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- Rehabilitation of an industrial water main using multicriteria decision analysisPublication . CarriƧo, Nelson; Covas, DĆdia; Almeida, Maria do CĆ©uThis paper demonstrates the application of multicriteria decision analysis (MCDA) method- ology in a real case study aiming to choose the best rehabilitation intervention of an industrial water main. This methodology is composed of three main stages: problem identification, structuring, and evaluation. Problem structuring, a crucial stage for the outcomes, includes identifying objec- tives, selecting scenarios within the analysis period, defining problem alternatives, and defining the problematic type. Problem evaluation includes the selection of assessment metrics, selection of the aggregation method, application of the method, and a sensitivity and robustness analysis. Two scenarios, nine assessment metrics, and seven alternatives are established, and two ranking methods (the additive model and ELECTRE III method) are used to compare the alternatives. The results show that the best solution corresponds to building a new pipe and deactivating the existing one, as it significantly reduces the pipe failure risk and O&M costs, whereas the worst solution is always the status quo case, since it is the only alternative that does not improve the system performance, independently of the ranking method and the analyzed scenario
- Estudo do impacto das alteraƧƵes climĆ”ticas numa bacia de drenagem urbana: caso de aplicaĆ§Ć£o,Publication . CarriƧo, Nelson; Ferreira, BrunoA presente comunicaĆ§Ć£o tem como objetivo apresentar um estudo de avaliaĆ§Ć£o do impacto das alteraƧƵes climĆ”ticas numa bacia de drenagem localizada na Ćrea Metropolitana de Lisboa. Este sistema inclui uma bacia de bacia de amortecimento de cheias e a jusante desta, uma vala que descarrega no estuĆ”rio do rio Tejo. De referir ainda que o efeito de marĆ© do estuĆ”rio do rio Tejo se faz sentir nesta vala, provocando em alguns casos o assoreamento dos coletores. Junto Ć bacia de amortecimento, num importante entroncamento rodoviĆ”rio,, existem vĆ”rios registos de ocorrĆŖncia de inundaƧƵes. Assim, no presente trabalho para alĆ©m de se diagnosticar a situaĆ§Ć£o atual estudam-se, tambĆ©m, trĆŖs cenĆ”rios futuros de aumento de precipitaĆ§Ć£o
- RepositĆ³rio de ferramentas para a gestĆ£o de sistemas de distribuiĆ§Ć£o de Ć”guaPublication . CarriƧo, Nelson; Ferreira, Bruno; Antunes, AndrĆ©; Caetano, JoĆ£o; Barreira, Raquel; Covas, DĆdiaNo presente artigo apresenta-se um conjunto de ferramentas, disponĆveis em cĆ³digo aberto, para a gestĆ£o de sistemas de distribuiĆ§Ć£o de Ć”gua, desenvolvidas no Ć¢mbito dois projetos de investigaĆ§Ć£o, financiados pela FundaĆ§Ć£o para a CiĆŖncia e Tecnologia (FCT), o projeto DECIdE (https://decide.ips.pt/) e o projeto WISDom (https://wisdom.ips.pt/). No Ć¢mbito do projeto DECIdE, foram desenvolvidas ferramentas que permitem importar e tratar dados, atravĆ©s de ficheiros exportados de sistemas de informaĆ§Ć£o geogrĆ”fica (SIG), em formato shapefile, folhas de cĆ”lculo com mediƧƵes para o cĆ”lculo de balanƧos hĆdrico e energĆ©tico e, tambĆ©m, de indicadores de desempenho de sistema, como por exemplo, perdas por quilĆ³metro de conduta. No projeto WISDom, foram desenvolvidas ferramentas para a localizaĆ§Ć£o Ć³tima de sensores de pressĆ£o, para o processamento de dados de caudal, para identificaĆ§Ć£o de zonas crĆticas da rede de distribuiĆ§Ć£o e para priorizaĆ§Ć£o de condutas para intervenƧƵes de reabilitaĆ§Ć£o. Estas ferramentas sĆ£o Ćŗteis para apoiar os tĆ©cnicos das entidades gestoras na operaĆ§Ć£o dos sistemas e sĆ£o um passo na direĆ§Ć£o da transformaĆ§Ć£o digital.
