Viewshed (or visibility map) computation is an important component in many GIScience applications and, as nowadays there are huge volume of terrain data available at high resolutions, it is important to develop efficient algorithms to process these data. Since the main improvements on modern processors come from multi-core architectures, parallel programming provides a promising means for devel...

The Nasca lines or geoglyphs in southern Peru are known as one of archaeology's greatest mysteries. Since the 1980s, however, new approaches have helped to better understand their function and meaning. The recent photogrammetric recording of 1 500 geoglyphs in the vicinity ofPalpa enabled for the first time a GIS-based analysis. Geoglyph visibility is one of their most discussed traits. While m...

We present an approach to determine the credibility of content provided within a visual VGI source such as Flickr. We propose analysing the variability of selected user and photo metadata of geotagged Flickr photos with the location correctness of these images, which is our reference quality measure. These observed user and photo metadata can help to infer the credibility of contributors.

Diatoms are mostly aquatic plants, growing in various environmental conditions and habitat. Because of their high sensitivity to variations rapid response degradation, they used as biological indicators. This study aimed analyses the physicochemical parameters diatoms assemblages waterfalls. will allow determining key factors that responsible for both Podostemaceae spatial temporal distribution...

Premise The genetic structure between plant populations is facilitated by the spatial population arrangement and limited dispersal of seed pollen. Saxifraga acerifolia, a local endemic species in Japan, habitat specialist that confined to waterfalls riparian environments. Its sister species, fortunei, generalist widely distributed along riverbanks. Here, we examined sympatric two test whether d...

ABSTRACT Recently, for energy saving in wireless sensor networks, the data aggregation technique has been proposed. In this paper, we discuss the trade off between communication delay and energy consumption of the technique. At first, we analyze the full aggregation compared with nonaggregation with Markovian chain and simulation. The result shows that non-aggregation method suffers large energ...

The genus Liancalus Loew is revised for the Nearctic Region. Seven species are documented from this region including two new species: Liancalusgenualis Loew, Liancalushydrophilus Aldrich, Liancaluslimbatus Van Duzee, Liancaluspterodactyl sp. n., Liancalusquerulus Osten Sacken, Liancalussimilis Aldrich, and Liancalussonorus sp. n. Lectotypes are designated for the following species: Liancalusgen...

Water striders of the subfamily Eotrechinae from the Phetchabun Mountain Range can be found at the margins of rock pools and puddles, and in hygropetric habitats including waterfalls. Twenty-two species in three genera are known from Thailand. In the Phetchabun Mountain Range, 12 species representing all three genera were recorded from over a decade of collections (2002-2012). This paper provid...