Student Reciprocal Peer Teaching as a Method for Active Learning: An Experience in an Electrotechnical Laboratory

Active learning is one of the most efficient mechanisms for learning, according to the psychology of learning. When students act as teachers for other students, the communication is more fluent and knowledge is transferred easier than in a traditional classroom. This teaching method is referred to in the literature as reciprocal peer teaching. In this study, the method is applied to laboratory sessions of a higher education institution course, and the students who act as teachers are referred to as ‘‘laboratory monitors.’’ A particular way to select the monitors and its impact in the final marks is proposed. A total of 181 students participated in the experiment, experiences with laboratory monitors are discussed, and methods for motivating and training laboratory monitors and regular students are proposed. The types of laboratory sessions that can be led by classmates are discussed. This work is related to the changes in teaching methods in the Spanish higher education system, prompted by the Bologna Process for the construction of the European Higher Education Area

Distributes award protocol: A cooperation and communication method for robots.

In this Master’s Thesis a new Distributed Award Protocol (DAP) for robot communication and cooperation is presented. Task assignment (contract awarding) is done dynamically with contracts assigned to robots based upon the best bid received. Instead of having a manager and a contractor it is proposed a fully distributed bidding/awarding mechanism without a distinguished master. The best bidding robots are awarded with contract for execution. The contractors make decisions locally. This brings the following benefits: no communication bottleneck, low computational power requirement, increased robustness. DAP can handle multitasking. Tasks can be injected into system during the execution of already allocated tasks. As tasks have priorities, in the next cycle after taking into account actual bid parameters of all robots, tasks can be re-allocated. The aim is to minimize a global cost function which is a compromise between cost of task execution and cost of resources usage. Information about tasks and bid values is spread among robots with the use of a Round Robin Route, which is a novel solution proposed in this work. This method allows also identifying failed robots. Such failed robot is eliminated from the list of awarded robots and its replacement is found so the task is still executed by a team. If the failure of a robot was temporary (e.g. communication noise) and the robot can recover, it can again participate in the next bidding/awarding process. Using a bidding/awarding mechanism allows robots to dynamically relocate among tasks. This is also contributes to system robustness. DAP was evaluated through multiple experiments done in the multi-robot simulation system. Various scenarios were tested to check the idea of the main algorithm. Different failures of robots (communication failures, partial hardware malfunctions) were simulated and observations were made regarding how DAP recovers from them. Also the DAP flexibility to environment changes was watched. The experiments in the simulated environment confirmed the above features of DAP.

Teaching based on the case method of building collective protection

One of the fundamental aspects in the adaptation of the teaching to the European higher education is changing based models of teacher education to models based on student learning. In this work we present an educational experience developed with the teaching method based on the case method, with a clearly multidisciplinary. The experience has been developed in the teaching of analysis and verification of safety rails. This is a multidisciplinary field that presents great difficulties during their teaching. The use of the case method has given good results in the competences achieved by students

New methodology on Applied Geology and Geology for Engineers education by using practical trip

There has been much discussion on the primacy of theory over practice. Today prevails the exaggeration of practice. This idea forgets too that teaching problem is a problem of right balance. The approach of the action lines on the European Higher Education Area (EHEA) framework provides for such balance. Applied Geology subject represents the first real contact with the physical environment with the practice profession and works. Besides, the situation of the topic in the first trace of Study Plans for many students implies the link to other subjects and topics of the career. This work analyses in depth the justification of such practical trips only on Applied Geology. This methodology could be usual in Study Plans of pure sciences career, Geology or Biology, but not in Civil Engineering like teaching method. It shows the criteria and methods of planning and the result which manifests itself in pupils. Therefore, work shows a methodology taking in account the engineering perspective, the practical point of view and the learning process inside students and their evaluation and, hence, their marks.

