75 research outputs found
Phase space measure concentration for an ideal gas
We point out that a special case of an ideal gas exhibits concentration of
the volume of its phase space, which is a sphere, around its equator in the
thermodynamic limit. The rate of approach to the thermodynamic limit is
determined. Our argument relies on the spherical isoperimetric inequality of
L\'{e}vy and Gromov.Comment: 15 pages, No figures, Accepted by Modern Physics Letters
Correlation or not correlation? This is the question in modeling residential water demand pulses
Published© 2013 The Authors. Published by Elsevier Ltd. This paper presents a comparison of two different modelling approaches for the generation of residential water demand pulses as Poisson processes. Both approaches are able to preserve the mean value of daily water demand. The main difference lies in the fact that the first considers the correlation between pulse durations and intensities whereas the second neglects it. Overall, the results of the applications aimed at reproducing the measured pulses in two households show that the increase in parameterization burden associated with taking correlation into account delivers a considerable improvement in the quality of model predictions
Forecasting domestic water consumption from smart meter readings using statistical methods and artificial neural networks
PublishedThis paper presents an artificial neural network-based model of domestic water consumption. The model is based on real-world data collected from smart meters, and represents a step toward being able to model real-time smart meter data. A range of input schemas are examined, including real meter readings and summary statistics derived from readings, and it is found that the models can predict some consumption but struggle to accurately match in cases of peak usage
Preserving duration-intensity correlation on synthetically generated water demand pulses
This paper proposes the application of three different methods for preserving the correlation between duration and intensity of synthetically generated water demand pulses. The first two methods, i.e., the Iman and Canover (1982) method and the Gaussian copula (Nelsen, 1999) respectively, are derived from the known statistical approaches, though they had never bee applied to the context of demand pulse generation. The third is a novel methodology developed in this work and is a variation in the Gaussian cupola approach. Applications carried out to reproduce the demand pulses measured in one household prove that the three methods are effective and applicable under general conditions
Paradigme de la régression polynomiale évolutionnaire multi-objectif pour la sélection de variables d'entrée pertinentes de modèles de qualité des eaux pluviales
Drinking water temperature around the globe : understanding, policies, challenges and opportunities
Water temperature is often monitored at water sources and treatment works; however, there is limited monitoring of the water temperature in the drinking water distribution system (DWDS), despite a known impact on physical, chemical and microbial reactions which impact water quality. A key parameter influencing drinking water temperature is soil temperature, which is influenced by the urban heat island effects. This paper provides critique and comprehensive summary of the current knowledge, policies and challenges regarding drinking water temperature research and presents the findings from a survey of international stakeholders. Knowledge gaps as well as challenges and opportunities for monitoring and research are identified. The conclusion of the study is that temperature in the DWDS is an emerging concern in various countries regardless of the water source and treatment, climate conditions, or network characteristics such as topology, pipe material or diameter. More research is needed, especially to determine (i) the effect of higher temperatures, (ii) a legislative limit on temperature and (iii) measures to comply with this limit
Drinking water temperature around the globe: Understanding, policies, challenges and opportunities
Water temperature is often monitored at water sources and treatment works; however, there is limited monitoring of the water temperature in the drinking water distribution system (DWDS), despite a known impact on physical, chemical and microbial reactions which impact water quality. A key parameter influencing drinking water temperature is soil temperature, which is influenced by the urban heat island effects. This paper provides critique and comprehensive summary of the current knowledge, policies and challenges regarding drinking water temperature research and presents the findings from a survey of international stakeholders. Knowledge gaps as well as challenges and opportunities for monitoring and research are identified. The conclusion of the study is that temperature in the DWDS is an emerging concern in various countries regardless of the water source and treatment, climate conditions, or network characteristics such as topology, pipe material or diameter. More research is needed, especially to determine (i) the effect of higher temperatures, (ii) a legislative limit on temperature and (iii) measures to comply with this limit
URCA!: scenari di cambiamento climatico, eventi pluviometrici di progetto e approccio partecipato per migliorare la resilienza urbana
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