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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
301

Recuperação da amônia liberada no processo de \"air stripping\" aplicado ao tratamento do lixiviado de aterros sanitários / Recovery of ammonia released from air stripping process applied to sanitary landfill leachate treatment

Fernanda de Matos Ferraz 26 March 2010 (has links)
O lixiviado de aterros sanitários é um efluente líquido poluente devido, principalmente, à sua elevada concentração de amônia. Seu tratamento faz-se necessário para que sejam atendidas as exigências das legislações ambiental e trabalhista, além de minimizados os impactos ambientais de seu lançamento nos corpos d\'água. Esta pesquisa propõe a remoção da amônia presente no lixiviado por meio do processo físico-químico \"air stripping\", que promove a transferência da amônia da fase líquida para gasosa. Para que não se contribua com a poluição atmosférica, o efluente gasoso do \"air stripping\" deve ser tratado em solução de ácido sulfúrico ou água. A neutralização da amônia com solução de ácido sulfúrico gera o sulfato de amônio, e com água, a aquamônia. Tais subprodutos podem ser usados como fertilizantes. Nesta pesquisa, para remoção da amônia do lixiviado foi utilizada uma torre de PVC, com 2,24 m de altura e 15 cm de diâmetro, recheada com anéis do tipo Rashing de polietileno corrugados, com diâmetro de 1,5 cm e 5 cm de comprimento. As vazões de ar utilizadas foram 1200, 1600 e 3600 L/h e as vazões de lixiviado foram 18 e 30 L/h. Para ajuste no pH do lixiviado, utilizou-se hidróxido de cálcio (padrão analítico) e cal comercial. Os fluxos de líquido e ar eram em contracorrente. Para o recolhimento da amônia foram usados dois frascos de 6 L, preenchidos com 4 L de solução de ácido sulfúrico 0,4 mol/L ou água. Os resultados obtidos indicaram remoção praticamente completa de toda a amônia contida no lixiviado. Nas diferentes condições operacionais avaliadas, a concentração de amônia remanescente no lixiviado foi igual ou inferior aos 20 mg/L determinados pela Resolução 397/08 do CONAMA. Quanto ao recolhimento da amônia, a eficiência média obtida nos frascos lavadores próxima a 80%, tanto ) quando utilizada a solução de ácido sulfúrico 0,4 mol/L quanto quando utilizada água. / Sanitary landfill leachate is a pollutant liquid effluent mainly due to its high ammonia concentration. Its treatment is necessary due to environmental and labour legislation requirements, besides prevention of environmental impacts of leachate release in water bodies. This research proposes ammonia removal from leachate by air stripping process, which transfers ammonia from liquid to gaseous phase. In order to prevent atmospheric pollution, air stripping gaseous effluent must be treated with sulphuric acid solution or water. Ammonia neutralization by sulfuric generates ammonium sulfate and by water, aquammonia is generated. Such by-products may be used as fertilizer. In this research, in order to remove leachate ammonia it was used a PVC tower of 2.24 m high and 15 cm diameter, packed with Rashing rings of corrugated polyethylene of 1.5 cm diameter and 5 cm length. Air flows were 1200, 1600 and 3600 L/h and leachete flows were 18 e 30 L/h. Calcium carbonate (standard grade) and commercial hydrated lime were used for pH adjustments. Air and liquid flows were countercurrent. In order to recover ammonia, two flasks of 6 L were used and filled with 4 L of 0.4 mol/L sulfuric acid solution or water. Results showed that ammonia was almost completely removed from leachate. In all operational conditions evaluated, remaining ammonia concentration in leachate was equal or less than 20 mg/L, value established by Resolution 397/08 of Brazilian Council of the Environment. Ammonia recovery with water or a 0.4 mol/L sulfuric acid solution was about 80%.
302

Applying the RE-AIM Model to Asset-Based Community Health Interventions: A Multiple Case Study in Tower Hamlets, London, UK

