Brazilian Decimetric Array (Phase-I)

An East – West, one-dimensional radio interferometer array consisting of five parabolic dish antennas has been set up at Cachoeira Paulista (longitude 45°0′20″ W, latitude 22°41′19″ S) for observations of the Sun and some of the strong sidereal sources by the Instituto Nacional de Pesquisas Espaciais (INPE), Brazil. This is Phase-I of the proposed Brazilian Decimetric Array and can be operated at any frequency in the range 1.2 – 1.7 GHz. The instrument has been in operation since November 2004 onwards at 1.6 GHz. The angular and temporal resolutions at this frequency are ∼3′ and 100 ms, respectively. Details of the array, analog/digital receiver system, and a preliminary East – West one-dimensional solar image at the 1.6 GHz are presented in this paper.     

Interactive Visualization Software to Improve Relief Interpretation Skills: Spatial Data Infrastructure Geoportal versus Augmented Reality

The improvement of geospatial thinking is essential for success in science, technology, engineering, and mathematics disciplines. Training based on the geovisualization and interpretation of landforms can develop the relief interpretation skill. The research reported here focuses on the study of relief visualization and interpretation, using results from a workshop performed with forty-six university students using different displays of geovisualization in a Spatial Data Infrastructure (SDI) geoportal: LiDAR digital surface model, HillShade digital terrain model, digital elevation model, slope model, high-resolution orthophoto, and topographic map. The results are compared with those of another workshop on the same topic carried out with augmented reality (AR) technology. The relief interpretation skill improvement was measured before and after each of the workshops using the Topographic Map Assessment test. The results with the SDI geoportal showed a significant gain in relief interpretation skill between pretest and posttest scores but less than the gain obtained with AR. No differences were found due to the gender of the participants in either case. Key Words: augmented reality, geospatial thinking, landform interpretation, relief interpretation skill, Spatial Data Infrastructure.