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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.
31

Dynamique et échanges sédimentaires en rade de Brest impactés par l'invasion de crépidules / Dynamic and exchanges of sediments in the bay of Brest impacted by the invasion of slipper limpets

Beudin, Alexis 12 December 2014 (has links)
Cette thèse est une contribution à l’étude de la dynamique sédimentaire dans l’écosystème de la rade de Brest. Elle a pour objectif de décrire, par la simulation numérique et l’observation in situ, le mouvement des masses d’eau et de sédiments sous l’influence de la marée à l’échelle de la rade, et l’impact de la distribution spatiale actuelle des populations de crépidules sur le transport de sédiments en suspension et l’évolution des fonds. Un modèle bidimensionnel horizontal (2DH) est mis en œuvre à partir du code TELEMAC. Il intègre la variabilité spatiale du substrat, et rend compte de la présence physique (macro-rugosité, partition de la contrainte de cisaillement) et de l’activité biologique (filtration de l’eau chargée de particules en suspension, production de biodépôts) des crépidules. Les mesures de hauteur d’eau, de vitesse du courant, et de vitesse de frottement valident de façon satisfaisante les choix de paramétrisation du modèle hydrodynamique. Les mesures de concentration de matière en suspension en rade de Brest sont sporadiques, et leur analyse est compliquée. Le modèle sédimentaire constitue un outil de compréhension. Il informe de l’évolution temporelle de la contribution de différents types de sédiments et de leur origine aux concentrations locales de sédiments en suspension et déposés. Il permet de suivre le cheminement des sédiments principalement en suspension, de quantifier les échanges entre les sous-bassins de la rade et avec le fond. L’introduction sur le fond des colonies de crépidules, sous forme de chaînes assimilées à des cylindres, induit une diminution de la vitesse du courant à l’aplomb et dans leur sillage, compensée par une augmentation en périphérie, entraînant une modification globale des zones d’érosion et de dépôt de sédiments. Localement, les macro-rugosités ont un effet antagoniste selon leur répartition: des densités moyennes augmentent le frottement de peau et les remises en suspension, tandis que des densités élevées induisent un masquage des sédiments sur le fond duquel résulte une accrétion. Par comparaison à leur impact hydrodynamique, l’activité biologique des crépidules joue un rôle secondaire sur la dynamique sédimentaire. / This thesis is a contribution to the study of sediment dynamic in the ecosystem of the bay of Brest. It aims at describing, by numerical simulations and field observations, the movement of water and sediments in the bay under tidal forcing, and the impact of the present spatial distribution of slipper limpets on suspended sediment transport and bed evolution. A two-dimensional horizontal (2DH) model is implemented based on the TELEMAC numerical system. It integrates the spatial variability of bed sediments, accounts for the physical presence (macro-roughness, form drag - skin friction partitioning) and biological activity (filtration of water carrying suspended particles, production of biodeposit) of slipper limpets. Measurements of water level, mean flow velocity, and friction velocity satisfactorily validate the choice of parameters in the hydrodynamic model. Measurements of suspended matter concentration in the bay of Brest are sporadic, and their analysis complicated. The sediment model stands as a tool for better understanding sedimentary processes. It informs the temporal evolution of the contribution of different types of sediment, and their origin, to local suspended and deposited sediment concentrations. It allows to follow the paths of sediment transport predominantly in suspension, and to quantify the exchanges of sediments between the sub-basins of the bay and with the bed. The introduction of slipper limpet colonies on the bed, in the form of chains assimilated as cylinders, induces decreasing flow velocity above and in their wake, compensated by increasing flow velocity on the outskirts, which globally modify the patterns of sediment erosion and deposition in the bay. Locally, the macro-roughness elements have an antagonist effect depending on their distribution: medium densities increase skin friction and erosion flux, whereas high densities shelter bed sediments from which results accretion. By comparison to their hydrodynamic impact, the biological activity plays a secondary role on sediment dynamic.
32

