A software toolkit for web-based virtual environments based on a shared database

We propose a software toolkit for developing complex web-based user interfaces, incorporating such things as multi-user facilities, virtual environments (VEs), and interface agents. The toolkit is based on a novel software architecture that combines ideas from multi-agent platforms and user interface (UI) architectures. It provides a distributed shared database with publish-subscribe facilities. This enables UI components to observe the state and activities of any other components in the system easily. The system runs in a web-based environment. The toolkit is comprised of several programming and other specification languages, providing a complete suite of systems design languages. We illustrate the toolkit by means of a couple of examples

Effectiveness of Visualisations for Detection of Errors in Segmentation of Blood Vessels

Vascular disease diagnosis often requires a precise segmentation of the vessel lumen. When 3D (Magnetic Resonance Angiography, MRA, or Computed Tomography Angiography, CTA) imaging is available, this can be done automatically, but occasional errors are inevitable. So, the segmentation has to be checked by clinicians. This requires appropriate visualisation techniques. A number of visualisation techniques exist, but there has been little in the way of user studies that compare the different alternatives. In this study we examine how users interact with several basic visualisations, when performing a visual search task, checking vascular segmentation correctness of segmented MRA data. These visualisations are: direct volume rendering (DVR), isosurface rendering, and curved planar reformatting (CPR). Additionally, we examine if visual highlighting of potential errors can help the user find errors, so a fourth visualisation we examine is DVR with visual highlighting. Our main findings are that CPR performs fastest but has higher error rate, and there are no significant differences between the other three visualisations. We did find that visual highlighting actually has slower performance in early trials, suggesting that users learned to ignore them

Natuur en waterberging stellen eigen eisen aan bodembeheer

Natuur en waterberging. Twee functies van de bodem die ieder een eigen beheer vragen. Hoe gaat dat in zijn werk? Een kijkje in Overijssel bij natuurgebied De Wieden, waar Natuurmonumenten voormalige landbouwgrond verschraalt. En bij de Heinose Vloedgraven, een stroomgebied dat Waterschap Groot Salland “waterproof” probeert te maken

Mengkuilen voor drachtige zeugen

Mixed silages made of grass and CCM or barley were investigated as to losses from preservation and sensitivity to overheating. Mixed silages made of wet grass (16% of dry matter) had clearly higher losses from preservation and were on average more sensitive to overheating than mixed silages made of dry grass (35% of dry matter). To decrease the risk of overheating it is recommended that an anti' overheating product is added when making mixed silage of grass with CCM or grai