335598 research outputs found
Sort by
Automated extraction of comprehensive digital twin models for smart manufacturing systems
No full textManufacturing systems involve multiple, often conflicting, objectives referred to as performance indicators,
including production efficiency, resource utilization, energy consumption, carbon emissions, and waste reduc-
tion, which correspond to different dimensions of the system, such as time, energy consumption, and waste
generation aspects. Digital Twins have emerged as a powerful tool, integrating data-driven simulation and
analysis of complex systems, such as manufacturing systems. Process Mining (PM), along with data analysis,
enables the automatic discovery of executable discrete-event simulation models directly from production event
logs. These data-driven models are the key to enabling near-real-time Digital Twins of discrete-event systems.
Stochastic Petri Nets (SPNs) offer a robust and intuitive modeling formalism well-suited for representing the
extracted models derived from PM, particularly in the context of manufacturing systems. However, standard
SPNs face challenges in incorporating dimensions beyond time, such as energy consumption and waste gener-
ation. This limitation often results in suboptimal decision-making and reduced system efficiency. In this paper,
we propose a Comprehensive Digital Twin (CDT) framework that employs Multi-Flow Process Mining (MFPM) to
automatically extract Multidimensional Stochastic Petri Nets (MDSPNs) as underlying models of manufacturing
systems. To support the modeling and simulation of extracted MDSPNs, we introduce and utilize our tool,
MDPySPN. The CDT framework supports multi-objective decision-making for various performance indicators of
the system. Through an illustrative case study of hot forging process chains, we showcase the development of
CDT for time, energy consumption, and waste generation dimensions. We further illustrate the utilization of CDT
to analyze and support decision-making to enhance the case study system according to its objectives
Assessment of Digital Tools for Climate Change Mitigation in the Built Environment: Early Insights from IEA EBC Annex 89
No full textIn light of the urgent need for climate change mitigation in the construction and real estate sectors, it is crucial to implement effective measures that will drive meaningful progress. Digital tools that support the assessment of buildings’ whole-life carbon emissions play a key role in this effort. However, the successful implementation of these tools relies on their effective and efficient use by various stakeholder groups, each of which has different decision-making needs and workflows. Notably, integrating diverse perspectives into tool quality and service, particularly those of users and developers, remains an under-explored area. This study presents key findings from an international survey conducted across participating countries as part of the IEA EBC Annex 89 project, which focuses on implementing net-zero whole-life carbon buildings. The survey, which is part of a broader set of Annex activities, maps existing tools and analyses aspects such as their capabilities (e.g. the environmental indicators assessed by the tool), information management (e.g. databases) and practical integration (e.g. the format of the data output). This paper presents the survey methodology and focuses on analysing a subset of the results in order to evaluate whether current tools meet the needs of stakeholders and address the challenges of integrating them into design and decision-making processes
Co-Simulation eines hydraulischen Ersatzuntergrunds zur wirkungsäquivalenten Abbildung mineralischer Materialien = Co-simulation of a Hydraulic Substitute Base for the Effect-equivalent Modelling of Mineral Materials
No full textThis paper presents a co-simulation consisting of an FEM (finite element method) and a hydraulic model. The co-simulation can be used to determine the setting parameters for a hydraulic substitute base in order to replicate the behaviour of different types of mineral material. The substitute base, which consists of hydraulic components, enables repeatable measurements on rotary hammers. Previous simulation models for rotary hammers based on impact laws and spring-damper models are not suitable for the development of a hydraulic substitute base, as they do not take into account the influence of the geometry of the impact bodies or cannot be transferred to other bases. With Co-Simulation, the FEM model allows the impact mechanics of a rotary hammer to be simulated, considering the impact body geometry, while the hydraulic model can be used to simulate the damping characteristics of the substitute base
