Last 7 days
Bookmark and Share    
Full Text
Peer Reviewed
See detailDismountable Flooring Systems for Multiple Use
Odenbreit, Christoph UL; Kozma, Andras UL

in IOP Conference Series: Earth and Environmental Science (2019, February), 225

Steel shapes our modern world as an integral part of the global construction economy. In the last decades, the sustainability of steel grew and turned from a linear to a circular business, where the ... [more ▼]

Steel shapes our modern world as an integral part of the global construction economy. In the last decades, the sustainability of steel grew and turned from a linear to a circular business, where the material is fully recovered and recycled after use. The RFCS Research Project “REDUCE” of the European Commission goes one step beyond the mere material recycling and investigates, how the circular economy’s philosophy can be used to reduce the carbon footprint furthermore. On that basis, one target of the research was to develop basic modular and standardised structural load bearing elements which can be adapted in the building or assembled, properly disassembled and partly or entirely be reused again in a subsequent building. This paper presents the respective research results of demountable flooring- and beam systems: 15 large scale push-out tests and two large scale composite beam tests as well as numerous finite element simulations with ABAQUS have been performed at the Laboratory of the ArcelorMittal Chair of Steel and Façade Engineering. The suitability for dis- and re-assembly as well as the strength, stiffness, slip capacity and ductility have been determined. The investigated systems included pre-stressed and epoxy injected systems, as well as solid slabs and composite slabs with profiled decking. The results showed sometimes higher resistances and smaller displacement capacities than conventional systems. The numerical simulation results were presented as well as the results of the laboratory tests. First assessments were given about the respective consequences and about how these consequences could be considered in the layout of future steel composite structures. [less ▲]

Detailed reference viewed: 7 (0 UL)
Full Text
Peer Reviewed
See detailSignal Processing for High-Throughput Satellites: Challenges in New Interference-Limited Scenarios
Perez, Ana; Vazquez, Miguel; Shankar, Bhavani UL et al

in IEEE Signal Processing Magazine (2019)

The field of satellite communications (SatCom) is enjoying renewed attention in the global telecommunications market, and high-throughput satellites, with their multiple spot beams, are critical ... [more ▼]

The field of satellite communications (SatCom) is enjoying renewed attention in the global telecommunications market, and high-throughput satellites, with their multiple spot beams, are critical components for delivering the rates that will be demanded in the future. In this article, we present the state of the art and the open research challenges in the area of high-throughput satellites, with a focus on signal processing approaches for efficient interference mitigation. [less ▲]

Detailed reference viewed: 15 (0 UL)
Full Text
Peer Reviewed
See detailA Bourdieusian approach to class‐related inequalities: the role of capitals and capital structure in the utilisation of healthcare services in later life
Paccoud, Ivana UL; Nazroo, James; Leist, Anja UL

in Sociology of Health and Illness (2019)

This paper draws on Bourdieu's theory of economic, social and cultural capital to understand the relative effect of the volume and the composition of these capitals on healthcare service use in later life ... [more ▼]

This paper draws on Bourdieu's theory of economic, social and cultural capital to understand the relative effect of the volume and the composition of these capitals on healthcare service use in later life. Based on data from the fifth wave of the Survey of Health, Aging, and Retirement in Europe (n = 64,840), we first look at the contribution of each capital in the use of three healthcare services (general practitioner, dentist and hospital). Using cluster analysis, we then mobilise Bourdieu's concept of habitus to explain how the unequal distribution of material and non‐material capitals acquired in childhood lead to different levels of health and hospital care utilisation in later life. After controlling for demographic and health insurance variables, our results show that economic capital has the strongest individual association among the three capitals. However, the results of a cluster analysis used to distinguish between capital structures show that those with high non‐material capital and low material capital have higher levels of primary healthcare utilisation, and in turn lower levels of hospital use. Bourdieu's approach sheds light on the importance of capitals in all forms and structures to understand the class‐related mechanisms that contribute to different levels of healthcare use. [less ▲]

Detailed reference viewed: 29 (3 UL)
Full Text
Peer Reviewed
See detailTraining binary classifiers as data structure invariants
Molina, Facundo; Degiovanni, Renzo Gaston UL; Ponzio, Pablo et al

in Proceedings of the 41st International Conference on Software Engineering ICSE 2019, Montreal, QC, Canada, May 25-31, 2019 (2019)

