318 resultados para shadows


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Disruptive colouration is a visual camouflage composed of false edges and boundaries. Many disruptively camouflaged animals feature enhanced edges; light patches are surrounded by a lighter outline and/or a dark patches are surrounded by a darker outline. This camouflage is particularly common in amphibians, reptiles and lepidopterans. We explored the role that this pattern has in creating effective camouflage. In a visual search task utilising an ultra-large display area mimicking search tasks that might be found in nature, edge enhanced disruptive camouflage increases crypsis, even on substrates that do not provide an obvious visual match. Specifically, edge enhanced camouflage is effective on backgrounds both with and without shadows; i.e. this is not solely due to background matching of the dark edge enhancement element with the shadows. Furthermore, when the dark component of the edge enhancement is omitted the camouflage still provided better crypsis than control patterns without edge enhancement. This kind of edge enhancement improved camouflage on all background types. Lastly, we show that edge enhancement can create a perception of multiple surfaces. We conclude that edge enhancement increases the effectiveness of disruptive camouflage through mechanisms that may include the improved disruption of the object outline by implying pictorial relief.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Toledo Gate of Ciudad Real, Spain, constructed between the late 13th and early 14th centuries, is the last remaining portion of a once complete medieval city wall. It represents the long history of the city and constitutes its main heritage symbol, dividing the historic city centre from the later 19th and 20th century expansions. In October 2012, the Town Hall and the Montemadrid Foundation started the conservation works to preserve this important monument. The preliminary phase of this project included an in-depth series of scientific studies which were carried out by a multidisciplinary team focusing on archival research, historic investigations, archaeological excavations as well as material composition analysis and main treatment application tests. As a result of these studies a series of virtual 3D models were created to inform, discuss and study the monument. A first digital model permitted visualization of the gate in the 19th century and how the main entrance to the city was integrated as a fundamental part of the city walls. This virtual reconstruction also became an important part of the campaign to raise awareness among the citizens towards a monument that had remained in the shadows for the last century, isolated in a roundabout after the systematic demolition of the city walls in the late 19th century. Over the last three years and as a result of these archaeological and historic investigations and subsequent virtual models, surprisingly new and interesting data were brought to light thus permitting the establishment and corroboration of a new and updated hypothesis of the Toledo Gate that goes beyond the previous ideas. As a result of these studies a new architectural typology with construction techniques of has been suggested. This paper describes how the results of this continuous and interdisciplinary documentation process have benefitted from a computer graphic reconstruction of the gate. It highlights how virtual reconstruction can be a powerful tool for conservation decision making and awareness raising. Furthermore, the interesting results of the final reconstruction hypothesis convinced the technical team responsible for the conservation to alter some aspects of the final project physical interventions in order to focus on some of the features and conclusions discovered through the virtual model study.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

El siguiente estudio de caso analiza la influencia de la llegada de la migración infantil indocumentada centroamericana en la reformulación de la política migratoria de Estados Unidos en el período 2010-2014. Enfocándose en el caso de Honduras para dar a conocer y analizar las causas que crean las dinámicas migratorias por parte de los menores, este trabajo analiza como la llegada de estas poblaciones genera ciertos efectos en el proceso de toma de decisión de las políticas internas de los Estados Unidos. Por un lado, para resaltar las características del fenómeno migratorio, se utilizan las teorías de redes sociales y la teoría push and pull. Por otro, mediante los conceptos de Sensibilidad y Vulnerabilidad expuestos en la teoría de la Interdependencia Compleja de las Relaciones Internacionales, como también el concepto de Seguridad Societal propuesto por Barry Buzan se estudia el nivel de influencia del fenómeno infantil en el gobierno norteamericano.