUBO), and finally to a hardware-executable representation-is remarkably large. Each step introduces free parameters, such as Lagrange multipliers, encoding strategies, slack variables, rounding schemes or algorithmic choices-making brute-force exploration of all paths intractable. In this work, we benchmark a representative subset of these transformation paths using a realworld industrial production planning problem with industry data: the optimization of work allocation in a press shop producing vehicle parts. We focus on QUBO reformulations and algorithmic parameters for both quantum annealing (QA) and the Linear Ramp Quantum Approximate Optimization Algorithm (LR-QAOA). Our goal is to identify a reduced set of effective configurations applicable to similar industrial settings. Our results show that QA on D-Wave hardware consistently produces near-optimal solutions, whereas LR-QAOA on IBM quantum devices struggles to reach comparable performance. Hence, the choice of hardware and solver strategy significantly impacts performance. The problem formulation and especially the penalization strategy determine the solution quality. Most importantly, mathematically-defined penalization strategies are equally successful as hand-picked penalty factors, paving the way for automated QUBO formulation. Moreover, we observe a strong correlation between simulated and quantum annealing performance metrics, offering a scalable proxy for predicting QA behavior on larger problem instances.}, language = {en} } @article{FranzSchoenbergerStrobletal., author = {Franz, Maja and Sch{\"o}nberger, Manuel and Strobl, Melvin and K{\"u}hn, Eileen and Streit, Achim and Zurita, P{\´i}a and Diefenthaler, Markus and Mauerer, Wolfgang}, title = {From Hope to Heuristic: Realistic Runtime Estimates for Quantum Optimisation in NHEP}, series = {EPJ Web of Conferences; 27th International Conference on Computing in High Energy and Nuclear Physics (CHEP 2024)}, volume = {337}, journal = {EPJ Web of Conferences; 27th International Conference on Computing in High Energy and Nuclear Physics (CHEP 2024)}, publisher = {EDP Sciences}, doi = {10.1051/epjconf/202533701282}, pages = {8}, abstract = {Noisy Intermediate-Scale Quantum (NISQ) computers, despite their limitations, present opportunities for near-term quantum advantages in Nuclear and High-Energy Physics (NHEP) when paired with specially designed quantum algorithms and processing units. This study focuses on core algorithms that solve optimization problems through the quadratic Ising or Quadratic Unconstrained Binary Optimisation model, specifically Quantum Annealing and the Quantum Approximate Optimisation Algorithm (QAOA). In particular, we estimate runtimes and scalability for the task of particle Track Reconstruction (TR), a key computing challenge in NHEP, and investigate how the classical parameter space in QAOA, along with techniques like a Fourieranalysis based heuristic, can facilitate future quantum advantages. The findings indicate that lower frequency components in the parameter space are crucial for effective annealing schedules, suggesting that heuristics can improve resource efficiency while achieving near-optimal results. Overall, the study highlights the potential of NISQ computers in NHEP and the significance of co-design approaches and heuristic techniques in overcoming challenges in quantum algorithms.}, language = {en} } @unpublished{FranzStroblChaichenetsetal., author = {Franz, Maja and Strobl, Melvin and Chaichenets, Leonid and K{\"u}hn, Eileen and Streit, Achim and Mauerer, Wolfgang}, title = {Out of Tune: Demystifying Noise-Effects on Quantum Fourier Models}, doi = {10.48550/arXiv.2506.09527}, pages = {32}, abstract = {Variational quantum algorithms have received substantial theoretical and empirical attention. As the underlying variational quantum circuit (VQC) can be represented by Fourier series that contain an exponentially large spectrum in the number of input features, hope for quantum advantage remains. Nevertheless, it remains an open problem if and how quantum Fourier models (QFMs) can concretely outperform classical alternatives, as the eventual sources of non-classical computational power (for instance, the role of entanglement) are far from being fully understood. Likewise, hardware noise continues to pose a challenge that will persist also along the path towards fault tolerant quantum computers. In this work, we study VQCs with Fourier lenses, which provides possibilities to improve their understanding, while also illuminating and quantifying constraints and challenges. We seek to elucidate critical characteristics of QFMs under the influence of noise. Specifically, we undertake a systematic investigation into the impact of noise on the Fourier spectrum, expressibility, and entangling capability of QFMs through extensive numerical simulations and link these properties to training performance. The insights may inform more efficient utilisation of quantum hardware and support the design of tailored error mitigation and correction strategies. Decoherence imparts an expected and broad detrimental influence across all Ans{\"a}tze. Nonetheless, we observe that the severity of these deleterious effects varies among different model architectures, suggesting that certain configurations may exhibit enhanced robustness to noise and show computational utility.