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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Self-optimization of Antenna Sectorization

Faxér, Sebastian January 2014 (has links)
Sectorization is a well-established method of increasing the capacity of telecommunicationnetworks. With modern Active Antenna Systems (AAS) comes the abilityto change sectorization order dynamically, both in horizontal and vertical plane.The purpose of this thesis is to investigate when (and what type of) sectorizationis benficial. A theoretical analysis as well as simulations are performed in orderto determine which quantities to look at when making the decision to apply sectorization.Based on the conclusions from these investigations, a self-optimizingalgorithm that only turns on sectorization when it increases network performanceis developed and evaluated. It is shown that large gains can be achieved by onlyturning on sectorization when the right conditions are met. Further, we show thatadditional gains can be seen if antenna parameters such as downtilt and distributionof transmission power between sectors are set properly. Self-optimizingalgorithms for tuning of these parameters are developed and evaluated as well.NyckelordKeywords
2

Le problème de la sectorisation multicritère en cartographie / Multicriteria sectorization problems in cartography

Tang, Xin 28 November 2012 (has links)
Les travaux présentés dans cette thèse visent à proposer des méthodes pour résoudre les problèmes de la sectorisation multicritère en cartographie. En premier temps, nous avons défini les problèmes différents de la sectorisation et nous avons établi les liens entre ces problèmes avec les problèmes classiques qui sont bien étudiés dans la littérature : le problème de découpage de district politique, les problèmes de localisation et le problème du partitionnement de graphe. Deux types de méthodes ont été abordés pour résoudre les problèmes de sectorisation. Des heuristiques ont été développées et elles consistent à calculer un optimum de Pareto pour les différents problèmes. Et pour le problème de sectorisation à partir de pôles, nous avons aussi utilisé et expérimenté un algorithme de boîte pour trouver une représentation du front de pareto. La méthode exacte branch and bound a été utilisée pour résoudre le problème de sectorisation sans pôle prédéfini optimalement. Avant que nous appliquons cette procédure, nous ajoutons quelques inégalités valides dans la formulation mathématique pour restreindre l'espace des solutions et nous développons une procédure de prétraitement pour réduire la taille du problème. / The work presented in this thesis aims to propose methods to solve the multicriteria map sectorization problem in cartography. Firstlly, we have defined the different sectorization problems and we have established the links between these problems with some classical problems which are well studied in the literature : political districting problem, locationallocation problems and constrained graph partitioning problems. Two types of methods have been proposed to solve the sectorization problem. Heuristics have been developed and they compute an optimum Pareto for the different sectorization problems. And for the sectorization problem with predefined centers, we have used a box algorithm and experimented it to find a representation of the Pareto front. The branch and bound method was used to solve optimally the sectorization problem without predefined centers. Before we apply this procedure, we add some valid inequalities in the mathematical formulation for restrict the space of solutions and we develop a preprocessing procedure to reduce the size of the problem.
3

Modelo computacional de otimização para dimensionamento de redes de distribuição de água abastecidas por múltiplos bombeamentos. / Computational model of optimization for sizing of water distribution networks supplied by multiple pumping.

Gouveia, Roberta Macêdo Marques 20 September 2012 (has links)
Made available in DSpace on 2015-05-08T14:59:45Z (GMT). No. of bitstreams: 1 Arquivototal.pdf: 7182461 bytes, checksum: a98f0cc042311821ced96a1784670e80 (MD5) Previous issue date: 2012-09-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The high costs involved in water distribution systems, particularly with regard to the design and operation thereof, reflect the importance of studying ways to minimize the loss of water and electricity, in order to increase the efficiency of these systems. In an attempt to minimize and avoid such loss, This study commit to investigate and propose a model optimized sizing of networks, with emphasis on hydraulic efficiency, energy and economic. The main objective is to minimize system costs, understood by the network pipe costs, the energy of pumping main (main system of impulsion) and the energy of pumping secondary, represented by boosters. The proposed methodology for the sizing considers the energy costs of multiple pumping, plus the cost of implantation of the pipes. Using this methodology it is possible to achieve a design with lower pressures and longer appropriate, with consequent reduction in energy and water losses throughout the system. To achieve the proposed objectives, the methodology used in this study comprehend an iterative algorithm and dynamic of optimization. The said algorithm originated the program Toolkit of Sizing Optimized (TDO), that have been implemented using the EPANET Programmer's Toolkit. To validate the theory, case studies were conducted with three water distribution networks: network Grande Setor Expanded , network R9 Adapted and network Hanoi The results obtained, using the TDO, demonstrate that the sizing most suitable for operation of the networks studied were obtained using sectorization, through the inclusion of secondary pumping. / Os altos custos envolvidos nos sistemas de distribuição de água, particularmente no que diz respeito aos projetos e operação dos mesmos, refletem a importância de se estudar meios de minimizar os desperdícios de água e energia elétrica, a fim de elevar a eficiência desses sistemas. Na tentativa de minimizar e evitar tais desperdícios, este trabalho empenha-se em investigar e propor um modelo de dimensionamento otimizado de redes, com ênfase na eficiência hidráulica, energética e econômica. O principal objetivo é minimizar os custos do sistema, compreendido pelos custos das tubulações da rede, da energia do bombeamento principal (sistema principal de impulsão) e da energia dos bombeamentos secundários, representados por boosters. A metodologia proposta para o dimensionamento considera os custos energéticos dos múltiplos bombeamentos, além do custo de implantação das tubulações. Com o emprego desta metodologia pode-se alcançar um dimensionamento com pressões menores e mais adequadas, com a consequente diminuição das perdas de água e energia em todo o sistema. A fim de alcançar os objetivos propostos, a metodologia empregada neste trabalho compreende um algoritmo iterativo e dinâmico de otimização. O referido algoritmo deu origem ao programa Toolkit de Dimensionamento Otimizado (TDO), tendo sido implementado utilizando o toolkit de programação do simulador hidráulico EPANET 2.0. Para validar o trabalho, realizaram-se alguns estudos de casos com três redes de distribuição de água: rede Grande Setor Expandida, rede R9 Adaptada e rede Hanoi. Os resultados alcançados, pelo TDO, demonstram que os dimensionamentos mais adequados para operação das redes estudadas foram obtidos com a setorização, por meio da inclusão dos bombeamentos secundários.
4

