Dissertations / Theses: 'Flux capacity'

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Teepakorn, Chalore. "Numerical simulation and experimental study of membrane chromatography for biomolecule separation." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10299/document.

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La chromatographie membranaire est une alternative à la chromatographie classique sur résine basée sur le transport convectif des solutés à travers une membrane microporeuse plutôt que par le transport diffusif des solutés dans les particules de résines. Cette technique présente les avantages de diminuer les phénomènes de diffusion, de réduire les temps de séjour et les pertes de charge, et de permettre la purification rapide de quantités importantes de molécules. La chromatographie membranaire connaît un fort succès commercial. Une gamme importante de membranes chromatographiques mettant en jeu différents mécanismes de rétention (échange d’ions, affinité, etc.) et différentes géométries (feuille, spirale, etc.) est actuellement commercialisée. Malgré ce succès, différents aspects relatifs à la chromatographie membranaire restent mal connus. Cette thèse de doctorat se propose de répondre à certaines questions relatives à cette technique
Membrane chromatography (MC) is an alternative to traditional resin packed columns chromatography. The solute mass transport in the membrane occurs in convective through-pores rather than in stagnant fluid inside the pores of the resins particles, which is limited by the slow diffusive transport. MC offers the main advantage of reducing diffusion phenomena, shorter residence time and lowered pressures drops, and thus, facilitates rapid purification of large quantities of molecules. A wide range of chromatographic membranes involving different molecules retention mechanisms (ion exchange, affinity, etc...) is now commercialized. Despite their success, the influence of the geometry of the membrane chromatography devices remains relatively unexplored from a theoretical point of view. This doctoral thesis is aimed to clarify some ambiguous points related to this technique

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Palma-Lopez, David. "Contribution à l'étude des potentialités agricoles et des flux azotés dans divers sols cultivés en maïs." Vandoeuvre-les-Nancy, INPL, 1994. http://docnum.univ-lorraine.fr/public/INPL_T_1994_PALMA_LOPEZ_D.pdf.

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Ce mémoire à pour but principal d'esquisser une démarche afin de déterminer la potentialité agricole des sols pour une culture donnée et les relations de cette potentialité avec le devenir de l'azote engrais lors du cycle sol-plante. À partir d'études pédologiques de secteurs de références situés en Lorraine et à l'aide de classifications techniques des sols, nous avons mis en évidence les facteurs limitants de la production; ces derniers ont été comparés avec les rendements agricoles obtenus lors de trois années climatiques consécutives; il a été possible de définir après étude fréquentielle des paramètres climatiques, la potentialité agricole des sols pour une année donnée. De plus, il est nécessaire de tenir compte de l'hétérogénéité spatiale pour établir des plans de potentialités parcellaires. Le suivi des teneurs en nitrates dans les différents sols a mis en évidence les relations entre potentialités et risques d'entrainement des nitrates. L’emploi du traceur 15N révèle que les coefficients d'utilisation de l'azote engrais varient par rapport aux types de sols sans que l'on observe une relation précise entre CRU et CAU. Nous démontrons que les fournitures azotées des sols estimées à l'aide d'un témoin zéro présentent des relations étroites avec les valeurs Ndfs et A malgré des interactions avec l'engrais apporté. En conditions contrôlées, l'étude du cycle interne de l'azote 15 démontre l'absence d'effet ANI réel, elle indique des cinétiques des processus d'organisation-reminéralisation entre les divers compartiments azotés liés au comportement bio-physicochimique des sols, enfin elle montre que la fraction NSAnD constitue le siège principal de ces mécanismes, mais que la fraction NnH joue un rôle non négligeable pour certains types de sols

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Mate, Marin Ainhoa. "Multiscale approach to assess the DSM-flux capacity to mitigate impacts on the receiving waters : Quantification of overflow rates and interception of particulate pollutants from combined sewer overflows." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI008/document.

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Au cours des dix dernières années, les gouvernements de l'Union Européenne ont été encouragés à collecter des données sur le volume et la qualité de tous les effluents d'eaux urbaines ayant un impact environnemental significatif sur les milieux aquatiques récepteurs. Les méthodes de surveillance de ces flux nécessitent des améliorations, en particulier pour les déversoirs d’orage, structures complexes responsables en grande partie de la dégradation de la qualité des milieux récepteurs. Le DSM-flux (Dispositif pour la surveillance et maîtrise des flux d'eaux et polluants des réseaux d'eaux pluviales et unitaires) est un nouveau dispositif préfabriqué et pré-étalonné qui garantit les conditions hydrauliques appropriées permettant de mesurer les débits et volumes déversés ainsi que les concentrations et masses de polluants qui y sont transportés. Dans cette thèse, une relation permettant de mesurer le débit au passage du DSM-flux a été construite grâce à une étude expérimentale sur modèle physique réduit, puis validée pour plusieurs configurations d'écoulement à l'amont du dispositif. Quelles que soient les conditions hydrauliques en amont, les incertitudes relatives sont inférieures à 15% et 2% pour les débits et les volumes étudiés, respectivement, ce qui reste équivalent, voire mieux, par rapport aux incertitudes des méthodes actuelles les plus fiables. La méthode de mesure a été validée in situ sur un dispositif à grande échelle construit sur le terrain et fonctionnant en conditions réelles, ce qui montre la robustesse de la méthode. De plus, grâce à sa conception originale, le DSM-flux favorise l'interception d'une fraction des polluants particulaires. L’hydrodynamique de ce dispositif de mesure a été analysée ainsi que les conditions qui engendrent la décantation des polluants particulaires. En fonction des conditions d'écoulement, ce dispositif peut retenir 50% de la masse totale des matières solides fines en suspension transitant par le dispositif, mais pour des écoulements à débits élevés, cette efficacité est significativement réduite. Sa capacité de rétention a été aussi observée sur le terrain et une méthodologie a été élaborée pour quantifier son efficacité de rétention lors d'études futures. Mise à part sa performance hydraulique, du point de vue opérationnel, le dispositif présente d’autres avantages par rapport à d’autres dispositifs existants : (i) il est pré-étalonné et peut être installé à l’aval de déversoirs d’orage déjà existants, (ii) il peut s’insérer directement au sein du canal de décharge (installation d’un regard de visite équipé d’un DSM), (iii) sa performance hydraulique est indépendante des conditions de l’écoulement à l’amont et (iv) il s’agit d’un dispositif intégré de mesure de débits et de leur qualité simultanément, en plus d’intercepter une partie de polluants particulaires
Over the past decade, European Union governments have encouraged to collect data on the volume and quality of all urban water effluents with a significant environmental impact on receiving aquatic environments. Methods for monitoring these flows require improvements, particularly for combined sewer overflows, which are complex flows that contribute in significant proportion to the degradation of the quality of the receiving waters. The DSM-flux (Device for Stormwater and combined sewer flows Monitoring and the control of pollutant fluxes) is a new pre-calibrated and pre-designed device that guarantees the appropriate hydraulic conditions for measuring discharged flows and volumes as well as the concentrations and mass loads of pollutants carried in suspension by the flow. In this PhD work, a relationship allowing to measure the flow rates conveying through the DSM-flux was determined thanks to an experimental study on a small-scale physical model, and then validated for several flow configurations upstream of the device. Whatever the upstream hydraulic conditions are, the relative uncertainties are less than 15% and 2% for the flow rates and volumes studied, respectively, which is equivalent to the uncertainties of the most reliable current methods. The monitoring methodology was validated in situ in a large-scale device installed at the field and operating in real conditions, which shows the robustness of the method. Moreover, thanks to its original design, the DSM-flux allows the interception of a fraction of particulate pollutants. The hydrodynamics of this monitoring device were analysed as well as the conditions that cause the settling of particulate pollutants. Depending on the flow conditions, this device can retain 50% of the total mass of fine suspended solid matter transiting through the device, but for flows at high discharge rates, this efficiency is significantly reduced. Its retention capacity has also been observed in the field and a methodology has been developed to quantify its retention efficiency in future studies. Apart from its performance, from an operational point of view, the device has other advantages compared to other current devices: (i) it is pre-calibrated and can be installed downstream from existing combined sewer overflows, (ii) it can be directly installed through a manhole in the discharge channel, (iii) its hydraulic performance is independent from the flow conditions upstream, and (iv) it is an integrated monitoring device, measuring flow rates and their quality simultaneously, in addition to intercepting a part of the particulate pollutants

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Shen, Meicheng. "Statistical Estimation of Vegetation Production in the Northern High Latitude Region based on Satellite Image Time Series." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1563552594966495.

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Assaf, Mounir. "From qualitative to quantitative program analysis : permissive enforcement of secure information flow." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S003/document.

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De nos jours, les ordinateurs sont omniprésents. Tous ces ordinateurs stockent et manipulent de l'information, parfois sensible, d'où l'intérêt de protéger et de confiner la dissémination de cette information. Les mécanismes de contrôle de flux d'information permettent justement d'analyser des programmes manipulant de l'information sensible, afin de prévenir les fuites d'information. Les contributions de cette thèse incluent des techniques d'analyse de programmes pour le contrôle de flux d'information tant qualitatif que quantitatif. Les techniques d'analyse qualitatives permettent la détection et la prévention des fuites d'information. Les techniques quantitatives permettent d'estimer ces fuites afin de décider si elles sont négligeables
Computers have become widespread nowadays. All these computers store and process information. Often, some of this information is sensitive; hence the need to confine and control its dissemination. An important field in computer science, that is concerned about analysing programs in order to confine and control the release of sensitive information, is the information flow control field. The contributions of this thesis include program analysis techniques for qualitative and quantitative information flow control. Qualitative techniques aim at detecting and preventing information leaks. Quantitative techniques go beyong the detection of information leaks, by estimating the leakage in order to decide whether it is negligeable

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Mhiri, Emna. "Planification de la production à capacité finie dans un contexte à forte variabilité, application à l'industrie des semi-conducteurs." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAT066/document.

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L'industrie des semi-conducteurs est caractérisée par une production de forte variabilité et de faible volume, des flux de production ré-entrants ainsi que d'un processus de fabrication complexe. Au sein de ce contexte industriel complexe, a été considéré un problème de planification à capacité finie. C'est le problème de projection des encours de production et des commandes clients à capacité finie. Il s'agit d’estimerles dates de début, les temps d'attente et les dates de fin de chacun des steps des différents lots ainsi que la charge accumulée sur les équipements. Cette projection doit tenir compte des contraintes de capacité et qualifications des équipements et des dates d'échéance de livraison des lots. La contrainte de qualification définit l'éligibilité d'un équipement à traiter un produit. Ainsi, l'objectif de cette étude consiste à établir un plan de production réalisable à moyen terme. Afin de réaliser cet objectif, des méthodes exactes et approchées sont proposées. Des résultats en termes de complexité, et d'algorithmes de résolution, ont permis une application industrielle, dans la mesure où un logiciel de planification de la production à capacité finie a été développé
In this study, we consider the problem of production planning in the semiconductor industry characterized by high mix low volume production, reentrant flows and complex manufacturing process.The aim of this work is to establish a feasible production schedule that takes into account the limited capacity of the manufacturing system, equipment qualifications constraints and delivery due dates. In this context, we have formulated the objective and constraints in a mixed linear program (MIP). The objective of the MIP is to minimize delivery delays to guarantee on-time delivery. While executing different tests of the MIP, we have reached a limit of resolution in a reasonable time. Thus, we use an approximate method to solve the problem. The results show the effectiveness of the heuristic established as solution quality and time resolution.The obtained results led to an industrial application and a software that provides feasible schedules in reduced execution time in a specific fab

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Erostate, Mélanie. "Dynamique spatio-temporelle des flux naturels et anthropiques vers les hydrosystèmes littoraux tributaires des eaux souterraines : Investigations isotopiques et géochimiques pour la compréhension des interactions aquifères-lagune sur le site de Biguglia (Haute-Corse)." Thesis, Corte, 2020. http://hal-univ-corse.archives-ouvertes.fr/view_by_stamp.php?&action_todo=view&id.

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L’anthropisation grandissante des bassins versants côtiers représente une menace importante pour les eaux souterraines et les écosystèmes qui en dépendent, alors appelés « écosystèmes tributaires des eaux souterraines ». A l’image de l’hydrosystème de Biguglia (Corse), l’urbanisation rapide et désorganisée ainsi que les activités industrielles et agricoles développées sur la plaine de la Marana sont autant de sources de dégradation des eaux souterraines. Cette ressource, pourtant stratégique et utilisée pour l’alimentation en eau potable de la région bastiaise, présente aujourd’hui les marqueurs d’une contamination multiple et diffuse sur l’ensemble de la plaine. En plus d’être problématique pour les besoins en eau humains, la dégradation qualitative des eaux souterraines de l’aquifère de la Marana, constitue également une menace pour l’écosystème fragile de la lagune de Biguglia et la pérennité des services écosystémiques qu’il prodigue. Dans ce contexte de pressions croissantes, la connaissance approfondie du fonctionnement de l’hydrosystème de Biguglia s’impose comme un élément essentiel pour garantir une gestion durable de la ressource en eau. Dans ce but, une approche multi-traceurs géochimiques et isotopiques a été développée afin notamment de mieux contraindre l’état de la ressource, les conditions hydrodynamiques et la nature des interactions aquifères-rivières-lagune. L’étude des isotopes stables de la molécule d’eau (18O, 2H) a mis en évidence la complexité de la recharge. L’aquifère de la Marana bénéficie d’une recharge autochtone par l’infiltration directe des précipitations sur la plaine et d’une recharge allochtone par les précipitations en provenance des contreforts schisteux. A ces mécanismes, s’ajoute également la recharge prodiguée par l’infiltration des eaux du Bevincu et du Golu et la contribution latérale des eaux en provenance des contreforts schisteux de la Corse alpine. Le modèle de mélange développé (18O, Cl- et HCO3-) a permis une estimation semi-quantitative des mélanges. Il démontre la complexité du fonctionnement de l’aquifère, avec une différence notable de la contribution des contreforts schisteux en fonction de la localisation et de la profondeur de la ressource. Il apparaît également de manière claire que la lagune de Biguglia est partiellement tributaire des eaux souterraines. La plaine de la Marana est sujette à une dégradation qualitative liée à la présence excessive de nitrates (NO3-) et de micropolluants organiques. D’après les isotopes du NO3- (15N-NO3-, 18O-NO3-) et du Bore (11B), les principales sources d’azote sont le sol et les eaux usées. La corrélation entre concentrations en NO3- et temps de résidence des eaux (3H et CFCs) a mis en avant la capacité de stockage et d’archivage des eaux souterraines de l’aquifère de la Marana. Mise au regard de l’évolution de l’occupation des sols sur la plaine, la modification progressive des sources azotées enregistrée dans l’aquifère a permis de retracer la trajectoire socio-environnementale de l’hydrosystème de Biguglia. L’état contemporain dégradé de la ressource découle en grande partie de l’héritage des pollutions liées aux activités humaines historiques. Le modèle conceptuel élaboré grâce à ces travaux apporte de nouveaux éléments de compréhension qui pourront aider à l’instauration de stratégies de gestion pertinentes, assurant la pérennité future des ressources en eau et des services écosystémiques qui en dépendent
The exacerbated anthropization of coastal hydrosystems poses a significant threat to groundwater and ecosystems that depend on it, then called "groundwater-dependent ecosystems". Like the Biguglia hydrosystem (Corsica, France), rapid and disorganized urbanization, as well as industrial and agricultural activities developed on the Marana plain are major sources of groundwater degradation. This strategic resource, used for the drinking water supply of the Bastia urban area, presents the markers of multiple and diffuse contaminations. In addition to being problematic for human water needs, the groundwater qualitative degradation of the Marana aquifer also constitutes a threat to the fragile ecosystem of the Biguglia lagoon and the sustainability of the ecosystem services it provides. In this context of increasing pressures, a strong knowledge of the Biguglia hydrosystem behavior is essential to ensure sustainable management of water resources. To this end, a multi-tracer geochemical and isotopic approach has been developed in order to better constrain the state of the groundwater resource, the hydrodynamic conditions and the nature of aquifer-river-lagoon interactions. The study of the stable isotopes of the water molecule (18O, 2H) has highlighted the recharge complexity. The Marana aquifer benefits from an indigenous recharge through direct infiltration of precipitation on the plain and an allochthonous recharge through precipitation from the schistous reliefs. The infiltration of river water from the Bevincu and Golu rivers and the lateral contribution of water from the schistous reliefs also contribute to the aquifer recharge. The developed mixing model (18O, Cl- and HCO3-) allowed a semi-quantitative estimation of the mixing processes. It demonstrates the complex aquifer behavior, with a significant difference in the contribution of schistous groundwater depending on the location and depth of the resource. It is also clear that the Biguglia lagoon is partially dependent on groundwater. The Marana plain is subject to qualitative degradation due to the excessive presence of nitrates (NO3-) and organic micropollutants. According to the NO3- (15N-NO3-, 18O-NO3-) and Boron (11B) isotopes, the main sources of nitrogen are soil and wastewater. The correlation between NO3- concentrations and water residence time (3H and CFCs) highlighted the storage and the groundwater archiving capacity. With regard to the evolution of land use, the progressive modification of the nitrogen sources recorded in the aquifer made it possible to trace the socio-environmental trajectory of the Biguglia hydrosystem. The contemporary degraded state of the resource mainly results from the pollution legacy linked to historical human activities. The conceptual model developed provides new elements that can help towards the implementation of relevant management strategies, to ensure the sustainability of water resources and associated ecosystem services

