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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.
21

Clustering Approaches for Multi-source Entity Resolution

Saeedi, Alieh 10 December 2021 (has links)
Entity Resolution (ER) or deduplication aims at identifying entities, such as specific customer or product descriptions, in one or several data sources that refer to the same real-world entity. ER is of key importance for improving data quality and has a crucial role in data integration and querying. The previous generation of ER approaches focus on integrating records from two relational databases or performing deduplication within a single database. Nevertheless, in the era of Big Data the number of available data sources is increasing rapidly. Therefore, large-scale data mining or querying systems need to integrate data obtained from numerous sources. For example, in online digital libraries or E-Shops, publications or products are incorporated from a large number of archives or suppliers across the world or within a specified region or country to provide a unified view for the user. This process requires data consolidation from numerous heterogeneous data sources, which are mostly evolving. By raising the number of sources, data heterogeneity and velocity as well as the variance in data quality is increased. Therefore, multi-source ER, i.e. finding matching entities in an arbitrary number of sources, is a challenging task. Previous efforts for matching and clustering entities between multiple sources (> 2) mostly treated all sources as a single source. This approach excludes utilizing metadata or provenance information for enhancing the integration quality and leads up to poor results due to ignorance of the discrepancy between quality of sources. The conventional ER pipeline consists of blocking, pair-wise matching of entities, and classification. In order to meet the new needs and requirements, holistic clustering approaches that are capable of scaling to many data sources are needed. The holistic clustering-based ER should further overcome the restriction of pairwise linking of entities by making the process capable of grouping entities from multiple sources into clusters. The clustering step aims at removing false links while adding missing true links across sources. Additionally, incremental clustering and repairing approaches need to be developed to cope with the ever-increasing number of sources and new incoming entities. To this end, we developed novel clustering and repairing schemes for multi-source entity resolution. The approaches are capable of grouping entities from multiple clean (duplicate-free) sources, as well as handling data from an arbitrary combination of clean and dirty sources. The multi-source clustering schemes exclusively developed for multi-source ER can obtain superior results compared to general purpose clustering algorithms. Additionally, we developed incremental clustering and repairing methods in order to handle the evolving sources. The proposed incremental approaches are capable of incorporating new sources as well as new entities from existing sources. The more sophisticated approach is able to repair previously determined clusters, and consequently yields improved quality and a reduced dependency on the insert order of the new entities. To ensure scalability, the parallel variation of all approaches are implemented on top of the Apache Flink framework which is a distributed processing engine. The proposed methods have been integrated in a new end-to-end ER tool named FAMER (FAst Multi-source Entity Resolution system). The FAMER framework is comprised of Linking and Clustering components encompassing both batch and incremental ER functionalities. The output of Linking part is recorded as a similarity graph where each vertex represents an entity and each edge maintains the similarity relationship between two entities. Such a similarity graph is the input of the Clustering component. The comprehensive comparative evaluations overall show that the proposed clustering and repairing approaches for both batch and incremental ER achieve high quality while maintaining the scalability.
22

Les majeurs protégés en France : dénombrement, caractéristiques et dynamique d’une sous-population méconnue / Adult wards in France : enumeration, characteristics and dynamics of a little-known sub-population