Kaminska, Karolina January 2016 (has links)
Public health policy and practice principally acknowledge a needs-based approach when developing, implementing, and evaluating community health programs. This needs-based perspective receives criticism because it focuses too heavily on what is missing or wrong with communities as opposed to building on their strengths. As a result, community members are perceived as passive recipients, which is disempowering, and ultimately risks creating unsustainable and ineffective programs. In recent years, there has been a growing interest in achieving a balance between the needs-based approach and the asset-based approach, which accentuates positive capabilities. While the amount of literature discussing the benefits of this latter perspective has grown substantially, accompanying evaluation required to sustain continued investment has been limited. Compared to needs-based research, there is less literature on asset-based evaluation. Emphasis on such research could contribute to the progression of evaluation methodologies and theories, ultimately encouraging their use. The purpose of this study is to apply an existing public health evaluation framework – the RE-AIM model (Glasgow, Vogt, and Boles, 1999) – to asset-based community health interventions and to examine the utility of such an evaluation structure across a variety of asset-based health projects. A multiple case study design facilitated comparison of the applicability of the RE-AIM model dimensions – Reach, Effectiveness, Adoption, Implementation, and Maintenance across three cases in the East London borough of Tower Hamlets, United Kingdom. These included the Local Links Asset-mapping project, the Healthy Early Years Project, and the Good Moves project. The RE-AIM framework is additionally guided by principles of the Realist Evaluation approach (Pawson and Tilley, 1997). This research study contributes to asset-based research by providing a guideline and conceptual framework to support asset-based intervention evaluation theory and practice.
303

Les églises fortifiées du département des Landes / Fortified churches department of Landes

Ratto, Jean-Bernard 29 January 2014 (has links)
Le département des Landes correspondant actuellement au diocèse d'Aire et de Dax, est constitué par le regroupement des anciens diocèses d'Aire et de Dax augmentés de portions de ceux d'Auch, Bazas et Bordeaux. Les édifices religieux de ce département sont fortifiés au cours de la période s'échelonnant du début du conflit franco-anglais, à la fin du XIIIe siècle, puis pendant la guerre de Cent Ans, et, pour certains, jusqu'au milieu du XVIe siècle. La grande majorité d'entre-eux sont de modestes églises destinées à la défense des populations des villages dans une région marquée par la relative rareté des châteaux. Elles sont fortifiées de façon quelquefois très élaborée et souvent très sommaire. Elles sont particulièrement éprouvées lors des guerres de Religion, période pendant laquelle elles sont presque toutes pillées, souvent incendiées et détruites au niveau de leur voûtement. Leur inventaire dans ce département est constitué de plus de soixante-quinze églises. Soixante-huit d'entre-elles font l'objet d'une notice détaillée, avec plan, historique, description architecturale, photos, relevés, description et analyse des fortifications. D'autres édifices religieux des Landes, et certains appartenant à des départements différents, ayant un rapport direct avec ce sujet, sont également mentionnés. Cette recherche a permis de révéler la grande quantité et la diversité des églises fortifiées de cette région et leurs différents modes de mise en défense. Elle a également mis en évidence un type particulier et rare de fortification constitué par des façades ou des porches semi-circulaires édifiés dans la seconde moitié du XVe siècle ou au début du XVIe siècle. L'étude comparative de ces constructions semi-circulaires de façade, à usage militaire, avec les églises à contre-abside, à usage liturgique, existant encore dans les Landes et en Aquitaine, a été faite afin de bien distinguer les deux types d'édifices. / The Landes currently corresponding to the diocese of Aire and Dax, is formed by the combination of the former dioceses of Aire and Dax plus those portions of Auch, Bazas and Bordeaux. Religious buildings of this department are strengthened during the period from the beginning of the Anglo-French conflict in the late thirteenth century, and during the Hundred Years War, and for some, until the mid-sixteenth century. The vast majority of them are small churches for the defense of the village population in a region marked by the relative scarcity of castles. They are fortified so sometimes very elaborate and often very brief. They are particularly affected during the Wars of Religion, during which they are almost all looted, burned and destroyed often in their vault. Their inventory in this department consists of more than seventy-five churches. Sixty-eight of them are subject to detailed instructions, with plan, historical, architectural description, photos, statements, description and analysis of fortifications. Other religious buildings in the Landes, and some belonging to different departments, having a direct bearing on this subject are also mentioned. This research revealed the large amount and variety of fortified churches in this region and their different modes of defense. She also highlighted a particular and rare fortification consists of facades or semicircular porches built in the second half of the fifteenth century or early sixteenth century. The comparative study of these constructions semicircular facade for military use, with the churches against the apse, in liturgical use, still existing in the Landes and Aquitaine, was made to distinguish between the two types of buildings.
304

Evaluation de la fiabilité des éléments de charpente de grue à tour / Reliability assessment of tower crane structural members

