865 resultados para SATURABLE-ABSORBER MIRROR
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Resumen: Este trabajo busca demostrar cómo la escena de “El Jardín de Isabel” (acto IV, escena ii) en la obra La tragedia española de Thomas Kyd es un ejemplo de una escena espejo. Inicialmente se observa cómo esta escena está laxamente conectada con el resto de la obra y la misma no sufriría un cambio significativo de ser la escena eliminada; la característica de “prescindible” de ésta, es propia de una escena espejo. La escena del Jardín de Isabel es luego estudiada en profundidad para dejar en evidencia cómo resume la obra y la simboliza. El personaje de Isabel es examinado en detalle, siguiendo una sensibilidad pictórica y, a través de una interpretación temática y simbólica, Isabel es presentada como Piedad, Testigo de Justicia Divina y Venganza. Finalmente el espacio es también analizado como locus amoenus al ser inicialmente un lugar de encuentro de los enamorados y locus eremus luego de la maldición de Isabel. Luego del estudio de estos aspectos de esta escena espejo, se pone en evidencia cómo la misma “refleja” los temas centrales de la obra: la verdad se revela con el tiempo, hay que ser paciente y esperar la justicia divina y, por último, la venganza sólo condena al vengador.
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The instability of the crack tip in brittle Mg-based bulk metallic glass (BMG) is studied. The formation of various fractographic surfaces of the BMG is associated with the instability of the fluid meniscus, which is due to viscous fluid matter being present on the fracture process zone. Depending on the values of the wavelength of the initial perturbation of the fluid meniscus and the local stress intensity factor, different fracture surface profiles, i.e. a dimple-like structure, a periodic corrugation pattern and a pure mirror zone are formed. The fractographic evolution is significantly affected by the applied stress. A decreased fracture Surface roughness is observed under a low applied stress. An increased fracture surface roughness, which has frequently been reported by other researchers, is also observed in the present studies under a high applied stress. Unique fractographic features are attributed to the non-linear hyperelastic stiffening for less softening) mechanism. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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The self-assembling process near the three-phase contact line of air, water and vertical substrate is widely used to produce various kinds of nanostructured materials and devices. We perform an in-situ observation on the self-assembling process in the vicinity of the three phase contact line. Three kinds of aggregations, i.e. particle-particle aggregation, particle-chain aggregation and chain-chain aggregation, in the initial stage of vertical deposition process are revealed by our experiments. It is found that the particle particle aggregation and the particle-chain aggregation can be qualitatively explained by the theory of the capillary immersion force and mirror image force, while the chain-chain aggregation leaves an opening question for the further studies. The present study may provide more deep insight into the self-assembling process of colloidal particles.
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We report an unusual transition from a locally ductile to a pure brittle fracture in the dynamic fracture of brittle Mg65Cu20Gd10 bulk metallic glass. The fractographic evolution from a dimple structure to a periodic corrugation pattern and then to the mirror zone along the crack propagation direction during the dynamic fracture process is discussed within the framework of the meniscus instability of the fracture process zone. This work might provide an important clue in understanding of the energy dissipation mechanism for dynamic crack propagation in brittle glassy materials. (C) 2008 American Institute of Physics.
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Results observed experimentally are presented, about the DC arc plasma jets and their arc-root behaviour generated at reduced gas pressure without or with an applied magnetic field. Pure argon, argon-hydrogen or argon- nitrogen mixture was used as the plasma-forming gas. A specially designed copper mirror was used for a better observation of the arc-root behaviour on the anode surface of the DC non-transferred arc plasma torch. It was found that in the cases without an applied magnetic field, the laminar plasma jets were stable and approximately axisymmetrical. The arc-root attachment on the anode surface was completely diffusive when argon was used as the plasma-forming gas, while the arc-root attachment often became constrictive when hydrogen or nitrogen was added into the argon. As an external magnetic field was applied, the arc root tended to rotate along the anode surface of the non-transferred arc plasma torch.
