Neural Network Based Reinforcement Learning for Audio-Visual Gaze Control in Human-Robot Interaction

This paper introduces a novel neural network-based reinforcement learning approach for robot gaze control. Our approach enables a robot to learn and to adapt its gaze control strategy for human-robot interaction neither with the use of external sensors nor with human supervision. The robot learns to focus its attention onto groups of people from its own audio-visual experiences, independently of the number of people, of their positions and of their physical appearances. In particular, we use a recurrent neural network architecture in combination with Q-learning to find an optimal action-selection policy; we pre-train the network using a simulated environment that mimics realistic scenarios that involve speaking/silent participants, thus avoiding the need of tedious sessions of a robot interacting with people. Our experimental evaluation suggests that the proposed method is robust against parameter estimation, i.e. the parameter values yielded by the method do not have a decisive impact on the performance. The best results are obtained when both audio and visual information is jointly used. Experiments with the Nao robot indicate that our framework is a step forward towards the autonomous learning of socially acceptable gaze behavior.Comment: Paper submitted to Pattern Recognition Letter

Effect of wounding on pepper fruit resistance to “Botrytis cinérea”

[Resumen] Los frutos son productos perecederos que se encuentran expuestos de forma continua a factores que disminuyen su valor, tanto económico como nutricional, por lo que numerosos estudios se centran en cómo frenar o evitar su deterioro. En este estudio se intentó inducir resistencia frente a Botrytis cinerea en frutos de pimiento verde, Capsicum annuum, mediante la aplicación de heridas y heridas combinadas con etileno sobre la superficie del fruto. Se demostró que tanto las heridas, como la combinación de heridas y etileno no inducen resistencia a Botrytis cinerea en el fruto. Por el contrario las heridas aumentan la susceptibilidad del fruto, ya que al romper la cutícula eliminan la principal barrera defensiva del fruto frente a las infecciones por parte de organismos patógenos. Los análisis bioquímicos realizados sobre pimientos control y heridos mostraron que el contenido de compuestos fenólicos solubles totales permanecía inalterado mientras que el contenido de sólidos solubles totales registraba un aumento significativo en respuesta a las heridas. Además se realizó un muestreo en seis establecimientos comerciales con el fin de determinar si existen heridas u otros daños en los frutos a la venta, demostrándose que si existen diferencias en cuanto a la calidad de los frutos en función del establecimiento elegido.[Resumo] Os froitos son produtos perecedoiros que se atopan expostos de forma continua a factores que diminúen o seu valor, tanto económico como nutricional, polo que numerosos estudios céntranse en como frear ou evitar o seu deterioro. Neste estudio intentouse inducir resistencia frente a Botrytis cinerea en froitos de pemento verde, Capsicum annuum, mediante a aplicación de feridas e feridas combinadas con etileno sobre a superficie do froito. Demostrouse que tanto as feridas, coma a combinación de feridas e etileno non inducen resistencia a Botrytis cinerea nos froitos. Polo contrario, as feridas aumentan a susceptibilidade do froito, xa que ó romper a cutícula eliminan a principal barreira defensiva do froito frente ás infeccións por parte dos organismos patóxenos. As análises bioquímicas realizadas sobre pementos control e feridos amosaron que o contido de compostos fenólicos solubles totais non cambiou, mais o contido en sólidos solubles totais rexistrou un aumento significativo en resposta as feridas. Ademais realizouse unha mostraxe en seis establecementos comerciais coa fin de determinar se existen feridas ou outros danos nos froitos á venda, demostrándose que si existen diferencias en canto á calidade dos froitos en función do establecemento escollido.[Abstract] Fruits are perishable products that are constantly exposed to factors that decrease not only their economical value but their nutritional value too. That is why a high number of researches are based on the way we could stop or avoid their deterioration. In this research, we have tried to induce resistance to Botrytis cinerea in green pepper fruits, Capsicum anuum, by making wounds over the surface of the fruit and treating them with ethylene plus wounds. It has been determined that both, wounds and ethylene plus wounds do not induce resistance to Botrytis cinerea in the fruits. Indeed, wounds caused an increase in susceptibility, because they break the cuticle, the main fruit’s defensive barrier against infections caused by pathogen organisms. Biochemical analysis we have carried out in control and wounded peppers revealed that the content of total soluble phenolic compounds remain unchanged, while the content of total soluble solids increased as a response to wounding. In addition, a comparative study was carried out, surveying six different supermarkets in order to determine if commercial fruits were wounded or damaged in other ways. We found differences in fruit quality among different supermarkets.Traballo fin de grao (UDC.CIE). Bioloxía. Curso 2014/201