Shaping the Next Generation Air Transportation System with an Airspace Planning and Collaborative Decision Making Model

Hill, Justin Mitchell 30 September 2009 (has links)
This dissertation contributes to the ongoing national project concerning the \emph{Next Generation Air Transportation System} (NextGen) that endeavors, in particular, to reshape the management of air traffic in the continental United States. Our work is part of this effort and mainly concerns modeling and algorithmic enhancements to the Airspace Planning and Collaborative Decision-Making Model (APCDM). First, we augment the APCDM to study an \emph{Airspace Flow Program} (AFP) in the context of weather-related disruptions. The proposed model selects among alternative flight plans for the affected flights while simultaneously (a) integrating slot-exchange mechanisms induced by multiple Ground Delay Programs (GDPs) to permit airlines to improve flight efficiencies through a mediated bartering of assigned slots, and (b) considering issues related to sector workloads, airspace conflicts, as well as overall equity concerns among the involved airlines in regard to accepted slot trades and flight plans. More specifically, the APCDM is enhanced to include the following: a. The revised model accommodates continuing flights, where some flight cannot depart until a prerequisite flight has arrived. Such a situation arises, for example, when the same aircraft will be used for the departing flight. b. We model a slot-exchange mechanism to accommodate flights being involved in multiple trade offers, and to permit slot trades at multiple GDP airports (whence the flight connection constraints become especially relevant). We also model flight cancelations whereby, if a flight assigned to a particular slot is canceled, the corresponding vacated slot would be made available for use in the slot-exchange process. c. Alternative equity concepts are presented, which more accurately reflect the measures used by the airlines. d. A reduced variant of the APCDM, referred to as \textbf{APCDM-Light}, is also developed. This model serves as a fast-running version of APCDM to be used for quick-turn analyses, where the level of modeling detail, as well as data requirements, are reduced to focus only on certain key elements of the problem. e. As an alternative for handling large-scale instances of APCDM more effectively, we present a \emph{sequential variable fixing heuristic} (SFH). The list of flights is first partitioned into suitable subsets. For the first subset, the corresponding decision variables are constrained to be binary-valued (which is the default for these decision variables), while the other variables are allowed to vary continuously between 0 and 1. If the resulting solution to this relaxed model is integral, the algorithm terminates. Otherwise, the binary variables are fixed to their currently prescribed values and another subset of variables is designated to be binary constrained. The process repeats until an integer solution is found or the heuristic encounters infeasibility. f. We experiment with using the APCDM model in a \emph{dynamic, rolling-horizon framework}, where we apply the model on some periodic basis (e.g., hourly), and where each sequential run of the model has certain flight plan selections that are fixed (such as flights that are already airborne), while we consider the selection among alternative flight plans for other imminent flights in a look-ahead horizon (e.g., two hours). These enhancements allow us to significantly expand the functionality of the original APCDM model. We test the revised model and its variants using realistic data derived from the \emph{Enhanced Traffic Management System} (ETMS) provided by the \emph{Federal Aviation Administration} (FAA). One of the new equity methods, which is based on average delay per passenger (or weighted average delay per flight), turns out to be a particularly robust way to model equity considerations in conjunction with sector workloads, conflict resolution, and slot-exchanges. With this equity method, we were able to solve large problem instances (1,000 flights) within 30 seconds on average using a 1\% optimality tolerance. The model also produced comparable solutions within about 20 seconds on average using the Sequential Fixing Heuristic (SFH). The actual solutions obtained for these largest problem instances were well within 1\% of the best known solution. Furthermore, our computations revealed that APCDM-Light can be readily optimized to a 0.01\% tolerance within about 5 seconds on average for the 1,000 flight problems. Thus, the augmented APCDM model offers a viable tool that can be used for tactical air traffic management purposes as an airspace flow program (particularly, APCDM-Light), as well as for strategic applications to study the impact of different types of trade restrictions, collaboration policies, equity concepts, and airspace