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Resumen: Incluso antes de su llegada al trono, Alfonso X (1252-1284) emprendió una amplia labor de recopilación, traducción y reescritura de obras, tanto jurídicas, históricas como científicas. Numerosos estudios han subrayado tanto la coherencia de este proyecto como su funcionalidad política, en la medida en que dibuja un nuevo marco de relaciones en el reino y en la corte. En este trabajo, basado en la producción historiográfica y en parte de las obras científicas elaboradas en el scriptorium de Alfonso X, se intentará mostrar que esta producción textual supone una renovación, no sólo en el ámbito político sino también discursivo, y no sólo por la ruptura que supone la utilización del castellano. El análisis de prácticas tales como la compilación, la reescritura y la traducción, que remitirían en principio a una clara continuidad con la tradición textual anterior, permite por el contrario tomar la medida del salto cualitativo que representa la obra alfonsí en cuanto al sentido mismo que se la da a la escritura. La interpretación a la que se pretende llegar es que, si bien los colaboradores regios compilan, reescriben y traducen, la perspectiva desde la que el rey, considerado como autor de las obras, ordena los saberes que estas actividades producen, supone romper con el topos fundador de gran parte de la literatura medieval, la metáfora del espejo, según la cual el libro revela la verdad en la medida en que revela y refleja el mundo, es decir el orden divino
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La pasantía como forma de culminación de estudios es la vinculación del egresado al mundo laboral en función del ejercicio profesional y se orientan al desarrollo de competencias del perfil de la carrera. El período de pasantías se efectuó en El Proyecto Red de Innovación Agrícola (RED SICTA), iniciando de Mayo a Noviembre 2014. Durante este periodo el pasante se enfocó a trabajar en las redes territoriales de innovación (Nueva Segovia y Matagalpa) en gestión del conocimiento y difusión de inoculante para frijol estableciendo que el proyecto está apegado a los siguientes componentes: Componente de desarrollo y gestión de innovaciones tecnológicas a nivel nacional y regional; Productores y productoras centroamericanos participantes en las cadenas de maíz y frijol incorporan innovaciones que mejoran su rentabilidad. Componente de gestión de conocimientos para la innovación. Los miembros de las redes nacionales de las cadenas de maíz y frijol participan activamente en la gestión de conocimientos, mejoran su aprendizaje y hacen aportes a los sistemas nacionales de innovación. El SICTA cuenta con un sistema de intercambio de conocimientos sobre innovaciones e información estratégica en cadenas de maíz y frijol en Centroamérica. Componente de fortalecimiento institucional del Sistema de Integración Centroamericana de Tecnología Agrícola (SICTA).De las funciones desempeñadas en la institución permitió fortalecer conocimientos y destrezas dentro de las cuales señalan las siguientes: Redacción de base de datos de usuarios del proyecto, elaboración de encuestas de caracterización a instituciones asociadas, facilitador de capacitaciones sobre el uso de inoculante en frijol a miembros de la red Matagalpa y Nueva Segovia, redacción de fichas tecnológicas en base a las tecnologías difundidas, seis días de campo en difusión de uso de inoculante en frijol en la comunidad San Pedro Matagalpa y Tataslí Nueva Segovia. Uno de los resultados obtenidos mediante la pasantía, es la colaboración en la difusión de la tecnología inoculante para frijol con cubierta plástica, donde el pasante brindo información de la tecnología a un total de 255 productores que participaron en los seis días de campo realizándose tres por departamento. Como una lección Aprendida de acuerdo a los resultados fue la interacción e intercambio de experiencia con productores mediante días de campo en la presentación de tecnología, teniendo en cuenta que el productor juega un papel muy importante y fundamental ya que son los que deciden si adoptan una tecnología o no. Como conclusión se puede decir que a medida que se va ejecutando la pasantía se hace familiar la labor y se va obteniendo nuevos conocimientos y más ampliados sobre la misma; tratándose de un periodo de nuevas enseñanzas y experiencias que se basan en los conocimientos adquiridos en el aula de clase y con la posibilidad de absorber muchos nuevos. Como una recomendación enfocada a la Universidad es dar mejor seguimiento para los pasantes durante el periodo de pasantías constando en supervisión al pasante.
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[ES] El presente trabajo tiene por objeto llegar a un diagnóstico de la capacidad, por parte de las empresas del Territorio Histórico de Bizkaia, de absorber los resultados de I+D generados por universidades y otros centros de investigación. Para ello, en primer lugar, mediante una revisión de la literatura teórica y empírica existente sobre el tema, se identifican las características empresariales vinculadas a dicha capacidad de absorción; a continuación, se analiza el grado de presencia de tales características en dos muestras de empresas: una muestra de 26 empresas vizcaínas avanzadas en gestión, y una muestra más general de empresas vizcaínas de más de 10 trabajadores; por último, se identifican las características en las que las empresas de Bizkaia manifiestan suficiente capacidad para absorber resultados de I+D externa, frente a aquellas otras que resulta necesario desarrollar, pues en ellas todavía no se han alcanzado niveles satisfactorios.
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Revisions of US macroeconomic data are not white-noise. They are persistent, correlated with real-time data, and with high variability (around 80% of volatility observed in US real-time data). Their business cycle effects are examined in an estimated DSGE model extended with both real-time and final data. After implementing a Bayesian estimation approach, the role of both habit formation and price indexation fall significantly in the extended model. The results show how revision shocks of both output and inflation are expansionary because they occur when real-time published data are too low and the Fed reacts by cutting interest rates. Consumption revisions, by contrast, are countercyclical as consumption habits mirror the observed reduction in real-time consumption. In turn, revisions of the three variables explain 9.3% of changes of output in its long-run variance decomposition.
