Some functional forms of Blaschke-Santal\'o inequality

We establish new functional versions of the Blaschke-Santal\'o inequality on the volume product of a convex body which generalize to the non-symmetric setting an inequality of K. Ball and we give a simple proof of the case of equality. As a corollary, we get some inequalities for $\log$-concave functions and Legendre transforms which extend the recent result of Artstein, Klartag and Milman, with its equality case.Comment: 19 pages, to appear in Mathematische Zeitschrif

On the volume of sections of a convex body by cones

Let $K$ be a convex body in $\mathbb R^n$. We prove that in small codimensions, the sections of a convex body through the centroid are quite symmetric with respect to volume. As a consequence of our estimates we give a positive answer to a problem posed by M. Meyer and S. Reisner regarding convex intersection bodies.Comment: 13 page

The Wellness Companion

Issues such as obesity, high blood pressure, and heart disease have been correlated with a sedentary lifestyle. Additionally, many contemporary office jobs consist of deskwork on a computer for almost the entire workday. This can result in back and neck issues. The goal of this project is to limit the harmful effects of sitting for extended periods of time by making an active lifestyle easy and convenient. The Wellness Companion is a portable treadmill that is easy to transport and use in a variety of environments, such as at the library, in school, or at the office

Towards an integrated approach of building-data management through the convergence of building information modelling and internet of things

This contribution presents a possible use of the Building Information Model (BIM) for the implementation of Building Management Systems (BMS) and proposes tools and methods for each critical step of the process. The resulting designed process enables each building stakeholder to work at an earlier stage on the digital model located on a dedicated server. This paper proposes a novel and integrated approach to building-data management and analyses the main obstacles and limitations that may currently affect the practical implementation

De Centrale Archeologische Inventaris: een databank van archeologische vindplaatsen

Tweede artikel uit het eerste CAI-rapport uit 2004. Dit artikel handelt over de organisatie, de opbouw en de structuur van de CAI-databanken

Electron-Beam Manipulation of Silicon Dopants in Graphene

The direct manipulation of individual atoms in materials using scanning probe microscopy has been a seminal achievement of nanotechnology. Recent advances in imaging resolution and sample stability have made scanning transmission electron microscopy a promising alternative for single-atom manipulation of covalently bound materials. Pioneering experiments using an atomically focused electron beam have demonstrated the directed movement of silicon atoms over a handful of sites within the graphene lattice. Here, we achieve a much greater degree of control, allowing us to precisely move silicon impurities along an extended path, circulating a single hexagon, or back and forth between the two graphene sublattices. Even with manual operation, our manipulation rate is already comparable to the state-of-the-art in any atomically precise technique. We further explore the influence of electron energy on the manipulation rate, supported by improved theoretical modeling taking into account the vibrations of atoms near the impurities, and implement feedback to detect manipulation events in real time. In addition to atomic-level engineering of its structure and properties, graphene also provides an excellent platform for refining the accuracy of quantitative models and for the development of automated manipulation.Comment: 5 figures, 4 supporting figure

Spin-current driven Dzyaloshinskii-Moriya interaction in the multiferroic BiFeO3 from first-principles

The electrical control of magnons opens up new ways to transport and process information for logic devices. In magnetoelectrical multiferroics, the Dzyaloshinskii-Moriya (DM) interaction directly allow for such a control and, hence, is of major importance. We determine the origin and the strength of the (converse) spin current DM interaction in the R3c bulk phase of the multiferroic BiFeO3 based on density functional theory. Our data supports only the existence of one DM interaction contribution originating from the spin current model. By exploring then magnon dispersion in the full Brillouin Zone, we show that the exchange is isotropic, but the DM interaction and anisotropy prefer any propagation and any magnetization direction within the full (111) plane. Our work emphasizes the significance of the asymmetric potential induced by the spin current over the structural asymmetry induced by the anionic octahedron in multiferroics such as BiFeO3

Raman-modes of index-identified free-standing single-walled carbon nanotubes

Using electron diffraction on free-standing single-walled carbon nanotubes we have determined the structural indices (n,m) of tubes in the diameter range from 1.4 to 3nm. On the same free-standing tubes we have recorded Raman spectra of the tangential modes and the radial breathing mode. For the smaller diameters (1.4-1.7nm) these measurements confirm previously established radial breathing mode frequency versus diameter relations, and would be consistent with the theoretically predicted proportionality to the inverse diameter. However, for extending the relation to larger diameters, either a yet unexplained environmental constant has to be assumed, or the linear relation has to be abandoned.Comment: 4 pages, 4 figures, +additional materials (select PostScript to obtain it

Quand la recherche est au service des pratiques de formation à l’enseignement faisant usage du numérique, et vice-versa

Les technologies numériques sont de plus en plus présentes dans de nombreuses dimensions de nos pratiques de formation à l’enseignement. Souvent imposées rapidement et sans fondement, elles ne sont pas nécessairement intégrées de manière appropriée dans les contextes de formation universitaire ou en enseignement supérieur (Albero, 2011). Par exemple, plusieurs formateurs sont amenés à donner des cours en ligne (ou de manière hybride) sans les connaissances ou l’accompagnement nécessaire afin ..