Investigation of the effective response of 2-1-2 piezoelectric composites

International audienceThe question of the effective response of two-phase hybrid "fibrous-laminate" piezoelectric composites, with periodic microstructure, is adressed with two homogenization approaches: a full-field numerical scheme based on Fourier transform and a simplifying approach relying on a decoupled two-step homogenisation process. In the case of a two-phase epoxy/PZT composite, this latter is shown to overestimate out-of-plane effective piezoelectric coefficients

A Review of Symbolic, Subsymbolic and Hybrid Methods for Sequential Decision Making

The field of Sequential Decision Making (SDM) provides tools for solving Sequential Decision Processes (SDPs), where an agent must make a series of decisions in order to complete a task or achieve a goal. Historically, two competing SDM paradigms have view for supremacy. Automated Planning (AP) proposes to solve SDPs by performing a reasoning process over a model of the world, often represented symbolically. Conversely, Reinforcement Learning (RL) proposes to learn the solution of the SDP from data, without a world model, and represent the learned knowledge subsymbolically. In the spirit of reconciliation, we provide a review of symbolic, subsymbolic and hybrid methods for SDM. We cover both methods for solving SDPs (e.g., AP, RL and techniques that learn to plan) and for learning aspects of their structure (e.g., world models, state invariants and landmarks). To the best of our knowledge, no other review in the field provides the same scope. As an additional contribution, we discuss what properties an ideal method for SDM should exhibit and argue that neurosymbolic AI is the current approach which most closely resembles this ideal method. Finally, we outline several proposals to advance the field of SDM via the integration of symbolic and subsymbolic AI

NeSIG: A Neuro-Symbolic Method for Learning to Generate Planning Problems

In the field of Automated Planning there is often the need for a set of planning problems from a particular domain, e.g., to be used as training data for Machine Learning or as benchmarks in planning competitions. In most cases, these problems are created either by hand or by a domain-specific generator, putting a burden on the human designers. In this paper we propose NeSIG, to the best of our knowledge the first domain-independent method for automatically generating planning problems that are valid, diverse and difficult to solve. We formulate problem generation as a Markov Decision Process and train two generative policies with Deep Reinforcement Learning to generate problems with the desired properties. We conduct experiments on several classical domains, comparing our method with handcrafted domain-specific generators that generate valid and diverse problems but do not optimize difficulty. The results show NeSIG is able to automatically generate valid problems of greater difficulty than the competitor approaches, while maintaining good diversity

Avenida [16]: Reforma edificio Avenida Doctor Tourón, 16, Vilagarcía de Arousa (Pontevedra)