We present a technique that enables us to distinguish valid from invalid data structure objects. The technique is based on building an artificial neural network, more precisely a binary classifier, and ... [more ▼]

We present a technique that enables us to distinguish valid from invalid data structure objects. The technique is based on building an artificial neural network, more precisely a binary classifier, and training it to identify valid and invalid instances of a data structure. The obtained classifier can then be used in place of the data structure’s invariant, in order to attempt to identify (in)correct behaviors in programs manipulating the structure. In order to produce the valid objects to train the network, an assumed-correct set of object building routines is randomly executed. Invalid instances are produced by generating values for object fields that “break” the collected valid values, i.e., that assign values to object fields that have not been observed as feasible in the assumed-correct program executions that led to the collected valid instances. We experimentally assess this approach, over a benchmark of data structures. We show that this learning technique produces classifiers that achieve significantly better accuracy in classifying valid/invalid objects compared to a technique for dynamic invariant detection, and leads to improved bug finding. [less ▲]

Detailed reference viewed: 30 (3 UL)
Full Text
See detailUnramifiedness of weight one Hilbert Hecke algebras
Deo, Shaunak; Dimitrov, Mladen; Wiese, Gabor UL

E-print/Working paper (2019)

We prove that the Galois pseudo-representation valued in the mod p^n parallel weight 1 Hecke algebra for GL(2) over a totally real number field F is unramified at a place above p if p-1 does not divide ... [more ▼]

We prove that the Galois pseudo-representation valued in the mod p^n parallel weight 1 Hecke algebra for GL(2) over a totally real number field F is unramified at a place above p if p-1 does not divide the ramification index at that place. A novel geometric ingredient is the construction and study, in the case when p ramifies in F, of generalised Theta-operators using Reduzzi-Xiao's generalised Hasse invariants, including especially an injectivity criterion in terms of minimal weights. [less ▲]

Detailed reference viewed: 18 (3 UL)
Full Text
Peer Reviewed
See detailCritical size limits for collinear and spin-spiral magnetism in $CoCr_2\mathrmO_4$
Zákutná, D.; Alemayehu, A.; Vlček et al

in Physical Review. B, Condensed Matter and Materials Physics (2019), 100

The multiferroic behavior of CoCr2O4 results from the appearance of conical spin-spiral magnetic ordering, which induces electric polarization. The magnetic ground state has a complex size-dependent ... [more ▼]

The multiferroic behavior of CoCr2O4 results from the appearance of conical spin-spiral magnetic ordering, which induces electric polarization. The magnetic ground state has a complex size-dependent behavior, which collapses when reaching a critical particle size. Here the magnetic phase stability of CoCr2O4 in the size range of 3.6–14.0 nm is presented in detail using the combination of neutron diffraction with XYZ polarization analysis and macroscopic magnetization measurements. We establish critical coherent domain sizes for the formation of the spin spiral and ferrimagnetic structure and reveal the evolution of the incommensurate spin spiral vector with particle size. We further confirm the presence of ferroelectric polarization in the spin spiral phase for nanocrystalline CoCr2O4. [less ▲]

Detailed reference viewed: 22 (1 UL)
Full Text
Peer Reviewed
See detailAn evolutionary approach to translating operational specifications into declarative specifications
Molina, Facundo; Cornejo, César; Degiovanni, Renzo Gaston UL et al

in Science of Computer Programming (2019), 181

Various tools for program analysis, including run-time assertion checkers and static analyzers such as verification and test generation tools, require formal specifications of the programs being analyzed ... [more ▼]

Various tools for program analysis, including run-time assertion checkers and static analyzers such as verification and test generation tools, require formal specifications of the programs being analyzed. Moreover, many of these tools and techniques require such specifications to be written in a particular style, or follow certain patterns, in order to obtain an acceptable performance from the corresponding analyses. Thus, having a formal specification sometimes is not enough for using a particular technique, since such specification may not be provided in the right formalism. In this paper, we deal with this problem in the increasingly common case of having an operational specification, while for analysis reasons requiring a declarative specification. We propose an evolu- tionary approach to translate an operational specification written in a sequen- tial programming language, into a declarative specification, in relational logic. We perform experiments on a benchmark of data structure implementations, for which operational invariants are available, and show that our evolutionary computation based approach to translating specifications achieves very good precision in this context, and produces declarative specifications that are more amenable to analyses that demand specifications in this style. This is assessed in two contexts: bounded verification of data structure invariant preservation, and instance enumeration using symbolic execution aided by tight bounds. [less ▲]

