Implementation of a pipe failure prediction model as a support tool for water networks management strategies

[EN] The work presented in this paper has a dual objective: on the one hand, reaching reliable estimates for the pipes lifespan in a water distribution network; on the other, doing so by means of a relatively low complex model with relatively low need for historical data. The model is based on using the Weibull distribution over two years of failure records. The results achieved are compared with those provided by the well-known Weibull proportional risk model, that have been applied on the same data sets. The comparison is positive in both the location on the Davis curve obtained for each group of pipes, and the relative error existing between both estimates of future failures.[ES] En el presente trabajo se plantea el doble objetivo de, por una parte, alcanzar unas estimaciones fiables para la vida útil de las tuberías que conforman la red de distribución de un abastecimiento y, por otra, hacerlo mediante un modelo de, relativamente, baja complejidad y con poca necesidad de datos históricos. Dicho modelo se ha basado en la utilización de la distribución Weibull sobre registros de dos años de reparaciones. Los resultados alcanzados se han contrastado con los proporcionados por el modelo Weibull de riesgos proporcionales, de amplia difusión en la actualidad, aplicado sobre los mismos conjuntos de datos. La comparativa entre los resultados de ambos modelos ha resultado positiva tanto en la ubicación sobre la curva de bañera obtenida para cada grupo de tuberías, como en el error relativo existente entre ambas estimaciones de fallos futuros.Los autores de este artículo desean agradecer el apoyo prestado, tanto de forma directa como a través de la Cátedra Aguas de Valencia de la UPV, por Global Omnium para el desarrollo de los trabajos aquí presentados.Ramírez, R.; Cobacho, R.; Torres, D.; López-Jiménez, P. (2019). Implementación de un modelo de predicción de fallos orientado a la gestión y estrategias de mantenimiento en redes de distribución de agua potable. Ingeniería del Agua. 23(4):247-258. https://doi.org/10.4995/ia.2019.12151SWORD24725823

Response to control of foliar diseases in environments with different levels of nitrogen

Algunos trabajos sostienen que ante un agregado de nitrógeno (N) puede verse favorecido el desarrollo de las enfermedades por diversas interacciones planta-patógeno, sin embargo existen evidencias que demuestran lo contrario. El objetivo de este trabajo fue evaluar el impacto de dos estrategias de control de enfermedades foliares en cultivos de trigo creciendo en condiciones contrastantes de fertilización nitrogenada (alta y baja disponibilidad, N0 y N1 respectivamente). Para ello se realizaron dos experimentos con objetivos diferentes: (i) evaluar el control de las enfermedades foliares utilizando dos estrategias de control en ambientes de baja y de alta disponibilidad de nitrógeno; y (ii) evaluar el impacto fisiológico de dos grupos diferentes de fungicidas (triazoles y estrobilurinas) en ambientes de baja y de alta disponibilidad de nitrógeno. La principal enfermedad fue “roya de la hoja” (Puccinia tritici Eriksson), la que en la situación de N1 se inició antes respecto a N0. No existieron diferencias en los valores índices de verdor entre cultivos enfermos y sanos (tratamiento convencional). Sin embargo, las sucesivas aplicaciones de fungicida (control total) generaron diferencias en los valores de los índices de verdor en hoja respecto a los otros dos tratamientos. Existieron diferencias significativas en el rendimiento y en el número de granos tanto para la variable disponibilidad de N como para las diferentes estrategias de control de la enfermedad. En N1 se encontraron mayores valores de fotosíntesis. Sin embargo, ninguna diferencia estadísticamente significativa fue encontrada entre ambos principios activos en cuanto a los niveles de fotosíntesis foliar en hoja bandera a lo largo del llenado de los granos.Some studies argue that the addition of nitrogen (N) to a crop can favor the development of diseases due to various plant-pathogen interactions; however, there is evidence to the contrary. The objective of this work was to evaluate the impact of two foliar disease control strategies in wheat growing under contrasting conditions of nitrogen fertilization (high and low availability, N 0 and N respectively). Two experiments were carried out with 1 different objectives: (i) to evaluate the control of foliar diseases using two control strategies in environments with low and high nitrogen availability; (ii) to evaluate the physiological impact of two different groups of fungicides (triazoles and strobilurins) in low and high nitrogen a vailability environments. The main disease was "leaf rust". The disease started earlier in N than in N . 1 0 There were no differences in SPAD values between diseased and healthy cultures (conventional treatment). However, successive applications of fungicide (total control) resulted in differences in leaf SPAD values with respect to the other two treatments. There were significant differences in yield and number of grains for both the variable N availability and the different disease control strategies. Higher levels of photosynthesis were found in N .1 However, leaf photosynthesis levels showed no statistically significant difference between both active principles throughout the grain filling stage.Cátedra de Cerealicultura, Departamento de Producción Vegetal. Universidad de Buenos Aires y CONICE

Implementation of a pipe failure prediction model as a support tool for water networks management strategies

The work presented in this paper has a dual objective: on the one hand, reaching reliable estimates for the pipes lifespan in a water distribution network; on the other, doing so by means of a relatively low complex model with relatively low need for historical data. The model is based on using the Weibull distribution over two years of failure records. The results achieved are compared with those provided by the well-known Weibull proportional risk model, that have been applied on the same data sets. The comparison is positive in both the location on the Davis curve obtained for each group of pipes, and the relative error existing between both estimates of future failures.En el presente trabajo se plantea el doble objetivo de, por una parte, alcanzar unas estimaciones fiables para la vida útil de las tuberías que conforman la red de distribución de un abastecimiento y, por otra, hacerlo mediante un modelo de, relativamente, baja complejidad y con poca necesidad de datos históricos. Dicho modelo se ha basado en la utilización de la distribución Weibull sobre registros de dos años de reparaciones. Los resultados alcanzados se han contrastado con los proporcionados por el modelo Weibull de riesgos proporcionales, de amplia difusión en la actualidad, aplicado sobre los mismos conjuntos de datos. La comparativa entre los resultados de ambos modelos ha resultado positiva tanto en la ubicación sobre la curva de bañera obtenida para cada grupo de tuberías, como en el error relativo existente entre ambas estimaciones de fallos futuros.Peer Reviewe

Management strategies for optimum meter selection and replacement

There are two main decisions faced by utility managers regarding meters in an undertaking: which meter to instal and when to replace it. Traditionally the criteria used to make these decisions have been arbitrary and often imposed by third parties regardless of the situation of the individual undertakings. This paper presents “Comparative billing analysis”, a methodology to analyse meter performance within the undertaking, as a means to support decision making in water meter management. The main difference between the comparative billing analysis and previous methodologies resides in the use of the commercial billing database that most undertakings have these days. By analysing existing data with a systematic approach, it is possible to determine which kind of domestic meter is most appropriate for the utility. This method turns out to be as reliable as previous ones, but much more efficient in the use of economic and human resources.</jats:p

Implementación de un modelo de predicción de fallos orientado a la gestión y estrategias de mantenimiento en redes de distribución de agua potable

&lt;p&gt;En el presente trabajo se plantea el doble objetivo de, por una parte, alcanzar unas estimaciones fiables para la vida útil de las tuberías que conforman la red de distribución de un abastecimiento y, por otra, hacerlo mediante un modelo de, relativamente, baja complejidad y con poca necesidad de datos históricos. Dicho modelo se ha basado en la utilización de la distribución Weibull sobre registros de dos años de reparaciones. Los resultados alcanzados se han contrastado con los proporcionados por el modelo Weibull de riesgos proporcionales, de amplia difusión en la actualidad, aplicado sobre los mismos conjuntos de datos. La comparativa entre los resultados de ambos modelos ha resultado positiva tanto en la ubicación sobre la curva de bañera obtenida para cada grupo de tuberías, como en el error relativo existente entre ambas estimaciones de fallos futuros.&lt;/p&gt;</jats:p

Practical application of metric benchmarking in water supply systems

Metric benchmarking has been widely quoted as a powerful management tool. However, as useful as metric benchmarking can prove, its actual application may present several inconveniences. These include internal resistance to the project, difficulties in finding a suitable partner, finding an appropriate set of indicators, actual data management and results analysis. This paper will present general guidelines to carry out a metric benchmarking project within the water industry, as well as some tools that may be used to overcome some of these difficulties.</jats:p

Towards an Energy Labelling of Pressurized Water Networks

AbstractPressurized Water Systems (PWS) is a key part of a drinking water supply service. Irrigation – the greatest water consumer – is shifting to PWS, making them a vital part of irrigation communities. PWS are energy-hungry. As population grows, water demand (for urban use and for irrigation) rises, and PWS require more energy (4% of total Europe energy, 2% agriculture, 1- 2% drinking water) and, according Euroestat, may reach 100 TWh/year in 2013. In order to reduce greenhouse gas emissions (GHG), to improve PWS energy efficiency is crucial in the way to a lower carbon economy, one of the five key objectives of the Europe 2020 growth strategy.Minimize the energy demand of a network requires to analyze the system as a whole. With this general picture the efforts can be well addressed to the system's parts with higher margin of improvement (think globally, act locally). This paper outlines the procedure to minimize energy consumption of a PWS. Later, following the established protocol, a case study is presented. The analysis shows the huge margin of improvement that in practice can be found. The convenience of labelling PWS energy use is finally underlined

Water End Use Disaggregation Based on Soft Computing Techniques

Disaggregating residential water end use events through the available commercial tools needs a great investment in time to manually process smart metering data. Therefore, it is extremely difficult to achieve a homogenous and sufficiently large corpus of classified single-use events capable of accurately describe residential water consumption. The main goal of the present paper is to develop an automatic tool that facilitates the disaggregation of the individual water consumptions events from the raw flow trace. The proposed disaggregation methodology is conducted through two actions that are iteratively performed: first, the use of an advanced two-step filter, whose calibration is automatically conducted by the Elitist Non-Dominated Sorting Genetic Algorithm NSGA-II; and second, a cropping algorithm based on the filtered water consumption flow traces. As a secondary goal, yet complementary to the main one, a semiautomatic massive classification process has been developed, so that the resulting single-use events can be easily categorized in the different water end uses in a household. This methodology was tested using water consumption data from two different case studies. The characteristics of the households taken as reference and their occupants were unequivocally dissimilar from each other. In addition, the monitoring equipment used to obtain the consumption flow traces had completely different technical specifications. The results obtained from the processing of the two studies show that the automatic disaggregation is both robust and accurate, and produces significant time saving compared to the standard manual analysis