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See detailSimulation-based Optimisation Of Selective Laser Sintering/Melting Process
Kabore, Brice Wendlassida UL; Peters, Bernhard UL

in Euro PM2019 Congress Proceedings (2019)

In order to adapt Selective Laser Sintering (SLS) and Melting (SLM) to final products and volume production, many scientists have turned to statistical analysis for quality and process stability. Most of ... [more ▼]

In order to adapt Selective Laser Sintering (SLS) and Melting (SLM) to final products and volume production, many scientists have turned to statistical analysis for quality and process stability. Most of which are based on extensive experiments aiming at finding statistical correlations between input parameters such as layer thickness, orientation, scan speed, powder bed temperature, laser power... and resulting strength and residual stress of the manufactured part. However, the rise of computer simulation based on mathematical models allows predictions at a much lower cost. Mathematical modelling of SLS/SLM involves molecular level thermodynamics and thermo-mechanical behaviour of the powder material. In this study, we employ the newly developed Extended Discrete Element Model to reproduce the SLS process including the mechanisms of sintering and the evolution of fracture properties and self-supporting ability. Results show that such microscale model offers high precision and flexibility for finding optimal process parameters. [less ▲]

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See detailIdentification of optimal process parameters in selective laser sintering
Kabore, Brice Wendlassida UL; Estupinan Donoso, Alvaro Antonio UL; Peters, Bernhard UL et al

Scientific Conference (2019)

Selective Laser Sintering (SLS) is an efficient method for manufacturing complex geometries with high strength and durability. The SLS process subjects a powder bed to thermal cycles allowing theparticles ... [more ▼]

Selective Laser Sintering (SLS) is an efficient method for manufacturing complex geometries with high strength and durability. The SLS process subjects a powder bed to thermal cycles allowing theparticles to coalesce into a solid part without being completely melted. The thermal cycles along withthe thermo-mechanical properties of the powder dictate the properties of the manufactured part.Choosing optimal parameters that lead to functional parts with the desired stiffness, density andstrength requires extensive testing. Microscales models such that Molecular dynamics and DiscreteParticles offer great flexibilities and capacity to reproduce the SLS process from the physical point ofview [1].This study presents a multi-physical model based on the Extended Discrete Element Method forsimulating the thermodynamics and thermo-mechanics that take place in the SLS process as well asthe microstructure evolution of the part. A thermo-viscoelastic constitutive model for discreteparticles is coupled with heat transfer, sintering and fracture to predict.A genetic algorithm is employed to identify optimal process parameters, namely laser power,scanning speed, preheating temperature and layer thickness in an automated iterative process. Theseparameters are identified so that the density and strength of the cooled part meet the target values. [less ▲]

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See detailThe Organised Crime-Terrorism Nexus: How to Address the Issue of ISIS Benefitting from Lucrative Criminal Activities?
Ligeti, Katalin UL; Lassalle, Maxime

in Roksandić Vidlička, Sunčana; Engelhart, Marc (Eds.) Dealing with Terrorism. Empirical and Normative Challenges of Fighting the Islamic State (2019)

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See detailLe sens de la lecture
Roelens, Nathalie UL

in La Lecture littéraire dans tous ses étags (2019)

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See detailAutomated Identification of National Implementations of European Union Directives With Multilingual Information Retrieval Based On Semantic Textual Similarity
Nanda, Rohan UL

Doctoral thesis (2019)

The effective transposition of European Union (EU) directives into Member States is important to achieve the policy goals defined in the Treaties and secondary legislation. National Implementing Measures ... [more ▼]

The effective transposition of European Union (EU) directives into Member States is important to achieve the policy goals defined in the Treaties and secondary legislation. National Implementing Measures (NIMs) are the legal texts officially adopted by the Member States to transpose the provisions of an EU directive. The measures undertaken by the Commission to monitor NIMs are time-consuming and expensive, as they resort to manual conformity checking studies and legal analysis. In this thesis, we developed a legal information retrieval system using semantic textual similarity techniques to automatically identify the transposition of EU directives into the national law at a fine-grained provision level. We modeled and developed various text similarity approaches such as lexical, semantic, knowledge-based, embeddings-based and concept-based methods. The text similarity systems utilized both textual features (tokens, N-grams, topic models, word and paragraph embeddings) and semantic knowledge from external knowledge bases (EuroVoc, IATE and Babelfy) to identify transpositions. This thesis work also involved the development of a multilingual corpus of 43 directives and their corresponding NIMs from Ireland (English legislation), Italy (Italian legislation) and Luxembourg (French legislation) to validate the text similarity based information retrieval system. A gold standard mapping (prepared by two legal researchers) between directive articles and NIM provisions was prepared to evaluate the various text similarity models. The results show that the lexical and semantic text similarity techniques were more effective in identifying transpositions as compared to the embeddings-based techniques. We also observed that the unsupervised text similarity techniques had the best performance in case of the Luxembourg Directive-NIM corpus. We also developed a concept recognition system based on conditional random fields (CRFs) to identify concepts in European directives and national legislation. The results indicate that the concept recognitions system improved over the dictionary lookup program by tagging the concepts which were missed by dictionary lookup. The concept recognition system was extended to develop a concept-based text similarity system using word-sense disambiguation and dictionary concepts. The performance of the concept-based text similarity measure was competitive with the best performing text similarity measure. The labeled corpus of 43 directives and their corresponding NIMs was utilized to develop supervised text similarity systems by using machine learning classifiers. We modeled three machine learning classifiers with different textual features to identify transpositions. The results show that support vector machines (SVMs) with term frequency-inverse document frequency (TF-IDF) features had the best overall performance over the multilingual corpus. Among the unsupervised models, the best performance was achieved by TF-IDF Cosine similarity model with macro average F-score of 0.8817, 0.7771 and 0.6997 for the Luxembourg, Italian and Irish corpus respectively. These results demonstrate that the system was able to identify transpositions in different national jurisdictions with a good performance. Thus, it has the potential to be useful as a support tool for legal practitioners and Commission officials involved in the transposition monitoring process. [less ▲]