- Optimal number of pressure sensors for real-time monitoring of distribution networks by using the hypervolume indicatorPublication . Ferreira, Bruno; CarriƧo, Nelson; Covas, DĆdiaThis article proposes a novel methodology to determine the optimal number of pressure sensors for the real-time monitoring of water distribution networks based on a quality hypervolume indicator. The proposed methodology solves the optimization problem for different numbers of pressure sensors, assesses the gain of installing each set of sensors by means of the hypervolume indicator and determines the optimal number of sensors by the variation of the hypervolume indicator. The methodology was applied to a real case study. Several robustness analyses were carried out. The results demonstrate that the methodology is hardly influenced by the method parameters and that a reasonable estimation of the optimal number of sensors can be easily achieved.
- Multi-criteria decision analysis in urban water asset managementPublication . CarriƧo, Nelson; Covas, DĆdia; Almeida, Maria do CĆ©uThis paper presents a multi-criteria decision support methodology for selection and prioritization of rehabilitation intervention in urban water infrastructures considering performance, cost and risk and a long-term perspective. This methodology is divided into three main stages: problem identification, structuring and evaluation. Problem structuring, a crucial stage for the outcomes, includes identifying objectives, selecting scenarios within the analysis period, defining problem options and the problematic type. Problem evaluation includes the selection of assessment metrics, selection of the aggregation method, application of the method and sensitivity and robustness analysis and final recommendations. The methodology is applied to a real case study of a water distribution system, being the different stages presented in detail and obtained results discussed.
- MĆ©todo multicritĆ©rio aplicado ao planeamento de reabilitaĆ§Ć£o em redes de distribuiĆ§Ć£o de Ć”guaPublication . Caetano, JoĆ£o; CarriƧo, Nelson; Covas, DĆdiaO presente artigo tem como objetivo a aplicaĆ§Ć£o de um mĆ©todo multicritĆ©rio de apoio Ć decisĆ£o a um caso de estudo para a definiĆ§Ć£o de condutas candidatas a intervenĆ§Ć£o de reabilitaĆ§Ć£o. Para tal, escolheu-se o ELECTRE TRI-B, da famĆlia dos mĆ©todos ELimination Et Choix Traduisant la REalitĆ© (ELECTRE), dado que permite uma razoĆ”vel flexibilidade na priorizaĆ§Ć£o de investimentos em reabilitaĆ§Ć£o, comportando desvios, face Ć s disponibilidades financeiras e planos orƧamentais, e atendendo a distintos critĆ©rios e mĆ©tricas de avaliaĆ§Ć£o. O caso de estudo permitiu identificar as dificuldades encontradas na aplicaĆ§Ć£o deste mĆ©todo, sendo realizadas consideraƧƵes relativas ao estabelecimento dos parĆ¢metros estruturais do mĆ©todo e Ć anĆ”lise das preferĆŖncias dos decisores, sendo estes aspetos crĆticos e condicionantes para os resultados finais. Outra constataĆ§Ć£o importante Ć© o impacto da escassez ou inexistĆŖncia de informaĆ§Ć£o organizada e disponĆvel, que impossibilita o estabelecimento de mĆ©tricas abrangentes. O desenvolvimento de uma metodologia generalista de apoio Ć decisĆ£o com base no mĆ©todo ELECTRE TRI-B Ć© um processo complexo.
- Computational Tools for Supporting the Operation and Management of Water Distribution Systems towards Digital TransformationPublication . CarriƧo, Nelson; Ferreira, Bruno; Antunes, AndrĆ©; Caetano, JoĆ£o; Covas, DĆdiaThis paper presents a set of computational tools specially developed for supporting the operation and management of water distribution systems towards digital transformation of water services. These tools were developed in the scope of two R&D projects carried out in Portugal, DECIdE and WISDom, during 2018ā2022. The DECIdE project focused on the development of tools for importing cadastral and operational data, as well as on the three operational tools for supporting the performance assessment: the first allows the calculation of different key performance indicators, both at a global and sectorial level, which is an annual requirement of the water regulator, and the other two allow the calculation of the water and the energy balances and a set of complementary indices. The WISDom project aimed at the implementation of applications that directly address specific water utility needs, namely, the flow rate data processing, the optimal location of pressure sensors, the identification of critical areas in the distribution network for pipe burst location, and the prioritization of pipes for rehabilitation. Implemented tools are useful to support water utilities in the daily operation and management of their systems, being a step forward towards digital transformation of the water sector.
