The Reeb Graph Edit Distance Is Universal

We consider the setting of Reeb graphs of piecewise linear functions and study distances between them that are stable, meaning that functions which are similar in the supremum norm ought to have similar Reeb graphs. We define an edit distance for Reeb graphs and prove that it is stable and universal, meaning that it provides an upper bound to any other stable distance. In contrast, via a specific construction, we show that the interleaving distance and the functional distortion distance on Reeb graphs are not universal

An edit distance for Reeb graphs

We consider the problem of assessing the similarity of 3D shapes using Reeb graphs from the standpoint of robustness under perturbations. For this purpose, 3D objects are viewed as spaces endowed with real-valued functions, while the similarity between the resulting Reeb graphs is addressed through a graph edit distance. The cases of smooth functions on manifolds and piecewise linear functions on polyhedra stand out as the most interesting ones. The main contribution of this paper is the introduction of a general edit distance suitable for comparing Reeb graphs in these settings. This edit distance promises to be useful for applications in 3D object retrieval because of its stability properties in the presence of noise

Concreteness, context-availability, and image-ability ratings and word associations for abstract, concrete, and emotion words.

Normative values on various word characteristics were obtained for abstract, concrete, and emotion words in order to facilitate research on concreteness effects and on the similarities and differences among the three word types. A sample of 78 participants rated abstract, concrete, and emotion words on concreteness, context availability,and imagery scales, Word associations were also gathered for abstract, concrete, and emotion words. The data were used to investigate similarities and differences among these three word types on word attributes, association strengths, and number of associations. These normative data can be used to further research on concreteness effects, word type effects, and word recognition for abstract, concrete, and emotion words

Challenges in the Automatic Analysis of Students' Diagnostic Reasoning

Diagnostic reasoning is a key component of many professions. To improve students' diagnostic reasoning skills, educational psychologists analyse and give feedback on epistemic activities used by these students while diagnosing, in particular, hypothesis generation, evidence generation, evidence evaluation, and drawing conclusions. However, this manual analysis is highly time-consuming. We aim to enable the large-scale adoption of diagnostic reasoning analysis and feedback by automating the epistemic activity identification. We create the first corpus for this task, comprising diagnostic reasoning self-explanations of students from two domains annotated with epistemic activities. Based on insights from the corpus creation and the task's characteristics, we discuss three challenges for the automatic identification of epistemic activities using AI methods: the correct identification of epistemic activity spans, the reliable distinction of similar epistemic activities, and the detection of overlapping epistemic activities. We propose a separate performance metric for each challenge and thus provide an evaluation framework for future research. Indeed, our evaluation of various state-of-the-art recurrent neural network architectures reveals that current techniques fail to address some of these challenges

Intensive Süßstoffe in Bezug auf Tumorentstehung

Süßstoffe sind natürliche oder synthetisch hergestellte, nahezu energiefreie Ersatzstoffe für Zucker. Durch ihre viel höhere Süßkraft, verglichen mit Saccharose, werden nur Mengen im Milligrammbereich benötigt. Andere Vorteile sind, dass sie nicht oder nur wenige Kalorien besitzen und keinen Karies verursachen, da sie von der Mundflora nicht metabolisiert werden. Einsatz finden sie vor allem bei der Herstellung diätetischer Produkte, wie z.B. Getränke, Süßwaren oder Dessertspeisen. Seit der Zulassung der einzelnen Süßstoffe, wird ihre gesundheitliche Unbedenklichkeit immer wieder in Frage gestellt und aufs Neue untersucht. Im ersten, theoretischen Teil werden die einzelnen Süßstoffe näher erläutert Im Anschluss daran werden die diversen experimentellen Tierversuche und epidemiologischen Studien von mir zusammengefasst und beurteilt. Es konnten einige positive Ergebnisse aufgezeigt werden, die jedoch durch beispielsweise die falsche Versuchsmethode, diverse Störfaktoren und der Verwendung von falschen Versuchstieren, als ungültig betrachtet wurden. Zusammenfassend kann gesagt werden, dass nach derzeitigem Wissensstand keiner der in der Arbeit erwähnten Süßstoffe, eine kanzerogene Wirkung beim Menschen ausüb

