Open Access. Powered by Scholars. Published by Universities.®

Applied Mechanics Commons™

Open Access. Powered by Scholars. Published by Universities.®

2005

Articles 1 - 6 of 6

Full-Text Articles in Applied Mechanics

Top-Down Structure And Device Fabrication Using In Situ Nanomachining, Xiaodong Li, Xinnan Wang, Qihua Xiong, Peter C. Eklund Dec 2005

Top-Down Structure And Device Fabrication Using In Situ Nanomachining, Xiaodong Li, Xinnan Wang, Qihua Xiong, Peter C. Eklund

Faculty Publications

We demonstrate the potential of an alternative tool for the fabrication of nanoscale structures and devices. A nanoindenter integrated with an atomic force microscope is shown to be a powerful machine tool for cutting precise length nanowires or nanobelts and for manipulating the shortened wires. We also demonstrate its utility in cutting grooves and fabricating dents (or periodic arrays of dents) in ZnSnanobelts. This approach permits the direct mechanical machining of nanodevices that are supported on a substrate without the inherent complications of e beam or photolithography.

Go to article

Load And Resistance Factor Calibration For Wood Bridges, Andrzej S. Nowak, Christopher D. Eamon Nov 2005

Load And Resistance Factor Calibration For Wood Bridges, Andrzej S. Nowak, Christopher D. Eamon

Civil and Environmental Engineering Faculty Research Publications

The paper presents the calibration procedure and background data for the development of design code provisions for wood bridges. The structural types considered include sawn lumber stringers, glued-laminated girders, and various wood deck types. Load and resistance parameters are treated as random variables, and therefore, the structural performance is measured in terms of the reliability index. The statistical parameters of dead load and live (traffic) load, are based on the results of previous studies. Material resistance is taken from the available test data, which includes consideration of the post-elastic response. The resistance of components and structural systems is based on …

Go to article

Evaluation Of Accuracy And Efficiency Of Some Simulation And Sampling Methods In Structural Reliability Analysis, Christopher D. Eamon, Michel D. Thompson, Zhenyu Liu Jul 2005

Evaluation Of Accuracy And Efficiency Of Some Simulation And Sampling Methods In Structural Reliability Analysis, Christopher D. Eamon, Michel D. Thompson, Zhenyu Liu

Civil and Environmental Engineering Faculty Research Publications

Numerous simulation and sampling methods can be used to estimate reliability index or failure probability. Some point sampling methods require only a fraction of the computational effort of direct simulation methods. For many of these methods, however, it is not clear what trade-offs in terms of accuracy, precision, and computational effort can be expected, nor for which types of functions they are most suited. This study uses nine procedures to estimate failure probability and reliability index of approximately 200 limit state functions with characteristics common in structural reliability problems. The effects of function linearity, type of random variable distribution, variance, …

Go to article

Mechanics Of Hydrogenated Amorphous Carbon Deposits From Electron-Beam-Induced Deposition Of Paraffin Precursor, W. Ding, D. A. Dikin, X. Chen, R. D. Piner, R. S. Ruoff, E. Zussman, X. Wang, Xiaodong Li Jul 2005

Mechanics Of Hydrogenated Amorphous Carbon Deposits From Electron-Beam-Induced Deposition Of Paraffin Precursor, W. Ding, D. A. Dikin, X. Chen, R. D. Piner, R. S. Ruoff, E. Zussman, X. Wang, Xiaodong Li

Faculty Publications

Many experiments on the mechanics of nanostructures require the creation of rigid clamps at specific locations. In this work, electron-beam-induced deposition(EBID) has been used to depositcarbonfilms that are similar to those that have recently been used for clamping nanostructures. The film deposition rate was accelerated by placing a paraffin source of hydrocarbon near the area where the EBIDdeposits were made. High-resolution transmission electron microscopy, electron-energy-loss spectroscopy, Raman spectroscopy, secondary-ion-mass spectrometry, and nanoindentation were used to characterize the chemical composition and the mechanics of the carbonaceous deposits. The typical EBIDdeposit was found to be hydrogenated amorphous carbon (a-C:H) having …

Go to article

Effect Of Edge-Stiffening And Diaphragms On The Reliability Of Bridge Girders, Christopher D. Eamon, Andrzej S. Nowak Mar 2005

Effect Of Edge-Stiffening And Diaphragms On The Reliability Of Bridge Girders, Christopher D. Eamon, Andrzej S. Nowak

Civil and Environmental Engineering Faculty Research Publications

Secondary elements such as barriers, sidewalks, and diaphragms may affect the distribution of live load to bridge girders. The objective of this study is to evaluate their effect on girder reliability if these elements are designed to be sufficiently attached to the bridge so as not to detach under traffic live loads. Simple span, two lane structures are considered, with composite steel girders supporting a reinforced concrete deck. Several representative structures are selected, with various configurations of barriers, sidewalks and diaphragms. Bridge analysis is performed using a finite element procedure. Load and resistance parameters are treated as random variables. Random …

Go to article

Medical Technology: Contexts And Content In Science And Technology, Michael A. De Miranda, Mark Doggett, Jane T. Evans Jan 2005

Medical Technology: Contexts And Content In Science And Technology, Michael A. De Miranda, Mark Doggett, Jane T. Evans

Architectural and Manufacturing Sciences Faculty Publications

No abstract provided.

Go to article