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Influence of Plastic Deformation on the Residual Stress Distribution and Fatigue Behaviour of High Strength Steels Welds
Mráz, Ľ. ; Karlsson, L. ; Hamak, I. ; Mikula, Pavol ; Vrána, Miroslav
The effects of plastic deformation and cyclic loading on residual stress distribution have been studied at welds in high strength 800 MPa steel. Effects of residual stress levels on fatigue life are also presented. Tensile loading was used to induce precisely controlled plastic deformation at weld toes. Residual stress distributions were measured by neutron diffraction. The influence of fatigue loading on the residual stress level was much smaller than that of plastic deformation. A large drop of residual stresses in the vicinity of the welds was recognised after local straining at the level of 2%. Stresses decreased with up to 550 MPa in the region around the weld toe. The effect of local plastic deformation on fatigue properties was also found to be significant. Fatigue strength more than doubled compared to the non-strained as-welded condition.
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Neutron diffraction analysis of residual strain/stress distribution in the vicinity of high strength welds
Mráz, Ľ. ; Karlsson, L. ; Hamak, I. ; Vrána, Miroslav ; Mikula, Pavol
Residual stresses resulting from non homogeneous heat distribution during welding process belong to most significant factor influencing behavior of welded structures. These stresses are responsible for defect occurrence during welding and they are also responsible for crack initiation and propagation at the either static or dynamic load. The significant effect of weld metal chemical composition as well as the effect of fatigue load and local plastic deformation on residual stress distribution and fatigue life have been recognized for high strength steels welds. The changes in residual stress distribution have then positive effect on cold cracking behavior and also on fatigue properties of the welds [1-3]. Several experimental methods, both destructive and non-destructive, such as hole drilling method, X-ray diffraction, neutron diffraction and others, have been used to examine residual stress distribution in all three significant orientations in the vicinity of the welds. The present contribution summarizes the results of neutron diffraction measurements of residual stress distribution in the vicinity of single-pass high-strength-steel welds having different chemical composition as well as the influence of fatigue load and local plastic deformation. It has been observed that the chemical composition of the weld metal has a significant influence on the stress distribution around the weld. Similarly, by aplying both cyclic load or pre-stress load on the specimens, stress relaxation was observed even in the region of approximately 40 mm far from the weld toe.
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Study of HLA antigens and KIR genes in a donors and recipients of bone marrow
Kroulíková, Zuzana ; Vraná, Milena (advisor) ; Froňková, Eva (referee)
HLA and KIR genes are highly polymorphic regions within the human genome. Protein products of these genes play a critical role in hematopoietic stem cell transplantation. Genetic HLA match is a major barrier to engraftment and influences the outcome of this therapy. Therefore it is necessary to genotype donors and recipients selected for hematopoietic stem cell transplantation. Today HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 genes are tested by modifications of polymerase chain reaction or by sequence-based typing methods on the level of high- or low-resolution. Donors registered in bone marrow registries are selected on the basis of a 10/10 match. Donors KIR genotype leads to a better outcome, to relapse-free survival and overall survival in treatment of patients with acute myeloid leukemia. A better protection against relapse is achieved by Cen-B/B donor haplotype. Therefore KIR typing by polymerase chain reaction is used and the genotype is compared with the IMGT/KIR database by an online B- content calculator. Donors are divided in groups according to their genotype and their influence on the success of treatment for acute myeloid leukemia. The study of polymorphic systems and the development of genotyping donors and recipients significantly improve the outcome of hematopoietic stem cell...
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Concept of smart home energy monitoring and management
Kolouch, Petr ; Wasserbauer, Vojtěch (referee) ; Vrána, Michal (advisor)
This bachelor thesis deals with smart-metering of home. The introduction of the thesis deals with the approach of this issue. It then explains the principle of smart socket operation and the possibility of linking smart sockets with renewable sources. In the next part of the thesis there is a thorough search of existing smart systems in the Czech Republic and abroad. In the practical part, 3 commercial smart sockets were measured and evaluated. The last part is the creation of the concept of smart socket-based on microchip ADE7753. Subsequently, the implementation of the measuring device is detaily described.
