Cohomology ring of differential operator rings

We compute the multiplicative structure in the Hocshchild cohomology ring of a differential operators ring and the cap product of Hochschild cohomology on the Hochschild homology.Comment: 20 page

Cartesian Bicategories II

The notion of cartesian bicategory, introduced by Carboni and Walters for locally ordered bicategories, is extended to general bicategories. It is shown that a cartesian bicategory is a symmetric monoidal bicategory

A Reliability Study of Phased Array Ultrasonic Inspections Applied to Aluminothermic Welds in Rails

Nowadays, long welded railway rails are achieved by means of aluminothermic and flush-butt welding processes. Compared to bolted joints, welds proved to be effective in terms of reduced wheel damage, ride comfort and maintenance. However, even if the event is inexplicably not considered in relevant standards, surface cracks often initiate within the welded and the heat affected regions of the foot, leading to brittle failure. On the subject, a recent work developed a probabilistic methodology for determining day-by-day failure probability. However, apart from this structural integrity study and few others, a complete damage tolerance approach should also consider the capability of nondestructive inspections. The latter is recognized as an essential input to define maintenance inspection intervals. The present work is focused on the capability assessment of Phased Array ultrasonic inspection applied to aluminothermic-welded joints by means of Probability of Detection curves, as a result of experimental and Model Assisted data samples

Acoustic emission-based monitoring of fatigue damage in CFRP-CFRP adhesively bonded joints

Adhesively bonded joints are being increasingly applied in modern structures. However, manufacturing defects and particularly harsh operative conditions may cause local debonding and catastrophic failures. Structural health monitoring (SHM) and non-destructive testing (NDT) procedures are then needed to evaluate the in-service structural integrity of adhesively bonded joints. In this research, an adhesively bonded single-lap joint, both adherends of which are manufactured using a carbon fibre-reinforced polymer (CFRP) composite, is subjected to constant amplitude fatigue loading. During such a test, the integrity and damage condition of the joint is continuously monitored using acoustic emission (AE), while the test itself is periodically interrupted in order to apply micro-computed tomography (??CT) to the specimen, with the aim of investigating the real features of the developing fatigue damage. The results show that, after suitable elaboration and filtering by means of pattern recognition algorithms, acoustic emission-based monitoring allows for effective identification and characterisation of the development of fatigue damage in adhesively bonded joints

A cytogenetic investigation on peripheral blood lymphocytes of cattle affected by enzootic bovine leukemia

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