@article{59797, author = {{Konopik, Michael and T. Sato Martín de Almagro, Rodrigo and Maslovskaya, Sofya and Ober-Blöbaum, Sina and Leyendecker, Sigrid}}, journal = {{Journal of Nonlinear Science}}, number = {{11}}, title = {{{Variational integrators for a new Lagrangian approach to control affine systems with a quadratic Lagrange term}}}, doi = {{10.1007/s00332-025-10229-5}}, volume = {{36}}, year = {{2025}}, } @article{59799, author = {{Konopik, Michael and Leyendecker, Sigrid and Maslovskaya, Sofya and Ober-Blöbaum, Sina and T. Sato Martín de Almagro, Rodrigo}}, journal = {{Nonlinearity}}, number = {{11}}, title = {{{A new Lagrangian approach to optimal control of second-order systems}}}, doi = {{10.1088/1361-6544/ae1d08}}, volume = {{38}}, year = {{2025}}, } @article{63091, abstract = {{We present the design and characterization of a guided-wave, bright, and highly frequency non-degenerate parametric down-conversion (PDC) source in thin-film lithium niobate. The source generates photon pairs with wavelengths of 815 nm and 1550 nm, linking the visible wavelength regime with telecommunication wavelengths. We confirm the high quality of the generated single photons by determining a value for the heralded second-order correlation function as low as g_h^(2)=(6.7+/-1.1)*10^8-3). Furthermore, we achieve a high spectral brightness of 0.44·10pairs/(smWGHz) which is two orders of magnitude higher than sources based on weakly guiding waveguides. The shape of the PDC spectrum and the strong agreement between the effective and nominal bandwidth highlight our high fabrication quality of periodically poled waveguides. The good agreement between the measured and simulated spectral characteristics of our source demonstrates our excellent understanding of the PDC process. Our result is a valuable step towards practical and scalable quantum communication networks as well as photonic quantum computing.}}, author = {{Babel, Silia and Bollmers, Laura and Roeder, Franz and Ridder, Werner and Golla, Christian and Köthemann, Ronja and Reineke, Bernhard and Herrmann, Harald and Brecht, Benjamin and Eigner, Christof and Padberg, Laura and Silberhorn, Christine}}, issn = {{1094-4087}}, journal = {{Optics Express}}, number = {{25}}, publisher = {{Optica Publishing Group}}, title = {{{Ultrabright, two-color photon pair source based on thin-film lithium niobate for bridging visible and telecom wavelengths}}}, doi = {{10.1364/oe.571605}}, volume = {{33}}, year = {{2025}}, } @article{62713, abstract = {{Periodically poled thin-film lithium niobate (TFLN) crystals are the fundamental building block for highly-efficient quantum light sources and frequency converters. The efficiency of these devices is strongly dependent on the interaction length between the light and the nonlinear material, scaling quadratically with this parameter. Nevertheless, the fabrication of long, continuously poled areas in TFLN remains challenging, the length of continuously poled areas rarely exceeds 10 mm. In this work, we demonstrate a significant progress in this field achieving the periodic poling of continuous poled areas of 70 mm length with a 3 μm poling period and a close to 50 % duty cycle. We compare two poling electrode design approaches to fabricate long, continuous poled areas. The first approach involves the poling of a single, continuous 70 mm long electrode. The second utilize a segmented approach including the poling of more than 20 individual sections forming together a 70 mm long poling area with no stitching errors. While the continuous electrode allows for faster fabrication, the segmented approach allows to individually optimize the poling resulting in less duty cycle variation. A detailed analysis of the periodic poling results reveals that the results of both are consistent with previously reported poling outcomes for shorter devices. Thus, we demonstrate wafer-scale periodic poling exceeding chiplet-size without any loss in the periodic poling quality. Our work presents a key step towards highly-efficient, narrow-bandwidth and low-pump power nonlinear optical devices.