Type Assignement for Mobile Objects

Digitalitzat per Artypla

Multiple resource reuse for device-to-device communication in future cellular networks

Aufgrund der stärkeren Verbreitung neuer mobiler Anwendungen, z.B. Autonomes Fahren, automatisierte Prozesssteuerung, intelligente Städte / Wohnen und taktiles Internet, nimmt - die Anzahl und Dichte von Geräten, die drahtlose Verbindungen erfordern, immer weiter zu. Dies erfordert effizientere Verfahren zur Nutzung des verfügbaren Frequenzspektrums für zellulare Netze. Um dieser Herausforderung zu begegnen, wurden Ansätze, wie die gemeinsame Nutzung von Frequenzen, vorgeschlagen, um die gesamte spektrale Effizienz zu verbessern. Die Device-to-Device Kommunikation (D2D) mit paralleler Übertragung zu einem zellularen Netz bietet eine Verbesserung der spektralen Effizienz durch die verstärkte gemeinsame Nutzung des verfügbaren zellularen Spektrums. Mit D2D kommunizieren Geräte in unmittelbarer Nähe direkt miteinander ohne oder mit nur einer minimalen Kontrolle über das Mobilfunknetz. Das 3rd Generation Partnership Project (3GPP) unterstützt durch Standardisierung die Integration von D2D in Mobilfunknetze, um die spektralen Effizienzgewinne bei der gemeinsamen Nutzung von Frequenzen unter Gewährleistung der Quality of Service (QoS) zu realisieren. Die Interferenzen zwischen D2D und zellularen Benutzern müssen jedoch während der gemeinsamen Nutzung des Spektrums kontrolliert werden, um diese Gewinne im Netzwerk zu erhalten. Die vorliegende Arbeit untersucht Lösungen, mit denen das Frequenzspektrum des Mobilfunknetzes mit D2D-Benutzern geteilt werden kann, welche sowohl die spektrale Effizienz maximieren als auch die QoS-Anforderungen aller Benutzer erfüllen (in Bezug auf das Signal-zu-Rausch-plus-Interferenz Verhältnis (SINR)). Die vorliegende Arbeit gliedert sich in zwei Teile: eine analytische und eine algorithmische Studie. Zunächst untersucht die analytische Studie den Ansatz für ein Interferenzmanagement, in welchem mehrere D2D-Benutzer das zellulare Spektrum gemeinsam nutzen. Dabei wird die Zuteilung einer einheitlichen Interferenzleistung (UIP) vorgeschlagen - ein Verfahren, bei dem alle D2D-Benutzer mit gleicher Interferenz an der Basisstation (BS) beitragen. Dieses Schema wird auf ein Szenario einer einzelnen Zelle angewendet, welches sehr positive Ergebnisse bei der Verbesserung der spektralen Effizienz erzielt, obwohl einige D2D-Benutzer ihre SINR-Schwellenwerte nicht erreichen können. Eine wesentliche Erkenntnis aus der analytischen Studie ist, dass eine räumliche Trennung zwischen Benutzern, die das Spektrum gemeinsam nutzen, wichtig ist, um ihre gegenseitige Beeinflussung zu minimieren. Die algorithmische Studie konzentriert sich daher auf die Auswahl geeigneter D2D-Benutzern. Zunächst werden räumliche Auswahlkriterien formuliert mit dem Ziel, mehrere D2D-Benutzer zu identifizieren, die das Spektrum eines bestimmten Mobilfunkbenutzers gemeinsam nutzen können, um die spektrale Effizienz zu maximieren, während alle Benutzer ihre SINR-Schwellenwerte erreichen. Danach werden basierend auf diesen Kriterien zwei Auswahlalgorithmen entwickelt. Der erste Algorithmus wählt opportunistisch D2D-Benutzer aus, die bei bestimmten Auswahlinstanzen die geringste Störung für andere das Spektrum gemeinsam nutzende Benutzer verursachen. Der zweite Algorithmus wählt zufällig alle D2D-Benutzer aus, die räumliche von anderen Benutzern getrennt sind, jedoch das Spektrum gemeinsam nutzen. Beide Algorithmen werden mit sehr positiven Ergebnissen durch Simulationen in einem Szenario einer einzelnen Zelle mit einer unterschiedlichen Anzahl von Benutzern vorgestellt. In einem Szenario mit mehreren Zellen, in welchem die Interferenz zwischen den Zellen die Leistungsfähigkeit beeinträchtigt, werden Verbesserungen an beiden Algorithmen vorgestellt, um die festgelegten Ziele zu erreichen. Diese Verbesserungen passen die Auswahlkriterien an, um: 1) keine D2D-Benutzer mit Zellenkante auszuwählen und 2) die Auswirkungen der gemeinsamen Nutzung des Frequenzspektrums zwischen benachbarten Zellen zu berücksichtigen. Die Arbeit zeigt deutlich, dass mithilfe eines