Sergio Vega Sánchez

The 2009 Department of Energy Solar Decathlon and the 2010 European Solar Decathlon—expanding the global reach of zero energy homes through collegiate competitions

Beginning with the first event in Washington, DC in 2002, the Department of Energys Solar Decathlon has brought attention to the promise of PV-powered, zero-energy homes through the format of a riveting collegiate competition. As an internationally recognized event, it demonstrates innovative solutions-using energy efficiently and generating the needs of modern domestic life with solar energy. At the 2007 event (the third Solar Decathlon), a new era of the competition was conceived, in which the U.S. Department of Energys event (produced and managed by the National Renewable Energy Laboratory) would be complemented by a European Solar Decathlon in Madrid, with each competition to be held in alternating years. Each of these upcoming events is described.

A formal model for the creation and evaluation of steganographic solutions based in lexical-semantic substitutions: a case applied to Spanish

This paper develops a formal model that allows research, development and evaluation from a functional point of view and attending to security needs, of the different parts in the process of creation of a linguistic steganographic system based on the lexical-semantic substitution of words by their synonyms. The advantages and drawbacks of this type of steganographic technique and the procedure to evaluate its usefulness in a given language are discussed. As a case study, the application of this model is carried out in the Spanish language based on the development of the tool Lexical Substitution in Spanish. This tool allows the testing of the substitution of words with their synonyms in Spanish. A hiding capacity of at least 0.1864bits/word, resulting in 68.33% of the stegotexts created being invisible to the attacks analysed. This hiding capacity is useful enough to send Internet addresses, GPS coordinates, brief mobility messages, signatures on text, control messages, and so forth. All these uses are in fact very practical within the area of telecommunication networks. From the point of view of corporate network security, stegotexts make possible, for example, the control of a botnet without any knowledge on the part of the network administrators. Copyright

An ecological approach to anomaly detection: The EIA model

The presented work proposes a new approach for anomaly detection. This approach is based on changes in a population of evolving agents under stress. If conditions are appropriate, changes in the population (modeled by the bioindicators) are representative of the alterations to the environment. This approach, based on an ecological view, improves functionally traditional approaches to the detection of anomalies. To verify this assertion, experiments based on Network Intrussion Detection Systems are presented. The results are compared with the behaviour of other bioinspired approaches and machine learning techniques.