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141	Reconhecimento de padrões em sistemas de energia elétrica através de uma abordagem geométrica aprimorada para a construção de redes neurais artificiais Valente, Wander Antunes Gaspar 09 February 2015 (has links) Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-01-08T10:36:58Z No. of bitstreams: 1 wanderantunesgasparvalente.pdf: 4197156 bytes, checksum: 5b667869c3bb237e570559ddf4cbb30d (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-01-25T16:56:26Z (GMT) No. of bitstreams: 1 wanderantunesgasparvalente.pdf: 4197156 bytes, checksum: 5b667869c3bb237e570559ddf4cbb30d (MD5) / Made available in DSpace on 2016-01-25T16:56:26Z (GMT). No. of bitstreams: 1 wanderantunesgasparvalente.pdf: 4197156 bytes, checksum: 5b667869c3bb237e570559ddf4cbb30d (MD5) Previous issue date: 2015-02-09 / O presente trabalho fundamenta-se no método das segmentações geométricas sucessivas (MSGS) para a construção de uma rede neural artificial capaz de gerar tanto a topologia da rede quanto o peso dos neurônios sem a especificação de parâmetros iniciais. O MSGS permite identificar um conjunto de hiperplanos no espaço Rn que, quando combinados adequadamente, podem separar duas ou mais classes de dados. Especificamente neste trabalho é empregado um aprimoramento ao MSGS com base em estimativas de densidade por kernel. Utilizando-se KDE, é possível encontrar novos hiperplanos de separação de forma mais consistente e, a partir daí, conduzir à classificação de dados com taxas de acerto superiores à técnica originalmente empregada. Neste trabalho, o MSGS aprimorado é empregado satisfatoriamente pela primeira vez para a identificação de padrões em sistemas de energia elétrica. O método foi ajustado para a classificação de faltas incipientes em transformadores de potência e os resultados apresentam índices de acerto superiores a trabalhos correlatos. O MSGS aprimorado também foi adaptado para classificar e localizar faltas inter-circuitos em linhas áreas de transmissão em circuito duplo, obtendo resultados positivos em comparação com a literatura científica. / This work is based on the method of successive geometric segmentations (SGSM) for the construction of an artificial neural network capable of generating both the network topology as the weight of neurons without specifying initial parameters. The MSGS allows to identify a set of hyperplanes in the Rn space that when properly combined, can separate two or more data classes. Specifically in this work is used an improvement to SGSM based on kernel density estimates (KDE). Using KDE, it is possible to find new hyperplanes of separation more consistently and, from there, lead to data classification with accuracy rates higher than originally technique. In this paper, the improved SGSM is first used satisfactorily to identify patterns in electrical power systems. The method has been adjusted to the classification of incipient faults in power transformers and the results have achieved rates above related work. The improved SGSM has also been adapted to classify and locate inter-circuit faults on double circuit overhead transmission lines with positive results compared with the scientific literature. CNPQ::ENGENHARIAS::ENGENHARIA ELETRICA Classificação de dados Estimativa de densidade por kernel Linhas de transmissão em circuito duplo Reconhecimento de padrões Redes neurais artificiais Transformadores de potência Artificial neural networks Data classification Double circuit transmission lines Kernel density estimation Pattern recognition Power transformers
142	Linearization Based Model Predictive Control of a Diesel Engine with Exhaust Gas Recirculation and Variable-Geometry Turbocharger Gustafsson, Jonatan January 2021 (has links) Engine control systems aim to ensure satisfactory output performance whilst adhering to requirements on emissions, drivability and fuel efficiency. Model predictive control (MPC) has shown promising results when applied to multivariable and nonlinear systems with operational constraints, such as diesel engines. This report studies the torque generation from a mean-value heavy duty diesel engine with exhaust gas recirculation and variable-geometry turbocharger using state feedback linearization based MPC (LMPC). This is accomplished by first introducing a fuel optimal reference generator that converts demands on torque and engine speed to references on states and control signals for the MPC controller to follow. Three different MPC controllers are considered: a single linearization point LMPC controller and two different successive LMPC (SLMPC) controllers, where the controllers are implemented using the optimization tool CasADi. The MPC controllers are evaluated with the World Harmonized Transient Cycle and the results show promising torque tracking using a SLMPC controller with linearization about reference values. MPC Model Predictive Control LMPC Linearization Based MPC SLMPC Successive Linearization Based MPC Reference Generator CasADi EGR Exhaust Gas Recirculation VGT Variable-Geometry Turbocharger Diesel Engine Heavy Duty Diesel Engine Automatic Control WHTC World Harmonized Transient Cycle Direct Multiple Shooting Control Engineering Reglerteknik