Monolitický vícepodlažní stěnový objekt / Monolithic multi-storey wall building

Vymazal, Jakub January 2015 (has links)
Final thesis with tittle: "Monolithic multi-storey wall building" is processeed as a project documentation according to valid assesment. The object is located in the city of Boskovice, 35 Hybešova street. Its ground plan dimensions are 52,8m x 12,5m. Total height of object is 22,3m including roof-wall, measured from the level of base chink. There are enclosed balconies on the south direction. Movement between floors is ensured by 2-flighted stairs. Object is It is made of reinforced concrete. It is designed as 6-floor bulding with a flat roof. The main supporting construction is created by system of walls and reciprocally asigned ceilings, which are sticked together. Walls are designed as pillars. The building is assigned to a belt bases. Module dimensions are 8,7m in longitudinal direction and 5,2m in transversal direction. Height dimension is 3,0m. The thesis is dealing with the 1st upper floor.
33

Srovnání vybraných způsobů ocenění pro nemovitost typu rekreační chata a chalupa užívaná i k trvalému bydlení v lokalitě Města Brna / Comparison of Selected Methods of Valuation of Holiday Cottage-type Real Estate Used also for Permanent Housing in the Brno City Area

Šmíd, Jiří Unknown Date (has links)
My thesis work will go in theoretical part about explanation of basic terms, that are commonly used in valuation of real estates like recreation cottages, which are used for permanent living. Way of preparation for measuring and imporant tools used during measuring proces are also described here. Individual ways of valuation are used in practical part. Result will be valorization of used methods and evaluation of the best method for each locality and type of real estate.
34

Räddningsarbeten i slutna utrymmen : En studie om hur övningar ombord förbereder besättningen för evakuering i slutna utrymmen / Rescue work in enclosed spaces : A study on how drills on board prepare the crew for evacuation in confined spaces

Blomquist, David, Larsson, Fredrik January 2020 (has links)
Arbeten i slutna utrymmen är ett vanligt förekommande moment ombord på fartyg. Olyckor i samband med slutna utrymmen är tyvärr också vanligt förekommande. I många olycksfall så kan även de som ska hjälpa en nödställd i ett slutet utrymme drabbas av skador eller att dem i värsta fall mister livet. Detta resulterar i fler skadade eller omkomna än vad nödsituationen först hade. Den här studien har genom en kvalitativ forskningsmetod intervjuat sex respondenter med en semistrukturerad intervju. Respondenterna bestod av sjökaptensstudenter från Sjöbefälshögskolorna i Sverige. Arbetet undersökte hur övningarna ombord på fartygen förbereder besättningen på evakuering ur slutet utrymme. Studien fann att det upplevs övas för lite inom området slutna utrymmen och att osäkerheten kring situationerna som kan uppstå är hög. Många respondenter upplevde att man inte kunde rädda någon på en tillräckligt snabb tid och att evakueringar ur slutna utrymmen är ett väldigt svårt moment. Studiens resultat tyder på en kunskapsbrist inom situationerna kring evakuering ur slutet utrymme. / Work in enclosed spaces is a common occurrence on board ships. Unfortunately, accidents associated with confined spaces are also common. In many accidents, even those who intend to help a distressed person in an enclosed space can suffer injuries or in the worst case lose their lives. This results in more people injured or killed than the emergency first had. This study has through a qualitative reaserch method, interviwed six respondents with a semi-structured interview. The respondents consisted of naval officer students from the Swedish Naval Officer Universities in Sweden. The study investigated how the exercises aboard the ships prepare the crew for evacuation from enclosed spaces. The study found that in the respondent’s experience that it is practiced too seldomly and because of that it may arise some uncertainty in those situations. Many respondents felt that they could not save anyone in a fast enough time and that evacuations from confined spaces are a very difficult task.The study’s result indicates a lack of knowledge in the situation of evacuation from enclosed spaces.
35

Otázky struktury osídlení severovýchodní části středních Čech ve starší době bronzové na příkladu opevněné lokality Brandýs nad Labem-Vrábí / Settlement structure of the Early Bronze Age in the northeast part of central Bohemia - the case study of fortified settlement in Brandýs nad Labem-Vrábí

