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Este objeto es introductorio a la lectura de los mapas. Presenta los elementos que aparecen acompañando al campo del mapa y que le permiten realizar métricas sobre él.

Este objeto es introductorio a la lectura de los mapas. Presenta los elementos que aparecen acompañando al campo del mapa y que le permiten realizar métricas sobre él.

Este objeto es introductorio a la lectura de los mapas. Presenta los elementos que aparecen acompañando al campo del mapa y que le permiten realizar métricas sobre él.

Este objeto es introductorio a la lectura de los mapas. Presenta los elementos que aparecen acompañando al campo del mapa y que le permiten realizar métricas sobre él.

Sturgeon populations in the Danube River have experienced severe decline during the last several decades, mostly due to the poorly regulated fishery, river fragmentation and water pollution. This study focuses on gaining better understanding of sturgeon life history primarily by addressing the assessment of microelement accumulation in sturgeon pectoral fin rays, especially of strontium and calcium, as a method that can reveal migration patterns of anadromous sturgeons. Analysis was performed on pectoral fin samples of three anadromous Danube sturgeon species (beluga, Russian sturgeon and stellate sturgeon) by the use of a Nuclear Microprobe technique. The most frequent pattern in analyzed samples was represented by a low Sr:Ca ratio in the innermost annuli, followed by an increased ratio in the middle annuli segment, and often with a decreased ratio in the outermost annuli. Probability density estimate has revealed three distinguished maxima of the Sr: Ca ratio, 7.08x10(-3), 8.98x10(-3) and 9.90x10(-3), which might correspond, respectively, to fresh, brackish and saltwater. Although the analysis of the Sr: Ca ratio in sturgeon pectoral fin rays has revealed changes that might indicate probable migration between habitats with different water salinity, further studies are needed for improvement of this method. This study represents the first analysis of this kind that was conducted on sturgeon species from the Black Sea basin.

Sturgeon species in the Danube River basin have experienced severe decline. Besides overexploitation, habitat loss, and pollution, they are further endangered by lack of efficient policy and management, as well as by serious lack of knowledge about their life history. Although population viability analysis (PVA) could represent an extremely valuable tool to cope with these problems, it has not so far been applied to Danube populations. This paper represents an assessment of different PVA methods and models developed for sturgeon species. It analyzes their results, main advantages, drawbacks, and problems, and discusses the possibility of applying PVA to sturgeon populations in the Danube River basin.

Populations of six sturgeon species in the Danube River (Beluga, Russian sturgeon, Stellate sturgeon, Sterlet, Ship sturgeon and Atlantic sturgeon) have experienced severe decline during the last several decades, mostly due to the unsustainable fishery, river fragmentation and water pollution. In the present study, the question of viability of Danube sturgeon populations and the poor knowledge of their ecology have been addressed through three different research activities: 1) statistical methods that infer extinction based on sighting records have been used to assess probability of extinction of the Ship and Atlantic sturgeon, whose presence n the Danube basin is uncertain; 2) assessment of microelement accumulation in sturgeon pectoral fin rays, especially of strontium and calcium, has been conducted as a method that can reveal migration patterns of anadromous sturgeons; 3) population viability analysis in a Vortex simulation model has been conducted in order to assess the state of the six Danube sturgeon species, their future risk of extinction and to determine the most suitable conservation and management measures. Methods for inferring extinction based on sighting records provided a significant probability that the Atlantic sturgeon is extinct, with extinction occurring somewhere between 1966 and 1970, and that the Ship sturgeon is probably still present in the Danube basin, but that extinction may occur within a few decades. A new model has been also developed within the present study, able to infer probability of extinction based on the trends in sighting intervals, since this issue was not adequately considered in the existing models. Although the analysis of the strontium to calcium ratio in sturgeon pectoral fin rays has revealed changes that might indicate probable migration of juvenile fish from the river to the sea, further studies are needed for improvement of this method. Population viability analysis has revealed a large sensitivity of the Danube stu

La siguiente memoria detalla la realización de un sistema de adquisición de datos y software de supervisión de una máquina textil, en concreto, de una texturadora que produce bobinas de hilo. El objetivo principal es proveer de un programa de control de producción hecho a medida, a las máquinas texturadoras que carezcan de ello, debido a su antigüedad sin dejar de mirar la posible integración con las nuevas máquinas y tener un control completo de la planta textil. Para alcanzar el objetivo deberemos recoger la información de los sensores, que nos dan el estado de las bobinas de hilo, y registrarlos en una base de datos. Para la realización de esto se reutilizaran dispositivos que ya estaban instalados en la máquina como sensores, placas electrónicas y actuadores. También se ha creado un sistema de mulltiplexación de entradas y salidas gracias a un autómata Omron y a su programación. Por otra parte, se desarrollarán distintas aplicaciones para que nuestra solución final sea más flexible. Se implementará una aplicación que se comunicará con el autómata, otra que registrará los estados recogidos por la anterior visualizándolos por pantalla y una última para poder visualizar el estado de la máquina de manera remota mediante la red local. Para implementar las aplicaciones utilizaremos el entorno de desarrollo Visual Studio.NET 2003 y SQL Server 2000 (MSDE) como base de datos. La comprobación de que el sistema funciona se realizará mediante un pequeño prototipo que simulará el funcionamiento básico anteriormente comentado. El proyecto, tenemos que decir, que es real y está en funcionamiento con mejoras considerables en el apartado de informes históricos y control de presencia en la empresa Defiber,s.a.