Erfahrbares Programmieren durch den zielgerichten Einsatz von Flugdrohnen im Informatikunterricht

Informatik- und insbesondere Programmierunterricht sind heute ein wichtiger Bestandteil der schulischen Ausbildung. Vereinfachte Entwicklungsumgebungen, die auf die Abstraktion typischer Programmierkonzepte in Form von grafischen Bausteinen setzen, unterstützen diesen Trend. Zusätzliche Attraktivität wird durch die Verwendung exotischer Laufzeitumgebungen (z. B. Roboter) geschaffen. Die in diesem Paper vorgestellte Plattform “ScratchDrone” führt ergänzend zu diesen Angeboten eine moderne Flugdrohne als innovative Laufzeitumgebung für Scratch-Programme ein. Die Programmierung kann dabei dank modularer Systemarchitektur auf verschiedenen Abstraktionsebenen erfolgen, abhängig vom Lernfortschritt der Schüler. Kombiniert mit einem mehrstufigen didaktischen Modell, der Herausforderung der Bewegung im 3D-Raum sowie der natürlichen menschlichen Faszination für das Fliegen wird so eine hohe Lernmotivation bei jungen Programmieranfängern erreicht.

Aeronautical Information Geoservices

Aeronautical charts underlie the representation of aeronautic geographic information that supports pilots in flight. Nevertheless, charts become complex due to the high density of data and the different kinds that support each phase of flight. These features make difficult using them on board. After conducting a study that aims to understand and to evaluate pilot’s needs related to Geographic Information, it is proposed a solution to implement a platform based on geographic information standards (OGC, ISO) and supported by a distributed Web architecture. This platform facilitates the use, retrieval, updating of information and its exchange among different institutions through private and public users. As a first element to ensure interoperability and the harmonisation of information, we propose an aeronautical metadata profile that sets guidelines and elements for its description. This profile meets the standards set by ICAO, Eurocontrol and ISO. The platform offers three levels of access to data through different types of devices and user profiles. This paper suggests an alternative and reliable way for distributing aeronautical geoinformation, focusing on specific functions or displaying and querying.

Geoservices for Aeronautical Navigation

Aeronautical charts underlie the representation of aeronautic geographic information that supports pilots in flight. Nevertheless, the charts become complex due to the high density of data and the different kinds of charts that support each phase of flight. These features make difficult using them on board. After conducting a study, with civil Spaniard pilots, that aims to understand and to evaluate their needs related to Geographic Information, it is proposed a solution to implement a platform based on geographic information standards (OGC, ISO) and supported by a distributed Web architecture. This platform facilitates the use, retrieval, updating of information and its exchange among different institutions through private and public users. As a first element to ensure interoperability of information, we suggest an aeronautical metadata profile that sets guidelines and elements for its description. The metadata profile meets the standards set by ICAO, Eurocontrol and ISO. The platform offers three levels of access to data through different types of devices and user profiles. Thus, aeronautical institutions could edit data while pilot is on board accessing digital aeronautical charts through a laptop or Table PC. This paper suggests an alternative and reliable way for distributing aeronautical geoinformation, focusing on specific functions or displaying and querying.

Enhanced Failure Detection Mechanism in MapReduce

The popularity of MapReduce programming model has increased interest in the research community for its improvement. Among the other directions, the point of fault tolerance, concretely the failure detection issue seems to be a crucial one, but that until now has not reached its satisfying level. Motivated by this, I decided to devote my main research during this period into having a prototype system architecture of MapReduce framework with a new failure detection service, containing both analytical (theoretical) and implementation part. I am confident that this work should lead the way for further contributions in detecting failures to any NoSQL App frameworks, and cloud storage systems in general.

Riding out of the storm: How to deal with the complexity of grid and cloud management

