12 resultados para out of control

em Universidad Politécnica de Madrid


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Ubiquitous computing (one person, many computers) is the third era in the history of computing. It follows the mainframe era (many people, one computer) and the PC era (one person, one computer). Ubiquitous computing empowers people to communicate with services by interacting with their surroundings. Most of these so called smart environments contain sensors sensing users’ actions and try to predict the users’ intentions and necessities based on sensor data. The main drawback of this approach is that the system might perform unexpected or unwanted actions, making the user feel out of control. In this master thesis we propose a different procedure based on Interactive Spaces: instead of predicting users’ intentions based on sensor data, the system reacts to users’ explicit predefined actions. To that end, we present REACHeS, a server platform which enables communication among services, resources and users located in the same environment. With REACHeS, a user controls services and resources by interacting with everyday life objects and using a mobile phone as a mediator between himself/herself, the system and the environment. REACHeS’ interfaces with a user are built upon NFC (Near Field Communication) technology. NFC tags are attached to objects in the environment. A tag stores commands that are sent to services when a user touches the tag with his/her NFC enabled device. The prototypes and usability tests presented in this thesis show the great potential of NFC to build such user interfaces.

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In this paper, a novel and approach for obtaining 3D models from video sequences captured with hand-held cameras is addressed. We define a pipeline that robustly deals with different types of sequences and acquiring devices. Our system follows a divide and conquer approach: after a frame decimation that pre-conditions the input sequence, the video is split into short-length clips. This allows to parallelize the reconstruction step which translates into a reduction in the amount of computational resources required. The short length of the clips allows an intensive search for the best solution at each step of reconstruction which robustifies the system. The process of feature tracking is embedded within the reconstruction loop for each clip as opposed to other approaches. A final registration step, merges all the processed clips to the same coordinate frame

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Purpose Sustainable mobility urban policies intend reducing car use and increasing walking, cycling and public transport. However, this transfer from private car to these more sustainable modes is only a real alternative where distances are small and the public transport supply competitive enough. This paper proposes a methodology to calculate the number of trips that can be transferred from private car to other modes in city centres. Method The method starts analyzing which kind of trips cannot change its mode (purposes, conditions, safety , etc.), and then setting a process to determine under which conditions trips made by car between given O-D pairs can be transferable. Then, the application of demand models allow to determine which trips fulfil the transferability conditions. The process test the possibility of transfer in a sequential way: firs to walking, then cycling and finally to public transport. Results The methodology is tested through its application to the city of Madrid (Spain), with the result of only some 18% of the trips currently made by car could be made by other modes, under the same conditions of trip time, and without affecting their characteristics. Out of these trips, 75% could be made by public transport, 15% cycling and 10% on foot. The possible mode to be transferred depends on the location: city centre areas are more favourable for walking and cycling while city skirts could attract more PT trips. Conclusions The proposed method has demonstrated its validity to determine the potential of transferring trips out of cars to more sustainable modes. Al the same time it is clear that, even in areas with favourable conditions for walking, cycling and PT trips, the potential of transfer is limited because cars fulfil more properly special requirements of some trips and tours.

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One major problem of concurrent multi-path transfer (CMT) scheme in multi-homed mobile networks is that the utilization of different paths with diverse delays may cause packet reordering among packets of the same ?ow. In the case of TCP-like, the reordering exacerbates the problem by bringing more timeouts and unnecessary retransmissions, which eventually degrades the throughput of connections considerably. To address this issue, we ?rst propose an Out-of-order Scheduling for In-order Arriving (OSIA), which exploits the sending time discrepancy to preserve the in-order packet arrival. Then, we formulate the optimal traf?c scheduling as a constrained optimization problem and derive its closedform solution by our proposed progressive water-?lling solution. We also present an implementation to enforce the optimal scheduling scheme using cascaded leaky buckets with multiple faucets, which provides simple guidelines on maximizing the utilization of aggregate bandwidth while decreasing the probability of triggering 3 dupACKs. Compared with previous work, the proposed scheme has lower computation complexity and can also provide the possibility for dynamic network adaptability and ?ner-grain load balancing. Simulation results show that our scheme signi?cantly alleviates reordering and enhances transmission performance.

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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.

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It is clear that in the near future much broader transmissions in the HF band will replace part of the current narrow band links. Our personal view is that a real wide band signal is infeasible in this environment because the usage is typically very intensive and may suffer interferences from all over the world. Therefore, we envision that dynamic multiband transmissions may provide better satisfactory performance. From the very beginning, we observed that real links with our broadband transceiver suffered interferences out of our multiband but within the acquisition bandwidth that degrade the expected performance. Therefore, we concluded that a mitigation structure is required that operates on severely saturated signals as the interference may be of much higher power. In this paper we address a procedure based on Higher Order Crossings (HOC) statistics that are able to extract most of the signal structure in the case where the amplitude is severely distorted and allows the estimation of the interference carrier frequency to command a variable notch filter that mitigates its effect in the analog domain.