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Baroche, Thomas. "Marchés pair-à-pair de l’électricité dans les réseaux électriques." Thesis, Rennes, École normale supérieure, 2020. http://www.theses.fr/2020ENSR0022.

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Le déploiement de ressources énergétiques distribuées, combiné à une gestion plus pro-active de la demande et à l'intégration de systèmes de gestion d'énergie, fait entrer l'exploitation des systèmes électriques et des marchés de l'électricité dans un nouveau paradigme. En partie liés à leur structure décentralisée, les marchés dits pair-à-pair ont gagné un intérêt considérable. Les marchés pair-à-pair reposent sur des négociations bilatérales entre les agents pour faire correspondre l'offre et la demande. De plus, ils peuvent cartographier l’ensemble des échanges possibles, ce qui permet de repenser ces interactions avec le réseau.Ces travaux de thèse traitent de trois défis majeurs dont la résolution est essentielle avant d'envisager le passage à des applications réelles : (i) le passage à l'échelle pour gérer un nombre croissant d'acteurs et de ressources distribués, (ii) le respect des contraintes du réseau électrique, et (iii) la résilience du marché à la présence d'agents stochastiques. Une analyse de complexité a permis de montrer que le passage à l’échelle des marchés pair-à-pair et le mécanisme de résolution peut être renforcé par trois améliorations réduisant les complexités algorithmiques et structurelles. Pour le respect des contraintes réseau, le manuscrit propose d’introduire des redevances qui seraient liées à l’utilisation du réseau électrique. Deux approches sont considérées pour déterminer ces redevances réseau. La première, exogène, exige que le gestionnaire de réseau les fournisse a priori avant le début des négociations. Dans la seconde, le gestionnaire de réseau actualise les redevances réseau de manière endogène à chaque itération pour mieux tenir compte de l'état actuel du réseau. Enfin, les prévisions de production et de consommation des agents stochastiques sont mieux prises en compte par la création d’un marché pair-à-pair de l'énergie et des capacités de réserve, pour corriger un éventuel déséquilibre de puissance due à des erreurs de prévision
The deployment of distributed energy resources, combined with a more proactive demand side management and energy management systems, is inducing a new paradigm in power system operation and electricity markets. Within a consumercentric market framework, peer-to-peer approaches have gained substantial interest. Peer-to-peer markets rely on multi-bilateral negotiation among all agents to match supply and demand. These markets can yield a complete mapping of exchanges onto the grid, hence allowing to rethink market–grid interactions.This thesis treats three main challenges which needs to be overcome before considering real world implementations: (i) scalability to host a growing number of distributed users and resources, (ii) compatibility with grid constraints, and (iii) resilience to stochastic power injections. After a complexity analysis, scalability of peer-topeer markets and the proposed negotiation mechanism to solve them is enhanced by three improvements reducing algorithmic and structural complexities. Feasibility of the peer-to-peer electricity market is eventually obtained with the use of network charges. Two approaches are proposed to handle these network charges. The first, exogenous, requires the system operator to provide them a priori before negotiations start. In the second, the system operator updates network charges endogenously at each iteration to better account for the current grid status. Finally, power forecasts of stochastic agents are taken in a more comprehensive way by the developpement of peer-to-peer market on both energy and capacities, used to restore power balance in case of misdipatch due to forecast errors

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Průša, David. "Identifikace tepelné vodivosti a tepelné kapacity stavebních látek metodou „Hot Wire Method“." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-392340.

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This aim of task deals with study of heat dissipation mechanisms and the description of physical phenomena, which is accompanied by non-stationary measurement of thermal characteristics by the method "hot-wire method". In particular, we observe the coefficient of thermal conductivity and its dependence on various variables such as the temperature of the measured sample, its moisture state, the volume of the sample and its porosity. The above mentioned findings are used for the invention of the measuring device of a nonstationary gauge, which is based on regular heating and is dedicated to measuring the thermal conductivity coefficient and the heat capacity by the "hot-wire method" method. In the last part of the thesis is verified functionality of the proposed measuring device, the suitability of the created algorithm for the processing of the measured data and the evaluation of the results was verified. The reproducibility of the measurements was verified and the measured results were compared with the measurement methods, which are commonly used. the influence of humidity on the coefficient of thermal conductivity.

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Pavelka, Tomáš. "Provozní vlastnosti LED a jejich modelování." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-263352.

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Doctoral thesis deals with parameters of LED light sources and their static and dynamic changes due to variable operational conditions. Firstly there is briefly described the history of light emitting diodes, that brought LED from unintentional observation of luminescence to light source, which is generally used through the whole area of lighting techniques. Thesis focuses on light parameters analysis, which are specific for semiconductor light sources and their mutual relations. These relations in compliance with understanding the principles of light emission in semiconductor light sources enable establishing of basic connections and effects usable for LED behaviour model. Mutual relations of LED parameters and influencing factors are verified by measurement of chosen testing samples. For deeper understanding of diode parameter influencing mechanisms there are analysed current degradation models including degradation of partial components. On the basis of these facts there is created a model of LED luminaire operating with LED parameters together with cooling system that represent the integral part of the luminaire. Impact of supply drivers is also studied, because they are necessary for LED operation. Designed model supports the area of static changes of light parameters, as well as the dynamic changes of output parameters. Presented model is verified by testing measurements at basic operational states and partially outside of the common operational limits. There are also presented the possibilities of real use of the model that involve the evaluation of designed luminaire for specific light sources, searching for optimal operational limits, optimization of luminaire heatsink or using public lighting systems for regulation of electricity grid load fluctuations.

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Paula, Francisco Suliano Mesquita. "Proposta de adaptação da metodologia do highway capacity manual 2000 para análise de vias arteriais urbanas em Fortaleza." reponame:Repositório Institucional da UFC, 2006. http://www.repositorio.ufc.br/handle/riufc/4876.

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PAULA, F. S. M. Proposta de adaptação da metodologia do highway capacity manual 2000 para análise de vias arteriais urbanas em Fortaleza. 2006. 158 f. Dissertação (Mestrado em Engenharia de Transportes) – Centro de Tecnologia, Universidade Federal do Ceará, Fortaleza, 2006.
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Arterial streets are responsible for the vast majority of the transient traffic in large Brazilian cities, thus their adequate supervision is a major concern in order to maintain acceptable levels of mobility in the network. The Highway Capacity Manual – HCM 2000 is a manual produced by United States transportation agencies providing methodologies for the assessment of the level ofservice and to estimate the capacity of several components of the traffic system, including a specific section regarding urban streets analysis. This methodology is divided in two methods: 1st Method – Street class determination; 2nd Method – Level of service assessment; and 3rd Method – Simulation of the space average speed . In this work, however, the assumed research hypothesis has considered this methodology to be inappropriate to the Brazilian reality due to differences in the physical-operational aspects of the network as well as differences in drivers behaviour characteristics. Consequently, this research aimed to verify the feasibility of the HCM 2000 methodology to arterial streets of Fortaleza and suggest adjustments to improve its effectiveness vis-à-vis the quality assessment of the transient traffic corridors in this city. Conceptual debates were complemented by the quantitative analysis of a 15 sample dataset obtained from the most important traffic corridors in Fortaleza. As a result, adjustments in the two first methods were suggested and the 3rd method was found to be recommended for planning analysis purpose only. The findings in this research are expected to contribute for the further development of a fully national methodology that would able to accurately reflect the Brazilian urban arterial streets traffic scenario.
As vias arteriais são responsáveis pelo deslocamento da maioria do tráfego de passagem nas grandes cidades brasileiras, tornando prioritário o gerenciamento desses corredores com o intuito de manter níveis aceitáveis de fluidez do tráfego veicular. O Highway Capacity Manual– HCM 2000 é um manual americano que contém metodologias para a avaliação do nível deserviço e estimação da capacidade de diversos elementos do sistema viário, incluindo uma específica para a análise de vias urbanas. Essa metodologia pode ser dividida em três métodos: 1o Método – Determinação da classe da via; 2o Método – Estimação do nível de serviço; e 3o Método – Simulação da velocidade média de percurso. Neste trabalho, entretanto, considerou-se como hipótese de pesquisa que essa metodologia não é adequada à realidade brasileira, devido às diferenças existentes tanto em relação às características físico-operacionais do sistema viário, quanto ao comportamento dos seus usuários. Portanto, esta pesquisa de dissertação objetivou verificar a adequabilidade da metodologia do HCM 2000 às vias arteriais de Fortaleza, propondo adaptações para torná-la mais eficaz na avaliação da qualidade do tráfego de passagem nos corredores arteriais dessa cidade. As discussões conceituais foram complementadas por análises quantitativas dos dados de uma amostra de 15 dos principais corredores de Fortaleza, resultando em propostas de alteração nos dois primeiros métodos, além de recomendação de utilização do 3º Método apenas em análises de planejamento. Espera-se que as conclusões deste estudo contribuam para o futuro desenvolvimento de uma metodologia genuinamente nacional que retrate com precisão a realidade do tráfego nas vias arteriais urbanas brasileiras.

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Liu, Tian. "Manoeuvre contrôlée des transformateurs de puissance avec flux rémanent." Phd thesis, Supélec, 2011. http://tel.archives-ouvertes.fr/tel-00631516.

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Le transformateur de puissance est un équipement essentiel d'un réseau électrique et le plus coûteux dans les postes. Pour augmenter son degré de disponibilité et de fiabilité, il est nécessaire d'appliquer la manœuvre contrôlée afin de diminuer la saturation du noyau lors de l'enclenchement, et donc limiter les courants d'appel. Ces derniers sont asymétriques, d'amplitude élevée, et riches en harmoniques. Ils peuvent causer des effets indésirables comme le disfonctionnement des dispositifs de protections, l'endommagement mécanique des enroulements du transformateur et réduire en général la durée de vie et la qualité des systèmes. Une technique efficace pour réduire ces courants d'appel est de mettre sous tension le transformateur quand le flux dynamique généré par la source est égal à son flux rémanent. Un modèle simplifié du transformateur de puissance est adopté pour l'analyse des phénomènes physiques liés à l'application des manœuvres. Pour évaluer le degré de faisabilité de cette technique, des simulations sont effectuées en utilisant le simulateur de réseau EMTP. Les contraintes requises pour chacun des composants du système de manœuvre contrôlée comme les segments de ligne, les disjoncteurs sont étudiées en détail pour déterminer l'algorithme de calcul de l'instant optimal de manœuvres. Ensuite des tests de validation statistiques sont effectués afin d'évaluer les performances des différentes approches employées. Enfin une étude consacrée à la reconstitution du flux rémanent via un transformateur capacitif de tension (TCT) est menée pour appliquer l'algorithme de manœuvre contrôlée dans les postes en utilisant les équipements de mesure déjà existants.

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Gong, Yuxuan. "Dielectric and Structural Study of Bi2O3-BaO-CuO Glass Flux Additives Sintered Barium Titanate for Multilayer Capacitor Applications." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1368086374.

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Andrews, Gary Lyndl. "Synthesis and characterization of Ceria with an optimal oxygen storage capacity as potential medium to remove SO2 from flue gas emissions." Thesis, University of Western Cape, 2013. http://hdl.handle.net/11394/3323.

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Magister Philosophiae - MPhil
Due to an increasing demand for energy, alternative renewable energy sources are investigated globally. However fossil fuels are still one of the main energy sources. The combustion of these fuels produces by-products such as SOx, NOx and CO2, which have detrimental effects on the environment and human health. Therefore, effective methods are needed to minimize the pollution and affects that these by-products cause. Catalysts are commonly employed to convert these by-products to less harmful and/or resalable products. Ceria and ceria based materials are good candidates for the removal and conversion of SOx and NOx. Ceria and ceria related materials are most effective as catalysts when they are in the nano-form with good crystallinity and nanoparticles that are uniform. The growth of nanoparticles is preceded by a nucleation process which can occur by solid-state restructuring of a gel or precipitation from a saturated solution. The precipitation method was selected to synthesize Ceria nanoparticles. Synthesis conditions such as temperature, solution type and ageing time and their effect on the physical and chemical forms of the Ceria particles were investigated. The morphology and structural properties were investigated using Scanning Electron Microscopy, X-ray diffraction and Transmission Electron Microscopy. X-ray Photoelectron Spectroscopy was used to investigate the chemical properties. It was found that low temperatures, low base volume and a solvent with a small dielectric constant favor the formation of small crystallites with a relatively large concentration of defects. These defects are desirable since they enhance the catalytic activity of ceria.

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Andrino, Jeane Maria Cunha Machado. "Desempenho de sistemas de extração e análises em fluxo explorando fluxo pulsado e leito fluidizado." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-23102017-161746/.

