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Seismic testing of large-size models is nowadays possible thanks to the pseudodynamic (PsD) method, which resembles a quasi-static method with the application of slowly varying forces to the test structure. Low testing velocity may change the behaviour of the materials with respect to their behaviour at real velocity due to strain rate effect (SRE). The SRE during a PsD test is not relevant for the classical construction materials. However, it can be very important for some new materials, such as rubber or silicon, mostly used in isolators or energy dissipative devices. Silicone fluid viscous dampers are an example of these dissipative devices, and they will be the subject of this paper. It is possible to extend the PsD method range of application to structures equipped with dissipative devices by introducing a correction technique (CT) developed by the European Laboratory for Structural Assessment (European Commission) in Ispra, Italy. This technique consists of an on-line linear modification of the restoring measured forces. In this paper, two new procedures of CT are proposed. The first procedure consists of a linear filter where the output is the corrected force and the inputs are the measured forces and displacements. The second procedure is based on neural networks, using the same input but adding the test velocity rate. First, the most appropriate scheme of the algorithms was selected and calibrated. This is based on experimental data obtained by dynamically testing the dissipation devices with a displacement pattern, which was specifically designed for this purpose, at different frequencies and test velocities. Then, the capability of the obtained filter/net is tested using experimental data. Additionally, the most appropriate frequency for the training tests was studied. Outcomes were successful. Both algorithms outperform the previous linear CT, the net-based one being the most accurate and versatile. It was found that the first natural frequency of the un

El proyecto busca aplicar la ruta hacia la eficiencia administrativa y financiera, estableciendo planes que permitan al gerente identificar las actividades, los responsables, los tiempos, los costos y los beneficios estimados para alcanzar el estadio II definido por el Modelo de modernización para la gestión de organización MMGO de la EAN en la empresa Cavalco; con el fin de crear una PYME innovadora capaz de integrar los procesos con los proveedores, clientes internos y externos para agregar valor, satisfaciendo a sus grupos de interés (stakeholders) en un tiempo muy corto.

La distribución de la riqueza se representa en forma de pirámide, donde en la parte superior está formada por solo el 20% de la población, y en la base el 80% restante vive con menos de dos dólares al día. En este trabajo analizo cómo se pueden crear negocios en la base de la pirámide, a través del análisis del mercado, su desarrollo y la cadena de valor. El principal objetivo del estudio es profundizar en el concepto y las características de la Base de la Pirámide, así como la inserción de negocios inclusivos en este mercado. Esta metodología la aplico a través de nueve experiencias empresariales, que han contribuido a mejorar las condiciones de vida de la población con bajos ingresos. Demostrar que las empresas pueden tener la oportunidad de hacer negocios en este mercado y de esta manera aliviar la pobreza

This work summarizes the observations made on the variation and time evolution of the reflectanceanisotropy signal during the MOVPE growth of GaInPnucleation layers on Germanium substrates. This in situ monitoring tool is used to assess the impact of different nucleation routines and reactor conditions on the quality of the layers grown. This comparison is carried out by establishing a correlation between reflectanceanisotropy signature at 2.1 eV and the morphology of the epilayers evaluated by atomic force microscopy (AFM). This paper outlines the potential of reflectanceanisotropy to predict, explore, and therefore optimize, the best growth conditions that lead to a high quality III–V epilayer on a Ge substrate

V(D)J recombination is the assembly of gene segments at the antigen receptor loci to generate antigen receptor diversity in T and B lymphocytes. This process is regulated, according to defined developmental programs, by the action of a single specific recombinase complex formed by the recombination antigen gene (RAG-1/2) proteins that are expressed in immature lymphocytes. V(D)J recombination is strictly controlled by RAG-1/2 accessibility to specific recombination signal sequences in chromatin at several levels: cellular lineage, temporal regulation, gene segment order, and allelic exclusion. DNA cleavage by RAG-1/2 is regulated by the chromatin structure, transcriptional elongation, and three-dimensional architecture and position of the antigen receptor loci in the nucleus. Cis-elements specifically direct transcription and V(D)J recombination at these loci through interactions with transacting factors that form molecular machines that mediate a sequence of structural events. These events open chromatin to activate transcriptional elongation and to permit the access of RAG-1/2 to their recombination signal sequences to drive the juxtaposition of the V, D, and J segments and the recombination reaction itself. This chapter summarizes the advances in this area and the important role of the structure and position of antigen receptor loci within the nucleus to control this process.

In this work the authors present an electrical characterization of the so called arrowhead defects (ADs) in GaInP thin films grown on Ge(100) substrates misoriented by 6° toward (111). The samples have been evaluated by means of conductive atomic force microscopy (C-AFM) and Kelvin probe force microscopy (KPFM). It is shown that the ADs have terminating planes which are composed from two alternating subplanes inclined 12° (close to {105} plane) and 6° (close to {109}) with respect to the (100) plane. The terminating planes of the arrowhead defects possess higher conductivity compared to their surrounding. The terminating planes differ also in their electrical behavior from each other, demonstrating different values of conductivity (C-AFM) and bucking voltages (KPFM). The difference in current densities between two terminating planes was found to be ∼ 170±35 μA/m2 at −3 V, and the difference in the bucking voltages was ∼ 70 mV at 5 V of the electrical excitation signal in the lift mode. It is suggested that the distinctive electrical behavior of the ADs is caused by an ordering effect which leads in this case to the degraded electrical properties of the ADs.

