3D Segmentation Method for Natural Environments based on a Geometric-Featured Voxel Map

This work proposes a new segmentation algorithm for three-dimensional dense point clouds and has been specially designed for natural environments where the ground is unstructured and may include big slopes, non-flat areas and isolated areas. This technique is based on a Geometric-Featured Voxel map (GFV) where the scene is discretized in constant size cubes or voxels which are classified in flat surface, linear or tubular structures and scattered or undefined shapes, usually corresponding to vegetation. Since this is not a point-based technique the computational cost is significantly reduced, hence it may be compatible with Real-Time applications. The ground is extracted in order to obtain more accurate results in the posterior segmentation process. The scene is split into objects and a second segmentation in regions inside each object is performed based on the voxel’s geometric class. The work here evaluates the proposed algorithm in various versions and several voxel sizes and compares the results with other methods from the literature. For the segmentation evaluation the algorithms are tested on several differently challenging hand-labeled data sets using two metrics, one of which is novel.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Supervector extraction for encoding speaker and phrase information with neural networks for text-dependent speaker verification

In this paper, we propose a new differentiable neural network with an alignment mechanism for text-dependent speaker verification. Unlike previous works, we do not extract the embedding of an utterance from the global average pooling of the temporal dimension. Our system replaces this reduction mechanism by a phonetic phrase alignment model to keep the temporal structure of each phrase since the phonetic information is relevant in the verification task. Moreover, we can apply a convolutional neural network as front-end, and, thanks to the alignment process being differentiable, we can train the network to produce a supervector for each utterance that will be discriminative to the speaker and the phrase simultaneously. This choice has the advantage that the supervector encodes the phrase and speaker information providing good performance in text-dependent speaker verification tasks. The verification process is performed using a basic similarity metric. The new model using alignment to produce supervectors was evaluated on the RSR2015-Part I database, providing competitive results compared to similar size networks that make use of the global average pooling to extract embeddings. Furthermore, we also evaluated this proposal on the RSR2015-Part II. To our knowledge, this system achieves the best published results obtained on this second part

Class token and knowledge distillation for multi-head self-attention speaker verification systems

This paper explores three novel approaches to improve the performance of speaker verification (SV) systems based on deep neural networks (DNN) using Multi-head Self-Attention (MSA) mechanisms and memory layers. Firstly, we propose the use of a learnable vector called Class token to replace the average global pooling mechanism to extract the embeddings. Unlike global average pooling, our proposal takes into account the temporal structure of the input what is relevant for the text-dependent SV task. The class token is concatenated to the input before the first MSA layer, and its state at the output is used to predict the classes. To gain additional robustness, we introduce two approaches. First, we have developed a new sampling estimation of the class token. In this approach, the class token is obtained by sampling from a list of several trainable vectors. This strategy introduces uncertainty that helps to generalize better compared to a single initialization as it is shown in the experiments. Second, we have added a distilled representation token for training a teacher-student pair of networks using the Knowledge Distillation (KD) philosophy, which is combined with the class token. This distillation token is trained to mimic the predictions from the teacher network, while the class token replicates the true label. All the strategies have been tested on the RSR2015-Part II and DeepMine-Part 1 databases for text-dependent SV, providing competitive results compared to the same architecture using the average pooling mechanism to extract average embeddings

Sialolithiasis. Proposal for a new minimally invasive procedure: piezoelectric surgery

Sialolithiasis is the presence of stones in the ducts of the salivary glands. Most episodes are unique, and 60-80% are located exclusively in the main excretory duct. The main clinical manifestations are swelling and pain typically before, during or after meals that decreases if the obstruction is not complete. The highest prevalence of lithiasis is in the submandibular gland -87%-, whose secretion is more viscous, followed by the parotid gland -10%- and finally the sublingual gland -3%-. The most significant consequences are caused by the prolonged blockage of the duct by a stone, which can produce a persistent ductal dilatation with a swelling that does not subside, and could lead to the complete degeneration of the parenchyma, becoming a hot spot where secondary infections may occur, leading to acute bacterial sialadenitis or glandular abscesses. Treatment options range from a single probing extraction, extraction with sialographic control using the sialoen - doscope, LASER intraductal lithotripsy, lithotripsy extracorporeal shock wave (ESWL), to the surgical techniques combining open duct with endoscopic or glandular removal. We propose, with regard to a case, the use of a simple piezoelectric device which, tunnelling through the glandular channel by the ostium, allows stone fragmentation, wi - thout damaging the surrounding soft tissue. Stone removal by this less invasive method reduces the need for more complex and expensive techniques. The postoperative course without retraction of the ostium, and the regaining of functionality is favourable

El nacimiento del “Emplazamiento de Producto” en el contexto de la I Guerra Mundial: Hollywood y el período 1913-1920 como marcos de referencia

