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266550

Research outputs

As an application-oriented research organisation, Fraunhofer aims to conduct highly innovative and solution-oriented research - for the benefit of society and to strengthen the German and European economy.

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Projects

Fraunhofer is tackling the current challenges facing industry head on. By pooling their expertise and involving industrial partners at an early stage, the Fraunhofer Institutes involved in the projects aim to turn original scientific ideas into marketable products as quickly as possible.

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Researchers

Scientific achievement and practical relevance are not opposites - at Fraunhofer they are mutually dependent. Thanks to the close organisational links between Fraunhofer Institutes and universities, science at Fraunhofer is conducted at an internationally first-class level.

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Institutes

The Fraunhofer-Gesellschaft is the leading organisation for applied research in Europe. Institutes and research facilities work under its umbrella at various locations throughout Germany.

Recent Additions

  • Publication
    Status of the demonstration of the critical technologies of the ATHENA telescope
    ( 2023)
    Ferreira, Ivo
    ;
    Bavdaz, Marcos
    ;
    Ayre, Mark
    ;
    Wille, Eric
    ;
    Brian Shortt
    ;
    Fransen, Sebastiaan
    ;
    Collon, Maximilien
    ;
    Vacanti, Giuseppe
    ;
    Barrière, Nicolas
    ;
    Landgraf, Boris
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    Riekerink, Mark Olde
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    Haneveld, Jeroen
    ;
    Start, Ronald
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    Baren, Coen van
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    Della Monica Ferreira, Desiree
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    Massahi, Sonny
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    Svendsen, Sara
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    Christensen, Finn
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    Krumrey, Michael
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    Skroblin, Dieter
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    Burwitz, Vadim
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    Pareschi, Giovanni
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    Tagliaferri, Gianpiero
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    Salmaso, Bianca
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    Basso, Stefano Maria Massimiliano
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    Moretti, Alberto
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    Spiga, Daniele
    ;
    Valsecchi, Giuseppe
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    Vernani, Dervis
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    Lupton, Paul
    ;
    Mundon, William
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    Gavin Phillips
    ;
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    Korhonen, Tapio
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    Sanchez Becerra, Alejandro
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    Heinis, Dominique
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    Colldelram, Carles
    ;
    Tordi, Massimiliano
    ;
    Willingale, Richard
    The ATHENA (Advanced Telescope for High ENergy Astrophysics) mission is the current 2nd ‘Large’ mission (L2) in the ESA Cosmic Vision programme currently. It is currently at Phase B1 but the mission concept will now enter a reformulation phase that will follow a design-to-cost approach. This paper describes the main technologies behind its reference X-ray telescope based on the modular Silicon Pore Optics (SPO) technology. The large X-ray mirror is the mission enabler being specifically developed for ATHENA, in a joint effort by industry, research institutions and ESA. All aspects of the optics are being addressed, from the mirror plates and their coatings to the mirror modules and their assembly into the ATHENA telescope, as well as the facilities required to build and test the flight optics, demonstrating performance, robustness, and programmatic compliance. An overview of the status of the design and demonstration of the telescope is given. The risks that have successfully been mitigated are made explicit and the remaining risks are identified. Additional presentation content can be accessed on the supplemental content page.
  • Publication
    Plattform für einen sektorenübergreifenden Austausch von Transport- und Energiedaten
    ( 2024)
    Mauch, Lars Andreas
    ;
    Walz, Kathrin
    ;
    ;
    Pfleger, David
    Die Elektrifizierung des straßengebundenen Gütertransports stellt den Logistik- und Energiesektor vor große Herausforderungen. Um Transportunternehmen bedarfsgerecht und zuverlässig mit elektrischer Energie versorgen zu können, müssen Informationen branchenübergreifend verarbeitet werden können. Im mFUND-Forschungsprojekt TruckConnect der Universität Stuttgart wurden die betreffenden Akteure identifiziert und ihre Rollen analysiert sowie eine zentrale Plattform für den erforderlichen Datenaustausch konzipiert.
  • Publication
    Covalent Trapping of Cyclic-Polysulfides in Perfluorinated Vinylene-Linked Frameworks for Designing Lithium-Organosulfide Batteries
    ( 2023)
    Haldar, Sattwick
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    Wäntig, Albrecht
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    Ramuglia, Anthony
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    Bhauriyal, Preeti
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    Khan, Arafat
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    Pastoetter, Dominik
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    Isaacs, Mark
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    De, Ankita
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    Brunner, Eike
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    Wang, Mingchao
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    Weidinger, Inez
    ;
    Feng, Xinliang
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    Heine, Thomas
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    Schneemann, Andreas
    ;
    The strategic combination of redox-active triazine- or quinoxaline-based lithium-ion battery (LIB) mechanisms with the polysulfide ring-mediated lithium-sulfur battery (Li-SB) mechanism enabled the configuration of covalent organic-framework (COF)-derived lithium-organosulfide (Li-OrSB) battery systems. Two vinylene-linked frameworks were designed by enclosing polysulfide rings via postsynthetic framework sulfurization, allowing for the separate construction of triazine-polysulfide and quinoxaline-polysulfide redox couples that can readily interact with Li ions. The inverse vulcanization of the vinylene linking followed by the sulfurization-induced nucleophilic aromatic substitution reaction (SNAr) on the perfluorinated aromatic center of the COFs enabled the covalent trapping of cyclic-polysulfides. The experimentally observed reversible Li-interaction mechanism of these highly conjugated frameworks was computationally verified and supported by in situ Raman studies, demonstrating a significant reduction of polysulfide shuttle in a conventional Li-SB and opening the door for a COF-derived high-performing Li-OrSB.
  • Publication
    Space Sampling Techniques Comparison for a Synthetic Low-Pass Filter Bayesian Neural Network
    ( 2023-12-08)
    Dávalos-Guzmán, Jorge
    ;
    Chavez-Hurtado, Jose L.
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    Brito-Brito, Zabdiel
    ;
    This paper presents a comparative analysis of three sampling techniques for generating space points to develop a Bayesian neural network (BNN) surrogate model of a synthetic second-order low-pass filter. The objective is to assess the effectiveness and efficiency of different sampling methods in the performance of the Bayesian surrogate model. The study draws inspiration from widely used sampling techniques such as uniform distribution, uniformly distributed random numbers, and Latin Hypercube Sampling (LHS). The results reveal that the BNN surrogate model achieves the best performance when using the LHS sampling method highlighting the impact of sampling techniques on the surrogate model's performance.

