Polytechnic University of Valencia

About: Polytechnic University of Valencia is a education organization based out in Valencia, Spain. It is known for research contribution in the topics: Catalysis & Population. The organization has 16282 authors who have published 40162 publications receiving 850234 citations.

Pressure dependence of the lattice dynamics of ZnO: An ab initio approach

Abstract: We have performed first-principles calculations of the electronic structure of ZnO, and applied them to the determination of structural and lattice-dynamical properties and their dependence on pressure. The dynamical matrices have been obtained for the wurtzite, zinc-blende, and rocksalt modifications with several lattice parameters optimized for pressures up to 12 GPa. These matrices are employed to calculate the one-phonon densities of states ~DOS! and the two-phonon DOS associated with either sums or differences of phonons. These results provide the essential tools to analyze the effect of isotope-induced mass disorder and anharmonicity on phonon linewidths, which we discuss here and compare with experimental data from Raman spectroscopy, including first- and second-order spectra. Agreement of calculated properties with experimental results improves considerably when the renormalization due to anharmonicity is subtracted from the experimental data.

UJIIndoorLoc: A new multi-building and multi-floor database for WLAN fingerprint-based indoor localization problems

Abstract: Although indoor localization is a key topic for mobile computing, it is still very difficult for the mobile sensing community to compare state-of-art localization algorithms due to the scarcity of databases Thus, a multi-building and multi-floor localization database based on WLAN fingerprinting is presented in this work, being its public access granted for the research community The here proposed database not only is the biggest database in the literature but it is also the first publicly available database Among other comprehensively described features, full raw information taken by more than 20 users and by means of 25 devices is provided

Assessment of the fertiliser potential of digestates from farm and agroindustrial residues

Abstract: The sustainability of biogas production systems depends greatly on the appropriate disposal of the digestates produced. The main agrochemical characteristics of 12 digestates from the anaerobic co-digestion of farm and agroindustrial residues were determined and compared with quality standards to assess their potential use as fertilisers. The digestates have a high fertilising potential, associated mainly with their contents of NH4-N; however, their recycling in agriculture might be restricted by their Cu and Zn contents, salinity, biodegradability, phytotoxicity and hygiene characteristics, which must be addressed to obtain the maximum benefits. Such characteristics determine the need for applying pre- or post-treatments to increase digestate quality until acceptable levels. Therefore, digestate quality must be taken into account when managing the co-digestion process, including substrate selection, in order to use digestates as fertilisers without the additional cost of post-digestion conditioning treatments.

A Survey on Electric Power Demand Forecasting: Future Trends in Smart Grids, Microgrids and Smart Buildings

Abstract: Recently there has been a significant proliferation in the use of forecasting techniques, mainly due to the increased availability and power of computation systems and, in particular, to the usage of personal computers. This is also true for power network systems, where energy demand forecasting has been an important field in order to allow generation planning and adaptation. Apart from the quantitative progression, there has also been a change in the type of models proposed and used. In the `70s, the usage of non-linear techniques was generally not popular among scientists and engineers. However, in the last two decades they have become very important techniques in solving complex problems which would be very difficult to tackle otherwise. With the recent emergence of smart grids, new environments have appeared capable of integrating demand, generation, and storage. These employ intelligent and adaptive elements that require more advanced techniques for accurate and precise demand and generation forecasting in order to work optimally. This review discusses the most relevant studies on electric demand prediction over the last 40 years, and presents the different models used as well as the future trends. Additionally, it analyzes the latest studies on demand forecasting in the future environments that emerge from the usage of smart grids.