143	[en] INTERFERENCE MITIGATION SCHEMES FOR THE UPLINK OF MASSIVE MIMO IN 5G HETEROGENEOUS CELLULAR NETWORKS / [pt] MITIGAÇÃO DE INTERFERÊNCIAS EM SISTEMAS MIMO MASSIVO OPERANDO EM REDES HETEROGÊNEAS DE QUINTA GERAÇÃO (5G) JOSE LEONEL AREVALO GARCIA 15 August 2016 (has links) [pt] Na primeira parte desta tese, são desenvolvidos dois esquemas de detecção por listas para sistemas MIMO multiusuário. As técnicas propostas usam uma única transformação de redução de reticulado (LR) para modificar a matriz de canal entre os usuários e a estação base (BS). Após a transformação LR, um candidato confiável do sinal transmitido é obtido usando um detector de cancelamento sucessivo de interferências (SIC). No detector em múltiplos ramos com redução de reticulado e cancelamento sucessivo de interferências (MB-LR-SIC) proposto, um número fixo de diferentes ordenamentos para o detector SIC gera uma lista de possíveis candidatos para a informação transmitida. O melhor candidato é escolhido usando o critério maximum likelihood (ML). No detector por listas de tamanho variável (VLD) proposto, um algoritmo que decide se o candidato atual tem uma boa qualidade ou se é necessário continuar procurando por um candidato melhor nos ordenamentos restantes é utilizado. Os resultados numéricos mostram que os esquemas propostos têm um desempenho quase ótimo com uma complexidade computacional bem abaixo do detector ML. Um esquema de detecção e decodificação iterativa (IDD) baseado no algoritmo VLD é também desenvolvido, produzindo um desempenho próximo a um sistema mono usuário (SU) livre de interferências. Na segunda parte desta tese, uma técnica de detecção desacoplada de sinais (DSD) para sistemas MIMO massivo é proposta. Esta técnica permite que o sinal composto recebido na BS seja separado em sinais independentes, correspondentes a diferentes classes de usuários, viabilizando assim o uso dos procedimentos de detecção propostos na primeira parte desta tese em sistemas MIMO massivos. Um modelo de sinais para sistemas MIMO massivo com antenas centralizadas e/ou antenas distribuídas operando em redes heterogêneas de quinta geração é proposto. Uma análise baseada na soma das taxas e um estudo de custo computacional para DSD são apresentados. Os resultados numéricos ilustram o excelente compromisso desempenho versus complexidade obtido com a técnica DSD quando comparada com o esquema de detecção conjunta tradicional. / [en] In the first part of this thesis, we introduce two list detection schemes for the uplink scenario of multiuser multiple-input multiple-output (MUMIMO) systems. The proposed techniques employ a single lattice reduction (LR) transformation to modify the channel matrix between the users and the base station (BS). After the LR transformation, a reliable candidate for the transmitted signal vector, provided by successive interference cancellation (SIC) detection is obtained. In the proposed multi-branch lattice reduction SIC (MB-LR-SIC) detector, a fixed number of different orderings, generates a list of SIC detection candidates. The best candidate is chosen according to the maximum likelihood (ML) selection criterion. For the proposed variable list detection (VLD) scheme, an algorithm to decide if the current candidate has good quality or if it is necessary to further explore different orderings to improve the detection performance is employed. Simulation results indicate that the proposed schemes have a near-optimal performance while keeping its computational complexity well below that of the ML detector. An iterative detection and decoding (IDD) scheme based on the VLD algorithm is also developed, producing an excellent performance that approaches the single user (SU) scenario. In the second part of this thesis, a decoupled signal detection (DSD) technique which allows the separation of uplink signals, for each user class, at the base station (BS) for massive MIMO systems is proposed. The proposed DSD allows to implement the detection procedures proposed in the first part of this thesis in massive MIMO scenarios. A mathematical signal model for massive MIMO systems with centralized and distributed antennas in the future fifth generation (5G) heterogeneous cellular networks is also developed. A sum-rate analysis and a study of computational cost for DSD are also presented. Simulation results show excellent performance of the proposed DSD algorithm when combined with linear and SIC-based detectors. [pt] SISTEMA MIMO MULTIUSUARIO [pt] DETECCAO DESACOPLADA DE SINAIS [en] DECOUPLED SIGNAL DETECTION [en] VARIABLE LIST DETECTION
