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Determination of the mechanical properties of materials used for 3D printing
Černý, Martin ; Sliwková, Petra (referee) ; Sedlák, Josef (advisor)
The thesis deals with the determination of mechanical properties of materials used for 3D printing (ABS, nylon and PLA). Standardized samples produced using a 3D printer using the Fused Deposition Modeling method were subsequently used for mechanical testing. The work is also extended to determine the mechanical properties of samples made by Soft Tooling. For the production of Soft Tooling samples, polyurethane resins SG 2000 and SG 145 were used. Individual materials were analyzed by mechanical tests (tensile test and hardness test). Surface integrity parameters have also been determined for 3D-printed materials. Parameters were selected from the individual tests (tensile strength, modulus of elasticity) ductility and hardness), which were subsequently statistically processed. The work is concluded by evaluating the results obtained, which were compared with the values given in material sheets.
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Analysis of escape routes in 3D building model
Halajová, Andrea ; Bartoněk, Dalibor (referee) ; Černý, Martin (advisor)
This diploma thesis is dealing about the Analysis of escape routes in 3D Building model. At first 3D BIM model, in format IFC, is extracted into the GIS software ArcGiS. From the model is created topology network, which representes the rooms and their connections. Based on this model is created the network analysis for building's escape routes. Results are 5 graphical representation of networks, web visualization and time required to exit from each room of the building.
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City information model based on a 3D data
Dolník, Michal ; Černý, Martin (referee) ; Volařík, Tomáš (advisor)
This diploma thesis deals with creation of data-oriented 3D city model. The aim is to show potential of 3D data in the field of 3D city models and to develop a methodology of conversion of 3D-data with no information to data oriented 3D city model. For this purpose has been chosen format CityGML, which is well-known in the field of 3D city models. This format allows us to store semantical, topological and visual information besides geometry. In terms of concept, thesis is divided into two parts. First part is focused on theory, where are mentioned 3D supported formats. Further I deal with categories of city models according to its usage in praxis and theory about structure of CityGML and its advantages. In second part, I deal with the process of data conversion and its processing. I used geometric data of city parts Líšeň and Nový Lískovec and energy data of some blocks of flats. In the end of thesis, I summarize all the results, possible usage and development of the model.
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The Role of Bi/Material Interface in Integrity of Layered Metal/Ceramic
Masini, Alessia ; Černý, Martin (referee) ; Bermejo, Raul (referee) ; Chlup, Zdeněk (advisor)
The present doctoral thesis summarises results of investigation focused on the characterisation of materials involved in Solid Oxide Cell technology. The main topic of investigation was the ceramic cell, also known as MEA. Particular attention was given to the role that bi-material interfaces, co-sintering effects and residual stresses play in the resulting mechanical response. The first main goal was to investigate the effects of the manufacturing process (i.e. layer by layer deposition) on the mechanical response; to enable this investigation, electrode layers were screen-printed one by one on the electrolyte support and experimental tests were performed after every layer deposition. The experimental activity started with the measurement of the elastic characteristics. Both elastic and shear moduli were measured via three different techniques at room and high temperature. Then, uniaxial and biaxial flexural strengths were determined via two loading configurations. The analysis of the elastic and fracture behaviours of the MEA revealed that the addition of layers to the electrolyte has a detrimental effect on the final mechanical response. Elastic characteristics and flexural strength of the electrolyte on the MEA level are sensibly reduced. The reasons behind the weakening effect can be ascribed to the presence and redistribution of residual stresses, changes in the crack initiation site, porosity of layers and pre-cracks formation in the electrode layers. Finally, the coefficients of thermal expansion were evaluated via dilatometry on bulk materials serving as inputs for finite elements analyses supporting experiments and results interpretation. The second most important goal was to assess the influence of operating conditions on the integrity of the MEA. Here interactions of ceramic–metal interfaces within the repetition unit operating at high temperatures and as well at both oxidative and reductive atmospheres were investigated. The elastic and fracture responses of MEA extracted from SOC stacks after several hours of service were analysed. Layer delamination and loss of mechanical strength were observed with increasing operational time. Moreover, SEM observations helped to detect significant microstructural changes of the electrodes (e.g. demixing, coarsening, elemental migration and depletion), which might be responsible for decreased electrochemical performances. All the materials presented in this work are part of SOC stacks produced and commercialised by Sunfire GmbH, which is one of the world leading companies in the field.
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GIS ANALYSIS IN BUILDING INFORMATION MODELS
Černý, Martin ; Kubíček,, Petr (referee) ; Vyhnálek,, Rudolf (referee) ; Bartoněk, Dalibor (referee) ; Pospíšil, Lubomil (advisor)
This dissertation thesis are concerned about the Geographic Information Systems (GIS) and spatial analyses inside of the Building Information Models (BIM). BIM and GIS are compared from different points of view like data organization, geometry types and modelling paradigms. Results of this comparisons are applied in the first case study where BIM data in IFC format are converted to the SHP format usable for spatial analyses in GIS. The results of the case study are evaluated and new approach for spatial analyses in BIM models is proposed based on the results. The new proposed approach is based on the semantic relations existing in the BIM models. Thesis are concluded with the future development which is in line with authors actual focus.