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We envision that dynamic multiband transmissions taking advantage of the receiver diversity (even for collocated antennas with different polarization or radiation pattern) will create a new paradigm for these links guaranteeing high quality and reliability. However, there are many challenges to face regarding the use of broadband reception where several out of band (with respect to multiband transmission) strong interferers, but still within the acquisition band, may limit dramatically the expected performance. In this paper we address this problem introducing a specific capability of the communication system that is able to mitigate these interferences using analog beamforming principles. Indeed, Higher Order Crossing (HOCs) joint statistics of the Single Input ? Multiple Output (SIMO) system are shown to effectively determine the angle on arrival of the wavefront even operating over highly distorted signals.

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All the interconnected regulated systems are prone to impedance-based interactions making them sensitive to instability and transient-performance degradation. The applied control method affects significantly the characteristics of the converter in terms of sensitivity to different impedance interactions. This paper provides for the first time the whole set of impedance-type internal parameters and the formulas according to which the interaction sensitivity can be fully explained and analyzed. The formulation given in this paper can be utilized equally either based on measured frequency responses or on predicted analytic transfer functions. Usually, the distributed dc-dc systems are constructed by using ready-made power modules without having thorough knowledge on the actual power-stage and control-system designs. As a consequence, the interaction characterization has to be based on the frequency responses measureable via the input and output terminals. A buck converter with four different control methods is experimentally characterized in frequency domain to demonstrate the effect of control method on the interaction sensitivity. The presented analytical models are used to explain the phenomena behind the changes in the interaction sensitivity.

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Electric vehicles constitute a multidisciplinary subject that involves disciplines such as automotive, mechanical, electrical and control engineering. Due to this multidisciplinary technical nature, practical teaching methodologies are of special relevance. Paradoxically, in the past, the training of engineers specializing in this area has lacked the practical component represented by field tests, due to the difficulty of accessing real systems. This paper presents an educational project specifically designed for the teaching and training of engineering students with different backgrounds and experience. The teaching methodology focuses on the topology of electric traction drives and their control. It includes two stages, a simulation computer model and a scaled laboratory workbench that comprises a traction electrical drive coupled to a vehicle emulator. With this equipment, the effectiveness of different traction control strategies can be analyzed from the point of view of energy efficiency, robustness, easiness of implementation and acoustic noise.

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l objeto de este trabajo es investigar sobre la arquitectura futurista mediante la figura de Jan Kaplický, el cual realizó planteamientos y arquitecturas que todavía hoy son realmente innovadoras e impactantes, centrando el tema en sus propuestas de vanguardia sobre lo doméstico. La obra elegida para este análisis es la House for a Helicopter Pilot (1979), una arquitectura nómada y cinética en que se habitaría una cápsula modular que puede elevar o bajar sus brazos hidráulicos y luego, una vez cansado el usuario del entorno, podría abandonarlo y encontrar otro lugar salvaje en que situarse. Al ser una obra no construida y utópica, sobre la que no hay apenas documentación, se propone como objetivo indagar sobre esta arquitectura alternativa que hoy en día sigue resultando innovadora, y realizar hipótesis explorando los detalles y objetos que aparecen en la escasa documentación existente, profundizando en las ideas utópicas de Jan Kaplicky

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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).

