Influence of Nb-doping on the structural and electrical properties of lanthanum molybdates, La5.4MoO11.1

Nowadays, hydrogen is receiving a great deal of attention as an energy carrier. Commonly, it is obtained by hydrocarbons reforming, such as natural gas, coal and biomass. However, the resulting hydrogen needs to be purified to remove by-products and impurities, increasing the production costs. An alternative for hydrogen production is proton-conducting ceramics, where hydrogen separation takes place via a chemical potential gradient across the membrane.1, 2 In this work, Nb-doped La6MoO12--based compounds have been investigated as part of a new family of materials very competitive as SOFC electrolyte and hydrogen separation membranes.3 These materials, La5.4Mo1-xNbxO11.1-x/2 (x = 0.05, 0.10, 0.15 y 0.20) were synthesized by the freeze-drying precursor method and calcination conditions have been optimized to obtain single phases. A complete characterization has been carried out using X-Ray powder diffraction and scanning and transmission electron microscopy. The total conductivity was determined by complex impedance spectroscopy at different atmospheres. Different polymorphs are obtained as a function of the cooling rate and the dopant amount. The samples cooled by quenching are cubic with a fluorite-type structure (Fm3 ̅m) and the ones cooled at 50 y 0.5 ºC•min-1 are rhombohedral (R1 and R2 polymorphs). For niobium contents higher than x = 0.10 the R1 polymorph is stabilised at cooling rates equal or inferior to 50 ºC•min-1. For all three series, the incorporation of niobium into La5.4MoO11.1 increases the conductivity, reaching the best values for x=0.10 and the sample obtained by quenching.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

The moral vision of Luis Buñuel in "Nazarín": An emancipation of galdosian novel

La versión cinematográfica de la novela galdosiana Nazarín, dirigida por Luis Buñuel, afronta la problemática de la adaptación como proceso de traducción de la obra. El trasvase del texto escrito al ámbito de la imagen trae consigo, además de la complejidad estructural inherente a cada medio, los elementos creativos del cineasta insertos en el relato. Las aportaciones de Luis Buñuel a la novela transforman el significado del mensaje y lo llevan hacia una nueva dimensión moral que emancipa al film del texto literarioThe film version of galdosian novel Nazarín, directed by Luis Buñuel, confronts the problem of adaptation as a translation of the work. The transfer of written text to the field of image brings with it, besides the structural complexity inherent in each medium, the creative elements of the filmmaker inserted in the story. Luis Buñuel’s contributions to the novel transform the meaning of the message and lead it to a new moral dimension that emancipates the film from the literary tex

CWDM self-referencing sensor network based on ring resonators in reflective configuration

A new scalable self-referencing sensor network with low insertion losses implemented in Coarse Wavelength Division Multiplexing (CWDM) technology is reported. It allows obtaining remote self-referenced measurements with a full-duplex fibre downlead up to 35 km long, with no need for optical amplification. Fibre Bragg gratings (FBG) are used in order to achieve a reflective configuration, thus increasing the sensitivity of the optical transducers. Low-cost off-the-shelf devices in CWDM technology can be used to implement and scale the network. Ring resonator (RR) based incoherent interferometers at the measuring points are used as selfreferencing technique. A theoretical analysis of power budget of the topology is reported, with a comparison between the proposed network and a conventional star topology. Finally, the new configuration has been experimentally demonstrated.This work has been supported by CICYT:TIC2003-03783, UC3M:FAVICOBIS and CAM:FACTOTEM-CM (S-0505/ESP/000417).Publicad

"Ad conuersionem" : Breve exposición de una investigación en curso

El presente artículo pretende recoger la información facilitada durante la celebración del IV Seminario Internacional Islamolatina sobre el desarrollo de mi investigación respecto a la obra Manuductio ad conuersionem Mahumetanorum de Tirso González de Santalla (1624-1705), objeto de estudio de mi tesis doctoral. De este modo, breve y conciso, realizo un estado de las cuestión en torno al estudio y edición critico-filológica de este trabajo de literatura de controversia interreligiosa, sin pretender llegar a unas reflexiones definitivas.This article aims to collect the information about my developing research in the work Manuductio ad conuersionem Mahumetanorum from Tirso González de Santalla (1624-1705) provided during the VI Seminario Internacional Islamolatina. In this way -short and concise- I do a state of affairs around the study and critic-philological edition of this work of inter-religious controversy literature, without trying to arrive to final reflections

Spatiotemporal Stacked Sequential Learning for Pedestrian Detection

Pedestrian classifiers decide which image windows contain a pedestrian. In practice, such classifiers provide a relatively high response at neighbor windows overlapping a pedestrian, while the responses around potential false positives are expected to be lower. An analogous reasoning applies for image sequences. If there is a pedestrian located within a frame, the same pedestrian is expected to appear close to the same location in neighbor frames. Therefore, such a location has chances of receiving high classification scores during several frames, while false positives are expected to be more spurious. In this paper we propose to exploit such correlations for improving the accuracy of base pedestrian classifiers. In particular, we propose to use two-stage classifiers which not only rely on the image descriptors required by the base classifiers but also on the response of such base classifiers in a given spatiotemporal neighborhood. More specifically, we train pedestrian classifiers using a stacked sequential learning (SSL) paradigm. We use a new pedestrian dataset we have acquired from a car to evaluate our proposal at different frame rates. We also test on a well known dataset: Caltech. The obtained results show that our SSL proposal boosts detection accuracy significantly with a minimal impact on the computational cost. Interestingly, SSL improves more the accuracy at the most dangerous situations, i.e. when a pedestrian is close to the camera.Comment: 8 pages, 5 figure, 1 tabl

