Effect of simplifications of bone and components inclination on the elastohydrodynamic lubrication modeling of metal-on-metal hip resurfacing prosthesis

It is important to study the lubrication mechanism of metal-on-metal hip resurfacing prosthesis in order to understand its overall tribological performance, thereby minimize the wear particles. Previous elastohydrodynamic lubrication studies of metal-on-metal hip resurfacing prosthesis neglected the effects of the orientations of the cup and head. Simplified pelvic and femoral bone models were also adopted for the previous studies. These simplifications may lead to unrealistic predictions. For the first time, an elastohydrodynamic lubrication model was developed and solved for a full metal-onmetal hip resurfacing arthroplasty. The effects of the orientations of components and the realistic bones on the lubrication performance of metal-on-metal hip resurfacing prosthesis were investigated by comparing the full model with simplified models. It was found that the orientation of the head played a very important role in the prediction of pressure distributions and film profiles of the metal-on-metal hip resurfacing prosthesis. The inclination of the hemispherical cup up to 45 had no appreciable effect on the lubrication performance of the metal-on-metal hip resurfacing prosthesis. Moreover, the combined effect of material properties and structures of bones was negligible. Future studies should focus on higher inclination angles, smaller coverage angle and microseparation related to the occurrences of edge loading. © IMechE 2012

Increasing Shipping in the Arctic and Local Communities’ Engagement : A Case from Longyearbyen on Svalbard

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Employability Skill Development of Mechanical Engineering Students Through Project Based Learning in Vocational High School in South Sulawesi

Abstract: Embedding employability skills in learning requires a learning model that allows effective in improving employability skills of students Learning model that if able to meet these expectations is project based learning. This study aims to determine the contribution of project based learning to employability skills of students of SMK Package Engineering Skills Engineering in South Sulawesi. This research uses quantitative approach with non experimental design with sample size 325 students. Data collection uses questionnaires to obtain data on project-based learning implementation and employability skills. The data of the research were analyzed by using descriptive analysis and regression analysis which previously conducted normality and linearity test. Based on the results of the research is known that the implementation of project based learning model contributes to the development of employability skill students of machining engineering SMK 59.8%