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The purpose of a rigid pavement design is to determine the thickness of the layers and the quality of the materials used in the pavement. The stresses occurring in a pavement should not exceed the modulus of rupture of the concrete. In this study, the answer to the most reliable and cost-effective solution for a pavement design for a single axle and different temperature gradients was investigated. 3D finite element analysis (FEA) using the ABAQUS package program was carried out with the Taguchi method. A factor, cost to stress difference ratio (Cost/(σ cr − σ max )), was developed to find both the most reliable and the cost-effective solution. The maximum principal stress was calculated by FEA for each of the alternative pavement design. Among the many alternative pavement designs, the solution that gives the minimum cost to stress difference ratio is selected as both the most reliable and cost-effective design.

The choice of intersection type in a road network is one of the most important decisions to be made in transportation engineering. Capacity and level of service are the two main factors considered in the type of intersection design, but safety and economy should also be taken into account when determining the intersection type since these are equally important. A number of parameters can be used to evaluate the performance of an intersection, including travel time, average delay, queue length, fuel consumption and vehicle exhaust emissions. Adding safety and construction costs to these parameters makes decision-making more difficult. In this study, the analytic hierarchy process (AHP) was used as a multi-criteria decision approach to overcome this problem. Three intersection types were modelled and tested using Vissim software in line with the above parameters. An AHP model was then generated using the Vissim results and the AHP results and applicability were analysed.

Rough surfaces of denture prosthesis promote adhesion of microorganisms and plaque formation. In dentistry ferric oxide, tin oxide, chrome oxide and pumice are the most commonly used materials for polishing of resins and other materials. Clinoptilolite that is in zeolitic structure resembles to pumice due to alumina silicate formations in its constitution. Surface roughness was evaluated by means of a surface roughness analyzing instrument, Perthometer There were 10 specimens for each acrylic resin and bis-acryl composite resin material and polishing method combination. Conventional lathe polishing with polishing paste served as surface roughness was determined with a profilometer and SEM microscope. ANOVA was applied to the all measurements and was statistically significant (p<0.001). The p-values were calculated using paired t-tests. The materials in order that are most successful at polishing PMMA surface are; clinoptilolite Ra 0,5 > Fe2O3 Ra 0,6 > Cr2O3 Ra 0,8> pumice Ra 1,2 > SnO2 Ra 1,6. the surface roughness values for Bis-acryl Composite are as follows: clinoptilolite Ra 0,6 > Fe2O3 0,8 Ra > Cr2O3 Ra 0,9 > pumice Ra 1,4 > SnO2 Ra 1,9. The most successful material for PMMA and Composite resin were clinoptilolite followed by; clinoptilolite, Fe2O3, Cr2O3, pumice, and SnO2 in order. The same results were confirmed with the scanning electron microscopic images. Within the light of the present study Clinoptilolite can be an alternative to pumice for polishing of PMMA.

In this study a short follow-up study of plasma sprayed stainless steel femoral implants in dogs was performed. Because of its excellent biologic properties, hydroxyapatite (HA) has been required widely in orthopaedic surgery. In this study HA has been used on metal in a form of a thin coating. The HA material has been derived from calcined (850°C) bovine bone. The bovine HA (BHA) which was produced had nearly the same mechanical properties when compared with the a commercial type HA (CHA) that was investigated in a recent research, that is available in literature There were not any vital complications observed postoperatively after 1.5 month of implantation. The long-term follow-up investigations of this study should be carried out in the future.