}}, author = {{Bollmers, Laura and Spiegelberg, Noah and Rüsing, Michael and Eigner, Christof and Padberg, Laura and Silberhorn, Christine}}, issn = {{2192-8606}}, journal = {{Nanophotonics}}, pages = {{4761}}, publisher = {{Walter de Gruyter GmbH}}, title = {{{Segmented finger electrodes to optimize ultra-long continuous wafer-scale periodic poling in thin-film lithium niobate}}}, doi = {{10.1515/nanoph-2025-0461}}, volume = {{14}}, year = {{2025}}, } @article{63518, author = {{Hagengruber, Ruth Edith}}, journal = {{ZDPE}}, publisher = {{Bettina Bussmann und Vanessa Albus}}, title = {{{Eine Demokratie, die das Recht der Frauen nicht verwirklicht, ist nichtig". Das politische Meisterstücke der Olympe de Gouges (1748-1793)}}}, volume = {{3}}, year = {{2025}}, } @inproceedings{63524, abstract = {{Recommendation systems are essential for delivering personalized content across e-commerce and streaming services. However, traditional methods often fail in cold-start scenarios where new items lack prior interactions. Recent advances in large language models (LLMs) offer a promising alternative. In this paper, we adopt the retrieve-and-recommend framework and propose to fine-tune the LLM jointly on warm-and cold-start next-item recommendation tasks, thus, mitigating the need for separate models for both item types. We computationally compare zero-shot prompting, in-context learning, and fine-tuning using the same LLM backbone, and benchmark them against strong PLM-based baselines. Our findings provide practical insights into the trade-offs between accuracy and computational cost of these methods for next-item recommendation. To enhance reproducibility, we release the source code under https://github. com/HayaHalimeh/LLMs-For-Next-Item-Recommendation.git.}}, author = {{Halimeh, Haya and Freese, Florian and Müller, Oliver}}, booktitle = {{International Conference on Information Systems Development}}, issn = {{2938-5202}}, publisher = {{University of Gdansk, Department of Business Informatics & University of Belgrade, Faculty of Organizational Sciences}}, title = {{{LLMs For Warm and Cold Next-Item Recommendation: A Comparative Study across Zero-Shot Prompting, In-Context Learning and Fine-Tuning}}}, doi = {{10.62036/isd.2025.68}}, year = {{2025}}, } @inproceedings{63523, abstract = {{Data spaces have become a strategic pillar of Europe's digital agenda, enabling sovereign, legally compliant data sharing within decentralized ecosystems. As data space initiatives evolve, personalized recommendations are increasingly recognized as key use cases. However, traditional recommendation approaches typically rely on centralized aggregation of user behavior data-directly conflicting with the core ethos of data spaces: sovereignty, privacy, and trust. Federated recommendation systems offer a promising alternative by training models locally and exchanging only intermediate parameters to build a global model. Despite this potential, the integration of federated recommendation techniques and data space architectures remains largely underexplored in research and practice. This paper addresses this gap by designing and evaluating a prototype of a federated recommendation system specifically tailored for data spaces and compliant with their underlying infrastructure. Our findings highlight the viability of developing privacy-preserving, collaborative recommendation systems within data spaces, and contribute to the broader adoption of AI across these emerging ecosystems.}}, author = {{Halimeh, Haya and zur Heiden, Philipp}}, booktitle = {{2025 27th International Conference on Business Informatics (CBI)}}, publisher = {{IEEE}}, title = {{{Preserving Sovereignty and Privacy for Personalization: Designing a Federated Recommendation System for Data Spaces}}}, doi = {{10.1109/cbi68102.2025.00019}}, year = {{2025}}, } @inproceedings{63525, abstract = {{Recommender systems (RS) can support sustainable development by steering users toward more sustainable choices. Sustainability-aware explanations represent one avenue for contributing to this goal by foregrounding the environmental and social aspects of the recommended products or services. This paper advances the line of research on