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Industry 4.0 advocates an intensive use of information and communication technologies in manufacturing facilities for achieving sustainability and success in a market with exigent and informed consumers willing personalized products and services. Three main concepts of the Industry 4.0 paradigm are addressed: cyber-physical systems, the Internet of Things, and virtualization. A Petri net model of a smart factory regarding the Industry 4.0 paradigm is proposed as virtualization for decision making support. Enhanced computing and communication capabilities of machines and products allow implementing the approach of mass customization. Any product is associated to a sequence of services, being able to request them to the appropriate machines. The formalism of the object Petri nets has been chosen, where a token net is associated to the product and a system net to the facility. The resulting model can be considered for analysis, performance evaluation, and decision making support.

The bioethanol industry is one of the growing sectors worldwide which is seeking for sustainability along its supply chain. The increasing demand for bioethanol makes this industry face a conflict: to increase productivity without compromising the future natural resources such as water. This work proposes to integrate the water footprint assessment methodology to the supply chain analysis using system dynamics. In this paper, the application of the synergy is to assess and simulate the water footprint of the bioethanol production stages using the system dynamics methodology. System dynamics could be a useful approach to model and simulate the water footprint of bioethanol supply chain and estimate its impact on water resources for the succeeding years.

Different processes to produce a variety of tomato-based products are modeled using the formalism of the Petri nets. From these detailed models a single compact Petri net model is generated, containing all the information of the specific ones. This construction is carried out by means of the transformation methodology from a set of alternative Petri nets into an alternatives aggregation Petri net. As an outcome of this transformation, a simulation model of all the production processes is provided. This model can be used to simulate the behavior of the system in a variety of scenarios. In particular, the proposed model can be the core of a decision support system for the design and operation of a food industry facility.

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]

The use of modelling formalisms for the design of discrete event systems presents many advantages, such as the possibility of structural analysis of the model or performance evaluation. However, the difficulty of the process to obtain an appropriate model of the system requires the use of methodologies to ease the work of the designers. In this paper, two main subjects are discussed. On the one hand, the modular construction of Petri nets alleviates the design process by the use of blocks that can be assembled to build up a complete Petri net model. On the other hand, the development of decision support systems may require the assessment of the performance and properties of complete models obtained from different combinations of modular blocks. The formalism of the alternatives aggregation Petri net may help in the development of compact and efficient models that may reduce the use of scarce computer resources.

Discrete event systems (DESs) provide an approximate approach for dealing with certain types of real systems. DES has been extensively and successfully used in modelling and simulation of technological systems and processes. In this field, coloured Petri nets (CPNs) have arisen as a practical formalism for modelling discrete event systems, widely used thanks to the easiness of their application, as well as the compactness of the resulting models, and the availability of computer software, ready to be used for modelling, simulation, theoretical analysis, as well as performance evaluation. This paper derives from the CPN, a formalism focused on modelling discrete event systems with alternative structural configurations. That is to say, systems with freedom degrees in their structure, which should be solved by decision-makers, deducing the best configuration among a set of alternative structures.

•LCA of the replacement of a conventional boiler by a geothermal boiler.•We study a geothermal vertical installation in a traditional single-family home.•The total amortisation period in terms of environmental impact is 8 years.•The phase with more categories of high environmental impact is the drilling phase.