Over the last decade, Grid computing paved the way for a new level of large scale distributed systems. This infrastructure made it possible to securely and reliably take advantage of widely separated computational resources that are part of several different organizations. Resources can be incorporated to the Grid, building a theoretical virtual supercomputer. In time, cloud computing emerged as a new type of large scale distributed system, inheriting and expanding the expertise and knowledge that have been obtained so far. Some of the main characteristics of Grids naturally evolved into clouds, others were modified and adapted and others were simply discarded or postponed. Regardless of these technical specifics, both Grids and clouds together can be considered as one of the most important advances in large scale distributed computing of the past ten years; however, this step in distributed computing has came along with a completely new level of complexity. Grid and cloud management mechanisms play a key role, and correct analysis and understanding of the system behavior are needed. Large scale distributed systems must be able to self-manage, incorporating autonomic features capable of controlling and optimizing all resources and services. Traditional distributed computing management mechanisms analyze each resource separately and adjust specific parameters of each one of them. When trying to adapt the same procedures to Grid and cloud computing, the vast complexity of these systems can make this task extremely complicated. But large scale distributed systems complexity could only be a matter of perspective. It could be possible to understand the Grid or cloud behavior as a single entity, instead of a set of resources. This abstraction could provide a different understanding of the system, describing large scale behavior and global events that probably would not be detected analyzing each resource separately. In this work we define a theoretical framework that combines both ideas, multiple resources and single entity, to develop large scale distributed systems management techniques aimed at system performance optimization, increased dependability and Quality of Service (QoS). The resulting synergy could be the key 350 J. Montes et al. to address the most important difficulties of Grid and cloud management.

Introducing usability in a conceptual modeling-based software development process.

Usability plays an important role to satisfy users? needs. There are many recommendations in the HCI literature on how to improve software usability. Our research focuses on such recommendations that affect the system architecture rather than just the interface. However, improving software usability in aspects that affect architecture increases the analyst?s workload and development complexity. This paper proposes a solution based on model-driven development. We propose representing functional usability mechanisms abstractly by means of conceptual primitives. The analyst will use these primitives to incorporate functional usability features at the early stages of the development process. Following the model-driven development paradigm, these features are then automatically transformed into subsequent steps of development, a practice that is hidden from the analyst.

Procedimiento de diseño acústico y eletroacústico de sistemas tipo

El presente proyecto propone la creación de un procedimiento y metodología para el diseño de salas y sistemas electroacústicos basados en el software EASE. La sala tipo elegida para el diseño será una sala de cine bajo las premisas de DOLBY Digital. Los sistemas electroacústicos modelo serán: • Sistema distribuido tanto en malla cuadrada como hexagonal • Sistemas centralizados basados en agrupaciones, tanto lineales como circulares. Se establecerán los pasos básicos imprescindibles para el diseño de los sistemas descritos de forma que, con la ayuda de este tutorial y los medios didácticos adjuntos al mismo, se puedan acometer paso a paso las distintas fases de diseño, cálculo y análisis de los mismos. Como metodología de trabajo se acometerá el proceso de diseño de un ejemplo de cada tipo sobre el que se describirán todos los pasos, posibilidades de diseño y cálculo de los mismos. Los puntos de estudio serán: • Diseño de una sala de Cine ◦Importación de los Ficheros Autocad del cine a EASE ◦Dibujo del recinto en EASE ◦Inserción de materiales ◦Cálculo del tiempo de reverberación en función del volumen de la sala ◦Ajuste del tiempo de reverberación ◦Elección de altavoces para la sonorización ◦Comprobación de la uniformidad de campo sonoro en todos los canales ◦Comprobación de los niveles de pico y total por canal ◦Ecualización de la sala según la curva X (ISO-2969) ◦Inclusión de la Pantalla en la curva de ecualización ◦Estudios psicoacústico de la sala. Retardos ◦Inteligibilidad ◦Diagrama de bloques • Diseño de un sistema distribuido ◦Estudio de los diferentes tipos de solapamientos ▪Borde con Borde ▪Solapamiento mínimo ▪Centro con Centro ◦Estudio de los diferente tipos de mallas ▪Cuadrada ▪Hexagonal • Diseño de un sistema Centralizado ◦Sistemas centralizados tipo Linear Array ◦Sistemas centralizados tipo Circular Array Así mismo se estudiarán las diferentes posibilidades dentro de la suite EASE, incluyendo las versiones gratuitas del mismo EASE ADDRESS (sistemas distribuidos) y FOCUS II (sistemas centralizados), comparando sus posibilidades con los módulos comerciales equivalentes de EASE y las herramientas añadidas del mismo EARS (software para la auralización biaural) y AURA (utilidad de análisis extendido). ABSTRACT This project proposes the creation of a procedure and methodology for the design of rooms and electroacoustic systems based on EASE software. The room chosen as example design is a cinema under DOLBY Digital premises. Electroacoustic systems chosen as example are: • Distributed both square and hexagonal mesh • Centralized systems based on clusters, both linear and circular. It will be established the basic essential steps for the design of the systems described so, with this tutorial and attached teaching aids, could be undertaken the various stages of design, calculation and analysis. As a working methodology, the process design of an example will be described of each system on which all the steps described, design possibilities and calculation will be shown. The main points are: • Design of a cinema • Importing Autocad Files in EASE • Drawing with EASE • Materials insertion • Reverberation time based on the room volume • Adjusting reverberation time • Choosing speakers • Checking sound field uniformity in all channels • Checking peak levels and total level per each channel • Room equalization using X curve (ISO-2969) • Adding screen in the EQ • Psychoacoustic. Delays • Intelligibility • Block diagram • Design of a distributed system • Study of the different types of overlap o Edge to Edge o Minimum Overlap o Center to Center • Study of different types of mesh • Square • Hex • Centralized System Design • Centralized systems. Linear Array • Centralized systems. Circular Array It also will explore the different possibilities within the EASE suite, including the free versions of the same EASE ADDRESS (distributed systems) and FOCUS II (centralized), comparing its potential with commercial equivalents EASE modules and added tools EARS (software for biaural auralization) and AURA (utility extended analysis).