sustainability-aware explanations by integrating nudging mechanisms into their design and by evaluating their effectiveness through a randomized between-subjects online vignette experiment across two item domains (). Our findings offer actionable design guidelines for building RS that foster sustainability-aware decision making and enrich the empirical foundation for impact-oriented research on explanation in RS. }}, author = {{Halimeh, Haya and Müller, Oliver}}, location = {{Prague, Czech Republic}}, title = {{{Towards Greener Choices: Decision Information Nudging for Sustainability-Aware Recommender Explanations}}}, doi = {{10.1007/978-3-032-13342-7}}, year = {{2025}}, } @unpublished{61922, abstract = {{We present an extremely simple polynomial-space exponential-time $(1-\varepsilon)$-approximation algorithm for MAX-k-SAT that is (slightly) faster than the previous known polynomial-space $(1-\varepsilon)$-approximation algorithms by Hirsch (Discrete Applied Mathematics, 2003) and Escoffier, Paschos and Tourniaire (Theoretical Computer Science, 2014). Our algorithm repeatedly samples an assignment uniformly at random until finding an assignment that satisfies a large enough fraction of clauses. Surprisingly, we can show the efficiency of this simpler approach by proving that in any instance of MAX-k-SAT (or more generally any instance of MAXCSP), an exponential number of assignments satisfy a fraction of clauses close to the optimal value.}}, author = {{Buhrman, Harry and Gharibian, Sevag and Landau, Zeph and Gall, François Le and Schuch, Norbert and Tamaki, Suguru}}, booktitle = {{SIAM Symposium on Simplicity in Algorithms (SOSA)}}, title = {{{A Simpler Exponential-Time Approximation Algorithm for MAX-k-SAT}}}, year = {{2025}}, } @techreport{63026, author = {{Althaus, Maike and Beverungen, Daniel and Flath, Beate and Halimeh, Haya and Hansmeier, Philipp and zur Heiden, Philipp and Kundisch, Dennis and Müller, Michelle and Müller, Oliver and Oberthür, Simon and Vorbohle, Christian and Momen Pour Tafreshi, Maryam and Mauß, Sebastian and Mücke, Alina and Müller, Jörg and Peter, Malte and Schmitt-Chandon, Ariane and Sellerberg, Kerstin and Steinhäuser, Moritz}}, title = {{{Positionspapier Use Case 1: Vernetzte Kulturplattformen}}}, year = {{2025}}, } @inproceedings{63527, author = {{Henkenjohann, Mark and Nolte, Udo and Jahneke, Julien and Reimer, Oliver and Abrams, Stefan and Sion, Fabian and Henke, Christian and Trächtler, Ansgar and Schubert, Sebastian and Pfifer, Harald}}, booktitle = {{AIAA SCITECH 2025 Forum}}, publisher = {{American Institute of Aeronautics and Astronautics}}, title = {{{Dynamic Wind Tunnel Testing of an INDI-Based Flight Controller for a Tiltrotor-VTOL}}}, doi = {{10.2514/6.2025-2083}}, year = {{2025}}, } @inproceedings{63528, author = {{Reiling, Fabian and Bause, Maximilian and Gröger, Stefan and Henke, Christian and Koppert, Steven and Trächtler, Ansgar}}, booktitle = {{2025 11th International Conference on Automation, Robotics, and Applications (ICARA)}}, publisher = {{IEEE}}, title = {{{Development of a Learning-Based Control System for Robot-Assisted Grinding of Rubber Roller}}}, doi = {{10.1109/icara64554.2025.10977606}}, year = {{2025}}, } @article{62652, abstract = {{Driven by the urgent need for a green, safe, and cost‐effective approach to producing H2 and H2O2—both highly valuable in green energy and environmental protection fields—piezocatalysis, which converts mechanical energy into valuable chemicals, has emerged as a promising solution. However, current catalyst systems face challenges due to the need for materials with both a strong piezoelectric effect and favorable catalytic activity. Herein, the construction of an oxidized carbon nitride (g‐C3N4) matrix anchored with TiO2 nanoparticles via alkaline hydrothermal treatment is reported. Under ultrasonication, the g‐C3N4/TiO2 composite exhibits optimal performance under carefully controlled alkaline hydrothermal conditions. With a low concentration of Ba(OH)2 during hydrothermal treatment, Ba(OH)2 provides an alkaline medium, oxidizing the g‐C3N4 species and introducing structural defects into the g‐C3N4 framework. The disruption of the g‐C3N4 matrix, along with its interaction with TiO2 nanoparticles, enhances the piezoelectric effect. Consequently, the oxidized g‐C3N4/TiO2 composite achieves a remarkable H2 production rate of 4427.2 μmol g−1 and an H2O2 production rate of 809.3 μmol g−1 within 1 h without the addition of any sacrificial agents or cocatalysts. This work presents an effective strategy for the structural optimization of g‐C3N4‐based materials and may inspire new approaches for designing advanced piezocatalysts.