144	Högtempererat borrhålslager för fjärrvärme / High Temperature Borehole Thermal Energy Storage for District Heating Hallqvist, Karl January 2014 (has links) The district heating load is seasonally dependent, with a low load during periods of high ambient temperature. Thermal energy storage (TES) has the potential to shift heating loads from winter to summer, thus reducing cost and environmental impact of District Heat production. In this study, a concept of high temperature borehole thermal energy storage (HT-BTES) together with a pellet heating plant for temperature boost, is presented and evaluated by its technical limitations, its ability to supply heat, its function within the district heating system, as well as its environmental impact and economic viability in Gothenburg, Sweden, a city with access to high quantities of waste heat. The concept has proven potentially environmentally friendly and potentially profitable if its design is balanced to achieve a good enough supply temperature from the HT-BTES. The size of the heat storage, the distance between boreholes and low borehole thermal resistance are key parameters to achieve high temperature. Profitability increases if a location with lower temperature demand, as well as risk of future shortage of supply, can be met. Feasibility also increases if existing pellet heating plant and district heating connection can be used and if lower rate of return on investment can be accepted. Access to HT-BTES in the district heating network enables greater flexibility and availability of production of District Heating, thereby facilitating readjustments to different strategies and policies. However, concerns for the durability of feasible borehole heat exchangers (BHE) exist in high temperature application. / Värmebehovet är starkt säsongsberoende, med låg last under perioder av högre omgivningstemperatur och hög last under perioder av lägre omgivningstemperaturer. I Göteborg finns en stor mängd spillvärme tillgängligt för fjärrvärmeproduktion sommartid när behovet av värme är lågt. Tillgång till säsongsvärmelager möjliggör att fjärrvärmeproduktion flyttas från vinterhalvår till sommarhalvår, vilket kan ge såväl lönsamhet som miljönytta. Borrhålsvärmelager är ett förhållandevis billigt sätt att lagra värme, och innebär att berggrunden värms upp under sommaren genom att varmt vatten flödar i borrhål, för att under vinterhalvåret användas genom att låta kallt vatten flöda i borrhålen och värmas upp. I traditionella borrhålsvärmelager används ofta värmepump för att höja värmelagrets urladdade temperatur, men på grund av höga temperaturkrav för fjärrvärme kan kostnaden för värmepump bli hög. I denna rapport föreslås ett system för att klara av att nå höga temperaturer till en lägre kostnad. Systemet består av ett borrhålsvärmelager anpassat för högre temperaturer (HT-BTES) samt pelletspannor för att spetsa lagrets utgående fluid för att nå hög temperatur. Syftet med rapporten är att undersöka potentialen för detta HT-BTES-system med avseende på dess tekniska begränsningar, förmåga till fjärrvärmeleverans, konsekvenser för fjärrvärmesystemet, samt lönsamhet och miljöpåverkan. För att garantera att inlagringen av värme inte är så stor att priset för inlagrad värme ökar väsentligt, utgår inlagringen från hur mycket värme som kyls bort i fjärrvärmenätet sommartid. I verkligheten finns betydligt mer värme tillgänglig till låg kostnad. När HT-BTES-systemet producerar fjärrvärme, ersätts fjärrvärmeproduktion från andra produktionsenheter, förutsatt att HT-BTES-systemets rörliga kostnader är lägre. I Göteborg ersätts främst naturgas från kraftvärme, men också en del flis. Kostnadsbesparingen beror på differensen för total fjärrvärmeproduktionskostnad med och utan HT-BTES-systemet. Undersökningen visar att besparingen är större om HT-BTES-systemet placeras i ett område där det är möjligt att mata ut fjärrvärme med lägre temperatur. Om urladdning från HT-BTES kan ske med hög temperatur ökar också besparingen. Detta sker om lagrets volym ökar, om avståndet mellan borrhål minskar eller om värmeöverföringen mellan det flödande vattnet i borrhålen och berggrunden ökar. Dessa egenskaper för lagret leder också till minskade koldioxidutsläpp. Storleken på besparingen beror dock i hög grad på hur bränslepriser utvecklas i framtiden. Strategiska fördelar med HT-BTES-systemet inkluderar; minskad miljöpåverkan, robust system med lång teknisk livslängd (för delar av HT-BTES-systemet), samt att inlagring av värme kan ske från många olika produktionsenheter. Dessutom kan positiva bieffekter identifieras. Undersökningen visar att HT-BTES-systemet har god potential att ge lönsamhet och minskad miljöpåverkan, och att anläggning och drift av lagret kan ske utan omfattande lokal miljöpåverkan. Det har också visats att de geologiska förutsättningarna för HT-BTES är goda på många platser i Göteborg, även om lokala