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See detailDemountable and reusable construction system for steel-concrete composite structures
Odenbreit, Christoph UL; Kozma, Andras UL

in Odenbreit, Christoph; Kozma, Andras (Eds.) Demountable and reusable construction system for steel-concrete composite structures (2020, October 30)

In the face of climate change and the depletion of finite resources, sustainability is becoming increasingly important recently. This is especially true in the construction industry that is responsible ... [more ▼]

In the face of climate change and the depletion of finite resources, sustainability is becoming increasingly important recently. This is especially true in the construction industry that is responsible for the 11% of global carbon dioxide emissions. Besides the technological improvements, the emissions can be further reduced by the application of the principles of the circular economy. This concept is based on the efficient allocation of resources. Three terms are frequently used when talking about this concept: reduce, reuse and recycle. Reducing is cut-ting back on the amount of waste we produce, reusing is finding a new way to use our products so that they do not be-come waste, and recycling is using the materials of our products to produce new materials. The traditional life-cycle of a building usually follows a linear model from the extraction of the raw materials through material production, component manufacturing, construction and building use, until when finally the building is demolished and most of the materials become debris and go into landfill. This is in direct opposition with the concept of circular economy. With proper considerations at the design stage, it is possible to deconstruct whole buildings and re-erect them elsewhere. In the frame of the RFCS Research Project “REDUCE” of the European Commission, a demountable and reusable construction system for steel-concrete composite structures has been recently developed. The system is based on a modular “kit-of-parts” system that uses prefabricated and standardised elements that are easy to manufacture and to assemble with the help of standardised connections. The elements were designed in a systematic way such that, a wide variety of different configurations are possible. In this system, the geometry of all elements respects the planning grid that is based on a basic module size. The research included the development and structural testing of novel demountable and adjustable structural solutions including beam-to-slab, beam-to-beam and beam-to-column connections. During the development of the structural solutions the following aspects were considered: structural performance, safety, installation and tolerances, demountability, corrosion resistance, aesthetics, economy, adaptability, standardisation and environmental impact. The laboratory testing was supplemented by nonlinear numerical studies using the finite element software ABAQUS. Based on the results and the experiences obtained throughout the research project, a design proposal was prepared. One objective of the project was to find structural solutions that are easily applicable and compatible with the current standard de-sign rules. The proposed beam-to-beam and beam-to-column joint is in the scope of EN1993-1-8. The new shear connections behave differently than the traditionally applied welded studs. The cor-responding standard would not allow the equidistant placement of the connectors nor the application of the partial shear theory. This would make the use of demountable shear connections complicated and uneconomical. In order to overcome this issue, a simple algorithm was developed that transforms the elastic-brittle shear connection behaviour into an equivalent ductile rigid-plastic behaviour so that the Eurocode 4 design rules for the determination of the moment resistance of composite beams with partial shear connection remain applicable. The design proposal also contains recommendations to maximize the reuse potential of the building components. This paper presents a general overview of the developed construction system and the corresponding laboratory tests and numerical studies as well as recommendations for the design and application of de-mountable and reusable composite structures. [less ▲]

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See detailChanges in Neighborhood-Level Concentrated Disadvantage and Social Networks Among Older Americans
Settels, Jason UL

in Journal of Applied Gerontology (2020)

Close social networks provide older persons with resources, including social support, that maintain their well-being. While scholarship shows how networks change over time, a dearth of research ... [more ▼]

Close social networks provide older persons with resources, including social support, that maintain their well-being. While scholarship shows how networks change over time, a dearth of research investigates changing social contexts as causes of network dynamics. Using the first two waves of the National Social Life, Health, and Aging Project survey (N = 1,776), this study shows how rising neighborhood-level concentrated disadvantage through the Great Recession of 2007–2009 was associated with smaller close networks, largely due to fewer new close ties gained, among older Americans. Worsening neighborhood circumstances pose obstacles to older residents’ acquisition of new close ties, including heightened fear, lower generalized trust, stress and depression, and declines in local institutions that attract both residents and nonresidents. [less ▲]

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See detailThe patients’ perspective on access to and use of Personal Health Records
Paccoud, Ivana UL; Baumann, Michèle UL; Le Bihan, Etienne UL et al