Malherbe, Paskall Alice Cathy Marie 18 June 2012 (has links)
Depuis l’entrée en vigueur de la loi n° 68-5 du 3 janvier 1968 portant réforme du droit des incapables,la sous-population des majeurs protégés s’est fortement modifiée, aussi bien au niveau de son effectifqu’au niveau de sa structure. Toutefois, par manque de données statistiques, cette sous-population estde nos jours encore méconnue. Afin d’améliorer la connaissance de la sous-population des majeursprotégés nous avons réalisé une analyse démographique de sa dynamique. L’objectif était de comblerun certain nombre de lacunes concernant d’une part le stock de majeurs sous tutelle, curatelle ousauvegarde de justice (effectif, répartition par sexe et par âge...) et d’autre part les caractéristiques desouvertures, des fins et des changements de régime de protection (fréquence, décomposition desflux...). Ce travail de recherche mené grâce à une approche multi-sources, a permis de distinguer cequi dans les évolutions observées, tenait à la modification des comportements de mise sous protectionet ce qui tenait aux changements de composition de la population française du point de vue de l’âge etde l’état de santé. Il a conduit à mettre en évidence la liaison forte, mais en transformation, entre typede mesure de protection et caractéristiques des majeurs bénéficiaires. Enfin, ce travail de recherchepourra servir de base pour appréhender ultérieurement le devenir de la sous-population des majeursprotégés dans un contexte de modification législative. / The sub-population of wards in France has changed significantly, both in size and composition, sinceLaw no. 68-5 of 3 January 1968 on incapacitated adults came into force. However, a lack a statisticaldata means it is still badly known. To improve our knowledge of the sub-population of wards, ademographic analysis of its dynamics was conducted. The purpose was to fill knowledge gaps relatingto the existing population of vulnerable adults under guardianship (e.g. number, sex, age) and to thecharacteristics of the court orders establishing, amending or ending guardianship (e.g. frequency,flows). Thanks to a multi-source approach the study identifies what derives from the changes inbehaviour relating to the establishment of guardianship and from the changes undergone by the Frenchpopulation in terms of age structure and health. The study highlights a strong but changing relationshipbetween the type of guardianship and the characteristics of individual wards. The study may also serveas a starting point for further analysis of the sub-population of wards following recent changes in thelaw.
23

Účetní a daňové aspekty vícezdrojového financování obecně prospěšné společnosti / The multi-source financing of the Public service company - accounting and tax aspects

Šanderová, Zdeňka January 2017 (has links)
The thesis deals with the accounting and tax specifics of multi-source financing of non-governmental organizations. The tax aspects of individual sources are ana-lysed from the point of view of corporate income tax and value added tax, both in terms of donor and recipient. Aspects of accountants are described with respect to valid Czech legislation adjusting this issue. The main aim of the thesis is to analyse the accounting and tax implications of multi-source financing of a selected non-governmental non-profit organization and to identify the critical sites resulting from the use of these resources. The conclusion of the thesis is focused on the evaluation of the current status of selected NGOs and supplemented with suggestions for improvement.
24

Komparácia sociálnych služieb v ČR a v krajinách EÚ v období 2000-2012 / The comparison of social services in the Czech Republic and EU states in the period 2000-2012

Szabóová, Andrea January 2012 (has links)
The social services system in the Czech Republic intended for people in unfavorable social situation requires increased attention to financial sustainability, quality and overall effectiveness of their providing. The main point of this work is to examine and analyze the development of an instrument of social policy -- social services in the Czech Republic and in selected EU countries in the period 2000 - 2012. It is possible to highlight the weaknesses of the Czech system of social services by following comparison of the basic pillars. Positive and innovative experience of some EU countries is one of the possible ways how to solve defects in the Czech Republic.
25

Analýza zdrojové soběstačnosti NNO v kultuře / Analysis of the resource self-sufficiency of NGOs in culture

Svobodová, Lucie January 2011 (has links)
The Master's Thesis focuses on resource self-sufficiency analysis of four chosen NGOs in culture. Those are theatres Činoherní klub, Semafor, Archa and Dejvické divadlo. All of the organizations underwent the Prague theatre transformation process and became the Public Service Companies. The Thesis investigates, whether the change into to private subject and the rising independence have led also to the increase of resource self-sufficiency and extension of financial resource portfolio. For this purpose the financial statements of the theatres were analysed. The resource self-sufficiency index was put in the context of other financial analysis indices. The Thesis has shown, that although the theatres use at least four financial resources, they are highly dependent on incomes from provided public services and especially on subsidies from the public budgets. The NGOs should improve their level of business activities and fundraising. The resource self-sufficiency of analysed theatres is between 35 and 52 %. While in three cases the self-sufficiency has been increasing, in the last case it has been decreasing continuously.
26

Optimisation et validation des méthodes de calcul de dose à distance des faisceaux d’irradiation pour leur application dans les études épidémiologiques et cliniques en radiothérapie / Optimization and validation of out-of-field dose calculation methods in external beam radiation therapy for use in epidemiological and clinical studies