}, language = {en} } @article{MaschekSchwittallaFranzetal., author = {Maschek, Stefan Raimund and Schwittalla, J{\"u}rgen and Franz, Maja and Mauerer, Wolfgang}, title = {Make Some Noise! Measuring Noise Model Quality in Real-World Quantum Software}, series = {Proceedings of the IEEE International Conference on Quantum Software (QSW), 07-12 July 2025, Helsinki}, journal = {Proceedings of the IEEE International Conference on Quantum Software (QSW), 07-12 July 2025, Helsinki}, publisher = {IEEE}, doi = {10.1109/QSW67625.2025.00010}, pages = {11}, abstract = {Noise and imperfections are among the prevalent challenges in quantum software engineering for current NISQ systems. They will remain important in the post-NISQ area, as logical, error-corrected qubits will be based on software mechanisms. As real quantum hardware is still limited in size and accessibility, noise models for classical simulation-that in some cases can exceed dimensions of actual systems-play a critical role in obtaining insights into quantum algorithm performance, and the properties of mechanisms for error correction and mitigation. We present, implement and validate a tunable noise model building on the Kraus channel formalism on a large scale quantum simulator system (Qaptiva). We use empirical noise measurements from IBM quantum (IBMQ) systems to calibrate the model and create a realistic simulation environment. Experimental evaluation of our approach with Greenberger-Horne-Zeilinger (GHZ) state preparation and QAOA applied to an industrial usecase validate our approach, and demonstrate accurate simulation of hardware behaviour at reasonable computational cost. We devise and utilise a method that allows for determining the quality of noise models for larger problem instances than is possible with existing metrics in the literature. To identify potentials of future quantum software and algorithms, we extrapolate the noise model to future partially fault-tolerant systems, and give insights into the interplay between hardware-specific noise modelling and hardware-aware algorithm development.}, language = {en} } @article{StroblFranzKuehnetal., author = {Strobl, Melvin and Franz, Maja and K{\"u}hn, Eileen and Mauerer, Wolfgang and Streit, Achim}, title = {QML-Essentials: A Framework for Working with Quantum Fourier Models}, series = {Proceedings of the IEEE International Conference on Quantum Software (QSW), 07-12 July 2025, Helsinki}, journal = {Proceedings of the IEEE International Conference on Quantum Software (QSW), 07-12 July 2025, Helsinki}, publisher = {IEEE}, doi = {10.1109/QSW67625.2025.00035}, pages = {238 -- 243}, abstract = {In this work, we propose a framework in the form of a Python package, specifically designed for the analysis of Quantum Machine Learning models. This framework is based on the PennyLane simulator and facilitates the evaluation and training of Variational Quantum Circuits. It provides additional functionality ranging from the ability to add different types of noise to the classical simulation, over different parameter initialisation strategies, to the calculation of expressibility and entanglement for a given model. As an intrinsic property of Quantum Fourier Models, it provides two methods for calculating the corresponding Fourier spectrum: one via the Fast Fourier Transform and another analytical method based on the expansion of the expectation value using trigonometric polynomials. It also provides a set of predefined approaches that allow a fast and straightforward implementation of Quantum Machine Learning models. With this framework, we extend the PennyLane simulator with a set of tools that allow researchers a more convenient start with Quantum Fourier Models and aim to unify the analysis of Variational Quantum Circuits.}, language = {en} } @unpublished{PeriyasamyUfrechtSchereretal., author = {Periyasamy, Maniraman and Ufrecht, Christian and Scherer, Daniel D. D. and Mauerer, Wolfgang}, title = {CutReg: A loss regularizer for enhancing the scalability of QML via adaptive circuit cutting}, doi = {10.48550/arXiv.2506.14858}, pages = {4}, abstract = {Whether QML can offer a transformative advantage remains an open question. The severe constraints of NISQ hardware, particularly in circuit depth and connectivity, hinder both the validation of quantum advantage and the empirical investigation of major obstacles like barren plateaus. Circuit cutting techniques have emerged as a strategy to execute larger quantum circuits on smaller, less connected hardware by dividing them into subcircuits. However, this partitioning increases the number of samples needed to estimate the expectation value accurately through classical post-processing compared to estimating it directly from the full circuit. This work introduces a novel regularization term into the QML optimization process, directly penalizing the overhead associated with sampling. We demonstrate that this approach enables the optimizer to balance the advantages of gate cutting against the optimization of the typical ML cost function. Specifically, it navigates the trade-off between minimizing the cutting overhead and maintaining the overall accuracy of the QML model, paving the way to study larger complex problems in pursuit of quantum advantage}, language = {en} } @inproceedings{RamsauerBielmeierMauerer, author = {Ramsauer, Ralf and Bielmeier, Benno and Mauerer, Wolfgang}, title = {Towards Real-World System-Level Integration of Quantum Accelerators: A Hardware/Software Co-Design Approach}, series = {INFORMATIK; Lecture Notes in Informatics (LNI); GI Quantum Computing Workshop. Potsdam. 16.-19. September 2025}, booktitle = {INFORMATIK; Lecture Notes in Informatics (LNI); GI Quantum Computing Workshop. Potsdam. 16.-19. September 2025}, publisher = {Gesellschaft f{\"u}r Informatik e.V.