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O emprego de sistemas em fluxo com multi-impulsão são destaques quanto ao volume de efluentes gerados e a possibilidade de mecanização, operando em condições dinâmicas. A utilização de microbombas solenoide é potencial em processos de adsorção/dessorção de analitos, pois desempenham o fluxo pulsado, e quando operadas em conjunto com o estabelecimento da condição de leito fluidizado, contribuem para o aumento da eficiência de adsorção/dessorção. O objetivo geral deste trabalho foi desenvolver e avaliar sistemas de extração sólido-líquido e análises química em fluxo, explorando fluxos pulsados e o estabelecimento da condição de leito fluidizado, visando melhorar a eficiência de interação da amostra e reagente. Para tanto, foram desenvolvidos sistemas em fluxo com multi-impulsão associados ao uso de colunas de leito fluidizado. 1) Sistema para determinação da capacidade de adsorção de fósforo; determinação do fósforo remanescente (P-rem) em solos; 2) Sistema para determinação da capacidade de troca catiônica (CTC) de solos, avaliando a adsorção e a dessorção de analitos. Foi demonstrado que o fósforo e o cálcio contidos em solução são eficientemente adsorvidos/dessorvidos pelo solo, reduzindo significativamente os efeitos de aumento de pressão com o estabelecimento do leito fluidizado (fluidização pulsada) nas colunas contendo 50 mg de amostras de solo. A substituição do fluxo pulsado (microbomba solenoide) pelo fluxo contínuo (bomba peristáltica) limitou a interação sólido-líquido, pois estabeleceu caminhos preferenciais, desfavorecendo as condições de mistura. A utilização das microbombas solenoide em conjunto com a fluidização das amostras de solo, apresentou vantagens quanto à diminuição da quantidade de massa de solo requerida (entre 100 e 200 vezes), redução do consumo de reagentes e resíduos gerados (40 vezes), demonstrando o potencial do sistema em fluxo proposto por ser uma alternativa ambientalmente adequada. Os sistemas propostos são versáteis e facilmente adaptados para outros estudos de extração
Multi-pumping flow systems are highlights on the volume of effluents generated and mechanization, operating in dynamic conditions. Solenoid micro-pumps are potential in the analyte adsorption/desorption processes, because they play the pulsed flow and when operated in conjunction with the establishment of the fluidized bed condition, contribute to the increase of the adsorption/desorption efficiency. The objective of this work was to develop and evaluate solid-liquid extraction and flow analysis systems, exploring pulsed flows and establishing the fluidized bed condition in order to improve the solid-liquid interaction efficiency. It was developed multi-pumping flow systems associated with the establishment of the fluidized bed columns. 1) System for determination of phosphorus adsorption capacity; determination of the remaining phosphorus (P-rem) in soils; 2) System to determine the cation exchange capacity (CEC) of soils, evaluating the adsorption and desorption of analyte. It has been shown that the phosphorus and calcium contained in solution are efficiently adsorbed/desorbed by the soil, significantly reducing the effects of pressure increase with the establishment of the fluidized bed (pulsed fluidization) in the columns containing 50 mg of soil samples. The substitution of the pulsed flow (solenoid micro-pump) by the continuous flow (peristaltic pump) limited the solid-liquid interaction, since it established preferential pathways, undermining the mixing conditions. The use of the solenoid micro-pumps in conjunction with the fluidization of the soil samples presented advantages in terms of decreasing the amount of soil mass required (between 100 and 200-fold time), reducing the consumption of reagents, solutions and waste production (40-fold time), demonstrating the potential of this system to be an environmentally friendly alternative. The proposed systems are versatile and easily adapted to other extraction studies

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Niel, Romain. "Effets métaboliques et physiologiques d’un entraînement en accélération chez la souris âgée et effets de l’âge sur les capacités physiques de la souris déficiente à la créatine kinase." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLE028/document.

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La quête de l’augmentation de l’espérance de vie chez l’homme inspire depuis longtemps les travaux de recherche, en particulier en biologie. Au-delà de la notion de mortalité, celles de la morbidité et de l’espérance de vie active et indépendante sont aujourd’hui au centre des enjeux de santé publique. En effet, la perte d’autonomie chez les personnes âgées nous oriente vers un objectif d’amélioration de l’espérance de vie en bonne santé. L’activité physique est un facteur fondamental du bien-être de l’individu, impactant aussi bien les performances physiques que les diverses pathologies (diabètes, pathologies cardiaques). Chez la population âgée, la nécessité d’obtenir des résultats rapides, sans souffrance ni longs entraînements nous a mené à notre première étude. Celle-ci a porté sur l’application d’un nouveau protocole d’entraînement à court terme utilisant l’accélération chez les souris âgées. Les résultats obtenus nous ont montré une amélioration des performances physiques et de l’ensemble des métabolismes énergétiques, tout en étant plus efficient qu’un entraînement en endurance et plus adapté qu’un entraînement en intervalles. De plus, devant l’intérêt récent que suscitent les transferts énergétiques dans la régulation des métabolismes énergétiques et dans le processus du vieillissement, nous nous sommes intéressés à la compréhension des mécanismes des flux énergétiques, et notamment à celui faisant intervenir la créatine kinase mitochondriale. Notre seconde étude a ainsi analysé les capacités physiques et physiologiques de souris déficientes à la créatine kinase mitochondriale de 6 à 18 mois. Nos résultats suggèrent une utilisation majoritaire du métabolisme lipidique et un maintien des capacités physiques chez ces souris déficientes à la créatine kinase mitochondriale. La compréhension des mécanismes du flux énergétique et de leur importance sur les capacités physiques au cours du vieillissement permettrait de mieux concevoir les futurs protocoles d’entraînement, tel que l’entraînement en accélération nous ouvrant de nouvelles perspectives dans l’amélioration des capacités physiques et de l’autonomie au cours du vieillissement
For a long time, the increase in life expectancy in humans inspires research, especially in biology. Beyond the notion of mortality, those of morbidity and active and independent life expectancy are at the center of public health issues. However, faced with the decrease in physical capacity and the increase in the number of diseases during aging, interest is now focused on improving the quality of life. Indeed, the loss of autonomy in the elderly directs us towards a goal of improving the healthspan. Physical activity is a fundamental factor in the well-being, impacting physical performance as well as different pathologies (diabetes, cardiac pathologies). In the elderly population, the necessity to reach fast results, without suffering or long time training led to our first study. This one focused on a new model of short acceleration-based training protocol in elderly mice. The results showed an improvement in physical performance and in the whole of the energetic metabolisms, while being more efficient than endurance training and more suitable than interval training. Moreover, given the recent interest in energy transfers in the regulation of energetic metabolisms and in the aging process, we were interested in understanding the mechanisms of energy flux and in particular the one involving mitochondrial creatine kinase. Our second study analyzed the physical and physiological capacity of mitochondrial creatine kinase deficient mice from 6 to 18 months. Our results suggest a predominant lipid metabolism and showed a conservation of physical abilities in these mitochondrial creatine kinase deficient mice. Knowledge of the mechanisms of energy flux and their importance to physical capacities during aging would lead to better design future training protocols, such as our acceleration training, which opens new perspectives in improvement of physical capacity and autonomy during aging

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Dequeant, Kean. "Modélisation de la variabilité des flux de production en fabrication microélectronique." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI042/document.

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Dans un contexte où l’industrie du semi-conducteur explore de nouvelles voies avec la diversification des produits et le paradigme de « More than Moore », les délais de livraison et la précision de livraison sont des éléments clés pour la compétitivité d’entreprises de semi-conducteur et l’industrie 4.0 en général. Les systèmes de production sont cependant sujets à de la « variabilité », qui crée des embouteillages dans la production de manière incontrôlée et imprévisible. Cette thèse CIFRE (partenariat entre le laboratoire GSCOP et STMicroelectronics) s’attaque à ce problème de la variabilité dans la fabrication en environnement complexe. La première partie de cette thèse offre une étude approfondie de la variabilité: nous mettons d’abord en avant les conséquences de la variabilité pour mieux la définir, puis nous clarifions que la variabilité concerne les flux de production en introduisant la notion de variabilité des flux de production et en apportant des éléments de mesure associés, et nous clôturons cette première partie par l’étude des sources de variabilité à travers une étude bibliographique et des exemples industriels. La seconde partie est dédiée à l’intégration de la variabilité dans les outils de gestion de production: nous montrons comment une partie des conséquences peut être mesurée et intégrée aux projections d’encours pour améliorer le contrôle et la prévisibilité de la production, proposons un nouvel outil ((the WIP Concurrent) pour mesurer plus précisément les performances des systèmes en environnement complexe, et mettons en avant des effets de dépendances prépondérants sur la variabilité des flux de production et pourtant jamais pris en compte dans les modèles. La troisième et dernière partie de la thèse couvre les perspectives de réduction de la variabilité : en se basant sur les éléments présentés dans la thèse, nous proposons un plan pour réduire la variabilité des flux de production sur le court terme, et une direction pour la recherche à moyen et long terme
In the context of Industry 4.0 and the More than Moore’s paradigm, delivery precision and short cycle times are essential to the competitiveness of High Mix Low Volume semiconductor manufacturing and future industries in general. So called “variability” however creates uncontrolled and unpredictable “traffic-jams” in manufacturing systems, increasing cycle times and decreasing the systems’ tractability. This research, a CIFRE PhD between the GSCOP laboratory and STMicroelectronics, addresses this issue of variability in complex manufacturing environment. We first conducted, in the first part of the manuscript, an in-depth study of “variability”: we approached the notion through its consequences in manufacturing systems, clarified that the variability was about the workflow, introducing the notion of workflow variability and measures that come with it, and identified the main sources of variability through a literature review and real-world examples. We focused in the second part of this manuscript on the integration of workflow variability in production management tools: We showed how integrating the stable consequences of workflow variability can improve WIP projections in complex systems and increase the control on such systems, proposed a new tool (the Concurrent WIP) to better measure the performances of systems subject to high workflow variability, and showed that complex “dependency” mechanisms play a key role in workflow variability yet are not integrated in any model. Finally, the third and last part of the manuscript organized perspectives for variability reduction: based on the work of this manuscript, we showed a framework for variability reduction on the short term, and proposed a direction for medium and long-term research

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Benetti, Heloiza Piassa. "Diretrizes para avaliar a estabilidade do fluxo de valor sob a perspectiva da mentalidade enxuta." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/28931.

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A necessidade de um nível básico de estabilidade nos fluxos de valor vem sendo enfatizada em diversos estudos, como um pré-requisito para a implantação sustentável de princípios e práticas da produção enxuta (PE). Na visão da PE, a estabilidade é multidimensional, devendo incluir todos os elementos de produção que sejam potenciais fontes de variabilidade excessiva. Nesse contexto, esta pesquisa propõe diretrizes para avaliar a estabilidade de um fluxo de valor sob a perspectiva da PE. Além disso, são propostos indicadores para a avaliação de um fluxo de valor de pré-fabricados para a construção civil. Para tanto, a pesquisa foi conduzida nas seguintes etapas: revisão bibliográfica; estudo de caso exploratório e estudo de caso. A pesquisa foi desenvolvida em uma empresa que produz peças de préfabricado de concreto, destinadas à construção civil. No estudo exploratório, foi possível identificar mecanismos para avaliar a estabilidade do fluxo de valor de uma família de produtos, considerando a estabilidade de mão-de-obra, materiais, máquinas e métodos (4M). No estudo de caso, os mecanismos de avaliação foram aplicados, re-interpretando dados já disponíveis na empresa e gerando novos dados, quando necessário. Com base nos resultados dos estudos de campo, bem como na revisão da literatura, foram identificadas cinco etapas para avaliação da estabilidade de um fluxo de valor: (a) desenvolver um mapa do fluxo de valor do estado (MFV) atual; (b) avaliar a estabilidade e a capacidade dos 4M em cada etapa do fluxo de valor; (c) desenvolver melhorias que contribuem para a estabilidade e capacidade; (d) representar as melhorias no MFV do estado futuro; (e) estabelecer um plano de ação para implantar o novo MFV. Vale salientar que, conforme explicitado nas etapas (b) e (c), a avaliação da estabilidade deve necessariamente ser acompanhada pela avaliação da capacidade, na medida em que não basta que os processos sejam estáveis se não atenderem às metas relativas aos clientes internos e externos.
The need for a basic level of stability in the value flow has been emphasized in several studies, as a prerequisite for the implementation of sustainable principles and practices of lean production (LP). In view of the lean production, the stability is multidimensional, and should include all the production elements that are excessive variability potential sources. In this context, this research proposes guidelines to evaluate the stability of a value flow from the perspective of lean production. Besides, indicators are proposed for the evaluation of a value stream of prefabricated materials for the building industry. With this aim, the research was conducted in the following steps: bibliographical review; exploratory study and study case. The collection of field data was developed in the company that produces pieces of concrete precast, destinated to for the building industry. In the exploratory study, it was possible to identify mechanisms to assess the stability of the value flow for one product family, considering the stability of manpower, materials, machines and methods (4M). In the case study, evaluation mechanisms were applied, re-interpreting the data already available in the company and creating new data when necessary. Based on field studies results, and literature review, there are identified five steps to evaluate the stability of a value flow: (a) to develop a value stream mapping of the current state (VSM); (b) to evaluate the 4M stability and capacity in each stage of the value flow; (c) to develop improvements that contribute to the stability and capacity, representing them in the VSM future state; (d) to establish an action plan to deploy the new VSM. It is also important to mention that, as explained in steps (b) and (c) the assessment of stability must necessarily be followed by the capacity assessment, because it is not enough that the processes are stable if they do not follow the internal and external customers’ targets.

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Lopez, Francis. "L'anticorps Ki-67 : étude de sa capacité à révéler les cellules en prolifération et caractérisation de son antigène." Bordeaux 2, 1993. http://www.theses.fr/1993BOR28236.

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Andrade, Gustavo Riente de. "Capacidade e relação fluxo-velocidade em autoestradas e rodovias de pista dupla paulistas." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/18/18144/tde-21062012-103018/.