Scientific Conference (2020, October 29)

We present the patients' perspective regarding the use of Personal Health Records, and give insights on patients' characteristics, such as socioeconomic and behavioural factors, that are associated with ... [more ▼]

We present the patients' perspective regarding the use of Personal Health Records, and give insights on patients' characteristics, such as socioeconomic and behavioural factors, that are associated with the access to and use of Personal Health Records. The findings come from the INTERREG APPS project that investigated preferences for and intention to use Personal Health Records in four cross-border regions, in Lorraine/France, Luxembourg, Rhineland-Palatinate and Saarland/Germany, and Wallonia/Belgium. [less ▲]

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See detailOptimised biomolecular extraction for metagenomic analysis of microbial biofilms from high-mountain streams
Busi, Susheel Bhanu UL; Pramateftaki, Paraskevi; Brandani, Jade et al

in PeerJ (2020)

Glacier-fed streams (GFS) are harsh ecosystems dominated by microbial life organized in benthic biofilms, yet the biodiversity and ecosystem functions provided by these communities remain under ... [more ▼]

Glacier-fed streams (GFS) are harsh ecosystems dominated by microbial life organized in benthic biofilms, yet the biodiversity and ecosystem functions provided by these communities remain under-appreciated. To better understand the microbial processes and communities contributing to GFS ecosystems, it is necessary to leverage high throughput sequencing. Low biomass and high inorganic particle load in GFS sediment samples may affect nucleic acid extraction efficiency using extraction methods tailored to other extreme environments such as deep-sea sediments. Here, we benchmarked the utility and efficacy of four extraction protocols, including an up-scaled phenol-chloroform protocol. We found that established protocols for comparable sample types consistently failed to yield sufficient high-quality DNA, delineating the extreme character of GFS. The methods differed in the success of downstream applications such as library preparation and sequencing. An adapted phenol-chloroform-based extraction method resulted in higher yields and better recovered the expected taxonomic profile and abundance of reconstructed genomes when compared to commercially-available methods. Affordable and straight-forward, this method consistently recapitulated the abundance and genomes of a mock community, including eukaryotes. Moreover, by increasing the amount of input sediment, the protocol is readily adjustable to the microbial load of the processed samples without compromising protocol efficiency. Our study provides a first systematic and extensive analysis of the different options for extraction of nucleic acids from glacier-fed streams for high-throughput sequencing applications, which may be applied to other extreme environments. [less ▲]

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See detailHomomorphic encryption and multilinear maps based on the approximate-GCD problem
Lima Pereira, Hilder Vitor UL

Doctoral thesis (2020)

Cryptographic schemes are constructed on top of problems that are believed to be hard. In particular, recent advanced schemes, as homomorphic primitives and obfuscators, use the approximate greatest ... [more ▼]

Cryptographic schemes are constructed on top of problems that are believed to be hard. In particular, recent advanced schemes, as homomorphic primitives and obfuscators, use the approximate greatest common divisor (AGCD) problem, which is simple to describe and easy to implement, since it does not require complex algebraic structures nor hard-to-sample probability distributions. However, in spite of its simplicity, the AGCD problem generally yields inefficient schemes, usually with large ciphertext expansion. In this thesis, we analyze the AGCD problem and several existing variants thereof and propose a new attack on the multi-prime AGCD problem. Then, we propose two new variants: 1. The vector AGCD problem (VAGCD), in which AGCD instances are represented as vectors and randomized with a secret random matrix; 2. The polynomial randomized AGCD problem (RAGCD), that consists of representing AGCD samples as polynomials and randomizing them with a secret random polynomial. We show that these new variants cannot be easier than the original AGCD problem and that all the known attacks, when adapted to the VAGCD and the RAGCD problem, are more expensive both in terms of time and of memory, allowing us then to chose smaller parameters and to improve the efficiency of the schemes using the AGCD as the underlying problem. Thus, by combining techniques from multilinear maps and indistinguishability obfuscation with the VAGCD problem, we provide the first implementation of a N-party non-interactive key exchange resistant against all known attacks. Still aiming to show that the VAGCD problem can lead to performance improvements in cryptographic primitives, we use it to construct a homomorphic encryption scheme that can natively and efficiently operate with vectors and matrices. For instance, for 100 bits of security, we can perform a sequence of 128 homomorphic products between 128-dimensional vectors and 128x128 matrices in less than one second. We also use our scheme in two applications: homomorphic evaluation of nondeterministic finite automata and a Naïve Bayes classifier. Finally, using the RAGCD problem, we construct a new homomorphic scheme for polynomials and we propose new fast bootstrapping procedures for fully homomorphic scheme (FHE) over the integers. Therewith, we can for the first time bootstrap AGCD-based FHE schemes in less than one second in a common personal computer. For the best of our knowledge, only FHE schemes based on the LWE problem had subsecond bootstrapping procedures, while AGCD-based schemes required several seconds or even minutes to be bootstrapped. [less ▲]

