A speech interface for air traffic control terminals

Several issues concerning the current use of speech interfaces are discussed and the design and development of a speech interface that enables air traffic controllers to command and control their terminals by voice is presented. A special emphasis is made in the comparison between laboratory experiments and field experiments in which a set of ergonomics-related effects are detected that cannot be observed in the controlled laboratory experiments. The paper presents both objective and subjective performance obtained in field evaluation of the system with student controllers at an air traffic control (ATC) training facility. The system exhibits high word recognition test rates (0.4% error in Spanish and 1.5% in English) and low command error (6% error in Spanish and 10.6% error in English in the field tests). Subjective impression has also been positive, encouraging future development and integration phases in the Spanish ATC terminals designed by Aeropuertos Españoles y Navegación Aérea (AENA).

Probabilistic versus incremental presynaptic learning in biological plausible synapses

In this paper, the presynaptic rule, a classical rule for hebbian learning, is revisited. It is shown that the presynaptic rule exhibits relevant synaptic properties like synaptic directionality, and LTP metaplasticity (long-term potentiation threshold metaplasticity). With slight modifications, the presynaptic model also exhibits metaplasticity of the long-term depression threshold, being also consistent with Artola, Brocher and Singer’s (ABS) influential model. Two asymptotically equivalent versions of the presynaptic rule were adopted for this analysis: the first one uses an incremental equation while the second, conditional probabilities. Despite their simplicity, both types of presynaptic rules exhibit sophisticated biological properties, specially the probabilistic version

Berth Management in Container Terminals: Quality of Service

This paper empirically evaluates container terminal service attributes. The methodology proposed focuses on statistical control. Based on the concept of service segmentation, the authors employed control charts to classify container terminal services. The purpose of control charts is to allow simple detection of events that are indicative of actual process change. This simple decision can be difficult where the process characteristic is continuously varying, the control chart provides statistically objective criteria of change. When change is detected and considered good its cause should be identified and possibly become the new way of working, where the change is bad then its cause should be identified and eliminated. Both theoretical and practical implications of the research findings are discussed in this paper.

Berth management in container terminals: quality of service

This paper empirically evaluates container terminal service attributes. The methodology proposed focuses on statistical control. Based on the concept of service segmentation, we employed control charts to classify container terminal services. The purpose of control charts is to allow simple detection of events that are indicative of actual process change. This simple decision can be difficult where the process characteristic is continuously varying; the control chart provides statistically objective criteria of change. When change is detected and considered good its cause should be identified and possibly become the new way of working, where the change is bad then its cause should be identified and eliminated. This paper is organized as follows: Section 1 is the introduction, Section 2 provides a brief note on other studies that inspired this research, section 3 focuses on the methodology used, and develops the results obtained and finally conclusions are shown in Section 4. Theoretical and practical implications of the research findings are discussed.

A methodology proposal to obtain operational parameter forecasts and operational risk assessment in container terminals