Inter-Packet Symbol Approach To Reed-Solomon FEC Codes For RTP-Multimedia Stream Protection

This paper presents an alternative Forward Error Correction scheme, based on Reed-Solomon codes, with the aim of protecting the transmission of RTP-multimedia streams: the inter-packet symbol approach. This scheme is based on an alternative bit structure that allocates each symbol of the Reed-Solomon code in several RTP-media packets. This characteristic permits to exploit better the recovery capability of Reed-Solomon codes against bursty packet losses. The performance of our approach has been studied in terms of encoding/decoding time versus recovery capability, and compared with other proposed schemes in the literature. The theoretical analysis has shown that our approach allows the use of a lower size of the Galois Fields compared to other solutions. This lower size results in a decrease of the required encoding/decoding time while keeping a comparable recovery capability. Finally, experimental results have been carried out to assess the performance of our approach compared to other schemes in a simulated environment, where models for wireless and wireline channels have been considered.

Human-robot interaction for telemanipulation in large workspaces

Independientemente de la existencia de técnicas altamente sofisticadas y capacidades de cómputo cada vez más elevadas, los problemas asociados a los robots que interactúan con entornos no estructurados siguen siendo un desafío abierto en robótica. A pesar de los grandes avances de los sistemas robóticos autónomos, hay algunas situaciones en las que una persona en el bucle sigue siendo necesaria. Ejemplos de esto son, tareas en entornos de fusión nuclear, misiones espaciales, operaciones submarinas y cirugía robótica. Esta necesidad se debe a que las tecnologías actuales no pueden realizar de forma fiable y autónoma cualquier tipo de tarea. Esta tesis presenta métodos para la teleoperación de robots abarcando distintos niveles de abstracción que van desde el control supervisado, en el que un operador da instrucciones de alto nivel en la forma de acciones, hasta el control bilateral, donde los comandos toman la forma de señales de control de bajo nivel. En primer lugar, se presenta un enfoque para llevar a cabo la teleoperación supervisada de robots humanoides. El objetivo es controlar robots terrestres capaces de ejecutar tareas complejas en entornos de búsqueda y rescate utilizando enlaces de comunicación limitados. Esta propuesta incorpora comportamientos autónomos que el operador puede utilizar para realizar tareas de navegación y manipulación mientras se permite cubrir grandes áreas de entornos remotos diseñados para el acceso de personas. Los resultados experimentales demuestran la eficacia de los métodos propuestos. En segundo lugar, se investiga el uso de dispositivos rentables para telemanipulación guiada. Se presenta una aplicación que involucra un robot humanoide bimanual y un traje de captura de movimiento basado en sensores inerciales. En esta aplicación, se estudian las capacidades de adaptación introducidas por el factor humano y cómo estas pueden compensar la falta de sistemas robóticos de alta precisión. Este trabajo es el resultado de una colaboración entre investigadores del Biorobotics Laboratory de la Universidad de Harvard y el Centro de Automática y Robótica UPM-CSIC. En tercer lugar, se presenta un nuevo controlador háptico que combina velocidad y posición. Este controlador bilateral híbrido hace frente a los problemas relacionados con la teleoperación de un robot esclavo con un gran espacio de trabajo usando un dispositivo háptico pequeño como maestro. Se pueden cubrir amplias áreas de trabajo al cambiar automáticamente entre los modos de control de velocidad y posición. Este controlador háptico es ideal para sistemas maestro-esclavo con cinemáticas diferentes, donde los comandos se transmiten en el espacio de la tarea del entorno remoto. El método es validado para realizar telemanipulación hábil de objetos con un robot industrial. Por último, se introducen dos contribuciones