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- ItemFirst results of a model user survey on a micro-scale model data standard(2020) Voss, Vivien; Schlünzen, K.Heinke; Grawe, David; Heydebreck, Daniel; Ganske, AnetteMicro-scale models are important to assess processes in complex domains, for example cities. The most common data standard for atmospheric model output data are the CF-conventions, a data standard for netCDF files, but this standard is not adapted to the model output of micro-scale models. As a part of the project AtMoDat (Atmospheric Model Data) we want to develop a model data standard for obstacle resolving models (ORM), including the additional variables (i.e. building structures, wall temperatures) used by these models. In order to involve the micro-scale modeller community in this process, a web based survey was developed and distributed in the modeller community via conferences and email. With this survey we want to find out which micro-scale ORMs are currently in use, their model specifics (e.g. used grid, coordinate system), and the handling of the model result data. Furthermore, the survey provides the opportunity to include suggestions and ideas, what we should consider in the development of the standard. Between September 2019 and July 2020, the survey was accessed 29 times, but only 12 surveys were completed. The finished surveys refer to eight different models and their corresponding model information. Results show that these different models use different output formats and processing tools, which results in different model result handling routines. The participants suggested to use the netCDF data format and to provide information on model initialization, model settings and model input along with the model output data. This would enable an easier intercomparison between different models and repetition of model simulations. Standardized model output and variable names would also enhance the development of shared routines for the analysis of micro-scale model data and a better findability of the data with search engines. This survey will remain open with regular assessments of contents (i.e. November 2020, May 2021; https://uhh.de/orm-survey).
- ItemMaking the Maturity of Data and Metadata Visible with Datacite DOIs(Washington, DC : ESSOAr, 2020) Kaiser, Amandine; Heydebreck, Daniel; Ganske, Anette; Kraft, AngelinaData maturity describes the degree of the formalisation/standardisation of a data object with respect to FAIRness and quality of the (meta-) data. Therefore, a high (meta-) data maturity increases the reusability of data. Moreover, it is an important topic in data management, which is reflected by a growing number of tools and theories trying to measure it, e.g. the FAIR testing tools assessed by RDA(1) or the NOAA maturity matrix(2). If the results of stewardship tasks cannot be shown directly in the metadata, reusers of data cannot easily recognise which data is easy to reuse. For example, the DataCite Metadata Schema does not provide an explicit property to link/store information on data maturity (e.g. FAIRness or quality of data/metadata). The AtMoDat project (3, Atmospheric Model Data) aims to improve the reusability of published atmospheric model data by scientists, the public sector, companies, and other stakeholders. These data are valuable because they form the basis to understand and predict natural events, including the atmospheric circulation and ultimately the atmospheric and planetary energy budget. As most atmospheric data has been published with DataCite DOIs, it is of high importance that the maturity of the datasets can be easily found in the DOI’s Metadata. Published data from other fields of research would also benefit from easily findable maturity information. Therefore, we developed a Maturity Indicator concept and propose to introduce it as a new property in the DataCite Metadata Schema. This indicator is generic and independent of any scientific discipline and data stewardship tool. Hence, it can be used in a variety of research fields. 1 https://doi.org/10.15497/RDA00034 2 Peng et al., 2015: https://doi.org/10.2481/dsj.14-049 3 www.atmodat.de
- ItemTwo-Phase Fluid Flow Experiments Monitored by NMR(Les Ulis : EDP Sciences, 2020) Hiller, Thomas; Hoder, Gabriel; Amann-Hildenbrand, Alexandra; Klitzsch, Norbert; Schleifer, NorbertWe present a newly developed high-pressure nuclear magnetic resonance (NMR) flow cell, which allows for the simultaneous determination of water saturation, effective gas permeability and NMR relaxation time distribution in two-phase fluid flow experiments. We introduce both the experimental setup and the experimental procedure on a tight Rotliegend sandstone sample. The initially fully water saturated sample is systematically drained by a stepwise increase of gas (Nitrogen) inlet pressure and the drainage process is continuously monitored by low field NMR relaxation measurements. After correction of the data for temperature fluctuations, the monitored changes in water saturation proved very accurate. The experimental procedure provides quantitative information about the total water saturation as well as about its distribution within the pore space at defined differential pressure conditions. Furthermore, the relationship between water saturation and relative (or effective) apparent permeability is directly determined. © The Authors, published by EDP Sciences, 2020.