}}, author = {{Pan, Ying and Liao, Luocheng and Zhang, Xinwen and Liu, Yunya and Su, Ran and Lopez Salas, Nieves}}, issn = {{1864-5631}}, journal = {{ChemSusChem}}, number = {{19}}, publisher = {{Wiley}}, title = {{{Oxidation‐Enhanced Piezocatalytic Activity in Carbon Nitride‐Based Catalysts for Hydrogen and Hydrogen Peroxide Production}}}, doi = {{10.1002/cssc.202500980}}, volume = {{18}}, year = {{2025}}, } @article{62654, abstract = {{Abstract Cationic gold catalyzed acetylene hydrochlorination represents a classical landmark in eliminating global mercury pollution, but their sustainable implementation is hindered by acetylene‐dependence design criteria and high operating temperatures. Herein, a platform of carbon‐supported single‐atoms Au catalysts (Au/BC and Au/NC) with polarized charge characteristics are developed via engineering Au sites with hosted B, N configurations. The negatively charged Au/BC catalyst unlocks the low‐temperature inactivity (413–423K) of the Au/NC catalyst while exhibiting superior catalytic performance in the 433–473K operating temperature range. We confirm that the classical scaling relationships on acetylene can be broken by narrowing the adsorption capacity between acetylene and HCl on Au δ⁻ sites via facilitating the back‐donation of d electrons into the antibonding orbitals of acetylene. Prolonging the durability of Au catalysts is achieved through preceding an additional robust Au δ⁻ → Au δ⁺ cycle prior to the classic Au δ⁺ → Au 0 route. This work opens a promising avenue for low temperature vinyl chloride production. }}, author = {{Li, Chun and Liu, Ruoting and Zhang, Zilong and Zuo, Fangmin and Jiang, Tingting and Zhang, Haifeng and Wang, Bolin and Lopez Salas, Nieves}}, issn = {{1433-7851}}, journal = {{Angewandte Chemie International Edition}}, number = {{29}}, publisher = {{Wiley}}, title = {{{Engineering Charge Polarized Au Sites for Low‐Temperature Acetylene Hydrochlorination}}}, doi = {{10.1002/anie.202501370}}, volume = {{64}}, year = {{2025}}, } @article{62651, abstract = {{ Aqueous zinc (Zn)‐ion capacitors (AZICs) have addressed considerable attention due to their high energy density, low toxicity, and rich abundance of Zn metal. However, the development of ultra‐long cycle life and high energy density AZICs is often hindered by the lack of adequately optimized active carbon (AC) electrodes and compatible electrolytes. Herein, high‐performance, free‐standing AC electrodes for AZICs are derived from sustainable precursors—adenine and D‐ribose—using magnesium chloride hexahydrate as an activation agent via a eutectic template strategy. Furthermore, an aqueous hybrid electrolyte tailored to the designed AC electrodes is developed, significantly enhancing the stability and cycle life of AZICs. The resulting AZIC achieves a high specific capacity of 164.39 F g −1 at 0.1 A g −1 and a magnificently long cell life of over 50 000 cycles with nearly 94.5% capacitance retention at 10 000 th cycles, and 76.3% at 50 000 th cycle. The pouch cell assembly also demonstrates comparable specific capacitance and energy density to the coin cell, underscoring the potential of large‐scale applications of AZICs. }}, author = {{Tao, Li and Li, Chun and Lu, Xuejun and Mir, Rameez Ahmad and Lopez Salas, Nieves and Liu, Jian}}, issn = {{2566-6223}}, journal = {{Batteries & Supercaps}}, number = {{11}}, publisher = {{Wiley}}, title = {{{Adenine and D‐Ribose Coderived Activated Carbon with N‐Methyl‐2‐Pyrrolidone‐Modified Aqueous Electrolyte for Long‐Life Zinc‐Ion Capacitors}}}, doi = {{10.1002/batt.202500161}}, volume = {{8}}, year = {{2025}}, } @article{62653, abstract = {{Enhanced bifunctional electrocatalysis via CuSe2/FeSe2 heterojunctions for efficient water splitting was achieved.