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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.
151

Temporal and spatial effects of a long term large scale alley farming experiment on water table dynamics : implications for effective agroforestry design

Noorduijn, Saskia L. January 2009 (has links)
[Truncated abstract] Removal of native vegetation to facilitate traditional agriculture practices has been shown to reduce ecosystem health, and restricts the native habitat. The subsequent change in the predominant vegetation water use patterns has altered the catchment water balance, and hydrology which results in land degradation through such processes of salinisation and water logging. More recently, moves toward more sustainable farming practices have been taken to help re-establish catchment hydrological equilibrium and improve catchment ecosystem services. Agroforestry is one such vehicle for this reestablishment. Perennial native vegetation has been shown to have a significant effect on catchment processes, mitigating any further degradation of the land. The effect of alternating native perennial tree belts with traditional broad acre agriculture in the alleys, referred to as alley farming, is investigated in this thesis due to the potential environmental and economic benefits that can result. This thesis investigates the impact of tree belts upon the water table and aims to gauge the ability of alley farming at controlling recharge within the low-medium rainfall zone on the valley floor. The basis of this research is the analysis of data collected from the Toolibin Alley Faring Trial. This experiment was established in 1995 to assess the viability of alley farming and incorporates different combinations of belt width, alley width and revegetation density. Transects of piezometers within each design have been monitored from October 1995 to January 2008. The piezometers were sporadically monitored over this period on a total of 39 dates. ... To further understand the response observed in the water table data, in depth hydrograph analysis of the control piezometer water levels was conducted. The statistical analysis demonstrates that the belts are having a very limited impact on the water table morphology, this is associated with the restricted use of groundwater by the perennial tree belts due to the poor quality, has been applied. This explains why there is limited signature of increased water table depth in the statistical analysis; there is evidence that alley farming as a means of reducing recharge may work however the overriding control on the trial are the rainfall trends rather than perennial growth. The low perennial biomass production at the site is an effect of limited water resources; however a significant distinction can be made between the water table depth and variability beneath high and low biomass belts. There are three main controls at the site; climate, development of perennial biomass and development of perennial root systems (both vertically and laterally). The regional climatic trends will influence water table levels creating a greater soil water storage capacity; therefore the contribution of soil water to transpiration rates will enable the tree belts to have some impact on recharge. Of the alley farming designs tested, the optimal planting density and belt/alley design, from an economic perspective, is identified as having a 4m belt width which generated the greatest biomass. As a means of controlling recharge at the site the effectiveness of alley farming is limited due the shallow saline water table limiting perennial growth.
152

Carbonate alteration of serpentinite in the Murchison Greenstone Belt, Kaapvaal craton : implications for gold mineralization.

Madisha, Moropa Ebenezer 15 August 2012 (has links)
M.Sc. / Please refer to full text to view abstract
153

Ubytovací zařízení / Accommodation facility

Šindlář, Josef January 2019 (has links)
The subject of this master thesis is a project for the construction of accommodation facility with a basement. The building is located in Ostrava close to the historical centre of the city. The building is a 4starcategory accommodation facility and will serve as temporary accommodation. There will be a restaurant and a gym designed for hotel guests only. The accommodation capacity is 68 guests. A car park for hotel visitors is situated close to the hotel. It is a brick structure made of sand-lime blocks,monolithic ceilings and a first underground floor. The building is insulated with ETICS system. Paste-like plaster and brick tapes were used for facade construction. The roof is made up of one roof surface and the foundation will be realized on the foundation strips. The building is situated on flat terrain. The project was developed in ArchiCad21, AutoCad 2016 and SketchUp.
154

Physical and numerical modeling of the dynamics of high-energy electrons trapped in the outer radiation belt of the Earth’s magnetosphere / Modélisation physique et numérique de la dynamique des électrons de haute énergie piégés dans la ceinture de radiation externe de la magnétosphère terrestre