- DeteĆ§Ć£o em tempo real de roturas recorrendo a dados de monitorizaĆ§Ć£o da rede de distribuiĆ§Ć£o de Ć”guaPublication . Ferreira, Bruno; CarriƧo, Nelson; Covas, DĆdiaA presente comunicaĆ§Ć£o apresenta a aplicaĆ§Ć£o de uma abordagem estatĆstica para a deteĆ§Ć£o de roturas em redes de distribuiĆ§Ć£o de Ć”gua. A abordagem estatĆstica avalia continuamente os dados de caudal, recebidos a partir de um caudalĆmetro instalado Ć entrada da rede, e de forma a identificar perĆodos de mediƧƵes anĆ³malas. Os eventos de rotura sĆ£o detetados quando os perĆodos de mediƧƵes anĆ³malas excedem uma determinada duraĆ§Ć£o prĆ©- definida. A abordagem estatĆstica Ć© aplicada a dados de caudal de dois casos de estudo. Devido Ć inexistĆŖncia de dados reais sobre roturas, o estudo incidirĆ” sobre a introduĆ§Ć£o artificial de roturas nos dados de para posterior deteĆ§Ć£o utilizando a abordagem estatĆstica. O objetivo Ć© determinar os parĆ¢metros da abordagem estatĆstica que permitem minimizar (para cada caso de estudo) o tempo necessĆ”rio para deteĆ§Ć£o e o nĆŗmero de falsos positivos. Os resultados obtidos permitem concluir que: i) a abordagem estatĆstica pode ser parametrizada para minimizar o tempo necessĆ”rio para deteĆ§Ć£o, ou, alternativamente, o nĆŗmero de alarmes falsos positivos; ii) os melhores parĆ¢metros dependem da dimensĆ£o da rotura a ser detetada; e iii) para o mesmo caso de estudo, os melhores parĆ¢metros para uma rotura de uma determinada magnitude variam ao longo do ano.
- Flowrate time series processing in engineering tools for water distribution networksPublication . Ferreira, Bruno; CarriƧo, Nelson; Barreira, Raquel; Dias, Tiago; Covas, DĆdiaThe current paper presents a comprehensive methodology for processing unevenly (and evenly) spaced flowrate time series for subsequent use in engineering tools, such as the calibration of hydraulic models or the detection and location of leaks and bursts. The methodology is a four-step procedure: (a) anomaly identification and removal, (b) short-duration gap reconstruction, (c) time step normalization, and (d) long- duration gap reconstruction. The time step normalization is carried out by a numerical procedure prior to the reconstruction process. This reconstruction process uses a pattern model coupled with regression techniques (i.e., autoregressive integrated moving average and exponential smoothing). The methodology is calibrated using Monte Carlo simulations applied to a water utility flowrate time series and validated with two additional time series from different water utilities. Obtained results demonstrate that the proposed methodology can process flowrate time series from water supply systems with different characteristics (e.g., consumption pattern, data acquisition system, transmission settings) both for normal operating conditions and during the occurrence of abnormal events (e.g., pipe bursts). This methodology is a very useful tool for the daily management of water utilities, preparing the time series to be used in different engineering tools, namely, hydraulic simulation, model calibration or online burst detectio
- The challenge of the digitalization of the water sectorPublication . CarriƧo, Nelson; Ferreira, Bruno; Antunes, AndrĆ©; Caetano, JoĆ£oThe digitalization of the water sector is of utmost importance for improving the efficiency and sustainability of the managed systems. The digitalization process, however, can be seen as a ladder with several steps that the water utility must climb to become a smart utility. The reality is that many water utilities worldwide have not realized yet the benefits of digital transformation and, thus, the digitalization of the water sector lags behind other industries. This chapter presents the major challenges and the promising future that water utilities face in the journey of digitalization. Guidelines on how to choose the most adequate digital solution are also presented, as well as the trends for a smarter water utility.