Vũ Bezin, Jérémi 17 December 2015 (has links)
La proportion de survivants à un cancer dans la population des pays développés augmente rapidement. Dans plus de la moitié des cas, la radiothérapie a été une composante de leur traitement. Les rayons ionisants alors administrés peuvent induire de graves conséquences à long terme, en particulier les cancers radio-induits et les maladies cardiovasculaires. Ces évènements sont dus non seulement aux fortes doses administrées au volume cible, mais également aux doses plus faibles, de quelques milligray à quelques gray, non souhaitées, mais inévitablement administrées dans le reste du corps du patient par la dose hors champ. L’évolution des techniques de planification du traitement et de l’informatique en médecine permettent aujourd’hui d’obtenir, systématiquement, l’évaluation précise des doses les plus fortes administrées au patient. Les doses faibles à intermédiaires administrées en dehors du faisceau de traitement, ne sont pour leur part, ni habituellement prises en compte, ni correctement évaluées par les systèmes actuels de planification du traitement. L’objectif de ce travail était de proposer des méthodes pour estimer le rayonnement hors champ des faisceaux de photons des accélérateurs de radiothérapie externe. L’utilisation d’une bibliothèque graphique nous a permis de réaliser une représentation géométrique 3D partielle des appareils de traitement et des sources photoniques responsables de la dose reçue par le patient. Nous avons déterminé l’intensité de ces sources en utilisant des mesures réalisées dans des champs simples. Le modèle ainsi calibré permettait de simuler la variation de l’intensité des sources en fonction de la taille du champ. Cette approche a permis de décrire avec succès la variation de la dose mesurée par TLD en fonction de la distance et de la taille du champ en dehors de champs carrés. Les écarts entres les doses calculées et celles mesurées étaient inférieurs à 10 %. Une application dans des conditions cliniques a été menée, l’écart était alors en moyenne de 25 %. / The number of cancer survivors in developed counties increases rapidly. Fifty percent of patients treated for cancer will receive radiation therapy as part of their treatment. Ionizing radiation may induce severe long term effects, including secondary cancers and cardio-vascular diseases. Long term effects are not only due to high doses delivered in target volumes, but also to lower doses, ranging from several milligrays to several grays, undesired, but inevitably delivered in the rest of the patient’s body outside the treatment beams. Improvements in treatment planning technics and the use of computers in medicine made it possible to systematically estimate, prior to treatment, the highest doses delivered to the patient’s body. However, lower doses delivered outside the treatment beams are neither taken into account nor evaluated by present treatment planning systems. The aim of our work was to establish methods to estimate radiation doses outside photon beams from accelerators used in external radiation therapy. A graphics library was used to render a partial 3D representation of the accelerator and the photon sources associated. The intensity of these sources was determined using measurements performed in simple geometry fields. The calibrated model was hence used to estimate the source intensity variation with respect to field size. Using this method, we were able to estimate the variations of the TLD measured doses with respect to distance and field size with a 10% average discrepancy between calculations and measurements for points outside the field. Also, when testing the model in a clinical setup, the average discrepancy increased to 25%.
27

Přínos a význam vlastních finančních zdrojů ze sociálního podnikání pro nestátní neziskové organizace / Benefits and importance of financial resources of social entrepreneurship for nonprofit organizations

Fialová, Dagmar January 2012 (has links)
This diploma thesis is focused on the contribution and importance of financial resources of social entrepreneurship for nonprofit organizations. The main goal is to analyze the evolution of nonprofit organization's funding from Czech public funds and to identify benefits and importance of financial resources of social entrepreneurship for nonprofit organizations. The theoretical part brings description of financial resources for nonprofit organizations and explanation of social entrepreneurship concept and social enterprise definition. The research of diploma thesis brings the analysis of evolution of nonprofit organization's funding from Czech public funds from 1999 to 2009 and the identification of benefits, importance and share of financial resources of social entrepreneurship in specific nonprofit organization - Domov Sue Ryder, o.p.s. The identification of benefits and importance of financial resources of social entrepreneurship is based on the analysis of evolution of sources, costs and own revenues (sources) from 2001 to 2010 in selected nonprofit organization. The output of this diploma thesis is the evaluation of benefits and importance of financial resources of social entrepreneurship for nonprofit organizations.
28