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See detailGeschlossene Jugendhilfeeinrichtungen. Empirische Ergebnisse aus der Perspektive betroffener Jugendlicher
Lunz, Marei UL

in Österreichisches Jahrbuch für Soziale Arbeit (2019), (7-8), 77-99

In this article, different ways in which young adults process the contexts of secure welfare facilities will be relationally reconstructed by examining the reciprocally interwoven nature of the discourse ... [more ▼]

In this article, different ways in which young adults process the contexts of secure welfare facilities will be relationally reconstructed by examining the reciprocally interwoven nature of the discourse, institutions and individuals via qualitative interviews with the young people concerned. The findings show that young people process their lives in secure institutions through practices of distancing themselves from the discourse, institution and their peers, through retrospective legitimation and through constructing and projecting themselves into an alternative “outside” in contrast to the “inside” of the institution. The insights gained from these findings can be seen as a foundation for further discussion on pedagogical and human rights issues regarding secure institutions. [less ▲]

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See detailGefahr oder Risiko. Zur Geschichte von Kalkül und Einbildungskraft.
Mein, Georg UL; Christians, Heiko

Book published by Fink (2019)

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See detailIntroduction
Giuffrida, Fabio UL; Ligeti, Katalin UL

Report (2019)

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See detailLuxembourg
Ligeti, Katalin UL; Giuffrida, Fabio UL

Report (2019)

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See detailPolicy Recommendations
Ligeti, Katalin UL; Giuffrida, Fabio UL

Report (2019)

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See detailUsing the singular value decomposition to extract 2D correlation functions from scattering patterns
Bender, Philipp Florian UL; Zákutná, Dominika; Disch, Sabrina et al

in Acta Crystallographica. Section A, Foundations and Advances (2019), A75

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See detailSocial division in the market: conspicous consumption with nationalist feelings
Zanaj, Skerdilajda UL

E-print/Working paper (2019)

In this paper, we explore the effects of conspicuous goods as a means of social division between native citizens and migrants. We push forward the hypothesis that choosing a particular good can confer a ... [more ▼]

In this paper, we explore the effects of conspicuous goods as a means of social division between native citizens and migrants. We push forward the hypothesis that choosing a particular good can confer a sense of place. We introduce this idea in an international vertical differentiation market with two variants and two social groups: migrants and natives. Natives are narrow-minded since they attribute a positive social value to the variant that complies with their own consumption culture. Migrants are open-minded. When consumers belonging to different groups meet, they exchange information about their consumption habits and consumption well-being that reveals their consumption culture: narrow-minded versus open-minded. Consequently, after meeting, some consumers may change beliefs (narrow-minded to open-minded or vice versa) and consumption choices. Using a dynamic model, we fully elucidate the steady-state equilibrium and highlight the impact of nationalism on migrant integration. [less ▲]

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See detailConsumption home bias and ethnocentrism: an international duopoly
Zanaj, Skerdilajda UL

E-print/Working paper (2019)

We define a model with two countries and two vertically differentiated goods, a high and a low-quality variant, and heterogenous consumers with respect to their willingness to pay for quality. Consumers ... [more ▼]

We define a model with two countries and two vertically differentiated goods, a high and a low-quality variant, and heterogenous consumers with respect to their willingness to pay for quality. Consumers in one country are ethnocentric in consumption. They thrive additional satisfaction when consuming a domestic good rather than a foreign one since only the former can satisfy their sense of place. We investigate the role of trade costs and ethnocentric attitude in shaping the equilibrium configuration of the international duopoly. [less ▲]

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See detailNon-proteolytic ubiquitination of OTULIN regulates NF-κB signaling pathway
Zhao, Mengmeng; Song, Kun; Hao, Wenzhuo et al

in Journal of Molecular Cell Biology (2019)

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See detailRevealing moment correlations within nanoparticle clusters
Bender, Philipp Florian UL

Scientific Conference (2019)

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See detailAnalyzing moment correlations within clusters of magnetic nanoparticles
Bender, Philipp Florian UL

Scientific Conference (2019)

Detailed reference viewed: 15 (2 UL)
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See detailSimple Conditionals with Constrained Right Weakening
Casini, Giovanni UL; Meyer, Thomas; Varzinczak, Ivan

in Proceedings of the 28th International Joint Conference on Artificial Intelligence (IJCAI 2019) (2019)

In this paper we introduce and investigate a very basic semantics for conditionals that can be used to define a broad class of conditional reasoning systems. We show that it encompasses the most popular ... [more ▼]

In this paper we introduce and investigate a very basic semantics for conditionals that can be used to define a broad class of conditional reasoning systems. We show that it encompasses the most popular kinds of conditional reasoning developed in logic-based KR. It turns out that the semantics we propose is appropriate for a structural analysis of those conditionals that do not satisfy the property of Right Weakening. We show that it can be used for the further development of an analysis of the notion of relevance in conditional reasoning. [less ▲]

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