en el campo de la manipulación robótica. Por un lado, se presenta un nuevo algoritmo de cinemática inversa, llamado método iterativo de desacoplamiento cinemático. Este método se ha desarrollado para resolver el problema cinemático inverso de un tipo de robot de seis grados de libertad donde una solución cerrada no está disponible. La eficacia del método se compara con métodos numéricos convencionales. Además, se ha diseñado una taxonomía robusta de agarres que permite controlar diferentes manos robóticas utilizando una correspondencia, basada en gestos, entre los espacios de trabajo de la mano humana y de la mano robótica. El gesto de la mano humana se identifica mediante la lectura de los movimientos relativos del índice, el pulgar y el dedo medio del usuario durante las primeras etapas del agarre. ABSTRACT Regardless of the availability of highly sophisticated techniques and ever increasing computing capabilities, the problems associated with robots interacting with unstructured environments remains an open challenge. Despite great advances in autonomous robotics, there are some situations where a humanin- the-loop is still required, such as, nuclear, space, subsea and robotic surgery operations. This is because the current technologies cannot reliably perform all kinds of task autonomously. This thesis presents methods for robot teleoperation strategies at different levels of abstraction ranging from supervisory control, where the operator gives high-level task actions, to bilateral teleoperation, where the commands take the form of low-level control inputs. These strategies contribute to improve the current human-robot interfaces specially in the case of slave robots deployed at large workspaces. First, an approach to perform supervisory teleoperation of humanoid robots is presented. The goal is to control ground robots capable of executing complex tasks in disaster relief environments under constrained communication links. This proposal incorporates autonomous behaviors that the operator can use to perform navigation and manipulation tasks which allow covering large human engineered areas of the remote environment. The experimental results demonstrate the efficiency of the proposed methods. Second, the use of cost-effective devices for guided telemanipulation is investigated. A case study involving a bimanual humanoid robot and an Inertial Measurement Unit (IMU) Motion Capture (MoCap) suit is introduced. Herein, it is corroborated how the adaptation capabilities offered by the human-in-the-loop factor can compensate for the lack of high-precision robotic systems. This work is the result of collaboration between researchers from the Harvard Biorobotics Laboratory and the Centre for Automation and Robotics UPM-CSIC. Thirdly, a new haptic rate-position controller is presented. This hybrid bilateral controller copes with the problems related to the teleoperation of a slave robot with large workspace using a small haptic device as master. Large workspaces can be covered by automatically switching between rate and position control modes. This haptic controller is ideal to couple kinematic dissimilar master-slave systems where the commands are transmitted in the task space of the remote environment. The method is validated to perform dexterous telemanipulation of objects with a robotic manipulator. Finally, two contributions for robotic manipulation are introduced. First, a new algorithm, the Iterative Kinematic Decoupling method, is presented. It is a numeric method developed to solve the Inverse Kinematics (IK) problem of a type of six-DoF robotic arms where a close-form solution is not available. The effectiveness of this IK method is compared against conventional numerical methods. Second, a robust grasp mapping has been conceived. It allows to control a wide range of different robotic hands using a gesture based correspondence between the human hand space and the robotic hand space. The human hand gesture is identified by reading the relative movements of the index, thumb and middle fingers of the user during the early stages of grasping.