[Resumen]: El presente Proyecto fin de grado se realiza la rehabilitación de un edificio situado en la Avenida Doctor Tourón 16, en Vilagarcía de Arousa con el fin de reacondicionar el bajo para la creación de un estudio de arquitectura y una zona para un espacio multifuncional donde se puedan realizar eventos, así como una zona para exposiciones, así como la rehabilitación de las plantas superiores con el fin de crear dos viviendas. El objetivo de este proyecto es evitar modificar lo mínimo posible la arquitectura de este edificio, conservando todo lo que sea posible, con el fin de demostrar que no es necesario acabar con la arquitectura de esta época para lograr viviendas confortables y modernas. La planta baja está compuesta por varias zonas que están conectadas con un jardín trasero, lo que permite el contacto con la naturaleza en un entorno urbano. Las plantas superiores están divididas en una zona de día que da a la calle principal, y una zona de noche que da al patio trasero. Se justifica el presente proyecto con el fin de validar su correcta ejecución en cumplimiento de la legislación vigente. El trabajo se compone de cinco tomos: TOMO I: Memoria, en la que se incluye la memoria descriptiva, memoria urbanística y la memoria constructiva. Se justifica el cumplimiento del CTE, así como otros reglamentos. Finalmente se incluye en los anejos todos los cálculos y especificaciones necesarias de las instalaciones, iluminación, estudio de gestión de residuos de construcción y demolición, plan de control de calidad y el estudio de seguridad y salud -- TOMO II: Compuesto por toda la documentación gráfica -- TOMO III: Donde se incluye el Pliego de Condiciones -- TOMO IV: Donde se incluyen las Mediciones necesarias -- TOMO V: Donde se incluye el Presupuesto del Proyecto.[Abstract]: This Final Degree Project involves the rehabilitation of a building located at Avenida Doctor Tourón 16, in Vilagarcía de Arousa in order to recondition the ground floor for the creation of an architecture studio and an area for a multifunctional space where they can events, as well as an area for exhibitions, as well as the rehabilitation of the upper floors in order to create two houses. The objective of this project is to avoid modifying the architecture of this building as little as possible, preserving as much as possible, in order to demonstrate that it is not necessary to end the architecture of this era to achieve comfortable and modern homes. The ground floor is made up of several areas that are connected to a rear garden, allowing contact with nature in an urban environment. The upper floors are divided into a day area that faces the main street, and a night area that overlooks the backyard. This project is justified in order to validate its correct execution in compliance with current legislation. The work consists of five volumes: VOLUME I: Memory, which includes the descriptive memory, urban memory and constructive memory. Compliance with the CTE is justified, as well as other regulations. Finally, all the necessary calculations and specifications of the facilities, lighting, construction and demolition waste management study, quality control plan and the health and safety study are included in the annexes -- VOLUME II: Comprised of all graphic documentation -- VOLUME III: Where the Conditions Specifications are included -- VOLUME IV: Where the necessary Measurements are included -- VOLUME V: Where the Project Budget is included.Traballo fin de grao (UDC.EUAT). Arquitectura técnica. Curso 2022/202

Custom Structure Preservation in Face Aging

In this work, we propose a novel architecture for face age editing that can produce structural modifications while maintaining relevant details present in the original image. We disentangle the style and content of the input image and propose a new decoder network that adopts a style-based strategy to combine the style and content representations of the input image while conditioning the output on the target age. We go beyond existing aging methods allowing users to adjust the degree of structure preservation in the input image during inference. To this purpose, we introduce a masking mechanism, the CUstom Structure Preservation module, that distinguishes relevant regions in the input image from those that should be discarded. CUSP requires no additional supervision. Finally, our quantitative and qualitative analysis which include a user study, show that our method outperforms prior art and demonstrates the effectiveness of our strategy regarding image editing and adjustable structure preservation. Code and pretrained models are available at https://github.com/guillermogotre/CUSP.Comment: 36 pages, 21 figure

Automatic evolutionary medical image segmentation using deformable models

International audienceThis paper describes a hybrid level set approach to medical image segmentation. The method combines region-and edge-based information with the prior shape knowledge introduced using deformable registration. A parameter tuning mechanism, based on Genetic Algorithms, provides the ability to automatically adapt the level set to different segmentation tasks. Provided with a set of examples, the GA learns the correct weights for each image feature used in the segmentation. The algorithm has been tested over four different medical datasets across three image modalities. Our approach has shown significantly more accurate results in comparison with six state-of-the-art segmentation methods. The contributions of both the image registration and the parameter learning steps to the overall performance of the method have also been analyzed