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See detailDigital Detective Work: Connecting Cheminformatics, Mass Spectrometry and our Environment (analytica Conference)
Schymanski, Emma UL; Bolton, Evan

Scientific Conference (2020, October 20)

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See detailData Science and Environmental Cheminformatics (SanDAL Workshop, Uni Lu)
Schymanski, Emma UL

Presentation (2020, October 13)

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See detailCollaboration with parents and multiliteracy in early childhood education
Kirsch, Claudine UL; Neumann, Sascha; Aleksic, Gabrijela UL et al

Scientific Conference (2020, October 09)

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See detailDiscursive Input/Output Logic: Deontic Modals, and Computation
Farjami, Ali UL

Doctoral thesis (2020)

Detailed reference viewed: 66 (2 UL)
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See detailOrienter les soins vers le patient partenaire. Un livre blanc pour la Grande Région
Pétré Benoit, Consortium APPS Lux; Baumann, Michèle UL; Chauvel, Louis UL et al

Book published by INTERREG APPS (2020)

Les différents chapitres de ce livre proposent une approche holistique pour faire évoluer le système de santé vers le partenariat de soins. Résultat de trois années de recherche et de concertation, le ... [more ▼]

Les différents chapitres de ce livre proposent une approche holistique pour faire évoluer le système de santé vers le partenariat de soins. Résultat de trois années de recherche et de concertation, le Livre Blanc s’appuie sur des recherches documentaires (analyse de la littérature scientifique et de la législation spécifique de chaque pays), des entretiens et des enquêtes auprès de nombreux acteurs, le repérage et l’analyse d’initiatives en GR et la discussion orientée vers le consensus. Par ailleurs, les propositions de recommandations ont été élaborées et discutées lors d’un séminaire interrégional réalisé en décembre 2019. Le Livre Blanc est structuré en 5 parties qui s’adressent chacune à un public ciblé. La première partie situe le contexte dans lequel s’est réalisé le projet et décrit la méthodologie du programme. La seconde partie est consacrée aux aspects réglementaires de l’approche patient partenaire et à leurs conséquences sur les pratiques et les initiatives analysées sur le terrain. Elle est destinée de manière privilégiée aux mandataires politiques. La troisième partie propose une réflexion sur le développement de stratégies de partenariat au niveau des institutions de santé. Elle concerne les gestionnaires des établissements de santé. La quatrième partie vise à amener les professionnels à s’interroger sur ce que le partenariat de soins peut leur apporter dans leurs pratiques de soins. Elle s’adresse, en particulier, aux acteurs en contact direct avec les patients. La cinquième et dernière partie suggère différentes voies possibles de développement de l’APPS dans les domaines de l’enseignement et de la recherche. Toutes ces parties s’adressent bien évidemment au patient, qui est au coeur de l’APPS. Les prises de position proposées par ce Livre Blanc s’appuient sur les données collectées par le consortium de recherche de 2017 à 2020. Dès lors, ce document ne peut être exhaustif et est appelé à évoluer, basé davantage sur une fonction vectrice de normes que de règles. Pour davantage d’information et pour connaitre nos activités et nos publications, rendezvous sur le site web du projet APPS (https://www.patientpartner.org/). [less ▲]

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See detailGuide historique et architectural Esch-sur-Alzette
Scuto, Denis UL; Lorang, Antoinette; Reuter, Antoinette et al

Book published by C2DH & capybarabooks (2020)

