Numerical assessment of the influence of cutting operations on the fatigue strength of metals

Presentation delivered by Luis Antonio Gonçalves from CIMNE during the 17th International Conference on Computational Plasticity, Fundamentals and Applications (COMPLAS) taking place from 5 – 7 of September in Barcelona, Spain.The Fatigue4Light project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 10100684

The discrete energy method in numerical relativity: Towards long-term stability

The energy method can be used to identify well-posed initial boundary value problems for quasi-linear, symmetric hyperbolic partial differential equations with maximally dissipative boundary conditions. A similar analysis of the discrete system can be used to construct stable finite difference equations for these problems at the linear level. In this paper we apply these techniques to some test problems commonly used in numerical relativity and observe that while we obtain convergent schemes, fast growing modes, or ``artificial instabilities,'' contaminate the solution. We find that these growing modes can partially arise from the lack of a Leibnitz rule for discrete derivatives and discuss ways to limit this spurious growth.Comment: 18 pages, 22 figure

The multiple ontologies of freshness in the UK and Portuguese agri-food sectors

This paper adopts a material-semiotic approach to explore the multiple ontologies of ‘freshness’ as a quality of food. The analysis is based on fieldwork in the UK and Portugal, with particular emphasis on fish, poultry, and fruit and vegetables. Using evidence from archival research, ethnographic observation and interviews with food businesses (including major retailers and their suppliers) plus qualitative household-level research with consumers, the paper unsettles the conventional view of freshness as a single, stable quality of food. Rather than approaching the multiplicity of freshness as a series of social constructions (different perspectives on essentially the same thing), we identify its multiple ontologies. The analysis explores their enactment as uniform and consistent, local and seasonal, natural and authentic, and sentient and lively. The paper traces the effects of these enactments across the food system, drawing out the significance of our approach for current and future geographical studies of food

The Effects of Customer Satisfaction, Relationship Commitment Dimensions, and Triggers on Customer Retention

In a study of telecommunications services, the authors examine the effects of customer satisfaction, affective commitment, and calculative commitment on retention. The study further examines the potential for situational and reactional trigger conditions to moderate the satisfaction–retention relationship. The results support consistent effects of customer satisfaction, calculative commitment, and prior churn on retention. Prior churn also moderates the satisfaction–retention relationship. The results have implications for both customer relationship managers and researchers who use satisfaction surveys to predict behavior.Johnson5_The_effects_of_customer_satisfaction_relationship_commitment.pdf: 48400 downloads, before Aug. 1, 2020

Letter to the editor. Novel finite-differencing techniques for numerical relativity: application to black hole excision

We use rigorous techniques from numerical analysis of hyperbolic equations in bounded domains to construct stable finite-difference schemes for Numerical Relativity, in particular for their use in black hole excision. As an application, we present 3D simulations of a scalar field propagating in a Schwarzschild black hole background

Experience with the ALPI linac resonators

Abstract The medium β section of the linac accelerator ALPI [G. Fortuna et al., Nucl. Instr. and Meth. A 328 (1993) 236] is now in operation: beams of 32 S, 37 Cl, 58 Ni, 76 Ge, 81 Br were accelerated for nuclear physics experiments in the first half of 1995. The medium β section of ALPI includes 12 cryostats containing four accelerating quarter-wave resonators each ( β = 0.11, f = 160 MHz). Two similar resonators are installed in a buncher cryostat and two in a rebuncher unit. Accelerating fields around 2.5 MV/m are available. The experience in cavity preparation, installation, conditioning and operation is described