One of the classical applications of the SMA is based on the used of the hysteresis cycle associated to the martensitic transformation (classically, described as a first order phase transition) for damping devices. For each application a detailed knowledge of the conditions to be accomplished by the material is absolutely necessary. For the stayed cables in bridges of the Iroise bridge, the oscillation frequencies are 1 and 3 Hz; and the peak to peak oscillation amplitude is close to 10 cm and, also, the SMA works in close contact with the external ambient temperature. In fact, the bridge is a 2*2 lanes free highway situated between Brest and Plougastel (France). The main requirement is related to several days of intense winds or rain associated to strong storms. The conditions imposed to the samples suggest appropriate behavior for, at least, 500000 cycles of working. The experimental analysis, centered in NiTi, is focused in 1) the fatigue life of the samples, 2) the evaluation of the Clausius-Clapeyron coefficient, 3) assuring that the degradation of the material properties remains below a safety limit in the expected time scale of application, 4) modeling the cable behavior to show the positive damping capacity of SMA and 5) studying the applications in semi-realistic scale in the ELSA-JRC (a civil engineering facility in Ispra, Italy) demonstrating the positive effect of the SMA.

A barrier based on GaAs for controlling the Ge out diffusion has been developed by metalorganic vapor phase epitaxy. It is based on a thin GaAs layer (50 nm) grown at a low temperature (≈500 °C) on top of a predeposition layer, showing that GaAs prevents the Ge diffusing when it is grown at a low temperature. Additionally, two different predeposition monolayers have been compared, concluding that when the Ga is deposited first, the diffusions across the GaAsGe heterointerface decrease.

Frequently,whengrowing III–V semiconductors on germanium substrates, unexpected differences between nominally identical substrates are encountered. Using atomic force microscopy (AFM), we have analysed a set of germanium substrates sharing the same specifications.The substrates come from the same vendor but different results come about in terms of the morphology of the epilayers produced by the same epitaxial routine(i.e. substrateW1 produce depilayers with good morphology while substrate WX produce depilayers with defects). The morphological analysis has been carried out on(a)epiready substrates; (b)samples after a high-temperature bake at 700 1C; and(c)on the samples after a hydride (PH3) annealingat640 1C. In the two first stages all substrates(both W1 and WX) show the same good morphology with RMS roughness below A˚ in all cases. It is in the third stage(annealinginPH3) that the morphology degrades and the differences between the samples become apparent. After phosphine exposureat640 1C, the RMS roughness of both substrates approximately doubles, and their surface appears as full of peaks and valleys on the nanometer scale. Despite the general appearance of the samples being similar, a careful analysis of their surface reveals that the substrates that produce bad morphologies(WX) show higher peaks, and some of their roughness parameters, namely, surface kurtosis and the surface skewness, are considerably degraded.

The measurement of the dark I–V curve is one of the most straightforward methods for characterizing solar cells. Consequently, an accurate knowledge of its meaning is of high relevance for the comprehension and technological feedback of these devices. In this paper, an explanation of the dark I–V curve for concentrator III–V solar cells is presented using a 3D (three-dimensional) model in order to provide a proper data fit that provides meaningful physical parameters that are also compatible and coherent with a data fit from illumination curves. The influence on the dark I–V curve of the most significant series resistance components of concentrator solar cells is also analysed concluding that only the vertical component as well as the front contact-specific resistance can be assessable by means of this characterization method while both emitter and metal sheet resistances cannot be detected. For comparison purposes, the same experimental data have been fitted by means of a traditional two-diode model showing that, although an accurate dark I–V curve fitting can be achieved, the extracted parameters are unable to reproduce illumination data since lumped models assume the same ohmic losses distribution for both dark and illumination conditions.

The European Laboratory for Structural Assessment (ELSA) belongs to the Joint Research Centre (JRC) of the European Commission. It is one of the units of the Institute for the Protection and Security of the Citizen (IPSC) at the Ispra Site of the JRC. The main facility of ELSA is a large Reaction Wall‐Strong Floor system equipped with powerful servoactuators used to simulate the response of civil full‐size structures submitted to dynamic loads using the ELSAPSD testing system. During a test, the user may want some data to be displayed, analyzed or/and stored in the computer. This can be made through an acquisition object. This manual explains how to use an acquisition starting from the most simple case, which is using an acquisition node with an internal trigger. Each chapter adds new information to the previous one, so it is interesting to read the manual in a sequential order. This manuals refers to the acquisition software of ELSAPSD according to the versions PSDCYC03.DLL and M13.004 of the master controller software and acqui.exe???????.

A DLL (Dynamic Link Library) is a file of code containing functions that can be called from other executable code. The advantage of working with DLLs at ELSA PsD Master controller is in the modularity for programming the testing method and algorithm without the need to work with the master.exe program. This new version of DLL allows the implementation of both PsD and Cyclic test, plus strain-rate effect compensation, re-start capabilities and a large variety of security alarms. In this manual the user will find a full explanation of how to use the DLL throughout some simple examples. Some other examples coming from real tests carried out at ELSA laboratory can be found in the Annex.

Content and/or metadata distribution is a key factor in order to foster knowledge sharing in virtual learning communities. This article presents a solution based on web services for providing this kind of distribution. Starting from the pedagogical requirements of a community that needs to share resources generated in different scientific/technical thematic scenarios, a solution is proposed to fit these requirements. Several technological options are presented as well as the chosen design, that merges interoperability and flexibility for adapting to different configurations., La distribución de contenidos y/o metadatos en Repositorios de Objetos de Aprendizaje es un aspecto clave a la hora de favorecer el intercambio de conocimiento dentro de comunidades de aprendizaje. En este artículo se presenta una solución basada en servicios web para ofrecer esta distribución. Partiendo del análisis de las necesidades de una comunidad para compartir recursos generados en distintos escenarios temáticos científico-técnicos, se propone una solución que cumple sus requisitos pedagógicos. Se discuten las distintas opciones tecnológicas disponibles y se presenta el diseño realizado, que se caracteriza además por ofrecer interoperabilidad y flexibilidad para adaptar la configuración a diferentes situaciones.