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Neste trabalho, calibra-se um modelo que descreva a relação fluxo-velocidade em autoestradas e rodovias de pista dupla, considerando as recomendações tecidas pelos autores envolvidos na elaboração do modelo do Highway Capacity Manual - HCM 2010. Para tanto, foi utilizada uma amostra de 788.122 observações, coletadas por 25 estações em quatro rodovias paulistas: SP-348, SP-021, SP-280 e SP 270. A análise dos dados mostrou que, conforme preconizado pelo HCM 2010, existe um intervalo de fluxos no qual a velocidade se mantém constante, o que corresponde à velocidade de fluxo livre. Em seguida, verificou-se que a classificação do HCM 2010, entre autoestradas e rodovias de pista dupla, não se mostra adequada para a amostra estudada, tendo sido indicada a divisão entre rodovias urbanas e rurais. Para esses grupos, foram propostos valores representativos para a capacidade e calibrada a relação fluxo-velocidade. A comparação entre os dois conjuntos de curvas produzidos mostrou que a velocidade média da corrente de tráfego nas rodovias urbanas apresenta uma queda mais precoce e acentuada do que a observada em rodovias rurais. Além disso, os valores estimados para a capacidade C e para a velocidade na capacidade CS para rodovias urbanas são inferiores aos estimados para rodovias rurais. Em contraste com o modelo do HCM 2010, a principal diferença reside em valores significativamente inferiores para BP, o fluxo a partir do qual se nota um declínio da velocidade em função do aumento da densidade da corrente de tráfego. Outro ponto de destaque é que, embora os valores da capacidade sejam parecidos entre o modelo do HCM 2010 e o calibrado, a velocidade na capacidade CS é superior nas rodovias paulistas.
This work presents the calibration of a model describing the speed-flow relationship on freeways and multilane highways in the state of São Paulo, Brazil. The calibrated model follows the recommendations made by the authors involved in the development of the model used by the Highway Capacity Manual HCM 2010. The calibration used a sample of 788,122 observations, collected by 25 stations on four highways at São Paulo state: SP-348, SP-021, SP-280 and 270 SP. The analysis of the data showed that, as advocated by the HCM 2010, there is range of flows in which the average speed of the passenger cars remains constant and equal to the free flow speed. It was also found that the classification scheme used by HCM 2010, comprising freeways and multilane highways, is not adequate for highways in the state of São Paulo. A new classification scheme, which divides highways into urban or rural sections, is proposed. For these classes, representative values for the capacity were found, and the speed-flow relation was calibrated. The comparison between the two sets of curves produced showed that the average speed of the traffic stream on urban highways has an earlier and steeper drop than the observed on rural highways. In addition, the estimated values for the capacity C and for the speed at capacity CS for urban highways are lower compared to the estimated for rural highways. Compared to the model used by the HCM 2010, the main difference lies in the significantly lower values for BP, the traffic flow from which the average speed declines as the density of the traffic stream increases. Another important indication is that, although the capacity values are similar between the model used by the HCM 2010 and the calibrated model, the speed at capacity CS is higher at São Paulo state highways.

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Oliveira, Gabriel Jurado Martins de. "Calibração da relação fluxo-velocidade para autoestradas e rodovias de pista dupla." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18144/tde-10092018-150848/.

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Esta pesquisa apresenta um método de calibração da relação fluxo-velocidade do Highway Capacity Manual, HCM, para autoestradas e rodovias de pista dupla, a partir de recomendações tecidas pelos autores envolvidos na elaboração do manual. Para tanto, foi utilizado uma amostra com mais de 1.700.000 observações, coletadas por 34 sensores de tráfego, localizados em quatros rodovias do Estado de São Paulo: SP-280, SP-348, SP-270 e SP-021. O tratamento do banco de dados foi realizado por meio da filtragem dos dados originais através da aplicação de três critérios, que têm como finalidade remover observações consideradas inadequadas para a calibração do modelo. Os critérios baseiam-se em obter uma corrente de tráfego formada somente por veículos leves, com condições de operação normal e com observações referentes apenas ao regime de fluxo livre. A separação entre os regimes de fluxo livre e congestionado foi realizada por meio da densidade na capacidade. Para tanto, foi proposto um método de estimação da capacidade por meio da análise da variação da velocidade média da corrente em função do fluxo de tráfego. O pressuposto do método parte do conceito de que o colapso da corrente de tráfego é um fenômeno estocástico, caracterizado pela queda abrupta da velocidade média em função do aumento do fluxo de tráfego. O momento em que ocorre mudança abrupta de velocidade é associado ao colapso da corrente de tráfego e consequentemente à capacidade da via. Após a estimação da capacidade, a velocidade na capacidade foi determinada como a média das velocidades associadas ao fluxo na capacidade, enquanto que a densidade na capacidade foi obtida por meio da relação fundamental de tráfego. O método foi aplicado em um conjunto de 18 trechos de rodovias que atingem a capacidade e os resultados foram considerados satisfatórios após a comparação com valores encontrados na literatura. A calibração da relação fluxo-velocidade foi realizada individualmente para cada trecho de rodovia utilizado no estudo. A análise dos resultados mostra que as rodovias rurais apresentam em média valores maiores para velocidade de fluxo livre, capacidade, coeficiente de calibração, velocidade na capacidade e ponto de transição em relação as rodovias urbanas. Alem disso, o ponto de transição, que consiste em um patamar de velocidade de fluxo livre constante, apresenta valores significativamente menores em relação a literatura.
The following research aims to outline a calibration method of the speed-flow relationship presented in the Highway Capacity Manual (HCM). The method is applied on freeways and multilane highways, leveraging the guidelines made by the authors that developed the manual. In order to support the calibration, a sample with more than 1.700.000 observations was used, collected by 34 traffic sensors on four highways at São Paulo state (SP-280, SP-348, SP270, and SP-021). Furthermore, the data treatment and cleaning process aimed to remove observations considered inappropriate from a model calibration perspective by filtering the original data through three main criteria: traffic flow only composed by passenger car, traffic under normal operations condition, and only containing observations which free flow regime applies. The third filtering criteria was applied by splitting free flow and congested regime through the threshold of density at capacity. To this extent, a capacity estimation method was proposed, aiming to analyse the average speed variation in function of the traffic flow. The assumption of the method relies in the concept that the traffic flow breakdown is a stochastic process, characterized by the abrupt drop in the average speed as function of the traffic flow increase. The moment that abrupt drop occurs is related to traffic breakdown and, consequently, to the capacity freeway capacity. Once the capacity was estimated, the speed at capacity was defined as the average of the speed associated with the flow at capacity while the density at capacity was estimated through the fundamental relationship of the traffic flow. The method was applied in 18 delimited highway traffic perimeter that reached their corresponding capacity and the results were considered satisfactory after comparing against values found in the literature. Furthermore, the speed-flow relationships calibration was performed for each of them individually. The results show that rural highways have in average higher free flow speed, capacity, calibration coefficient, speed at capacity and breakpoint than urban highways. Moreover, the breakpoint, which consists a constant free flow speed level, presented significant lower values in comparison to the literature.

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Kolomvos, Georges. "Résolution de grands problèmes stochastiques multi-étapes : Application à un problème de dimensionnement de capacités et de gestion de flux et de stocks." Phd thesis, Ecole Centrale Paris, 2007. http://tel.archives-ouvertes.fr/tel-00275775.

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Dans un monde déterministe, toute donnée d'un problème d'optimisation est censée être connue avec certitude. Dans le monde réel, on est souvent confronté à des cas où certains paramètres sont incertains. La démarche consistant à considérer un seul jeu de paramètres, supposant que ceci représente suffisamment bien la réalité, est vite mise en cause. On considère travailler sur plusieurs périodes temporelles et sur un espace d'incertitude discrétisé, en introduisant ainsi les notions d'arbres de scénarios et des modèles multi-étapes. Les dimensions de ces problèmes augmentent de façon exponentielle avec le nombre de périodes d'étude, rendant les méthodes directes impossibles à appliquer. Le problème qui a motivé ce travail est issu d'une application industrielle réelle et concerne la souscription de contrats dans un marché gazier. Les prix du marché spot, ainsi que la demande clientèle sont considérés incertains, et représentés par un arbre de scénarios. Le modèle qui ressort possède une structure ressemblant à une grande famille de problèmes dynamiques de dimensionnement. A l'issue d'un travail bibliographique, mené particulièrement sur les méthodes de résolution des modèles multi-étapes, la décomposition imbriquée est la méthode qui est retenue. Sur les très grandes instances, même les méthodes de décomposition peuvent s'avérer longues à converger. Cette thèse est consacrée à de nouvelles mises en oeuvre de la décomposition imbriquée, le but étant de pouvoir traiter plus de scénarios en moins de temps. Certains aspects de la méthode sont remis en cause, nous permettant de réduire le nombre d'itérations jusqu'à ce que la convergence soit atteinte. D'autres aspects sont également étudiés dans l'objectif de réduire le temps de calcul passé sur chaque itération séparément. Les démarches proposées sont validées à travers plusieurs séries d'expériences qui mettent en valeur la supériorité de l'approche proposée par rapport à l'approche classique.

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Kolomvos, Georgios. "Résolution de grands problèmes stochastiques multi-étapes : application à un problème de dimensionnement de capacités et de gestion de flux et de stocks." Châtenay-Malabry, Ecole centrale de Paris, 2007. http://www.theses.fr/2007ECAP1044.

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Dans un monde déterministe, toute donnée d'un problème d'optimisation est censée être connue avec certitude. Dans le monde réel, on est souvent confronté à des cas où certains paramètres sont incertains. La démarche consistant à considérer un seul jeu de paramètres est vite mise en cause. On considère travailler sur plusieurs périodes de temps et sur un espace d'incertitude discrétisé, en introduisant ainsi les notions des arbres de scénarios et des modèles multi-étapes. Les dimensions de ces problèmes augmentent de façon exponentielle avec le nombre de périodes d'étude, rendant les méthodes directes de résolution impossibles à appliquer. Le problème qui a motivé ce travail est issu d'une application industrielle réelle et concerne la souscription de contrats dans un marché gazier. Les prix du marché spot, ainsi que la demande clientèle sont connus à travers des scénarios. Le modèle qui ressort possède une structure ressemblant à une grande famille de problèmes dynamiques de dimensionnement. A l'issue d'un travail bibliographique, mené particulièrement sur les méthodes de résolution des modèles multi-étapes, la décomposition imbriquée (DI) est la méthode qui est retenue. Sur les très grandes instances, même les méthodes de décomposition s'avérent longues à converger. Cette thèse est consacrée à de nouvelles mises en œuvre de la DI, le but étant de pouvoir traiter plus de scénarios en moins de temps. Certains aspects de la méthode sont remis en cause, nous permettant de réduire le nombre d'itérations jusqu'à ce que la convergence soit atteinte. D'autres aspects sont également étudiés dans l'objectif de réduire le temps de calcul passé sur chaque itération séparément
In a deterministic setting, data input are considered to be known. However, in real-world applications one may face problems whose parameters are partially or totally uncertain. The approach where one considers a single scenario, which is supposed to represent a mean case, shows quickly its limits. We consider working on a discretized uncertainty space spreading over several time periods; we therefore consider scenario trees and introduce the multistage models associated. Problems dimensions rise exponentially with the number of stages which renders direct solution methods inappropriate. What has motivated our work is an industrial application arising in a gas market, concerning more precisely capacity reservation in the context of a contractual agreement that has to hold over a certain time horizon. Spot prices and clients' demands are considered to be uncertain and are modeled using a scenario tree. The problem structure presents strong similarities with a wide family of problems, where variables are coupling with each other in a very characteristic manner. After a literature survey focusing on (but not limited to) solution methods for multistage models, the Nested Decomposition (ND)method has been chosen. Over very large cases, even decomposition methods show their limits; this concerns in principle convergence times. This work is mostly devoted to the development of new procedures inside the ND method in order to work with larger scenario trees in less time. Other aspects, concerning time reduction over a single iteration are also studied. Comparisons between the classic and the newly presented approaches revealed the superiority of the latter over the former

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Gaüzère, Julie. "Effets de la dispersion du pollen à longue distance sur les capacités d'adaptation de populations de Hêtre commun le long d'un gradient altitudinal." Thesis, Montpellier, SupAgro, 2014. http://www.theses.fr/2014NSAM0028/document.

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La rapidité du changement climatique observé et prédit soulève la question de la vitesse à laquelle les espèces pourront s'adapter au climat futur. Les populations exposées aux changements de conditions environnementales peuvent s'adapter sur place (sans migration) grâce, dans un premier temps, à la réponse plastique des individus, puis, à long terme, par la réponse à la sélection (adaptation génétique). En situation d'environnement variable à la fois dans l'espace et le temps, les flux de gènes peuvent faciliter la diffusion d'allèles bénéfiques entre populations. L'objectif de cette thèse est d'étudier expérimentalement l'interaction entre adaptation et dispersion pollinique à longue distance sur un gradient altitudinal de hêtre commun (Fagus sylvatica). Cette étude a été conduite à partir de trois populations de hêtre sur le versant Nord du Mont-Ventoux (de 900 m à 1400 m d'altitude). Douze traits fonctionnels (phénologiques, physiologiques et morphologiques) potentiellement adaptatifs ont été mesurés sur 60 descendances maternelles issues de ces populations (20 mères/population, 100 individus/mère) et placées en pépinière. Les résultats de cette thèse montrent que (i) les forts taux de pollen immigrant reçus par les populations (m = 56 %) n'empêchent pas l'émergence de patrons de différenciation adaptative, (ii) la sélection érode la variance génétique des traits, (iii) malgré l'existence de variance génétique pour tous les traits, les covariances génétiques entre traits peuvent affecter les taux et directions d'évolution future, et (iv) les flux de pollen contribuent à augmenter la variance génétique totale au sein des populations. Finalement, les populations à moyenne et hautes altitudes pourraient avoir les capacités de s'adapter au climat futur
The rapidity of the climate change observed and predicted raises the issue of how fast species can adapt to future. In face of environmental change, populations can adapt without migrating thanks to their plastic response in a first time, and to their response to selection in the long term (genetic adaptation). In conditions of environment variable both in space and time, gene flow can enhance the spread of beneficial alleles between populations. The objective of this thesis is to experimentally measure the adaptive differentiation and the long-distance pollen dispersal along an elevational gradient of beech populations (Fagus sylvatica). In this study we investigated three beech populations located on the northern side of the Mont-Ventoux (from 900m to 1400m of elevation). Twelve potential adaptive functional traits (phenological, physiological and morphological) have been measured on 60 maternal families collected from these populations (20 mothers/population, 100 offspring/mother) and planted in nursery. The results of this thesis show that that (i) the strong pollen immigrant rate received by the populations (m = 56 %) did not their prevent adaptive differentiation, (ii) the action of natural selection erodes the genetic variance of the traits, (iii) despite significant genetic variance for all the traits, the genetic covariance between traits should affect the rate and direction of evolution in the future, and (iv) gene flow contribute to increase the total genetic variance within the populations. Finally, populations at medium and high elevations may have the potential to adapt to future climate

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Terci, Adriana Oliveira. "Xerostomia em pacientes idosos: relação com o fluxo salivar, proteínas totais, capacidade tampão, pH e medicação em uso." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/23/23139/tde-22042008-115758/.