Loridan, Vivien 17 October 2018 (has links)
Les satellites sont vulnérables aux particules de forte énergie piégées dans les ceintures de Van Allen. Afin d’en assurer la protection, il est nécessaire de prédire avec précision la dynamique des électrons au sein de la magnétosphère. Dans un premier temps nous proposons une méthode originale de résolution analytique de l’équation de Fokker-Planck réduite qui modélise le transport et les pertes des électrons de la magnétosphère interne. La résolution repose sur une technique de décomposition spectrale. Si la solution analytique s’avère utile pour mettre en exergue certaines propriétés physiques des ceintures de radiation, elle est également pertinente pour valider le code numérique de résolution de l’équation de Fokker-Planck réduite, développé durant la thèse. Ce dernier nous amène à généraliser l’étude précédente en illustrant l’évolution des flux d’électrons pour diverses énergies et positions. Nous prouvons notamment que la structure des ceintures de radiation ainsi que leur temps d’évolution ne dépendent que de quelques facteurs bien choisis. Dans la perspective de reproduire un événement particulier de retour au calme après un orage magnétique, mesuré par les satellites de la NASA dédiés aux ceintures de radiation, nous sommes en mesure de simuler la précipitation des électrons dans l’atmosphère terrestre causée par les interactions avec les ondes électromagnétiques de la magnétosphère. L’utilisation de conditions bâties sur des données empiriques et spécifiques à la période en question nous permet de corroborer les flux observés. Enfin, l’influence du champ magnétique terrestre sur la dynamique des ceintures de radiation est étudiée sous divers aspects. Nous nous concentrons sur la ceinture externe pour comprendre comment les asymétries du champ magnétique, considérablement façonnées par l’activité solaire, affectent notre manière de concilier théorie et observations. Nous explorons également l’importance de certains processus diffusifs nouveaux et cachés, qui émergent à cause de l’irrégularité naturelle du champ magnétique au plus proche voisinage de la Terre. / Satellites are vulnerable to high-energy particles trapped in the Van Allen belts. To ensure their protection, it is necessary to predict properly the electron dynamics in the magnetosphere. We first propose an original method to find the analytical solution of the reduced Fokker-Planck equation that models the transport and loss of electrons in the inner magnetosphere. The resolution relies on an eigenfunction expansion approach. If the analytical solution is proven to be useful at uncovering some of the physical properties of the radiation belts, it is also relevant to validate the numerical code that solves the reduced Fokker-Planck equation, which has been developed during the PhD. The latter code is used to generalize the previous study in illustrating the evolution of the electron fluxes for various energies and locations. We demonstrate that the structure of the radiation belts as well as their dynamical timescales only depend on a few well-chosen parameters. In the perspective of reproducing a specific storm-recovery event reported by the NASA Van Allen Probes, we are able to simulate the electron scattering in the Earth’s atmosphere due to the interaction with magnetospheric electromagnetic waves. The consideration of data-driven and event-specific conditions enables us to corroborate the observed fluxes. Finally, various influences of the Earth’s magnetic field on the dynamics of the radiation belts are investigated. We focus on the outer belt to see how the magnetic field asymmetries, which are strongly shaped by solar activity, affect the way of conciliating theory and observations. We also explore the importance of new hidden diffusive processes that emerge due to the natural irregularity of the magnetic field in the closest vicinity of the Earth.
155

Možnosti využití různých druhů popílků při výrobě oxidovaných asfaltových izolačních pásů / Possibilities of utilisation different types of fly ashes in the production of oxidized asphalt insulation strips

Sklenářová, Radka January 2019 (has links)
Reducing the impact of modern industrial production on the environment and reducing the waste generated is undoubtedly one of the most discussed topics of the present time. In the production of fossil-fueled electricity, a large amount of fine-grained waste fly ash is generated. The possible use of ash as secondary raw materials in the construction and building materials industry is one of the many environmental challenges that the energy industry is concerned with. The aim of this diploma thesis was to verify possibilities of utilization of different kinds of power station fly ash as filler in asphalt mixtures for the production of oxidized asphalt insulation strips. The main emphasis was put on the clarification of the influence of the properties of the different types of fly ashes on the resulting rheological behavior of the mixture of asphalt binder and power fly ash, which is professionally called mastic. Mastic forms a technology-critical insulating layer in the asphalt insulation strip. The prediction of the rheological properties and therefore the workability of mastic appears to be an essential element in the management of production, especially under the conditions of the variability of input raw materials. In order to solve the assigned task it was necessary to perform detailed analyzes of fly ash properties, to select the corresponding quantification variable for assessment of the mastic processability and to find the signal fly ash properties, which appears to be a control parameter of workability. As a suitable method for assessing the processability of mastic, a shear viscosity measurement method was chosen. On the basis of the findings, it is possible to state that the use of fly ash from the production of oxidized asphalt bands is not recommended as the mastic prepared from these fly ashes are unprocessed at the assumed concentrations. The negative effect of fly ash after denitrification on the mastic processability has not been demonstrated.
156