geeigneten Auswahlkriteriums mehrere D2D Nutzer in der Lage sind, die gemeinsame Frequenzressource mit zellularen Nutzern zu teilen mit Erhöhung der gesamten spektralen Effizienz und Beibehaltung der QoS Anforderungen aller Nutzer. Die hierbei erbrachten Erkenntnisse können zusammen mit den vorhandenen Ergebnissen als Ausgangspunkt für weitere akademische Forschung sowie einer praktischen Anwendung dienen.Owing to the further proliferation of new mobile applications, e.g. autonomous driving, automated process control, smart cities/homes, and tactile internet, the number and density of devices requiring wireless connectivity continue to increase. This demands ever more efficient methods for utilizing the available frequency spectrum for cellular networks. To counter this challenge, approaches like spectrum sharing have been proposed as enablers to improve the overall spectral efficiency. Device to device communication (D2D) as an underlaying transmission to the cellular network presents spectral efficiency improvements through the increased sharing of the available cellular spectrum. In D2D, devices in close proximity communicate directly with each other having either minimal or no control from the cellular network. The third generation partnership project (3GPP) supports, through standardization, the integration of D2D within cellular networks in order to realize the spectral efficiency gains during spectrum sharing and user quality of service (QoS) guarantees. However, the interference between D2D and cellular users during spectrum sharing must be controlled to get these gains in the network. This thesis studies the solutions through which the cellular network's frequency spectrum can be shared with D2D users to concurrently maximize the spectral efficiency and achieve all users' QoS requirements (in terms of threshold signal-to-interference-plus-noise ratio (SINR)). The thesis is divided into two parts: an analytical study and an algorithmic study. First, the analytical study evaluates the framework for interference management when several D2D users share the cellular network's spectrum. Therein, uniform interference power (UIP) allocation -- a scheme where all D2D users contribute equal interference at the base station (BS), is proposed. This scheme is applied to a single-cell scenario with very positive results in improving spectral efficiency although some D2D users are unable to achieve their threshold SINRs. The main lesson from the analytical study is that spatial separation between users sharing spectrum is important to minimize their mutual interference. So the algorithmic study focuses on D2D-users selection. First, spatial selection criteria are formulated with the objective of identifying multiple D2D users that can share a given cellular user's spectrum to maximize spectral efficiency while all users achieve their threshold SINRs. Thereafter, based on these criteria, two selection algorithms are developed. The first algorithm opportunistically selects D2D users causing the least interference, at given selection instances, to other users sharing the spectrum. The second algorithm randomly selects any D2D users meeting the minimal required spatial separation from other users sharing the spectrum. Both algorithms are presented with very positive results in simulations that consider a single-cell scenario with varying number of users. In a multi-cell scenario, where the experienced inter-cell interference degrades performance, enhancements to both algorithms are applied to achieve the set objectives. These enhancements adapt the selection criteria to: $1$) not select cell-edge D2D users and $2$) take into account the effects of spectrum sharing between neighbouring cells. The thesis studies clearly showed that, using appropriate selection criteria, multiple D2D users can share a specific cellular user's spectrum resources to improve the network's spectral efficiency and achieve all users' QoS requirements. These findings together with other existing results on D2D spectrum resource reuse can be the starting point for further academic research and practical implementation