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Son numerosos los expertos que predicen que hasta pasado 2050 no se utilizarán masivamente las energías de origen renovable, y que por tanto se mantendrá la emisión de dióxido de carbono de forma incontrolada. Entre tanto, y previendo que este tipo de uso se mantenga hasta un horizonte temporal aún más lejano, la captura, concentración y secuestro o reutilización de dióxido de carbono es y será una de las principales soluciones a implantar para paliar el problema medioambiental causado. Sin embargo, las tecnologías existentes y en desarrollo de captura y concentración de este tipo de gas, presentan dos limitaciones: las grandes cantidades de energía que consumen y los grandes volúmenes de sustancias potencialmente dañinas para el medioambiente que producen durante su funcionamiento. Ambas razones hacen que no sean atractivas para su implantación y uso de forma extensiva. La solución planteada en la presente tesis doctoral se caracteriza por la ausencia de residuos producidos en la operación de captura y concentración del dióxido de carbono, por no utilizar substancias químicas y físicas habituales en las técnicas actuales, por disminuir los consumos energéticos al carecer de sistemas móviles y por evitar la regeneración química y física de los materiales utilizados en la actualidad. Así mismo, plantea grandes retos a futuras innovaciones sobre la idea propuesta que busquen fundamentalmente la disminución de la energía utilizada durante su funcionamiento y la optimización de sus componentes principales. Para conseguir el objetivo antes citado, la presente tesis doctoral, una vez establecido el planteamiento del problema al que se busca solución (capítulo 1), del estudio de las técnicas de separación de gases atmosféricos utilizadas en la actualidad, así como del de los sistemas fundamentales de las instalaciones de captura y concentración del dióxido de carbono (capítulo 2) y tras una definición del marco conceptual y teórico (capítulo 3), aborda el diseño de un prototipo de ionización fotónica de los gases atmosféricos para su posterior separación electrostática, a partir del estudio, adaptación y mejora del funcionamiento de los sistemas de espectrometría de masas. Se diseñarán y desarrollarán los sistemas básicos de fotoionización, mediante el uso de fuentes de fotones coherentes, y los de separación electrostática (capítulo 4), en que se basa el funcionamiento de este sistema de separación de gases atmosféricos y de captura y concentración de dióxido de carbono para construir un prototipo a nivel laboratorio. Posteriormente, en el capítulo 5, serán probados utilizando una matriz experimental que cubra los rangos de funcionamiento previstos y aporte suficientes datos experimentales para corregir y desarrollar el marco teórico real, y con los que se pueda establecer y corregir un modelo físico– matemático de simulación (capítulo 6) aplicable a la unidad en su conjunto. Finalmente, debido a la utilización de unidades de ionización fotónica, sistemas láseres intensos y sistemas eléctricos de gran potencia, es preciso analizar el riesgo biológico a las personas y al medioambiente debido al impacto de la radiación electromagnética producida (capítulo 7), minimizando su impacto y cumpliendo con la legislación vigente. En el capítulo 8 se planteará un diseño escalable a tamaño piloto de la nueva tecnología propuesta y sus principales modos de funcionamiento, así como un análisis de viabilidad económica. Como consecuencia de la tesis doctoral propuesta y del desarrollo de la unidad de separación atmosférica y de captura y concentración de dióxido de carbono, surgen diversas posibilidades de estudio que pueden ser objeto de nuevas tesis doctorales y de futuros desarrollos de ingeniería. El capítulo 9 tratará de incidir en estos aspectos indicando líneas de investigación para futuras tesis y desarrollos industriales. ABSTRACT A large number of experts predict that until at least 2050 renewable energy sources will not be massively used, and for that reason, current Primary Energy sources based on extensive use of fossil fuel will be used maintaining out of control emissions, Carbon Dioxide above all. Meanwhile, under this scenario and considering its extension until at least 2050, Carbon Capture, Concentration, Storage and/or Reuse is and will be one of the main solutions to minimise Greenhouse Gasses environmental effect. But, current Carbon Capture and Storage technology state of development has two main problems: it is a too large energy consuming technology and during normal use it produces a large volume of environmentally dangerous substances. Both reasons are limiting its development and its extensive use. This Ph Degree Thesis document proposes a solution to get the expected effect using a new atmospheric gasses separation system with the following characteristics: absence of wastes produced, it needs no chemical and/or physical substances during its operation, it reduces to minimum the internal energy consumptions due to absence of mobile equipment and it does not need any chemical and/or physical regeneration of substances. This system is beyond the State of the Art of current technology development. Additionally, the proposed solution raises huge challenges for future innovations of the proposed idea finding radical reduction of internal energy consumption during functioning, as well as regarding optimisation of main components, systems and modes of operation. To achieve this target, once established the main problem, main challenge and potential solving solutions (Chapter 1), it is established an initial starting point fixing the Atmospheric Gasses Separation and Carbon Capture and Storage developments (Chapter 2), as well as it will be defined the theoretical and basic model, including existing and potential new governing laws and mathematical formulas to control its system functioning (Chapter 3), this document will deal with the design of an installation of an operating system based on photonic ionization of atmospheric gasses to be separated in a later separation system based on the application of electrostatic fields. It will be developed a basic atmospheric gasses ionization prototype based on intense radioactive sources capable to ionize gasses by coherent photonic radiation, and a basic design of electrostatic separation system (Chapter 4). Both basic designs are the core of the proposed technology that separates Atmospheric Gasses and captures and concentrates Carbon Dioxide. Chapter 5 will includes experimental results obtained from an experimental testing matrix covering expected prototype functioning regimes. With the obtained experimental data, theoretical model will be corrected and improved to act as the real physical and mathematical model capable to simulate real system function (Chapter 6). Finally, it is necessary to assess potential biological risk to public and environment due to the proposed use of units of intense energy photonic ionization, by laser beams or by non–coherent sources and large electromagnetic systems with high energy consumption. It is necessary to know the impact in terms of and electromagnetic radiation taking into account National Legislation (Chapter 7). On Chapter 8, an up scaled pilot plant will be established covering main functioning modes and an economic feasibility assessment. As a consequence of this PhD Thesis, a new field of potential researches and new PhD Thesis are opened, as well as future engineering and industrial developments (Chapter 9).