sectorizations. The modeling of slot ownership in the APCDM motivates another problem: that of generating detoured flight plans that must arrive at a particular slot time under severe convective weather conditions. This leads to a particular class of network flow problems that seeks a shortest path, if it exists, between a source node and a destination node in a connected digraph $G(N,A)$, such that we arrive at the destination at a specified time while leaving the source no earlier than a lower bounding time, and where the availability of each network link is time-dependent in the sense that it can be traversed only during specified intervals of time. We refer to this problem as the \emph{reverse time-restricted shortest path problem} (RTSP). We show that RTSP is NP-hard in general and propose a dynamic programming algorithm for finding an optimal solution in pseudo-polynomial time. Moreover, under a special regularity condition, we prove that the problem is polynomially solvable with a complexity of order $O(|N / A|)$. Computational results using real flight generation test cases as well as random simulated problems are presented to demonstrate the efficiency of the proposed solution procedures. The current airspace configuration consists of sectors that have evolved over time based on historical traffic flow patterns. \citet{kopardekar_dyn_resect_2007} note that, given the current airspace configuration, some air traffic controller resources are likely under-utilized, and they also point out that the current configuration limits flexibility. Moreover, under the free-flight concept, which advocates a relaxation of waypoint traversals in favor of wind-optimized trajectories, the current airspace configuration will not likely be compatible with future air traffic flow patterns. Accordingly, one of the goals for the \emph{NextGen Air Transportation System} includes redesigning the airspace to increase its capacity and flexibility. With this motivation, we present several methods for defining sectors within the \emph{National Airspace System} (NAS) based on a measure of sector workload. Specifically, given a convex polygon in two-dimensions and a set of weighted grid points within the region encompassed by the polygon, we present several mixed-integer-programming-based algorithms to generate a plane (or line) bisecting the region such that the total weight distribution on either side of the plane is relatively balanced. This process generates two new polygons, which are in turn bisected until some target number of regions is reached. The motivation for these algorithms is to dynamically reconfigure airspace sectors to balance predicted air-traffic controller workload. We frame the problem in the context of airspace design, and then present and compare four algorithmic variants for solving these problems. We also discuss how to accommodate monitoring, conflict resolution, and inter-sector coordination workloads to appropriately define grid point weights and to conduct the partitioning process in this context. The proposed methodology is illustrated using a basic example to assess the overall effect of each algorithm and to provide insights into their relative computational efficiency and the quality of solutions produced. A particular competitive algorithmic variant is then used to configure a region of airspace over the U.S. using realistic flight data. The development of the APCDM is part of an ongoing \emph{NextGen} research project, which envisages the sequential use of a variety of models pertaining to three tiers. The \emph{Tier 1} models are conceived to be more strategic in scope and attempt to identify potential problematic areas, e.g., areas of congestion resulting from a severe convective weather system over a given time-frame, and provide aggregate measures of sector workloads and delays. The affected flow constrained areas (FCAs) highlighted by the results from these \emph{Tier 1} models would then be analyzed by more detailed \emph{Tier 2} models, such as APCDM, which consider more specific alternative flight plan trajectories through the different sectors along with related sector workload, aircraft conflict, and airline equity issues. Finally, \emph{Tier 3} models are being developed to dynamically examine smaller-scaled, localized fast-response readjustments in air traffic flows within the time-frame of about an hour prior to departure (e.g., to take advantage of a break in the convective weather system). The APCDM is flexible, and perhaps unique, in that it can be used effectively in all three tiers. Moreover, as a strategic tool, analysts could use the APCDM to evaluate the suitability of potential airspace sectorization strategies, for example, as well as identify potential capacity shortfalls under any given sector configuration. / Ph. D.
5

La capacidad hidráulica en las redes de agua potable y su influencia en el proceso de sectorización

