Water saturation induced changer in the indirect (Brazilian) tensile strength and the failure mode of some igneous rock materials

The present study concentrates on water induced strength reduction and variation of the failure mode in indirect (Brazilian) tension tests of several igneous rock materials under three moisture cases of oven-dry, air-dry and fully saturated states. In this respect, two andesite and three tuff materials which contain no visible flaws were subjected to indirect tensile strength tests using the Brazilian disc method. Once the tension tests were carried out, photographs of the broken samples were taken to investigate the changes in the failure mode. As a result, it was found that tensile strengths of the samples were highly reduced with the presence of the water and the natural humidity. Additionally, it has been deduced that the failure mode of the samples mainly shifts to central fracturing with the presence of natural moisture and saturation. Although the central crack is the ideal type for the theory of Brazilian tensile strength determination, indefinite contact properties like contact angle and frictions are some notable issues to make only considering failure shapes for the validity of the test results misleading

Variation of the Liouville measure of a hyperbolic surface

For a compact riemannian manifold of negative curvature, the geodesic foliation of its unit tangent bundle is independent of the negatively curved metric, up to Holder bicontinuous homeomorphism. However, the riemannian metric defines a natural transverse measure to this foliation, the Liouville transverse measure, which does depend on the metric. For a surface S, we show that the map which to a hyperbolic metric on S associates its Liouville transverse measure is differentiable, in an appropriate sense. Its tangent map is valued in the space of transverse Holder distributions for the geodesic foliation.Comment: AmsLaTeX with package epsfig, 27 pages, 3 figures; one argument corrected in Section 7, minor improvements elsewhere; to appear in Erg. Th. Dyn. Sys

Assessing efficiency of public health and medical care provision in OECD countries after a decade of reform

The objective of this study was to examine the change in efficiency of health care systems of 34 OECD countries between 2000 and 2012, a period marked by significant health reform in most OECD countries. This paper uses a novel Dynamic Network Data Envelopment Analysis (DNDEA) model to analyze the efficiency of the public health system and the medical care system of these OECD countries independently along with assessing the efficiency of their overall health system. This helps understand the relative priorities for improving the overall health system. The data for this study was obtained from the OECD Health Facts database. The study findings suggest that countries which improved their public health system were more likely to show overall improvement in efficiency