Las terminales de contenedores son sistemas complejos en los que un elevado número de actores económicos interactúan para ofrecer servicios de alta calidad bajo una estricta planificación y objetivos económicos. Las conocidas como "terminales de nueva generación" están diseñadas para prestar servicio a los mega-buques, que requieren tasas de productividad que alcanzan los 300 movimientos/ hora. Estas terminales han de satisfacer altos estándares dado que la competitividad entre terminales es elevada. Asegurar la fiabilidad de las planificaciones del atraque es clave para atraer clientes, así como reducir al mínimo el tiempo que el buque permanece en el puerto. La planificación de las operaciones es más compleja que antaño, y las tolerancias para posibles errores, menores. En este contexto, las interrupciones operativas deben reducirse al mínimo. Las principales causas de dichas perturbaciones operacionales, y por lo tanto de incertidumbre, se identifican y caracterizan en esta investigación. Existen una serie de factores que al interactuar con la infraestructura y/o las operaciones desencadenan modos de fallo o parada operativa. Los primeros pueden derivar no solo en retrasos en el servicio sino que además puede tener efectos colaterales sobre la reputación de la terminal, o incluso gasto de tiempo de gestión, todo lo cual supone un impacto para la terminal. En el futuro inmediato, la monitorización de las variables operativas presenta gran potencial de cara a mejorar cualitativamente la gestión de las operaciones y los modelos de planificación de las terminales, cuyo nivel de automatización va en aumento. La combinación del criterio experto con instrumentos que proporcionen datos a corto y largo plazo es fundamental para el desarrollo de herramientas que ayuden en la toma de decisiones, ya que de este modo estarán adaptadas a las auténticas condiciones climáticas y operativas que existen en cada emplazamiento. Para el corto plazo se propone una metodología con la que obtener predicciones de parámetros operativos en terminales de contenedores. Adicionalmente se ha desarrollado un caso de estudio en el que se aplica el modelo propuesto para obtener predicciones de la productividad del buque. Este trabajo se ha basado íntegramente en datos proporcionados por una terminal semi-automatizada española. Por otro lado, se analiza cómo gestionar, evaluar y mitigar el efecto de las interrupciones operativas a largo plazo a través de la evaluación del riesgo, una forma interesante de evaluar el effecto que eventos inciertos pero probables pueden generar sobre la productividad a largo plazo de la terminal. Además se propone una definición de riesgo operativo junto con una discusión de los términos que representan con mayor fidelidad la naturaleza de las actividades y finalmente, se proporcionan directrices para gestionar los resultados obtenidos. Container terminals are complex systems where a large number of factors and stakeholders interact to provide high-quality services under rigid planning schedules and economic objectives. The socalled next generation terminals are conceived to serve the new mega-vessels, which are demanding productivity rates up to 300 moves/hour. These terminals need to satisfy high standards because competition among terminals is fierce. Ensuring reliability in berth scheduling is key to attract clients, as well as to reduce at a minimum the time that vessels stay the port. Because of the aforementioned, operations planning is becoming more complex, and the tolerances for errors are smaller. In this context, operational disturbances must be reduced at a minimum. The main sources of operational disruptions and thus, of uncertainty, are identified and characterized in this study. External drivers interact with the infrastructure and/or the activities resulting in failure or stoppage modes. The later may derive not only in operational delays but in collateral and reputation damage or loss of time (especially management times), all what implies an impact for the terminal. In the near future, the monitoring of operational variables has great potential to make a qualitative improvement in the operations management and planning models of terminals that use increasing levels of automation. The combination of expert criteria with instruments that provide short- and long-run data is fundamental for the development of tools to guide decision-making, since they will be adapted to the real climatic and operational conditions that exist on site. For the short-term a method to obtain operational parameter forecasts in container terminals. To this end, a case study is presented, in which forecasts of vessel performance are obtained. This research has been entirely been based on data gathered from a semi-automated container terminal from Spain. In the other hand it is analyzed how to manage, evaluate and mitigate disruptions in the long-term by means of the risk assessment, an interesting approach to evaluate the effect of uncertain but likely events on the long-term throughput of the terminal. In addition, a definition for operational risk evaluation in port facilities is proposed along with a discussion of the terms that better represent the nature of the activities involved and finally, guidelines to manage the results obtained are provided.

On the Biological Plausibility of Artificial Metaplasticity

The training algorithm studied in this paper is inspired by the biological metaplasticity property of neurons. Tested on different multidisciplinary applications, it achieves a more efficient training and improves Artificial Neural Network Performance. The algorithm has been recently proposed for Artificial Neural Networks in general, although for the purpose of discussing its biological plausibility, a Multilayer Perceptron has been used. During the training phase, the artificial metaplasticity multilayer perceptron could be considered a new probabilistic version of the presynaptic rule, as during the training phase the algorithm assigns higher values for updating the weights in the less probable activations than in the ones with higher probability

Stability and Transient Performance Assessment in a COTS-Module-Based Distributed DC/DC System

This paper introduces a method to analyze and predict stability and transient performance of a distributed system where COTS (Commercial-off-the-shelf) modules share an input filter. The presented procedure is based on the measured data from the input and output terminals of the power modules. The required information for the analysis is obtained by performing frequency response measurements for each converter. This attained data is utilized to compute special transfer functions, which partly determine the source and load interactions within the converters. The system level dynamic description is constructed based on the measured and computed transfer functions introducing cross-coupling mechanisms within the system. System stability can be studied based on the well-known impedance- related minor-loop gain at an arbitrary interface within the system.