Martins Alves, Carlos 21 January 2021 (has links)
[ES] La sectorización en sectores hidrométricos de las redes de abastecimiento de agua potable ha sido, a lo largo de los últimos años, una de las técnicas más empleadas para ubicar y controlar las fugas. Esto es de vital importancia ante un recurso, el agua potable, cada vez más escaso y valioso. Sin embargo, el empleo de esta técnica, algunas veces, es llevada a cabo por ensayo y error, o sin una estrategia previamente establecida. La capacidad hidráulica de la red, o caudal máximo que puede aportar cumpliendo los requisitos mínimos de servicio, puede afectarse cuando se lleva a cabo un proceso de sectorización. Esto es debido a que el cierre de tramos de la red cambia las condiciones de servicio, pudiendo generar afectaciones graves desde el punto de vista de presiones y de calidad de agua. Algunas veces, también, es aplicado el proceso de sectorización sin una evaluación previa de las características de la red y de las condiciones operativas. Partiendo de estas situaciones, se planteó indagar acerca de cómo las condiciones iniciales de operación de la red pudiesen afectar la formación de los sectores hidrométricos desde el punto de vista de su configuración. En los procesos de sectorización pueden emplearse algoritmos de clústering debido a la analogía existente entre los agrupamientos de los diferentes elementos de los sistemas de abastecimiento de agua y los principios aplicados en las técnicas de agrupamiento de datos. Así, se decidió aplicar diversas técnicas basadas en la detección de comunidades en redes, ya que poseen la ventaja de agrupar en función de la información en las conexiones, y no solo en la información almacenada en los nodos, lo cual resulta favorable para el tema en estudio en este trabajo, debido a que pudiera tomarse en cuenta cómo la variación de los niveles de exigencia en las tuberías, ocasionados por la variación en la demanda, afectaría la formación de sectores. Para ello se planteó trabajar con dos redes de prueba conocidas en la literatura, a las cuales se les simuló bajo distintas capacidades de carga de trabajo y a través del empleo de varios algoritmos de agrupamiento, tales como Infomap, Walktrap, Fast gready, Edge betweeness, Luovain y Leiden. La metodología desarrollada fue, finalmente, aplicada a una red real de gran tamaño, lo que valida dicha metodología para un problema del mundo real. Como parámetros para ponderar las conexiones se probaron cuatro opciones: caudal circulante con la red trabajando a la capacidad deseada; energía disipada en cada tramo con la red trabajando a la capacidad deseada; relación entre el caudal circulante en el tramo y el caudal circulante a capacidad máxima teórica de la red; y relación entre la energía disipada trabajando a la capacidad deseada y la disipación de la energía en los tramos con la red trabajando a capacidad máxima. Obtenida la partición por cualquiera de los métodos anteriormente expuestos, se optimizaron las entradas y salidas de los sectores por medio de la implementación de un algoritmo de enjambre de partículas; adicionalmente, se hace una comparación del resultado con otro obtenido a partir de un algoritmo de colonia de hormigas, lo que permite dar robustez a la metodología desarrollada. / [CA] La partició o sectorització de les xarxes d'abastiment d'aigua potable a les anomenades districtes hidromètrics ha estat, durant els darrers anys, una de les tècniques més utilitzades per localitzar i controlar les pèrdues d'aigua. La sectorització és crucial quan es tracta d'un recurs cada vegada més escàs i valuós com es l'aigua. Tanmateix, l'ús d'aquesta tècnica de vegades es duu a terme mitjançant proves i errors, o sense una estratègia prèviament establerta. La capacitat hidràulica d'una xarxa o el cabal màxim que pot proporcionar mentre compleix els requisits mínims de servei es pot veure afectat quan es realitza un procés de sectorització. Això es deu al fet que el tancament de seccions de la xarxa modifica les condicions del servei, la qual cosa pot generar greus efectes des del punt de vista de la pressió i la qualitat de l'aigua. A més, de vegades s'apliquen processos de sectorització sense una avaluació prèvia de les característiques de la xarxa i de les condicions de funcionament. Partint d'aquestes situacions, ens vam preguntar sobre com les condicions inicials de funcionament de la xarxa podrien afectar la construcció dels sectors hidromètrics des del punt de vista de la seva configuració. Els algoritmes de clusterització es poden utilitzar en processos de sectorització a causa de l'analogia entre l'agrupació dels diferents elements dels sistemes d'abastiment d'aigua i els principis aplicats en les tècniques d'agrupament de dades. Així, vam decidir aplicar diverses tècniques basades en la detecció de comunitats a les xarxes, ja que tenen l'avantatge de realitzar agrupacions basades en la informació de les unions i no només