B + B BARCELONA / B + B BARCELONA

Křikavová, Iva January 2010 (has links)
B+B Barcelona/master’s thesis/Iva Křikavová/studio of Ivan Koleček/2010 Urban Plan of Poble Nou district of Barcelona in the past was strongly defined, factory halls fully built the block, streets and squares had a clear structure. Industry terminated operations and adjacent diagonals became attractive for various companies, hotels and developers, who started to build. Thirty-storey houses with undefined environment, the structure is lost, chaos prevails. To preserve the character of the plan, the old and the newly formed buildings, became a clear definition of the school block. Definition of block one hundred years ago lay in the absolute middle of the courtyard, but how to behave now in 2010? The answer is to define a block with three houses, each of then has its function - school, sports, library and dining room. Among them are moving teachers and students, experiencing the way, change the focus away leaving behind the school building and coming to do sports, eat or read a book. Actual volumes, however, could not become the answers, they could not become to be an integrated bloc. The space between them must band them together to give a complete character, followed by the part-built and connect everything to each other, gain mobility system common to all three. The solution became a principle belts - belt bound outdoors, belt inner freedom (hall, path to the target classroom, a room) and the target belt in the form of classrooms, gym and multipurpose halls. Cerda Plan for unique compared to other rectangular nets are the squares that are created with cutting off corner of the block. Project in such an urban network should respond to this. What is the city block and cut off the corner? In a project for me is not a barrier to good regular layout, but instead of entering the city and its principles into the project and school responses to these special places. In all four corners is resulting in an open hall houses all over the floor, becoming an indoor view schools in cities and towns for school. The system is one exception, it is an existing church, which has not an ambitions to become something special and unusual, but is part of the whole. Each object has its own ledge. This has become a symbol of an element that turns the house imide to the courtyard and other buildings. It connects the building and the downstream area, it gives him character building, sport connects with an outdoor playground, building a library with a place for rest and home school with a place with trees. All three ledges are the same height, thus uniting the whole school, the whole block. Facades are open underneath, glazed, thus having a different character than the rest.
157

Contrôles structuraux en 3 dimensions de la sédimentation turbiditique dans les chaînes plissées : exemple des Grès d’Annot (SE de la France) / 3D structural controls of turbidite sedimentation into fold and thrust belts : example of the Annot Sandstones (SE France)