Multi-source Energy Harvesting for Wildlife Tracking

Wu, You 06 July 2015 (has links)
Sufficient power supply to run GPS machinery and transmit data on a long-term basis remains to be the key challenge for wildlife tracking technology. Traditional ways of replacing battery periodically is not only time and money consuming but also dangerous to live-trapping wild animals. In this paper, an innovative wildlife tracking collar with multi-source energy harvester with advantage of high efficiency and reliability is proposed. This multi-source energy harvester entails a solar energy harvester and an innovative rotational electromagnetic energy harvester is mounted on the "wildlife tracking collar" which will extend the duration of wild life tracking by 20% time as was estimated. A feedforward and feedback control of DC-DC converter circuit is adopted to passively realize the Maximum Power Point Tracking (MPPT) logic for the solar energy harvester. A novel electromagnetic pendulum energy harvester with motion regulator is proposed which can mechanically rectify the irregular bidirectional swing motion of the pendulum into unidirectional rotational motion of the motor. No electrical rectifier is needed and voltage drops from diodes can be avoided, the EM pendulum energy harvester can provide 200~300 mW under the 0.4g base excitation of 4.5 Hz. The nonlinearity of the disengage mechanism in the pendulum energy harvester will lead to a broad bandwidth frequency response. Simulation results shows the broadband advantage of the proposed energy harvester and experiment results verified that at some frequencies over the natural frequency the efficiency is increased. / Master of Science
29

Caractérisation Multi-physique des éléments de stockage électrochimique et électrostatique dédiés aux systèmes Multi sources : Approche systémique pour la gestion dynamique d'énergie électrique / Multi-physical characterization of electrochemical and electrostatic storage elements dedicated to multi-source systems : Systemic approach for the dynamic management of electrical energy

Bellache, Kosseila 10 July 2018 (has links)
Ce travail de thèse s’inscrit dans la continuité des activités de recherche du laboratoire GREAH sur les problématiques de la gestion d’énergie électrique et de l’amélioration de la qualité énergétique des systèmes de production aux énergies renouvelables. En effet, le couplage de plusieurs sources de natures différentes entraîne des problématiques de dimensionnement, de qualité d’énergie et de la durée de vie des éléments interconnectés. La démarche scientifique repose sur la caractérisation de l'évolution des résistances et des capacités des cellules de batteries LFP/supercondensateurs en fonction des contraintes électriques et thermiques, suivi de la modélisation du vieillissement accéléré des cellules. Nous proposons dans ce mémoire de thèse des améliorations de la réponse dynamique d’un bateau fluvial à propulsion électrique par l’hybridation des batteries LFP et des supercondensateurs. Nous proposons également une approche électrothermique pour la caractérisation et la modélisation multi-physique du vieillissement des batteries et supercondensateurs en utilisant des contraintes combinées de la température et de la fréquence des ondulations du courant de charge/décharge des cellules. Les données expérimentales collectées ont permis d'établir des modèles des supercondensateurs et des batteries dédiés aux systèmes multi-sources incluant des sources d’énergie renouvelable (éoliens et hydroliens). Les modèles développés se révèlent très précis par rapport aux résultats expérimentaux. Ils permettent une bonne description du phénomène de vieillissement des batteries LFP/supercondensateurs dû aux opérations de charge/décharge avec un courant continu fluctuant combiné à une température variable. / This thesis work is a continuation of the research activities of the GREAH laboratory on the issues of the management of electrical energy and improving the energy quality of production systems for renewable energy. Indeed, the coupling of several different nature sources entails the problems of dimension, quality of energy and the lifetime of the interconnected elements. The scientific approach is based on the characterization of the evolution of the resistances and capacitances of the batteries/supercapacitors cells according to the electrical and thermal constraints, followed by the modeling of accelerated cells aging. In this thesis, we propose improvements to the dynamic response of an electric propulsion fluvial boat by using the hybrid system of lithium-batteries and supercapacitors. We also propose an electrothermal approach for the multi-physical characterization and modeling of the batteries and supercapacitors aging, using combined constraints of the temperature and frequency of the DC current ripples. The experimental data has been collected to establish models of batteries and supercapacitors dedicated to multi-source systems including renewable energy sources (wind and tidal turbines). The results of the developed models shown high accuracy compared with experimental results. These models illustrated a good description of the aging phenomenon of batteries/ supercapacitors due to charging/discharging operations with a fluctuating continuous current combined with a variable temperature.
30

