DIGITAL COMPUTERS

Author: COBO ROMANÍ JUAN CRISTOBAL.
Year: 2004.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: FACULTAD CIENCIAS DE LA COMUNICACIÓN.
Place of preparation: ESCUELA DE POSTGRADO.

Summary: Given the growing mass of information technology is necessary to move forward in the consolidation of methodologies comunicológicas that these devices conform to the requirements. In this paper we carry out an experimental research aimed at defining methodologies that allow óptimizar usability of these information tools. This research develops experimental tests, which involved 163 subjects who evaluated different models of organizing information on the Web and then evaluated the usability according to the principles of ISO. The results show that there are criteria information architecture of Web sites that allow optimized so statistically significant, the interaction between users with different levels of technological literacy and informational these devices.

Author: MASMANO TELLO MIGUEL ÁNGEL.
Year: 2005.
University: POLITÉCNICA DE VALENCIA [www.upv.es].
Place of defense: UNIVERSIDAD POLITÉCNICA DE VALENCIA.
Place of preparation: UNIVERSIDAD POLITÉCNICA DE VALENCIA.

Summary: The management of dynamic memory appears in the early fifties to replace the previously used static memory management. Such were the benefits derived from their use, at present, it is hard to find systems that do not use it now, the majority of existing operating systems and programming languages provide some facilities to be used, either explicitly or implicitly. Among the few exceptions of systems that do not make use of dynamic memory are real-time systems. These systems whose correctness depends not only on their internal logic, but also the response time, have prevented its use mainly for two reasons: first, the memory management has always been regarded by the community as a real-time problem inherently non-deterministic temporarily . Second, the phenomenon of fragmentation, which can cause a memory manager fail in a memory allocation, despite the fact that the amount of unused memory at that time equals or exceeds the requirements. However, the recent boom in language like Java, which makes heavy use of dynamic memory by implication, and its adoption in real-time systems is forcing them to reconsider and introduce the management of dynamic memory in such systems. This thesis addresses the problem of dynamic memory management in real-time systems. First, we propose a new memory manager dynamic Two-Level Segregated Fit (TLSF), which has a fast response time and deterministic, and a fragmentation low.