Results 261 to 270 of about 3,073,145 (301)

Stress Ratio and Stress Trajectory Simulations for Devonian Gas Shales

SPE Unconventional Gas Recovery Symposium, 1984
ABSTRACT A brief review of selected in situ stress studies is presented. Pertinent geomechanical factors and rationale for stress trajectory characterizations are discussed in the context of natural fracturing in geological formations. Examples with structural cross sections incorporating the influence of the Rome Trough are identified ...
S.H. Advani, Anthony Andrews, J.K. Lee, C.A. Komar   +3 more
openaire   +1 more source

The effects of stress ratio on fatigue threshold

International Journal of Fatigue, 1990
Abstract Arising from the fact that there is a reverse compression stress around a fatigue crack, it is supposed that there is an equivalent compressive high-strain area. Based upon the eigenequation of crack growth, the critical value, K th c , of the compressive stress intensity factor is derived.
openaire   +1 more source

Effect of stress ratio on the fatigue behaviour of compact bone

Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine, 2005
During the fatigue process of bone, cracks generally initiate from the inherent defects existing in the bone. The fatigue lives of bone specimens at different stress levels as well as at different stress ratios R were evaluated using a computer simulation in which the crack propagation behaviour initiated from the inherent defects in the bone are ...
M, Ota, S, Ishihara, C, Fleck, T, Goshima, D, Eifler   +4 more
openaire   +2 more sources

Reproducibility of pressure transmission ratios in stress incontinent women

Neurourology and Urodynamics, 1993
AbstractPressure transmission ratios (PTR) are obtained during cough pressure profiles (Δ urethral pressure/Δ bladder pressure × 100) and have been extensively used in pre and post operative evaluation of patients with stress urinary incontinence. Sixteen patients with genuine stress were studied to assess the magnitude of PTR variance in incontinent ...
D A, Richardson, A, Ramahi
openaire   +2 more sources

Stress Ratio Effects on Collapse of Compacted Clayey Sand

Journal of Geotechnical Engineering, 1991
A“double‐triaxial” test procedure similar to the double‐oedometer test was developed to determine the wetting‐induced collapse potential of soils subjected to anisotropic stress states. Based on a series of double‐triaxial tests performed on a slightly expansive clayey sand, it was established that the magnitude of volumetric strain resulting from a ...
E.C. Lawton, R.J. Fragaszy, J.H. Hardcastle   +2 more
openaire   +1 more source

Stress ratio contributes to fatigue crack growth in dentin

Journal of Biomedical Materials Research Part A, 2005
AbstractAn experimental study of fatigue crack growth in dentin was conducted, and the influence of stress ratio (R) on the crack growth rate and mechanisms of cyclic extension were examined. Double Cantilever Beam (DCB) fatigue specimens were sectioned from bovine molars and then subjected to high cycle fatigue loading (105 < N < 106) under ...
D, Arola, W, Zheng, N, Sundaram, J A, Rouland   +3 more
openaire   +2 more sources

Evaluation of the Heterophil/Lymphocyte Ratio as a Measure of Stress in Chickens

Avian Diseases, 1983
The number of lymphocytes in chicken blood samples decreased and the number of heterophils increased in response to stressors and to increasing levels of corticosterone in the chicken feed. The ratio of heterophils to lymphocytes was less variable than the number of heterophil or lymphocyte cells, and the range of values for this ratio was greater than
W B, Gross, H S, Siegel
openaire   +2 more sources

The Hypoplastic Model Expressed by Mean Stress and Deviatoric Stress Ratio

2018
Over the past several decades, hypoplasticity has been shwon to be a powerful tool to predict the non-linear behaviour of soils. Early hypoplastic models were developed from trial-and-error procedures and these models are usually expressed in a unique tensorial equation regarding the stress tensor. However, most models for fluid-like soil are expressed
Xuzhen He, Wei Wu, Dichuan Zhang, Jong Kim   +3 more
openaire   +1 more source

Measurement of the effects of stress ratio and changes of stress ratio on fatigue crack growth rate in a quenched and tempered steel

International Journal of Fatigue, 1994
Abstract This paper describes a technique that enables fatigue crack growth rate to be determined for a range of stress ratios, R , using a single specimen. The procedure eliminates some of the scatter normally encountered when data are obtained from multiple specimens.
openaire   +1 more source

Plant hormone regulation of abiotic stress responses

Nature Reviews Molecular Cell Biology, 2022
Rainer Waadt, Po-Kai Hsu, Yohei Takahashi   +2 more
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