- ItemThe ATMODAT Standard enhances FAIRness of Atmospheric Model data(Washington, DC : ESSOAr, 2020) Heydebreck, Daniel; Kaiser, Amandine; Ganske, Anette; Kraft, Angelina; Schluenzen, Heinke; Voss, VivienWithin the AtMoDat project (Atmospheric Model Data, www.atmodat.de), a standard has been developed which is meant for improving the FAIRness of atmospheric model data published in repositories. Atmospheric model data form the basis to understand and predict natural events, including atmospheric circulation, local air quality patterns, and the planetary energy budget. Such data should be made available for evaluation and reuse by scientists, the public sector, and relevant stakeholders. Atmospheric modeling is ahead of other fields in many regards towards FAIR (Findable, Accessible, Interoperable, Reusable, see e.g. Wilkinson et al. (2016, doi:10.1101/418376)) data: many models write their output directly into netCDF or file formats that can be converted into netCDF. NetCDF is a non-proprietary, binary, and self-describing format, ensuring interoperability and facilitating reusability. Nevertheless, consistent human- and machine-readable standards for discipline-specific metadata are also necessary. While standardisation of file structure and metadata (e.g. the Climate and Forecast Conventions) is well established for some subdomains of the earth system modeling community (e.g. the Coupled Model Intercomparison Project, Juckes et al. (2020, https:doi.org/10.5194/gmd-13-201-2020)), other subdomains are still lacking such standardisation. For example, standardisation is not well advanced for obstacle-resolving atmospheric models (e.g. for urban-scale modeling). The ATMODAT standard, which will be presented here, includes concrete recommendations related to the maturity, publication, and enhanced FAIRness of atmospheric model data. The suggestions include requirements for rich metadata with controlled vocabularies, structured landing pages, file formats (netCDF), and the structure within files. Human- and machine-readable landing pages are a core element of this standard and should hold and present discipline-specific metadata on simulation and variable level.
- ItemOccurrence of Flux Jumps in MgB2 Bulk Magnets during Pulse-Field Magnetization(Bristol : IOP Publ., 2020) Sakai, N.; Oka, T.; Yamanaka, K.; Dadiel, L.; Oki, H.; Ogawa, J.; Fukui, S.; Scheiter, J.; Häßler, W.; Yokoyama, K; Noudem, J.; Miryala, M.; Murakami, M.The magnetic flux capturing of MgB2 bulk magnets made by spark plasma sintering process has been precisely investigated to clarify the mechanism of flux motions during the pulse-field magnetization processes. The field trapping ratio B T/B P was evaluated as a key parameter of field trapping ability which strongly relates to the heat generation due to the rapid flux motion in the samples. The time dependence of magnetic flux density revealed the actual flux motion which penetrated the samples. The trapped fields B T and field trapping ratios B T/B P of various samples were classified into three regions of 'no flux flow', 'fast flux flow' and 'flux jump' according to the generation of heat and its propagation. A flux jump was observed late at 280 ms from the beginning of PFM process, while the field penetration B P showed its peak at 10 ms. Considering the heat propagation speed, the long-delayed flux jump should be attributed to the macroscopic barriers against the heat propagation to the surface centre of bulk magnet. © Published under licence by IOP Publishing Ltd.
- ItemMagnetic Flux Trapping and Flux Jumps in Pulsed Field Magnetizing Processes in REBCO and Mg-B Bulk Magnets(Bristol : IOP Publ., 2020) Oka, T.; Takeda, A.; Oki, H.; Yamanaka, K.; Dadiel, L.; Yokoyama, K.; Häßler, W.; Scheiter, J.; Sakai, N.; Murakami, M.Pulsed-field magnetization technique (PFM) is expected as a cheap and an easy way for HTS bulk materials for utilizing as intense magnets. As the generation of heat due to magnetic flux motion in bulk magnets causes serious degradation of captured fields, it is important to investigate the flux motions during PFM in various field applications. The authors precisely measured the magnetic flux motion in the cryocooled MgB2 bulk magnets containing various amount of Ti. We classified the motions to "no flux flow (NFF)", "fast flux flow (FFF)", and "flux jump (FJ)" regions. The results showed that addition of Ti shifts the field invasion area to high field areas, and expands the NFF regions. The highest field-trapping appears at the upper end of the NFF region. Since the heat generation and its propagation should attribute to the dissipation of magnetic flux, FFF leads to FJ. Compared with MgB2, we referred to GdBCO as for the flux motion. A flux jump was observed at 30 K when the pulse field of 7 T was applied to the preactivated sample, showing its stability against FJ. © Published under licence by IOP Publishing Ltd.