Redes VSAT con el estándar DVB-S

Actualmente las redes VSAT (Very Small Aperture Terminal) están adquiriendo una mayor importancia en las comunicaciones por satélite debido a las nuevas aplicaciones que se están desarrollando tanto a nivel empresarial como a nivel de usuario final. El presente proyecto pretende hacer un estudio de este tipo de red para presentarla como una solución al problema de querer conectar estaciones dispersas, que por el perfil del terreno hace difícil la conexión de las mismas a través de las redes terrestres convencionales. Los nuevos estándares están haciendo que este tipo de redes proliferen muy deprisa ya que se consigue una mayor flexibilidad que con los estándares precedentes para este tipo de red. En concreto, en este proyecto se ha estudiado el estándar abierto DVB-S desarrollado por el grupo de trabajo DVB por ser uno de los más aceptado internacionalmente. Para comprender este sistema de comunicaciones, el proyecto está estructurado en dos partes. En la primera parte se hace una revisión de cómo han evolucionado las comunicaciones satelitales VSAT, indicando las ventajas y desventajas de su implementación y sobre todo la orientación que éstas muestran a la utilización de los estándares DVB. Posteriormente se realiza un estudio de los estándares DVB-S y DVBRCS en donde se profundiza en conceptos claves tales como el Multiplexado de Transporte MPEG-2, los mecanismos de envío de mensajes de señalización, etc. En la segunda parte del proyecto se presta atención a la seguridad de la red, analizando los mecanismos propios que presenta el estándar DVB así como los diferentes protocolos de seguridad existentes en las capas superiores para una protección adicional. Para concluir el proyecto se han creado dos aplicaciones, la primera como método didáctico para comprender mejor el comportamiento de las redes VSAT con el estándar DVB-S, y una segunda aplicación con carácter comercial para la transferencia de ficheros de manera segura con características específicas, enfocada particularmente en redes VSAT, aunque siendo posible su uso en otras redes. ABSTRACT. Nowadays VSAT networks (Very Small Aperture Terminal) are becoming more important in satellite communications, due to several new applications that are being developed both at company level and end user level. This project aims to make a study of this type of network to present it as a solution to the problem of wanting to connect scattered stations, because the terrain profile makes difficult to connect them via conventional terrestrial networks. New standards are making that such networks proliferate very quickly for the reason that a more flexibility than the previous standards for this type of network is achieved. Specifically, this project has studied the open standard DVB-S developed by the DVB workgroup as one of the most internationally accepted. To understand this communication system, this project is structured in two different parts: On one hand, in the first part a review about how VSAT satellite communications have evolved, indicating the advantages and disadvantages of its implementation and above all, the guidance that they show to the use of the DVB standards. Subsequently, a study of the DVB-S and DVB-RCS standards is developed, where delves into key concepts such as MPEG-2 Multiplexed Transport, mechanisms of transmission of signaling messages, etc. On the other hand, in the second part of the project, we focus on network security, analyzing the mechanisms presented by the DVB standard and various existing security protocols in the upper layers for an extra protection. To complete the project two different applications have been developed: the first one as a teaching method to better understand the behavior of VSAT networks in DVB-S standard, and the second one with a commercial basis for transferring files securely with specific features applications focused particularly in VSAT networks, although with a possible use on other networks.

An autostereoscopic device for mobile applications based on a liquid crystal microlens array and an OLED display

In recent years, many experimental and theoretical research groups worldwide have actively worked on demonstrating the use of liquid crystals (LCs) as adaptive lenses for image generation, waveform shaping, and non-mechanical focusing applications. In particular, important achievements have concerned the development of alternative solutions for 3D vision. This work focuses on the design and evaluation of the electro-optic response of a LC-based 2D/3D autostereoscopic display prototype. A strategy for achieving 2D/3D vision has been implemented with a cylindrical LC lens array placed in front of a display; this array acts as a lenticular sheet with a tunable focal length by electrically controlling the birefringence. The performance of the 2D/3D device was evaluated in terms of the angular luminance, image deflection, crosstalk, and 3D contrast within a simulated environment. These measurements were performed with characterization equipment for autostereoscopic 3D displays (angular resolution of 0.03 ).

Cross-analysis of Transversal Competences in Project Management

This paper presents a framework for project management competence assessment based on participant’s performance and contribution in a simulated environment. The proposed framework considers competence assessment through evidences and the participation of different roles. The system enforces the assessment of individual competences by means of a set of performance indicators. A specific case study is presented and the relationship between exhibited transversal competences and project quality is analysed.