Langová, Michaela January 2019 (has links)
Between 2007 and 2016, there was a rescue archeological research done by the Institute of Archaeology of the CAS in the locality of Brandýs nad Labem-Vrábí at the site "U Vodojemu", where, above other, a large settlement from the Early Bronze Age was uncovered. Based on the ceramics, it is possible to classify it chronologically as the early period of the Únětice culture, typologically then, it is possible to associate the ceramics found with the post-classical phase of the Únětice culture. The discovery of the U-shaped ditch adjacent to the ground edge of the Hrušovský stream indicates that the settlement was fortified for a certain time, approximately at the beginning of the 2nd millennium BC. Based on the nature of the ditch filling, of the ceramic findings with analogies in the beginning of the tumulus culture, as well as of the carbon dating, it is obvious that the settlement served further on after the downfall of this fortification, too, and thus for another 100 years at least. In the context of another very numerous, contemporaneous findings in the cadaster of Brandýs nad Labem, it is visible that the site "U Vodojemu" used to be a part of a large settlement agglomeration. A detailed mapping of the Early Bronze Age findings from the district of the north-east part of Central Bohemia has...
36

The utilisation of satellite images for the detection of elephant induced vegetation change patterns

Simms, Chenay 02 1900 (has links)
South Africa’s growing elephant populations are concentrated in relatively small enclosed protected areas resulting in the over utilisation of the available food sources. Elephants and other herbivores as well as other natural disturbances such as fires and droughts play an important role in maintaining savannah environments. When these disturbances become too concentrated in a particular area the vegetation composition may be negatively affected. Excessive damage to the vegetation would result from exceeding the capacity of a protected area to provide food resources. The effect of the 120 elephants on the vegetation of Welgevonden Private Game Reserve, is not known. The rugged terrain of this reserve makes it a difficult, time consuming and labour intensive exercise to conduct ground studies. Satellite images can be used as a monitoring tool for vegetation change and improve the quantity and quality of environmental data to be collected significantly, allowing more informed management decision-making. This study evaluated the use of satellite imagery for monitoring elephant induced vegetation change on Welgevonden Private Game Reserve. The LANDSAT Thematic Mapper multispectral images, acquired at two yearly intervals from 1993 until 2007 were used. However, no suitable images were available for the years 1997, 2001 and 2003. A series of vegetation change maps was produced and the distribution of water sources and fire occurrences mapped. The areas of change were then correlated with the spatial distribution of water points and fire occurances, with uncorrelated areas of change. This was analysed using large animal population trends, weather data and management practices. On the visual comparison of the vegetation maps, it was seen that over this time period there was some decrease and thinning of woodland, but the most notable change was the increase of open woodland and decrease in grasslands. Using only the digital change detection for the period 1993 to 2007, a general increase in vegetation cover is seen. But this generalisation is misleading, since comparing the digital change detection to the vegetation maps indicates that while vegetation cover may have increased, significant changes occurred in the vegetation types. Most of the areas of significant change that were identified showed a strong positive correlation with burnt areas. The distribution of the water sources could not be directly linked to the vegetation change although rainfall fluctuations seemed to have accelerated vegetation changes. Years with high game counts, such as 1999, also coincide with very low rainfall making it difficult to differentiate between the effects of heavy utilisation of vegetation and low rainfall. Furthermore, many of the initial vegetation changes could be the result of land use changes due to the introduction of browsers, selective grazers and elephants that allow for more natural utilisation of the vegetation. Remote sensing makes it possible to successfully track changes in vegetation and identify areas of potential elephant induced vegetation change. Vegetation changes caused by disturbances, such as fire and anthropogenic activities, can be accounted for but it is not possible to conclude with a high level of certainty that the further changes seen are solely a result of elephant damage. Further work is required to reliably isolate elephant induced vegetation changes, as well as to establish the effects these changes have on the ecosystem as a whole. / Environmental Sciences / (M. Sc. (Environmetal Sciences))
37

La Mer caspienne et le droit international / The Caspian sea and the international law

