Estimating rainfall erosivity from daily precipitation records: a comparison among methods using data from the Ebro Basin (NE Spain)

Among the major factors controlling soil erosion, as vegetation cover or soil erodibility, rainfall erosivity has a paramount importance since it is difficult to predict and control by humans. Accurate estimation of rainfall erosivity requires continuous rainfall data; however, such data rarely demonstrate good spatial and temporal coverage. Daily weather records are now commonly available, providing good coverage that better represents rainfall intensity behavior than do more aggregated rainfall data. In the present study annual rainfall erosivity was estimated from daily rainfall records, and compared to data obtained employing the RUSLE R factor procedure. A spatially-dense precipitation database of high temporal resolution (15 min) was used. Two methodologies were applied: (i) daily rainfall erosivity estimated using several parametric models, and, (ii) annual rainfall erosivity estimated by regression-based techniques employing several intensity precipitation indices and the modified Fournier index. To determine the accuracy of estimates, several goodness-of-fit and error statistics were computed in addition to a spatial distribution comparison. The daily rainfall erosivity models accurately predicted annual rainfall erosivity. Parametric models with few combined parameters and a periodic function simulating intra-annual rainfall behavior provided the best results. Where daily rainfall records were not available, good estimates of annual rainfall erosivity were also obtained using regression-based techniques based on 5-day maximum precipitation events, the maximum wet spell duration, and the ratio between the lengths of average wet and dry spells. Inherent limitations remain in the use of daily weather records for estimating rainfall erosivity. Future research should focus on incorporating measures of natural rainfall properties of the particular region, including kinetic energy and intensity, and their effects on the soil.We thank the Ebro River Hydrographical Confederation (Confederación Hidrográfica del Ebro; CHE) for providing the data used in this study. The research of M.A. was supported by a JAE-Predoc Research Grant from the Spanish National Research Council (Consejo Superior de Investigaciones Científicas; CSIC).Peer reviewe

Grounding systems for power supply facilities

This study aims to define some recommendations for choice of grounding system type for power supply facility. Operating modes of 0.4 kV networks approved by International Electrotechnical Commission (IEC) were considered and their advantages and disadvantages were identified. The comparison criteria were based on the conditions of human safety from electric shock in the breakdown of insulation on the body of electrical equipment, possibilities of expanding the network and uninterruptible power supply. The real application of the neutral modes and the possibility of installing protective devices were also taken into account. All the recommendations made is planned to apply for the modernization of the urban networks and the calculation of the earthing arrangement by using special software

The Trajectory Model for Track Fitting and Alignment

This note introduces the concept of Trajectories. The LHCb trajectory model and the implementation in the track fitting and tracking sub-detector code as in Brunel v31r2 are described. The possible use of trajectories for alignment is outlined

Design of a robotic hand with a biologically-inspired parallel actuation system for prosthetic applications

Trabajo presentado al 34th Annual Mechanisms and Robotics Conference celebrado en Quebec del 15 al 18 de agosto de 2010.This paper presents the design of a robotic hand for prosthetic applications. The main characteristic of this robotic hand is its biologically-inspired parallel actuation system, which is based on the behavior/strength space of the Flexor Digitorum Profundus (FDP) and the Flexor Digitorum Superficialis (FDS) muscles. The design separates the strength space of the FDS and FDP muscles into a lighter strength region where finer manipulation and general approach tasks are executed, and a higher strength region where the more robust grasps are achieved. Two parallel actuator types and kinematic structures are designed to complement the requirements of both strength space regions.This research was performed under an award/contract from Telemedicine Advanced Technology Research Center (TATRC), of the U.S. Army Medical Research and Materiel Command (USAMRMC) of the U.S. Department of Defense.Peer Reviewe

All-inorganic core-shell silica-titania mesoporous colloidal nanoparticles showing orthogonal functionality

Colloidal mesoporous silica (CMS) nanoparticles with a thin titania-enriched outer shell showing a spatially resolved functionality were synthesized by a delayed co-condensation approach. The titaniashell can serve as a selective nucleation site for the growth of nanocrystalline anatase clusters. These fully inorganic pure silica-core titania-enriched shell mesoporous nanoparticles show orthogonal functionality, demonstrated through the selective adsorption of a carboxylate-containing ruthenium N3-dye. UV-Vis and fluorescence spectroscopy indicate the strong interaction of the N3-dye with the titania-phase at the outer shell of the CMS nanoparticles. In particular, this interaction and thus the selective functionalization are greatly enhanced when anatase nanocrystallites are nucleated at the titania-enriched shell surface

INFLUENCE OF LINEAR ALKYLBENZENE SULFONATE (LAS) AS ORGANIC COSOLVENT ON LEACHING BEHAVIOR OF PCDD/FS FROM FLY-ASH AND SOIL

The leaching of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) was measured in soil and standard fly ash column eluted with pure water and linear alkylbenzene sulfonate (LAS)- water. The data obtained were used to evaluate the leachability of PCDD/Fs from waste dump like incineration residual slag and fly ash deposition. The leaching rate was shown to be increased significantly by using LAS water. The leachate contents of PCDD/Fs were above their known water solubility. Concentration of PCDD/Fs in the leachates as well as the relative leaching (calculated on the fly ash content) increased with increasing chlorinating degree and decreasing water solubility. LAS above the critical micelle concentration (CMC) probably enhances PCDD/Fs solubility