Uso de una red inalámbrica de sensores para estimar riesgo de incendio

Una red inalámbrica de sensores (Wireless Sensor Network, WSN) constituye un sistema de comunicación de datos flexible utilizado como alternativa a las redes cableadas o como extensión de éstas y está compuesta por elementos de cómputo, medición y comunicación, que permiten al administrador instrumentar, observar y reaccionar a eventos y fenómenos en un ambiente específico. Una de las aplicaciones de estas redes es su uso en sistemas de predicción y prevención de incendios en áreas naturales. Su implementación se basa en el despliegue de sensores inalámbricos, realizado en una zona de riesgo de incendio para que puedan recolectar información sobre parámetros ambientales como temperatura, humedad, luz o presión, entre otros. Desde una estación base (o nodo "sumidero"), se suministra la información de los sensores a un centro de monitorización y control de forma estructurada. En este centro la información recibida puede ser analizada, procesada y visualizada en tiempo real. Desde este centro de control se puede controlar también la red WSN modificando el comportamiento de los sensores según el nivel de riesgo de incendio detectado. Este proyecto se basa en el diseño, implementación y despliegue de una red inalámbrica de sensores en un entorno simulado para observar su comportamiento en diferentes situaciones y mostrar su eficacia ante un posible caso de incendio. La implementación de este sistema denominado Sistema de Estimación de Riesgo de Incendio Utilizando una WSN (SERIUW) , junto con el desarrollado, en paralelo, de otro proyecto denominado Sistema de Control y Visualización de Información sobre Riesgo de Incendio (SCVIRI) que implementa las funciones de los centros de monitorización y control, conforman un Sistema de Anticipación y Seguimiento de Fuegos (SASF). Se han realizado pruebas de funcionalidad y eficacia, incluidas en la presente memoria del sistema unitario de en conjunto (ambos proyectos), en un entorno controlado simulado. Este sistema es una solución para la lucha contra los incendios forestales ya que predice y previene, de forma temprana, posibles incendios en las áreas naturales bajo supervisión. Ante un evento de incendio declarado este sistema es un poderoso instrumento de apoyo permitiendo, por un lado, generar alertas automáticas (con localización y gravedad de fuegos detectados) y por el otro, hacer un seguimiento del incendio con mapas en tiempo real (con su consecuente apoyo para la protección e información con las brigadas de bomberos en las zonas activas). ABSTRACT. A wireless sensor network (WSN) is a flexible data communication system used as an alternative to wired networks or as an extension of them and consists of nodes that perform calculation, measurement and communication activities. This allows the administrator to observe and react to events and phenomena in a specific environment. One application of these networks is fire prediction and prevention in natural areas. Its implementation is based on a deployment of wireless sensors, in a fire risk area, capable of collecting information such as temperature, humidity, luminance and pressure. A base station (or "sink") sends the collected information to a monitoring and control center following a structured format. At this center, the information received can be analyzed, processed and displayed in real time with monitoring systems. From this control center the WSN can also be controlled by changing the sensors behavior according to the level of fire risk detection. This project is based on the design, implementation and deployment of a Wireless Sensor Network (WSN) in a simulated environment in order to observe its behavior in different situations and show its effectiveness against a possible fire environment. The implementation of this system called SERIUW, has been done in parallel with other system, called SCVIRI, which has been developed in another project that implements the functions of monitoring and control center. Together, these two systems, make up a general system of anticipation and monitoring of fires. Functionality and performance tests have been performed on the overall system, in a controlled and simulated environment. The results of these tests are included in this document. The global system is a solution to fight the forest fires because it makes it easier to predict and prevent, early, possible fires in natural areas under supervision. This sytem can be a powerful tool since, before a fire event is declared, it generates automatic alerts (including location and severity information) and allows the real-time motorization of fire evolution integrated with maps. This could be also very useful for the support protection and information of fire brigades in zones in which a fire is already active.

