BRAIN COMPUTER INTERFACE - Application of an Adaptive Bi-stage Classifier based on RBF-HMM

Brain Computer Interface is an emerging technology that allows new output paths to communicate the users intentions without the use of normal output paths, such as muscles or nerves. In order to obtain their objective, BCI devices make use of classifiers which translate inputs from the users brain signals into commands for external devices. This paper describes an adaptive bi-stage classifier. The first stage is based on Radial Basis Function neural networks, which provides sequences of pre-assignations to the second stage, that it is based on three different Hidden Markov Models, each one trained with pre-assignation sequences from the cognitive activities between classifying. The segment of EEG signal is assigned to the HMMwith the highest probability of generating the pre-assignation sequence. The algorithm is tested with real samples of electroencephalografic signal, from five healthy volunteers using the cross-validation method. The results allow to conclude that it is possible to implement this algorithm in an on-line BCI device. The results also shown the huge dependency of the percentage of the correct classification from the user and the setup parameters of the classifier

Long Distance GNSS-Denied Visual Inertial Navigation for Autonomous Fixed Wing Unmanned Air Vehicles: SO(3) Manifold Filter based on Virtual Vision Sensor

This article proposes a visual inertial navigation algorithm intended to diminish the horizontal position drift experienced by autonomous fixed wing UAVs (Unmanned Air Vehicles) in the absence of GNSS (Global Navigation Satellite System) signals. In addition to accelerometers, gyroscopes, and magnetometers, the proposed navigation filter relies on the accurate incremental displacement outputs generated by a VO (Visual Odometry) system, denoted here as a Virtual Vision Sensor or VVS, which relies on images of the Earth surface taken by an onboard camera and is itself assisted by the filter inertial estimations. Although not a full replacement for a GNSS receiver since its position observations are relative instead of absolute, the proposed system enables major reductions in the GNSS-Denied attitude and position estimation errors. In order to minimize the accumulation of errors in the absence of absolute observations, the filter is implemented in the manifold of rigid body rotations or SO (3). Stochastic high fidelity simulations of two representative scenarios involving the loss of GNSS signals are employed to evaluate the results. The authors release the C++ implementation of both the visual inertial navigation filter and the high fidelity simulation as open-source software.Comment: 27 pages, 14 figures. arXiv admin note: substantial text overlap with arXiv:2205.1324

Exploiting Post-mitotic Yeast Cultures to Model Neurodegeneration

Over the last few decades, the budding yeast Saccharomyces cerevisiae has been extensively used as a valuable organism to explore mechanisms of aging and human age-associated neurodegenerative disorders. Yeast models can be used to study loss of function of disease-related conserved genes and to investigate gain of function activities, frequently proteotoxicity, exerted by non-conserved human mutant proteins responsible for neurodegeneration. Most published models of proteotoxicity have used rapidly dividing cells and suffer from a high level of protein expression resulting in acute growth arrest or cell death. This contrasts with the slow development of neurodegenerative proteotoxicity during aging and the characteristic post-mitotic state of the affected cell type, the neuron. Here, we will review the efforts to create and characterize yeast models of neurodegeneration using the chronological life span model of aging, and the specific information they can provide regarding the chronology of physiological events leading to neurotoxic proteotoxicity-induced cell death and the identification of new pathways involved

A waypoint-based mission planner for a farmland coverage with an aerial robot - a precision farming tool

Remote sensing (RS) with aerial robots is becoming more usual in every day time in Precision Agriculture (PA) practices, do to their advantages over conventional methods. Usually, available commercial platforms providing off-the-shelf waypoint navigation are adopted to perform visual surveys over crop fields, with the purpose to acquire specific image samples. The way in which a waypoint list is computed and dispatched to the aerial robot when mapping non empty agricultural workspaces has not been yet discussed. In this paper we propose an offline mission planner approach that computes an efficient coverage path subject to some constraints by decomposing the environment approximately into cells. Therefore, the aim of this work is contributing with a feasible waypoints-based tool to support PA practice

Seguimiento de óptimos en movimiento a través de predicciones basadas en filtros de Kalman

Los problemas de optimización dinámica tratan con entornos variables. En este artículo se presentan varias técnicas para integrar información de movimiento en un algoritmo genético, cuando la función de fitness cambia con el tiempo y los cambios en el óptimo siguen una ley no basada en el azar. Se propone un mecanismo para estimar dicha ley con elfin de mejorar la capacidad de seguimiento del optimo, que finalmente se prueba con una aplicación de seguimiento de objetos en movimiento para un sistema de visión artificial

Trainer of professional training: Teachers ´perceptions of their teaching

El presente artículo da cuenta de un estudio cuyo objetivo fue explorar y analizar desde una perspectiva Europea, las percepciones que tienen los profesionales de la formación profesional, en particular de la Educación Superior Técnico Profesional chilena que están vinculados con la industria y que realizan clases como parte de su jornada laboral. Se describieron el cómo sus aspectos personales, formación académica, experiencia profesional y los recursos de su entorno afectan en la identificación en su rol docente y qué importancia les otorgan a sus funciones de planificación, desarrollo y evaluación de la formación. El estudio fue descriptivo con un muestreo no probabilístico intencional e institucional y se empleó la combinación de metodologías cuantitativas y cualitativas. La población invitada estuvo conformada por profesionales con dedicación parcial a la docencia de una institución de educación superior. Los resultados evidencian que estos profesionales definen su tarea, de manera que entienden sus relaciones con otros que hacen lo mismo, o bien de modelos que traen de sus preconcepciones docentes. Se destaca que su alto grado de especialización técnica, la que se traduce en formación, es un gran elemento de motivación para desarrollar la actividad docente. Se discute que ser un buen profesor con dedicación parcial e identificarse con ello, tiene algo de logro personal, pero también es una consecuencia del modo de operar, gracias al apoyo de un grupo de trabajo, un departamento, valores y procedimientos docentes