Bucas, Simon 09 January 2015 (has links)
Les grues à tour sont des engins de levage utilisés de manière cyclique sur les chantiers de construction. De ce fait, la prise en compte du phénomène de fatigue dans le dimensionnement des charpentes de grue est primordiale. La fatigue est usuellement considérée dans les normes au moyen de règles déterministes ayant pour but de garantir l’intégrité de la structure sous diverses conditions d’utilisation. Bien que cette approche fournisse des résultats satisfaisants dans la plupart des cas, celle-ci ne permet pas d’évaluer le niveau de fiabilité des éléments de charpente en fonction de leur durée d’exploitation. De ce point de vue, les approches probabilistes permettent de pallier cette difficulté en proposant des outils pertinents servant à caractériser et à propager les incertitudes liées à la fatigue au travers d’un modèle mécanique. Une approche probabiliste originale permettant la prise en compte des incertitudes liées à la fatigue dans le dimensionnement des charpentes de grues à tour est proposée dans ce manuscrit. La méthode proposée est basée sur la définition de deux densités de probabilité représentant respectivement les variabilités liées à la résistance des joints soudés d’une part, et les nombreuses dispersions associées à la sollicitation des éléments de charpente d’autre part. La définition de la densité de probabilité de résistance repose sur la capitalisation d’un grand nombre de résultats d’essais d’endurance sur structures soudées, tandis que la définition de la distribution de sollicitation est basée sur une modélisation à deux niveaux tenant compte de divers jeux de données collectés sur chantier. Les résultats de l’analyse de fiabilité présentée dans ce manuscrit démontrent la pertinence des approches probabilistes dans le cadre du dimensionnement en fatigue des éléments de charpente de grue à tour. / Tower cranes are lifting appliances which are cyclically used on construction sites. Thus, the consideration of the fatigue phenomenon in the design of crane structural members is essential. This phenomenon is usually taken into account in standards by means of deterministic rules enabling to ensure structural safety under various operating conditions. Although it provides satisfactory results in most cases, the deterministic approach do not enable to evaluate the reliability of crane structural members according to their operating time. From this point of view, probabilistic approaches allow to overcome this difficulty by proposing relevant tools enabling to characterize and propagate uncertainties related to fatigue through a mechanical model. An original probabilistic approach enabling the consideration of the uncertainties related to crane members fatigue design is proposed in this manuscript. It relies on the definition of two probability density functions related respectively to the strength variability of crane welded joints on one hand, and the dispersion of operating conditions (stress) on this other hand. The definition of the strength distribution stems from the capitalization of various welded joint fatigue test results, while the characterization of the stress distribution relies on the analysis of various data sets coming from crane monitoring performed on different construction sites. The results coming from the reliability analysis presented in this manuscript show the relevance of probabilistic approaches in the frame of tower crane structural members fatigue design.
305

Mobile Emergency Cooling System for Decay Heat Removal : Cooling Tower Designs for Forsmark NPP

Hissein Koty, Habre January 2019 (has links)
This master thesis has been conducted at Forsmark nuclear power plant. In nuclear power plants, safety is one of the most important tasks. After the Fukushima-accident, Forsmarks Kraftgrupp AB investigated the possibility to have additional emergency cooling systems. This thesis aims to investigate the use of cooling towers as mobile emergency cooling system for decay heat removal for the nuclear reactors at Forsmark NPP. The advantages and disadvantages of different cooling tower types were looked at. To achieve mobility, some restraints were considered such as dimensions and weight. In the design of cooling towers, experimental values are used. As these crucial data are missing, a backfitting from actual designs was done to derivate the missing data. The results of this thesis show that wet cooling towers are in this case more effective than dry cooling towers. The wet cooling towers cover in the best scenario up to 38MW which is 10 times higher than what can be achieved with the dry cooling tower. That covers the maximal decay heat released in the reactor F3 12 hours after a shutdown.
306

P-adic local Langlands correspondence and geometry / Langlands p-adique : géometrie et programme

Chojecki, Przemyslaw 16 January 2015 (has links)
Cette these concerne la geometrie de la correspondance de Langlands p-adique. On donne la formalisation des methodes de Emerton, qui permettrait d'etablir la conjecture de Fontaine-Mazur dans le cas general des groupes unitaires. Puis, on verifie que ce formalism est satisfait dans la cas de U(3) ou on utilise la construction de Breuil-Herzig pour la correspondence p-adique. De point de vue local, on commence l'etude de cohomologie modulo p et p-adiques de tour de Lubin-Tate pour GL_2(Q_p). En particulier, on demontre que on peut retrouver la correspondence de Langlands p-adique dans la cohomologie completee de tour de Lubin-Tate. / This thesis concerns the geometry behind the p-adic local Langlands correspondence. We give a formalism of methods of Emerton, which would permit to establish the Fontaine-Mazur conjecture in the general case for unitary groups. Then, we verify that our formalism works well in the case of U(3) where we use the construction of Breuil-Herzig as the input for the p-adic correspondence.From the local viewpoint, we start a study of the modulo p and p-adic cohomology of the Lubin-Tate tower for GL_2(Q_p). In particular, we show that we can find the local p-adic Langlands correspondence in the completed cohomology of the Lubin-Tate tower.
307