}}, author = {{Kumari, Sandhyawasini and Pahra, Swapna and Tripathy, Amrita and Sumanth, N. and Lopez Salas, Nieves and Tiwari, Santosh K. and Khan, Afaq Ahmad and Devi, Pooja and Santosh, M. S.}}, issn = {{2040-3364}}, journal = {{Nanoscale}}, number = {{33}}, pages = {{19253--19265}}, publisher = {{Royal Society of Chemistry (RSC)}}, title = {{{Interfacial engineering of CuSe2/FeSe2 heterojunctions for water splitting: a pathway to high-performance hydrogen and oxygen evolution reactions}}}, doi = {{10.1039/d5nr01393c}}, volume = {{17}}, year = {{2025}}, } @article{62655, abstract = {{Green pea peel (GPP) is a waste, and it is abundant and available to be used for biochar synthesis.}}, author = {{Makinde, Wasiu Olakunle and Hassan, Mohsen A. and Semida, Wael M. and Pan, Ying and Guan, Guoqing and Lopez Salas, Nieves and Khalil, Ahmed S. G.}}, issn = {{2046-2069}}, journal = {{RSC Advances}}, number = {{20}}, pages = {{15819--15831}}, publisher = {{Royal Society of Chemistry (RSC)}}, title = {{{Heteroatom co-doped green pea peel-derived biochar for high-performance energy storage applications}}}, doi = {{10.1039/d5ra01262g}}, volume = {{15}}, year = {{2025}}, } @article{62657, abstract = {{Alkali metal doping is a new and promising approach to enhance the photo/electrocatalytic activity of NiS-based catalyst systems.}}, author = {{Dileepkumar, V. G. and Pahra, Swapna and Lopez Salas, Nieves and Basavaraja, B. M. and Khan, Afaq Ahmad and Sumanth, N. and Devi, Pooja and Santosh, M. S.}}, issn = {{2040-3364}}, journal = {{Nanoscale}}, number = {{5}}, pages = {{2682--2691}}, publisher = {{Royal Society of Chemistry (RSC)}}, title = {{{Enhancing NiS performance: Na-doping for advanced photocatalytic and electrocatalytic applications}}}, doi = {{10.1039/d4nr04293j}}, volume = {{17}}, year = {{2025}}, } @article{62656, author = {{Hu, Jiajun and Goberna-Ferrón, Sara and Simonelli, Laura and Lopez Salas, Nieves and García, Hermenegildo and Albero, Josep}}, issn = {{2574-0962}}, journal = {{ACS Applied Energy Materials}}, number = {{2}}, pages = {{1179--1188}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Fe and Sn Single-Site-Based Electrodes for High-Current CO2 Reduction in Acid Media and Stable Zn–CO2 Batteries}}}, doi = {{10.1021/acsaem.4c02704}}, volume = {{8}}, year = {{2025}}, } @article{62659, abstract = {{The growing rise in agricultural activities has resulted in an increase in unutilized waste which is a significant contributor to greenhouse gas emissions. This has led to a need for sustainable methods to add value to such waste. This work focused on the transformation of agricultural waste into usable products through alkaline treatment to obtain lignin and cellulose, and the evaluation of the derived lignin as a viable carbon precursor in energy storage applications. Laser scribing was used as a fast and simple strategy in producing laser-induced graphene (LIG) electrodes. Lignin was isolated from wheat straw using sodium hydroxide treatment. The pulp from the treatment was subjected to bleaching with sodium chlorite followed by acid hydrolysis to extract microcrystalline cellulose. Fourier-transform infrared spectroscopy (FTIR), Transmission electron microscopy, and Xray diffraction were used for characterization of the materials produced. The fabricated supercapacitor could achieve an areal capacitance (CA) of 5.12 mF/cm2 (0.02 mA/cm2). This study illustrated the successful valorization of wheat straw residue into microcrystalline cellulose and the use of extracted lignin in producing graphitic carbon electrodes for supercapacitors.}}, author = {{Katwesigye, Samuel and El-Khouly, Mohamed E. and Lopez Salas, Nieves and Khalil, Ahmed S.G.}}, issn = {{1662-9752}}, journal = {{Materials Science Forum}}, pages = {{115--120}}, publisher = {{Trans Tech Publications, Ltd.}}, title = {{{Sustainable Development of Graphene Electrodes for Supercapacitors through Laser Scribing of Agrowaste Derived Lignin}}}, doi = {{10.4028/p-fgw0gq}}, volume = {{1152}}, year = {{2025}}, }