Detailed reference viewed: 37 (2 UL)
Full Text
Peer Reviewed
See detailCase Law Highlights - March-August 2019
Haslehner, Werner UL; Deprez, Christian UL

in Revue de Droit Fiscal (2019)

Case law Hightlight regarding: 1° Administrative Court, 9 July 2019, n°41873C1 – Tax procedure and treaty qualification of liquidation proceeds; 2° Administrative Court, 2 July 2019, n°42250C2: When are ... [more ▼]

Case law Hightlight regarding: 1° Administrative Court, 9 July 2019, n°41873C1 – Tax procedure and treaty qualification of liquidation proceeds; 2° Administrative Court, 2 July 2019, n°42250C2: When are accountants “information holders” for EoI purposes?; 3° Administrative Court on hidden profit distributions; Debt forgiveness and share depreciation (31 July 2019, n°42326C3) and excessive interest (17 July 2019, n°42043C4), [less ▲]

Detailed reference viewed: 19 (1 UL)
Full Text
Peer Reviewed
See detailDroit international privé de l'Union européenne (2018)
Kinsch, Patrick UL; d'Avout, Louis, and others

in Journal du Droit International (2019)

Detailed reference viewed: 56 (1 UL)
Full Text
See detailFirst-principles approaches to the description of indirect absorption and luminescence spectroscopy: exciton-phonon coupling in hexagonal boron nitride
Paleari, Fulvio UL

Doctoral thesis (2019)

The development of novel optoelectronic applications crucially depends on the detailed understanding of light--matter interaction in the candidate materials. From a theoretical point of view, this task is ... [more ▼]

The development of novel optoelectronic applications crucially depends on the detailed understanding of light--matter interaction in the candidate materials. From a theoretical point of view, this task is especially difficult in the case of quasi--2D semiconductors, since their optical response is dominated by strongly bound excitons and many--body perturbation theory (MBPT) must be employed together with first--principles computer simulations. The case of hexagonal boron nitride (hBN) is interesting because its large band gap and high absorption/emission efficiency make it amenable for the fabrication of UV emitting devices. However, the specific microscopic mechanisms that govern the appearance of complex fine structures in the optical spectra of different types of hBN samples (monolayers, few--layers, bulk samples) are poorly understood, leading to discrepancies between experimental and theoretical results. In this Thesis, we first show how the interlayer interaction in multilayers leads to a Davydov splitting of the excitonic states of single--layer hBN. We study and characterize the absorption spectra in single layer, multilayer and bulk hBN systems, focusing on the exciton symmetry and optical activity. We show that in multilayers, Davydov splitting leads to a surface localization of the lowest--lying optically active excitons. These additional spectral features still cannot explain, by themselves, the experimentally measured optical fine structure. Therefore, we calculate exciton dispersion curves in order to search for the existence of indirect excitons with lower energy than the lowest direct exciton. We find that in bilayer hBN the nature of the optical gap (direct) changes with respect to the single--particle gap (indirect). In contrast, in bulk hBN (and thicker few--layers of hBN) both optical and quasiparticle gaps are indirect, i.e., they display a pronounced minimum in the excitonic dispersion curve between $\Gamma$ and K. %in accordance with the single--particle gap. If the lowest exciton is indirect, as in bulk hBN, then phonon--assisted transitions become relevant for the description of the optical spectra. The reliable \textit{ab initio} description of exciton--phonon coupling in indirect absorption and emission is the main focus of this Thesis. We have tackled the problem with two approaches. In the static approach, we calculate the coupling of excitons with phonons in a supercell via a finite--displacement method. The supercell is commensurate with the $k$--point corresponding to the minimum of the exciton dispersion. In this way, we are able to reproduce the rich fine structure in the luminescence spectrum of bulk hBN in good agreement with experiment and to explain it in terms of exciton--phonon coupling. The finite--displacement approach is supposed to work for indirect optical spectra in any material where the minimum of the exciton dispersion gives the dominant phonon--assisted contribution. Since in the absorption case this is not always true, we have employed a second, perturbative approach for the description of indirect absorption spectra which also includes dynamical effects and a microscopic treatment of the coupling. We have implemented the required many--body quantities (namely, the exciton--phonon coupling matrix elements and self--energy) in the \texttt{Yambo} many--body code. We expect this new method to allow us to overcome many of the theoretical limitations of previous approaches to indirect absorption. [less ▲]