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Working out of methodology for creation of building information model
Nováková, Věra ; Černý, Martin (referee) ; Hanzl, Vlastimil (advisor)
This thesis is focused on creation of building information model (BIM) for existing buildings. The main objective of this work is to develop the methodology (workflow) for the creation of BIM model using selected geodetic methods, specifically for the modeling based on the existing documentation of the building, the modeling from the handheld distance meter and the modeling from point cloud acquired by the indoor mapping system. The aim of these workflows is to explore the suitability of these methods, to check the limits of each method and to point out the potential issues. Revit (version 2013 and 2014) was used as an authoring environment for creation of the models. Workflow for modeling based on the documentation of the building shows how to insert drawings into Revit and how to create a model based on these drawings. The workflow was developed based on experience with creation of model of an office building. The workflow for handheld laser distance meter describes how to work with rangefinder equipped with Bluetooth, which allows user to create a model onsite. The third part of this thesis deals with creation of BIM from pointcloud acquired by indoor mobile mapping system. The workflow describes data collection and point clouds processing directly in Revit using the ScanToBIM extension. The results of this work are methodical instructions for the methods described above and the comparison of these methods. Workflows contain recommended procedures and highlight common issues and mistakes. This should enable the readers of this thesis to choose the right method and avoid common mistakes.
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Working out of methodology for creation of building information mode
Sládková, Veronika ; Černý, Martin (referee) ; Hanzl, Vlastimil (advisor)
The subject of thesis was creation of methodic for building information modeling methods specified. The buildings were surveyed at first or projects drawing were provided. Processing of survey data and building information modeling was done in software Revit 2014 with program extensions. Subsequently chosen methods of creation were described and they were compared with each other. The result can use for selection the most appropriate method on the basis function and targeted funds.
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Habitat selection by dragonflies - effect of littoral and riparian vegetation
Bonková, Anita ; Černý, Martin (advisor) ; Waldhauser, Martin (referee)
Dragonflies form one of the important pillars of most aquatic ecosystems and play an important role in maintaining their balance. The main goal of this bachelor's thesis is to summarize current knowledge about the habitat preferences of members of the order Odonata, with a focus on the effect of littoral and riparian vegetation, which are critical components of aquatic biotopes and significantly influence the distribution, abundance and reproductive success of dragonflies. In my work, I focus on all developmental stages, from larvae to adults. These findings are important for the maintenance and revitalization of freshwater ecosystems, in which it is necessary to pay attention to the composition of littoral and riparian vegetation to support the diverse needs of this unique insect order. Key words: habitat preference, dragonflies, Odonata, riparian vegetation, littoral vegetation
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Long-distance migrations of hover flies (Diptera: Syrphidae)
Hlaváček, Antonín ; Hadrava, Jiří (advisor) ; Černý, Martin (referee)
Long-distance migration of insects is well-known phenomenon, studied especially in butterflies and locusts. Until now, the migration of hover flies (Diptera: Syrphidae) was considered a rather marginal issue and not much attention has been given to it. However, billions of hoverflies take part in the spring and autumn migration every year, transferring hundreds of tonnes of biomass and nutrients. The aim of this thesis is to review an existing knowledge on the migration of hoverflies in context of their ecology and evolution. In the first part, I discuss the biogeography and diversity of migratory hover flies, methods for studying migration and the application of such methods in hover flies migration. In the following chapters, I focus on the migration of particular species in context of their ecology and evolution, especially on population dynamics, phenology, orientation, and dimorphism in the migratory generation.
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Graphlets in Complex Networks
Trlifaj, Daniel ; Hartman, David (advisor) ; Černý, Martin (referee)
Analyzing the characteristics of complex networks is a principal task of network sci- ence. In this thesis, we study graphets, small induces subgraphs rooted in a vertex, as a tool to describe and compare networks. First, we use graph theory to explore the theo- retical properties of graphlets, propose a framework for studying them, and make novel observations. We discuss the link between graphlets and the Weisfeiler-Lehman isomor- phism test and the reconstruction conjecture. We prove that the knowledge of graphlets of size n − 1 for certain graphs is sufficient for their reconstruction. Second, we develop several graphlet-based metrics and apply them to real-world networks and their models. In line with prior literature, the results suggest that graphlets are potentially an excellent tool of characterizing networks. Counter to prior literature, the results suggest that the Albert-Barabási model produces more realistic synthetic networks than other models. 1
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