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Experimentally observed, results are presented for the DCarcplasmajets and theirarc-rootbehaviors generated atreduced gas pressure and without or with an' applied magnetic field. Pure argon, argon -hydrogen or argon-nitrogen mixture is used as the plasma-forming gas. A specially designed copper mirror is constructed and used for better observing the arc-root behavior on the anode surface of the DC non-transferred arcplasma torch. It is shown that for the cases without applied magnetic field, the laminar plasmajets are stable and approximately axisymmetrical. The arc-root attachment on the anode surface is completely diffusive when argon is used as the plasma-forming gas, while the arc-root attachment often becomes constrictive when hydrogen or nitrogen is added into the argon. When an external magnetic field is applied, the arcroot tends to rotate along the anode surface of the non-transferred arcplasma torch.
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It is well-known that cone effect or focus anisoplanatism is produced by the limited distance of a laser guide star (LGS) which is created within the Earth atmosphere and consequently located at a finite distance from the observer. In this paper, the cone effect of the LGS for different vertical profiles of the refractive index structure constant Cn2 is numerically investigated by using a revised computer program of atmospheric propagation of optical wave and an adaptive optics (AO) system including dynamic control process. According to the practice, the overall tilt for the tilt-correction mirror is obtained from a natural star and the aberrated wavefront for phase correction of the deformable mirror is obtained from a LGS in our numerical simulation. It is surprisingly found that the effect of altitude of the LGS on the AO phase compensation effectiveness by using the commonly-available vertical profiles of Cn2 and the lateral wind speed in the atmosphere is relatively weak, and the cone effect for some Cn2 profiles is even negligible. It is found that the cone effect does not have obvious relationship with the turbulence strength, however, it depends on the vertical distribution profile of Cn 2 apparently. On the other hand, the cone effect depends on the vertical distribution of the lateral wind speed as well. In comparison to a longer wavelength, the cone effect becomes more obvious in the case of a shorter wavelength. In all cases concerned in this paper, an AO system by using a sodium guide star has almost same phase compensation effectiveness as that by using the astronomical target itself as a beacon. Effect of dynamic control process in an AO system on the cone effect is studied in this paper for the first time within our knowledge.
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Common carp is one of the most important cultured freshwater fish species in the world. Its production in freshwater areas is the second largest in Europe after rainbow trout. Common carp production in Europe was 146,845 t in 2004 (FAO Fishstat Plus 2006). Common carp production is concentrated mainly in Central and Eastern Europe. In Hungary, common carp has been traditionally cultured in earthen ponds since the late 19th century, following the sharp drop in catches from natural waters, due to the regulation of main river systems. Different production technologies and unintentional selection methods resulted in a wide variety of this species. Just before the intensification of rearing technology and the exchange of stocking materials among fish farms (early sixties), “landraces” of carp were collected from practically all Hungarian fish farms into a live gene bank at the Research Institute for Fisheries, Aquaculture and Irrigation (HAKI) at Szarvas (Bakos and Gorda 1995; Bakos and Gorda 2001). In order to provide highly productive hybrids for production purposes starting from 1964, different strains and crosses between Hungarian landraces were created and tested. During the last 40 years, approximately 150 two-, three-, and four-line hybrids were produced. While developing parental lines, methods of individual selection, inbreeding, backcrossing of lines, gynogenesis and sex reversal were used. This breeding program resulted in three outstanding hybrids: “Szarvas 215 mirror” and “Szarvas P31 scaly” for pond production, and “Szarvas P34 scaly” for angling waters. Besides satisfying the needs of industry, the live gene bank helped to conserve the biological diversity of Hungarian carp landraces. Fifteen Hungarian carp landraces are still maintained today in the gene bank. Through exchange programs fifteen foreign carp strains were added to the collection from Central and Eastern Europe, as well as Southeast Asia (Bakos and Gorda 2001). Besides developing the methodology to maintain live specimens in the gene bank, the National Carp Breeding Program has been initiated in cooperation with all the key stakeholders in Hungary, namely the National Association of Fish Producers (HOSZ), the National Institute for Agricultural Quality Control (OMMI), and the Research Institute for Fisheries, Aquaculture and Irrigation (HAKI). In addition, methodologies or technologies for broodstock management and carp performance testing have been developed. This National Carp Breeding Program is being implemented successfully since the mid-1990s.
