Research Data Repository of Saxon Universities
OPARA is the Open Access Repository and Archive for Research Data of Saxon Universities.
Researchers of Saxon Universities can either publish their research data on OPARA, or archive it here to comply with requirements of funding acencies and good scientic practice, without public access.
You can find the documentation of this service at the OPARA manual websites. If you need suppourt using OPARA please contact the Servicedesk of TU Dresden.
Communities in OPARA
Select a community to browse its collections.
Recent Submissions
GRK2802: Production of MgO/TiC Composites From MgO-CRecyclates Using Spark Plasma Sintering
(Technische Universität Bergakademie Freiberg, 2026-10-15) Yu, Jiayan; Schimpf, Christian; Martin, Stefan; Rafaja, David
Using the spark plasma sintering technique, compact MgO/TiC composites were produced from the MgO-C recyclates, which were crushed, sieved, and mixed with titanium powder. The sintering temperatures were 900°C, 1200°C, and 1500°C. The sintering times were 10–30 min. Analysis of the sintered composites using X-ray diffraction unveiled their phase composition and the progress of the TiC1-x formation. Scanning electron microscopy that was complemented by X-ray spectroscopy and electron backscatter diffraction revealed local distribution of individual phases. As TiC1-x is a product of the carbon diffusion into titanium, the sintering temperature and the sintering time play a crucial role in the phase and microstructure formation. Further important factors are the spatial distribution of MgO, graphite, and Ti in the starting powder mixture, because they influence the local availability of graphite as carbon source, and the size of the original Ti grains, which decides about the final concentration gradient of carbon in TiC and about the stoichiometry of this phase, in particular at lower sintering temperatures and/or at shorter sintering times. The presence of impurities stemming from the original MgO-C recyclates is discussed in context of the sintering temperature and sintering time.
GRK 2802: Application of Raman and Photoluminescence Spectroscopy to MgO-C Refractories
(Technische Universität Bergakademie Freiberg, 2026-10-15) Richter, Julia; Drechsler, Felix; Stadtmüller, Till M. J.; Himcinschi, Cameliu; Aneziris, Christos G.; Kortus, Jens
Magnesia-carbon (MgO-C) bricks partially made of recycled magnesia (MgO) are examined in hardened and coked state using Raman and photoluminescence (PL) spectroscopy, focusing on the MgO grains compared with nominally pure MgO powder for reference. Raman and PL signals in the visible to near infrared range are distinguished and interpreted by varying the excitation wavelength between 532, 633, and 785 nm. Besides a broad PL band centered at 565 nm characteristic of the brick-derived MgO, the origin of two sharp high-intensity PL signals (699, 871 nm) surrounded by symmetrical sidebands is clarified. The 699 nm luminescence reveals the presence of trivalent chromium (Cr3+) impurities in the MgO lattice of MgO-C bricks as well as MgO powder, while the latter, V2+-related PL signal is only observed for the brick-derived MgO. The nature of the symmetrical sidebands is investigated by temperature-dependent spectroscopic measurements between 100 and 295 K. The temperature dependence of the intensity ratio between higher energy (anti-Stokes) and lower energy (Stokes) sidebands confirms the phonon involvement in both the MgO:Cr3+ and MgO:V2+ signals. This study enhances the spectroscopic methods to apply to industrial refractory materials, while it reveals impurities on a defect level that is not accessible by any well-established analysis.
Datasets for paper "Discovering Encrypted Client Hello Deployments by Active ECH Probing"
(Technische Universität Dresden, 2026-10-13) Mücke, Jonas; Gasser, Konstantin; Schmidt, Thomas C.; Wählisch, Matthias
This data is supplement to https://doi.org/10.5281/zenodo.22012700 and contains the necessary data to recreate plots and tables of the following paper: Jonas Mücke, Konstantin Gasser, Thomas C. Schmidt, and Matthias Wählisch. 2026. Discovering Encrypted Client Hello Deployments by Active ECH Probing. In Proceedings of the 2026 ACM Internet Measurement Conference (IMC '26). Association for Computing Machinery, New York, NY, USA, 276–286. https://doi.org/10.1145/3777912.3839832
Paper abstract: We present a new measurement method to detect ECH deployments. This method leverages standard-compliant behavior of ECH servers. Prior measurements relied on DNS exposure and reported only one major ECH deployment (Cloudflare). Our measurements reveal yet undiscovered ECH deployments, including a large deployment at Meta. Meta servers support ECH, but ECH configuration is not exposed via the DNS. We also empirically study details such as the level of privacy improvement and latency impact of ECH.
Research data for "Multiscale Characterisation of Lithium Aluminate in Laboratory- and Pilot-Scale EnAM Slags"
(Technische Universität Bergakademie Freiberg, 2026-10-09) Rachmawati, Cindytami; Mongoljiibuu, Shine-Od; Weiss, Joao; Hamers, Maartje; Möckel, Robert; Friedrich, Bernd; Peuker, Urs A.
This dataset supports the study “Applying Engineered Artificial Mineral (EnAM) Concept from Lab to Pilot Scale: Lithium Aluminate in Lithium-Bearing Slag Systems”. It contains experimental and processed data of a 125 kg pilot-scale slag (Slag P).
The data comprise, X-ray diffraction phase analysis, micro-X-ray fluorescence (µXRF) elemental maps, X-ray computed tomography (XCT) volumes, and electron backscatter diffraction (EBSD) measurements. Derived data include segmented EnAM-rich clusters, cluster size and circularity, centroid-based nearest-neighbour distances, three-dimensional anisotropy, and individual lithium aluminate grain properties.
The dataset enables investigation of scale-dependent changes in lithium-bearing phase formation, spatial distribution, clustering and intergrowth. µXRF and XCT data describe EnAM-rich clusters, whereas EBSD data resolve individual crystallographic grains. Documentation identifies sample positions, measurement conditions, processing procedures and the provenance of laboratory-scale comparison data.
Temporal Visuo-Tactile Learning for Dexterous Grasp Stability
(Technische Universität Dresden, 2026-10-08) Nakahara, Ken; Buvailik, Aleksei; Kotov, Prokhor; Calandra, Roberto
This dataset contains 10,000 multimodal robotic grasp trials across 200 everyday objects with diverse shapes, sizes, materials, and compliance, collected for the paper Temporal Visuo-Tactile Learning for Dexterous Grasp Stability. The platform combines a 7-DoF xArm7, a four-fingered, 16-DoF Tilburg Hand with a Digit 360 tactile sensor on each fingertip, and an external RealSense D435i RGB-D camera. Each trial continuously records external RGB-D observations, arm and hand proprioception, tactile images, audio, inertial measurements, pressure, and commanded actions throughout the full grasp attempt, from reaching and hand closure to lifting and post-lift outcome checking. The recordings include phase annotations and binary grasp-stability labels indicating whether the object was successfully lifted and held for three seconds without dropping. Timestamped, asynchronously recorded observations and actions, together with phase start times, allow selected intervals to be resampled into synchronized multimodal sequences; the pre-lift window used in the paper is one such example. The release also provides object reference images, per-object metadata, and Python tools for data visualization and resampling into training-ready samples. These full-grasp recordings support reuse beyond the prediction setting studied in the paper, including action-conditional grasp stability prediction, contact dynamics modeling, and multimodal representation learning for dexterous manipulation.