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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.
81

Rekonstrukce železničního tunelu / Reconstruction of the railway tunnel

Nekl, Jiří January 2013 (has links)
The diploma thesis engages in the reconstruction of railway tunnel Domasovsky that is situated at the track section Olomouc – Krnov. It illustrates the current state of the construction and the geotechnical conditons of the area of interest, it also presents the potencial solutions. The design is verified by stuructural analysis, the design documentation and technical report are also enclosed.
82

Tunel na trase rychlé železnice / The tunnel on the fast railway

Závacký, Martin January 2016 (has links)
The theme of this thesis is to create a conceptual study of the tunnel on high speed railway. Selection of suitable cross section and tunnelling method with considering of geological conditions of the site. Design of primary support and technological process of construction.
83

Microorganisms, flight, reproduction, and predation in birds / Micro-organismes, vol, reproduction et prédation chez les oiseaux

Al rubaiee, Zaid 28 April 2017 (has links)
Les coûts de remise en forme que les macro et micro parasites imposent aux hôtes peuvent s'expliquer par trois facteurs principaux : (1) Les hôtes utilisent des réponses immunitaires contre les parasites pour prévenir ou contrôler l'infection. Les réponses immunitaires nécessitent de l'énergie et des nutriments pour produire et / ou activer les cellules immunitaires et les immunoglobulines, ce qui est coûteux, provoquant des compromis avec d'autres processus physiologiques comme la croissance ou la reproduction. (2) Le taux métabolique de l'hôte peut être augmenté parce que les dommages aux tissus et la réparation ultérieure de l'infection causée par le parasite peuvent être coûteux. (3) Le taux métabolique des hôtes peut augmenter et donc augmenter également leurs besoins en ressources. La compétition entre macro-parasites et hôtes peut priver les ressources de l'hôte. Les coûts de remise en forme que les macro et micro parasites imposent aux hôtes peuvent s'expliquer par trois facteurs principaux : (1) Les hôtes utilisent des réponses immunitaires contre les parasites pour prévenir ou contrôler l'infection. Les réponses immunitaires nécessitent de l'énergie et des nutriments pour produire et / ou activer les cellules immunitaires et les immunoglobulines, ce qui est coûteux, provoquant des compromis avec d'autres processus physiologiques comme la croissance ou la reproduction. (2) Le taux métabolique de l'hôte peut être augmenté parce que les dommages aux tissus et la réparation ultérieure de l'infection causée par le parasite peuvent être coûteux. (3) Le taux métabolique des hôtes peut augmenter et donc augmenter également leurs besoins en ressources. La compétition entre macro-parasites et hôtes peut priver les ressources de l'hôte. / The fitness costs that macro- and micro-parasites impose on hosts can be explained by three main factors: (1) Hosts use immune responses against parasites to prevent or control infection. Immune responses require energy and nutrients to produce and/or activate immune cells and immunoglobulins, and that is costly, causing trade-offs against other physiological processes like growth or reproduction. (2) The host’s metabolic rate can be increased because tissue damage and subsequent repair from the infection caused by parasite may be costly. (3) The metabolic rate of hosts may increase and hence also increase their resource requirements. Competition between macroparasites and hosts may deprive resources of host. Birds are hosts for many symbionts, some of them parasitic, that could decrease the fitness of their hosts. There is a huge diversity in potential parasites carried in a bird’s plumage and some can cause infection. Nest lining feathers are chosen and transported by adult birds including barn swallows Hirundo rustica to their nests, implying that any heterogeneity in abundance and diversity of microorganisms on feathers in nests must arise from feather preferences. we found that the effects of microorganisms on the behavior of birds may be a combination of positive and negative effects. There may be positive effects of antimicrobial activity on birds through the process of bacterial interference, consisting of certain bacteria impeding the establishment of competing bacterial strains by producing antibiotic substances. Meanwhile, the negative effects may imply that pathogenic or/and feather-degrading microorganisms may reduce fitness components of their hosts. These effects of microorganisms and hence the microbiome can be affected by the behavior of bird hosts.
84