}, doi = {10.18420/inf2025_158}, pages = {1761 -- 1765}, abstract = {This work-in-progress explores architectural and systemic foundations for integrating quantum accelerators into heterogeneous computing environments. We propose and implement a modular architecture where Quantum Processing Units (QPUs) operate as peripheral devices, supporting pulse-level control interfaces and high-level circuit execution offloading, while internally managing compilation, transpilation, and scheduling. To enable efficient quantum-classical orchestration, we introduce a Quantum Abstraction Layer (QAL) at the operating system level to enable seamless communication, resource management, and integration with existing software frameworks. Our two-step design approach begins with validating the architecture through simulations in virtualised environments. We then implement an FPGA-based surrogate supporting both result- and timing-accurate modes, enabling full-stack emulation and performance evaluation in the absence of physical quantum hardware. This platform supports extensible and rapid prototyping, Hardware/Software Co-Design, and allows for investigations on the practical quantum advantage under realistic system-level constraints of various use cases. We aim for applicability by hardware vendors, facilitating early development even before physical quantum processors are available.}, language = {en} } @unpublished{RamsauerMauerer, author = {Ramsauer, Ralf and Mauerer, Wolfgang}, title = {Towards System-Level Quantum-Accelerator Integration}, doi = {10.48550/arXiv.2507.19212}, pages = {6}, abstract = {Quantum computers are often treated as experimental add-ons that are loosely coupled to classical infrastructure through high-level interpreted languages and cloud-like orchestration. However, future deployments in both, high-performance computing (HPC) and embedded environments, will demand tighter integration for lower latencies, stronger determinism, and architectural consistency, as well as to implement error correction and other tasks that require tight quantum-classical interaction as generically as possible. We propose a vertically integrated quantum systems architecture that treats quantum accelerators and processing units as peripheral system components. A central element is the Quantum Abstraction Layer (QAL) at operating system kernel level. It aims at real-time, low-latency, and high-throughput interaction between quantum and classical resources, as well as robust low-level quantum operations scheduling and generic resource management. It can serve as blueprint for orchestration of low-level computational components "around" a QPU (and inside a quantum computer), and across different modalities. We present first results towards such an integrated architecture, including a virtual QPU model based on QEMU. The architecture is validated through functional emulation on three base architectures (x86_64, ARM64, and RISC-V), and timing-accurate FPGA-based simulations. This allows for a realistic evaluation of hybrid system performance and quantum advantage scenarios. Our work lays the ground for a system-level co-design methodology tailored for the next generation of quantum-classical computing.}, language = {en} } @inproceedings{SafiNiedermeierMauerer, author = {Safi, Hila and Niedermeier, Christoph and Mauerer, Wolfgang}, title = {TWiDDle: Twirling and Dynamical Decoupling, and Crosstalk Noise Modeling}, series = {2025 IEEE International Conference on Quantum Computing and Engineering (QCE), 30 August - 05 September 2025, Albuquerque}, booktitle = {2025 IEEE International Conference on Quantum Computing and Engineering (QCE), 30 August - 05 September 2025, Albuquerque}, publisher = {IEEE}, doi = {10.1109/QCE65121.2025.10313}, pages = {162 -- 168}, abstract = {Crosstalk remains a major source of correlated error in quantum systems, yet lacks a precise, community-wide definition - hindering systematic analysis and mitigation. This paper introduces a model-driven approach to crosstalk characterisation through three architecture-inspired noise models: (1) simultaneous two-qubit gate execution, (2) shared qubit interference, and (3) proximity-induced noise from shared control or readout hardware. These models act as both diagnostic tools and building blocks for crosstalk-aware quantum programming. We assess their impact across a broad benchmark suite - quantum simulation, Grover's algorithm, and fault-tolerant primitives like surface, Shor, and Steane codes - and evaluate two mitigation techniques: dynamical decoupling and Pauli twirling. While both are discussed in literature, only dynamical decoupling consistently enhances fidelity across noise types. Our work links low-level noise effects to high-level software engineering, underscoring the role of hardware-software co-design in scalable quantum computing. Model-based, hardware-aware design flows and composable noise abstractions improve error mitigation and program portability. Integrating such strategies into the toolchain is essential for building resilient quantum programs under realistic noise conditions.