Most viewed

  • Publication
    Hierarchical Clock Synchronization in MPI
    ( 2018)
    Hunold, S.
    ;
    Carpen-Amarie, A.
    MPI benchmarks are used for analyzing or tuning the performance of MPI libraries. Generally, every MPI library should be adjusted to the given parallel machine, especially on supercomputers. System operators can define which algorithm should be selected for a specific MPI operation, and this decision which algorithm to select is usually made after analyzing bench-mark results. The problem is that the latency of communication operations in MPI is very sensitive to the chosen data acquisition and data processing method. For that reason, depending on how the performance is measured, system operators may end up with a completely different MPI library setup. In the present work, we focus on the problem of precisely measuring the latency of collective operations, in particular, for small payloads, where external experimental factors play a significant role. We present a novel clock synchronization algorithm, which exploits the hierarchical architecture of compute clusters, and we show that it outperforms previous approaches, both in run-time and in precision. We also propose a different scheme to obtain precise MPI run-time measurements (called Round-Time), which is based on given, fixed time slices, as opposed to the traditional way of measuring for a predefined number of repetitions. We also highlight that the use of MPI_Barrier has a significant effect on experimentally determined latency values of MPI collectives. We argue that MPI_Barrier should be avoided if the average run-time of the barrier function is in the same order of magnitude as the run-time of the MPI function to be measured.
  • Publication
    Characterization of self-cleaning properties on superhydrophobic aluminum surfaces fabricated by direct laser writing and direct laser interference patterning
    ( 2020)
    Milles, Stephan
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    Soldera, Marcos
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    ;
    Self-cleaning ability on technical surfaces can increase the added value of a product. A common path to achieve this property is making the surface superhydrophobic so that water droplets can roll down, picking up dirt particles. In this contribution, the self-cleaning efficiency of Al surfaces structured with direct laser writing (DLW), direct laser interference patterning (DLIP) and a combination of both technologies was quantitatively determined. This was performed by developing a characterization method, where the treated samples are firstly covered with either MnO2 or polyamide micro-particles, then tilted by 15° and 30° and finally washed applying up to nine water droplets (10 µl) over the contaminated surfaces. Then, an optical analysis by image processing of the remaining contamination particles on the textured surfaces was realized after each droplet rolled over the surface. The DLIP textures showed the best performance, allowing the removal of more than 90% of the particles after just three droplets were released. High-speed videos and scanning electron microscopy characterization allowed a deeper understanding on the cleaning behavior and on the relationship between surface microstructure and particle size and shape.