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O objetivo deste trabalho foi o de investigar as relações entre a queixa de boca seca, em uma população de idosos em bom estado geral, com o fluxo salivar não estimulado, a concentração de proteínas salivares, o pH e a capacidade tampão da saliva, além de considerar as medicações de uso diário consumidas por esses indivíduos. Foram selecionados de forma seqüencial e aleatória 85 pacientes, 13 homens e 72 mulheres, entre os 60 e 82 anos de idade, com média de 68,5 anos. Vinte e um pacientes, todos do sexo feminino, apresentaram queixa de boca seca, quando questionados. Sessenta e sete pacientes utilizavam algum tipo de medicação (79% da casuística). Dezoito indivíduos não consumiam medicamentos, 15 entre os não queixosos de boca seca e apenas três entre os que apresentaram queixa de boca seca. Foram colhidas amostras de saliva de todos os indivíduos, segundo técnica de expectoração não estimulada para recipiente mantido sob refrigeração, durante 15 minutos. Foram feitas, imediatamente após a coleta, o cálculo do fluxo salivar em mililitros por minuto, as medidas do pH, da capacidade tampão e reservados 2ml de saliva em recipiente refrigerado para os procedimentos da pesquisa da concentração proteica salivar. Ainda após a coleta foi aferida a glicemia pós-prandial dos pacientes. Obtivemos os seguintes resultados: Fluxo salivar médio geral de 0,21ml/min; mulheres com queixa 0,16 ml/min; e pacientes sem queixa 0,22ml/min. Capacidade tampão geral de 0,42; mulheres com queixa 0,46; pacientes sem queixa 0,40. Com relação ao pH média geral de 7,22; mulheres com queixa 7,0; pacientes sem queixa 7,22. Concentração de proteínas totais média geral 2,98mg/ml; mulheres com queixa 3,30 mg/ml; pacientes com queixa 2,88 mg/ml. Concluímos que a queixa de xerostomia é mais comum em mulheres e pacientes de maior idade, apresentando correlação positiva com fluxo salivar baixo, maior concentração proteica e maior consumo de medicamentos de uso crônico
The purpose of our trial was to investigate the influence of salivary flow rate, pH, protein content and buffer capacity over the symptom of xerostomia in a population of elderly people exhibiting good health. Eighty-five individuals were randomly selected, 13 men and 72 women, 60 to 82 years, mean 68.5. Twenty-one female patients presented dry mouth complaint when questioned. Seventy-seven patients (79%) were using some type of medication. Eighteen patients were not using drugs, 15 with no dry mouth complaint and three with xerostomia. Unstimulated whole saliva was collected for a period of 15 minutes to a refrigerated recipient. Salivary flow rate, pH and buffer capacity were measured immediately after sampling. Protein concentration was measured later at the lab center in a 2ml sample reserved for this procedure. Additionally, all patients had their glucose level taken. The following results were obtained: mean salivary flow rate of 0,21 ml/min, 0,16 for xerostomia patients and 0,22 for non-xerostomia patients. Mean salivary buffer capacity of 0,42; 0,46 for xerostomia patients and o,40 for non xerostomia patients. Mean pH of 7,22; 7,0 for xerostomia patients and 7,22 for non xerostomia patients. Mean protein concentration of 2,98 mg/ml; 3,30 for xerostomia patients and 2,88 for non xerostomia patients. We concluded that xerostomia is more prevalent in women and older patients, presenting positive correlation with low salivary flow rate, greater protein concentration and multiple drug use.

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Marques, Tanyse Bahia Carvalho. "Avaliação do pico de fluxo de tosse e capacidade vital forçada em pacientes com distrofia muscular ou amiotrofia espinhal submetidos a treinamento de empilhamento de ar." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/5/5138/tde-20122012-123112/.

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Introdução: As complicações respiratórias, somadas a baixos volumes pulmonares e tosse ineficiente, decorrentes da fraqueza da musculatura respiratória nas doenças neuromusculares (DNM), são as principais causas de morbidade e mortalidade. Objetivo: Verificar os efeitos do treinamento de empilhamento de ar na função respiratória de pacientes com DNM. Métodos: Estudo prospectivo em 21 pacientes com DNM, idade entre 7 e 23 anos. Todos foram submetidos a avaliações respiratórias a cada 4 e 6 meses. Realizou-se espirometria e medida do pico de fluxo de tosse não assistido e assistido (PFTNA e PFTASS) com insuflações e empilhamento de ar com ressuscitador manual. Os pacientes e cuidadores foram treinados e orientados a realizar o treinamento das manobras de empilhamento de ar diariamente no domicílio. A análise estatística utilizou o pacote estatístico como médias ± desvios-padrão, foram submetidas ao teste de normalidade de D\'Agostino-Pearson. Utilizou-se ANOVA para medidas repetidas, seguidas do teste Post Hoc de Tukey. O pico de fluxo expiratório (PFE) não exibiu distribuição normal e, por isso, foi submetido ao teste de Friedman seguido do teste Post Hoc de Dunn. Os coeficientes de correlação de Pearson foram calculados e nível de significância estabelecido foi p < 0,05. Resultados: Houve aumento na estatura média dos pacientes de 2,5 cm (p < 0,0001). A média da capacidade de insuflação máxima (CIM) foi maior que a capacidade vital forçada (CVF) basal em todas as avaliações (p < 0,0001). Houve aumento na média da CVF e CIM (p < 0,01), PFTNA (p < 0,05) e no PFTASS após período de treinamento nos pacientes com escoliose não estruturada ou ausente. Conclusão: O treinamento domiciliar com insuflações e empilhamento de ar deve ser enfatizado nas DNM, pois aumenta o PFT. Tal treinamento aumenta a CVF basal e o PFTNA nos pacientes sem deformidades torácicas.
Introduction: Respiratory complications, low lung volumes and inefficient cough, resulting from weakness of respiratory muscles are the major causes of morbidity and mortality in neuromuscular patients (NMD). Objective: To assess the effects of air stacking training on lung function in patients with NMD. Methods: Prospective study in 21 patients with NMD aged 7 to 23 years. Al patients underwent respiratory evaluations every 4 to 6 months. Was performed spirometry and measurement of unassisted peak cough flow (UPCF) and assisted peak cough flow (APCF) with insufflations and air stacking with manual resuscitator. The patients and caregivers were trained and were prescribed lung insufflations by air stacking three times each day at home. The statistical analysis used the statistical package GraphPad Prism 5.0 for Windows. Spirometric variables were expressed as means ± standard deviations, were subject to normality test D\'Agostino-Pearson. We used ANOVA for repeated measures followed by post hoc Tukey test. The peak expiratory flow (PEF) did not exhibit normal distribution and therefore was subjected to the Friedman test followed by Dunn´s post hoc test. The Pearson correlation coefficients were calculated and significance level was set at p < 0.05. Results: There was in increase in the average height of 2.5 cm, of the patients (p < 0.0001). The mean maximum insufflation capacity (MIC) was greater than forced vital capacity (FVC) baseline for all evaluations (p < 0.0001). There was increase in mean FVC and MIC (p < 0.001), UPCF (p < 0.05) and APCF (p < 0.01) after air stacking training period in patients without scoliosis or unstructured. Conclusion: The air stacking training home should be emphasized in NMD. This training increases the FVC and UPCF in patients without scoliosis or unstructured.

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Pozza, Fernando. "Análise térmica e energética de uma edificação residencial climatizada com sistema de Fluxo de Refrigerante Variável -VRF Fernando Pozza." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/34759.

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O trabalho apresenta uma análise térmica e energética de uma edificação localizada na zona bioclimática 1, que compreende as cidades mais frias do Brasil. A análise foi desenvolvida com o auxílio do programa de simulação dinâmica de edificações EnergyPlus em que foi determinado o consumo anual de energia elétrica de toda a edificação existente, bem como o consumo do sistema HVAC (Aquecimento, Ventilação e Ar Condicionado) do tipo split com ciclo reverso. O sistema HVAC existente representa 42% do consumo total de energia elétrica da edificação sendo que o aquecimento totaliza 89% do consumo do sistema HVAC. A avaliação do conforto térmico dos ambientes climatizados da edificação foi realizada tendo como referência as zonas de conforto de inverno e de verão definidas pela ASHRAE Standard 55-2004. Os ambientes apresentaram um percentual de 7,6 % a 33% das horas de operação do sistema HVAC fora da zona de conforto térmico de inverno da ASHRAE, considerando somente a temperatura operativa. A partir dos resultados da simulação da edificação existente foram propostas modificações na envoltória e o uso de um sistema de ar condicionado com tecnologia VRF (fluxo de refrigerante variável) a fim de reduzir o consumo de energia pelo HVAC e o número de horas desconfortáveis. A utilização de vidros duplos de maior transmissividade, superfícies com cores de maior absortividade solar, lã de vidro nas paredes externas e internas duplas e placas de EPS (Poliestireno Expandido) no piso da edificação, apresentaram ótimos resultados, reduzindo o consumo total de energia elétrica em 18,2% e o consumo do sistema HVAC passou a representar apenas 29,6% do total de energia da edificação. Após o aprimoramento da edificação foram selecionadas, a partir de catálogos de fabricantes, as máquinas com tecnologia VRF que atendessem a máxima carga térmica entre os dias de projeto ou arquivo climático sob determinadas condições. Os resultados obtidos com o sistema VRF apresentaram uma redução de 32,8% sobre o consumo de energia do sistema de HVAC e de 9,3 % sobre o consumo total de energia elétrica da edificação quando comparado com um ar condicionado tradicional do tipo split. Com a melhoria na envoltória e o uso da tecnologia VRF para climatização o percentual de horas fora das zonas de conforto da ASHRAE foram menores que os 4% estabelecido pela norma, quando considerado a temperatura operativa. O sistema VRF foi simulado adaptando o módulo de simulação de serpentinas de expansão direta com compressores de velocidade variável, do EnergyPlus, para quatro faixas de capacidades distintas do compressor (60%, 80%, 100% e 120%) e para cada faixa foram inseridas as correlações de desempenho da capacidade e potência elétrica de aquecimento e refrigeração para diferentes condições de operação. Nas simulações foram considerados a perda de desempenho e o consumo elétrico para a operação de degelo com ciclo reverso para temperaturas externas inferiores a 7º C. As simulações com o sistema VRF acoplado a edificação comprovam a capacidade de economizar energia elétrica, além de apresentar o menor custo especifico da energia para aquecimento em relação aos sistemas radiantes.
This dissertation presents the thermal and energetic analysis of a building located in the bioclimatic zone 01, which comprises the coldness regions of Brazil. The analysis was developed using the software for dynamic simulation of buildings called EnergyPlus, where was determined the annual consumption of electricity throughout the existing building as well as the consumption with lighting, electrical equipments and the HVAC system. The existing HVAC system represents 42% of total consumption and the heating corresponds to 89% of the total energy consumption of the HVAC system. The evaluation of thermal comfort zones of building were conducted with reference to the comfort zones of winter and summer from the ASHRAE Standard 55-2004. The thermal zones presented a percentage in the range of 7.6% to 33% of occupation hours outside the boundaries of ASHRAE thermal comfort zone (winter) evaluating the operating temperature. Based on simulation results of the existing building, changes were proposed in the envelope and in the use of a heat pump air conditioning system with VRF technology (variable refrigerant flow) to reduce the energy consumption of the HVAC and the number of hours outside the comfort zone. The use of double layers glasses with high transmissivity and surfaces colored with high solar absorption, wool glass in the external and double internal walls and EPS sheets on the building floor, presented excellent results. The modification of the envelope decreased 18.2 % in the total consumption of electricity and the HVAC system represents only 29.6% of the total energy of the building. After the building improvement was selected from catalogs of manufacturers, machines with VRF technology that could meet the maximum heat load between design days or weather file. The results obtained with the VRF system showed a 32.8% reduction on energy consumption of HVAC system and 9.3% about the total consumption of electricity of the building compared to a traditional heat pump air conditioning system with single speed compressor. With the improvement in the envelope and the use of VRF system the percentage of hours outside the ASHRAE comfort zones were lower than the 4% target set by the standard. The VRF system was modeled from model: Multi-Speed Electric DX Air Coil, of the EnergyPlus, for four different capacities of the compressor (60, 80, 100 and 120%) and for each capacity range were included the performance correlation of heating and cooling capacity, the correlations of electrical power heating and cooling for different condition of operate and correlation of the fraction of part load operation for each machine selected. As the study was conducted to the cooler regions of Brazil, defrost was considered in the simulation with reverse cycle for operating temperatures below 7°C. The heating energy with heat pump VRF presents lower specific cost compared to radiant systems like radiant floor and radiators.

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Chvíla, Ladislav. "Vlastnosti fraktálních kapacitorů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2012. http://www.nusl.cz/ntk/nusl-219892.

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This work is focused on computer simulations of fractal capacitors. The geometry of capacitors and its influence is investigated. Simulations are realized in programs Matlab, SolidWorks and Comsol Multiphysics. There are also several specific examples of different geometrics of capacitors their comparisons and assessment.

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Baldi, Murilo Melhado. "Proposta de um modelo de programação estruturado a partir das particularidades do fluxo de produção de um sistema de manufatura celular." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/18/18156/tde-23042018-094809/.

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A proposta de um procedimento de programação da produção, estruturado a partir das particularidades do fluxo de produção de um sistema de manufatura celular, descrita neste trabalho, é resultado do processo de investigação da relação do uso de ferramentas computacionais, especialistas em programação da produção, envolvendo práticas de controle de estoque no abastecimento de um sistema de manufatura celular. Deste modo, o conteúdo deste trabalho trata das principais restrições inerentes a relação entre os diferentes parâmetros e variáveis do processo de fabricação deste tipo de sistema, os quais interferem diretamente na eficácia e eficiência de um sistema de programação da produção, além de enfatizar os resultados efetivos que podem ser alcançados com o uso de um software APS, assim como uma lógica de programação, com ênfase na minimização do Lead Time Offsetting. Neste contexto, além do resultado efetivo que este trabalho demonstra, a partir do uso de um sistema de programação da produção em um ambiente de manufatura celular, há, inerentemente, o destaque à relevância do tema de pesquisa, estudado na literatura, devido ao crescente aumento da complexidade dos sistemas produtivos e, consequentemente, da dificuldade de análises mais precisas do impacto que as variáveis de fluxo, como por exemplo, tempos de abastecimento e movimentação, tempos de setup e os respectivos roteiros de fabricação, podem causar no desempenho dos processos no chão de fábrica. Quanto ao método de pesquisa o estudo aborda o tema, quanto à aplicação de um modelo de programação da produção estruturado, com base no escopo da proposta, através de um estudo de caso de uma empresa fornecedora de componentes do setor de automotivo, envolvendo pesquisa de campo com acesso a documentos do processo de fabricação e da estrutura de materiais do mix de produtos relacionados, além do contato direto com os atores do processo de fabricação a partir de reuniões periódicas durante o processo de concepção do procedimento. A partir da construção do modelo de programação, cenários são gerados de modo a comparar a performance dos mesmos em um ambiente produtivo real, sendo realizadas alterações de variáveis no fluxo produtivo, a fim de obter resultados interessantes e satisfatórios, utilizando-se de parâmetros como tamanho de lote e makespan como indicadores de performance.
The proposal of a production programming procedure, built from the particularities of a cellular manufacturing system\'s production flow, described in this work, is the result of a investigation process about the relation of using computational tools, specialized in production programming, involving practices of inventory control in a supply system of a manufacturing cell. Thus, the content of this work deals with the main constraints inherent in the relationship between different parameters and variables of the manufacturing process, regarding this type of production system, that directly interferes in the efficiency of a production scheduling system, emphasizing the effective results that can be achieved through the use of an APS software and programming logic, with emphasis on minimizing Lead Time Offsett. Thereby, in addition to the effective result that this work demonstrates about the use of a production programming system, in a cellular manufacturing environment, we should also emphasize the topic reserchead, and studied, in this work due to the increasing complexity of manufacturing systems and environments as well as the difficulty of more precise analyzes regarding the impact of production flow variables, such as supply and movement times, setup times and the variability offered by manufacturing routes, which can cause underperformance of production processes in a factory. About the research method, this study approaches the subject, regarding the application of a programming model, based on the scope of the initial proposal, through a case study of a company that supplies automotive componentes, in the brazilian automobile sector. This study encompasses field research with access to documents of the manufacturing process as well as the bill of materials of related products, also, direct contact with the actors of the manufacturing process through periodic meetings during the procedure design process. Regarding the results achieved by this work, it is important to highlight the creation of different cenarios and comparisons that were made, regarding the use of different parameters and variables, such as makespan and lot sizing, so that the optimal experience could be achived, through the use of a customized programming model developed, exclusively, for this research.

