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This work proposes a novel indicator (HCWI) for evaluating water consumption efficiency in hotels. The indicator is built as a relative index that compares the current water consumption with an estimated minimum achievable value. To ensure the representativeness and applicability of the index, the evaluation of this water consumption baseline considers each water consumption micro-component individually and has been simplified, so it only requires fundamental characteristics of the hotel and those that are easy to identify and quantify. A value of the HCWI equal to one indicates the best water use efficiency that can be theoretically achieved with the technology available. On the contrary, larger values of the HWCI indicate high levels of water use inefficiency by the hotel. The applicability of the indicator is tested in six different hotels located in a touristic region in the north of Spain.

[EN] The availability of instantaneous data on water consumption in water utilities of water distribution systems has been increasing due to the increase in the number of customers with smart meters. The analysis of these data allows to improve the billing systems and the customers’ management and to improve the water losses estimate in each water utility. Aiming to evaluate the apparent losses, through the analysis of the water consumption profiles, and real losses, through the study of the minimum night flow, 275 domestic customers of 10 water utilities were measured using a smart meter. The water consumption profiles useful for the global error measurement of the flowmeters park identified the predominant flow between 240 L/h and 1000 L/h, with an insignificant measured volume below 120 L/h (e.g., due to customer leakages). The estimate of the mean water consumption in the minimum consumption period (between 2 h and 5 h a.m.) was 1.2 L/(customer·h) for DN15 flowmeters and 2.0 L/(customer·h) for DN20 flowmeters. Using clustering, four water consumption patterns were also identified, with differences in the consumption scales, trends and peaks during the day. This work demonstrated the potential of smart metering campaigns to collect consumption data. Moreover, it also proposes a methodology and an initial set of statistics about the domestic consumption in each water utility and in the set of water utilities, which is crucial for the technical management of water distribution systems. [PT] O aumento da cobertura de clientes domésticos com telemedição tem levado a uma maior disponibilidade de dados de consumo instantâneo nas Entidades Gestoras (EG) de sistemas de distribuição de água. A análise destes dados, para além de melhorar a gestão dos sistemas de faturação e de gestão de clientes, permite também melhorar a estimativa das perdas de água em cada EG. Com o objetivo de avaliar as perdas aparentes, através da análise de perfis do consumo total, e as perdas reais, por via do estudo do consumo doméstico mínimo, foram realizadas campanhas de telemedição em 275 clientes domésticos referentes a 10 EG. Os perfis de consumo, relevantes para aferição do erro global do parque de contadores, revelaram que os consumos predominantes variam entre 240 e 1000 L/h, sendo o volume medido abaixo de 120 L/h (e.g., devido a fugas domiciliárias) praticamente insignificante. A estimativa do consumo médio de água no período de consumo mínimo (entre as 2 e as 5 h da manhã) foi 1.2 L/(utilizador·h) para contadores DN15 e 2.0 L/(utilizador·h) para contadores DN20. Utilizando análise de clusters, identificaram-se ainda quatro padrões de consumo distintos, diferenciados pelas escalas de consumo, tendências e picos ao longo do dia. Este trabalho demonstrou o potencial das campanhas de telemedição para recolha de dados de consumo. Além disso, forneceu uma metodologia e conjunto inicial de estatísticas sobre o consumo doméstico em cada EG e no conjunto das EG determinante para a gestão técnica dos sistemas de distribuição de água. Os autores agradecem a colaboração das entidades gestoras participantes no projeto Inicativa Nacional para gestão eficiente de perdas (iPerdas 2016). O primeiro autor agradece à Fundação para a Ciência e Tecnologia (FCT), Portugal, pela Bolsa de Doutoramento SFRH/BD/131382/2017. Agradece-se ainda o financiamento da FCT, através do projeto UID/Multi/04621/2019 do CEMAT/IST-ID, Centro de Matemática Computacional e Estocástica, Instituto Superior Técnico, ULisboa.