Cooperative wireless communications in the presence of limited feedback / Communications sans fil coopératives en présence de voies de retour à débit limité

Cerovic, Stefan 25 September 2019 (has links)
Dans cette thèse, les techniques de coopération ont été étudiées pour un canal multi-accès multi-relais composé d'au moins deux sources qui communiquent avec une seule destination à l'aide d'au moins deux nœuds de relayage en mode semi-duplex. Le multiplexage par répartition dans le temps est supposé. Tout d'abord, l’algorithme d’adaptation de lien est exécuté par l'ordonnanceur centralisé. Durant la première phase de transmission, les sources transmettent chacune à leur tour leur message respectif pendant des intervalles de temps consécutifs. Dans chaque intervalle de temps dans la deuxième phase, la destination planifie un nœud pour transmettre les redondances, mettant en œuvre un protocole coopératif d'Hybrid Automatic Repeat reQuest (HARQ), où les canaux de contrôle limités bidirectionnels sont disponibles depuis les sources et les relais vers la destination. Dans la première partie de la thèse, les stratégies de sélection des nœuds centralisé sont proposées pour la deuxième phase de transmission. Les décisions d’ordonnancement sont prises en fonction de la connaissance des ensembles de sources correctement décodées par chaque noeud et ayant comme objectif de maximiser l’efficacité spectrale moyenne. L'analyse de la probabilité de coupure de l'information ainsi que les simulations Monte-Carlo (MC) sont effectués afin de valider ces stratégies. Dans la seconde partie, un algorithme d’adaptation de lien lent est proposé afin de maximiser l’efficacité spectrale moyenne sous contrainte de vérification d'une qualité de service individuelle cible pour une famille donnée de schémas de modulation et de codage, réposant sur l'information sur la distribution des canaux signalée. Les débits des sources discrets sont déterminés en utilisant l’approche "Genie-Aided" suivie d’un algorithme itératif de correction de débit. Les simulations MC montrent que l’algorithme d’adaptation de lien proposé offre des performances proches de celles de la recherche exhaustive. Dans la troisième partie, les performances de protocole HARQ à redondance incrémentale (IR) avec codage mono et multi-utilisateur, ainsi que l'HARQ de type Chase Combining avec codage mono-utilisateur sont comparées. Les simulations MC montrent que l'IR-HARQ avec codage mono-utilisateur offre le meilleur compromis entre performance et complexité pour le scénario de petit nombre de sources. Un schéma de codage pratique est proposé et validé à l'aide de simulations MC. / In this thesis, cooperation techniques have been studied for Multiple Access Multiple Relay Channel, consisted of at least two sources which communicate with a single destination with the help of at least two half-duplex relaying nodes. Time Division Multiplexing is assumed. First, the link adaptation algorithm is performed at the centralised scheduler. Sources transmit in turns in consecutive time slots during the first transmission phase. In each time slot of the second phase, the destination schedules a node to transmit redundancies, implementing a cooperative Hybrid Automatic Repeat reQuest (HARQ) protocol, where bidirectional limited control channels are available from sources and relays towards the destination. In the first part of the thesis, centralized node selection strategies are proposed for the second phase. The scheduling decisions are made based on the knowledge of the correctly decoded source sets of each node, with the goal to maximize the average spectral efficiency. An information outage analysis is conducted and Monte-Carlo (MC) simulations are performed to evaluate their performance. In the second part, a slow-link adaptation algorithm is proposed which aims at maximizing the average spectral efficiency under individual QoS targets for a given modulation and coding scheme family relying on the reported Channel Distribution Information of all channels. Discrete source rates are first determined using the "Genie-Aided" assumption, which is followed by an iterative rate correction algorithm. The resulting link adaptation algorithm yields performance close to the exhaustive search approach as demonstrated by MC simulations. In the third part, performances of Incremental Redundancy (IR) HARQ with Single and Multi User encoding, as well as the Chase Combining HARQ with Single User encoding are compared. MC simulations demonstrate that IR-HARQ with Single User encoding offers the best trade-off between performance and complexity for a small number of sources in our setting. Practical coding scheme is proposed and validated using MC simulations.

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