Energy/power consumption model for an embedded processor board

This dissertation, whose research has been conducted at the Group of Electronic and Microelectronic Design (GDEM) within the framework of the project Power Consumption Control in Multimedia Terminals (PCCMUTE), focuses on the development of an energy estimation model for the battery-powered embedded processor board. The main objectives and contributions of the work are summarized as follows: A model is proposed to obtain the accurate energy estimation results based on the linear correlation between the performance monitoring counters (PMCs) and energy consumption. the uniqueness of the appropriate PMCs for each different system, the modeling methodology is improved to obtain stable accuracies with slight variations among multiple scenarios and to be repeatable in other systems. It includes two steps: the former, the PMC-filter, to identify the most proper set among the available PMCs of a system and the latter, the k-fold cross validation method, to avoid the bias during the model training stage. The methodology is implemented on a commercial embedded board running the 2.6.34 Linux kernel and the PAPI, a cross-platform interface to configure and access PMCs. The results show that the methodology is able to keep a good stability in different scenarios and provide robust estimation results with the average relative error being less than 5%. Este trabajo fin de máster, cuya investigación se ha desarrollado en el Grupo de Diseño Electrónico y Microelectrónico (GDEM) en el marco del proyecto PccMuTe, se centra en el desarrollo de un modelo de estimación de energía para un sistema empotrado alimentado por batería. Los objetivos principales y las contribuciones de esta tesis se resumen como sigue: Se propone un modelo para obtener estimaciones precisas del consumo de energía de un sistema empotrado. El modelo se basa en la correlación lineal entre los valores de los contadores de prestaciones y el consumo de energía. Considerando la particularidad de los contadores de prestaciones en cada sistema, la metodología de modelado se ha mejorado para obtener precisiones estables, con ligeras variaciones entre escenarios múltiples y para replicar los resultados en diferentes sistemas. La metodología incluye dos etapas: la primera, filtrado-PMC, que consiste en identificar el conjunto más apropiado de contadores de prestaciones de entre los disponibles en un sistema y la segunda, el método de validación cruzada de K iteraciones, cuyo fin es evitar los sesgos durante la fase de entrenamiento. La metodología se implementa en un sistema empotrado que ejecuta el kernel 2.6.34 de Linux y PAPI, un interfaz multiplataforma para configurar y acceder a los contadores. Los resultados muestran que esta metodología consigue una buena estabilidad en diferentes escenarios y proporciona unos resultados robustos de estimación con un error medio relativo inferior al 5%.