Modified gravities and applications

Esta tese de Doutoramento orbita arredor de diversos aspectos, consecuencias e implicacións derivadas de considerar modificación á teoría da Relatividade Xeral presentada en 1915 por Albert Einstein. Se ben a relatividade Xeral segue a ter plena vixencia e é de feito un modelo suficientemente preciso para a escala de ernerxías da mayoría de experimentos onde a forza gravitatoria é relevante, temos indicios na física fundamental que indican que é una teoría incompleta. Un dos xeitos máis inmediatos para contextualizar esta afirmación require a apelación á outra teoría revelación do pasado século XX, a física cuántica. E é que namentras o resto de forzas da natureza si teñen cadansúa versión cuantizada e comprendemos ben que partículas son as portadoras de cada forza, na actualidade a gravidade cuántica segue ser un gran misterio e o gran enigma por desvelar dende hai x amáis dun século

Real-time vehicle speed estimation using Unmanned Aerial Vehicles for traffic surveillance

Drones are an emerging tool for traffic surveillance; however, they inherently lack the capability to solely obtain vehicle speed on the road. This Bachelor's thesis presents the design, implementation and study of a system to detect the position, velocity and type of vehicles using the video stream obtained from drones. The solution is created to be used with any kind of aerial vehicle but is tailored for the drones in the European project LABYRINTH, of which the thesis has been a part. The tool utilizes the video feed from a sole camera and the telemetry data from the drone to detect, track and project the objects present on the road from the image into reality. This allows for an estimation of their position and speed. The detection and tracking algorithm implemented is the Simple Online Real Time algorithm, which is often referred to as SORT. Once the position has been acquired, another stream is generated that displays the same video, but with the bounding boxes, velocity and confidence ratings of all identified vehicles, with an overall computing time lower than the frame rate. After implementation, the tool underwent testing in a simulated environment to determine its assets and shortcomings, and was used during the LABYRINTH traffic monitoring flight tests. The Bachelor's thesis achieves the aimed objectives with minimum resource utilization, using readily available logic and open-source software to strike an optimal balance between real-time functionality and precise detection of vehicle position.Outgoin

Dark tourism and Memorial tourism: nexus and divergences between theoretical models

In the context of the huge diversification in the field of cultural heritage, there are nowadays many touristic places whose main appeal lies in the connection with tragic events. Beyond the scope of cultural tourism, it may be confusing to classify them due to the extraordinary richness and heterogeneity of the different types of tourism as typified by tourism science. Thus, the scientific community uses several labels to name the tourism practices carried out in touristic places linked to tragedy. Among the many, it is worth pointing out dark tourism and memorial tourism, not only because of their undeniable academic impact, but also because of the media relevance gained. This article deals with the problems faced when it comes to determining the boundaries of what may be considered dark tourism or memorial tourism. After a comprehensive analysis of the theoretical contributions regarding both models, what is most relevant is why and in which contexts one term or the other is used

Estabilitat de CO en metalls hcp

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2020, Tutor: Francesc Viñes SolanaCarbon monoxide (CO) has been used as a probe molecule to study, typically, the chemical activity of Transition Metals (TMs) surfaces, but its study has been normally focused on those TMs with a face-centered cubic (fcc) crystalline structure, which are close in the Periodic Table, and so, perhaps, does not allow capturing reliable trends along the d series. Here we analyze such trends on hexagonal closed-pack (hcp) TMs by means of theoretical simulations, here relying on the accuracy of Density Functional Theory (DFT) using the Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional using suitable slab models. The detailed analysis of the obtained results allows disentangling different trends, alongside with particular surface reconstructions and CO adsorption modes no previously reported in the literature. Those TMs with low number of valence d electrons adsorb the CO stronger, specially connecting its two atoms. While the number of d electrons increase, the CO changes to be adsorbed only through the C atom, up to being no adsorbed. This trend goes along quantitatively with the d-band centre descriptor model, but qualitatively with the surface energy or the C-metal distance ones. The bonding analysis reveals a donation/back-donation mechanism, which eventually weakens the CO bond order, and so, makes its bonds longer. This has a direct effect, e.g. on the simulated infrared (IR) spectra, implying lower frequencies for the CO bond stretching vibration, which can become invisible when the CO molecule adsorbs parallel to surface due to the surface dipole selection rule. Furthermore, the results on the CO dissociation energy reveals that such a metal surface catalysed process is thermodynamically favourable for earlier TMs, but grows endothermic when going along the d serie