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After stroke, white matter integrity can be affected both locally and distally to the primary lesion location. It has been shown that tract disruption in mirror's regions of the contralateral hemisphere is associated with degree of functional impairment. Fourteen patients suffering right hemispheric focal stroke (S) and eighteen healthy controls (HC) underwent Diffusion Weighted Imaging (DWI) and neuropsychological assessment. The stroke patient group was divided into poor (SP; n = 8) and good (SG; n = 6) cognitive recovery groups according to their cognitive improvement from the acute phase (72 hours after stroke) to the subacute phase (3 months post-stroke). Whole-brain DWI data analysis was performed by computing Diffusion Tensor Imaging (DTI) followed by Tract Based Spatial Statistics (TBSS). Assessment of effects was obtained computing the correlation of the projections on TBSS skeleton of Fractional Anisotropy (FA) and Radial Diffusivity (RD) with cognitive test results. Significant decrease of FA was found only in right brain anatomical areas for the S group when compared to the HC group. Analyzed separately, stroke patients with poor cognitive recovery showed additional significant FA decrease in several left hemisphere regions; whereas SG patients showed significant decrease only in the left genu of corpus callosum when compared to the HC. For the SG group, whole brain analysis revealed significant correlation between the performance in the Semantic Fluency test and the FA in the right hemisphere as well as between the performance in the Grooved Pegboard Test (GPT) and theTrail Making Test-part A and the FA in the left hemisphere. For the SP group, correlation analysis revealed significant correlation between the performance in the GPT and the FA in the right hemisphere. Palabras clave
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Advances in optical techniques have enabled many breakthroughs in biology and medicine. However, light scattering by biological tissues remains a great obstacle, restricting the use of optical methods to thin ex vivo sections or superficial layers in vivo. In this thesis, we present two related methods that overcome the optical depth limit—digital time reversal of ultrasound encoded light (digital TRUE) and time reversal of variance-encoded light (TROVE). These two techniques share the same principle of using acousto-optic beacons for time reversal optical focusing within highly scattering media, like biological tissues. Ultrasound, unlike light, is not significantly scattered in soft biological tissues, allowing for ultrasound focusing. In addition, a fraction of the scattered optical wavefront that passes through the ultrasound focus gets frequency-shifted via the acousto-optic effect, essentially creating a virtual source of frequency-shifted light within the tissue. The scattered ultrasound-tagged wavefront can be selectively measured outside the tissue and time-reversed to converge at the location of the ultrasound focus, enabling optical focusing within deep tissues. In digital TRUE, we time reverse ultrasound-tagged light with an optoelectronic time reversal device (the digital optical phase conjugate mirror, DOPC). The use of the DOPC enables high optical gain, allowing for high intensity optical focusing and focal fluorescence imaging in thick tissues at a lateral resolution of 36 µm by 52 µm. The resolution of the TRUE approach is fundamentally limited to that of the wavelength of ultrasound. The ultrasound focus (~ tens of microns wide) usually contains hundreds to thousands of optical modes, such that the scattered wavefront measured is a linear combination of the contributions of all these optical modes. In TROVE, we make use of our ability to digitally record, analyze and manipulate the scattered wavefront to demix the contributions of these spatial modes using variance encoding. In essence, we encode each spatial mode inside the scattering sample with a unique variance, allowing us to computationally derive the time reversal wavefront that corresponds to a single optical mode. In doing so, we uncouple the system resolution from the size of the ultrasound focus, demonstrating optical focusing and imaging between highly diffusing samples at an unprecedented, speckle-scale lateral resolution of ~ 5 µm. Our methods open up the possibility of fully exploiting the prowess and versatility of biomedical optics in deep tissues.
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In Part I of this thesis, a new magnetic spectrometer experiment which measured the β spectrum of ^(35)S is described. New limits on heavy neutrino emission in nuclear β decay were set, for a heavy neutrino mass range between 12 and 22 keV. In particular, this measurement rejects the hypothesis that a 17 keV neutrino is emitted, with sin^2 θ = 0.0085, at the 6δ statistical level. In addition, an auxiliary experiment was performed, in which an artificial kink was induced in the β spectrum by means of an absorber foil which masked a fraction of the source area. In this measurement, the sensitivity of the magnetic spectrometer to the spectral features of heavy neutrino emission was demonstrated.
In Part II, a measurement of the neutron spallation yield and multiplicity by the Cosmic-ray Underground Background Experiment is described. The production of fast neutrons by muons was investigated at an underground depth of 20 meters water equivalent, with a 200 liter detector filled with 0.09% Gd-loaded liquid scintillator. We measured a neutron production yield of (3.4 ± 0.7) x 10^(-5) neutrons per muon-g/cm^2, in agreement with other experiments. A single-to-double neutron multiplicity ratio of 4:1 was observed. In addition, stopped π^+ decays to µ^+ and then e^+ were observed as was the associated production of pions and neutrons, by the muon spallation interaction. It was seen that practically all of the π^+ produced by muons were also accompanied by at least one neutron. These measurements serve as the basis for neutron background estimates for the San Onofre neutrino detector.