Detailed reference viewed: 61 (0 UL)
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See detailFractional Linear Prediction Toolbox for MATLAB
Despotovic, Vladimir UL; Skovranek, Tomas

in Proc. of 21th International Carpathian Control Conference (ICCC) (2020, October)

This paper presents the Fractional Linear Prediction (FLP) Toolbox implemented in MATLAB with a supporting livescript interface that offers an user-friendly environment for the prediction of one ... [more ▼]

This paper presents the Fractional Linear Prediction (FLP) Toolbox implemented in MATLAB with a supporting livescript interface that offers an user-friendly environment for the prediction of one-dimensional signals. Two versions of the FLP are implemented in the toolbox and presented here. While the first approach is using the “full” memory (the whole history of the signal), the second approach uses the “restricted” memory (two, three or four previous samples). Both FLP approaches are compared to the standard linear prediction and their performance is evaluated in examples using a test signal (sine wave signal), and a real-data signal (speech signal) as the input. [less ▲]

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See detailMULTI-LEVEL INFORMATION VALUE STREAM MAPPING
Mangers, Jeff UL; Thoussaint, Lou; Minoufekr, Meysam UL et al

in International Conference on Mass Customization and Personalization (2020), 9

Digitalization and automation of the production according to Industry 4.0 opens new opportunities for companies to develop more efficient value chains. In the context of mass customization, it is ... [more ▼]

Digitalization and automation of the production according to Industry 4.0 opens new opportunities for companies to develop more efficient value chains. In the context of mass customization, it is promising to examine more closely the complete internal value chain of companies, from the first customer contact to the delivery of the finished product, prior to provide digital configurations for customized products. A critical aspect for internal inefficiencies and complication of an aspired automation are the interfaces of departments due to inconsistent and non-uniform information transfer. This article presents a versatile approach to visualize the internal information flow at inter-departmental level as well as at intra-departmental level. The described multilevel information value stream mapping method perfectly suits as prerequisite for a digitalization or automation of internal information flows. As framework for the time capturing and visualization, ISO 22468 is used, and an industrial use case exemplifies the research findings. [less ▲]

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See detailMeasuring the Environmental Exposome (ISES2020)
Schymanski, Emma UL

Scientific Conference (2020, September 21)

Detailed reference viewed: 36 (0 UL)
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See detailSchadstoffen auf der Spur mit Umweltcheminformatik
Schymanski, Emma UL

Scientific Conference (2020, September 17)

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See detaildigitizing of Research and Teaching
Plapper, Peter UL

Scientific Conference (2020, September 05)

The current Covid-19 crisis impacts all manufacturing areas and new processes are sought. This presentation provides the audience with three examples related to assembly work instructions, logistics data ... [more ▼]

The current Covid-19 crisis impacts all manufacturing areas and new processes are sought. This presentation provides the audience with three examples related to assembly work instructions, logistics data handling and manufacturing education, for which innovative ways to obtain access to context sensitive data based on digital tools are investigated. Augmented Reality (AR) and Virtual Reality (VR) facilitate access to relevant manufacturing information. In order to provide logistic warehouse workers with immediate access to shipping documents, to avoid paper print-outs, and to eliminate error-prone typing of information, critical information should be handled digitally and hands-free. To support logistic workers to efficiently document, register and trace receipt, storage or delivery of goods, the presented solution is built on hands-free digital tools with AR technology in commercially available smart glasses. Similarly, workers who execute complex assembly operations frequently require either assistance or support for the next assembly step. Depending on the context, relevant assembly process information is automatically displayed together with the environment in the AR smart glass. Thus, the operator is supported by the presented hands-free-tool to complete the next challenging tasks. Currently, teaching is being transferred from physical class-room teaching to remote or hybrid education. For this purpose, Virtual Reality (VR) provides a very welcome opportunity to complement in-presence teaching with exposure to examples of real manufacturing operations captured in videos of industrial case studies. Students apply learnings from theoretical classes to manufacturing case studies by identifying best practices and also recognizing waste. The presentation shares experience in teaching of lean methods based on AR technology to graduate engineering students. [less ▲]

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See detailNumerical Analysis of Interaction between a Reacting Fluid and a Moving Bed with Spatially and Temporally Fluctuating Porosity
Rousset, Alban UL; Mainassara Chekaraou, Abdoul Wahid UL; Besseron, Xavier UL et al

