35 research outputs found
Turning Point Scotland's Housing First Project Evaluation: Final Report
GIS maps are one kind of complex display in which people search for targets. Recent studies have shown that the choice of colour-scales when displaying these maps has important implications for people's strategies in searching these displays (Donnelly, Cave, Welland & Menneer, 2006). The current study follows up on this research. Observers searched for multiple targets in each display. Two targets were red and two were blue, and targets were not very salient. Observers searched until all targets were found. This often took several seconds and many fixations. The order in hich observers found targets suggested that they were more reliant on search for particular colours under some color-scales than under others. What will be presented here is a number of oculomotor measures used to explore how search was guided in the displays: the degree to which fixations clustered around targets, the image characteristics of regions of the display that were fixated, and goodness of fit to fixation distributions of Itti & Koch saliency maps, where the features used to compute saliency were varied. The goal was to see which measures would best pick up on differences in what guided search through complex display
GPU Accelerated Particle Visualization with Splotch
Splotch is a rendering algorithm for exploration and visual discovery in
particle-based datasets coming from astronomical observations or numerical
simulations. The strengths of the approach are production of high quality
imagery and support for very large-scale datasets through an effective mix of
the OpenMP and MPI parallel programming paradigms. This article reports our
experiences in re-designing Splotch for exploiting emerging HPC architectures
nowadays increasingly populated with GPUs. A performance model is introduced
for data transfers, computations and memory access, to guide our re-factoring
of Splotch. A number of parallelization issues are discussed, in particular
relating to race conditions and workload balancing, towards achieving optimal
performances. Our implementation was accomplished by using the CUDA programming
paradigm. Our strategy is founded on novel schemes achieving optimized data
organisation and classification of particles. We deploy a reference simulation
to present performance results on acceleration gains and scalability. We
finally outline our vision for future work developments including possibilities
for further optimisations and exploitation of emerging technologies.Comment: 25 pages, 9 figures. Astronomy and Computing (2014
Interactive 3D visualization for theoretical Virtual Observatories
Virtual Observatories (VOs) are online hubs of scientific knowledge. They
encompass a collection of platforms dedicated to the storage and dissemination
of astronomical data, from simple data archives to e-research platforms
offering advanced tools for data exploration and analysis. Whilst the more
mature platforms within VOs primarily serve the observational community, there
are also services fulfilling a similar role for theoretical data. Scientific
visualization can be an effective tool for analysis and exploration of datasets
made accessible through web platforms for theoretical data, which often contain
spatial dimensions and properties inherently suitable for visualization via
e.g. mock imaging in 2d or volume rendering in 3d. We analyze the current state
of 3d visualization for big theoretical astronomical datasets through
scientific web portals and virtual observatory services. We discuss some of the
challenges for interactive 3d visualization and how it can augment the workflow
of users in a virtual observatory context. Finally we showcase a lightweight
client-server visualization tool for particle-based datasets allowing
quantitative visualization via data filtering, highlighting two example use
cases within the Theoretical Astrophysical Observatory.Comment: 10 Pages, 13 Figures, Accepted for Publication in Monthly Notices of
the Royal Astronomical Societ
Integrating virtual reality and GIS tools for geological mapping, data collection and analysis: an example from Metaxa Mine, Santorini (Greece)
In the present work we highlight the effectiveness of integrating different techniques and tools for better surveying, mapping and collecting data in volcanic areas. We use an Immersive Virtual Reality (IVR) approach for data collection, integrated with Geographic Information System (GIS) analysis in a well-known volcanological site in Santorini (Metaxa mine), a site where volcanic processes influenced the island’s industrial development, especially with regard to pumice mining. Specifically, we have focused on: (i) three-dimensional (3D) high-resolution IVR scenario building, based on Structure from Motion photogrammetry (SfM) modeling; (ii) subsequent geological survey, mapping and data collection using IVR; (iii) data analysis, e.g., calculation of extracted volumes, as well as production of new maps in a GIS environment using input data directly from the IVR survey; and finally, (iv) presentation of new outcomes that highlight the importance of the Metaxa Mine as a key geological and volcanological geosite
An Innovative Science Gateway for the Cherenkov Telescope Array
The Cherenkov Telescope Array (CTA) is an initiative to build the next generation, ground-based gamma-ray observatories. We present a prototype workspace developed at INAF that aims at providing innovative solutions for the CTA community. The workspace leverages open source technologies providing web access to a set of tools widely used by the CTA community. Two different user interaction models, connected to an authentication and authorization infrastructure, have been implemented in this workspace. The first one is a workflow management system accessed via a science gateway (based on the Liferay platform) and the second one is an interactive virtual desktop environment. The integrated workflow system allows to run applications used in astronomy and physics researches into distributed computing infrastructures (ranging from clusters to grids and clouds). The interactive desktop environment allows to use many software packages without any installation on local desktops exploiting their native graphical user interfaces. The science gateway and the interactive desktop environment are connected to the authentication and authorization infrastructure composed by a Shibboleth identity provider and a Grouper authorization solution. The Grouper released attributes are consumed by the science gateway to authorize the access to specific web resources and the role management mechanism in Liferay provides the attribute-role mapping