|
|
Increasing effectivness of CDN network
Barzali, Mark ; Pluskal, Jan (referee) ; Grégr, Matěj (advisor)
Tato práce představuje koncept sítě pro doručování obsahu Content Delivery Network (CDN) a vymezuje současné problémy, kterým tyto sítě čelí. Následně je představena architektura CDN ve společnosti Seznam.cz. Studie zahrnuje získání výkonnostních metrik CDN Seznam.cz, konkrétně využití sítě a zaplňování mezipaměti, pro přehled o současném stavu CDN. Výsledky obsahují měření z proxy serverů v CDN Seznam.cz, která budou dále porovnávána s budoucími vylepšeními. Celkově výsledky odhalují aktuální stav CDN v existující architektuře a poskytují cenné poznatky pro potenciální optimalizace sítě. Dále jsou diskutovány přístupy, které by mohly pomoct zvýšit efektivitu vyrovnávací paměti ve firmě, detaily implementace a konečné výsledky
|
|
|
Barrier properties of varnishes for protection of photographs
Lokotschová, Radka ; Čeppan, Michal (referee) ; Veselý, Michal (advisor)
In this diploma thesis the basic principles of inkjet print, ink composition, print media and degradation mechanisms of ink dyes are summarized. The thesis deals with study of varnish barrier properties in coloured inkjet prints. Permeability of water vapour and oxygen (parts of atmosphere) depending on different coatings are tested there. In addition the influence of ozone on degradation of dyes was studied, while ozone was permeating through barrier varnish layer of inkjet print. Ozone plays an important role in degradation processes of the inkjet prints and it also causes a gas-fading. Concentrations of acting ozone were established by iodometric titration. Simultaneously kinetics of degradation of Orange 7 was studied on indicator papers.
|
|
|
The Effect of the Time of Bird Droppings Remaining on the Vehicle Body on the Damage Degree of the Paintwork
Bílek, Tomáš ; Kaluža, Zdeněk (referee) ; Bradáč, Albert (advisor)
This diploma thesis deals with the issue of the degree of damage done to the vehicle‘s body paint varnish by bird droppings; with respect to the influence of the pollution time on the thickness of the layer of lacquer. The first chapter deals with the importance of varnish and other layers of body protection, types of body varnish damage, painting technology, lacquer defects, bird droppings and its effects on the varnish of the vehicle‘s body. The second chapter is dedicated exclusively to the description, planning and measurement of the coated layers on the vehicle’s body contaminated with bird feces.
|
|
|
Complete characterization and comparison of lacquer / Ni-P / AZ91 and lacquer / AZ91 systems
Šomanová, Pavlína ; Doskočil, Leoš (referee) ; Buchtík, Martin (advisor)
The aim of this bachelor thesis was to compare the influence of Ni-P coating and varnish on the corrosion properties and chemical – physical properties (adhesion) of the magnesium alloy AZ91. The theoretical part contains the information about the alloy AZ91 itself and its microstructure, following by discussion about Ni-P coating, its properties, the process of the electroless deposition and composition it the nickel bath. Next chapter focuses on information about varnishes, its function and the process of its application on the surface of the substrate. Theoretical part closes with the summary of current research in the field of Ni-P coatings applied on magnesium alloys. The experimental part focuses on analysis of the microstructure of AZ91 alloy. The microstructure of the Ni-P coating and of the system Mg alloy/Ni-P coating/varnish was 4 examined by scanning electron microscope (SEM) and inverted microscope. During the next phase was thickness and hardness measured and composition measured by EDS analysis. The factor of the heat treatment of the samples and its impact on the final microstructure, hardness and corrosion resistance was taken in account. Finally, several samples were modified with the layer of the varnish and its thickness and the influence on the corrosion resistance ware measured. Samples were tested with electromechanical impedance spectroscopy (EIS), the corossion resistance were tested by neutral salt spray (NSS) and adhesive test was performed. The results showed, that Ni-P coating and the layer of varnish had positive impact on the corrosion resistance and the hardness of AZ91. The corrosion resistance of the samples modified with heat treatment was much lower, because of the contracting, which causes creation of the cracks. Also, the layer of varnish had positive effect on anticorrosion properties of tested AZ91 alloy.
|
|
|
Complete characterization and comparison of lacquer / Ni-P / AZ91 and lacquer / AZ91 systems
Šomanová, Pavlína ; Doskočil, Leoš (referee) ; Buchtík, Martin (advisor)
The aim of this bachelor thesis was to compare the influence of Ni-P coating and varnish on the corrosion properties and chemical – physical properties (adhesion) of the magnesium alloy AZ91. The theoretical part contains the information about the alloy AZ91 itself and its microstructure, following by discussion about Ni-P coating, its properties, the process of the electroless deposition and composition it the nickel bath. Next chapter focuses on information about varnishes, its function and the process of its application on the surface of the substrate. Theoretical part closes with the summary of current research in the field of Ni-P coatings applied on magnesium alloys. The experimental part focuses on analysis of the microstructure of AZ91 alloy. The microstructure of the Ni-P coating and of the system Mg alloy/Ni-P coating/varnish was 4 examined by scanning electron microscope (SEM) and inverted microscope. During the next phase was thickness and hardness measured and composition measured by EDS analysis. The factor of the heat treatment of the samples and its impact on the final microstructure, hardness and corrosion resistance was taken in account. Finally, several samples were modified with the layer of the varnish and its thickness and the influence on the corrosion resistance ware measured. Samples were tested with electromechanical impedance spectroscopy (EIS), the corossion resistance were tested by neutral salt spray (NSS) and adhesive test was performed. The results showed, that Ni-P coating and the layer of varnish had positive impact on the corrosion resistance and the hardness of AZ91. The corrosion resistance of the samples modified with heat treatment was much lower, because of the contracting, which causes creation of the cracks. Also, the layer of varnish had positive effect on anticorrosion properties of tested AZ91 alloy.
|
|
|
The Effect of the Time of Bird Droppings Remaining on the Vehicle Body on the Damage Degree of the Paintwork
Bílek, Tomáš ; Kaluža, Zdeněk (referee) ; Bradáč, Albert (advisor)
This diploma thesis deals with the issue of the degree of damage done to the vehicle‘s body paint varnish by bird droppings; with respect to the influence of the pollution time on the thickness of the layer of lacquer. The first chapter deals with the importance of varnish and other layers of body protection, types of body varnish damage, painting technology, lacquer defects, bird droppings and its effects on the varnish of the vehicle‘s body. The second chapter is dedicated exclusively to the description, planning and measurement of the coated layers on the vehicle’s body contaminated with bird feces.
|
|
|
Barrier properties of varnishes for protection of photographs
Lokotschová, Radka ; Čeppan, Michal (referee) ; Veselý, Michal (advisor)
In this diploma thesis the basic principles of inkjet print, ink composition, print media and degradation mechanisms of ink dyes are summarized. The thesis deals with study of varnish barrier properties in coloured inkjet prints. Permeability of water vapour and oxygen (parts of atmosphere) depending on different coatings are tested there. In addition the influence of ozone on degradation of dyes was studied, while ozone was permeating through barrier varnish layer of inkjet print. Ozone plays an important role in degradation processes of the inkjet prints and it also causes a gas-fading. Concentrations of acting ozone were established by iodometric titration. Simultaneously kinetics of degradation of Orange 7 was studied on indicator papers.
|
guest ::