Théorie des représentations combinatoire de tours de monoïdes : Application à la catégorification et aux fonctions de parking / Combinatorial representation theory of tower monoids : Application to categorification and to parking functions

Virmaux, Aladin 13 June 2016 (has links)
Cette thèse se situe en combinatoire algébrique, et plus particulièrement en théorie combinatoire des représentations linéaires des monoïdes finis.Rappelons qu'un monoïde est un ensemble fini M muni d'une multiplication et d'un élément neutre, et qu'une représentation de M est un morphisme de M dans le monoïde des matrices $M_n(ck)$ où $ck$ est un corps, typiquement $ck =CC$. Les résultats des dernières décennies donnent un contrôle assez fin sur les représentations des monoïdes, permettant souvent de se ramener à de la théorie des représentations des groupes et de la combinatoire sur des préordres.En 1996, Krob et Thibon ont montré que l'induction et la restriction des représentations irréductibles et projectives de la tour des $0$-algèbres de Hecke $H_n(0)$ permet de munir l'ensemble des caractères d'une structure d'algèbre de Hopf, qui est isomorphe a l'algèbre de Hopf $ncsf$ des fonctions symétriques non commutatives. Cela donne une emph{catégorification} de$ncsf$, c'est-à-dire une interprétation de celle-ci en terme de théorie des représentations. Ils prolongent ainsi un résultat dû à Frobenius établissant un lien entre l'anneau des caractères de la tour des groupes symétriques et lesfonctions symétriques. Un problème naturel depuis lors est d'essayer de catégorifier d'autres algèbres de Hopf -- par exemple l'algèbre $pbt$ desarbres binaires de Loday et Ronco -- par des tours d'algèbres.Deviner une telle tour d'algèbres est difficile en général. Dans le cadre de cemanuscrit on restreint le champ de recherche aux tours de monoïdes, afin de mieux contrôler leurs représentations. C'est naturel car ce cadre couvre enfait les deux exemples fondamentaux ci-dessus, tandis qu'il est impossible decatégorifier $ncsf$ avec seulement une tour de groupes.Nous commençons par donner quelques résultats sur les représentations des toursde monoïdes. Ensuite, nous nous intéressons à la catégorification par destours de semi-treillis, et en particulier de quotients du permutoèdre. Avecceux-ci, nous catégorifions la structure de cogèbre de $fqsym$ sur la base$gbasis$ et celle d'algèbre de $fqsym$ sur la base $fbasis$. Cela ne permetcependant pas de catégorifier simultanément toute la structure de Hopf de ces algèbres. Dans un second temps, nous menons une recherche exhaustive des catégorifications de $pbt$. Nous montrons que, sous des hypothèses naturelles,il n'existe pas de catégorification de $pbt$ par une tour de monoïdesapériodiques. Enfin, nous démontrons que, dans un certain sens, la tour des monoïdes $0$-Hecke est la tour de monoïdes la plus simple catégorifiant $ncsf$.La seconde partie porte sur les fonctions de parking, par application des résultats de la première partie. D'une part, nous étudions la théorie des représentations de la tour des fonctions de parking croissantes. D'autre part,dans un travail commun avec Jean-Baptiste Priez nous reprenons une généralisation des fonctions de parking due à Stanley et Pitman. Afin d'obtenir des formules d'énumérations, nous utilisons une variante -- plus efficace dansle cas présent -- de la théorie des espèces. Nous donnons une action de$H_n(0)$ (et non du groupe symétrique) sur les fonctions de parking généralisées, et utilisons le théorème de catégorification de Krob et Thibon,pour relever dans les fonctions symétriques non commutatives le caractère de cette action. / This thesis is focused on combinatorical representation theory of finitemonoids within the field of algebraic combinatorics.A monoid $M$ is a finite set endowed with a multiplication and a neutralelement. A representation of $M$ is a morphism from $M$ into the monoid ofmatrices $M_n(ck)$ where $ck$ is a field; in this work it will typically bereferred to as $ck = CC$.The results obtained in the last decades allows us to use representation theoryof groups, and combinatorics on preorders in order to explore representationtheory of finite monoides.In 1996, Krob and Thibon proved that the induction and restriction rules ofirreducible and projective representations of the tower of $0$-Hecke monoidsendows its ring of caracters with a Hopf algebra structure, isomorph to thenon-commutative symmetric functions Hopf algebra $ncsf$. This gives acategorification of $ncsf$, which is an interpretation of the non-commutativesymmetruc functions in the language of representation theory. This extends atheorem of Frobenius endowing the character ring of symmetric groups to theHopf algebra of symmetric functions. Since then a natural problem is tocategorify other Hopf algebras -- for instance the Planar Binary Tree algebraof Loday and Ronco -- by a tower of algebras.Guessing such a tower of algebra is a difficult problem in general.In this thesis we restrict ourselves to towers of monoids in order to have abetter control on its representations. This is quite natural as on one hand,this setup covers both previous fundamental examples, whereas $ncsf$cannot be categorified in the restricted set of tower of group algebras.In the first part of this work, we start with some results about representationtheory of towers of monoids. We then focus on categorification with towers ofsemilatices, for example the tower of permutohedrons. We categorify thealgebra, and cogebra structure of $fqsym$, but not the full Hopf algebrastructure with its dual. We then make a comprehensive search in order tocategorify $pbt$ with a tower of monoids. We show that under naturalhypothesis, there exists no tower of monoids satisfying the categorificationaxioms. Finally we show that in some sense, the tower of $0$-Hecke monoids isthe simplest tower categorifying $ncsf$.The second part of this work deals with parking functions, applying resultsfrom the first part. We first study the representation theory of non decreasingparking functions. We then present a joint work with Jean-Baptiste Priez on ageneralization of parking functions from Pitman and Stanley. To obtainenumeration formulas, we use a variant of the species theory which was moreefficient in our case.We used an action of $H_n(0)$ instead of the symmetric group and use theKrob-Thibon theorem to lift the character of this action into the Hopf algebraof non-commutative symmetric functions.
308