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Gaultier, Valérie. "Contribution à l'etude des échanges de phosphate à l'interface eau-sédiment en milieu fluvial : evaluation des flux. : Mesure des capacités de relargage et d'adsorption des sédiments : Applications aux fleuves Seine et Charente." Lyon, INSA, 1994. http://www.theses.fr/1994ISAL0091.

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Cette recherche vise à identifier les formes d'accumulation du phosphate dans les sédiments, leur évolution ainsi que leur transfert au sein du sédiment et à l'interface eau-sédiment. Dans le phénomène d'eutrophisation des fleuves, les processus d'échanges du phosphate à l'interface eau-sédiment jouent un rôle non négligeable. Le stock de phosphate des sédiments peut être en effet mis en solution dans des conditions physico-chimiques et biologiques particulières et rejoindre le phosphate apporté par le bassin versant. Les mécanismes contrôlant la distribution du phosphate entre les phases dissoute et particulaire sont l'adsorption, la désorption, la précipitation la dissolution, l'assimilation biologique la minéralisation de la matière organique. Les échanges de phosphate à l'interface eau-sédiment sont dépendants de la diffusion moléculaire, de la bioturbation, de l'advection, de la remise en suspension et de la sédimentation. La diagénèse précoce dans le sédiment fait référence à l'ensemble de ces mécanismes. La spéciation chimique des formes du phosphate selon la méthode de Williams et Jacquet (1976) fait apparaître que plus de 50 % et plus de 40 % du phosphate total des sédiments correspond en partie aux phosphates liés aux hydroxydes de fer, respectivement pour les stations d'étude de la Seine et de la Charente. Les flux diffusifs à l'interface eau-sédiment, calculés à partir des gradients de concentration en orthophosphates obtenus à l'aide de plaques à diffusion, sont dirigés de l'eau interstitielle des sédiments vers la colonne d'eau. Ces flux diffusifs sont en moyenne inférieurs à 1 mg. M-2. H-1 et n'engendrent pas d'augmentation significative dés concentrations en orthophosphates dans la colonne d'eau. Les flux benthiques à l'interface eau-sédiment, estimés in situ à l'aide de chambres benthiques, prennent en compte les phénomènes d'adsorption, de désorption, de bioturbation et d'advection, contrairement aux flux diffusifs. Ainsi, aux stations d'étude de la Seine, les flux benthiques sont de l'ordre de 10 mg. M-2. H-l et sont supérieurs aux flux diffusifs. Aux stations d'étude de la Charente, aucun flux benthique n'est détecté. L'apport de phosphate particulaire au sédiment de surface (compris entre 3 et 103 mg. M-2. H-1) est toujours su~rieur à l'exportation de phosphate dissous du sédiment par diffusion. Ceci peut provenir du fait que les flux de sédimentation mesurés à l'aide de pièges à sédiment sont surestimés en raison de la resuspension. Des expérimentations de remise en suspension en réacteur ont permis d'estimer les capacités des particules de sédiment à relarguer ou à adsorber le phosphate. Le relargage peut être à l'origine d'une augmentation des concentrations en orthophosphates dans la phase dissoute de l'ordre de 0. 5 mg. I- 1. Après adsorption, la charge interne initiale en phosphate total des particules de sédiment peut augmenter de 20 à 100 %. Ces quantités de phosphate relarguées et adsorbées non négligeables démontrent que la remise en suspension. Constitue une voie importante de transfert du phosphate entre les phases particulaire et dissoute
This research aims to identify the forms of phosphate accumulation in sediments, their evolution and their transfer within the sediment and at the sediment-water interface. In the eutrophication of rivers, phosphate exchanges at the sediment-water interface play an important role. In specific physical , chemical and biological conditions, the internal phosphate loading of the sediment can return. Into solution and rejoin the phosphate brought by the watersheds. The mechanisms controlling the repartition of phosphate between the dissolved and the particular phase are adsorption desorption, precipitation dissolution an~ biological assimilation mineralisation of organic matter. The exchanges of phosphate at the sediment-water Interface are dependent of diffusion, bioturbation, advection, resuspension and sedimentation. Early diagenesis refers to ail these processes. The fractionation of the different forms of phosphate, according to the scheme of Williams and Jacquet (1976), shows that more than 50 % and 40 % of total phosphate correspond to ferric hydroxides bound phosphate, respective! y at the stations of Seine and Charente rivers. Diffusion fluxes at the sediment-water interface, calculated from the orthophosphate's concentration gradients obtained with diffusion samplers, are directed from the interstitial water toward the water column. The diffusion fluxes are, in average, lower than 1 mg. M-2. H-l, and do not create significant increase of the concentrations of ortbophosphates in the water column. The benthic fluxes at the sediment-water interface, evaluated in situ with benthic chambers, take into account adsorption, desorption, bioturbation and advection, unlike the diffusion fluxes. So, at the station of river Seine, benthic fluxes are around 10 mg. M-2. H-l and are higher than diffusion fluxes. At the stations of river Charente, no flux is detected. The particular phosphate brought to surficial sediment (between 3 and 103 mg. M-2. H-l) is al ways higher than the export of dissolved phosphate from the sediment by diffusion. This can be attributed to the fact that the sedimentation fluxes are overestimated. Owing LO resuspension. . Experimentatio n s of resuspension in reactor, allowed to estimate the phosphate re lease and adsorption capacity of the sediment. The release can be at the origin of an increase of phosphate concentrations in the dissolved phase of 0. 5 mg. L- 1. After adsorption, the total phosphate initial internal loading of the sediment particles can increase from 20 to lOO %. The released and adsorbed phosphate quantities demonstrate that resuspension constitutes an important way of phosphate transfer between the particular and the dissolved phases

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Rocha, Ednardo Pereira da. "Análise Trifásica de Sistemas de Distribuição com Modelos de Turbinas Eólicas Tipo IV." Universidade Federal Rural do Semi-Árido, 2015. http://bdtd.ufersa.edu.br:80/tede/handle/tede/533.

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Fundação de Apoio a Pesquisa do Estado do Rio Grande do Norte
The connection of wind generators might cause significant influences in the profile voltages, voltage unbalance, loading and the electrical losses in radial power distribution systems. This fact requires a specific study, called Hosting Capacity, which aims to analyze the maximum limit of the power increase on the network that makes the performance of the system acceptable to the established quality limits. This work shows an IEEE radial distribution system behavior, composed of 13 bus, in steady state, when a synchronous wind machine is engaged on the bus 680 in two ways: directly connected to the network and connected through the frequency converter. For each type of connection the power factor was varied from 0.9 capacitive to inductive 0.9. The parameters analyzed in connection bar were the degree of voltage unbalance, the losses in the system and the profile of voltages on the bus 680 for each case . The simulations were performed using the program Distribution Network Analysis with Generation Aeolian-Electric - ANAREDGEE, which was developed and validated with own results of the IEEE. It was found that there was a reduction in the degree of unbalance for all simulated situations, when compared to the original value of the system status, not exceeded the limits determined by imbalances entities NEMA, ANSI, IEEE and ANEEL. Regarding the profile of voltages in the various system buses, there was a slight decrease in some situations. In the original system, the voltage level of the phase B in the bus 680 exceeded the 5% voltage given by ANEEL, with a value of 1.0529 p.u. With the machine connected directly, there was an increase of this value in all simulations with different power factor, while the connection through frequency converter might causa a reduction of the phase B voltage levels to below 1.05 pu in situations where the power factors were equal to 0.9 capacitive and unitary. The system losses were reduced in all cases, but showed lower values when the synchronous machine was integrated into the system by frequency convertor. It was also observed a significant reduction in the degree of system imbalance after connecting the synchronous machine, this reduction, in most cases, occurred in proportion to the increase in power injected into the connection bar
A conexão de geradores eólio-elétricos pode causar influências significativas no perfil de tensões, desequilíbrio de tensão, no carregamento e nas perdas elétricas em sistemas de distribuição de energia radiais. Este fato requer um estudo específico, denominado Hosting Capacity, que tem por finalidade analisar o limite máximo do incremento de potência na rede que torna a performance do sistema aceitável para os limites de qualidade estabelecidos. Este trabalho demonstra o comportamento do sistema de distribuição radial do IEEE, composto de 13 barras, em regime permanente, quando uma máquina eólica síncrona é acoplada na barra com o maior nível de tensão do sistema, de duas formas distintas: diretamente conectada à rede e conectada por meio de conversor de frequência. Para cada tipo de conexão o fator de potência foi variado de 0.9 capacitivo a 0.9 indutivo. Os parâmetros analisados na barra de conexão foram o grau de desequilíbrio de tensão, as perdas no sistema e o perfil das tensões. As simulações foram realizadas através do programa Análise de Redes de Distribuição com Geração Eólio-Elétrica - ANAREDGEE, que foi desenvolvido e validado com resultados próprios do IEEE. Verificou-se que houve uma redução no grau d e desequilíbrio para todas as situações simuladas, quando comparadas ao valor da situação original do sistema, não superado os limites de desequilíbrios determinados por entidades como NEMA, ANSI, IEEE e ANEEL. Com relação ao perfil das tensões nas diversas barras do sistema, houve uma ligeira diminuição em algumas situações. No sistema original, o valor de tensão na fase B da barra 680 superava os 5% de sobretensão determinado pela ANEEL, apresentando um valor de 1,0529 p.u. Com a máquina diretamente conectada houve um aumento deste valor em todas as simulações com diferentes fatores de potência, enquanto que a conexão por meio de conversor de frequência possibilitou uma diminuição dos níveis de tensão da fase B para valores abaixo de 1,05 p.u. nas situações em que os fatores de potência eram iguais a 0.9 capacitivo e unitário. As perdas no sistema foram reduzidas em todos os casos, entretanto apresentaram menores valores quando a máquina síncrona era integrada ao sistema por meio de conversor de frequência. Foi observado também uma redução considerável do grau de desequilíbrio do sistema após a conexão da máquina síncrona, esta redução, na maioria dos casos, se deu de forma proporcional ao aumento da potência injetada na barra de conexão

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Durollet, Marie. "Régulation de la fonction cardio-respiratoire au cours du cycle de vie de Nothobranchius furzeri : rôle de la température." Thesis, La Rochelle, 2015. http://www.theses.fr/2015LAROS037/document.

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Le système cardio-respiratoire joue un rôle prépondérant au sein d’un organisme, en permettant notamment l’apport et la distribution du dioxygène et des nutriments à l’ensemble des cellules. Mieux comprendre les modifications du système cardio-respiratoire au cours de la vie est donc un élément central dans l’évaluation de la capacité de l’organisme à répondre à ses différents besoins énergétiques, ainsi que dans la compréhension du phénomène de mortalité naturelle liée à la sénescence. Cette étude a été réalisée sur un vertébré à durée de vie extrêmement courte (~6 mois), le poisson Nothobranchius furzeri. La température, en plus d’être considérée comme l’un des principaux facteurs environnementaux susceptibles d’influencer la physiologie des téléostéens, est connue pour son effet régulateur sur la longévité. Ainsi, les individus étaient acclimatés à deux températures, 26 °C considérée comme la température optimale chez cette espèce, et une température réduite de 22 °C. Au niveau individuel, les réponses biologiques ont été explorées au travers des performances physiologiques comme mesure indirecte de la fitness : la capacité métabolique aérobie (AS), la croissance, les performances de reproduction, de locomotion et de digestion. A l’échelle sub-individuelle, les mécanismes de régulation de la fonction cardiaque ont été examinés via une étude morpho-fonctionnelle des cardiomyocytes. Les résultats mettent en évidence la présence au cours de la vie de deux phases bien distinctes délimitées par un âge optimal : (1) une première phase d’élévation de l’AS des stades juvénile à adulte ; suivie (2) d’une seconde phase, synonyme de déclin de l’AS, des indicateurs cardiaques et des niveaux d’activités ciblés, associés probablement à l’entrée en sénescence. Une réduction de température accroit la longévité, et retarde les effets néfastes du vieillissement sur l’AS, et les performances cardiaques. Cette étude contribuera à établir une vision globale des effets du vieillissement sur la fonction cardio-respiratoire et à mieux comprendre les mécanismes mis en jeu lors d’un allongement de la longévité par une réduction de la température
Cardio-respiratory system plays a key role in an organism by delivering oxygen and nutrients towards the cells. Exploring its age-dependant changes is therefore a corner stone for assessing the organism capacity to meet its energetic needs along its life cycle, and for the understanding of mechanisms involved in the mortality due to aging process. This study was realized in a vertebrate with an extremely short lifespan (~6 months), the fish Nothobranchius furzeri. Temperature is an external factor that regulates longevity. Here, fish were acclimatized at two temperatures, 26 °C considered as the optimal temperature for this species, and 22 °C. Biological responses of fish were evaluated at individual level through the assessment of aerobic metabolic scope (AS), growth, reproduction, locomotion and digestion, which are considered to be relevant indirect measurement of fitness. Furthermore, mechanisms involved in the cardiac function regulation were explored through a morpho-functional study of cardiomyocytes. Along the individual life cycle, two phases were emphasized: 1) the first corresponds to AS elevation from the juvenile to the adult stages, following by 2) a second phase reflecting the entrance in the senescent stage, characterized by the decline in AS, cardiac performances and in activity level. A temperature reduction increases the individual longevity and slows-down deleterious effect of aging on both AS and cardiac function. This study will contribute to provide a global vision of senescent effects on cardio-respiratory system, and a better understanding of the mechanisms involved in temperature-dependent increase in longevity

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Carvalho, Ivo Miguel Oliveira de. "Avaliação da função pulmonar em jovens adultos em diferentes posicionamentos." Bachelor's thesis, [s.n.], 2018. http://hdl.handle.net/10284/7090.

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Projeto de Graduação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciado em Fisioterapia
Objetivo: Avaliar e comparar a função pulmonar em jovens adultos, fumadores, não fumadores, praticantes e não praticantes de atividade física em diferentes posicionamentos. Metodologia: Estudo observacional transversal em 80 jovens adultos (22,00 ± 2,8 anos), tendo sido avaliada a Capacidade Vital Forçada (CVF), Volume Expiratório Forçada no primeiro segundo (VEF1), Pico de Fluxo Expiratório (PFE) através da espirometria em diferentes posicionamentos. Utilizou-se ainda o IPAQ- Questionário Internacional de Atividade Física – versão curta, para avaliar a intensidade de treino dos participantes (vigorosa/moderada). Resultados: Verificaram-se diferenças significativas em termos de volumes respiratórios nos diferentes posicionamentos, em todas as variáveis em estudo, bem como diferenças entre os grupos. Conclusão: Os posicionamentos, os hábitos tabágicos e a prática atividade física parecem influenciar a função pulmonar em jovens adultos.
Purpose: Evaluate and compare the respiratory capacity in young people, smokers, non-smokers, practitioners and non-practitioners of physical activity in different positions. Methodology: Observational cross-sectional study in 80 young adults (22.00 ± 2.8 years), with Forced Vital Capacity (FVC), Forced Expiratory Volume in the first second (FEV1), Expiratory Flow Peak (PEF) by spirometry in different positions. The IPAQ - International Questionnaire on Physical Activity - short version. It was used to evaluate the intensity of training of the participants (vigorous / moderate). Results: There were significant differences in respiratory volumes in the different positions, in all study variables, as well as differences between groups. Conclusion: Positions, smoking habits and physical activity practice influence the respiratory capacity.
N/A

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Trad, Abdelbasset. "Déploiement à grande échelle de la voix sur IP dans des environnements hétérogènes." Phd thesis, Nice, 2006. http://tel.archives-ouvertes.fr/tel-00406513.