Guliyev, Khagani 08 February 2013 (has links)
La mer Caspienne qui est devenue l’objet du droit international depuis le XVIIIe siècle n’a jamais connu un statut juridique précis. Cet espace dont la nature aquatique fait l’objet de divergence était dominé par l’URSS jusqu’en 1991. Cependant, à la suite de la disparition de l’URSS, la mer Caspienne - désormais entourée de cinq États riverains (Azerbaïdjan, Iran,Kazakhstan, Russie et Turkménistan) – a fait sa réapparition sur la scène internationale, surtout en raison de ses riches ressources naturelles. C’est précisément dans ces conditions que la question de la situation juridique de la mer Caspienne au regard du droit international s’est posée à la fin du XXe siècle. Il convient donc de former un régime juridique de la mer Caspienne adéquat et durable à long terme et de trouver des solutions pour le règlement desdifférends juridiques entre les États caspiens. / The Caspian Sea which has become the object of international law since the eighteenth century has never had a clear legal status. This space of which the aquatic nature is not defined was dominated by the Soviet Union until 1991. However, following the collapse of the USSR, the Caspian Sea - now surrounded by five littoral States (Azerbaijan, Iran, Kazakhstan, Russia and Turkmenistan) - has re-emerged on the international scene, especially because of its rich natural resources. It is precisely in these circumstances that the question of legal status of the Caspian Sea under international law arose in the late twentieth century. Therefore, it is necessary to form an adequate and sustainable long-term legal regime of theCaspian Sea and to find solutions for the settlement of legal disputes between the Caspian States.
38

Dynamická karta rozpočtového ukazatele rodinného domu / Dynamic card of cost indicator of house

Vrbka, Marek January 2016 (has links)
This master thesis describes a detached house, requirements for the detached house, price, technical-economic index and card of cost indicator. The author performed an analysis of selected houses and itemized budgets of selected houses. Different shapes, technologies and solutions of materials are included in the analysis. The author, from the analysis, inferred the behavior of technical-economic index (TEI) of detached houses. The author described behavior in the particular and sub models. The author suggested methodology of calculation of the price data, the spatial data and the structure of price TEICF2 (technical-economic index, complex formula, version 2) of planned detached house. The author founded his methodology on particular and sub models. The principle of methodology TEICF2 consists in the analogy of the planned detached house with the model with same parameters. The author implemented TEICF2 into application dyCBI. Application dyCBI is working on Microsoft Excel.
39

The utilisation of satellite images for the detection of elephant induced vegetation change patterns

Simms, Chenay 02 1900 (has links)
South Africa’s growing elephant populations are concentrated in relatively small enclosed protected areas resulting in the over utilisation of the available food sources. Elephants and other herbivores as well as other natural disturbances such as fires and droughts play an important role in maintaining savannah environments. When these disturbances become too concentrated in a particular area the vegetation composition may be negatively affected. Excessive damage to the vegetation would result from exceeding the capacity of a protected area to provide food resources. The effect of the 120 elephants on the vegetation of Welgevonden Private Game Reserve, is not known. The rugged terrain of this reserve makes it a difficult, time consuming and labour intensive exercise to conduct ground studies. Satellite images can be used as a monitoring tool for vegetation change and improve the quantity and quality of environmental data to be collected significantly, allowing more informed management decision-making. This study evaluated the use of satellite imagery for monitoring elephant induced vegetation change on Welgevonden Private Game Reserve. The LANDSAT Thematic Mapper multispectral images, acquired at two yearly intervals from 1993 until 2007 were used. However, no suitable images were available for the years 1997, 2001 and 2003. A series of vegetation change maps was produced and the distribution of water sources and fire occurrences mapped. The areas of change were then correlated with the spatial distribution of water points and fire occurances, with uncorrelated areas of change. This was analysed using large animal population trends, weather data and management practices. On the visual comparison of the vegetation maps, it was seen that over this time period there was some decrease and thinning of woodland, but the most notable change was the increase of open woodland and decrease in grasslands. Using only the digital change detection for the period 1993 to 2007, a general increase in vegetation cover is seen. But this generalisation is misleading, since comparing the digital change detection to the vegetation maps indicates that while vegetation cover may have increased, significant changes occurred in the vegetation types. Most of the areas of significant change that were identified showed a strong positive correlation with burnt areas. The distribution of the water sources could not be directly linked to the vegetation change although rainfall fluctuations seemed to have accelerated vegetation changes. Years with high game counts, such as 1999, also coincide with very low rainfall making it difficult to differentiate between the effects of heavy utilisation of vegetation and low rainfall. Furthermore, many of the initial vegetation changes could be the result of land use changes due to the introduction of browsers, selective grazers and elephants that allow for more natural utilisation of the vegetation. Remote sensing makes it possible to successfully track changes in vegetation and identify areas of potential elephant induced vegetation change. Vegetation changes caused by disturbances, such as fire and anthropogenic activities, can be accounted for but it is not possible to conclude with a high level of certainty that the further changes seen are solely a result of elephant damage. Further work is required to reliably isolate elephant induced vegetation changes, as well as to establish the effects these changes have on the ecosystem as a whole. / Environmental Sciences / (M. Sc. (Environmetal Sciences))
40

