Search results for "ddc:"
showing 10 items of 3080 documents
Energy of dendritic avalanches in thin-film superconductors
2018
A method for calculating stored magnetic energy in a thin superconducting film based on quantitative magneto-optical imaging is developed. Energy and magnetic moment are determined with these calculations for full hysteresis loops in a thin film of the superconductor NbN. Huge losses in energy are observed when dendritic avalanches occur. Magnetic energy, magnetic moment, sheet current and magnetic flux distributions, all extracted from the same calibrated magneto-optical images, are analyzed and discussed. Dissipated energy and the loss in moment when dendritic avalanches occur are related to each other. Calculating these losses for specific spatially-resolved flux avalanches is a great ad…
Effect of mixing and spatial dimension on the glass transition
2009
We study the influence of composition changes on the glass transition of binary hard disc and hard sphere mixtures in the framework of mode coupling theory. We derive a general expression for the slope of a glass transition line. Applied to the binary mixture in the low concentration limits, this new method allows a fast prediction of some properties of the glass transition lines. The glass transition diagram we find for binary hard discs strongly resembles the random close packing diagram. Compared to 3D from previous studies, the extension of the glass regime due to mixing is much more pronounced in 2D where plasticization only sets in at larger size disparities. For small size disparitie…
Structure and dynamics in amorphous tellurium and Te-n clusters: A density functional study
2012
Density functional/molecular dynamics simulations have been performed on amorphous tellurium (a melt-quenched sample of 343 atoms at 300 K) and on Te clusters with up to 16 atoms. The former extend our calculations on liquid Te at 560, 625, 722, and 970 K [Phys. Rev. B 81, 094202 (2010)]. We discuss trends in structures (including those of other group-16 elements), electronic densities of states, and vibration frequencies. Chain structures are common in S and Se, but the chains in amorphous Te are short, and branching sites with threefold-coordinated atoms are common. The energy difference between two- and threefold local coordination depends sensitively on the exchange-correlation function…
Most Diverse Near-Shortest Paths
2021
Computing the shortest path in a road network is a fundamental problem that has attracted lots of attention. However, in many real-world scenarios, determining solely the shortest path is not enough as users want to have additional, alternative ways of reaching their destination. In this paper, we investigate a novel variant of alternative routing, termed the k-Most Diverse Near-Shortest Paths (kMDNSP). In contrast to previous work, kMDNSP aims at maximizing the diversity of the recommended paths, while bounding their length based on a user-defined constraint. Our theoretical analysis proves the NP-hardness of the problem at hand. To compute an exact solution to kMDNSP, we present an algori…
The spectrum of weakly coupled map lattices
1998
We consider weakly coupled analytic expanding circle maps on the lattice Zd (for d 2 l), with small coupling strength c and coupling between two sites decaying exponentially with the distance. We study the spectrum of the associated (Perron-Frobenius) transfer operators. We give a FrCchet space on which the operator associated to the full system has a simple eigenvalue at 1 (corresponding to the SRB measure p* previously obtained by Bricmont-Kupiainen (BKl)) and the rest of the spectrum, except maybe for continuous spectrum, is inside a disc of radius smaller than one. For d = 1 we also construct Banach spaces of densities with respect to pr on which perturbation theory, applied to the diff…
VET workers’ problem-solving skills in technology-rich environments: European approach
2014
International journal for research in vocational education and training 1 (2014) 1, S. 57-80
Teacher trainees' experiences of the components of ICT competencies and key factors in ICT competence development in work-based vocational teacher tr…
2022
International journal for research in vocational education and training 9 (2022) 2, S. 146-166
Birth of the Biscane
2017
This paper describes the unprecedented storm Stephanie, which exhibited tropical characteristics over the Bay of Biscay on 15 September 2016. Remote sensing observations reveal a cloud-free area surrounded by a circular precipitation pattern and an axisymmetric wind field, while buoy observations show an abrupt drop in wind speed during the passage of the storm centre. Model analysis further corroborates an ongoing tropical transition from a frontal cold-core to a symmetric warm-core system. By analogy with ‘Medicanes’ (Mediterranean hurricanes), we name this storm a ‘Biscane’ (Biscay hurricane). Weather systems of this kind may become more frequent in a warmer climate.
Herbal medicinal products - Evidence and tradition from a historical perspective.
2017
Abstract Background Aside from the fully licensed herbal medicines there are products on the European pharmaceutical market which are registered by virtue of their longstanding traditional use. The normal registration procedure does not apply to them because presently they do not meet the legal requirements for a full license as set out in the relevant European Union Directive. One of these requirements, “proof of tradition”, has so far been dealt with in different ways and fails to meet the criteria of good practice. Method This analysis is based on a selective literature search in PubMed and in databases of medical and pharmaceutical history, interviews with licensing experts, a consensus…
Willingness to pay for a cure of low-risk melanoma patients in Germany
2018
Malignant melanoma is potentially life-threatening but in most cases curable if detected early. Willingness to pay (WTP) is a preference-based construct that reflects burden of disease by assessment of the monetary value for a hypothetical cure from disease. Since WTP (directly as total amount of money) has not been assessed so far in patients with low risk melanoma, it was interesting to gain insights in this patient population and then, in a second step, compare it directly with the WTP of their treating dermato-oncologists. WTP was assessed in 125 patients with low-risk melanoma and additionally in 105 treating physicians, asking for the one-time and continuous payments they would be wil…