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Možnosti výkupu kovových a PET nápojových obalů v České republice
Vrána, Michael
The aim of the diploma thesis titled Repurchase options of metal and PET beverage packages under the conditions of Czech republic, is to make a proposal of deposit-based system for one-way beverage packages. The first part contains current legislation about waste management of packages. On the following pages are describe characteristics of PET bottles and aluminium beverage cans. The third part is about the deposit-based systems in abroad. Authors own part is a survey aimed on willingness of consumer to adapt for a new return system of beverage containers. Most of respondents are willing to adapt for a new deposit-based system. The next part is a proposal of deposit-based system under the condition of Czech republic. Last part is a discussion about the potential impacts of establishing the deposit-based system. My own conclusion is that the deposit-based system is not suitable under the condition of Czech republic.
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Possessive adjectives - interaction between nominal and hard adjectival inflection
Vraná, Michaela ; Synková, Pavlína (advisor) ; Chromý, Jan (referee)
The aim of this work is to complete the view of the Czech gramatics and other studies to the language question of the intraction of possesive adjectives and find out, how the Czech publicists working in chosen commercial media verse in this question of language. In a teoretical part we tried to sum up a picture of possesive adjectives in circumstance Czech linguistics, in a practical part we explained how we approach to the creation of our questionnaire about the use of possessive adjectives of chosen publicists and we described the results of our survey. The main finding was that our respondents tend to answer registry and prefer possessive adjectives before the genitive. This work is beneficial because it summarizes the knowledge referred to in grammars on the subject of possesive adjectives and shows how Czech writers of selected periodicals versed in issues of possessive adjectives.
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Food as cultural and social phenomenon, ethics of dining - gastronomical world
Vrána, Michal ; Šmíd, Jan (advisor) ; Hanuš, Jiří (referee)
TITTLE: Food as cultural and social phenomenon, ethics of dining - gastronomical world. AUTHOR: Michal Vrána DEPARTMENT: Ústav profesního rozvoje pracovníků ve školství SUPERVISOR: PhDr. Jan Šmíd, Ph. D. ABSTRACT: In his thesis on "Food as a cultural and social phenomenon, ethics dining - gastronomic world" by dealing with the phenomenon of food in the context of broader socio-cultural and artistic fields. Introduce general views on food and gastronomy in different historical epochs and civilizations to the present. I will focus primarily on the depiction of "dining" and "stolovací" themes in art history and art production. I will mention the development of rules of etiquette, ritual feasts and social dining. The didactic part, carries out projects in the hour of art education in selected primary school.
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Concept of smart home energy monitoring and management
Kolouch, Petr ; Wasserbauer, Vojtěch (referee) ; Vrána, Michal (advisor)
This bachelor thesis deals with smart metering of home. The introduction of the thesis deals with the approach of this issue. It then explains the principle of smart socket operation and the possibility of linking smart sockets with renewable sources. In the next part of the thesis there is a thorough search of existing smart systems in the Czech Republic and abroad. In the practical part, 3 commercial smart sockets were measured and evaluated. The last part is the creation of the concept of smart socket-based on microchip ADE7753. Subsequently, the implementation of the measuring device is detaily described.
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Prezent and future of human resources management
Vraná, Marcela ; Pivoňková, Lucie (referee) ; Kocianová, Renata (advisor)
The main focus of my thesis is the evolution of personnel work, development of management and corporate culture, current trends and difficulties in the human resources work, the future of human resources management and motivation of employees. The first place is occupied on purpose by the evolution of personnel work, since the thesis is primarily about the human resources management. The development of management gives the chapter a final touch and makes it possible for the reader to find a parallel between different directions in management in the context of a human resources work development. The human resources management as a development stage of the personnel work significantly touches the activities of every organisation; it forms an important part of them. In the environment of many organisations, however, its mission is largely underestimated; the personnel department is perceived as being only an administrative one; often the education and training is chaotic, if any. The attention dedicated to the recruitment of employees and line managers is insufficient. The personnel professionals are to a certain extent disadvantaged within their organisations; their activity is considered auxiliary serving especially for supporting the line management. There occurs a conflict of roles and competencies. In my...
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Proposal for a Business Plan - a Bee Farm
Gross, Jan ; Vrána, Michal (referee) ; Zinecker, Marek (advisor)
The bachelor's thesis concerns with creating of a business plan for establishing a Bee farm which will be situated in Zárubice in Vysočina area and will be carried on a trade. The proposal of business plan is based on theoretical knowledge and on compiled analysis (SWOT) and chooses convenient strategies for for the needs of customers and create a value added creation for the owner.
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