}, language = {en} } @inproceedings{SchmidbauerMauerer, author = {Schmidbauer, Lukas and Mauerer, Wolfgang}, title = {SAT Strikes Back: Parameter and Path Relations in Quantum Toolchains}, series = {Proceedings of the IEEE International Conference on Quantum Software (QSW), 07-12 July 2025, Helsinki}, booktitle = {Proceedings of the IEEE International Conference on Quantum Software (QSW), 07-12 July 2025, Helsinki}, publisher = {IEEE}, doi = {10.1109/QSW67625.2025.00021}, pages = {104 -- 115}, abstract = {In the foreseeable future, toolchains for quantum computing should offer automatic means of transforming a high level problem formulation down to a hardware executable form. Thereby, it is crucial to find (multiple) transformation paths that are optimised for (hardware specific) metrics. We zoom into this pictured tree of transformations by focussing on k-SAT instances as input and their transformation to QUBO, while considering structure and characteristic metrics of input, intermediate and output representations. Our results can be used to rate valid paths of transformation in advance—also in automated (quantum) toolchains. We support the automation aspect by considering stability and therefore predictability of free parameters and transformation paths. Moreover, our findings can be used in the manifesting era of error correction (since considering structure in a high abstraction layer can benefit error correcting codes in layers below). We also show that current research is closely linked to quadratisation techniques and their mathematical foundation.}, language = {en} } @inproceedings{ThelenMauerer, author = {Thelen, Simon and Mauerer, Wolfgang}, title = {Predict and Conquer: Navigating Algorithm Trade-Offs with Quantum Design Automation}, series = {2025 IEEE International Conference on Quantum Computing and Engineering (QCE), 30 August - 05 September 2025, Albuquerque}, booktitle = {2025 IEEE International Conference on Quantum Computing and Engineering (QCE), 30 August - 05 September 2025, Albuquerque}, publisher = {IEEE}, address = {Los Alamitos, USA}, doi = {10.1109/QCE65121.2025.00071}, pages = {591 -- 602}, abstract = {Combining quantum computers with classical compute power has become a standard means for developing algorithms and heuristics that are, eventually, supposed to beat any purely classical alternatives. While in-principle advantages for solution quality or runtime are expected for increasingly many approaches, substantial challenges remain: Non-functional properties like runtime or solution quality of many suggested approaches are not yet fully understood, and need to be explored empirically. This, in turn, makes it unclear which approach is best suited for a given problem. Accurately predicting behaviour and properties of quantum-classical algorithms opens possibilities for software abstraction layers, which in turn can automate decisionmaking for algorithm selection and parametrisation. While such techniques find frequent use in classical high-performance computing, they are still mostly absent from quantum software toolchains. In this paper, we present a methodology (accompanied by a reproducible reference implementation) to perform algorithm selection based on desirable non-functional requirements. This greatly simplifies decision-making processes for end users. Based on meta-information annotations at the source code level, our framework traces key characteristics of quantum-classical heuristics and algorithms, and uses this information to predict the most suitable approach and its parameters for given computational challenges and their non-functional requirements. As combinatorial optimisation is a very extensively studied aspect of quantumclassical systems, we perform a comprehensive case study based on numerical simulations of algorithmic approaches to implement and validate our ideas. We develop statistical models to quantify the influence of various factors on non-functional properties, and establish predictions for optimal algorithmic choices without manual user effort. We argue that our methodology generalises to problem classes beyond combinatorial optimisation, such as Hamiltonian optimisation, and lays a foundation for integrated software layers for quantum design automation.}, language = {en} } @inproceedings{KruegerMauerer, author = {Kr{\"u}ger, Tom and Mauerer, Wolfgang}, title = {Quantum Dark Magic: Efficiency of Intermediate Non-Stabiliserness}, series = {2025 IEEE International Conference on Quantum Computing and Engineering (QCE), 30 August- 05 September 2025, Albuquerque}, booktitle = {2025 IEEE International Conference on Quantum Computing and Engineering (QCE), 30 August- 05 September 2025, Albuquerque}, publisher = {IEEE}, doi = {10.1109/QCE65121.2025.10461}, pages = {592 -- 593}, abstract = {While quantum systems are know to possess inherent computational advantages over classical computers, constructing algorithms that harness such advantage remains an open challenge. Non-stabiliserness (i.e., traversal of states outside the Clifford orbit), is a necessary condition, as de-quantisation is otherwise possible. Nevertheless, an excess of non-stabiliserness is also known to not be advantageous. In this paper, we present an approach to understanding the efficient use of non-stabiliser states by tracking their behaviour across various algorithms. Our techniques reveal different efficiencies in the use of non-stabiliserness, leading us to hypothesise that greater classical optimisation degrees of freedom can introduce unnecessary non-stabiliser consumption, which becomes costly with error correction.