Results 251 to 260 of about 185,145 (291)

A Critical Analysis of Transactional Distance Theory

Quarterly Review of Distance Education, 2005
This investigation reviews published empirical studies that attempted to support or to validate transactional distance theory (Moore, 1993). It was found that either data only partially supported the theory or, that if they apparently did so, the studies lacked reliability, construct validity, or both.
Paul Gorsky, Avner Caspi
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Application of the Theory of Critical Distance to Fretting Fatigue

2008
Fretting fatigue occurs at the contact interface of mechanical joints which are designed to be at rest but that nevertheless experience some sort of relative movement due to vibration. This work aims to develop a crack initiation threshold condition for fretting fatigue.
Araùjo A., SUSMEL, Luca, Taylor D., Lopes L. H. M.   +3 more
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Combining phase field method and critical distance theory for predicting fatigue life of notched specimens

International Journal of Mechanical Sciences
Notch features, widely used in engineering components, have negative effect on the fatigue life of structural parts due to the stress concentration caused by their geometry.
Mario Guagliano, Sara Bagherifard, Linglong Zhou   +2 more
exaly   +2 more sources

Extending the theory of critical distances to quasi-brittle fracture

Theoretical and Applied Fracture Mechanics, 2021
Abstract The results of theoretical and experimental studies of brittle and quasi-brittle fracture of plaster plates containing a circular hole and subjected to non-uniformly distributed compression are presented. This paper summarizes the results, partially published by the author earlier.
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Microstructural Parameters in the Theory of Critical Distances

Materials Science Forum, 2007
The work described below investigates, for the first time, the link between microstructural parameters such as grain size and the length constant L which is known as the critical distance. L is frequently used in the prediction of failure processes such as brittle fracture and fatigue, initiated at stress concentration features such as notches.
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The Theory of Critical Distances: A link to micromechanisms

Theoretical and Applied Fracture Mechanics, 2017
Abstract The Theory of Critical Distances (TCD) is a methodology for prediction of the effect of stress concentration features on material failure, especially cracking-related mechanisms such as fatigue and brittle fracture. It has a long history but has become much more relevant to industrial problems in recent years thanks to the widespread ...
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The theory of critical distances: a review of its applications in fatigue

Engineering Fracture Mechanics, 2008
Abstract This paper attempts to review the most interesting findings in the use of the theory of critical distances (TCD) to predict fatigue strength of notched mechanical components. Initially, the most modern formalisations of the TCD are considered, showing their peculiarities and differences.
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The Theory of Critical Distances: Applications in Fatigue

2008
This papers reviews the use of the Theory of Critical Distances (TCD) to predict high-cycle fatigue strength of real components when the complexity of their geometry causes stress concentration phenomena.
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Fatigue analysis of riveted connections using the theory of critical distances

2021
A large number of old metallic bridges have complex riveted details that pose challenges during their fatigue assessment using detail-specific S-N curves. In this paper, the fatigue life prediction capability of a novel method, the Theory of Critical Distances (TCD), which relies on the fatigue properties of the plain material only is investigated ...
Imam, B., Gorouhi, H.
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The Theory of Critical Distances as an alternative experimental strategy for the determination of KIc and ΔKth

Engineering Fracture Mechanics, 2010
Abstract The present technical note is concerned with the use of the Theory of Critical Distances, applied in the form of the Point Method, to estimate the range of the threshold value of the stress intensity factor, Δ K th , as well as the plane strain fracture toughness, K Ic , of conventional engineering materials.
SUSMEL, Luca, TAYLOR, David
openaire   +3 more sources