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

Engineering Science and Materials Commons™

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

2006

Discipline
Institution
Keyword
Publication
Publication Type

Articles 121 - 125 of 125

Full-Text Articles in Engineering Science and Materials

Cracking Of Martensitic Alloy Ep-823 Under Controlled Potential, Ajit K. Roy, M. K. Hossain Jan 2006

Cracking Of Martensitic Alloy Ep-823 Under Controlled Potential, Ajit K. Roy, M. K. Hossain

Mechanical Engineering Faculty Research

The susceptibility of martensitic Alloy EP-823 to stress corrosion cracking was evaluated with and without an applied cathodic potential using the slow-strain-rate (SSR) testing technique. The magnitude of the applied potential was based on the corrosion potential determined by cyclic polarization. The cracking susceptibility in an acidic environment at different temperatures was expressed in terms of the true failure stress (ơf), time to failure (TTF), and ductility parameters, including percent elongation (%El) and percent reduction in area (%RA). The data indicate that the magnitudes of ơr, TTF, %El, and %RA were reduced due to cathodic charging. …


Design And Fabrication Of Micro Transducers Using Cured Su-8 Polymer As Main Structural Material, Wen Dai Jan 2006

Design And Fabrication Of Micro Transducers Using Cured Su-8 Polymer As Main Structural Material, Wen Dai

LSU Doctoral Dissertations

Polymer based micro-transducers have many advantages over the traditional silicon based micro-transducers, such as easy integration with metal structures, design flexibility, and low fabrication costs. The characteristics of micro-transducers include converting electrical signals to/from mechanical response, the ability to sustain loading, sensitivity to external excitation, and etc. Some of the difficulties in realizing these characteristics include: characterizing material mechanical properties, techniques for producing electrically conductive polymer structures, and reliable fabrication procedures. In this dissertation, research addressing these difficulties is presented. The developed techniques are demonstrated in the design and fabrication of a SU-8 polymer based comb-drive micro-actuator. The micro-actuator used …


A Micromechanical Approach For Predicting The Complex Shear Modulus And Accumulated Shear Strain Of Asphalt Mixtures From Binder And Mastics, Cristian Druta Jan 2006

A Micromechanical Approach For Predicting The Complex Shear Modulus And Accumulated Shear Strain Of Asphalt Mixtures From Binder And Mastics, Cristian Druta

LSU Doctoral Dissertations

Asphalt mixtures are particulate composite materials consisting of uniformly distributed mineral aggregates, asphalt binder and air voids. Mixtures of asphalt binder and filler, also called mastics, are often assumed to behave as simple viscoelastic materials, where the binders are stiffened by the filler. Because the workability and performance of bituminous mixes are known to be affected by the filler-asphalt mixture (or mastic) properties, this study is intended for performing rheological tests on asphalt binder and mastics and use the results in order to estimate performance parameters of asphalt mixture. The present work uses the PG64-22 asphalt binder test data initially …


Loading And Recovery Behavior Of The Human Lumbar Spine Under Static Flexion, Guntulu Selen Hatipkarasulu Jan 2006

Loading And Recovery Behavior Of The Human Lumbar Spine Under Static Flexion, Guntulu Selen Hatipkarasulu

LSU Doctoral Dissertations

Musculoskeletal disorders account for 32 percent of work related injuries and illnesses. Extensive studies have been conducted to understand and explore the factors that affect the development of musculoskeletal disorders to provide effective control strategies. One of the most important factors that allow effective control strategies is the biomechanical factors. Among the biomechanical risk factors, exposures to repetitive static and vibratory activities are known to result in musculoskeletal disorders. A ligamento–muscular reflex activity exists in humans and animals to stabilize the knee, shoulder, elbow, ankle joints, and spine. This reflex activity decreases over time when static loading is applied, which …


Towards A Generalized Team Task Complexity Model, Ashok Darisipudi Jan 2006

Towards A Generalized Team Task Complexity Model, Ashok Darisipudi

LSU Doctoral Dissertations

The objective of this research was to develop and validate a generalized team task-complexity model and framework by drawing on the literature from various team and task factors grouped into three task-dimensions, which compose task-complexity space and how these affect the task-performance. A number of task typologies have been presented in the teams' literature to better define and understand the critical role of the tasks and the associated team processes. In addition, most of the research work has defined team measures as highly abstract concepts not capable of providing the quantitative comparison of team performances from various domains. This research …