}, language = {en} } @inproceedings{WeinzierlSchulz, author = {Weinzierl, Stefan and Schulz, Carsten}, title = {Digitaler Zwilling einer Doppelschlag-Verlitzmaschine : Digital twin of a double twist stranding machine}, series = {5. VDI-Fachtagung Schwingungen 2025}, booktitle = {5. VDI-Fachtagung Schwingungen 2025}, publisher = {VDI Verlag}, isbn = {9783181024638}, doi = {10.51202/9783181024638-271}, pages = {271 -- 288}, abstract = {Die Methode der Mehrk{\"o}rpersimulation und die Finite-Elemente-Methode gewinnen aufgrund immer leistungsf{\"a}higerer Rechentechnik in Forschung und Entwicklung zunehmend an Bedeutung. Heutzutage k{\"o}nnen komplexe Systeme mit diesen Methoden virtuell simuliert und multiphysikalisch untersucht werden. Insbesondere im Entwicklungsprozess f{\"u}hrt deren Einsatz aufgrund der damit verbundenen Zeit- und Kosteneinsparungen zu einem entscheidenden Wettbewerbsvorteil. Im Rahmen dieser Arbeit wird ein digitaler Zwilling einer bestehenden Doppelschlag-Verlitzmaschine erstellt. Ziel ist die virtuelle Durchf{\"u}hrung von Untersuchungen und Schwingungsanalysen. Die wichtigsten Komponenten werden mit flexiblen Eigenschaften unter der Verwendung der Finite-Elemente-Methode integriert, um die Schwingungsf{\"a}higkeit des Systems zu simulieren. Um die Effizienz der Simulation zu erh{\"o}hen, werden die flexiblen K{\"o}rper auf ein modales Ersatzmodell reduziert. Dar{\"u}ber hinaus wird die Nachgiebigkeit der Lagerpunkte durch Streifigkeitsmatrizen abgebildet und analysiert. F{\"u}r die Untersuchung des Hochlaufs und des Dauerbetriebes mit unterschiedlichen Maschinenkonfigurationen wurde ein Auswerteverfahren entwickelt, das die Reproduzierbarkeit und den Vergleich zwischen den einzelnen Tests erm{\"o}glicht. Abschließend erfolgt durch den Abgleich mit realen Messungen die Validierung des digitalen Zwillings, wodurch dessen Qualit{\"a}t gesichert und die Vergleichbarkeit zur realen Maschine gew{\"a}hrleistet wird.}, language = {de} } @inproceedings{HinterreiterRauchBrueckl, author = {Hinterreiter, Marion and Rauch, Johannes and Br{\"u}ckl, Oliver}, title = {Long-term reactive power forecasting power grids - Challenges and methodologies}, series = {Applied Research Conference - ARC 04.07.2025, Augsburg}, booktitle = {Applied Research Conference - ARC 04.07.2025, Augsburg}, pages = {6}, abstract = {The transition of power systems from fossil fuels to renewable energy sources is driving profound changes across all voltage levels of the electrical grid, altering active power (P) as well as reactive power (Q) behavior. This transformation involves a shift from predominantly top-down, unidirectional electricity flows to bidirectional and increasingly complex flow patterns, fundamentally altering the operation and utilization of power systems. The growing integration of distributed energy resources (DERs), heat pumps (HPs), and electric vehicles (EVs) is particularly impacting lower voltage levels, which are evolving from traditionally consumer-dominated networks into active participants in energy dynamics. These developments have a significant influence on reactive power behavior, with many countries already reporting notable changes due to increased Q contributions from lower voltage levels. As bidirectional flows and decentralized generation increase, understanding and forecasting reactive power trends at these voltage levels becomes essential for ensuring grid stability and efficiency. This paper addresses the challenges of long-term Q forecasting in general by analyzing reactive power behavior in grids, the main influencing grid parameters and introducing existing approaches and concepts, analyzing their applicability, and discussing the associated challenges and methodologies. By shedding light on this underexplored area, the study aims to contribute to the development of advanced long-term reactive power forecasting methods and highlighting research trends.}, language = {en} } @article{LambertKrausDoepfertetal., author = {Lambert, Jerry and Kraus, Hermann and Doepfert, Markus and He, Miaomiao and Gschossmann, David and Ceruti, Amedeo and Nemeth, Isabell and Br{\"u}ckl, Oliver and Hamacher, Thomas and Spliethoff, Hartmut}, title = {Assessing the techno-economic impact of district heating on electrical distribution grid reinforcements}, series = {Advances in Applied Energy}, volume = {20}, journal = {Advances in Applied Energy}, publisher = {Elsevier}, issn = {2666-7924}, doi = {10.1016/j.adapen.2025.100251}, pages = {21}, abstract = {Enhanced sector coupling across electricity, mobility, and heating sectors leads to higher efforts for distribution grid upgrades. Based on a case study, this paper evaluates the role of district heating networks in reducing electrical distribution grid reinforcements and compares their economic viability against a building-specific heat supply using heat pumps. A detailed energy system model is used to analyze two building energy renovation scenarios: a business-as-usual scenario with a 1 \% annual renovation rate and an ambitious scenario with a rate of 2 \%. Using a two-step optimization, the impact of different district heating network penetration levels on the distribution grid is evaluated, followed by an ex-post analysis to incorporate a simultaneity factor into district heating networks. Overall, district heating networks can reduce distribution grid reinforcements, but the associated savings alone do not justify their construction, particularly in the ambitious renovation scenario. In the business-as-usual scenario, a district heating network can reduce reinforcement costs by up to 71 \%. However, in the ambitious scenario, grid reinforcements are already reduced due to lower heat peak demand, and the maximal reinforcement cost savings only amount to 35 \%. Compared economically, district heating networks are cost-competitive with building-specific heating only in the business-as-usual scenario, up to a heat supply share of 70 \% and in the ambitious scenario, up to 40 \%. In both scenarios, a district heating network can be a robust solution to lower macroeconomic costs for a carbon-neutral heat supply.