Both the First and the Second World War meant the beginning of most of the technologies, concepts and formats that have to do with contemporary communication, especially with regard to propaganda and commercial communication. This research proposes the period of World War I as the most significant framework in establishing the model and concept of the technique named “product placement”, as applied to film production and circumscribed, especially, to Hollywood movies. To do this, we determine a concept based on the different authors who have addressed the issue, we present various historical currents regarding its origin, and –finally- try to decide in what period begins to realize most of the defining features of the technique.Las guerras mundiales han representado el comienzo de la mayor parte de las tecnologías, conceptos y formatos que tienen que ver con la comunicación actual, especialmente en lo relativo a la propaganda y la comunicación comercial. Esta investigación propone el periodo de la I Guerra Mundial como el marco de referencia más significativo en la constitución del modelo y concepto de la técnica denominada “emplazamiento de producto”, aplicada a la producción cinematográfica y circunscrita, muy especialmente, a las películas de Hollywood. Para ello, determinamos un concepto basado en los distintos autores que han tratado el tema, exponemos las distintas corrientes históricas relativas a su origen, y –finalmente- tratamos de dilucidar qué período sería aquel en el que comienzan a darse la mayor parte de los rasgos definitorios de la técnica

EL OLVIDO DE LOS SILENCIOS NEGROS EN EL VALLE DEL RISARALDA: ENTRE LA HISTORIA DE LOS VENCEDORES Y LA MEMORIA DE LOS SUBALTERNOS.

El asentamiento de Cañaveral del Carmen, al sur del hoy Municipio de La Virginia (Risaralda), desapareció por efecto de los procesos de acumulación y concentración de tierras hacia 1923 por parte de empresarios territoriales, luego de un prolongado forcejeo jurídico que favoreció las pretensiones de los hacendados quienes emplearon todos los recursos, incluido la violencia para lograr sus objetivos usurpadores. De esta manera el valle del río Risaralda, al occidente del Viejo Caldas, pasó de ser un lugar inhóspito, agreste y refugio de economía de la campesina a lo largo del siglo XIX, a constituirse en un emporio ganadero y cañero, dando al traste con los vestigios bioculturales de la frontera cimarrona que se había arraigado allí desde finales del siglo XVIII

The Spanish legal-administrative regime of the so-called tourist flats

RESUMEN: En el presente trabajo analizaremos detalladamente el régimen jurídicoadministrativo español de los denominados pisos turísticos. En concreto, se abordan los pisos turísticos bajo las modalidades de apartamentos turísticos y viviendas de uso turístico. ABSTRACT: In the present paper we will analyze in detail the Spanish legal administrative regime of the so-called tourist flats. Specifically, tourist flats are addressed under the modalities of tourist apartments and housing of tourist use

El olvido de los silencios negros en el valle del Risaralda 1880-1973

Los procesos de poblamiento y colonización en la cuenca media del valle geográfico del río Cauca, desde el siglo XVIII hasta finales del siglo XIX, dan cuenta de varios fenómenos de los que se debe ocupar la historiografía para desarrollar hipótesis asociadas a tipologías de frontera, como la cimarrona, que de algunas manera se pueden interpretar como rasgos de la configuración de hegemonías comunales y, por tanto, interpelar los enfoques que le otorgan a la colonización antioqueña un carácter totalizante. Los olvidos y silencios sobre el trasfondo cultural, social, económico y simbólico de la frontera cimarrona de la cual hicieron parte Sopinga y mucho más tarde Cañaveral del Carmen, en la confluencia de los ríos Cauca y Risaralda, son en sí mismo el problema central de nuestra investigación y reflexión historiográfica con el objetivo de establecer los efectos que produjo la colonización empresarial que dio origen a una frontera agroexportadora con pretensiones de civilizar y modernizar el territorio. El modelo explicativo adoptado para abordar el estudio de este fenómeno se basó en analizar los tipos de colonización y frontera en el valle del Risaralda, y en particular acoger la tesis de frontera-refugio, desde la cual es posible no solo contrastar el concepto de frontera agrícola, sino interpretar la configuración de una frontera cimarrona a través de la constitución de Palenques a lo largo de los ríos Magdalena y Cauca, como se observa en este trabajo. La historia oficial del valle del Risaralda está contenida en novelas y relatos, como resultado de los productos culturales de la frontera empresarial. De ahí que su análisis a la luz del uso de fuentes primarias y conceptos teóricos acogidos, permitieron apropiar una reflexión asociada al problema de los olvidos, silencios, negaciones y ocultamientos propios de unas narrativas que, de manera u otra, se congraciaron con las voces de los vencedores.The processes of settlement and colonization in the middle basin of geographic Cauca valley, from the eighteenth century to the late nineteenth century, account for several phenomena that must be dealt historiography to develop hypotheses associated with types of border, as the Cimarron typology that some way can be interpreted as features of hegemonies communal settings and therefore challenged approaches that give a totalizing colonization of Antioquia character. The forgetfulness and silence on the cultural, social, economic and symbolic background of Cimarron border which were part Sopinga and much later Canaveral del Carmen, at the confluence of the rivers Cauca and Risaralda, are themselves the central problem of our historical research and reflection in order to establish the effects that corporate colonization occurred that gave rise to an agricultural export border claims of civilizing and modernizing the territory. The explanatory model adopted for the study of this phenomenon was based on analyzing the types of colonization and border in the valley of Risaralda, and particularly welcome the thesis-border refuge, from which it is possible not only to test the concept of border setting, but to interpret the configuration of a Cimarron border through the establishment of Palenques along the Magdalena and Cauca rivers, as observed in this work. The official history of the valley of Risaralda is contained in novels and stories as a result of the cultural products of the business frontier. Hence its analysis in light of the use of primary sources and theoretical concepts welcomed, allowed to appropriate reflection problem associated with forgetfulness, silence, denial and concealment of a narrative own that, somehow or other, to ingratiate himself with the voices of the victors