Scientific Conference (2020, August 31)

The purpose of this study is to propose a numerical approach that combines low computational costs through the use of high computing efficiency, allowing the realistic use of the design with a sufficient ... [more ▼]

The purpose of this study is to propose a numerical approach that combines low computational costs through the use of high computing efficiency, allowing the realistic use of the design with a sufficient result's accuracy for industrial applications to investigate biomass combustion in a large-scale reciprocating grate. In the present contribution, a Biomass combustion chamber of a 16 MW geothermal steam super-heater, which is part of the Enel Green Power "Cornia 2" power plant,is being investigated with high-performance computing methods. For this purpose, the extended discrete element method (XDEM) developed at the University of Luxembourg is used in an HPC environment, which includes both the moving wooden bed and the combustion chamber above it. The XDEM simulation platform is based on a hybrid four-way coupling between the Discrete Element Method (DEM) and Computational Fluid Dynamics (CFD). In this approach, particles are treated as discrete elements that are coupled by heat, mass, and momentum transfer to the surrounding gas as a continuous phase. For individual wood particles, besides the equations of motion, the differential conservation equations for mass, heat, and momentum are solved, which describe the thermodynamic state during thermal conversion. The grate system has three different moving sections to ensure good mixing of the biomass parts and appropriate residence time. The primary air enters from below the grate and is split into four different zones. Furthermore, a secondary air is injected at high velocity straight over the fuel bed through nozzles. A Flue Gas Recirculation is present and partly injected through two jets along the vertical channel and partly from below the grate. The numerical 3D model presented is based on a multi-phase approach. The biomass particles are taken into consideration via the XDEM Method, while the gaseous phase is described by CFD with OpenFOAM. Thus, the combustion of the particles on the moving beds in the furnace is processed by XDEM through conduction, radiation and conversion along with the interaction with the surrounding gas phase accounted for by CFD. The coupling of CFD-XDEM as an Euler-Lagrange model is used. The fluid phase is a continuous phase handled with an Eulerian approach and each particle is tracked with a Lagrangian approach. Energy, mass and momentum conservation is applied for every single particle and the interaction of particles with each other in the bed and with the surrounding gas phase are taken into account. An individual particle can have a solid, liquid, gas or inert material phases (immobile species) at the same time. The different phases can undergo a series of conversion through various reactions that can be homogeneous, heterogeneous or intrinsic (drying, pyrolysis, gasification and oxidation). Our first results are consistent with actual data obtained from the sampling of the residual solid in the industrial plant. Our model is also able to predict gas flux behaviour inside the furnace, particularly the flue gas recirculation on the combustion process injection. [less ▲]

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See detailSHARP 2020: The 1st Shape Recovery from Partial Textured 3D Scans Challenge Results
Saint, Alexandre Fabian A UL; Kacem, Anis UL; Cherenkova, Kseniya UL et al

Scientific Conference (2020, August 23)

The SHApe Recovery from Partial textured 3D scans challenge, SHARP 2020, is the first edition of a challenge fostering and benchmarking methods for recovering complete textured 3D scans from raw ... [more ▼]

The SHApe Recovery from Partial textured 3D scans challenge, SHARP 2020, is the first edition of a challenge fostering and benchmarking methods for recovering complete textured 3D scans from raw incomplete data. SHARP 2020 is organized as a workshop in conjunction with ECCV 2020. There are two complementary challenges, the first one on 3D human scans, and the second one on generic objects. Challenge 1 is further split into two tracks, focusing, first, on large body and clothing regions, and, second, on fine body details. A novel evaluation metric is proposed to quantify jointly the shape reconstruction, the texture reconstruction, and the amount of completed data. Additionally, two unique datasets of 3D scans are proposed, to provide raw ground-truth data for the benchmarks. The datasets are released to the scientific community. Moreover, an accompanying custom library of software routines is also released to the scientific community. It allows for processing 3D scans, generating partial data and performing the evaluation. Results of the competition, analyzed in comparison to baselines, show the validity of the proposed evaluation metrics and highlight the challenging aspects of the task and of the datasets. Details on the SHARP 2020 challenge can be found at https://cvi2.uni.lu/sharp2020/ [less ▲]

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