Detailed reference viewed: 60 (3 UL)
Full Text
Peer Reviewed
See detailAbsence of TRIM32 Leads to Reduced GABAergic Interneuron Generation and Autism-like Behaviors in Mice via Suppressing mTOR Signaling
Zhu, Jian-Wei; Zou, Ming-Ming; Li, Yi-Fei et al

in Cerebral Cortex (2019)

Detailed reference viewed: 15 (2 UL)
Full Text
Peer Reviewed
See detailThe interplay of personality and attitudes toward own aging across two decades of later life
Kornadt, Anna Elena UL; Siebert, Jelena S.; Wahl, Hans-Werner

in PLoS One (2019), 14(10),

Big Five personality traits are assumed to be linked with attitudes toward own aging. Since both constructs have central importance for the aging process, it is surprising that to our knowledge no study ... [more ▼]

Big Five personality traits are assumed to be linked with attitudes toward own aging. Since both constructs have central importance for the aging process, it is surprising that to our knowledge no study so far comprehensively addressed their mutual connection over time. We used data from the ILSE study, a longitudinal study capturing personality and attitudes toward own aging at four measurement occasions, spanning 20 years and including two participant cohorts in midlife (n = 501; born 1950–52) and later life (n = 500; born 1930–32). Dual latent change score models showed that personality was longitudinally related to change in attitudes toward own aging: Lower Neuroticism, higher Conscientiousness, and higher Openness predicted more positive attitudes, whereas the direction of the effect for Extraversion varied by time. Furthermore, the role of personality seems to be confined to certain sensitive periods in midlife and early old age. Contrary to our expectations, attitudes toward own aging had only marginal longitudinal impact on the Big Five. Our results shed light on the developmental co-dynamics of personality and subjective perceptions of aging across the second half of the lifespan. [less ▲]

Detailed reference viewed: 9 (0 UL)
See detailLuhmann's system and the Future of Legal Global Legal System
Sosoe, Lukas UL

Speeches/Talks (2019)

Detailed reference viewed: 20 (0 UL)
Full Text
Peer Reviewed
See detailPreparation for Old Age – The Role of Cultural Context and Future Perceptions
Kornadt, Anna Elena UL; Voss, Peggy; Fung, Helene H. et al

in The Journals of Gerontology. Series B. Psychological Sciences and Social Sciences (2019), 74(4), 609--619

Detailed reference viewed: 8 (0 UL)
Peer Reviewed
See detailLife span development
Wurm, Susanne; Kornadt, Anna Elena UL

in Danan, Gu; Dupre, Matthew E (Eds.) Encyclopedia of Gerontology and Population Aging (2019)

Detailed reference viewed: 6 (0 UL)
Full Text
Peer Reviewed
See detailPolygenic Scores for Education, Health, and Personality as Predictors of Subjective Age Among Older Individuals of European Ancestry: Evidence From the Health and Retirement Study
Stephan, Yannick; Sutin, Angelina R.; Kornadt, Anna Elena UL et al

in PSYCHOLOGY AND AGING (2019), 34(1), 139-144

The present study aimed to identify whether polygenic scores (PGSs) for education, health and psychological factors are related to subjective age in a large sample of older adults. Participants were 7,763 ... [more ▼]

The present study aimed to identify whether polygenic scores (PGSs) for education, health and psychological factors are related to subjective age in a large sample of older adults. Participants were 7,763 individuals of European ancestry (57% women, Mean age = 69.15, SD = 10.18) from the Health and Retirement Study who were genotyped and provided subjective age data. Higher PGSs for educational achievement and well-being were related to a younger subjective age, whereas higher PGSs for neuroticism, body mass index, waist circumference, and depressive symptoms were associated with an older subjective age. This study provides new evidence on the potential genetic underpinnings of subjective age. [less ▲]

Detailed reference viewed: 8 (0 UL)
Full Text
Peer Reviewed
See detailMethods for mitigating disruptions in complex supply chain structures: a systematic literature review
Bier, Tobias; Lange, Anne UL; Glock, Christoph

in International Journal of Production Research (2019)

Detailed reference viewed: 116 (0 UL)
Full Text
Peer Reviewed
See detailCan we see defects in capacitance measurements of thin‐film solar cells ?
Werner, Florian UL; Babbe, Finn UL; Elanzeery, Hossam UL et al

in Progress in Photovoltaics (2019), 27

Detailed reference viewed: 99 (0 UL)