Integración MPlayer-OpenSVC en el procesador multinúcleo OMAP3530

La constante evolución de dispositivos portátiles multimedia que se ha producido en la última década ha provocado que hoy en día se disponga de una amplia variedad de dispositivos con capacidad para reproducir contenidos multimedia. En consecuencia, la reproducción de esos contenidos en dichos terminales lleva asociada disponer de procesadores que soporten una alta carga computacional, ya que las tareas de descodificación y presentación de video así lo requieren. Sin embargo, un procesador potente trabajando a elevadas frecuencias provoca un elevado consumo de la batería, y dado que se pretende trabajar con dispositivos portátiles, la vida útil de la batería se convierte en un asunto de especial importancia. La problemática que se plantea se ha convertido en una de las principales líneas de investigación del Grupo de Investigación GDEM (Grupo de Diseño Electrónico y Microelectrónico). En esta línea de trabajo, se persigue cómo optimizar el consumo de energía en terminales portables desde el punto de vista de la reducción de la calidad de experiencia del usuario a cambio de una mayor autonomía del terminal. Por tanto, para lograr esa reducción de la calidad de experiencia mencionada, se requiere un estándar de codificación de vídeo que así lo permita. El Grupo de Investigación GDEM cuenta con experiencia en el estándar de vídeo escalable H.264/SVC, el cual permite degradar la calidad de experiencia en función de las necesidades/características del dispositivo. Más concretamente, un video escalable contiene embebidas distintas versiones del video original que pueden ser descodificadas en diferentes resoluciones, tasas de cuadro y calidades (escalabilidades espacial, temporal y de calidad respectivamente), permitiendo una adaptación rápida y muy flexible. Seleccionado el estándar H.264/SVC para las tareas de vídeo, se propone trabajar con Mplayer, un reproductor de vídeos de código abierto (open source), al cual se le ha integrado un descodificador para vídeo escalable denominado OpenSVC. Por último, como dispositivo portable se trabajará con la plataforma de desarrollo BeagleBoard, un sistema embebido basado en el procesador OMAP3530 que permite modificar la frecuencia de reloj y la tensión de alimentación dinámicamente reduciendo de este modo el consumo del terminal. Este procesador a su vez contiene integrados un procesador de propósito general (ARM Cortex-A8) y un procesador digital de señal (DSP TMS320C64+TM). Debido a la alta carga computacional de la descodificación de vídeos escalables y la escasa optimización del ARM para procesamiento de datos, se propone llevar a cabo la ejecución de Mplayer en el ARM y encargar la tarea de descodificación al DSP, con la finalidad de reducir el consumo y por tanto aumentar la vida útil del sistema embebido sobre el cual se ejecutará la aplicación desarrollada. Una vez realizada esa integración, se llevará a cabo una caracterización del descodificador alojado en el DSP a través de una serie de medidas de rendimiento y se compararán los resultados con los obtenidos en el proceso de descodificación realizado únicamente en el ARM. ABSTRACT During the last years, the multimedia portable terminals have gradually evolved causing that nowadays a several range of devices with the ability of playing multimedia contents are easily available for everyone. Consequently, those multimedia terminals must have high-performance processors to play those contents because the coding and decoding tasks demand high computational load. However, a powerful processor performing to high frequencies implies higher battery consumption, and this issue has become one of the most important problems in the development cycle of a portable terminal. The power/energy consumption optimization on multimedia terminals has become in one the most significant work lines in the Electronic and Microelectronic Research Group of the Universidad Politécnica de Madrid. In particular, the group is researching how to reduce the user‟s Quality of Experience (QoE) quality in exchange for increased battery life. In order to reduce the Quality of Experience (QoE), a standard video coding that allows this operation is required. The H.264/SVC allows reducing the QoE according to the needs/characteristics of the terminal. Specifically, a scalable video contains different versions of original video embedded in an only one video stream, and each one of them can be decoded in different resolutions, frame rates and qualities (spatial, temporal and quality scalabilities respectively). Once the standard video coding is selected, a multimedia player with support for scalable video is needed. Mplayer has been proposed as a multimedia player, whose characteristics (open-source, enormous flexibility and scalable video decoder called OpenSVC) are the most suitable for the aims of this Master Thesis. Lastly, the embedded system BeagleBoard, based on the multi-core processor OMAP3530, will be the development platform used in this project. The multimedia terminal architecture is based on a commercial chip having a General Purpose Processor (GPP – ARM Cortex A8) and a Digital Signal Processor (DSP, TMS320C64+™). Moreover, the processor OMAP3530 has the ability to modify the operating frequency and the supply voltage in a dynamic way in order to reduce the power consumption of the embedded system. So, the main goal of this Master Thesis is the integration of the multimedia player, MPlayer, executed at the GPP, and scalable video decoder, OpenSVC, executed at the DSP in order to distribute the computational load associated with the scalable video decoding task and to reduce the power consumption of the terminal. Once the integration is accomplished, the performance of the OpenSVC decoder executed at the DSP will be measured using different combinations of scalability values. The obtained results will be compared with the scalable video decoding performed at the GPP in order to show the low optimization of this kind of architecture for decoding tasks in contrast to DSP architecture.

Exploration of RVC applications using an ARM multicore processor = Exploración de aplicaciones RVC empleando un procesador ARM multinúcleo

