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Problematics of 3D Concrete Printing
No full textTato disertační práce pojednává o vývoji a využití technologie 3D tisku ve stavebnictví, konkrétně při 3D tisku z betonu. 3D tisk z betonu je v současné době trendem, od kterého si mnozí slibují zefektivnění stavebnictví, snížení nákladů na lidskou sílu, úsporu materiálu, času a možnost vytvářet konstrukce rozličných tvarů. Při této práci spolupracoval autor na vývoji komplexního systému na 3D tisku z betonu, skládajícího se ze samotného strojního zařízení, ovládacího software a vývoji tiskové cementové směsi. Autor byl u vývoje od prvního pokusného smíchání cementu s vodou, až po vytištění jednopodlažního přízemního objektu. Cílem práce je vyvinout vhodnou směs pro 3D tisk, průběžně optimalizovanou na základě získaných zkušeností a zhodnotit potencionální přínos 3D tisku pro společnost. V úvodu práce tak je rozsáhlá rešerše celé technologie, následovaná praktickou částí tvořenou experimentální částí v laboratoři a tisk in situ, závěrem je shrnutí dosažených cílů.This thesis discusses development and use of 3D printing technology in the construction industry, especially 3D printing with a use of concrete. Nowadays, 3D concrete printing is gaining more popularity and many people expect lowering of costs, human labour, construction time and amount of materials. It gives us also an opportunity to produce various shapes of constructions. The author of this thesis cooperated in a development of a complete 3D concrete printing technology, consisting of machine, control software and cement printing mixture. The author participated on the project from the moment of the first experimental mixing to finishing a small one storey structure. The aim of this thesis is to develop a suitable 3D printing mixture, find a way to optimise this mixture and evaluate the potential benefit of this technology for society. First part of this text is a state of the art in 3D printing, followed by physical experiments in laboratory and on construction site, the final part is a summary of achieved objectives
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Development of polyurethane screed for reparation of concrete floors
No full textkatedra materiálového inženýrství a chemi
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Properties and reuse of ashes from municipal solid waste incineration in civil engineering
No full textkatedra materiálového inženýrství a chemi
Damage of porous rocks by crystalizing salts
Get PDFPředmětem diplomové práce je stanovení trvanlivosti a s tím souvisejících vlastností vybraných typů sedimentárních porézních hornin a nalezení rozhodujících parametrů ovlivňujících jejich výdrž. Trvanlivost zkoumaných vzorků českých pískovců bude laboratorně testována odolností vůči změnám teplot a relativních vlhkostí a především vůči rozdílným krystalizacím solí použitých v experimentech. Výsledky těchto měření pomohou vysvětlit a zobecnit mechanické vlastnosti zkoumaných druhů pískovců a pomohou popsat faktory ovlivňující trvanlivost těchto vzorků.The main aim of this thesis is to determine the durability and related properties of selected types of porous sedimentary rocks and finding critical parameters affecting their durability. The durability of the samples examined - Czech sandstones - will be laboratory tested by resistance to changes in temperature and relative humidity, and especially towards varying crystallization of salts used in the experiments. The results of these measurements will help explain and generalize the mechanical properties of studied sandstones and help describe the factors affecting durability of these samples
Basic, mechanical and thermal properties of concrete from MSWI slag
No full textkatedra materiálového inženýrství a chemi
Design of industrial concrete mixture with fine brick dust
No full textkatedra materiálového inženýrství a chemi
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