Evaluation of an offshore wind farm computational fluid dynamics model against operational site data

Modelling wind turbine wake effects at a range of wind speeds and directions with actuator disk (AD) models can provide insight but also be challenging. With any model it is important to quantify the level of error, but this can also present a challenge when comparing a steady-state model to measurement data with scatter. This paper models wind flow in a wind farm at a range of wind speeds and directions using an AD implementation. The results from these models are compared to data collected from the actual farm being modelled. An extensive comparison is conducted, constituted from 35 cases where two turbulence models, the standard k-ε and k-ω SST are evaluated. The steps taken in building the models as well as processes for comparing the AD computational fluid dynamics (CFD) results to real-world data using the regression models of ensemble bagging and Gaussian process are outlined. Turbine performance data and boundary conditions are determined using the site data. Modifications to an existing opensource AD code are shown so that the predetermined turbine performance can be implemented into the CFD model. Steady state solutions are obtained with the OpenFOAM CFD solver. Results are compared in terms of velocity deficit at the measurement locations. Using the standard k-ε model, a mean absolute error for all cases together of roughly 8% can be achieved, but this error changes for different directions and methods of evaluating it

Electropolymerized polypyrrole silver nanocomposite coatings on porous Ti substrates with enhanced corrosion and antibacterial behavior for biomedical applications

Producción CientíficaThis work proposes an innovative strategy that combines two well-known easy and economical preparation techniques: powder metallurgy based space-holder (SH) technique to provide porous biocompatible Ti substrates with balanced biomechanical behavior (for cortical bone tissue substitution) promoting bone ingrowth and biocoating infiltration, and electropolymerization to coat these substrates with the polypyrrole–silver nanoparticles (PPy-AgNPs) composite conductive polymers improving its corrosion resistance, biocompatibility with enhanced antibacterial activity. The deposited PPy-based coatings present a cauliflower-like structure well adhered to the porous substrates. The macroporosity of and rough inner pore surface of Ti SH substrates are responsible for the superior adhesion of the conductive polymer comparing to typical denser substrates obtained by powder metallurgy or forging. The corrosion protection properties of the coatings were investigated by open circuit potential and Anodic Polarization in PBS media to simulate possible implant conditions, revealing improved corrosion resistance for the composite coatings. The bioactivity of the coatings was evaluated by immersion tests, revealing the formation of Hydroxyapatite after 90-day immersion in PBS. In both PPy and PPy-AgNPs composite coatings, a displacement of the polarization curves to more noble potentials and a decrease in the current density, indicated that the coating's protective character is maintained after 90-day immersion in PBS. The antibacterial activity was assessed by using the Kirby–Bauer disk-diffusion method against Staphylococcus aureus (ATCC 25923). The inhibition halo increased from 5.5 ± 0.4 mm for the bare substrate to 8.2 ± 0.6 mm for the PPy-coated substrate and to 12.5 ± 0.7 mm for the PPy-AgNPs-coated porous Ti. This feature associated to the improved corrosion protection and biocompatibility would significantly contribute to the success of the potential use of porous Ti implants by SH technique envisaging substitution of small damaged bone tissues for example in tumors.Ministerio de Ciencia e Innovación (RTI2018-097990-B-I00 y PID2019-109371 GB-I00)Junta de Andalucía–FEDER (US-1259771)Junta de Castilla y León (VA275P18 y VA044G19

Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): Border disease

Non peer reviewe

Engineering Mycobacterium smegmatis for testosterone production

11 p.-8 fig.-1 tab.A new biotechnological process for the production of testosterone (TS) has been developed to turn the model strain Mycobacterium smegmatis suitable for TS production to compete with the current chemical synthesis procedures. We have cloned and overexpressed two genes encoding microbial 17b-hydroxysteroid: NADP 17-oxidoreductase, from the bacterium Comamonas testosteroni and from the fungus Cochliobolus lunatus.The host strains were M. smegmatis wild type and a genetic engineered androst-4-ene-3,17-dione (AD) producing mutant. The performances of the four recombinant bacterial strains have been tested both in growing and resting-cell conditions using natural sterols and AD as substrates respectively. These strains were able to produce TS from sterols or AD with high yields. This work represents a proof of concept of the possibilities that offers this model bacterium for the production of pharmaceutical steroids using metabolic engineering approaches.This work was supported by grants from the Ministry of Science and Innovation (BFU2006-15214-C03-01,BFU2009-11545-C03-03) and Ministry of Economy and Competitiveness (BIO2012-39695-C02-01).Peer reviewe

“Mam” and “Guepy”: Two Valley Zapotec poems

This work consists of two poems written in San Lucas Quiaviní Zapotec, a Valley Zapotec language spoken in the state of Oaxaca, Mexico. The poems are presented with English and Spanish translations, notes about the poet and translator, explanation of the translation process, and culture information

After the 2015 Paris Attacks: British Muslims seen by the British written media

Desde los atentados terroristas del 11 de Septiembre de 2001, el terrorismo parece estar más presente que nunca en el mundo Occidental. Así, los atentados de París que tuvieron lugar el 13 de Noviembre de 2015 sólo contribuyeron a empeorar esta situación, convirtiéndose en uno de los puntos de inflexión del siglo XXI y sembrando el pánico en los países Occidentales. En este trabajo de fin de grado, propongo un análisis exhaustivo de artículos publicados en distintos periódicos del Reino Unido. Se pretende mostrar cómo los diferentes periódicos, independientemente de su ideología o calidad, han reflejado la imagen de los Musulmanes Británicos, relacionándolos con diferentes estereotipos negativos

Trip distribution model for regional railway services considering spatial effects between stations

The railways are a priority transport mode for the European Union given their safety record and environmental sustainability. Therefore it is important to have quantitative models available which allow passenger demand for rail travel to be simulated for planning purposes and to evaluate different policies. The aim of this article is to specify and estimate trip distribution models between railway stations by considering the most influential demand variables. Two types of models were estimated: Poisson regression and gravity. The input data were the ticket sales and the prices between stations on a regional line in Cantabria (Spain) which were provided by the Spanish railway infrastructure administrator (ADIF – RAM). The models have also considered the possible existence of spatial effects between train stations. The results show that the models have a good fit to the available data, especially the gravity models constrained by origins and destinations. Furthermore, the gravity models which considered the existence of spatial effects between stations had a significantly better fit and provided a more realistic journey pattern in a future scenario than the Poisson models and the gravity models that did not consider these effects. The proposed models have therefore been shown to be good support tools for decision making in the field of railway planning.This research was made possible thanks to financing from the Horizon 2020 Framework Programme, Shift2Rail Joint Undertaking 2015 call through the "NEAR2050: future challenges for the rail sector" project (Grant Number: 730838). The authors would also like to thank ADIF – RAM for having provided the data used

Avellanado conico y cilindrico

Décimo tercera cartilla del “Curso de maquinas y herramientas” que contiene las hojas de tarea, información tecnológica y operación donde se describe qué son las fresas de avellanar y rebajar, sus características, avellanado cónico y avellanar cilíndrico.Thirteen third booklet of the "Course of machines and tools" that contains the task sheets, technological information and operation where it describes what are the countersink and reduce milling cutters, their characteristics, countersunk conical and countersunk cylindrical.Avellanado cónico y avellanado cilíndrico -- Fresas de avellanar y rebajar -- Avellanar conico -- Avellanar cilíndricona9 página