Sistema de control y visualización de información sobre riesgo de incendios

Una red inalámbrica de sensores (Wireless Sensor Network, WSN) constituye un sistema de comunicación de datos flexible utilizado como alternativa a las redes cableadas o como extensión de éstas. Una de las aplicaciones de estas redes es para su uso en sistemas de predicción y prevención de incendios en áreas naturales. Su implementación se basa en el despliegue de sensores inalámbricos, realizado en una zona de riesgo de incendio que puedan recolectar información tal como temperatura, humedad y presión. Desde una estación base (o nodo "sumidero"), se suministra la información de los sensores a un centro de monitorización y control de forma estructurada. En estos centros la información recibida puede ser analizada, procesada y visualizada en tiempo real. Desde este centro de control se puede controlar también la red WSN modificando el comportamiento de los sensores según el nivel de riesgo de incendio detectado. Este proyecto se basa en el diseño, desarrollo e implementación de un Sistema de Control y Visualización de Información sobre Riesgo de Incendio (SCVIRI), que implementa las funciones de los centros de monitorización y control. La implementación de este sistema, junto con el desarrollado, en paralelo, de otro proyecto denominado Sistema de Estimación de Riesgo de Incendio Utilizando una WSN (SERIUW) que implementa la emulación de la red WSN, conforman un sistema general de anticipación y seguimiento de Fuegos. Se han realizado pruebas de funcionalidad y eficacia, incluidas en la presente memoria del sistema general (ambos proyectos), en un entorno controlado simulado. Este sistema es una solución para la lucha contra los incendios forestales ya que predice y previene, de forma temprana, posibles incendios en las áreas naturales bajo supervisión. Ante un evento de incendio declarado este sistema es un poderoso instrumento de apoyo permitiendo, por un lado, generar alertas automáticas (con localización y gravedad de fuegos detectados) y por el otro, hacer un seguimiento del incendio con mapas en tiempo real (con su consecuente apoyo para la protección e información con las brigadas de bomberos en las zonas activas). ABSTRACT. A wireless sensor network (WSN) is a flexible data communication system used as an alternative to wired networks or as an extension of them. One possible application of these networks is related to fire prediction and prevention in natural areas. Its implementation is based on a deployment of wireless sensors, in an area with high or moderate fire risk, to collect information such as temperature, humidity, luminance and pressure. A base station (or "sink") sends the collected information to a monitoring and control center according to an agreed structured format. At this center, the information received can be analyzed, processed and displayed in real time by using monitoring systems. From this control center the WSN can also be controlled by changing the sensors behavior in consistence with the detected level of fire risk. The work carried out in this project consists on the design, development and implementation of a system named SCVIRI, which implements the functions of the aforementioned monitoring and control center. This system works in connection with other one, called SERIUW, which has been developed in a different project and implements the WSN in an emulated environment. These two systems working together make up a general system of anticipation and monitoring of fires. This document also includes the functionality and performance tests performed on the overall system in a controlled and simulated environment. The global system is a solution that makes it easier to predict and prevent possible fires in natural areas under supervision. This system can be a powerful tool since, before a fire event is declared, it generates automatic alerts (including location and severity information) and allows the real-time motorization of fire evolution and its graphical visualization on maps. This could be also very useful for providing fire brigades with support, protection and information in zones in which a fire is already active.

A Novel Method for Radio Propagation Simulation Based on Automatic 3D Environment Reconstruction

In this paper, a novel method to simulate radio propagation is presented. The method consists of two steps: automatic 3D scenario reconstruction and propagation modeling. For 3D reconstruction, a machine learning algorithm is adopted and improved to automatically recognize objects in pictures taken from target regions, and 3D models are generated based on the recognized objects. The propagation model employs a ray tracing algorithm to compute signal strength for each point on the constructed 3D map. Our proposition reduces, or even eliminates, infrastructure cost and human efforts during the construction of realistic 3D scenes used in radio propagation modeling. In addition, the results obtained from our propagation model proves to be both accurate and efficient

A novel method for radio propagation simulation based on automatic 3D environment reconstruction

In this paper, a novel method to simulate radio propagation is presented. The method consists of two steps: automatic 3D scenario reconstruction and propagation modeling. For 3D reconstruction, a machine learning algorithm is adopted and improved to automatically recognize objects in pictures taken from target region, and 3D models are generated based on the recognized objects. The propagation model employs a ray tracing algorithm to compute signal strength for each point on the constructed 3D map. By comparing with other methods, the work presented in this paper makes contributions on reducing human efforts and cost in constructing 3D scene; moreover, the developed propagation model proves its potential in both accuracy and efficiency.

Analysis of teaching experience based on teaching by the case method. Application to reinforcing wooden floors

The technique of reinforcement of wooden floors is a matter clearly multidisciplinary. The teaching of the subject using the "traditional" method, explaining the theory first and then proposing and solving problems has not been successful. This paper discusses the results of a teaching experiencie. It has been the teaching of the subject by the case method. The results are clearly superior to those obtained with the traditional methodology.