Salles, Lise 04 June 2010 (has links)
Les Grès d’Annot préservés dans les chaînes subalpines méridionales sont des turbidites riches en sable déposées dans le basin d’avant pays alpin durant l’Eocène supérieur et l’Oligocène inférieur. La sédimentologie et la stratigraphie de ce système turbiditique ont déjà été étudiées, mais le contexte structural reste mal connu. Cette thèse est consacrée à l’étude tectonique des Grès d’Annot, combinant un travail de terrain et l’utilisation d’outils de modélisation géométrique en 3D (gOcad) et cinématique (Trishear), centrés sur les sous-bassins d’Annot, du Grand Coyer et de Sanguinière. L’objectif est d’étudier l’héritage et l’évolution structural du bassin turbiditique et de le replacer dans le contexte régional du SE de la France. Les résultats indiquent que le remplissage du bassin périalpin précoce (Eocène et Oligocène) est bien plus complexe qu’une simple migration de la sédimentation (Grès d’Annot) et de la déformation vers l’avant pays. Ils révèlent des interactions entre tectonique et sédimentation à différentes échelles. A l’échelle de l’avant-pays, une coupe équilibrée illustre le contrôle primordial de la marge passive salifère préexistante sur la structure de la chaîne plissée. Le sel triasique constitue un décollement basal régional, qui de par sa faiblesse, a accommodé une déformation alpine précoce d’une large zone de l’avant-pays dès l’Éocène moyen et supérieur. Les variations de stratigraphie mécanique des séries mésozoïques sont à l’origine d’un changement de style structural : lors de la compression, plusieurs niveaux de décollement actifs se développent dans la partie orientale où les séries sont plus argileuses et plus fines. Ceci induit, en surface, une géométrie de bassin complexe avec des plis de longueurs d’ondes différentes et des migrations de charnière au cours de la sédimentation turbiditique. L’héritage structural du bassin d’avant-pays, jusqu’alors sous-estimé, est le résultat de l’ouverture de la Téthys alpine et d’une déformation précoce régionale exprimée par des plis d’axe E-W qui débute dès le Crétacé supérieur et s’accentue durant l’Éocène moyen. Des résultats préliminaires de thermochronologie (datations U-Th/He sur zircons détritiques de grès moyens à grossiers ou de granodiorites présentes dans les coulées de débris du dépocentre de Sanguinière) suggèrent une exhumation des reliefs à l’origine du matériel détritique liée à cette déformation crétacée. L’étude structurale détaillée de la série des Grès d’Annot et de son substratum dans les sous-bassins d’Annot et du Grand Coyer permet de définir en 3D les connections entre les dépocentres et de proposer une évolution structurale de ceux-ci à l’échelle du bassin. Les paléocourants montrent un parallélisme avec la direction des plis majeurs, indiquant un confinement alors que des directions divergentes à proximité des structures tectoniques plus mineures ou transverses suggèrent que ces dernières interagissent avec les écoulements. Les turbidites se déposent parallèlement dans plusieurs synclinaux alpins, actifs en alternance ou en même temps. A l’échelle des dépocentres, la modélisation géométrique 3D du dépocentre d’Annot en utilisant gOcad permet d’identifier les structures héritées et de démontrer la contemporanéité du plissement alpin et des dépôts turbiditiques. La migration de l’onlap des dépôts de grès et la variation des pendages à l’intérieur des membres turbiditiques sont associées à une migration du dépocentre. Cette géométrie est liée à une migration de la charnière synclinale qui favorise une tendance des dépôts à migrer latéralement plutôt qu’à s’empiler.D’un point de vue sédimentologique et stratigraphique, les Grès d’Annot sont connus pour être un bon analogue des réservoirs des grands fonds de type « riches en sable », situés sur les marges passives en aval de deltas. / The Annot Sandstone, exposed in the southern sub-alpine chains, consists of sand-rich turbidites deposited in the Tertiary Alpine foreland basin (Upper Eocene – Lower Oligocene Annot Sandstone basin). While the sedimentology and stratigraphy of this turbidite system have been largely described and discussed, its structural framework remains unconstrained. This thesis presents a study of the tectonics of the Annot Sandstone basin based on field surveys and 3D geometrical (gOcad) and kinematic modelling (Trishear), focusing in particular on the Annot, Grand Coyer and Sanguinière sub-basins. Objectives were to determine the structural evolution of the sub-basins, including the role of inherited features, and to use these data to better constrain the alpine tectonic history of SE France.Infill of the early alpine foreland basin is more complex than a simple foreland migration of sedimentation and deformation. Results reveal complex interactions of tectonics and sedimentation at different scales during deposition of the Annot Sandstone.•At the foreland scale, a balanced cross-section illustrates the critical control by the pre-existing salt-based passive margin architecture on the structure of the fold and thrust belt. Triassic evaporates regionally acted as a weak basal detachment, accommodating an early alpine deformation phase of the whole foreland from the Middle to Upper Eocene. Variations in mechanical stratigraphy within the Mesozoic sediments generated a change in structural style. For example, the eastern region is characterized by a thinner, shalier Mesozoic succession, leading to several active detachments during alpine compression. Multiple fold wavelengths and synsedimentary rolling hinges generated by these active detachments led to complex depocentres. The previously under-estimated structural heritage of the foreland basin derived from rifting and spreading of the Alpine Tethys and from an early regional deformation responsible for E-W trending folds, which began in the Late Cretaceous and increased during the Middle Eocene. Preliminary thermochronology results (U-Th/He datings on detrital zircons of medium to coarse sandstone blocks and granodiorite blocks from debris flows of the Sanguiniere depocentre) suggest an exhumation of source areas during this Cretaceous deformation.•A detailed study of structures within the Annot and Grand Coyer sub-basins and their Cretaceous substrate revealed connected depocentres evolving in 3D at the basin scale. Paleocurrent directions are mainly parallel to the main alpine fold axes recording structural confinement, while some diverging directions indicate flow interaction with minor or oblique tectonic features. Turbidites were deposited along the axis into several alpine synclines, which were simultaneously or successively active.•Concerning the depocentre infill, 3D geometrical modelling of the Annot depocentre (using gOcad) was used to identify inherited structures and to constrain alpine fold activity during turbidite deposition. The onlap migration and the specific stacking and dip pattern within turbidite members (laterally rather than vertically stacked deposits) record depocentre migration linked with a rolling synclinal hinge. Due to its sedimentology and its stratigraphy, the Annot Sandstone is well-known as an analogue for sand-rich reservoirs deposited at delta toes in deep-water passive margins. This study reveals that, structurally, it is also a good example of axially-sourced turbidite depocentres developed on a multi-detachement fold and thrust belt
158

