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- ItemTemporal Role Annotation for Named Entities(Amsterdam [u.a.] : Elsevier, 2018) Koutraki, Maria; Bakhshandegan-Moghaddam, Farshad; Sack, Harald; Fensel, Anna; de Boer, Victor; Pellegrini, Tassilo; Kiesling, Elmar; Haslhofer, Bernhard; Hollink, Laura; Schindler, AlexanderNatural language understanding tasks are key to extracting structured and semantic information from text. One of the most challenging problems in natural language is ambiguity and resolving such ambiguity based on context including temporal information. This paper, focuses on the task of extracting temporal roles from text, e.g. CEO of an organization or head of a state. A temporal role has a domain, which may resolve to different entities depending on the context and especially on temporal information, e.g. CEO of Microsoft in 2000. We focus on the temporal role extraction, as a precursor for temporal role disambiguation. We propose a structured prediction approach based on Conditional Random Fields (CRF) to annotate temporal roles in text and rely on a rich feature set, which extracts syntactic and semantic information from text. We perform an extensive evaluation of our approach based on two datasets. In the first dataset, we extract nearly 400k instances from Wikipedia through distant supervision, whereas in the second dataset, a manually curated ground-truth consisting of 200 instances is extracted from a sample of The New York Times (NYT) articles. Last, the proposed approach is compared against baselines where significant improvements are shown for both datasets.
- ItemA comprehensive analysis of the history of DFT based on the bibliometric method RPYS(London : BioMed Central, 2019) Haunschild, Robin; Barth, Andreas; French, BernieThis bibliometric study aims at providing a comprehensive analysis of the history of density functional theory (DFT) from a perspective of chemistry by using reference publication year spectroscopy (RPYS). 114,138 publications with their 4,412,152 non-distinct cited references are analyzed. The RPYS analysis revealed three different groups of seminal papers which researchers in DFT have drawn from: (i) some long-known experimental studies from the 19th century about physical and chemical phenomena were referenced rather frequently in contemporary DFT publications. (ii) Fundamental quantum-chemical papers from the time period 1900–1950 which predate DFT form another group of seminal papers. (iii) Finally, various very frequently employed DFT approximations, basis sets, and other techniques (e.g., implicit descriptions of solvents) constitute another group of seminal papers. The earliest cited reference we found was published in 1806. The references to papers published in the 19th century mainly served the purpose of referring to long-known physical and chemical phenomena which were used to test if DFT approximations deliver correct results (e.g., Van der Waals interactions). The foundational papers of DFT by Hohenberg and Kohn as well as Kohn and Sham do not seem to be affected by obliteration by incorporation as they appear as pronounced peaks in our RPYS analysis. Since the 1990s, only very few pronounced peaks occur as most years were referenced nearly equally often. Exceptions are 1993 and 1996 due to seminal papers by Axel Becke, John P. Perdew and co-workers, and Georg Kresse and co-workers.
- ItemRecent developments in the Inorganic Crystal Structure Database: theoretical crystal structure data and related features(Copenhagen : Munksgaard, 2019) Zagorac, D.; Müller, H.; Ruehl, S.; Zagorac, J.; Rehme, S.The Inorganic Crystal Structure Database (ICSD) is the world's largest database of fully evaluated and published crystal structure data, mostly obtained from experimental results. However, the purely experimental approach is no longer the only route to discover new compounds and structures. In the past few decades, numerous computational methods for simulating and predicting structures of inorganic solids have emerged, creating large numbers of theoretical crystal data. In order to take account of these new developments the scope of the ICSD was extended in 2017 to include theoretical structures which are published in peer-reviewed journals. Each theoretical structure has been carefully evaluated, and the resulting CIF has been extended and standardized. Furthermore, a first classification of theoretical data in the ICSD is presented, including additional categories used for comparison of experimental and theoretical information.
- ItemLinked Data Supported Content Analysis for Sociology(Berlin ; Heidelberg : Springer, 2019) Tietz, Tabea; Sack, Harald; Acosta, Maribel; Cudré-Mauroux, Philippe; Maleshkova, Maria; Pellegrini, Tassilo; Sack, Harald; Sure-Vetter, YorkPhilology and hermeneutics as the analysis and interpretation of natural language text in written historical sources are the predecessors of modern content analysis and date back already to antiquity. In empirical social sciences, especially in sociology, content analysis provides valuable insights to social structures and cultural norms of the present and past. With the ever growing amount of text on the web to analyze, also numerous computer-assisted text analysis techniques and tools were developed in sociological research. However, existing methods often go without sufficient standardization. As a consequence, sociological text analysis is lacking transparency, reproducibility and data re-usability. The goal of this paper is to show, how Linked Data principles and Entity Linking techniques can be used to structure, publish and analyze natural language text for sociological research to tackle these shortcomings. This is achieved on the use case of constitutional text documents of the Netherlands from 1884 to 2016 which represent an important contribution to the European cultural heritage. Finally, the generated data is made available and re-usable as Linked Data not only for sociologists, but also for all other researchers in the digital humanities domain interested in the development of constitutions in the Netherlands.
- ItemThesenpapier Nationale Forschungsdateninfrastruktur für die Chemie (NFDI4Chem)(Zenodo, 2018) Koepler, Oliver; Jung, Nicole; Kraft, Angelina; Neumann, Janna; Auer, Sören; Bach, Felix; Bähr, Thomas; Engel, Thomas; Kettner, Carsten; Kowol-Santen, Johanna; Liermann, Johannes; Lipp, Anne; Porzel, Andrea; Razum, Matthias; Schlörer, Niels; Solle, Dörte; Winkler, Torsten“Der stufenweise Aufbau einer Nationalen Forschungsdateninfrastruktur in Netzwerkform hat das Ziel, ein verlässliches und nachhaltiges Dienste-Portfolio zu schaffen, welches generische und fachspezifische Bedarfe des Forschungsdatenmanagements in Deutschland abdeckt.” Für das Fachgebiet Chemie ermöglicht eine solche nationale Forschungsdateninfrastruktur, öffentlich-finanzierte Forschungsdaten effizient zu erheben, standardisiert zu beschreiben, dauerhaft zu speichern und durch Persistent Identifier (PID) eindeutig referenzierbar und auffindbar zu machen. Sie unterstützt gemäß den Vorgaben des RfII die Reproduzierbarkeit und Nachnutzbarkeit der Daten zum Zwecke einer perpetuierten Wissensgenerierung. Mit der Reproduzierbarkeit von Forschungsergebnissen unterstützt eine solche Forschungsdateninfrastruktur den Peer Reviewing Prozess zur Förderung der wissenschaftlichen Selbstkontrolle und erhöht die Datenqualität, insbesondere in wissenschaftlichen Publikationen. Die NFDI4Chem ist ein gemeinschaftlicher Ansatz von Wissenschaftlern aus der Chemie, der Fachgesellschaft Gesellschaft Deutscher Chemiker und deren Fachgruppen, Einrichtungen aus der Forschungsförderung und Infrastruktureinrichtungen (Technische Informationsbibliothek). Eine Gruppe von Vertretern dieser Stakeholder hat sich Ende April 2018 zu einem Auftakttreffen “Fachgespräch NFDI4Chem” in Hannover getroffen. Dieses Papier fasst die Erkenntnisse des Fachgespräches zusammen. Weitere Stakeholder wie Verlage oder Datenbankanbieter sind im folgenden Diskurs willkommen.