The role of grain bridging in affecting the initial rising portion of the R-curve and the transient, non-steady-state behavior of short cracks during (cyclic) fatigue-crack propagation has been quantitatively examined in a 99.5% pure alumina. Fatigue-crack growth properties for both long and short ( af < 2 mm) cracks emanating from machined notches (root radius, 15–150 m) were investigated, whe...

A typical dynamometer drive shaft was damaged during its working condition. This failure was repeated in four cases. In the present article, a failure analysis of a dynamometer drive shaft has been performed. To analyze the failure, the material investigation was carried out by scanning electron microscopy (SEM) images. Additionally, the micro-structure of the failed coupling shaft was photogra...

Bisphosphonates are commonly prescribed for treatment of osteoporosis. Long-term use of bisphosphonates has been correlated to atypical femoral fractures (AFF). AFFs arise from fatigue damage to bone tissue that cannot be repaired due to pharmacologic treatments. Despite fatigue being the primary damage mechanism of AFFs, the effects of osteoporosis treatments on fatigue properties of cortical ...

This study aimed to determine and analyze the neuromuscular fatigue onset by median frequency (MDF) and the root mean square (RMS) behavior of an electromyographic signal (EMG). Eighteen healthy men with no prior knee problems initially performed three maximum voluntary isometric contractions (MVIC). After two days of MVIC test, participants performed a fatiguing protocol in which they performe...

The very high cycle fatigue behavior (10-10 cycles) of Ti-6246 has been investigated using ultrasonic fatigue techniques. In this regime of fatigue (0.4-0.6σYS), only certain microstructural regions are susceptible to fatigue damage accumulation, and lifetimes are related to the distribution of fatigue critical microstructural neighborhoods. Three distinct categories of crystallographic crack i...

This research aims to explain users’ discontinuous usage behavior in social network context. With system features increasing, information flooding and personal network expanding of SNSs, users begin to emerge social network fatigue, and ultimately express discontinuous usage intention. To explain this phenomenon, we develop a research model based on a cognition-affection-conation framework. Thi...

the welding in cold formed areas is not only an open question for statically loaded sections (brittle fracture) but also for dynamically loaded structures (fatigue resistance). a lot of structures are subjected to dynamic loadings and unfortunately very little information about the influence of welding in the cold formed areas on fatigue resistance is available. in order to establish the fatigu...

statement of problem: the question about resistance of resin composites under rest in removable partial denture (rpd) is still unanswered. it is important to find the strongest material that withstands the applied stresses when used under rpd components. objectives: to evaluate and compare the fatigue behavior of amalgam and composite restorations used under the rest of the removable partial de...

Appendix B-Full Text “Operational Benefits of a Fatigue Risk Management System” Captain Don Gunther, Continental Airlines Abstract Appendix B-Full Text 40 C. PARALLEL SESSION: OPERATIONAL EVIDENCE OF FATIGUE: FLIGHT OPERATIONS 41 “Effects of Fatigue on Operational Performance” John A. Caldwell, Ph.D., Archinoetics, LLC Abstract Appendix B-Full Text 43 “Sleep and Psychomotor Performance during C...

Title of Document: DEVELOPMENT OF FATIGUE MODELS FOR COPPER TRACES ON PRINTED WIRING ASSEMBLIES UNDER QUASI-STATIC CYCLIC MECHANICAL BENDING. Daniel M Farley, Doctor of Philosophy, 2010 Directed By: Professor Abhijit Dasgupta Department of Mechanical Engineering This dissertation investigates the fatigue durability of copper (Cu) traces on printed wiring assemblies (PWAs) under quasi-static cyc...