In recent years, the interaction between light and metallic films have been proven to be a highly powerful tool for optical sensing applications. We have witnessed the development of highly sensitive commercial devices based on Surface Plasmon Resonances. There has been continuous effort to integrate this plasmonic sensing technology using micro and nanofabrication techniques with the optical fiber sensor world, trying to get better, smaller and cost-effective high performance sensing solutions. In this work, we present a review of the latest and more relevant scientific contributions to the optical fiber sensors field using plasmonic materials over the last decade. The combination of optical fiber technology with metallic micro and nanostructures that allow plasmonic interactions have opened a complete new and promising field of study. We review the main advances in the integration of such metallic micro/nanostructures onto the optical fibers, discuss the most promising fabrication techniques and show the new trends in physical, chemical and biological sensing applications.

We present a novel covalent functionalization of a D-shape fiber biosensor based on Lossy Mode Resonances. IgG/anti-IgG model is applied to prove the regeneration of the union and thus the re-usability of the sensor.

Nowadays, optical fiber sensing is an emerging and versatile technology thanks to continuous advances in micro/nanofabrication techniques as well as the application of new nanomaterials. Novel optical fibers combined with a new generation of nanostructured coatings are enabling the development of enhanced optical fiber sensors, for chemical, environmental, and biological applications. Consequently, there is an increasing interest of these fiber-based devices for the monitoring of physical parameters such as temperature, relative humidity, refractive index, strain, and bending, among others, providing higher sensitivity ratios, better detection limits, and improving other sensing parameters. This chapter covers the most used techniques and new trends for the design and nanofabrication of enhanced physical fiber sensors in the last few years. Likewise, an overview of the most relevant applications and an outlook of the optical fiber-based sensing approach for physical parameters is presented.

This work reports a wavelength-based reusable optical fiber sensor for the detection of mercury traces in water based on the alteration of the Localized Surface Plasmon Resonances. The limit of detection is below 1 ppb.

[EN] Accurate water consumption measurement of customers is a crucial component of water utility sustainability. During the last decade, sophisticated measuring technologies without moving components, known as solid-state water meters or static meters, have emerged. Solid-state water meters promise an improved accuracy with more processing and transmission capabilities in comparison with traditional mechanical meters. A compromise needs to be reached between energy consumption and battery life as all these new features are extremely demanding on electric energy. The usual approach adopted by the manufacturer is to reduce the frequency with which static meters take measurements of the circulating flow. This reduction in signal sampling frequency can have a significant effect on the accuracy of the instruments when measuring water consumption events of 30 s or less, these events being common in residential customers. The research presented analyses of the metrological performance of 28 commercially available solid-state water meters from six different manufacturers in the presence of intermittent flows of various durations. The results show that the magnitude and dispersion of the error under intermittent flows is significantly larger in comparison to steady state flow conditions. The ultrasonic meters examined were more influenced by the intermittency than the electromagnetic meters., The work was partially funded by the Catedra UPV-FACSA-FOVASA de Agua, Residuos y Economia Circular. The authors are very grateful for the funding support. The authors would like to acknowledge the material and assistance received from FACSA during the development of the research.

This work presents the experimental demonstration of lossy mode resonance generation by means of aluminum doped zinc oxide thin-films. The use of such material may allow to optimize the performance of LMR-based sensors, obtaining good sensitivity at lower costs than other overlays, such as those including indium. The refractometric response of the fabricated devices is explored in different spectral regions. One refractometer working in the near infrared region was fabricated, obtaining a sensitivity of 2280 nm/RIU. A second refractometer working in the visible light spectrum was also fabricated. This second device allows to observe rough refractive index variations with the naked eye as a change of the color of the light propagating through the fiber, simplifying the setup needed for its use. This work was partly supported by the Spanish Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER) (TEC2016-79367-C2-2-R, TEC2016-78047-R ). The authors would also like to thanks the Spanish Ministry of Education (FPU15/05663 grant) and the Government of Navarra 0C023/024 BIOPTSENS and 64/2015 research funds. Dafne A. Piña-Azamar thanks CONACYT for scholarship assigned and PFCE-UAT 2016 project for the financial support to carry out this work.