Desarrollo dirigido por modelos de aplicaciones móviles multiplataforma a partir de un conjunto de reglas heurísticas basadas en esquemas preconceptuales

ilustraciones, diagramas, tablasModel driven development (MDD) approaches aim for increasing development team productivity and decreasing software time-to-market. Such approaches comprise a set of model-to-model and model-to-text transformation rules for generating the source code based on models. Some authors propose MDD approaches for cross-platform mobile applications. So, we perform a systematic literature review looking for MDD approaches for cross-platform mobile applications, having as a result 39 primary studies grouped on 19 different MDD approaches. We observe 100.0 % approaches lack close-to-natural modeling languages, 36.8 % approaches lack design patterns, and 84.2 % lack usability features. In addition, 42.1 % approaches use out-of-date programming languages as automation result. Therefore, we propose an MDD approach for cross-platform mobile applications by using pre-conceptual schemas. Such schemas allow for guaranteeing a close-to-natural modeling language, including design patterns, and including usability features. Moreover, we complete the UN-LEND specification language as an intermediate model between pre-conceptual schemas and cross-platform mobile applications, avoiding the usage of out-of-date programming languages. Then, we design a pre-conceptual-schema-based metamodel in order to develop an MDD prototype based on the Eclipse Modeling Framework and XPAND. We propose a set of heuristic rules divided into model, view, and controller layers, having the pre-conceptual schema as a rule left-hand side, UN-LEND as an intermediate model, and Java-Android and Swift-iOS code as a rule right-hand side. We validate our approach by using a case of study about MobileSQUARE: an Android application for requirements gathering based on a question answering model. As a result, we automatically generate 90.86 % of the MobileSQUARE application by using our approach. Specifically, we observe model layer is close to be fully automated having 98.95 % as automation percentage compared to view and controller layers with 82.31 % and 84.56 % respectively. We expect researchers and software engineering practitioners increase their productivity and decrease software time-to-market based on our results. We identify some future work and challenges such as: including Programming eXperience heuristics in the resulting code (PX); allowing round-trip transformations between code, UN-LEND, and pre-conceptual schemas; including rules related to pre-conceptual schema vectors, matrices, and achievement relationships; improving controller and view layers related rules to increase the automation percentage; developing a compiler for UN-LEND models.Los enfoques de desarrollo dirigidos por modelos (MDD) tienen como objetivo aumentar la productividad del equipo de desarrollo y reducir el tiempo de comercialización del software. Algunos autores proponen enfoques MDD para aplicaciones móviles multiplataforma. Por ello, se realiza una revisión sistemática de la literatura en busca de enfoques MDD para aplicaciones móviles multiplataforma, teniendo como resultado 39 estudios primarios agrupados en 19 enfoques MDD diferentes. Se observa que el 100,0 % de los enfoques carecen de lenguajes de modelado cercanos al natural, el 36,8 % de los enfoques carecen de patrones de diseño y el 84,2 % carecen de características de usabilidad. Además, el 42,1 % de los enfoques utilizan lenguajes de programación obsoletos como resultado de la automatización. Por lo tanto, se propone un enfoque MDD para aplicaciones móviles multiplataforma mediante el uso de esquemas preconceptuales. Estos esquemas permiten garantizar un lenguaje de modelado cercano al natural, incluir patrones de diseño e incluir características de usabilidad. Además, se completa el lenguaje de especificación UN-LEND como modelo intermedio entre los esquemas preconceptuales y las aplicaciones móviles multiplataforma, evitando el uso de lenguajes de programación desfasados. Luego, se diseña un metamodelo del esquema preconceptual para desarrollar un prototipo de MDD basado en el Eclipse Modeling Framework y XPAND. Se propone un conjunto de reglas heurísticas divididas en las capas modelo, vista, y controlador, teniendo al esquema preconceptual como el lado izquierdo de la regla, UN-LEND como modelo intermedio, y el código Android Java e iOS Swift como el lado derecho de la regla. Se valida este enfoque utilizando un caso de estudio sobre MobileSQUARE: una aplicación Android para la recopilación de requisitos basada en un modelo de respuesta a preguntas. Como resultado, se genera automáticamente el 90,86 % de la aplicación MobileS-QUARE utilizando las reglas propuestas. En concreto, se observa que la capa model está cerca de la automatización total teniendo un 98,95 % como porcentaje de automatización en comparación con las capas vista y controlador con un 82,31 % y 84,56 % respectivamente. Se espera que los investigadores y los profesionales de la ingeniería del software aumenten su productividad y reduzcan el tiempo de comercialización del software basándose en estos resultados. Como resultado de esta Tesis de Maestría, se identifican algunas propuestas y retos futuros como: incluir heurísticas de Experiencia del Programador (PX) en el código resultante; permitir las transformaciones de ida y vuelta entre código, UN-LEND y los esquemas preconceptuales; incluir reglas relacionadas con los vectores, la matrices y las relaciones de logro de los esquemas preconceptuales; y desarrollar un compilador para los modelos UN-LEND. (Texto tomado de la fuente)MaestríaMagister en Ingeniería - Ingeniería de SistemasSoftware engineeringÁrea Curricular de Ingeniería de Sistemas e Informátic

An Evidential Filter for Indoor Navigation of a Mobile Robot in Dynamic Environment