- ItemTowards a reliable bridge joint between REBCO coated conductors(Bristol : IOP Publ., 2020) Kirchner, A.; Nielsch, K.; Hühne, R.REBa2Cu3O7-x (REBCO; RE = Y, Gd) coated conductor wires are commercially available up to a length of about 1 km. However, for large-scale devices like superconducting coils for high-field magnets several kilometres of a coated conductors are required. Therefore, it is desirable to use joints, which exhibit similar superconducting properties as the coated conductor itself. In this study, we jointed commercial REBCO coated conductors by a two-step procedure. At first, a superconducting soldering solution was developed and deposited on unstabilized coated conductors via chemical solution deposition. The soldering precursor is based on a Cu-rich solution with a metal cation ratio Y:Ba:Cu of 1:2:4. Secondly, a piece of the coated conductor was delaminated between the superconducting and the buffer layer and used as bridge between two other conductors covered with the soldering layer. Annealing the resulting bridge joint under pressure results in a mechanical stable configuration. © Published under licence by IOP Publishing Ltd.
- ItemX-Sprint: Climate and Migration - 100% Open Research for Climate Change(Meyrin : CERN, 2020-06-13) Worthington, SimonX-Sprint: Climate and migration - Workshop - Infrastructure for the Year to come Summer School 2020 #OCK @OCKProject - 10 June 2020. From the Open Climate Knowledge project. https://github.com/OCKProject
- ItemA Fair and Comprehensive Comparison of Multimodal Tweet Sentiment Analysis Methods(Ithaka : Cornell University, 2021) Cheema, Gullal S.; Hakimov, Sherzod; Müller-Budack, Eric; Ewerth, RalphOpinion and sentiment analysis is a vital task to characterize subjective information in social media posts. In this paper, we present a comprehensive experimental evaluation and comparison with six state-of-the-art methods, from which we have re-implemented one of them. In addition, we investigate different textual and visual feature embeddings that cover different aspects of the content, as well as the recently introduced multimodal CLIP embeddings. Experimental results are presented for two different publicly available benchmark datasets of tweets and corresponding images. In contrast to the evaluation methodology of previous work, we introduce a reproducible and fair evaluation scheme to make results comparable. Finally, we conduct an error analysis to outline the limitations of the methods and possibilities for the future work.
- ItemDer Publikationsfonds für Open-Access-Monografien Brandenburg - der erste seiner Art auf Bundeslandebene(Zenodo, 2022) Eppelin, Anita; Zeltner, Anja; Falkenburg, PhilippSeit Herbst 2021 steht Angehörigen der acht Hochschulen des Landes Brandenburg ein landesweiter Publikationsfonds für Open-Access-Monografien zur Verfügung. Dieser wird vom Ministerium für Wissenschaft, Forschung und Kultur Brandenburg (MWFK) bereitgestellt, von der Vernetzungs- und Kompetenzstelle Open Access Brandenburg (VuK) koordiniert und gemeinsam mit der AG Publikationsfonds für Open-Access-Monografien Brandenburg weiterentwickelt. Im Poster werden Förderziele und -kriterien sowie der Workflow zwischen Autor:innen, VuK, Bibliotheken und Verlagen dargestellt. Zusätzlich gibt das Poster einen zahlenmäßigen Überblick zur bisherigen Nutzung des Fonds und stellt Herausforderungen und Erfahrungen aus einem Jahr Publikationsfonds-Betrieb dar (Stand Juni 2022). Gestaltung: Nora Ancheva, https://www.togettr.de