}, language = {en} } @misc{AppeltFautz, author = {Appelt, Andreas and Fautz, Anna}, title = {Optimierung Offenporiger Asphalte f{\"u}r Geh- und Radwegbereiche unter dem Aspekt der Schwammstadt}, address = {Regensburg}, pages = {47}, abstract = {Ans{\"a}tze zur planerische und bautechnische Optimierungen von inner{\"o}rtlichen Geh- und Radwegen mit Einsatz von Offenporigen Asphalten unter dem Aspekt der Schwammstadt}, language = {de} } @misc{OPUS4-7895, title = {Production Scheduling and Planning in Manufacturing Systems}, series = {Systems}, volume = {2025}, journal = {Systems}, editor = {Herrmann, Frank}, publisher = {MDPI}, address = {Basel}, issn = {2079-8954}, language = {en} } @inproceedings{HinterreiterBruecklRauch, author = {Hinterreiter, Marion and Br{\"u}ckl, Oliver and Rauch, Johannes}, title = {Challenges and Approaches for Long-Term Reactive Power Forecasting in Power Systems}, series = {PESS 2025 - IEEE Power and Energy Student Summit, October 08 - 10, 2025 in Munich, Germany}, booktitle = {PESS 2025 - IEEE Power and Energy Student Summit, October 08 - 10, 2025 in Munich, Germany}, editor = {Technische Universit{\"a}t M{\"u}nchen,}, publisher = {VDE Verlag}, isbn = {978-3-8007-6656-7}, pages = {109 -- 114}, abstract = {The transition from fossil fuels to renewable energy sources is driving profound changes across all voltage levels of the electrical grid, altering active power (P) as well as reactive power (Q) behavior. This transformation involves a shift from predominantly top-down, unidirectional electricity flows to bidirectional and increasingly complex flow patterns, fundamentally altering the operation and utilization of power systems. Many countries are already reporting notable changes in their transmission grid Q. This can lead to increased costs for grid expansion and compensation equipment, as well as grid losses. To minimize these losses and ensure grid stability and efficiency, understanding and forecasting Q long-term becomes essential. This paper addresses the challenges of long-term (1-20 years) Q forecasting in general by analyzing Q behavior in grids, the main influencing grid parameters, and reviewing existing forecasting approaches. It evaluates the applicability of these approaches and highlights current research gaps and trends. By focusing on this underexplored area, the paper aims to support the development of more advanced and reliable long-term Q forecasting techniques.}, language = {en} } @inproceedings{HinterreiterBruecklRauch, author = {Hinterreiter, Marion and Br{\"u}ckl, Oliver and Rauch, Johannes}, title = {Methodology for long-term reactive power forecasts of medium-voltage grids}, series = {NEIS 2025 : Conference on Sustainable Energy Supply and Energy Storage Systems, Hamburg, September 15 - 16, 2025}, booktitle = {NEIS 2025 : Conference on Sustainable Energy Supply and Energy Storage Systems, Hamburg, September 15 - 16, 2025}, editor = {Schulz, Detlef}, publisher = {VDE Verlag}, isbn = {978-3-8007-6633-8}, pages = {218 -- 223}, abstract = {Understanding and assessing the long-term behavior of reactive power is crucial for power system planning and invest-ment decisions. This is particularly growing relevant for the lower voltage-grid levels, which are gaining importance due to significant changes in grid behavior, operational strategies, energy generation and consumption patterns. Currently, standardized methodologies for forecasting reactive power in medium-voltage grids are lacking, creating a gap in research and practical applications. To optimize grid investments and expansions, informed decisions based on reliable research and accurate forecasts are essential. This paper presents a methodology for long-term reactive power forecasting in me-dium-voltage grids, introducing a new approach to account for low- and medium-voltage grid interactions while address-ing common challenges like limited available grid data and scenario framework definition. The aim of the forecast is the future reactive power behaviour of a medium-voltage-grid at the high-voltage side of the high-voltage to medium-voltage transformer. The medium-voltage-level is modelled using a grid model approach, while low-voltage grids are being mod-elled using generic distribution grids. A 209-bus medium-voltage-grid model is used as an application example and to provide two exemplary use cases for a reactive power forecast for 2045.}, language = {en} } @inproceedings{StadlerKrausBrueckl, author = {Stadler, Andreas and Kraus, Hermann and Br{\"u}ckl, Oliver}, title = {Proposing an Optimization Model for a techno-economic Evaluation of Energy Storage Systems}, series = {PESS 2025 - IEEE Power and Energy Student Summit, October 08 - 10, 2025 in Munich, Germany}, booktitle = {PESS 2025 - IEEE Power and Energy Student Summit, October 08 - 10, 2025 in Munich, Germany}, editor = {Technische Universit{\"a}t M{\"u}nchen,}, publisher = {VDE}, isbn = {978-3-8007-6656-7}, pages = {97 -- 102}, abstract = {During the global energy crisis in 2022, electricity prices increased drastically. This lead, together with an overall higher price volatility to possibly higher electrical energy storage system (ESS) profitability. To test if the investment in an ESS can now be more profitable, an approach for a techno-economic evaluation of ESS is presented in this paper, using an optimization algorithm to determine the optimal way of covering a load flow profile with electricity trading products on the electricity market with and without the use of an energy storage system. The cost differences between using or not using the storage system are assumed to be the profits of the ESS, which must exceed the (interest-bearing) investment costs over its lifetime. The correct way of operation of the optimization model is validated and several storage sizes and capacities as well as several years of the electricity market data was analyzed, once with a perfect forecast of all prices of the electricity trading products and once with a forecast based on the previous years purchasing strategy. The results show that, using the prognosis and a 2 \% p.a. interest rate, only the storage combinations for 2.5 MWh/ 2.5 MW and 1 MWh/ 1 MW show profitability in 2023, whereas 2017 and 2020 show no profitability.