Reconstructing cosmic acceleration from f(R) modified gravity

A variant of the accelerating cosmology reconstruction program is developed for $f(R)$ gravity. Reconstruction schemes in terms of e-foldings and by using an auxiliary scalar field are developed. An example of a model with a transient phantom behavior without real matter is explicitly discussed in both schemes. Detailed comparison of the two schemes of reconstruction is presented. It seems to support physical non-equivalence of the two frames.Comment: 3 pages. Contribution to the Proceedings of the Spanish Relativity Meeting (ERE) 2011, Madrid, Spai

Growth, fluctuations and technology in the U.S. post-war economy

This paper explores several issues concerning how technology affects growth and fluctuations during several U.S. postwar series. The nature of technology is divided into neutral progress and investment-specific progress. Accounting for several changes in the first and second order moments of these series (the slowdown of productivity in 1974, the moderation of 1984 and the resurgence in productivity after 1994), I find that the contribution of investment-specific progress to growth has increased over time. I also find that neutral progress is crucial in explaining the cyclical component of output (before and after 1984), contrary to results found in related literature. However, the shocks to investment-specific progress have played an increasing role in output and other macroeconomic variables. Finally, I conclude that moderation in the macroeconomic series can be associated with technology. In sum, the quality of technological processes affecting long run growth and fluctuations has changed over the past decades.Productivity growth; Investment-specific technological change; Neutral technological change

The role of new technologies in the economic growth of Andalucia

This paper explores the contribution of Information and Communication Technologies (ICT) on economic growth and labor productivity growth of Andalucía during 1995-2004. We find that the contribution of ICT assets to total market GVA growth is quantitatively modest. Anyway the contribution to GVA growth and employment growth within the intensive ICT sectors has experienced a considerable increase in Andalucía. Although our analysis detects that intensive ICT sectors exhibit a high productivity level with respect to that of the non intensive ones, our main conclusion is that the advantages that might emerge from the use of ICT are nor yet observable in the economic dynamics of Andalucía, at least in a similar manner to that of the most developed.Information and Communication Technologies, productivity growth, regional growth

A Security Pattern for Cloud service certification

Cloud computing is interesting from the economic, operational and even energy consumption perspectives but it still raises concerns regarding the security, privacy, governance and compliance of the data and software services offered through it. However, the task of verifying security properties in services running on cloud is not trivial. We notice the provision and security of a cloud service is sensitive. Because of the potential interference between the features and behavior of all the inter-dependent services in all layers of the cloud stack (as well as dynamic changes in them). Besides current cloud models do not include support for trust-focused communication between layers. We present a mechanism to implement cloud service certification process based on the usage of Trusted Computing technology, by means of its Trusted Computing Platform (TPM) implementation of its architecture. Among many security security features it is a tamper proof resistance built in device and provides a root of trust to affix our certification mechanism. We present as a security pattern the approach for service certification based on the use TPM.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec