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The analysis and simulation of water quality in distribution networks is a complex issue of great concern today. The analysis of the evolution of water age as a simple indicator of water quality in the network is of great interest in both the design and operation phases. Understanding the factors that have the strongest influence on water quality is key to developing adequate strategies aimed at preserving it. This paper first analyses the factors with the biggest influence on the tank's water age to support the selection of the most appropriate configuration from the point of view of water quality during design phases. Then, the main considerations when modelling tanks following the different mixing models considered in Epanet are presented. Also, real tank behaviour is characterised through field measurements and Epanet simulations in order to determine the best-fitting mixing model. [ABSTRACT FROM AUTHOR]

In this paper, several methods for the calculation of water quality evolution in drinking water distribution networks are analysed. The Lagrangian Time-Driven method has been implemented in the Epanet simulation software since version 2.0. In version 2.2, some improvements were implemented to deal with mass imbalances (Lagrangian Time-Driven improved method). However, it sometimes presents inaccuracies in calculations, especially when there are short-length pipes. To solve this problem, the implementation of the Lagrangian Event-Driven method is proposed, which provides more accurate quality results. In order to detail the differences and similarities of the results of the different methods and to determine under what conditions the results provided by Epanet are sufficiently adjusted, two practical examples have been carried out, one of them on a hydraulic model of a real network. [ABSTRACT FROM AUTHOR]

The constant growth of the population and the increase in the need for resources create challenges, and it is necessary to seek more sustainable solutions to manage them more adequately and efficiently. In recent years, the use of renewable energy systems has increased, in which water distribution networks are no exception. Pumps operating as turbines (PATs) are an innovative solution with enormous potential to achieve these sustainable development goals. As a means of improving sustainability, in this research, an optimized regulation tool is developed to maximize the recovered energy in the system using PATs in water distribution networks (WDNs). This is possible due to the use of empirical methods for the estimation of the characteristic curves. The tool was developed in Simulink MATLAB, in which the optimization and iterative steps were carried out. It is based on the intended methodology and applied to a real case study. When implementing the tool, the results given are the hydraulic–electrical regulation strategies, where the number of machines working, the frequency inverter setpoint, and the degree of opening of the pressure-reducing valves (PRV) is defined for any given time. After the analysis in the case study, the tool recovered 28% of the supplied energy in the system. This daily recovered energy was above 7160 kWh, and it contributed to an increase in efficiency and sustainability. [ABSTRACT FROM AUTHOR]

In our view, there is a general need to gain insights into what a listener does in linguistic interaction and to provide a comprehensive account of listenership from a pragmatic standpoint. This paper examines listener roles and processes in three aspects of communication: verbal understanding, verbal production and negotiation of meaning. Traditional views of communication are invariably speaker-centred and based on coding and decoding processes. This paper contains a critical review of these issues which are then related to foreign/second language teaching. Competent non-native speakers of a language should be able to both produce and interpret language correctly. We believe that social and cognitive pragmatic theories (Linguistic Politeness Theory and Relevance Theory) can be successfully applied to second language production and comprehension. Taking as our starting point Cauldwell’s (1998) caution to the effect that we need knowledge of what happens in real communication before thinking of methodologies to teach foreign languages, this paper reviews the three communicative processes of understanding, production and negotiation, and next addresses the main implications for the establishment of a theory-driven teaching methodology.

The aim of this article is to explore theoretical and methodological aspects of the teaching of pragmatics in a second language. Taking as point of departure the pragmatic continuum, which includes pragmalinguistics and sociopragmatics, we focus on the promotion of sociopragmatic knowledge in classroom contexts. More specifically, it is argued that a revised contextual and interactional view of Brown and Levinson's (1987) model of linguistic politeness, related to such notions as genre and politeness systems, offers suitable tools of pragmatic description for use in teaching and learning second languages. We start with a brief overview of linguistic politeness from a socio-cognitive framework. Then, we revise the main methodological approaches to the teaching of pragmatic knowledge in general and the specific teaching of linguistic politeness in particular. Finally, we make a methodological proposal for use in foreign language instruction. [ABSTRACT FROM AUTHOR]

This paper analyses, from the standpoint of the literary pragmatics, and more specifically from linguistic politeness theory, two Old English texts: the heroic poem The Battle of Maldon and Aelfric's prose narrative of King Edmund's life. The aim is double: first, to show that this type of linguistic analysis is adequate for the study of texts from other historical periods, since the pragmatical focus on the text opens up a new interpretive and evaluative dimension. Second, to validate the applicability of politeness theory as an analytical framework in texts and contexts where it has not been commonly applied. [ABSTRACT FROM AUTHOR]