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Mechanical Engineering Commons

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Full-Text Articles in Mechanical Engineering

Design Of A Near-Constant Force Spring For Orthopedic Implants, Christopher Hartman, Paul Rotarius Dec 2010

Design Of A Near-Constant Force Spring For Orthopedic Implants, Christopher Hartman, Paul Rotarius

Honors Theses

The design and testing of a spring assembly for the attachment of an orthopedic implant is presented. The assembly is intended to supply a constant compressive force of approximately 800 lb. at the bone-implant interface, while exhibiting insensitivity to changes in the displacement of the clamping device. This near-constant force will aid in-growth of bone tissue at the implant surface. This constant compressive force was ultimately not attained due to the packaging dimensions and materials available. However, significant improvement was made upon the current design in use by lowering the spring constant around 800 lb.

The final assembly fits in ...


Development Of A Task Assignment Tool To Customize Job Descriptions And Close Person-Job Fit Gaps, Bryan W. Booker Aug 2010

Development Of A Task Assignment Tool To Customize Job Descriptions And Close Person-Job Fit Gaps, Bryan W. Booker

Dissertations

Does the knowledge worker fit the job or should the job fit the knowledge worker? This research developed a methodology and a tool to customize a knowledge worker’s job design to better fit their knowledge, skills, abilities and characteristics. The research outcomes support the customization of the job design to improve person-job fit, the documentation of the customized job design as a position description, and the use of a structured person-task assignment process. The recommended task assignment process includes a job aid that uses multivariate equations to predict expected task performance. Data were collected from two knowledge worker sub-groups ...


Modeling The Momentum And Mass Transfer Within A Micro-Scale Polymer Electrolyte Membrane Fuel Cell For Flows Within The Slip Flow Regime, Sean Tamarun Goudy May 2010

Modeling The Momentum And Mass Transfer Within A Micro-Scale Polymer Electrolyte Membrane Fuel Cell For Flows Within The Slip Flow Regime, Sean Tamarun Goudy

Dissertations

Polymer Electrolyte Membrane (PEM) fuel cell systems are heterogeneous catalytic systems. Although there are many computational models that describe the behavior of PEM fuel cells, few simulate the catalyst surface concentration of reactant gases at the catalyst layer-membrane layer inteface. Most PEM fuel cell models make no distinction between the bulk concentration of reactants and the catalyst surface concentration of reactants. It is the surface concentration that is key when studying PEM fuel cell systems: the reactions occur at the surface of the catalyst.

In addition, few model the dynamics within the non-continuum flow region near the solid surfaces of ...


Optimum Failure Truncated Testing Strategies, Erik Kostandyan May 2010

Optimum Failure Truncated Testing Strategies, Erik Kostandyan

Dissertations

Accumulated fatigue damage on mechanical components due to random stress loads eventually causes failure. Therefore products with lower failure rates are more desirable. Testing mechanical components for their intended purpose under predetermined working conditions is a common practice used by industries to prevent failures. Fatigue tests are categorized as Time Truncated or Failure Truncated, known in the literature as Type I and Type II tests, respectively. In failure truncated tests, the mechanical components are tested until the desired number of results is obtained. The parameters of a typical failure truncated test include the capacity of the test facility, the actual ...