Single core capabilities have reached their maximum clock speed; new multicore architectures provide an alternative way to tackle this issue instead. The design of decoding applications running on top of these multicore platforms and their optimization to exploit all system computational power is crucial to obtain best results. Since the development at the integration level of printed circuit boards are increasingly difficult to optimize due to physical constraints and the inherent increase in power consumption, development of multiprocessor architectures is becoming the new Holy Grail. In this sense, it is crucial to develop applications that can run on the new multi-core architectures and find out distributions to maximize the potential use of the system. Today most of commercial electronic devices, available in the market, are composed of embedded systems. These devices incorporate recently multi-core processors. Task management onto multiple core/processors is not a trivial issue, and a good task/actor scheduling can yield to significant improvements in terms of efficiency gains and also processor power consumption. Scheduling of data flows between the actors that implement the applications aims to harness multi-core architectures to more types of applications, with an explicit expression of parallelism into the application. On the other hand, the recent development of the MPEG Reconfigurable Video Coding (RVC) standard allows the reconfiguration of the video decoders. RVC is a flexible standard compatible with MPEG developed codecs, making it the ideal tool to integrate into the new multimedia terminals to decode video sequences. With the new versions of the Open RVC-CAL Compiler (Orcc), a static mapping of the actors that implement the functionality of the application can be done once the application executable has been generated. This static mapping must be done for each of the different cores available on the working platform. It has been chosen an embedded system with a processor with two ARMv7 cores. This platform allows us to obtain the desired tests, get as much improvement results from the execution on a single core, and contrast both with a PC-based multiprocessor system. Las posibilidades ofrecidas por el aumento de la velocidad de la frecuencia de reloj de sistemas de un solo procesador están siendo agotadas. Las nuevas arquitecturas multiprocesador proporcionan una vía de desarrollo alternativa en este sentido. El diseño y optimización de aplicaciones de descodificación de video que se ejecuten sobre las nuevas arquitecturas permiten un mejor aprovechamiento y favorecen la obtención de mayores rendimientos. Hoy en día muchos de los dispositivos comerciales que se están lanzando al mercado están integrados por sistemas embebidos, que recientemente están basados en arquitecturas multinúcleo. El manejo de las tareas de ejecución sobre este tipo de arquitecturas no es una tarea trivial, y una buena planificación de los actores que implementan las funcionalidades puede proporcionar importantes mejoras en términos de eficiencia en el uso de la capacidad de los procesadores y, por ende, del consumo de energía. Por otro lado, el reciente desarrollo del estándar de Codificación de Video Reconfigurable (RVC), permite la reconfiguración de los descodificadores de video. RVC es un estándar flexible y compatible con anteriores codecs desarrollados por MPEG. Esto hace de RVC el estándar ideal para ser incorporado en los nuevos terminales multimedia que se están comercializando. Con el desarrollo de las nuevas versiones del compilador específico para el desarrollo de lenguaje RVC-CAL (Orcc), en el que se basa MPEG RVC, el mapeo estático, para entornos basados en multiprocesador, de los actores que integran un descodificador es posible. Se ha elegido un sistema embebido con un procesador con dos núcleos ARMv7. Esta plataforma nos permitirá llevar a cabo las pruebas de verificación y contraste de los conceptos estudiados en este trabajo, en el sentido del desarrollo de descodificadores de video basados en MPEG RVC y del estudio de la planificación y mapeo estático de los mismos.

Criterios de calidad del servicio prestado en el ámbito de la línea de atraque de las terminales portuarias de contenedores

Esta Tesis Doctoral evalúa empíricamente la calidad del servicio en la línea de atraque de las terminales portuarias de contenedores. La metodología propuesta utiliza indicadores de calidad y se basa en el concepto de la segmentación de servicio. Para ello se desarrolla la teoría del Control Estadístico de Procesos (CEP) y se utilizan los gráficos de control para clasificar el servicio en las terminales de contenedores. El propósito de la Tesis es proporcionar una metodología basada en el Control Estadístico de Procesos (CEP) para evaluar la calidad del servicio y detectar las escalas de un servicio regular de línea que se encuentran fuera de control. Por tanto, la metodología se puede utilizar para detectar eventos que son indicativos de cambio real del proceso en la línea de atraque. Esta detección puede ser compleja pues las características de los procesos en terminales de contenedores son variables. La metodología proporciona mediante los gráficos de control criterios estadísticamente objetivos de cambio. Cuando el cambio es detectado y considerado bueno sus causas deben ser identificadas y posiblemente convertirse en la nueva forma de trabajar, cuando el cambio es negativo, entonces sus causas deberían ser identificadas y eliminadas. La Tesis Doctoral está organizado de la siguiente manera: La primera parte es la introducción, e incluye los capítulos 1 al 4, la segunda parte presenta el Estado del Arte (capítulo 5) y algunos de los estudios que han inspirado esta investigación, la tercera parte se centra en la metodología utilizada (capítulo 6) y su aplicación sobre un caso de estudio (capítulo 7). Finalmente, en la cuarta parte se presentan las conclusiones y se proponen algunas de las nuevas líneas de investigación que quedan abiertas (capítulo 8). This Thesis empirically evaluates the quality of service in the berthing face of container terminals. The methodology proposed is focused on quality of service indicators and is based on the concept of service segmentation. The Statistical Process Control (SPC) theory and the control charts are used to classify container terminal service. The aim of this Thesis is to provide a methodology based on Statistical Process Control that can evaluate the quality of service and also can detect scales of shipping liner service that are out of control. Therefore, the methodology can be used to detect events that are indicative of real change in the berthing process of container vessels. The methodology proposed allows simple detection of events that are indicative of actual process change in container terminals. This detection is complex because the characteristics of the processes are variable in the container terminals; the control chart provides statistically objective criteria of change. When change is detected and considered good its cause should be identified and possibly become the new way of working, where the change is bad then its cause should be identified and eliminated. This Thesis is organized as follows: The first part is the introduction (includes Chapters 1 to 4), the second part presents the State of the Art (Chapter 5) and some of the studies that have inspired this research. The third part focuses on the methodology used (Chapter 6) and its application to a case study (Chapter 7). Finally, Part 4 presents the conclusions and suggests future research (Chapter 8).