Vliv vnějších podmínek na inkubaci vajec u čejek rodu Vanellus v temperátním a subtropickém klimatu / Influence of external conditions on egg incubation in lapwings (genus Vanellus) in temperate and subtropical climate

Pešková, Lucie January 2020 (has links)
During incubation, most birds require the presence of at least one parent to ensure suitable incubation conditions for embryo development. The main factors that affect the development of the embryo are temperature, humidity and egg turning. In this work, incubation conditions were investigated in two biparental Lapwing species (genus Vanellus), the Northern Lapwing (Vanellus vanellus), which faces the risk of egg cooling in temperate areas, and the Red-wattled Lapwing (Vanellus indicus), which faces the risk of egg overheating in the subtropics. A laboratory experiment testing the thermal properties of the Red-wattled Lapwing nest lining showed that it selects lining material that slows down temperature growth during egg heating, thus ensuring suitable thermal conditions during parental absence at high ambient temperatures. Temperature and egg turning during incubation were recorded by an artificial egg with a built-in sensors placed in the nests of both target species; data collected by the sensors were stored by a base-station located nearby. The average egg temperature was 32.5 řC for the Northern Lapwing, and 35.0 řC for the Red-wattled Lapwing. Egg temperature in both species fluctuated significantly, affected by many factors. Egg temperature increased with increasing ambient temperature, it...
85

Life cycle assessment comparison of CIPP lining and traditional pipe replacement / En jämförande livscykelanalys av CIPP-lining och traditionellt stambyte

Berglund, Daniel January 2015 (has links)
During the so-called “Miljonprogrammet”, over a million homes were built in Stockholm. As the buildings mature, parts of the buildings reach their technical life times and it is time to renovate them. At a time when the environmental impact of humans is a hot topic, it is appropriate to take the environment into account when deciding upon which restoration method to use. The sewage pipes are one of the important building parts in need of repair. This can be achieved by for example traditional pipe replacement or Cure-In-Place-Pipes (CIPP-lining).The goal of this study is to investigate and compare the environmental impact of traditional pipe replacement versus the use of the relining method CIPP lining by conducting a comparative life cycle assessment (LCA). The methods differ in the way that traditional pipe replacement demolishes the outer layers of the bathrooms and remove the old pipes to replace with new and restore the surface layers while CIPP-lining renovates the pipes from the inside with the use of a flexible liner.The purpose of the study has been to clarify the differences in environmental impacts of the different methods in a clear and easily understood way and thereby also simplify the decision-making process of property owners in need of renovation.With aid of the guidelines in ISO standards 14040 and 14044 a correct methodology has been used to ensure that the level of this work will be as high as possible. In combination with the software SimaPro specifically developed to handle the creation of various forms of life cycle assessments and the ISO standards a complex system been analyzed in detail.The results of the study show that CIPP-lining generally cause less environmental impacts than the traditional pipe replacement method. The analysis of 14 selected impact categories show that CIPP lining is preferable in 13 categories and that the traditional pipe replacement is preferable in 1 category. The sensitivity analysis show that the results change drastically depending on how much of the materials and energy used to demolish and reconstruct the outer layers of the bathroom one chooses to allocate to the new sewer pipes.The results show that the CIPP-lining results are dependent on the consumables and the liner assembly processes while the energy usage of the production process does not have a large impact on the results. For the traditional pipe replacement the results show that the consumable process is clearly the biggest impact while the piping production inflicts the least impact on the result.
86

Исследование стойкости футеровки «стальных» конвертеров АО «ЕВРАЗ НТМК» : магистерская диссертация / The studing of durability lining «steel» converters JSC «EVRAZ NTMK»