Meter data management for smart monitoring power networks

The electrical power distribution and commercialization scenario is evolving worldwide, and electricity companies, faced with the challenge of new information requirements, are demanding IT solutions to deal with the smart monitoring of power networks. Two main challenges arise from data management and smart monitoring of power networks: real-time data acquisition and big data processing over short time periods. We present a solution in the form of a system architecture that conveys real time issues and has the capacity for big data management.

Including functional usability features in a Model-Driven Development Method

The Software Engineering (SE) community has historically focused on working with models to represent functionality and persistence, pushing interaction modelling into the background, which has been covered by the Human Computer Interaction (HCI) community. Recently, adequately modelling interaction, and specifically usability, is being considered as a key factor for success in user acceptance, making the integration of the SE and HCI communities more necessary. If we focus on the Model-Driven Development (MDD) paradigm, we notice that there is a lack of proposals to deal with usability features from the very first steps of software development process. In general, usability features are manually implemented once the code has been generated from models. This contradicts the MDD paradigm, which claims that all the analysts? effort must be focused on building models, and the code generation is relegated to model to code transformations. Moreover, usability features related to functionality may involve important changes in the system architecture if they are not considered from the early steps. We state that these usability features related to functionality can be represented abstractly in a conceptual model, and their implementation can be carried out automatically.

A scalable approach for content based image retrieval in cloud datacenter

The emergence of cloud datacenters enhances the capability of online data storage. Since massive data is stored in datacenters, it is necessary to effectively locate and access interest data in such a distributed system. However, traditional search techniques only allow users to search images over exact-match keywords through a centralized index. These techniques cannot satisfy the requirements of content based image retrieval (CBIR). In this paper, we propose a scalable image retrieval framework which can efficiently support content similarity search and semantic search in the distributed environment. Its key idea is to integrate image feature vectors into distributed hash tables (DHTs) by exploiting the property of locality sensitive hashing (LSH). Thus, images with similar content are most likely gathered into the same node without the knowledge of any global information. For searching semantically close images, the relevance feedback is adopted in our system to overcome the gap between low-level features and high-level features. We show that our approach yields high recall rate with good load balance and only requires a few number of hops.

Impedance-based stability and transient-performance assessment applying maximum peak criteria

The impedance-based stability-assessment method has turned out to be a very effective tool and its usage is rapidly growing in different applications ranging from the conventional interconnected dc/dc systems to the grid-connected renewable energy systems. The results are sometime given as a certain forbidden region in the complex plane out of which the impedance ratio--known as minor-loop gain--shall stay for ensuring robust stability. This letter discusses the circle-like forbidden region occupying minimum area in the complex plane, defined by applying maximum peak criteria, which is well-known theory in control engineering. The investigation shows that the circle-like forbidden region will ensure robust stability only if the impedance-based minor-loop gain is determined at the very input or output of each subsystem within the interconnected system. Experimental evidence is provided based on a small-scale dc/dc distributed system.

