|
|
The effect of surface modification of acetabular cup on friction coefficient of hip implant
Cahová, Aneta ; Valena, Martin (referee) ; Nečas, David (advisor)
This bachelor’s thesis is focused on limited longevity of hip joint replacements. In order to extend the longevity of replacements effect of microtexture application on surface of artificial acetabulum cup on coefficient of friction was investigated. Attention was paid to composition of model synovial fluid and geometry and layout of texture. For joint simulation, a pendulum hip joint simulator was employed. In first part three femoral heads, two acetabulum cups and five fluids were tested, respectively two heads, four acetabulum cups and one fluid in second part. Significant effect of fluid composition and geometry and layout of texture was observed during measurement. Compared smooth and textured cup the highest decline of friction was 78 %. Results can be used for further research of micortextures. Friction reduction and prolonging lifespan of implants may eventually improve life quality of many patients.
|
|
|
New trends in the field of stone mastic asphalts
Pfeiferová, Magdaléna ; Varaus, Michal (advisor)
The work consists of two parts. The first part is focused on the determination of an anti-skid properties of the test section on Vídenská street. The anti-skid properties will be measured using a pendulum tester and macrotexture will be set at the same time. Microtexture will be measured using a volumetric patch technique. In the second part we will try to gain an initial experience with design and testing of a low noise stone mastic asphalt. We will set basic characteristics and at the same time compare with a standard stone mastic asphalt. For the comparison two various bituminous binders are used. The water sensitivity, resistance against rutting and stiffness moduli are compared.
|
|
|
Pavement skid resistance and Skid Resistance Index
Nekulová, Pavla ; Šachlová, Zora (referee) ; Kudrna, Jan (advisor)
This diploma thesis deals with the relation between the longitudinal friction coefficient dependence on measuring speed and the value of road surface macrotexture MPD. Results of longitudinal friction coefficient and value of MPD measurement on 73 sections are included in this thesis. The results were compared by regression analysis and its outcome was used for determination of formula that enable calculation of longitudinal friction coefficient for any operating speed when longitudinal friction coefficient for 60 km/h and value of macrotexture are known. The evaluation scale for skid resistance index (SRI) was also determined in this thesis. It could be used for evaluation of skid resistance independently of the type of device used for friction coefficient measurement.
|
|
|
Dependance of pavement surface skid resistance on aggregate polishing and traffic loading
Dašková, Jaroslava ; Čelko,, Ján (referee) ; Šachl,, Jindřich (referee) ; Vojtěšek, Antonín (referee) ; Kudrna, Jan (advisor)
Road safety is a complex problem. It is influenced mainly by the driver, the vehicle and the road surface. This thesis is focused on the road surface properties and especially skid resistance that directly affect the braking distance and keeping the vehicle in the horizontal curves and thus traffic accidents. The thesis deals with the durability of pavement surface skid resistance, the type of pavement layers and aggregate polishing used in wearing course. The aim of this thesis was to develop the methodology for improvement of road surfaces skid resistance durability and implementation of functional test for their assessment.
|
|
|
The effect of surface modification of acetabular cup on friction coefficient of hip implant
Cahová, Aneta ; Valena, Martin (referee) ; Nečas, David (advisor)
This bachelor’s thesis is focused on limited longevity of hip joint replacements. In order to extend the longevity of replacements effect of microtexture application on surface of artificial acetabulum cup on coefficient of friction was investigated. Attention was paid to composition of model synovial fluid and geometry and layout of texture. For joint simulation, a pendulum hip joint simulator was employed. In first part three femoral heads, two acetabulum cups and five fluids were tested, respectively two heads, four acetabulum cups and one fluid in second part. Significant effect of fluid composition and geometry and layout of texture was observed during measurement. Compared smooth and textured cup the highest decline of friction was 78 %. Results can be used for further research of micortextures. Friction reduction and prolonging lifespan of implants may eventually improve life quality of many patients.
|
|
|
Dependance of pavement surface skid resistance on aggregate polishing and traffic loading
Dašková, Jaroslava ; Čelko,, Ján (referee) ; Šachl,, Jindřich (referee) ; Vojtěšek, Antonín (referee) ; Kudrna, Jan (advisor)
Road safety is a complex problem. It is influenced mainly by the driver, the vehicle and the road surface. This thesis is focused on the road surface properties and especially skid resistance that directly affect the braking distance and keeping the vehicle in the horizontal curves and thus traffic accidents. The thesis deals with the durability of pavement surface skid resistance, the type of pavement layers and aggregate polishing used in wearing course. The aim of this thesis was to develop the methodology for improvement of road surfaces skid resistance durability and implementation of functional test for their assessment.
|
|
|
Pavement skid resistance and Skid Resistance Index
Nekulová, Pavla ; Šachlová, Zora (referee) ; Kudrna, Jan (advisor)
This diploma thesis deals with the relation between the longitudinal friction coefficient dependence on measuring speed and the value of road surface macrotexture MPD. Results of longitudinal friction coefficient and value of MPD measurement on 73 sections are included in this thesis. The results were compared by regression analysis and its outcome was used for determination of formula that enable calculation of longitudinal friction coefficient for any operating speed when longitudinal friction coefficient for 60 km/h and value of macrotexture are known. The evaluation scale for skid resistance index (SRI) was also determined in this thesis. It could be used for evaluation of skid resistance independently of the type of device used for friction coefficient measurement.
|
|
|
New trends in the field of stone mastic asphalts
Pfeiferová, Magdaléna ; Varaus, Michal (advisor)
The work consists of two parts. The first part is focused on the determination of an anti-skid properties of the test section on Vídenská street. The anti-skid properties will be measured using a pendulum tester and macrotexture will be set at the same time. Microtexture will be measured using a volumetric patch technique. In the second part we will try to gain an initial experience with design and testing of a low noise stone mastic asphalt. We will set basic characteristics and at the same time compare with a standard stone mastic asphalt. For the comparison two various bituminous binders are used. The water sensitivity, resistance against rutting and stiffness moduli are compared.
|
|
| |
guest ::
