473 research outputs found
Calculating the inherent visual structure of a landscape (inherent viewshed) using high-throughput computing
This paper describes a method of calculating the inherent visibility at all locations in a landscape (‘total viewshed’) by making use of redundant computer cycles. This approach uses a simplified viewshed program that is suitable for use within a distributed environment, in this case managed by the Condor system. Distributing the calculation in this way reduced the calculation time of our example from an estimated 34 days to slightly over 25 hours using a cluster of 43 workstations. Finally, we discuss the example ‘total viewshed’ raster for the Avebury region, and briefly highlight some of its implications
"Self pop-out”: agency enhances self-recognition in visual search
In real-life situations, we are often required to recognize our own movements among movements originating from other people. In social situations, these movements are often correlated (for example, when dancing or walking with others) adding considerable difficulty to self-recognition. Studies from visual search have shown that visual attention can selectively highlight specific features to make them more salient. Here, we used a novel visual search task employing virtual reality and motion tracking to test whether visual attention can use efferent information to enhance self-recognition of one's movements among four or six moving avatars. Active movements compared to passive movements allowed faster recognition of the avatar moving like the subject. Critically, search slopes were flat for the active condition but increased for passive movements, suggesting efficient search for active movements. In a second experiment, we tested the effects of using the participants' own movements temporally delayed as distractors in a self-recognition discrimination task. We replicated the results of the first experiment with more rapid self-recognition during active trials. Importantly, temporally delayed distractors increased reaction times despite being more perceptually different than the spatial distractors. The findings demonstrate the importance of agency in self-recognition and self-other discrimination from movement in social setting
Integrated Optical Interferometric Biosensors based on Microelectronics technology for biosensing applications
6 páginas, 8 figuras.-- Comunicación oral presentada al Ibersensors´2002 celebrado en Lima (Perú) en 2002.Integrated optical sensors have reached a great importance during last years since they can be used for the direct detection of biomolecular interactions. Moreover, Silicon microelectronics technology allows mass production as well as the fabrication of microsystems by hybrid integration of sources, sensors, photodelectors and CMOS electronics. For the fabrication of an evanescent field sensor with an integrated Mach-Zehnder interferometric (MZI) configuration, the optical waveguides must verify two main characteristics: monomode behaviour and high surface sensitivity. In this paper we present the development of a MZI sensor based on two different optical waveguides: TIR (Total Internal Reflection) and ARROW (Antiresonant Reflecting Optical Waveguides). The advantages of both structures are discussed and experimental results of the devices are
presented.Peer reviewe
Detección de la inespecificidad de un anticuerpo policlonal contra la lipoproteína lipasa mediante herramientas Proteómicas
La lipoproteína lipasa de rata se nitra in vivo en respuesta a la administración de lipopolisacárido
Comunicaciones a congreso
UV laser-induced high resolution cleaving of Si wafers for micro-nano devices and polymeric waveguide characterization
In this work we propose a method for cleaving silicon-based photonic chips by using a laser based micromachining system, consisting of a ND:YVO4laser emitting at 355 nm in nanosecond pulse regime and a micropositioning system. The laser makes grooved marks placed at the desired locations and directions where cleaves have to be initiated, and after several processing steps, a crack appears and propagate along the crystallographic planes of the silicon wafer. This allows cleavage of the chips automatically and with high positioning accuracy, and provides polished vertical facets with better quality than the obtained with other cleaving process, which eases the optical characterization of photonic devices.
This method has been found to be particularly useful when cleaving small-sized chips, where manual cleaving is hard to perform; and also for polymeric waveguides, whose facets get damaged or even destroyed with polishing or manual cleaving processing. Influence of length of the grooved line and speed of processing is studied for a variety of silicon chips. An application for cleaving and characterizing sol–gel waveguides is presented. The total amount of light coupled is higher than when using any other procedure
Nanoscale imaging of buried topological defects with quantitative X-ray magnetic microscopy
This work is licensed under a Creative Commons Attribution 4.0
International License.-- et al.Advances in nanoscale magnetism increasingly require characterization tools providing detailed descriptions of magnetic configurations. Magnetic transmission X-ray microscopy produces element specific magnetic domain images with nanometric lateral resolution in films up to ∼100 nm thick. Here we present an imaging method using the angular dependence of magnetic contrast in a series of high resolution transmission X-ray microscopy images to obtain quantitative descriptions of the magnetization (canting angles relative to surface normal and sense). This method is applied to 55-120 nm thick ferromagnetic NdCo 5 layers (canting angles between 65° and 22°), and to a NdCo 5 film covered with permalloy. Interestingly, permalloy induces a 43° rotation of Co magnetization towards surface normal. Our method allows identifying complex topological defects (merons or 1/2 skyrmions) in a NdCo 5 film that are only partially replicated by the permalloy overlayer. These results open possibilities for the characterization of deeply buried magnetic topological defects, nanostructures and devices.Work supported by Spanish MINECO under grant FIS2013-45469. A. Hierro-Rodriguez acknowledges support from FCT of Portugal (Grant SFRH/BPD/90471/2012). C. Blanco-Roldán thanks support from CSIC JAE Predoc Program.Peer Reviewe
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