}, language = {en} } @inproceedings{UhlSchamelAchhammeretal., author = {Uhl, Julius and Schamel, Marco and Achhammer, Anton and Sterner, Michael}, title = {Sustainable Steel Production in the Desert: Economic and Technical Assessment of a Hydrogen-Powered Steel Plant in Mauritania}, series = {2025 IEEE PES/IAS PowerAfrica, 28 September - 02 October 2025, Cairo}, booktitle = {2025 IEEE PES/IAS PowerAfrica, 28 September - 02 October 2025, Cairo}, publisher = {IEEE}, doi = {10.1109/PowerAfrica65840.2025.11289120}, pages = {6}, abstract = {The global steel industry is a major contributor to climate change and faces challenges in achieving a carbon-neutral production, hinging on the availability of cost-effective hydrogen produced by renewable energy. Mauritania, with its exceptional solar and wind resources, offers some of the most competitive conditions globally for hydrogen production. Instead of focusing on hydrogen exports, this study explores the technical feasibility and economic viability of establishing a renewable-powered steel plant in Mauritania, utilizing the country's abundant iron ore reserves. The findings suggest that sustainably produced steel in Mauritania could be cost-competitive with current European prices. With ongoing declines in investment costs for emerging renewable technologies, Mauritania has the potential to become one of the world's most cost-effective steel producers.}, language = {en} } @book{FinckhKreutzEberth, author = {Finckh, Wolfgang and Kreutz, Johannes and Eberth, Florian}, title = {Br{\"u}ckenverst{\"a}rkung mit geklebter Bewehrung}, publisher = {Springer Vieweg}, address = {Wiesbaden}, isbn = {9783658492571}, doi = {10.1007/978-3-658-49258-8}, pages = {XVII, 317}, abstract = {Dieses Buch widmet sich der Verst{\"a}rkung von Stahlbeton- und Spannbetonbr{\"u}cken mit geklebter Bewehrung. Dazu werden zun{\"a}chst die verschieden Verst{\"a}rkungsgr{\"u}nde f{\"u}r Br{\"u}cken sowie deren Beanspruchungsarten vorgestellt. Danach werden die Anwendungsm{\"o}glichkeiten der geklebten Bewehrung vorgestellt und die rechnerischen Herausforderungen sowie der L{\"o}sungsm{\"o}glichkeiten erl{\"a}utert. Im n{\"a}chsten Kapitel wird vertieft auf die rechnerischen Besonderheiten von Spannbetonverst{\"a}rkungen mit geklebter Bewehrung eingegangen. Da f{\"u}r die Verbundnachweise der geklebten Bewehrung im Br{\"u}ckenbau einen Betriebsfestigkeit notwendig ist, wird dieser zun{\"a}chst am Stahlbetonbauteil erl{\"a}utert. Danach werden die erforderlichen Erm{\"u}dungsnachweise f{\"u}r aufgeklebte und eingeklebte Bewehrung im Br{\"u}ckenbau behandelt. Abschließend wird noch ein Verfahren vorgestellt, wie spannungsrisskorrosionsgef{\"a}hrdete Bauteile verst{\"a}rkt werden k{\"o}nnen. Die im Buch vorgestellten theoretischen Grundlagen werden anhand zahlreicher Abbildungen verdeutlicht. Zu jedem Thema sind zum besseren Verst{\"a}ndnis umfangreiche Bemessungsbeispiele mit Praxisbezug enthalten.}, language = {de} } @book{Finckh, author = {Finckh, Wolfgang}, title = {Mit Stabwerkmodellen zur Bewehrungsf{\"u}hrung: Detailnachweise im Stahlbetonbau}, series = {erfolgreich studieren}, journal = {erfolgreich studieren}, edition = {2. Auflage}, publisher = {Springer Fachmedien}, address = {Wiesbaden}, isbn = {9783658488550}, issn = {2524-8693}, doi = {10.1007/978-3-658-48856-7}, pages = {XIV, 465}, abstract = {Aufbauend auf den Grundlagen des Stahlbetonbaus wird in diesem Lehrbuch das Konzept der Bemessung von Stahlbetonkonstruktionen mittels Stabwerkmodellen erl{\"a}utert. Dieses Bemessungskonzept wird insbesondere im Bereich der Detailnachweise und bei gedrungenen Tragwerken im Stahlbetonbau ben{\"o}tigt. Neben der generellen Modellbildung und Nachweismethodik werden auch die {\"u}blichen Modelle und Nachweise f{\"u}r h{\"a}ufig vorkommende Details vorgestellt. Hierbei werden insbesondere Krafteinleitungsbereiche, Konsolen, ausgeklinkte Auflager, Rahmenknoten, Querschnittsspr{\"u}nge, Tr{\"a}ger{\"o}ffnungen, Wandartige Tr{\"a}ger, K{\"o}cherfundamente und Pfahlkopfplatte detailliert behandelt. Die im Lehrbuch vorgestellten theoretische Grundlagen werden anhand zahlreicher Abbildungen erl{\"a}uterten. In jedem Kapitel sind zum besseren Verst{\"a}ndnis umfangreiche Bemessungsbeispiele mit Praxisbezug enthalten.}, language = {de} } @article{SchiekSolntsevNeshev2025, author = {Schiek, Roland and Solntsev, Alexander S. and Neshev, Dragomir N.}, title = {Measurement of the cubic nonlinear susceptibility in lithium niobate}, series = {Optical Materials Express}, volume = {15}, journal = {Optical Materials Express}, number = {5}, publisher = {Optica Publishing Group}, issn = {2159-3930}, doi = {10.1364/OME.557516}, pages = {1100 -- 1117}, year = {2025}, abstract = {We measured the cubic nonlinear susceptibility tensor elements ( χ(3)) for polarization along the primary crystallographic axis in titanium-indiffused lithium niobate waveguides, assessed through self-phase modulation using picosecond-duration pulses at telecommunication wavelengths. A dominant, highly temperature- and wavelength-dependent contribution from a cascaded second-order nonlinearity is observed. Through careful extraction of the cascaded effect, we quantify the intrinsic third-order susceptibility tensor elements as χ(3) zzzz(ω; ω, ω, -ω) = (5.2 ± 1.3) × 10-21 m2 V2 and χ(3) xxxx(ω; ω, ω, -ω) = χ(3) yyyy(ω; ω, ω, -ω) = (3.6 ± 0.8) × 10-21 m2 V2 . These measurements underscore the substantial impact of the cascaded nonlinearity in enhancing the effective cubic nonlinearity in lithium niobate and offer precise values essential for the design of nonlinear photonic devices.