Diseño de una arquitectura escalable y de alta disponibilidad para un sistema middleware

El objetivo de este proyecto es el estudio de soluciones de escalabilidad y alta disponibilidad en sistemas distribuidos, así como su implantación en aquel de los sistemas analizados por Telefónica Digital, PopBox y Rush, que se consideré más adecuado. Actualmente, muchos servicios y aplicaciones están alojados directamente en laWeb, permitiendo abaratar el uso de ciertos servicios y mejorando la productividad y la competitividad de las empresas que los usan. Este crecimiento de las tecnologías en cloud experimentado en los últimos años plantea la necesidad de realizar sistemas que sean escalables, fiables y estén disponibles la mayor parte del tiempo posible. Un fallo en el servicio no afecta a una sola empresa, sino a todas las que están haciendo uso de dicho servicio. A lo largo de este proyecto se estudiarán las soluciones de alta disponibilidad y escalabilidad implementadas en varios sistemas distribuidos y se realizará una evaluación crítica de cada una de ellas. También se analizará la idoneidad de estas soluciones para los sistemas en los que posteriormente se aplicarán: PopBox y Rush. Se han diseñado diferentes soluciones para las plataformas implicadas, siguiendo varias aproximaciones y realizando un análisis exhaustivo de cada una de ellas, teniendo en cuenta el rendimiento y fiabilidad de cada aproximación. Una vez se ha determinado cuál es la estrategia más adecuada, se ha realizado una implementación fiable del sistema. Para cada uno de los módulos implementados se ha llevado a cabo una fase de testing unitario y de integración para asegurar el buen comportamiento del sistema y la integridad de éste cuando se realicen cambios. Específicamente, los objetivos que se alcanzarán son los siguientes: 1. Análisis exhaustivo de los sistemas de escalabilidad y alta escalabilidad que existen actualmente. 2. Diseño de una solución general HA1 y escalable teniendo en cuenta el objetivo anterior. 3. Análisis de la idoneidad de los sistemas PopBox y Rush para el diseño de un entorno distribuido escalable. 4. Diseño e implantación de una solución ad-hoc en el sistema elegido. ---ABSTRACT---The aim of this project is the study of solutions in scalability and high availability in distributed systems, and also its implementation in one of the systems developed y Telefónica I+D, PopBox and Rush, deemed more suitable. Nowadays, a lot of services and applications are stored directly in the Web, allowing companies to reduce the costs of using certain services and improving the productivity and competitiveness of those who use these services. This increase of the use of cloud tecnologies experimented in the last few years has led to the need of developing high available, scalable, and reliable systems. A failure in the service does not affect a single company but all the companies using this service. Throughout this project, I will study several solutions in High Availability and Scalability developed in some distributed systems and I will make a critic analysis of each one. Also I will analize the suitability of these solutions in the systems in which they will be applied: PopBox and Rush. I have designed different solutions for the platforms involved, following several approaches and making an exhaustive analysis of each one, taking into account their performance and reliability of each approach. Once I had determined which is the best strategy, I have developed a reliable implementation of the system. For each module implemented, I have carried out a set of unitary and integration tests to ensure the good behaviour of the system and the integrity of it when it changes. Specifically, the objectives to be achieved are as follows: 1. Exhaustive analysis of the systems in scalability and high availability that currently exist. 2. Design of a general solution taking into account the previous point. 3. Analysis of the suitability of the sistems PopBox and Rush for the design of a scalable distributed system. 4. Design and implementation of an ad-hoc solution in the chosen system.

