Search results for "Energy source"
showing 10 items of 615 documents
The X-ray Luminosity - Velocity Dispersion relation in the REFLEX Cluster Survey
2003
We present an estimate of the bolometric X-ray luminosity - velocity dispersion L_x - sigma_v relation measured from a new, large and homogeneous sample of 171 low redshift, X-ray selected galaxy clusters. The linear fitting of log(L_x) - log(sigma_v) gives L_x = 10^{32.72 \pm 0.08} sigma^{4.1 \pm 0.3}_v erg s^{-1} h^{-2}_{50}. Furthermore, a study of 54 clusters, for which the X-ray temperature of the intracluster medium T is available, allows us to explore two other scaling relations, L_x -T and sigma_v -T. From this sample we obtain L_x \propto T^{3.1 \pm 0.2} and sigma_v \propto T^{1.00 \pm 0.16}, which are fully consistent with the above result for the L_x-sigma_v. The slopes of L_x -T…
A Monte Carlo-based dosimetric characterization of Esteya® , an electronic surface brachytherapy unit
2018
PURPOSE The purpose of this work is threefold: First, to obtain the phase space of an electronic brachytherapy (eBT) system designed for surface skin treatments. Second, to explore the use of some efficiency enhancing (EFEN) strategies in the determination of the phase space. Third, to use the phase space previously obtained to perform a dosimetric characterization of the Esteya eBT system. METHODS The Monte Carlo study of the 69.5 kVp x-ray beam of the Esteya® unit (Elekta Brachytherapy, Veenendaal, The Netherlands) was performed with PENELOPE2014. The EFEN strategies included the use of variance reduction techniques and mixed Class II simulations, where transport parameters were fine-tune…
Measurement ofνμ-induced charged-current neutral pion production cross sections on mineral oil atEν∈0.5–2.0 GeV
2011
The authors would like to acknowledge the support of Fermilab, the Department of Energy, and the National Science Foundation in the construction, operation, and data analysis of the Mini Booster Neutrino Experiment.
Intracluster Medium reheating by relativistic jets
2011
Galactic jets are powerful energy sources reheating the intra-cluster medium in galaxy clusters. Their crucial role in the cosmic puzzle, motivated by observations, has been established by a great number of numerical simulations missing the relativistic nature of these jets. We present the first relativistic simulations of the very long term evolution of realistic galactic jets. Unexpectedly, our results show no buoyant bubbles, but large cocoon regions compatible with the observed X-ray cavities. The reheating is more efficient and faster than in previous scenarios, and it is produced by the shock wave driven by the jet, that survives for several hundreds of Myrs. Therefore, the X-ray cavi…
A sliding mass wave energy converter
2019
This paper presents a wave energy converter which is based on a sliding mass coupled to a linear generator. In order to maximize energy extraction, the stochastic features of the energy source has been included in the mathematical model of the system in order to satisfactorily tackle the problem. The results of several simulations are presented.
Cold exposure enhances fat utilization but not non-esterified fatty acids, glycerol or catecholamines availability during submaximal walking and runn…
2013
Cold exposure modulates the use of carbohydrates and fat during exercise. This phenomenon has mostly been observed in controlled cycling studies, but not during walking and running when core temperature and oxygen consumption are controlled, as both may alter energy metabolism. This study aimed at examining energy substrate availability and utilization during walking and running in the cold when core temperature and oxygen consumption are maintained. Ten lightly clothed male subjects walked or ran for 60-min, at 50% and 70% of maximal oxygen consumption, respectively, in a climatic chamber set at 0°C or 22°C. Thermal, cardiovascular, and oxidative responses were measured every 15-…
Reduction of Nitrates in Waste Water through the Valorization of Rice Straw: LIFE LIBERNITRATE Project
2018
An improved and more sustainable waste management system is required for successful development of technologies based on renewable sources. Rice straw is submitted to controlled combustion reactions and the produced ashes are chemically treated to produce silica. After a chemical activation step, the activated silica shows potential as an adsorbent agent and will be used to remove the excess of nitrates in groundwater and wells in the area of Alginet (Valencia, Spain), selected as a vulnerable zone within the Nitrates Directive. The demonstration activity aims to have a local impact on municipalities of 200 inhabitants or fewer, decreasing from current nitrate concentrations close to 50 mg/…
Smart grid-aware scheduling in data centres
2015
In several countries the expansion and establishment of renewable energies result in widely scattered and often weather-dependent energy production, decoupled from energy demand. Large, fossil-fuelled power plants are gradually replaced by many small power stations that transform wind, solar and water power into electrical power. This leads to changes in the historically evolved power grid that favours top-down energy distribution from a backbone of large power plants to widespread consumers. Now, with the increase of energy production in lower layers of the grid, there is also a bottom-up flow of the grid infrastructure compromising its stability. In order to locally adapt the energy deman…
Strategies and Techniques for Powering Wireless Sensor Nodes through Energy Harvesting and Wireless Power Transfer
2019
The continuous development of internet of things (IoT) infrastructure and applications is paving the way for advanced and innovative ideas and solutions, some of which are pushing the limits of state-of-the-art technology. The increasing demand for Wireless Sensor Nodes (WSNs) able to collect and transmit data through wireless communication channels, while often positioned in locations that are difficult to access, is driving research into innovative solutions involving energy harvesting (EH) and wireless power transfer (WPT) to eventually allow battery-free sensor nodes. Due to the pervasiveness of radio frequency (RF) energy, RF EH and WPT are key technologies with the potential to power …
Integration of distributed energy systems in micro-grid architecture for making a virtual power plant
2015
This paper presents a novel concept for increasing the penetration level of distributed renewable energy systems into the main electricity grid. When increasing the renewable energy penetration, it is important to implement the frequency based power delivery in distributed generators and work as traditional synchronous generators. This can be achieved by improving the power processing unit of each renewable generation units to work as active generators. But in existing grid architecture, the grid frequency is controlled as one common variable over the electricity grid. With such a method, it is difficult to use frequency based power sharing in small distributed generators and participate in…