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Series

Mechanical Engineering

1999

Department of Mechanical and Materials Engineering: Faculty Publications

Articles 1 - 4 of 4

Full-Text Articles in Engineering

Breakaway Steel Guardrail Post, Dean L. Sicking, John D. Reid, John R. Rohde Nov 1999

Breakaway Steel Guardrail Post, Dean L. Sicking, John D. Reid, John R. Rohde

Department of Mechanical and Materials Engineering: Faculty Publications

A breakaway guardrail post includes upper and lower post sections spaced apart but connected by a breakaway joint. The joint is attached at one end to the upper post by a first fastener set and connected at a second end by a second fasteners set. Upon impact forces being applied to the upper post section, the first fastener fails and the upper post section rotates downwardly.


Foundation Sleeve For A Guardrail System, Dean L. Sicking, John D. Reid, John R. Rohde Jul 1999

Foundation Sleeve For A Guardrail System, Dean L. Sicking, John D. Reid, John R. Rohde

Department of Mechanical and Materials Engineering: Faculty Publications

A highway guardrail terminal system having horizontally extending guardrail elements mounted on a plurality of posts. Foundation sleeves having an elongated slit along one side retain and support appropriate guardrail posts. A plurality of stiffing ribs extend across the slit at a distal portion of the tube. The sleeves enable a safer and faster removal of broken guardrail posts after vehicular impact.


Adaptive Sampling For Coordinate Metrology, Robert Edgeworth, Robert G. Wilhelm Jul 1999

Adaptive Sampling For Coordinate Metrology, Robert Edgeworth, Robert G. Wilhelm

Department of Mechanical and Materials Engineering: Faculty Publications

An iterative sampling process for dimensional measurement is presented. The strategy is based upon the use of surface normal measurement data to develop an interpolating curve between sample points. The interpolant is used to select subsequent measurement targets iteratively. The process is repeated until the measurement converges to a complete and accurate evaluation of the surface. The required sample size is proportional to part quality. The most accurate parts will require the least sample points; whereas, lower quality parts will require a greater number of total samples. The method is particularly applicable to measurement of complex surfaces with coordinate measuring …


In Situ Stem Technique For Characterization Of Nanoscale Interconnects During Electromigration Testing, Ismail Gobulukoglu, Brian W. Robertson Apr 1999

In Situ Stem Technique For Characterization Of Nanoscale Interconnects During Electromigration Testing, Ismail Gobulukoglu, Brian W. Robertson

Department of Mechanical and Materials Engineering: Faculty Publications

A technique for observing microstructure and morphology changes during annealing or electromigration of 100 nm-scale and smaller interconnects is presented. The technique is based on dynamic in situ characterization using a UHV field-emission scanning transmission electron microscope (STEM) and can enable full microstructural characterization (images, diffraction patterns and compositions) during electromigration testing. Initial steps in the validation of the approach include in situ electron-beam OMCVD of Al-containing wires and observation of these wires. Although the deposition conditions were not optimized. Al-containing wires, with high edge acuity, thickness uniformity, and with minimum interconnect widths as small as 15 nm have successfully …