Požární stanice Zbýšov / The fire station in Zbýšov

Stuchlíková, Michaela January 2018 (has links)
The thesis contains a fire station type P1 and object of gym in the administrative area Zbýšov u Oslavan. There is a fire station is build with three floors and the gym with two floors. The design of the fire station is followed accordingly with ČSN 73 5710, it contains premises for administration, day and nigh emergency, training tower and garage and gym. The building with build of ceramic blocks (Porotherm). The ceilings are prefabricated of the pre stressed ceiling slabs. The flats roof is single-skinned and the perimeter casing is made of ventilated facade.
309

Ocelová rozhledna / Steel lookout tower

Kábrt, Michal January 2018 (has links)
The aim of the diploma thesis was to make a structural design of steel-load-carrying structure of steel lookout tower, in the grounds of domestic brewery in Humpolec. Lookout tower will be part of newly built centre for customers of the brewery. The layout and shape of the load-carrying structure of steel lookout tower follow the brewery chimney with height of 32.7 m with circular ground plan and outside diameter of 3.5 m in the heel and 2.3 m at the top. The chimney is independent of the construction of the lookout tower. The ground plan and dimensions of the lookout tower were considered taking into account the required spacing of the structure from adjacent buildings and ensuring sufficient dimensions for the required passage between the future lookout tower and the existing building of the boiler room. RFEM was used for calculation internal forces and assessment on individual structural elements, according to the valid Eurocodes.
310

Porovnání klasického AlFe vedení s technologiemi ACCC / The comparison of classic AlFe line with ACCC technologies

Hrachiar, Róbert January 2018 (has links)
The diploma thesis deals with the comparison of the conduction with the classic "AlFe" ropes (ACSR technology - aluminium conductor steel reinforced) and the line with the ACCC technology (aluminum core composite core). The first part describes the development of the transmission and distribution network in the Czech Republic. Subsequently types of conductors are described, its construction and main characteristics. The theoretical part also consists of theoretical knowledge about compared types of conductors and knowledge from the field of external lines. During the creation of the theoretical part of the thesis, we gained experience in the advanced functions of Excel, which are later used in practical part. The practical part of the thesis consists of creation of the calculation program itself, instructions and calculation methodology. Included is also an example of use of the program that compars two types of conductors of the same diameter, the same transmitted current and the same weight per unit length.

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