In general, the location of traffic accidents is described as an address with text, so they are difficult to display on the map. The paper discusses how to utilize the geocoding technology and VRS-GPS positioning technology to record the traffic accidents with Geo-spatial information. Based on the spatial relationship between traffic accidents and road network elements, two-way association rela...

this study focused on the public transport risk assessment in district one of ​​tehran through fault tree analysis involving the three criteria of human, vehicle and road in haddon matrix. in fact, it examined the factors contributing to the occurrence of road accidents at several urban black spots within district 1. relying on road safety checklists and survey of experts, this study made an ef...

The migration of UMTS carrier frequencies to the 2 GHz band has stimulated interest in radio coverage in urban environments. This paper examines the problem of poor signal quality close to buildings. It uses simulation based on approximate propagation models in a “generic” urban environment to estimate the relationship between size of coverage black spots and distance from the serving BS. Consi...

The mechanisms of asymmetric organ development have been under intensive investigation for years, yet the proposed mechanisms remain controversial (1-3). The female Bruchus quadrimaculatus beetle insect develops two black-colored spots bilaterally located on each upper elytra wing by an unknown mechanism. Fifty percent of the P (for piebald, two colors) gene homozygous mutant insects, described...

The decision rules that animals use for distinguishing between conspecifics of different age and sex classes are relevant for understanding how closely related species interact in sympatry. In rubyspot damselflies (Hetaerina spp.), the red wing coloration of mature males is hypothesized to be a key trait for sex recognition and competitor recognition within species and the proximate trigger for...

A new tree frog species of the genus Scinax from the interfluve between the Purus and Madeira rivers, Brazilian Amazonia, is described and illustrated. The new species is diagnosed by medium body size, snout truncate in dorsal view, ulnar and tarsal tubercles absent, nuptial pads poorly developed, skin on dorsum shagreen, dorsum light brown with dark brown spots and markings, white groin with b...