Interprocess data transfer in ATLAS, a platform for distributed applications

The ATLAS platform strives to make several useful but technically involved mechanisms available to the programmer building applications over it with the least possible effort. These mechanisms include network distribution of cooperating processes, a powerful macro language, a journaling system and fault tolerance in the presence of network failures or node crashes. In this paper we discuss the techniques used in ATLAS to implement data transfer over a network between different machines with the least hassle to the programmer.Postprint (published version

Automatic code generation for ATLAS communications drivers

ATLAS is a software development platform created in our Department. Among other benefits, it provides support to easily distribute applications over a network. In these applications, communications issues among the different processes should be faced. Pursuing to isolate application developers from the intricacies of these issues, communication drivers are automatically generated from an interface declaration of each process. This automatic code generation --not unlike the generation of stubs in CORBA from the IDL specification-- is the main topic of this report.Postprint (published version

Movilidad y territorialidad. El poblamiento neolítico en las comarcas centro-meridionales valencianas

Pautas de emplazamiento y distribución de los distintos yacimientos neolíticos conocidos en las comarcas centro-meridionales valencianas

Enabling collaboration in virtual reality navigators

In this paper we characterize a feature superset for Collaborative Virtual Reality Environments (CVRE), and derive a component framework to transform stand-alone VR navigators into full-fledged multithreaded collaborative environments. The contributions of our approach rely on a cost-effective and extensible technique for loading software components into separate POSIX threads for rendering, user interaction and network communications, and adding a top layer for managing session collaboration. The framework recasts a VR navigator under a distributed peer-to-peer topology for scene and object sharing, using callback hooks for broadcasting remote events and multicamera perspective sharing with avatar interaction. We validate the framework by applying it to our own ALICE VR Navigator. Experimental results show that our approach has good performance in the collaborative inspection of complex models.Postprint (published version

Abrigos, simas y graneros. Sobre el uso de las cuevas en la Edad del Bronce en la comarca de L'Alcoià

S'hi analitzen els materials i la distribució a la comarca de l'Alcoia de les coves amb materials de l'edat del bronze. També s'interpreta el seu funcionament en el context de la intensificació de l'economia agraria en aquest moment. Puraules claus: Edat del bronze. Coves. Economia agraria. L'Alcoià.An analysis of the territorial distribution of caves in I'Alcoià area (Alicante) containing Bronze Age materials is presented. We use the material record to interpret the function of the caves in the context of the intensification of the agrarian economy that occurred during this period. Kev Words: Bronze Age. Caves. Agrarian economy. L'Alcoià (Alicante - Spain)Se analizan los materiales y la distribución en el territorio de las cuevas con materiales de la Edad del Bronce de la comarca de I'Alcoià. Interpretándose su funcionamiento en el contexto de la intensificación de la economía agraria en este momento. Palabras Clave: Edad del Bronce. Cuevas. Economía agraria. L'Alcoia

Visibility and perception of the environment. Analysis of the distribution of schematic rock art through geographic information systems

Este estudio presenta algunos resultados del cálculo de las cuencas visuales de los abrigos con Arte rupestre Esquemático en la zona centro-meridional del País Valenciano. Éstas constituyen uno de los factores cuya variación es más apreciable en las pautas de distribución de los abrigos: mientras que las visibilidades simples basadas en la distancia permiten una aproximación a las distintas estrategias de visibilidad que prima cada abrigo, el cálculo de cuencas visuales acumuladas permite definir distintos grupos, así como analizar la articulación del paisaje que se realiza con la representación de estos motivos en distintos tipos de abrigo y puntos del territorio.This paper analyses the computerised viewsheds of Schematic rock art shelters of the central Mediterranean coast of Spain. This is one of the most variable components in the patterns of distribution of the shelters. Distance based viewsheds led us to study the different visibility strategies that prevail for each shelter. The cumulative viewsheds enable us to define different groups of shelters and provide hints on the way the landscape was structured through the depiction of these motifs in different types of shelter and points in the landscape

Heterogeneous distribution in ATLAS

The ATLAS platform allows unsophisticated programmers to include advanced features in their applications with no or very little extra information and effort. These features include network distribution of cooperating processes, a powerful macro-language, a flexible journaling system and some other mechanisms directly related to graphics applications problems. In this report we describe how ATLAS is able to distribute the application processes among different architectures without needing a previous configuration information of the available processes for each architecture.Postprint (published version