„Eingeschlossenes Wasser verstärkt die Bindung gelöster Moleküle.“ – Forschende am Karlsruher Institut für Technologie entscheiden langjährigen Streit über die Wirkungen von Wasser auf der molekularen Ebene - Campus-Report am 20.01.2026
No full textAuf der molekularen Ebene ist vieles anders als in der Makrowelt, in der wir im Alltag leben. So zeigt auch Wasser in lebenden Zellen überraschende Effekte. Seit langem streiten sich Chemiker darüber, wie Wasser die Bindung darin gelöster Moleküle beeinflusst. Verhalten Wassermoleküle sich als neutrales Medium? Oder verstärken sie nicht vielmehr die Bindekräfte der darin gelösten Moleküle? Forschenden des Karlsruher Instituts für Technologie ist es jetzt in Zusammenarbeit mit einer Arbeitsgruppe an der Constructor University in Bremen gelungen, diese nicht nur für die Biochemie wichtige Grundsatzfrage zu entscheiden. Durch die Simulation molekularer Vorgänge in standardisierten Lösungen konnten sie zeigen, dass die Zellbindung einer in Wasser gelösten Wirksubstanz durch den hydrophoben, d.h. den wasserabweisenden Effekt aktiv verstärkt wird. Das Ergebnis einer bahnbrechenden Grundlagenforschung, die neue Wege für die Entwicklung von Medikamenten und Sensoren eröffnet
Inverse Electromagnetic Scattering Problems for Long Tubular Objects
No full textWe consider the inverse time-harmonic electromagnetic scattering problem of reconstructing an object from knowledge of the generated far-field pattern for one incident field in the case of a long tubular object. Both perfectly conducting and penetrable objects are considered. The inverse scattering problem can be formulated as a nonlinear, ill-posed operator equation where the operator is the far-field map that maps the boundary of the scatterer to the far-field pattern of the scattered field. The shape of the scatterer is reconstructed using a Gauss–Newton minimization procedure for the regularized relative residual of this equation. Our main theoretical result is a characterization of the domain derivative of the far-field map for the class of tubular objects considered. Numerical examples are provided in which the computation of the electromagnetic scattered fields and their domain derivatives is carried out using boundary element methods. Even for noisy data, we obtain very accurate reconstructions of scatterers with rather complicated shapes
Trust in Prosthetics: From the Early Nanoethics Discussions to Current Discourse on Neurotechnologies
No full text
Single crystal growth, structural and physical properties, and absence of a charge density wave in Ti ₀.₈₅ Fe₆ Ge₆
No full textKagome materials with charge density waves (CDWs) are fascinating quantum systems, offering an ideal platform to explore intertwined orders and to uncover novel mechanisms behind CDW formation. Chemical models have been developed and applied to predict CDW in -type kagome materials, such as the rattling chain model based on ScVSn and the magnetic energy-saving model based on FeGe. In this study, we successfully synthesized TiFeGe single crystals using the vapor transport method. As predicted by the rattling chain model, these crystals are expected to exhibit kagome CDW behavior. Magnetization measurements indicate that TiFeGe is an easy-axis antiferromagnet with = 488 K, and transport measurements reveal metallic behavior primarily driven by electron-type carriers. However, no clear signatures of a CDW were observed in TiFeGe. Density functional theory calculations demonstrate a markedly distinct electronic structure compared to related compounds: instead of a carrier-doping-induced rigid shift, the density of states shifted away from the Fermi level. Consistent with our structural investigations, the absence of a CDW and the unusual band structure can be attributed to the bonding characteristic within TiFeGe. The strong covalent bonds of Ti-Ge1b, along with the solid Ge1b-Ge1b dimers, prevent the Ti-Ge1b-Ge1b-Ti chain from rattling. The presence of an Fe-Fe antibonding state at the Fermi level enhances the spin polarization and depletes the electronic density around the Fermi level. Our results suggest that both the ionic radius and the bonding characteristics of the filler atom are crucial for the formation of CDWs in kagome materials. These factors can serve as supplementary terms to the rattling chain model, providing new insights for the discovery of novel kagome CDW materials
@kit-data-manager/react-search-component v0.4.0
No full textAll-in-one component for rendering an elastic search UI for searching anything. Includes an interactive graph of related records and unique identifier resolving