en la informació emmagatzemada als nodes. Això és favorable per al tema en estudi en aquest treball, perquè es pot considerar com la variació dels nivells de demanda a les canonades, causada per la variació de la demanda, pot afectar la construcció de sectors. Amb aquesta finalitat, es va proposar treballar amb dues xarxes de proves conegudes a la literatura, que es van simular sota diferents capacitats de càrrega i mitjançant l'ús de diversos algorismes de clusterització, com Infomap, Walktrap, Fast gready, Edge betweeness, Luovain i Leiden. La metodologia desenvolupada es va aplicar, finalment, a una gran xarxa real, que valida la metodologia per a una xarxa de subministrament d'aigua del món real. Com a paràmetres per ponderar les unions, es van provar quatre opcions: cabal circulant amb la xarxa treballant a la capacitat desitjada; energia dissipada a cada secció amb la xarxa treballant a la capacitat desitjada; relació entre el cabal circulant a la secció i el cabal circulant a la capacitat màxima teòrica de la xarxa; i la relació entre l'energia dissipada que treballa a la capacitat desitjada i la dissipació d'energia a les seccions amb la xarxa que treballa a la màxima capacitat. Un cop obtinguda la partició per qualsevol dels mètodes esmentats anteriorment, les entrades i sortides dels sectors s'optimitzen mitjançant un algorisme d'optimització d'eixam de partícules; a més, es fa una comparació del resultat amb un altre algoritme d'optimització, és a dir, un algoritme d'optimització de colònies de formigues, que permet proporcionar robustesa a la metodologia desenvolupada. / [EN] Partitioning or sectorization of drinking water supply networks into so-called district metered areas has been, over the last years, one of the most used techniques to locate and control leaks. Sectorization is crucial when dealing with an increasingly scarce and valuable resource as water. However, the use of this technique is sometimes carried out by trial and error, or without a previously established strategy. The hydraulic capacity of a network, or the maximum flow it can provide while meeting the minimum service requirements, can be affected when a sectorization process is carried out. This is due to the fact that the closure of sections of the network changes the service conditions, which could generate serious effects from the point of view of pressure and water quality. Also, sometimes sectorization processes are applied without a prior evaluation of the characteristics of the network and of the operating conditions. Starting from these situations, we inquired about how the initial operating conditions of the network could affect the construction of the hydrometric sectors or district metered areas from the point of view of their configuration. Clustering algorithms can be used in sectorization processes due to the analogy between the grouping of the different elements of water supply systems and the principles applied in data grouping techniques. Thus, we decided to apply various techniques based on the detection of communities in networks, since they have the advantage of performing grouping based on the information at the junctions, and not only on the information stored at the nodes. This is favourable for the subject under study in this work, because one may consider how the variation of the demand levels in the pipes, caused by the demand variation, can affect the construction of sectors. To this end, it was proposed to work with two test networks known in the literature, which were simulated under different load capacities and through the use of various clustering algorithms, namely Infomap, Walktrap, Fast gready, Edge betweeness, Luovain and Leiden. The methodology developed was, finally, applied to a large real network, which validates the methodology for a real-world water supply network. As parameters to weight the junctions, four options were tested: circulating flow with the network working at the desired capacity; energy dissipated in each section with the network working at the desired capacity; relationship between the circulating flow in the section and the circulating flow at the theoretical maximum capacity of the network; and the relationship between the energy dissipated working at the desired capacity and the dissipation of energy in the sections with the network working at maximum capacity. Once the partition is obtained by any of the previously said methods, the inputs and outputs of the sectors are optimized by using a particle swarm optimization algorithm; additionally, a comparison of the result is made with another optimization algorithm, namely, an ant colony optimization algorithm, which allows to provide robustness to the developed methodology. / Martins Alves, C. (2020). La capacidad hidráulica en las redes de agua potable y su influencia en el proceso de sectorización [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/159938 / TESIS
6

