Data stream analysis in sliding windows: random sampling and other problems

In many data stream applications we need to perform some analysis in a "window" or subsequence of contiguous elements, quite often the last M elements seen or the elements seen in the last X time units. For example, we might be interested in obtaining a random sample of the distinct elements seen in the last 10 minutes, or estimate how many distinct elements have been processed among the last 100000 processed items. Given the restrictions in processing time and memory available, exact solutions become unfeasible and we seek for randomized algorithms which are fast, have low memory requirements and provide probabilistic guarantees. In this project we will implement some of the algorithms available in the literature and conduct extensive experiments to assess their performance and compare their relative merits; we will also develop novel and original algorithms or variants of existing algorithm to compare them with the state-of-the-art solutions. We will mostly focus in algorithms to obtain random samples, a fundamental task for more complex statistical inference: detecting outliers, finding frequent items, detecting unusual patterns, etc

Precise localization for aerial inspection using augmented reality markers

The final publication is available at link.springer.comThis chapter is devoted to explaining a method for precise localization using augmented reality markers. This method can achieve precision of less of 5 mm in position at a distance of 0.7 m, using a visual mark of 17 mm × 17 mm, and it can be used by controller when the aerial robot is doing a manipulation task. The localization method is based on optimizing the alignment of deformable contours from textureless images working from the raw vertexes of the observed contour. The algorithm optimizes the alignment of the XOR area computed by means of computer graphics clipping techniques. The method can run at 25 frames per second.Peer ReviewedPostprint (author's final draft

Face perception: An integrative review of the role of spatial frequencies

The aim of this article is to reinterpret the results obtained from the research analyzing the role played by spatial frequencies in face perception. Two main working lines have been explored in this body of research: the critical bandwidth of spatial frequencies that allows face recognition to take place (the masking approach), and the role played by different spatial frequencies while the visual percept is being developed (the microgenetic approach). However, results obtained to date are not satisfactory in that no single explanation accounts for all the data obtained from each of the approaches. We propose that the main factor for understanding the role of spatial frequencies in face perception depends on the interaction between the demands of the task and the information in the image (the diagnostic recognition approach). Using this new framework, we review the most significant research carried out since the early 1970s to provide a reinterpretation of the data obtained

Forecasting a Language Shift Based on Cellular Automata

Language extinction as a consequence of language shifts is a widespread social phenomenon that affects several million people all over the world today. An important task for social sciences research should therefore be to gain an understanding of language shifts, especially as a way of forecasting the extinction or survival of threatened languages, i.e., determining whether or not the subordinate language will survive in communities with a dominant and a subordinate language. In general, modeling is usually a very difficult task in the social sciences, particularly when it comes to forecasting the values of variables. However, the cellular automata theory can help us overcome this traditional difficulty. The purpose of this article is to investigate language shifts in the speech behavior of individuals using the methodology of the cellular automata theory. The findings on the dynamics of social impacts in the field of social psychology and the empirical data from language surveys on the use of Catalan in Valencia allowed us to define a cellular automaton and carry out a set of simulations using that automaton. The simulation results highlighted the key factors in the progression or reversal of a language shift and the use of these factors allowed us to forecast the future of a threatened language in a bilingual community.Cellular Automata, Computational Simulations, Language, Social Dynamics

La cova novella de na llebrona (Manacor, Mallorca)

[cat] En el present treball es descriu la cova Novella de na Llebrona, una cavitat descoberta en el terme municipal de Manacor durant les tasques de construcció de la nova carretera que voreja Portocristo cap al sud. Es tracta d’una cova de dimensions discretes, ja que tan sols assoleix devers 250 m de desenvolupament. No obstant això, en el seu interior es varen localitzar restes de ceràmica posttalaiòtica i també de fauna prehumana del Quaternari de les Balears (Myotragus balearicus i Hypnomys morpheus). Les tasques espeleològiques efectuades han permès la preservació de la cavitat, sense que es vegi afectada per les obres de la nova carretera.[eng] This paper describes the Cova Novella de Na Llebrona, a cave discovered in the municipality of Manacor during construction works of a new road along the south of Portocristo village. It is a cave of discrete dimensions, since only reaches 250 meters of development. Nevertheless, remains of Posttalaiotic pottery and pre-human fauna from the Quaternary of the Balearic Islands (Myotragus balearicus and Hypnomys morpheus) were found inside the cave. The performed speleological tasks have allowed the preservation of the cave, without being affected by the construction of the new road

Neural Cellular Automata Manifold

Very recently, the Neural Cellular Automata (NCA) has been proposed to simulate the morphogenesis process with deep networks. NCA learns to grow an image starting from a fixed single pixel. In this work, we show that the neural network (NN) architecture of the NCA can be encapsulated in a larger NN. This allows us to propose a new model that encodes a manifold of NCA, each of them capable of generating a distinct image. Therefore, we are effectively learning an embedding space of CA, which shows generalization capabilities. We accomplish this by introducing dynamic convolutions inside an Auto-Encoder architecture, for the first time used to join two different sources of information, the encoding and cells environment information. In biological terms, our approach would play the role of the transcription factors, modulating the mapping of genes into specific proteins that drive cellular differentiation, which occurs right before the morphogenesis. We thoroughly evaluate our approach in a dataset of synthetic emojis and also in real images of CIFAR10. Our model introduces a general-purpose network, which can be used in a broad range of problems beyond image generation

Un rey, un mar y dos ciudades. Las entradas de Alfonso el Magnánimo en Valencia (1424) y Nápoles (1443). Transferencias e influencias de ida y vuelta.

On February 26th 1443 Alfonso V of Aragon made his triumphal entrance to Naples, a fact that was carved in the relief that crowns the entrance to Castelnuovo. This frieze consciously forgets some of the most important characteristics of the Neapolitan event, which is closely related to the image that the monarch himself wished to spread. In this paper we will analyse the aforementioned entry comparing it with its Iberian precedents, especially those that took place in Valencia. With this aim we will focus on the representations and modifications in the urban visual and soundscapes, which will allow us to discover influences and mutual exchanges, thus trying to overcome the dichotomy between the Middle Ages and modernity, and providing a more inclusive vision to a time of change.El 26 de febrero de 1443 Alfonso V de Aragón realizaba su entrada triunfal en Nápoles, hecho que quedaría plasmado en el relieve que corona la entrada al Castelnuovo. Dicho friso olvida conscientemente algunas de las características más importantes del evento napolitano, hecho íntimamente relacionado con la imagen que el propio monarca deseaba difundir. En este artículo analizaremos la mencionada entrada comparándola con sus precedentes ibéricos, en especial los realizados en Valencia. Para ello, nos centraremos en las representaciones y modificaciones en el paisaje visual y sonoro urbano, lo que nos permitirá descubrir influencias e intercambios mutuos, intentando superar así la dicotomía entre edad media y modernidad y aportando una visión más integradora a una época de cambios.  &nbsp