Haptic Water; Haptics on an Animated Surface

Haptic rendering is becoming an important element of multimodal interaction. Often a real-time coupling between haptics and visualization is required, based upon an underlying physical model. In this paper, we study haptic rendering and visualization of the generation of waves in shallow water. For applications, it is usually more important to come up with a believable simulation, rather than a physically accurate simulation. Therefore our focus was on obtaining suitable simplifications of the Kas-Miller model, and incorporation into a multimodal environment, aiming at haptic rendering and real-time visualization of waves. The result has been implemented and tested using a Haptic Master device, produced by FCS Control Systems

Evaluation of the probing profile of scanning force microscopy tips

It is demonstrated that a high-temperature-treated (305) surface of a SrTiO3 crystal can be used to evaluate the probing profile of AFM tips routinely, to provide a means of selecting perfect tips and to evaluate possible image distortions. This is important in order to recognize typical AFM artifacts which are caused by tips with truncated or twinned peaks which occur rather often in the case of microfabricated AFM needles. By means of selected needles, it is shown that also defective tips can give apparently rather perfect atomic resolution from flat crystal surfaces. Scope and limitations of the resolution of structural defects are discussed as the criterion for real atomic resolution

How do pupils understand historical time?:Some evidence from England and the Netherlands

One of the key aims of the English history National Curriculum is to ensure that pupils, ‘know and understand the history of these islands as a coherent, chronological narrative’. Teaching chronology is also important in the Netherlands. In this article we describe the Dutch curriculum and discuss research currently being undertaken which may inform our teaching about the understanding of time

Calibration and evaluation of scanning-force-microscopy probes

It is demonstrated that a stepped (305) surface of a SrTiO3 crystal can be used routinely to evaluate the probing profile of scanning-force-microscopy probes. This provides a means to select optimal surface probes, and to evaluate possible image distortions within the range of the atomic and nanometer scale. The scope and limitations of the resolution of structural defects are discussed as a criterion for a true atomic resolution

‘Everything was black and white … ’: primary school pupils’ naive reasoning while situating historical phenomena in time

This study focuses on problems in pupils’ reasoning when they situate historical phenomena in time. The context is the Dutch curriculum with 10 eras and characteristic features, which was implemented to support pupils in orientating themselves in time. Twenty-two pupils aged 6–12 conducted assignments in which they had to place historical phenomena in time. Next to problems that were described in previous studies, problems were identified that related to the names and icons of the 10 eras, which sometimes helped, but also hindered pupils in their reasoning. Awareness of these problems is helpful for teachers, teacher trainers and educational policymakers

Fermi-surface topological phase transition and horizontal order-parameter nodes in CaFe2_2As2_2 under pressure

Iron-based compounds (IBS) display a surprising variety of superconducting properties that seems to arise from the strong sensitivity of these systems to tiny details of the lattice structure. In this respect, systems that become superconducting under pressure, like CaFe$_2$As$_2$, are of particular interest. Here we report on the first directional point-contact Andreev-reflection spectroscopy (PCARS) measurements on CaFe$_2$As$_2$ crystals under quasi-hydrostatic pressure, and on the interpretation of the results using a 3D model for Andreev reflection combined with ab-initio calculations of the Fermi surface (within the density functional theory) and of the order parameter symmetry (within a random-phase-approximation approach in a ten-orbital model). The almost perfect agreement between PCARS results at different pressures and theoretical predictions highlights the intimate connection between the changes in the lattice structure, a topological transition in the hole-like Fermi surface sheet, and the emergence on the same sheet of an order parameter with a horizontal node line.Comment: 13 pages, 8 color figures. This is an author-created, un-copyedited version of an article published in Scientific Reports. The published version is available online, together with Supplementary Information, at http://www.nature.com/articles/srep2639

Verlichting bij leghennen in volieresystemen

In juni 2000 is een nieuw koppel leghennen geplaatst in stal P5 van het Praktijkcentrum 'Het Spelderholt'. Er wordt onder andere onderzoek gedaan met bruine leghennen in twee voliOresystemen met twee verschillende verlichtingssystemen. In dit artikel gaan we in op de tussentijdse resultaten van het verlichtingsonderzoek in de voliOresystemen

Systeem van de toekomst voor leghennen

Het Praktijkonderzoek Veehouderij wil samen met andere kennisinstellingen de huidige inzichten gebruiken om te komen tot een geheel nieuw houderijsysteem. Uitgangspunt bij dit systeem van de toekomst is dat het op zijn minst moet passen binnen de voorwaarden van duurzame huisvestingssystemen voor leghennen