La sectorización basada en criterios energéticos como herramienta para la gestión hídrica de redes de distribución de agua

Salguero Barceló, Francisco Javier 13 December 2021 (has links)
[ES] La sectorización de las redes ha demostrado ser una metodología estratégica en la reducción de los volúmenes incontrolados fugados, considerado uno de los principales problemas a los que tienen que enfrentarse diariamente los gestores de los sistemas de distribución de agua. Su principal objetivo es facilitar la monitorización de las redes, dividiéndolas en subsistemas, sobre los que se puede realizar un mejor y más fácil control de las anomalías en el consumo y presión. Uno de los inconvenientes que presenta esta técnica recae en su diseño. No existe una solución única, sino que atiende a diversos criterios para realizarlo. De manera generalizada, este diseño se basa en la experiencia del propio diseñador, siguiendo criterios puramente prácticos y con procesos manuales de prueba y error, cuyo grado de dificultad está vinculado al tamaño y complejidad de la propia red. Esta tesis plantea una metodología sistemática para el diseño de la sectorización de una red de distribución de agua, según criterios energéticos, con el fin de facilitar la delimitación de cada uno de los sectores de la red. Como resultado, se obtiene una organización de la red en sectores buscando una optimización energética de la misma, de tal modo que posteriores técnicas de mejora, como es el caso de la gestión de presiones, se vean favorecidas. La sectorización ha resultado ser una técnica eficaz en la búsqueda de fugas. Sin embargo, como supone una pérdida de capacidad hidráulica y una merma en la calidad del agua, esta tesis se cuestiona el planteamiento de una técnica no intrusiva alternativa que logre los mismos resultados. Así, se propone el desarrollo de una metodología que localice las fugas centrada en la interdependencia de todos los elementos y en el empleo de sensores de caudal y presión. El trabajo pone de manifiesto que es posible sectorizar la red de tal manera que se consigan mayores beneficios para la misma. Ahora bien, también es posible el empleo de otras técnicas que no requieran el cierre de tuberías pero que desprendan soluciones similares. El empleo de una técnica u otra dependerá de cada caso, de los objetivos establecidos y de la política de trabajo de cada gestor. / [CA] La sectorització de les xarxes ha demostrat ser una metodologia estratègica en la reducció dels volums incontrolats perduts, considerat un dels principals problemes als quals han d'enfrontar-se diàriament els gestors dels sistemes de distribució d'aigua. El seu principal objectiu és facilitar la monitorització de les xarxes, dividint-les en subsistemes, sobre els quals es pot realitzar un millor i més fàcil control de les anomalies en el consum i pressió. Un dels inconvenients que presenta aquesta tècnica recau en el seu disseny. No existeix una solució única, sinó que atén diversos criteris per a realitzar-ho. De manera generalitzada, aquest disseny es basa en l'experiència del propi dissenyador, seguint criteris purament pràctics i amb processos manuals de prova i error, el grau de dificultat del qual està vinculat a la grandària i complexitat de la pròpia xarxa. Aquesta tesi planteja una metodologia sistemàtica per al disseny de la sectorització d'una xarxa de distribució d'aigua, segons criteris energètics, amb la finalitat de facilitar la delimitació de cadascun dels sectors de la xarxa. Com a resultat, s'obté una organització de la xarxa en sectors buscant una optimització energètica d'aquesta, de tal manera que posteriors tècniques de millora, com és el cas de la gestió de pressions, es vegen afavorides. La sectorització ha resultat ser una tècnica eficaç en la cerca de fuites d'aigua. No obstant això, com suposa una pèrdua de capacitat hidràulica i una disminució en la qualitat de l'aigua, aquesta tesi es qüestiona el plantejament d'una tècnica no intrusiva alternativa que aconseguisca els mateixos resultats. Així, es proposa el desenvolupament d'una metodologia que localitze les fuites d'aigua centrada en la interdependència de tots els elements i en l'ús de sensors de cabal i pressió. El treball posa de manifest que és possible sectoritzar la xarxa de tal manera que s'aconseguisquen majors beneficis per a aquesta. Ara bé, també és possible l'ús d'altres tècniques que no requerisquen el tancament de canonades però que desprenguen solucions similars. L'ús d'una tècnica o una altra dependrà de cada cas, dels objectius establits i de la política de treball de cada gestor. / [EN] The sectorization of networks has proven to be a strategic methodology in the reduction of uncontrolled leakage volumes, considered one of the main problems that water distribution system managers must face on a daily basis. Its main objective is to facilitate the monitoring of the networks, dividing them into subsystems, on which a better and easier control of anomalies in consumption and pressure can be performed. One of the drawbacks of this technique lies in its design. There is no single solution, but it is based on different criteria. In general, this design is based on the designer's own experience, following purely practical criteria and with manual trial and error processes, whose degree of difficulty is linked to the size and complexity of the network itself. This thesis proposes a systematic methodology for the design of the sectorization of a water distribution network, according to energy criteria, in order to facilitate the delimitation of each of the sectors of the network. As a result, an organization of the network in sectors is obtained, looking for an energetic optimization of the same, in such a way that later improvement techniques, such as pressure management, are favoured. Sectorization has proven to be an effective technique in the search for leaks. However, as it implies a loss of hydraulic capacity and a decrease in water quality, this thesis questions the approach of an alternative non-intrusive technique that achieves the same results. Thus, it is proposed the development of a methodology to locate the leaks focused on the interdependence of all the elements and the use of flow and pressure sensors. The present work shows that it is possible to sectorize the network in such a way as to achieve greater benefits for the network. However, it is also possible to use other techniques that do not require pipe closure but provide similar solutions. The use of one technique or another will depend on each case, on the established objectives and on the working policy of each manager. / Salguero Barceló, FJ. (2021). La sectorización basada en criterios energéticos como herramienta para la gestión hídrica de redes de distribución de agua [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/178235 / TESIS
7