Container Terminal Simulation. A case study: port of Valencia.

This paper is concerned with the study of non-Markovian queuing systems in container terminals. The methodology presented has been applied to analyze the ship traffic in the port of Valencia located in the Western Mediterranean. Two container terminals have been studied: the public container terminal of NOATUM and the dedicated container terminal of MSC. This paper contains the results of a simulation model based on queuing theory. The methodology presented is found to be effective in replicating realistic ship traffic operations in port as well as in conducting capacity evaluations. Thus the methodology can be used for capacity planning (long term), tactical planning (medium term) and even for the container terminal design (port enlargement purposes).

Análisis de las diversas metodologías para el estudio del sistema de atraque en terminales portuarias

This paper is concerned with the study of the berth system in port terminals. The main objective is to present the management methodologies, which include empirical methods, analytical methods and simulation methods The comparison shows that these three methods are not independent, but they are complementary. Each method has advantages and limitations and these depend on the type of study performed.

Wireless Optical Communications for Intra-Spacecraft Networks Based on OCDMA with Random Optical Codes

In recent years, spacial agencies have shown a growing interest in optical wireless as an alternative to wired and radio-frequency communications. The use of these techniques for intra-spacecraft communications reduces the effect of take-off acceleration and vibrations on the systems by avoiding the need for rugged connectors and provides a significant mass reduction. Diffuse transmission also eases the design process as terminals can be placed almost anywhere without a tight planification to ensure the proper system behaviour. Previous studies have compared the performance of radio-frequency and infrared optical communications. In an intra-satellite environment optical techniques help reduce EMI related problems, and their main disadvantages - multipath dispersion and the need for line-of-sight - can be neglected due to the reduced cavity size. Channel studies demonstrate that the effect of the channel can be neglected in small environments if data bandwidth is lower than some hundreds of MHz.

A new feature extraction method for signal classification applied to cat spinal cord signals

In the spinal cord of the anesthetized cat, spontaneous cord dorsum potentials (CDPs) appear synchronously along the lumbo-sacral segments. These CDPs have different shapes and magnitudes. Previous work has indicated that some CDPs appear to be specially associated with the activation of spinal pathways that lead to primary afferent depolarization and presynaptic inhibition. Visual detection and classification of these CDPs provides relevant information on the functional organization of the neural networks involved in the control of sensory information and allows the characterization of the changes produced by acute nerve and spinal lesions. We now present a novel feature extraction approach for signal classification, applied to CDP detection. The method is based on an intuitive procedure. We first remove by convolution the noise from the CDPs recorded in each given spinal segment. Then, we assign a coefficient for each main local maximum of the signal using its amplitude and distance to the most important maximum of the signal. These coefficients will be the input for the subsequent classification algorithm. In particular, we employ gradient boosting classification trees. This combination of approaches allows a faster and more accurate discrimination of CDPs than is obtained by other methods.