Лапинский, А. А., Lapinsky, A. A. January 2024 (has links)
В диссертации рассмотрены технология производства стали, мероприятия по уходу за футеровкой конвертеров и их виды, а также обзор механического оборудования конвертерного отделения КЦ №1 АО «ЕВРАЗ НТМК». Представлен расчет оптимальной стойкости футеровки конвертеров, выплавляющих сталь, также произведены расчеты, показывающие возможность оптимизации межремонтных сроков оборудования конвертерного отделения при максимальной загрузке. Практическая значимость исследования и направления развития заключаются в возможности применения мероприятий на любом металлургическом предприятии, эксплуатирующем кислородные конвертеры. / The dissertation examines steel production technology, measures for the care of converter linings and their types, as well as an overview of the mechanical equipment of the converter department of EVRAZ NTMK JSC. A calculation of the optimal durability of the lining of converters that smelt steel is presented; calculations have also been made showing the possibility of optimizing the turnaround time of the converter department equipment at maximum load. The practical significance of the research and directions of development lie in the possibility of applying the measures at any metallurgical enterprise operating oxygen converters.
87

Nové směry provádění hydroizolací dopravních podzemních staveb / New directions for waterproofing of underground transport

Čech, Tomáš January 2019 (has links)
This diploma thesis focuses on the implementation of waterproofing of underground constructions using an LLDPE membrane hinged on anchors. In the future, this method will replace the commonly used waterproofing system in Scandinavia with extruded polyethylene foam. This method of tunnel construction and waterproofing is compared with the NRTM method, often used in Central Europe. The thesis describes the installation of a waterproofing system, especially materials, accessories, welding devices and auxiliary installation equipment. The main focus of the thesis is to verify the reliability of the individual types of welds and to assess the waterproofing system in terms of implementation and environmental demands.
88

Nové směry provádění hydroizolací dopravních podzemních staveb / New directions for waterproofing of underground transport

Čech, Tomáš January 2019 (has links)
This diploma thesis focuses on the implementation of waterproofing of underground constructions using an LLDPE membrane hinged on anchors. In the future, this method will replace the commonly used waterproofing system in Scandinavia with extruded polyethylene foam. This method of tunnel construction and waterproofing is compared with the NRTM method, often used in Central Europe. The thesis describes the installation of a waterproofing system, especially materials, accessories, welding devices and auxiliary installation equipment. The main focus of the thesis is to verify the reliability of the individual types of welds and to assess the waterproofing system in terms of implementation and environmental demands.
89

Posouzení vlivu nového hlubinného základu na konstrukci primárního kolektorového tunelu / The impact assessment of a new deep foundation for the structure of the primary service tunnel

Lipka, Miroslav January 2012 (has links)
The purpose of the diploma thesis is assess the impact of piles on primary collector lining. Using a mathematical model has been calculated interaction between pile ond collector lining. The main task is to decide the length dependence of the pile deformations and internal forces that are the concrete lining of the collector.
90

Analýza působení termoplastových potrubí v zemním prostředí / Analysis of Thermoplastic Pipes in a Soil Environment

Ekr, Jan January 2019 (has links)
The doctoral thesis deals with an analysis of thermoplastics pipes in a soil environment, in particularly, pipes performed by using trenchless technologies. In the doctoral thesis, experiments of polyethylene pipes loaded by external hydrostatic pressure were performed. The aim of the experiments was to determine a behaviour and load-bearing capacity of the polyethylene pipes loaded by external hydrostatic pressure. For the experiments, a steel pressure chamber was designed and produced which allowed loading and observing a pipe during its loss of the stability. Mechanical properties of the pipe material were determined based on the tensile and bending tests. The series of detailed numerical analyses of the pipe experiments were performed. Various material models which take into account elastic, plastic and viscous behaviour of thermoplastic materials were used. In addition, series of standardized calculations of polyethylene pipes installed using trenchless technologies were performed. The aim was to create new design diagrams for practical assessment of these pipes placed in the partially deteriorated old pipes. In the case of the deteriorated old pipe, a numerical model for determination of design coefficients was created. These design coefficients were verified with standard values. Then, the results of the numerical model were compared with the results of the more complex numerical model which better take into account pipe-soil interaction of various soil types.

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