Implementación de sistema domótico con servidor Raspberry

Este proyecto consiste en el diseño e implementación un sistema domótico que puede ser instalado en una vivienda para controlar distintas variables ambientales y conseguir así la máxima comodidad de los habitantes de manera automática o manual según los gustos y necesidades de los usuarios. La característica principal de este sistema, es que cuenta con un funcionamiento distribuido donde entran en juego un servidor, encargado de tomar las decisiones generales para el comportamiento de la casa, y una serie de controladores esclavo cuya función es mantener constantes las variables ambientales con los valores fijados por el servidor. Así se consigue mantener la vivienda en una situación de bienestar constante para cualquier persona que se encuentre dentro. El sistema ha sido pensado de manera que se intenta reducir al máximo el cableado para facilitar su instalación por lo que la comunicación entre los distintos dispositivos se hace de manera inalámbrica por medio de un protocolo descrito en la norma IEEE 802.15.4 llamado ZigBee. Para ello se ha utilizado un módulo de comunicación wireless llamado Xbee, el cual permite la comunicación entre dos dispositivos. Para el control de dicho sistema distribuido se cuenta con una aplicación web, que mediante una interfaz gráfica permite al usuario controlar los distintos dispositivos dentro de la vivienda consiguiendo así controlar las variables ambientales a gusto del usuario. Dicha interfaz gráfica no depende de un software específico, sino que sólo es necesario un cliente http como podría ser Internet Explorer, Mozilla Firefox, Google Chrome, etc. Para integrar dicho sistema se ha usado un mini ordenador de bajo coste llamado RaspBerryPi, en el que se encuentra alojado un servidor Apache con el fin de gestionar y automatizar las variables ambientales. El control de los dipositivos encargados de modificar y estabilizar las variables ambientales se realiza mediante unos controladores genéricos implementados mediante mcontroladores 80C51F410, pertenecientes a la familia 80C51, y una serie de componentes y circuitería que permiten el correcto funcionamiento de éstos. Existen dos tipos de controladores distintos, los cuales son: Controlador Sensor: Encargados de las tomas de valores ambientales como puede ser la luz y la temperatura. Controladores Actuadores: Encargados de actuar sobre los dispositivos que modifican y estabilizan las variables ambientales como pueden ser la calefacción, tiras de leds de iluminación, persianas, alarmas, etc. El conjunto de la RaspBerryPi y los diferentes controladores forman el prototipo diseñado para este proyecto fin de carrera, el cual puede ser ampliado sencillamente para abarcar una amplia gama de posibilidades y funcionalidades dentro de la comodidad de una vivienda. ABSTRACT. The project described in this report consisted designing and implementing a home automation system that could be installed in a house in order to control environmental variables and thus get the maximum comfort of the inhabitant automatically or manually according to their tastes and needs. The main feature of this system consists in a distributed system, formed by a server which is responsible for making the main decisions of the actions performed inside the house. In addition, there are a series of slave controlers whose function consists in keeping the environmental variables within the values established by the server. Thus gets to keep the home in a situation of constant wellbeing to anyone who is inside. The system has been designed in order to reduce the amount of wire needed for the inter-connection of the devices, by means of wireless communication. The devices chosen for the solution are Xbee modules, which use the Zigbee protocol in order to comunicate one between each other. The Zigbee protocol is fully described in the IEEE 802.15.4 standard. A web application has been used to control the distributed system. This application allows users to control various devices inside the house and subsequently the different environmental variables. This implementation allows obtaining the maximum comfort by means of a very simple graphical interface. In addition, the Graphical User Interface (GUI) does not depend on any specific software. This means that it would only be necessary a http client (such as Internet Explorer, Mozilla Firefox, Google Chrome, etc.) for handling the application. The system has been integrated using a low-cost mini computer called RaspBerryPi.This computer has an Apache server allocated which allows to manage and to automatize the different environmental variables. Furthermore, for changing and stabilizing those variables, some generic controllers have been developed, based on mcontrollers 80C51F410. There have been developed mainly two different types of controllers: Sensor Controllers, responsible for measuring the different environmental values, such as light and temperature; and Actuator Controllers, which purpose is to modify and stabilize those environmental variables by actuating on the heating, the led lamps, the blinders, the alarm, etc. The combination of the RaspBerryPi and the different controllers conform the prototype designed during this project. Additionally, this solution could be easily expanded in order to intake further functionalities adapted to new needs that could arise in the future.

A tool assisting teachers in automating the assessment of programming assignments

Automating the assessment of programming assignments brings benefits for both students and teachers, since it helps the formers to gain a timely feedback and releases the latter from tedious tasks. The related literature in the domain has usually focused on the assessment process and the tools required for it, proposing libraries and systems that teachers can use in this process. However, few of them have work rowards reducing the effort and time teacher require to properly set up new assessente processes. This paper describes our experience with the analysis and design of a new tool to support teachers in visually developing automatic grades of programming assignments, introducing the underlying concepts and technologies and presenting the system architecture.

High brightness semiconductor lasers as transmitters for space lidar systems

High brightness semiconductor lasers are potential transmitters for future space lidar systems. In the framework of the European Project BRITESPACE, we propose an all-semiconductor laser source for an Integrated Path Differential Absorption lidar system for column-averaged measurements of atmospheric CO2 in future satellite missions. The complete system architecture has to be adapted to the particular emission properties of these devices using a Random Modulated Continuous Wave approach. We present the initial experimental results of the InGaAsP/InP monolithic Master Oscillator Power Amplifiers, providing the ON and OFF wavelengths close to the selected absorption line around 1572 nm.