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Dans cette thèse, nous nous intéressons au déploiement à grande échelle de la Voix sur IP (VoIP) dans des environnements Internet hétérogènes. Après une description des mécanismes de codage et de transmission de la voix sur l'Internet, nous étudions dans une première partie de la thèse, les limites de performance dans le cas d'une transmission d'un grand nombre de flux de voix sur IP entre deux passerelles téléphoniques. Nous discutons le besoin d'utilisation de mécanismes de contrôle de congestion pour le trafic de voix sur IP qui est en croissance continue sur l'Internet. Nous proposons un nouveau schéma de contrôle de congestion de la voix sur IP. Ce schéma combine le multiplexage de flux RTP et le mécanisme de contrôle TCP-amical (TCP-friendly) afin d'améliorer l'efficacité et la performance de la transmission des flux de voix sur IP et de garantir l'équité avec les autres types de trafic coexistant sur l'Internet. La deuxième partie de la thèse est consacrée à l'étude de la transmission de la voix dans des environnements de réseaux locaux sans fil IEEE 802.11e. Nous développons un modèle analytique permettant d'évaluer la capacité d'un réseau 802.11e en nombre de communications de voix sur IP en fonction des paramètres de l'application (codage audio utilisé) ainsi que des paramètres relatifs aux canal de transmission sans fil. Ce modèle peut être utilisé pour ajuster ces paramètres afin d'augmenter la capacité du réseau sans fil tout en considérant les contraintes strictes des communications interactives de la voix sur IP. Dans la dernière partie de la thèse, nous étudions le cas de la transmission de la voix sur IP dans des environnements Internet hétérogènes (filaires/sans fil) constitués en partie par des liens d'accès sans fil. Nous proposons une architecture basée sur une passerelle de voix sur IP placée au bord du réseau sans fil. Cette passerelle est utilisée pour adapter les flux de voix aux caractéristiques du réseau sans fil. Le mécanisme d'adaptation proposé estime dynamiquement l'état de congestion du canal sans fil et permet la différentiation entre les pertes de paquets causées par la congestion et celles dûes aux erreurs de transmission sur le canal sans fil. L'adaptation appropriée est alors appliquée. Le mécanisme d'adaptation proposé, ne nécessite pas de modifications du protocole de contrôle d'accès au canal sans fil (MAC), ce qui facilite son déploiement sur l'infrastructure réseau existante.

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Montsutsumi, Márcio Masatoshi [UNESP]. "Otimização simultânea da reconfiguração e da alocação de bancos de capacitores em sistema de distribuição radiais utilizando uma estratégia multipartida." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/148620.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
O objetivo deste trabalho é desenvolver uma ferramenta para otimização de sistema de distribuição que utiliza uma meta-heurística baseada em uma metodologia multipartida para reconfigurar e alocar bancos de capacitores fixos e chaveados para obter a topologia radial que apresente o menor custo de operação. Para encontrar topologias iniciais radiais na reconfiguração do sistema foi aplicado o algoritmo de Prim e com a solução obtida realizouse um processo de melhoria denominado busca pela vizinhança. O sistema melhorado é submetido a um algoritmo de alocação de bancos de capacitores mostrando que é possível obter uma topologia radial que apresenta mais econômico custo de operação. Como proposta da metodologia multipartida o procedimento é repetido até um critério de parada definido, assim são geradas diversas soluções e a melhor delas será a solução do problema. Todos os programas foram escritos em linguagem C++, e aplicado em sistemas de 69 barras, 84 barras e 135 barras.
The purpose of this research is to develop a tool for optimization in power system distribution that uses meta-heuristic based on a multi-start methodology to reconfigure and allocate fixed and switched capacitor banks to obtain the radial topology that presents the lowest operating cost. To find initial radial topologies for system reconfiguration, the Prim algorithm was applied and to the current solution an improvement process called “neighborhood search” was performed. The improved system is subjected to a capacitor allocation algorithm showing that it is possible to get a radial topology that presents more economic cost of operation. As a proposal of the multi-start methodology, the procedure is repeated until a desired stop criterion, then several solutions are generated and the best one can be the solution of the problem. All programs were written in C ++ and applied to systems of 69 nodes, 84 nodes and 135 nodes.
CNPq: 130695/2015-7

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Montsutsumi, Márcio Masatoshi. "Otimização simultânea da reconfiguração e da alocação de bancos de capacitores em sistema de distribuição radiais utilizando uma estratégia multipartida /." Ilha Solteira, 2017. http://hdl.handle.net/11449/148620.

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Orientador: Rubén Augusto Romero Lázaro
Resumo: The purpose of this research is to develop a tool for optimization in power system distribution that uses meta-heuristic based on a multi-start methodology to reconfigure and allocate fixed and switched capacitor banks to obtain the radial topology that presents the lowest operating cost. To find initial radial topologies for system reconfiguration, the Prim algorithm was applied and to the current solution an improvement process called “neighborhood search” was performed. The improved system is subjected to a capacitor allocation algorithm showing that it is possible to get a radial topology that presents more economic cost of operation. As a proposal of the multi-start methodology, the procedure is repeated until a desired stop criterion, then several solutions are generated and the best one can be the solution of the problem. All programs were written in C ++ and applied to systems of 69 nodes, 84 nodes and 135 nodes.
Mestre

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Pimentel, Filho Max Chianca. "Uso de t?cnicas de otimiza??o baseadas em derivadas como suporte do planejamento operacional de redes de distribui??o de energia el?trica." Universidade Federal do Rio Grande do Norte, 2005. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15126.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
The usual programs for load flow calculation were in general developped aiming the simulation of electric energy transmission, subtransmission and distribution systems. However, the mathematical methods and algorithms used by the formulations were based, in majority, just on the characteristics of the transmittion systems, which were the main concern focus of engineers and researchers. Though, the physical characteristics of these systems are quite different from the distribution ones. In the transmission systems, the voltage levels are high and the lines are generally very long. These aspects contribute the capacitive and inductive effects that appear in the system to have a considerable influence in the values of the interest quantities, reason why they should be taken into consideration. Still in the transmission systems, the loads have a macro nature, as for example, cities, neiborhoods, or big industries. These loads are, generally, practically balanced, what reduces the necessity of utilization of three-phase methodology for the load flow calculation. Distribution systems, on the other hand, present different characteristics: the voltage levels are small in comparison to the transmission ones. This almost annul the capacitive effects of the lines. The loads are, in this case, transformers, in whose secondaries are connected small consumers, in a sort of times, mono-phase ones, so that the probability of finding an unbalanced circuit is high. This way, the utilization of three-phase methodologies assumes an important dimension. Besides, equipments like voltage regulators, that use simultaneously the concepts of phase and line voltage in their functioning, need a three-phase methodology, in order to allow the simulation of their real behavior. For the exposed reasons, initially was developped, in the scope of this work, a method for three-phase load flow calculation in order to simulate the steady-state behaviour of distribution systems. Aiming to achieve this goal, the Power Summation Algorithm was used, as a base for developing the three phase method. This algorithm was already widely tested and approved by researchers and engineers in the simulation of radial electric energy distribution systems, mainly for single-phase representation. By our formulation, lines are modeled in three-phase circuits, considering the magnetic coupling between the phases; but the earth effect is considered through the Carson reduction. It s important to point out that, in spite of the loads being normally connected to the transformer s secondaries, was considered the hypothesis of existence of star or delta loads connected to the primary circuit. To perform the simulation of voltage regulators, a new model was utilized, allowing the simulation of various types of configurations, according to their real functioning. Finally, was considered the possibility of representation of switches with current measuring in various points of the feeder. The loads are adjusted during the iteractive process, in order to match the current in each switch, converging to the measured value specified by the input data. In a second stage of the work, sensibility parameters were derived taking as base the described load flow, with the objective of suporting further optimization processes. This parameters are found by calculating of the partial derivatives of a variable in respect to another, in general, voltages, losses and reactive powers. After describing the calculation of the sensibility parameters, the Gradient Method was presented, using these parameters to optimize an objective function, that will be defined for each type of study. The first one refers to the reduction of technical losses in a medium voltage feeder, through the installation of capacitor banks; the second one refers to the problem of correction of voltage profile, through the instalation of capacitor banks or voltage regulators. In case of the losses reduction will be considered, as objective function, the sum of the losses in all the parts of the system. To the correction of the voltage profile, the objective function will be the sum of the square voltage deviations in each node, in respect to the rated voltage. In the end of the work, results of application of the described methods in some feeders are presented, aiming to give insight about their performance and acuity
Os programas desenvolvidos para o c?lculo de fluxo de carga sempre foram amplamente utilizados objetivando simular sistemas de transmiss?o, subtransmiss?o e distribui??o de energia el?trica. Entretanto, os m?todos matem?ticos aplicados para esse c?lculo estruturavam-se, em sua maioria, tomando como base apenas as caracter?sticas dos sistemas de transmiss?o, os quais eram o principal foco de preocupa??o dos engenheiros e pesquisadores. Todavia, as caracter?sticas f?sicas desses sistemas s?o bastante diferentes da realidade dos de distribui??o. Nos sistemas de transmiss?o, os n?veis de tens?o s?o altos e as linhas s?o geralmente muito longas. Esses fatores contribuem para que os efeitos capacitivos e indutivos que aparecem nos sistemas passem a ter uma influ?ncia consider?vel nos valores das grandezas de interesse, raz?o por que devem ser considerados. Ainda nos sistemas de transmiss?o, as cargas s?o de natureza macro, a exemplo de cidades, bairros, ou grandes ind?strias ou consumidores. Tais cargas s?o, em geral, praticamente equilibradas, o que reduz a necessidade de utiliza??o de metodologias trif?sicas para o c?lculo do fluxo. Os sistemas de distribui??o, por sua vez, pressup?em outras implica??es, apesar de os n?veis de tens?o serem pequenos em compara??o aos de transmiss?o, o que praticamente anula o efeito capacitivo das linhas. Como as cargas passam a ser, neste caso, transformadores, em cujos secund?rios est?o conectados pequenos consumidores, muitas vezes, monof?sicos, a possibilidade de se encontrar um circuito desbalanceado ? grande. Portanto, face a tal possibilidade, a utiliza??o de metodologias trif?sicas assume uma dimens?o importante. Al?m disso, equipamentos como reguladores de tens?o, para cujo funcionamento utilizam simultaneamente o conceito de tens?o de fase e de linha, necessitam de uma metodologia trif?sica, para que seu modelo permita simula??o em tempo real. Pelas raz?es expostas, o trabalho apresenta um m?todo de c?lculo de fluxo de carga trif?sico para sistemas de distribui??o de energia. No intuito de realizar tal tarefa, foi utilizado como base o m?todo Soma de Pot?ncias, j? bastante testado e aprovado na simula??o de sistemas radiais de distribui??o de energia el?trica. As linhas s?o a tr?s fios, considerando-se o acoplamento magn?tico entre as fases; j? o efeito da terra foi considerado atrav?s da corre??o de Carson. ? interessante ressaltar que, apesar de as cargas estarem normalmente conectadas nos secund?rios dos transformadores, foi considerada, al?m dessa possibilidade, a hip?tese da exist?ncia de cargas em estrela ou delta no circuito prim?rio. J? para a simula??o de reguladores de tens?o, foi utilizado um novo modelo que permite a simula??o dos v?rios tipos de configura??es, de acordo com o seu funcionamento real. Por fim, tamb?m foi considerada a possibilidade da representa??o com chaves de medi??o de corrente em diversos pontos do alimentador. As cargas s?o ajustadas, durante o processo iterativo, de maneira que a corrente em cada chave convirja para o valor especificado nos dados de entrada. Em uma segunda etapa, tomando como base o fluxo de carga descrito, o trabalho apresenta um m?todo de c?lculo para os par?metros de sensibilidade, com o objetivo de serem aplicados em processos de otimiza??o. Esses par?metros s?o encontrados atrav?s do c?lculo da derivada parcial de uma vari?vel com rela??o a uma outra, determinando a taxa de varia??o entre elas. Ap?s a descri??o de c?lculo dos par?metros de sensibilidade, apresenta-se o m?todo do gradiente, que usa esses par?metros para determinar o ponto ?timo de uma fun??o objetivo, que ser? definida para cada tipo de estudo. Neste trabalho s?o abordados dois tipos de problema. O primeiro refere-se ? redu??o das perdas t?cnicas em um alimentador de m?dia tens?o, atrav?s da instala??o de bancos de capacitores; o segundo trata do problema da corre??o do perfil de tens?o, atrav?s da instala??o de bancos de capacitores ou de reguladores de tens?o. No caso da redu??o das perdas ser? considerada, como fun??o objetivo, a soma das perdas em todos os trechos do sistema. J? para a corre??o do perfil de tens?o, a fun??o objetivo ser? a soma do quadrado dos desvios de tens?o em cada n?, com rela??o ? tens?o requerida. No final do trabalho, os m?todos descritos foram aplicados em alguns alimentadores com a finalidade de testar o seu desempenho e precis?o

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Alves, Bruna Pardim. "Busca tabu reformulada aplicada ao problema de operação de sistemas de distribuição de energia elétrica radiais /." Ilha Solteira, 2019. http://hdl.handle.net/11449/182469.

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Orientador: Ruben Augusto Romero Lazaro
Resumo: Este trabalho apresenta uma proposta baseada na meta-heurística Busca Tabu, chamada de Busca Tabu Reformulada para resolver o problema de operação ótima dos sistemas de distribuição, utilizando uma estratégia integrada de reconfiguração e alocação de bancos de capacitores fixos e chaveados para obter a topologia radial que apresente o menor custo de operação. Para encontrar a topologia radial inicial foi aplicado o algoritmo de Prim, em que foi obtida uma solução reconfigurada, e essa solução encontrada foi submetida à uma heurística para alocação de capacitores fixos e chaveados. A proposta de solução inicial é submetida ao algoritmo de Busca Tabu Reformulada que utiliza uma vizinhança que considera como solução vizinha uma topologia vizinha da topologia radial corrente e com a proposta de alocação de bancos de capacitores modificada. Como proposta da metodologia Busca Tabu Reformulada o procedimento é repetido até um critério de parada definido. Todos os programas foram escritos em linguagem FORTRAN 77. Os algoritmos propostos foram testados com os sistemas de 33, 70, 84 e 136 barras.
Abstract: This paper presents a proposal based on the Tabu Search metaheuristic called Tabu Search Reformulated to solve the problem of optimal operation of the distribution systems, using an integrated strategy of reconfiguration and allocation of fixed and switched capacitor banks to obtain the radial topology which presents the lowest operating cost. To find the initial radial topology the Prim algorithm was applied, in which a reconfigured solution was obtained, and this solution was submitted to a heuristic for the allocation of fixed and switched capacitors. The initial solution proposal is submitted to the Reformulated Tabu Search algorithm that uses a neighborhood that considers as neighbor solution a neighboring topology of the current radial topology and with the proposed allocation of modified capacitor banks. As a proposal of the Tabu Search Reformulated methodology, the procedure is repeated up to a defined stop criterion. All the programs were written in FORTRAN 77 language. The proposed algorithms were tested with the 33, 70, 84 and 136-node systems.
Mestre

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39

Junior, Walter Luiz Siqueira. ""Estudo de alguns parâmetros salivares em indivíduos com síndrome de DOWN"." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/23/23140/tde-13062005-115943/.