Autosalon / Autosalon

Bajer, Radim January 2015 (has links)
This master thesis is focused on elaboration of project documentation for constructing autosalon in Žďár nad Sázavou. Project and appendix are processed by current applicable laws, regulations and standarts. Designed object is situated on plat #6167/2. Both plat sis parts of cadastral area of Žďár nad Sázavou. There are all needed engineering netwoeks nearby. Object is divided on two functional parts, which are operationally and constructionally connected. First part is exhibition and representatice hall, which are capacity of 7 exhibited vehicles. Other partis formed by administrative facilities for staff including sanitary facilities for both staff and visitors. Second part is service for personal and light commercial vehicles with four working stations. Construction is designed reinforced concrete columnar structural system. Plan dimension autosalon is 31,06x22,6m. Plan dimension autoservise is 30,74x18,84m. The cladding autosalon is designed of ceramic tile 250mm. The cladding autoservis is designed of sandwich panel. Roof of building accross the surface is flat roof. Establishment of the object is a combination of footings and foundation belts. Cladding of exhibition hal lis more than 50% glazed. Parts of autosalon and autoservise are designed as sigle storey objects, while administrative part is designed as a two.
159

Autosalon / Motorshow

Bár, Radek January 2014 (has links)
This master thesis is focused on elaboration of project documentation for constructing autosalon in Kopřivnice. Project and appendix are processed by current applicable laws, regulations and standarts. Designed object is situated on plat #419/2 and partly on plat #419/27. Both plats are parts of cadastral area of Kopřivnice. There are all needed engineering networks nearby. Object is divided on three functional parts, which are operationally and constructionally connected. First part is exhibition and representative hall, with capacity of 11 exhibited vehicles. Second part is formed by administrative facilities for staff including sanitary facilities for both staff and visitors. Third part is service for personal and light commercial vehicles with three working stations. Construction is designed partially reinforced concrete columnar structural system and partially of brick longitudinal structural system. The biggest plan dimension of building is 34.3x35.15m. The cladding is designed of sandwich blocks LIVETHERM tl.400mm. Roof of building accross the surface is flat roof with several height levels. Establishment of the object is a combination of footings and foundation belts. Cladding of exhibition hall is more than 50% glazed. Parts of service and autosalon are designed as sigle storey objects, while administrative part is designed as a two.
160

Papers and related collections of James A. Van Allen,

Van Allen, James Alfred, Unknown Date (has links)
Includes Van Allen thesis (M.S.)--University of Iowa, 1936, and thesis (Ph.D.)--University of Iowa, 1939.

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