förhållanden kan skilja sig åt. För att nå lönsamhet för HT-BTES-systemet krävs en avvägning på utformning av lagret för att nå hög urladdad temperatur utan att investeringskostnaden blir för stor. Undersökningen visar att om anslutning av HT-BTES-systemet kan ske mot befintlig anslutningspunkt eller till befintlig värmepanna kan investeringskostnaden minska och därmed lönsamheten öka. Placering av HT-BTES-systemet i områden med risk för överföringsbegränsningar kan också minska behovet av att förstärka fjärrvärmenätet, och således bidra till att minska de kostnader som förstärkning av nätet innebär. Betydelsefulla parametrar för att nå lönsamhet för HT-BTES-system inkluderar dessutom kostnaden för inlagrad värme liksom vilket vinstkrav som kan accepteras. Tillgång till HT-BTES möjliggör ökad nyttjandegrad och flexibilitet för fjärrvärmeproduktionsenheter, och därmed ökad anpassningsmöjlighet till förändrade förutsättningar på värmemarknaden. Dock återstår att visa att komponenter som klarar de höga temperaturkraven kan tillverkas till acceptabel kostnad. HT-BTES BTES TES High Temperature Borehole Duct Thermal Energy Storage District Heating Seasonal Storage Storage Pellet Heat Plant Energy Power Flow Martes Environmental impact Finance Investment Cost Technology Drilling Saving Gothenburg Heat Transfer Bedrock Review Feasibility Study Load Peak load Base load District Heating Production Network Grid Pipe Borehole Heat exchanger Collector New Future Generation Low temperature Bottle neck System Successive calculation Matlab Computor programming Science HT-BTES BTES TES Borrhålslager Säsongslager Fjärrvärme Martes Värmelager Pellets Panna Energi Effekt Flöde Miljöpåverkan Ekonomi Investeringskostnad Teknik Borrning Besparing Göteborg Värmeöverföring Berggrund Review Förstudie Borrhål Last Spetslast Baslast Fjärrvärmeproduktion Hög temperatur Produktion Nät Rör Kollektor Borrhålsvärmeväxlare Ny Framtid Generation Låg temperatur Flaskhals System Successive kalkylering Matlab Data programmering Vetenskap
145	Les dates de naissance des créances / Dates of origination of claims Noirot, Renaud 28 November 2013 (has links) C’est le droit des entreprises en difficulté qui a permis de mettre en évidence la complexité que pouvait revêtir la détermination de la date de naissance des créances. Or, celle-ci apparaît fondamentale en droit privé. Constituant le critère d’application de certains mécanismes juridiques, elle incarne l’existence de la créance et représente dès lors un enjeu pour toute règle de droit ayant celle-ci pour objet ou pour condition. Deux courants doctrinaux s’opposent, la thèse classique fixe la date de naissance au stade de la formation du contrat, tandis que des thèses modernes la fixent au stade de l’exécution du contrat. La thèse matérialiste, fondée sur le droit des entreprises en difficultés, fait naître la créance de prix au fur et à mesure de l’exécution de la contre-prestation. La thèse périodique, reposant sur une réflexion doctrinale quant aux contrats à exécution successive, fait renaître toutes les créances du contrat à chaque période contractuelle. L’examen des thèses moderne à l’aune des mécanismes juridique qui ne peuvent qu’incarner la véritable date de naissance de l’authentique créance aboutit à leur invalidité. La thèse classique se trouve donc à nouveau consacrée. Mais la résistance que lui oppose le droit des entreprises en difficulté ne peut reposer sur la technique d’une fiction juridique, car d’autres manifestations du même phénomène peuvent être mises en évidence en dehors de ce domaine. Un changement de paradigme s’impose donc pour résoudre le hiatus. Derrière ce phénomène persistant se cache en réalité une autre vision, une autre conception de la créance, la créance économique qui vient s’articuler avec la créance juridique dans le système de droit privé pour le compléter. La dualité des dates de naissance recèle donc en son sein une dualité du concept de créance lui-même, la créance juridique classique et la créance économique. La créance économique n’est pas un droit subjectif personnel. Elle n’est pas la créance juridique. Elle n’est pas autonome de la créance juridique et ne doit pas être confondue avec une créance née d’un cas d’enrichissement sans cause. La créance économique représente la valeur produite par le contrat au fur et à mesure de l’exécution de sa prestation caractéristique. Elle permet de corriger l’application ordinaire du concept de créance juridique par en assurant la fonction de corrélation des produits et des charges d’un bien ou d’une activité. Ses domaines d’application sont divers. Outre son utilisation dans les droits comptable et fiscal, la créance économique permet la détermination de la quotité cédée dans le cadre d’une cession de contrat, la détermination du gage constitué par un patrimoine d’affectation dans le cadre de la communauté légale, de l’EIRL ou encore de la