Optimisation et Auto-Optimisation dans les réseaux LTE / Optimization and Self-Optimization in LTE-Advanced Networks

Tall, Abdoulaye 17 December 2015 (has links)
Le réseau mobile d’Orange France comprend plus de 100 000 antennes 2G, 3G et 4G sur plusieurs bandes de fréquences sans compter les nombreuses femto-cells fournies aux clients pour résoudre les problèmes de couverture. Ces chiffres ne feront que s’accroître pour répondre à la demande sans cesse croissante des clients pour les données mobiles. Cela illustre le défi énorme que rencontrent les opérateurs de téléphonie mobile en général à savoir gérer un réseau aussi complexe tout en limitant les coûts d’opération pour rester compétitifs. Cette thèse s’attache à utiliser le concept SON (réseaux auto-organisants) pour réduire cette complexité en automatisant les tâches répétitives ou complexes. Plus spécifiquement, nous proposons des algorithmes d’optimisation automatique pour des scénarios liés à la densification par les small cells ou les antennes actives. Nous abordons les problèmes classiques d’équilibrage de charge mais avec un lien backhaul à capacité limitée et de coordination d’interférence que ce soit dans le domaine temporel (notamment avec le eICIC) ou le domaine fréquentiel. Nous proposons aussi des algorithmes d’activation optimale de certaines fonctionnalités lorsque cette activation n’est pas toujours bénéfique. Pour la formulation mathématique et la résolution de tous ces algorithmes, nous nous appuyons sur les résultats de l’approximation stochastique et de l’optimisation convexe. Nous proposons aussi une méthodologie systématique pour la coordination de multiples fonctionnalités SON qui seraient exécutées en parallèle. Cette méthodologie est basée sur les jeux concaves et l’optimisation convexe avec comme contraintes des inégalités matricielles linéaires. / The mobile network of Orange in France comprises more than 100 000 2G, 3G and 4G antennas with severalfrequency bands, not to mention many femto-cells for deep-indoor coverage. These numbers will continue toincrease in order to address the customers’ exponentially increasing need for mobile data. This is an illustrationof the challenge faced by the mobile operators for operating such a complex network with low OperationalExpenditures (OPEX) in order to stay competitive. This thesis is about leveraging the Self-Organizing Network(SON) concept to reduce this complexity by automating repetitive or complex tasks. We specifically proposeautomatic optimization algorithms for scenarios related to network densification using either small cells orActive Antenna Systems (AASs) used for Vertical Sectorization (VeSn), Virtual Sectorization (ViSn) and multilevelbeamforming. Problems such as load balancing with limited-capacity backhaul and interference coordination eitherin time-domain (eICIC) or in frequency-domain are tackled. We also propose optimal activation algorithms forVeSn and ViSn when their activation is not always beneficial. We make use of results from stochastic approximationand convex optimization for the mathematical formulation of the problems and their solutions. We also proposea generic methodology for the coordination of multiple SON algorithms running in parallel using results fromconcave game theory and Linear Matrix Inequality (LMI)-constrained optimization.
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Socialpsykiatrins tillblivelse och fortlevnad : Att lära av historien kring vårdbemötande / Genesis and survival of social psychiatry : Learning from history about care meetings