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O objetivo deste estudo foi mensurar o fluxo salivar, pH, capacidade tampão, concentrações de proteína total e ácido siálico, atividades das enzimas amilase e peroxidase e concentração dos íons sódio, potássio, cálcio, fósforo, zinco e magnésio em saliva total de indivíduos síndrome de Down com idade entre 1 e 25 anos. Nos indivíduos com idade entre 1 e 5 anos a saliva total foi coletada através de uma leve sucção, enquanto que nos outros indivíduos com idade entre 6 e 10, 11 e 15, 15 e 20, 21 e 25 a saliva total foi coletada com estimulação mecânica através da mastigação de parafilm, durante 10 minutos. O pH e a capacidade tampão foramdeterminadas usando um pHmetro digital. A capacidade tampão foi mensurada através de titulação com HCl a 0,01N. A concentração de eletrólitos foi determinada através de um espectrofotômetro de emissão atômica com fonte de excitação de argônio induzido. A proteína total foi mensurada através do reagente de Folin. A atividade da amilase foi mensurada através da produção de maltose e a atividade da peroxidase foi mensurada através da utilização de orto-dianisidina. Para a analise estatística os dados foram apresentados em media ± desvio padrão. Foi utilizado o teste t de Student para determinar as diferenças entre as medias dos indivíduos síndrome de Down e o grupo controle. Nenhuma diferença significante foi observada na concentração de ácido siálico, fósforo, zinco, magnésio e cálcio entre os indivíduos síndrome de Down e o grupo controle. A concentração de sódio, proteína total e a capacidade tampão demonstraram ser maior nos indivíduos com síndrome de Down em comparação ao grupo controle. Por outro lado, o fluxo salivar, a concentração de potássio, e a atividade das enzimas amilase e peroxidase foram menores no grupo síndrome de Down quando comparado ao grupo controle. Estes resultados sugerem que as pessoas com síndrome de Down apresentam alterações no metabolismo do ducto e/ou das células acinares das glândulas salivares.
The aim of this study was to measure the flow rate, pH, buffer capacity, sialic acid, total protein concentrations, amylase and peroxidase activities and sodium, potassium, calcium, phosphorus, zinc and magnesium concentration whole saliva of individuals with Down syndrome aged 1 - 25 years. In individuals aged 1-5 years the whole saliva was collected under slight suction, while in the others individuals aged 6-10, 11-15, 15-20, 21-25 the whole saliva was collected with stimulation by chewing a piece of parafilm, for 10 minutes. The pH and the buffer capacity were determined using a digital pHmeter. The buffer capacity was measured by titration with 0.01 N HCl. Electrolyte concentrations were determined by inductively coupled argon plasma with atomic emission spectrometry. Sialic acid was determined by thiobarbituric acid assay. Protein was determined by the folins phenol reagent. Amylase was assayed measuring the maltose produced by the breakdown of starch and peroxidase with ortho dianisidine. For statistical analysis the date are presented as mean ± SD. Students t test was used to determine differences between the mean of the Down syndrome and control groups. No statistically significant differences were observed in sialic acid, phosphorus, zinc, magnesium and calcium concentration between the individuals with Down syndrome and control group. The sodium and total protein concentration and buffer capacity showed higher in the Down syndrome than in the control group. On the other hand the flow rate and potassium concentration, amylase and peroxidase activities were lower in the Down syndrome than in the control group. These results suggest that the Down syndrome persons present alteration in the metabolism of the duct and/or acinar cells of salivary glands.

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Santos, Ricardo Viol dos. "Metodologia para alocação discreta e assimétrica de capacitores em sistemas elétricos de distribuição visando redução de desequilíbrio." Universidade Federal de Juiz de Fora (UFJF), 2015. https://repositorio.ufjf.br/jspui/handle/ufjf/4178.

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CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Buscando corrigir aspectos relacionados à qualidade de energia, bancos de capacitores em derivação são utilizados em alimentadores primários dos sistemas de distribuição. A busca pela melhor forma de alocação constitui um problema complexo de natureza matemática combinatória, ao incluir critérios técnicos conflitantes e restrições do sistema. Este problema não tem solução trivial, tornando-se importante a formulação de metodologias para auxiliar nessa tarefa. Neste trabalho, é proposta uma metodologia para alocação de bancos de capacitores em derivação em nós do sistema elétrico, com possibilidade de alocação desequilibrada, considerando sua natureza discreta, com objetivo de minimizar desequilíbrios de tensão e custos de alocação, baseada em aplicação de algoritmo genético. Foram consideradas também restrições tais como limites de correntes nos alimentadores, limites de tensão para a conformidade com as faixas adequadas de tensão padronizadas pelos órgãos competentes e a disponibilidade de bancos.
Seeking for correcting issues related to power quality, shunt capacitor banks are used in primary feeders of distribution systems. The search for the best allocation is a complex problem of combinatorial mathematical nature, including conflicting technical criteria and constraints of the system. This problem has nontrivial solution, making important the development of methodologies to assist in this task. In this work, it is proposed a methodology for allocation of shunt capacitor banks in electric system nodes, with the possibility of unbalanced allocation, considering its discrete nature, with the purpose of minimizing voltage imbalances and allocating costs, based on genetic algorithm application. Restrictions such as limits of current feeders, voltage limits for compliance with the appropriate standard voltage ranges and the availability of capacitor banks were considered.

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Vauzour, David. "Étude des propriétés biologiques des constituants des vins de Champagne." Phd thesis, Université Montpellier I, 2004. http://tel.archives-ouvertes.fr/tel-00460764.

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Il a été observé dans le cadre d'enquêtes épidémiologiques tentant d'expliquer le « French Paradox » qu'une consommation modérée et journalière de vin permet d'abaisser quantitativement les risques d'apparition d'accidents cardiovasculaires et/ou de cancer. La communauté scientifique s'est particulièrement intéressée aux vins rouges ou blancs, mais les études portant sur le vin de Champagne sont rares. Partant du Champagne en bouteille, il s'est donc agi dans un premier temps de préparer trois "blocs" représentant la totalité des constituants du Champagne en distinguant les Blancs de blanc des Blancs de noirs. Ils ont été séparés par Chromatographie de Partage Centrifuge, « bioguidée » en fonction des réponses des fractions à des tests d'activité biologique. Ainsi, en plus de celles connues jusque là, six nouvelles molécules ont pu être caractérisées par Résonance Magnétique Nucléaire et/ou spectrométries de masse et ultraviolette. Leurs propriétés biologiques ont alors été étudiées plus en détails, et en particulier dans les domaines de l'hémato-oncologie et de la neurobiologie. Des activités cytotoxiques et antiprolifératives sur des lignées cellulaires cancéreuses, un rôle protecteur sur des mitochondries isolées de cerveau de rat mises en anoxie et une inhibition de l'acétylcholinestérase, enzyme impliquée dans la maladie d'Alzheimer, ont clairement été identifiées in vitro pour les fractions issues des vins de Champagne. Leur pénétration au sein du cytoplasme de neurones, visualisée par des expériences de microscopie confocale de fluorescence, permet de faire l'hypothèse d'une action in vivo. L'analyse par cytométrie de flux des mécanismes biologiques impliqués dans les processus cytotoxiques et antiprolifératifs révèlent un phénomène apoptotique et une dérégulation du cycle cellulaire des lignées cancéreuses employées. De plus l'utilisation de puces à ADN nous a permis d'émettre des hypothèses quand aux voies de signalisation empruntées. En dehors de ces propriétés qui passent par des mécanismes moléculaires spécifiques, les constituants actifs du vin de champagne, assez largement représentés par des molécules polyphénoliques, ont fait l'objet de mesures de leurs propriétés rédox. L'étude menée in vivo sur la capacité antioxydante plasmatique de sujets sains après ingestion de deux coupes de Champagne démontre une contribution des substances naturelles des vins de Champagne dans la protection contre les espèces oxygénées réactives délétères pour l'organisme. Cette capacité antioxydante plasmatique est corrélée à une nette diminution du nombre de substances oxydantes plasmatiques, trente minutes après l'ingestion.

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42

Harter, Alexa Welsh. "The heat capacity of superfluid ^4He in the presence of a constant heat flux near Tλ." Thesis, 2001. https://thesis.library.caltech.edu/8606/1/Harter-aw-2001.pdf.

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We present the first experimental evidence that the heat capacity of superfluid ⁴He, at temperatures very close to the lambda transition temperature, T_λ,is enhanced by a constant heat flux, Q. The heat capacity at constant Q, C_Q,is predicted to diverge at a temperature T_c(Q) < T_λ at which superflow becomes unstable. In agreement with previous measurements, we find that dissipation enters our cell at a temperature, T_DAS(Q),below the theoretical value, T_c(Q). Our measurements of C_Q were taken using the discrete pulse method at fourteen different heat flux values in the range 1µW/cm² ≤ Q≤ 4µW /cm². The excess heat capacity ∆C_Q we measure has the predicted scaling behavior as a function of T and Q:∆C_Q • t^α ∝ (Q/Q_c)², where Q_cT) ~ t^2ν is the critical heat current that results from the inversion of the equation for T_c(Q). We find that if the theoretical value of T_c( Q) is correct, then ∆C_Q is considerably larger than anticipated. On the other hand,if T_c(Q)≈ T_DAS(Q),then ∆C_Q is the same magnitude as the theoretically predicted enhancement.

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43

Yang, Laurence. "A Bilevel Optimization Algorithm to Identify Enzymatic Capacity Constraints in Metabolic Networks - Development and Application." Thesis, 2008. http://hdl.handle.net/1807/10443.

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Constraint-based models of metabolism seldom incorporate capacity constraints on intracellular fluxes due to the lack of experimental data. This can sometimes lead to inaccurate growth phenotype predictions. Meanwhile, other forms of data such as fitness profiling data from growth competition experiments have been demonstrated to contain valuable information for elucidating key aspects of the underlying metabolic network. Hence, the optimal capacity constraint identification (OCCI) algorithm is developed to reconcile constraint-based models of metabolism with fitness profiling data by identifying a set of flux capacity constraints that optimally fits a wide array of strains. OCCI is able to identify capacity constraints with considerable accuracy by matching 1,155 in silico-generated growth rates using a simplified model of Escherichia coli central carbon metabolism. Capacity constraints identified using experimental fitness profiles with OCCI generated novel hypotheses, while integrating thermodynamics-based metabolic flux analysis allowed prediction of metabolite concentrations.

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George, Jessey. "Nitrate and ammonium interactions in maize." Thesis, 2014. http://hdl.handle.net/2440/97381.

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Nitrogen (N) is one of the major mineral nutrients required by a plant for its growth and development. Nitrate (NO₃⁻) and ammonium (NH₄⁺) are the predominant forms of N available to plants in agricultural soils. Plants have the ability to absorb both these forms efficiently from the soil solutions. With soil solution concentrations of NH₄⁺ being much lower (on average 10%) than NO₃⁻, contribution of these small amounts of NH₄⁺ to the overall N budget of crop plants is often overlooked. This research focussed on the contribution of this NH₄⁺ in the nitrogen economy of maize plants. The study also investigated whether NH₄⁺ has any effect on uptake and utilization of other nutrients, and most importantly, NO₃⁻. Growth of maize inbred line B73 was increased when one-third of total nitrogen was supplied as NH₄⁺ with low NO₃⁻, but not for another inbred line Gaspe Flint. Further investigations on B73 found a 20% increase in plant growth when supplied with 10% NH₄⁺ along with sufficient NO₃⁻. Ammonium being a cheaper N source and the low energy and carbon skeleton requirement for its assimilation has contributed in increased shoot dry matter accumulation in these plants. A corresponding increase in total N, total free amino acids and sugars in the leaves of these plants were observed. A positive correlation was seen between transcript levels of putative high affinity NO₃⁻ and NH₄⁺ transporters. This together with an increased activity of N assimilatory enzymes suggested that small amounts of NH₄⁺ can increase the uptake and assimilation of N in these plants. 10% NH₄⁺ in the nutrient solution does not inhibit the NO₃⁻ uptake capacity in plants but when the concentration was increased to 50% there is a reduction in NO₃⁻ uptake capacity for plants growing in low N. This indicates that high concentration of NH₄⁺ limit the absorption of NO₃⁻ which is an important signalling molecule for various metabolic activities in plants. Reduction in NO₃⁻ uptake capacity of plants grown in 10% NH₄⁺ at sufficient N was correlated with higher total free amino acids in the roots, particularly glutamine and asparagine. This reduction in NO₃⁻ uptake capacity when grown in small amounts of NH₄⁺ is a long term effect caused by the products of N assimilation and could be reversed by moving plants to solely NO₃⁻ treatments. Higher concentrations of amino acids in the roots of these plants suggests that NH₄⁺ that enters the root gets first into the assimilatory pathway in the cytosol prior to the assimilation of NH₄⁺ formed by the reduction of NO₃⁻ in the plastids. This study showed that small amounts of NH4 + improve plant growth and lead to major changes in N uptake and assimilation processes. Based on these effects and the fact that plants in the field always have a small amount of N available as NH₄⁺, it is recommended that NH₄⁺ be added to the experimental nutrient solutions with maize and the effect be explored in other major plant species.
Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2014

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Mabuza, Major. "Evaluating the adsorption capacity of supercritical carbon dioxide on South African coals using a simulated flue gas." 2013. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000996.

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M. Tech. Engineering Chemical.
Aims to investigate how the addition of impurities in a CO2 stream affects the adsorption capacity of CO2 on South African coals. To achieve this aim, the following objectives were carried out. 1. To measure the adsorption isotherms and adsorption capacities of pure CO2 and flue gas mixtures on various South African coals under in-seam conditions including pressures up to 88 bar and isothermal temperature of 35 º%x;C; 2. To evaluate the effects of coal rank on the adsorption isotherms and adsorption capacities of pure CO2 and flue gas mixtures; 3. To do a comparative study to evaluate the effects of CO2 impurities on the adsorption capacity of pure CO2 on coal; 4. To study the degree of preferential sorption of the individual flue gas mixtures components on coal; 5. To determine the suitability of the Langmuir, Freundlich, and Temkin adsorption isotherm models in representing pure CO2 adsorption onto coal; and 6. To determine the suitability of Extended Langmuir (EL) adsorption models in representing the flue gas mixture adsorption onto coal.

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Dissertations / Theses on the topic 'Flux capacity'

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