Modélisation numérique des phénomènes aérothermiques dans les machines électriques en vue d’optimisation de leur conception : application aux machines électriques des véhicules hybrides et électriques / Numerical modeling of the aerothermal behavior inside electrical machines in order to optimize their design : applications for automotive vehicles

Ben Nachouane, Ayoub 21 March 2017 (has links)
Implanter une machine électrique dans un véhicule hybride pose avant tout des problèmes d’encombrement. Sous-dimensionner la machine semble légitime compte tenu de l’usage qui en est fait sur véhicule. Par contre, cela suppose que les aspects thermiques soient pris en compte non seulement lors de l’utilisation, mais aussi lors de la conception de la machine. Le phénomène majeur limitant la densité de puissance massique des machines électriques est l’échauffement interne des bobines et des aimants. La modélisation thermique de la machine est complexe compte tenu de la diversité des sources de chaleur et de la coexistence de différents modes de transferts thermiques : conduction dans la matière, convection avec l’eau de refroidissement, conduction, convection et rayonnement dans l’entrefer. En termes de géométrie, si une première approche peut être réalisée en ne considérant que des flux de chaleur radiaux, la composante axiale doit nécessairement être prise en compte dès lors qu’on veut tenir compte aussi des extrémités de machine, et notamment de la chaleur produite par les roulements et les têtes de bobines. Ainsi pour pouvoir analyser pertinemment les transferts thermiques dans la machine, des méthodes numériques de type CFD ont été utilisées pour caractériser le transfert thermique par convection. La caractérisation des échanges thermiques par convection naturelle et forcée a été réalisée à l’intérieur d’une machine synchrone à aimants permanents internes (MAPI). Des relations empiriques ont été proposées afin de prendre en compte le couplage entre la thermique et l’aérodynamique dans les cavités des machines électriques totalement fermées. Afin de valider la pertinence des modèles numériques dans le cadre de ce travail, des mesures thermiques à l’aide des moyens d’essais de l’UTC ont été réalisées. Les résultats de cette étude sont utilisés pour construire des circuits thermiques équivalents qui prennent en compte les phénomènes thermiques complexes dans les machines électriques fermées utilisées dans les véhicules hybrides et électriques. Ces recommandations de conception permettront l’optimisation de l’effort investi pour le refroidissement de la machine électrique dans ses différentes phases de fonctionnement. / The integration of an electrical machine into modern hybrid vehicles is associated with new technical constraints such as the integrability into small volume without losing certainly in performance. Therefore, the development of compacter electrical machines is a well-founded argument for car manufacturers as well as electrical machine designers. On the other hand, this finding assumes that the thermal aspects are undertaken not only during the operation of the electrical machine, but also during the design process. The internal heat generated in different areas impacts strongly the power density and the magnet health which deeply reduce the electrical machine reliability. Heat transfer modeling inside electrical machines is a tricky task because of the strong coupling between the different physics governing their operations. Indeed, the generated losses spread inside the electrical machine through three heat transfer modes which are: conduction (heat diffusion), convection(heat transport) and radiation (heat scattering). In terms of geometry, if a first approach can be carried out by considering only radial heat fluxes, the axially-transferred heat must be undertaken when it is also necessary to consider end caps effects, and particularly the heat released by the bearings. In order to carry out relevantly the thermal analysis of a permanent magnets synchronous machine, CFD based methods are used to characterize the convective heat transfer inside this machine over a large operating range. Both natural and forced convection are analyzed and the corresponding heat transfer coefficients are numerically-estimated. Empirical equations are proposed in order to take into account the coupling between thermal and fluid dynamics inside the cavities of the studied totally-enclosed machine. These correlations are integrated then into a detailed and reduced thermal network. Experimental tests are carried out using a test bench in order to measure temperature distribution in different areas of the electrical machine. Afterward, a comparison between estimated and measured temperatures shows that the results of the numerically-enhanced thermal network are in a good agreement with measurements. Thus, the proposed recommendations based on CFD modeling allow the convective heat transfer to be characterize quickly and precisely. These correlations are useful for upcoming studies dealing with convection inside automotive electrical machines as well as high speed electrical machines.

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