Juan Carlos Sáenz-Díez Muro

Characterisation of friction stir spot welding process based on envelope analysis of vibro-acoustical signals

Abstract The evaluation of the relationship between the vibro-acoustical signals generated by friction stir spot welding (FSSW) process with its parameters and stages such as torque, dwell time, and tool rotation speed, is developed in this work. A dissimilar lap-joint was conducted using pure copper and AA1050 H24 aluminium alloy. The vibro-acoustical signals in Z and Y directions, and torque applied by the tool during the process have been acquired by the instrument NI USB-9234. The characterisation in the time and frequency domains of the vibro-acoustical signals has been performed in order to correlate them with the stages of processing and tool torque. The analysis has confirmed that the vibro-acoustical signals were significantly affected by changes in process forces and can thus be used as a non-destructive method for process monitoring, optimisation tasks, and control of FSSW process.

Impact of human factor on flexibility and supply chain agility of La Rioja wineries

Human factors play an important role in the success of companies, especially in the performance of production systems. In this research paper, we propose a structural equation model that measures the impact of four human factors (knowledge, abilities, skills, and availability) on production process flexibility and supply chain agility in the wine industry of La Rioja, Spain. The results obtained indicate that these human factors have a direct and positive impact on production process flexibility and supply chain agility. Likewise, they can be indirectly linked to supply chain agility through production process flexibility. Based on these findings, this research encourages La Rioja wineries to jointly work with viticulture and enology programs of Spanish universities. This collaboration would enhance the impact of human factors on the wine industry, which would in turn allow wineries to rapidly and more effectively respond to customer needs. [Received 6 November 2015; Revised 15 October 2016; Revised 7 March 2017; Accepted 10 July 2017]