fiducie, ainsi que la détermination du passif exempté de la discipline d’une procédure collective. Dans ces domaines, ce n’est donc pas la date de naissance de la créance juridique qui s’applique, mais la date de naissance de la créance économique. La cohérence du système de droit privé se trouve donc ainsi restaurée quant à la date de naissance de la créance. / It is the laws governing companies experiencing difficulties which have revealed the complexity of determining the dates of the origination of the claims. And yet this appears to be fundamental in private law. As it constitutes the criterion for implementing certain legal mechanisms, it epitomizes the existence of the claim and hence represents a challenge for any rule of law in which the existence of this claim is a goal or condition. There are two conflicting doctrinal currents: the traditional approach sets the date of origination at the stage of the formation of the contract, while modern approaches situate it at the stage of the execution of the contract. The materialistic approach, based on the law governing companies experiencing difficulties, staggers the origination of the price debt over the period of the execution of the service. The periodical approach, which relies on a doctrinal reflection on successive execution contracts, is that of the re-origination of all the claims under the contract at each contractual period. An examination of the modern approaches, under the auspices of the legal mechanisms which can only epitomize the true date of origination of the authentic claim leads to the invalidity thereof. The traditional approach is therefore once again consecrated. But the resistance constituted by the laws governing companies in difficulty cannot rely on the technique of legal fiction, because other manifestations of the same phenomenon can be identified outside this domain. Therefore, a change of paradigm is in order if the hiatus is to be resolved. Behind this persistent phenomenon lies in fact another vision, another concept of the claim: the economic claim which, interwoven with the legal claim in the private law system, supplements it. The duality of the dates of origination therefore conceals in its bosom the duality of the very concept of a claim, the traditional legal claim and the economic claim. The economic claim is not a subjective personal right. It is not a legal claim. It is not autonomous of the legal claim and must not be confused with a claim originating in a case of unwarranted enrichment. The economic claim represents the value produced by the contract as the service which characterizes it is provided. It permits the rectification of the ordinary application of the concept of legal claim by ensuring the function of correlating the proceeds with the costs of a commodity or an activity. Its domains of application are varied. In addition to its use in accounting and fiscal law, the economic claim permits the determination of the portion transferred in the context of the transfer of a contract, the determination of the collateral consisting in a special-purpose fund in the context of a legal joint estate, a limited liability individual contractor or a trust, as well as the determination of the liabilities which escape the discipline of collective proceedings. In these domains, it is therefore not the date of origination of the legal claim which applies, but the date of origination of the economic claim. The coherence of the private law system is therefore restored as concerns the date of the origination of the claim. Créance Dette Obligation Germe de créance Ontologie de la créance Créance acquise Créance future Terme Condition Objet Cause Paiement Contrats Prix Loyer Responsabilité Préjudice Contrat à durée indéterminée Résiliation Résolution partielle Créance à exécution successive Cession de créance Saisie de créance Cession de contrat Déclaration d’insaisissabilité Cautionnement de créance future Sûreté sur créance future Patrimoine d’affectation Communauté légale PACS Indivision Fiducie EIRL Fonds de commerce Produits Charges TVA IS Fusion Apport partiel d’actif Cession de dette Défaisance Claim Debt Obligation Bilateral contract Sale Leases Case Estate Special purpose fund Collective proceedings Enforcement Transfer of claim Privilege of the separation of estates Procedural privilege Joint ownership Joint estate Trust Declaration of immunity of assets VAT Profit Proceeds Costs Chart of accounts Corporate Tax Industrial and Commercial Profits Endorsement of future claims Obligation of coverage Obligation to pay Legal standard 657.72
146	Automatic classiﬁcation of cardiovascular age of healthy people by dynamical patterns of the heart rhythm kurian pullolickal, priya January 2022 (has links) No description available. skew mean me- dian Engineering and Technology Teknik och teknologier

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