Sozialer Kompetenzerwerb bei Menschen mit Autismus im Freizeitbereich

Das Ziel dieser Arbeit liegt darin herauszufinden, inwiefern Menschen mit Autismus in einem Freizeitclub speziell für diese Personengruppe soziale Kompetenzen erlernen können. Diese Arbeit befasst sich im theoretischen Teil mit den Definitionen von Behinderung, von informellem Lernen, von sozialer Kompetenz und Freizeit im Hinblick auf den Erwerb von sozialen Kompetenzen im Freizeitbereich. Inwiefern im Freizeitbereich informelles Lernen eine Rolle spielt, wird in dieser Diplomarbeit erarbeitet. Desweiteren wird auf das Phänomen Autismus näher eingegangen um zu verdeutlichen, welche Schwierigkeiten Menschen mit Autismus im sozialen Miteinander haben. Aufbauend auf dem theoretischen Teil wird im empirischen Teil genauer auf das Ziel der Forschung, die Ausführung und die Ergebnisse derselben eingegangen. Die Daten wurden aus Beobachtungen und Interviews herausgefiltert und nach der Grounded Theory mit Hilfe des Computerprogramms Atlas.ti bearbeitet. Aus den Informationen wurde eine Theorie erarbeitet, die auf den erhobenen Daten basiert.This thesis aims at discovering if social competence can be learned by autistic individuals through visiting a specifically designed leisure club. The thesis’ theoretical part extensively deals with the definitions of disabilities, informal learning and social competence in the context of acquiring social competence during leisure time. The importance and role of informal learning during leisure time is explained. Furthermore, the phenomenon of autism is discussed in detail to better show the difficulties autistic individuals have to face in social relations. Based heavily on the theoretical part, the thesis’ empirical part concentrates on the goals of the research, its carrying into execution and its outcome. The empirical data was collected through observations and interviews and was processed following the “Grounded Theory” using the “Atlas.ti” computer program. A theory based on the collected data was constructed using the mentioned information

Application of virtual anthropology methods to fossil human dental remains

The application of virtual anthropology methods to fossil human dental remains has gained more and more attention in the past years. Here we present studies on internal and external dental tissues of different tooth classes (including deciduous teeth) to distinguish between modern humans and Neanderthals. This may be of particular importance when it comes to fossil remains dating to the transition of the middle palaeolithic to the upper palaeolithic

Modificação de partículas inorgânicas com compostos organo fosforados para a aplicação como aditivos retardantes de chama em sistemas poliméricos.

Este trabalho tem como objetivos modificar partículas de argilas hidrotalcita e montmorilonita e partículas de sílica gel com compostos organo fosforados, caracterizá-las e ainda testar a resistência à chama de nanocompósitos de matriz de EVA obtidos com 15% em massa dessas partículas. A caracterização das partículas modificadas foi realizada através de análises de Microscopia Eletrônica de Transmissão (MET), Ressonância Magnética Nuclear de sólidos RMN-P 31, Difração de Raio-X (DRX), Espectroscopia vibracional de absorção no Infravermelho e Termogravimetria (TGA), enquanto os compósitos de EVA foram processados em câmara de mistura e avaliados via Teste de Chama horizontal UL-94 e Microscopia Eletrônica de Varredura (MEV-EDS). As modificações realizadas na sílica gel causaram uma drástica diminuição no tamanho dos aglomerados de sílica. A presença de fosfatos e fosfinatos nas partículas inorgânicas modificadas foi confirmada através de análises de RMN-P 31 e de FTIR. As percentagens de massa residual obtidas nos termogramas confirmaram o mecanismo anti-chama em fase condensada do fosfato e em fase gás do fosfinato. A maioria dos compósitos apresentou resistência à chama de classificação HB sendo que o sistema de sílica com difenil fosfinato foi o mais eficaz no combate à chama do EVA. Visto que, comercialmente, os polímeros recebem uma grande quantidade de aditivos anti-chama (30 a 60%), o uso de 15% de aditivos nos compósitos deste trabalho indica que os resultados obtidos até então são no mínimo promissores.The purpose of this work is to modify hydrotalcite and montmorillonite clays and silica gel particles with organo phosphorous compounds, characterize them and also test the flame resistance of nanocomposites of EVA obtained with 15% wt of these particles. The characterization of the modified particles was performed by analysis of transmission electron microscopy (TEM), Nuclear Magnetic Resonance at Solid state P31 -NMR, X-Ray Diffraction (XRD), Infrared Spectroscopy and Thermogravimetry (TGA), while EVA composites were processed in the mixing chamber and were evaluated by Test for Flammability UL-94 and Scanning Electron Microscopy (SEM-EDS). The changes made in the silica gel caused a drastic decrease in the size of silica clusters. The presence of phosphates and phosphinates in the modified inorganic particles was confirmed by P31 -NMR analysis and infrared spectroscopy. The percentages of residual mass in thermograms confirmed the condensed phase flame retardant mechanism of phosphate and gas phase mechanism of phosphinate. Most composites showed the HB classification of flame resistance and the system silica with diphenyl phosphinate was the most effective in combating EVA flame. Since, polymers usually receive a large quantity of anti-flame additives (30 to 60%), the use of 15% wt of additives in the composites of this study indicate that the results are promisin