Lundberg, Chris, Kataja, Fredrik January 2020 (has links)
Bakgrund. Innan dess att svensk psykiatri genomgick övergripande förändringar genomsyrades mentalhälsovården av olika psykologiska teorier vilka sedermera kom till att utgöra väsentliga beståndsdelar inom den “vårdkulturella revolutionens” fundament. Detta utmynnade därefter i svensk socialpsykiatris tillblivelse varigenom dessa försöksverksamheters väl fungerande praxis och kunskaper till synes har glömts bort genom åren. Metod. När, varför och hur har det gått från att vårdgivare/klient-relationen tidigare har betraktats vara “god” till att i dessa dagar te sig “avhumaniserad”? Hur var denna relation förr, hur är den i dag och hur kan den förslagsvis göras bättre framöver? För att kunna besvara detta tas en närmare blick, genom manifest kvalitativ innehållsanalys med konventionell (induktiv) ansats, på svensk hälso- och sjukvård emellan åren 1960–1980 såväl som en om än konkretiserad djupdykning ned i 1970-talets “nya psykiatri” och socialpsykiatriska försöksverksamheter. Resultat. Vägarna till utformandet av en vårdvärnande relation emellan vårdgivare och klient återfinns inom vårdgivarens bemötande och tillvägagångsätt gentemot klienten. Vad som fordras är en tillitsfull atmosfär och att bådadera parterna upprätthåller kontinuerlig kontakt (Gustafsson, 2010) vari tid bistår med goda förutsättningar i utformningen av funktionella tillika utvecklande allianser (Topor & Denhov, 2012). För att brukarinflytande skall fungera under förebyggande arbete, i led om att i största möjliga mån ta uti klienters problematik, krävs ett krispsykoterapeutiskt förhållningssätt och vetskap om psykisk kris genom vilka genuin närvaro uppnås (Cullberg, 1974). Forskning visar även tydligt att vad som behövs vid vårdbemötande är genuin närvaro, medmänsklig förståelse och rak kommunikation: att inte bara se människan, utan även att förstå vad just denna kris innebär för just denna individ såväl som att klientens beteende sett till sin helhet och vad som inte uttrycks säger så mycket mer än vad ord kan någonsin beskriva. Slutsats. Empirin antyder att aktuell forskning anmärker vad som fungerar bra och mindre bra, om inte alls, i relation till vårdbemötande är för all del bra. Men vad om nordisk socialpsykiatris pionjärer såsom Berggren, Cullberg och Haugsgjerd? Aktuell forskning refererar inte till någondera och deras arv tycks vara bortglömt. Så vad om all den kunskap och insikt som förvärvades och införlivades vid tidigare försöksverksamheter såsom Cullbergs kristeori och krispsykoterapi? Aktuell forskning refererar heller inte till någotdera och alltsammans tycks ha gått i stöpet. Vad som däremot framgår är att deras visioner tillämpades med mycket goda resultat vid bland annat Nackaprojektet tillika att sagda teori och psykoterapi tycks ha runnit ut i sanden efter verksamhetens nedläggning. Psykologin och psykiatrin, till syvende och sist, rör sig i ett gränsland emellan vetenskap och humaniora däri de, i samvaro med etisk kodex om att all behandling skall vila på “vetenskap och beprövad erfarenhet”, samexisterar i led om att med fumliga försök fånga livets komplexiteter. Men vart någonstans bör gränsdragningen gå emellan “vetenskaplig professionalitet” och “personlig inlevelse” när man möter någon med psykisk ohälsa, en medmänniska i psykisk kris? / Background. Prior to the undertaking of radical changes in Swedish psychiatry, various psychological theories permeated mental healthcare that would subsequently become essential components at the very heart of the “care-cultural revolution.” This subsequently resulted in the creation of Swedish social psychiatry through which trial establishments’ well-functioning praxis and knowledge have, so it seems, been forgotten over the years. Method. How, when and why has it gone from the fact that the caregiver/client-relationship has previously been considered as “good” to in these days feel as though it has become “dehumanized”? How was this relationship in the past, how is it as of today, and how can it be made better for the future? In order to answer this, a closer look, through manifest qualitative content analysis with conventional (inductive) approach, is taken on Swedish health care throughout the 1960s–1980s as well as an elaborate deep dive down into the “new psychiatry” of the 1970s and social psychiatric trial establishments. Result. The paths to the formation of a care-ensuring relationship between caregiver and client are found within caregivers’ attitude and approach towards their clients. What is required is a trusting atmosphere and that both parties maintain continuous contact (Gustafsson, 2010) wherein time provides good conditions in the formation of functional and developing alliances (Topor & Denhov, 2012). In order for user influence to function during preventive work, in line with addressing clients’ problems as much as possible, a crisis psychotherapeutic approach and knowledge of mental crisis is required through which genuine presence is achi-eved (Cullberg, 1974). Research also clearly shows that what is needed during care meetings is genuine presence, compassionate understanding, and straightforward communication: not only to see the person, but also to understand what this particular crisis means for this particular individual as well as that his or her behavior in itself and what is not being expressed says so much more than words can ever describe. Conclusion. Empirical data suggests that current research remarks on what works well and less well, if not at all, in relation to care treatment is certainly good. But what about the pioneers of Nordic social psychiatry like Berggren, Cullberg, and Haugsgjerd? Current research refers to neither and their legacies seem to have been forgotten. So, what about all the know-ledge and insight that was acquired and incorporated in previous experimental activities such as Cullberg's crisis theory and crisis psychotherapy? Current research refers, likewise, to neither and everything seems to have gone down the drain. What is clear, however, is that their visions were applied with very good results in, amongst other things, the Nacka Project as well as that said theory and psychotherapy seem to have faded away following the trial establishment’s closure. Psychology and psychiatry, ultimately, move in a borderland between science and the humanities wherein they, in conjunction with the code of ethics that all treatment is to be based on “science and proven experience,” coexist in line with fumble attempts to capture life’s complexities. But where exactly should the line be drawn between “scientific professionalism” and “personal insight” when meeting someone with mental ill-health, a fellow human being in a mental crisis?

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