Miniature Quad-rotor Dynamics Modeling & Guidance for Vision-based Target Tracking Control Tasks

This paper presents the dynamics modeling and the control & guidance architecture for specific target tracking indoors tasks using a miniature quad-rotor. Our objective is to develop a testbed using Matlab for experimentation and simulation of dynamics, control and guidance methods within a strong interplay between the hardware on board and software provisioned

Formador de la educación superior técnico profesional : percepciones sobre su trabajo docente

El estudio exploró y analizó las percepciones que tienen los profesionales de la Educación Superior Técnico Profesional chilena que trabajan en la industria y realizan docencia como parte de su jornada laboral. Se describió cómo sus aspectos personales, formación académica, experiencia profesional y los recursos del entorno afectan en su rol docente, y qué importancia conceden a sus funciones de planificación, desarrollo y evaluación de la formación. Se evidenció que su labor se basa en modelos que traen de sus preconcepciones docentes o de la relación con sus pares. Su alto grado de especialización técnica, traducida en formación, es un elemento de motivación para realizar docencia. Se discute que ser un buen profesor con dedicación parcial e identificarse con ello tiene algo de logro personal, pero también es una consecuencia del modo de operar, gracias al apoyo de un grupo de trabajo, un departamento, procedimientos, valores y formación permanenteThis study explored and analyzed the perceptions of technical training professionals. We centered on teachers of technical professional higher education in Chile who work for the industry and who teach in a part-time schedule. We described how their personal history, education, training, professional experience and resources affect their professional performance as teachers, as well as, the functions of planning, development and assessment of their teaching. The results showed that their tasks reflect models created from relationships with peers or from models that they bring from their preconceptions. A high level of technical expertise, which results in the training, is an element of motivation when teaching. We discuss the idea that while a good part-time teacher is somewhat of a personal achievement; it is also a result of operating model thanks provided by working groups, values, teaching methods, and constant learningO estudo explorou e analisou as percepções que possuem os profissionais da Educação Superior Técnica Profissional chilena que trabalham em indústrias e que dão aulas como parte da sua jornada laboral. Estes descreveram como suas características pessoais, formação acadêmica, experiência profissional e os recursos do ambiente interferem no seu trabalho docente e que importância eles dão a suas funções de planejamento, desenvolvimento e avaliação da formação. Evidenciou-se que o seu trabalho é baseado em modelos que trazem das suas preconcepções docentes ou da relação com os seus pares. Seu alto grau de especialização técnica, traduzida em formação, é um elemento de motivação para realizar a docência. Discute-se que ser um bom professor com dedicação parcial e identificar-se com isto, contém algo de realização pessoal, mas também é consequência do modo de trabalhar, graças ao apoio de um grupo de trabalho, um departamento, procedimentos, valores e formação permanent

Advanced UAV Trajectory Generation: Planning and Guidance

As technology and legislation move forward (JAA & Eurocontrol, 2004) remotely controlled, semi-autonomous or autonomous Unmanned Aerial Systems (UAS) will play a significant role in providing services and enhancing safety and security of the military and civilian community at large (e.g. surveillance and monitoring) (Coifman et al., 2004). The potential market for UAVs is, however, much bigger than just surveillance. UAVs are ideal for risk assessment and neutralization in dangerous areas such as war zones and regions stricken by disaster, including volcanic eruptions, wildfires, floods, and even terrorist acts. As they become more autonomous, UAVs will take on additional roles, such as air-to-air combat and even planetary science exploration (Held et al., 2005). As the operational capabilities of UAVs are developed there is a perceived need for a significant increase in their level of autonomy, performance, reliability and integration with a controlled airspace full of manned vehicles (military and civilian). As a consequence researchers working with advanced UAVs have moved their focus from system modeling and low-level control to mission planning, supervision and collision avoidance, going from vehicle constraints to mission constraints (Barrientos et al., 2006). This mission-based approach is most useful for commercial applications where the vehicle must accomplish tasks with a high level of performance and maneuverability. These tasks require flexible and powerful trajectory-generation and guidance capabilities, features lacking in many of the current commercial UAS. For this reason, the purpose of this work is to extend the capabilities of commercially available autopilots for UAVs. Civil systems typically use basic trajectory-generation algorithms, capable only of linear waypoint navigation (Rysdyk, 2003), with a minimum or non-existent control over the trajectory. These systems are highly constrained when maneuverability is a mission requirement. On the other hand, military researchers have developed algorithms for high-performance 3D path planning and obstacle avoidance (Price, 2006), but these are highly proprietary technologies that operate with different mission constraints (target acquisition, threat avoidance and situational awareness) so they cannot be used in civil scenarios