International audienceRobots are destined to live with humans and perform tasks for them. In order to do that, an adapted representation of the world including human detection is required. Evidential grids enable the robot to handle partial information and ignorance, which can be useful in various situations. This paper deals with an audiovisual perception scheme of a robot in indoor environment (apartment, house..). As the robot moves, it must take into account its environment and the humans in presence. This article presents the key-stages of the multimodal fusion: an evidential grid is built from each modality using a modified Dempster combination, and a temporal fusion is made using an evidential filter based on an adapted version of the generalized bayesian theorem. This enables the robot to keep track of the state of its environment. A decision can then be made on the next move of the robot depending on the robot's mission and the extracted information. The system is tested on a simulated environment under realistic conditions

Local measurements of nonlocal observables and the relativistic reduction process

In this paper we reconsider the constraints which are imposed by relativistic requirements to any model of dynamical reduction. We review the debate on the subject and we call attention on the fundamental contributions by Aharonov and Albert. Having done this we present a new formulation, which is much simpler and more apt for our analysis, of the proposal put forward by these authors to perform measurements of nonlocal observables by means of local interactions and detections. We take into account recently proposed relativistic models of dynamical reduction and we show that, in spite of some mathematical difficulties related to the appearence of divergences, they represent a perfectly appropriate conceptual framework which meets all necessary requirements for a relativistic account of wave packet reduction. Subtle questions like the appropriate way to deal with counterfactual reasoning in a relativistic and nonlocal context are also analyzed in detail

The coherence of EU trade, competition, and industry policies in the high tech sector : the case of the telecommunications services sector

We analyze the coherence existing among European Union competition, industry, and trade policies in the high tech sector in general terms focusing on its specific features (externalities, fast progress) and their effects on the emergence and treatment of policy consistency and conflicts. Second, this analysis is applied to the European telecommunications services sector. The examination of this sector and the relevant EU policies reveals a consensus on giving priority to competition. However structural factors prevent policy implementation to reflect much liberalization and harmonization and business responses to trade globalization challenge effective competition. The potential, important role of standardization is shown.economics of technology ;

Modules over Monads and Operational Semantics

This paper is a contribution to the search for efficient and high-level mathematical tools to specify and reason about (abstract) programming languages or calculi. Generalising the reduction monads of Ahrens et al., we introduce transition monads, thus covering new applications such as ???-calculus, ?-calculus, Positive GSOS specifications, differential ?-calculus, and the big-step, simply-typed, call-by-value ?-calculus. Finally, we design a suitable notion of signature for transition monads

Millimeter wave radar for SLAM applications

Lo scopo di questa tesi è quello di introdurre la tecnologia radar ad onde millimetriche applicata a problemi di mapping e di localizzazione in modo da investigare la fattibilità del recente concetto di "personal radar". Più specificatamente, può essere inteso come una caratteristica futura degli apparecchi mobili per la stima delle mappe degli ambienti interni sfruttando le tecnologie di comunicazione già presenti, avendo così la possibilità di creare applicazioni di localizzazione che non necessitano di infrastrutture ad-hoc. Il personal radar scansiona automaticamente l'ambiente circostante e mediante l'utilizzo di antenne colleziona le risposte provenienti dall'ambiente ad ogni direzione di scansione. Successivamente analizzando i dati collezionati il personal radar è in grado di dedurre la mappa dell'ambiente. Al momento le tecnologie più usate sono quella lidar o quella camera-based ma sono solitamente tecnologie più costose e che richiedono supporti meccanici e perfette condizioni di visibilità dell'ambiente. Per queste ragioni è interessante esplorare la tecnologia radar ad onde millimetriche. Questa teconologia infatti offre la possiilità di impacchettare un numero elevato di antenne in un piccolo spazio e quindi di realizzare diagrammi di radiazione molto stretti alle spese di una degradazione delle perfomance. Per queste ragioni è stato deciso di suddividere la tesi nei seguenti capitoli. Nel primo capitolo viene fornita una breve spiegazione della teoria radar con attenzione particolare alla tecnologia (FMCW) del dispositivo utilizzato. Nel secondo capitolo viene fornita una analisi della teoria dello SLAM con un approfondimento sulla teoria SLAM basata su grafi. Dopodichè è presente una analisi del dispositivo utilizzato. Nel quarto capitolo vengono descritti gli algoritmi sviluppati e i motivi per cui sono stati necessari e infine nel capitolo finale vengono riportati i risultati finali con le relative considerazioni