}, language = {en} } @article{LinnerdeSotoElMahdyetal., author = {Linner, Thomas and de Soto, Borja Garc{\´i}a and El-Mahdy, Deena and Gonzalez, Vicente A.}, title = {Topical collection: robotic solutions for digitally enabled production processes in construction}, series = {Construction Robotics}, volume = {10}, journal = {Construction Robotics}, publisher = {Springer}, issn = {2509-811X}, doi = {10.1007/s41693-025-00174-w}, pages = {1}, abstract = {Across the global construction sector, a new generation of robotic systems is rapidly entering the market. Solutions for on-site drilling, spraying, masonry, logistics, and finishing are now being piloted at an unprecedented pace. Their deployment in emerging construction robotics hubs in Singapore, Hong Kong, Canada, Dubai, Abu Dhabi, Egypt, Denmark, Switzerland, and Germany demonstrates both the momentum of this technological shift and the considerable challenges that remain. In real-world testing environments, the integration of these robots into digital construction pipelines—particularly BIM-to-robot workflows, semantic task modeling, and robust digital twins—continues to be a bottleneck. These challenges position digitally enabled fabrication and robotics as a priority topic within academia, motivating research on methods, techniques, algorithms, and workflows that can accelerate adoption in construction. This Topical Collection brings together research spanning the emerging landscape of digitally enabled construction robotics. The contributions advance robotic fabrication, from flexible timber processes to innovative formwork, reinforcement, and earth-based additive methods, alongside computer vision, BIM integration, and sensing approaches that improve monitoring and quality assurance. The collection also includes mobile and aerial systems for inspection and mapping to support system autonomy in construction. Together, these works show how integrated perception, planning, and sociotechnical understanding of human-robot collaboration are becoming essential for reliable robotic performance in construction. While current construction robots still focus on simple, structured tasks, the advances in this topical collection point toward a more capable generation. Contributions outline principles for robot-compatible buildings through new fabrication logics and BIM-linked task data, while work on perception, BIM integration, and data fusion reduces interoperability gaps. Research on sensing and adaptive processes supports more consistent workflows, and mobile and aerial robotics provide insights for deployment and site logistics. Collectively, these developments show how digitally enabled production processes can help to overcome key systemic barriers and enable future, scalable construction robotics.}, language = {en} } @article{WeindlerLehnerEcksteinetal., author = {Weindler, Jeremy and Lehner, Hannes and Eckstein, J. and Dawoud, Belal}, title = {Performance assessment of a green hydrogen-based household energy system supported by a battery storage at different resolutions of the electrical load profile}, series = {International Journal of Hydrogen Energy}, volume = {144}, journal = {International Journal of Hydrogen Energy}, publisher = {Elsevier}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2025.04.431}, pages = {30 -- 41}, abstract = {Hydrogen deems quite suitable for medium- and long-term energy storage of surplus renewable electricity. Nowadays, all-in-one solutions consisting of an electrolyzer, a compressor, pressurized hydrogen storage tanks, a fuel cell (FC) and the necessary peripheral components are available for single family houses. This work presents a comparative assessment of the system's key performance indicators in a household system with three market available FCs with the nominal powers of 0.8, 1.4 and 7.8 kW. The design tool developed for the assessment of the hybrid energy system along with two energy management system configurations are introduced. An electrochemical and thermal model widely applied in the literature is used to model the FCs, which is validated against the available experimental data in the literature for all three FCs. The influence of the FCs' nominal power, their power dynamic operation range, the use of a battery storage with different capacities and the load profile's resolution have been technically assessed regarding the system's self-sufficiency (SS), the FC's efficiency, full-load operating hours, and number of on/off cycles. It turned out that, the system performance is strongly dependent on the nominal power of the FC and its power dynamic operation range. If no battery-storage is applied, the complete grid independence is not possible, and a high resolution of the load profile is indispensable in the assessment of the system design. A hybrid energy system comprising the 1.4 kW FC, a PV system of 10 kW peak power and a battery of 15 kW storage capacity showed a degree of SS of 98\%. The number of the full-load operating hours and on/off cycles of that FC amount to 768 and 116 cycles, respectively. Such promising results are referred to the high dynamic operation range of the battery, and its high discharge power capacity, which makes it more suitable to cover a remarkably higher fraction of the load deficit, if compared to a system without a battery.}, language = {en} }