Papers by Raziyeh Farmani
Water Science and Technology, Feb 19, 2018
Resilience building commonly focuses on attributes such as redundancy. Whilst this may be effecti... more Resilience building commonly focuses on attributes such as redundancy. Whilst this may be effective in some cases, provision of specific attributes does not guarantee resilient performance and research is required to determine the suitability of such approaches. This study uses 250 combined sewer system virtual case studies to explore the effects of two attribute-based interventions (increasing distributed storage and reducing imperviousness) on performance-based resilience measures. These are found to provide improvement in performance under system failure in the majority of case studies, but it is also shown that attribute-based intervention development can result in reduced resilience.
Water Research, Dec 1, 2016
Evaluating and enhancing resilience in water infrastructure is a crucial step towards more sustai... more Evaluating and enhancing resilience in water infrastructure is a crucial step towards more sustainable urban water management. As a prerequisite to enhancing resilience, a detailed understanding is required of the inherent resilience of the underlying system. Differing from traditional risk analysis, here we propose a global resilience analysis (GRA) approach that shifts the objective from analysing multiple and unknown threats to analysing the more identifiable and measurable system responses to extreme conditions, i.e. potential failure modes. GRA aims to evaluate a system's resilience to a possible failure mode regardless of the causal threat(s) (known or unknown, external or internal). The method is applied to test the resilience of four water distribution systems (WDSs) with various features to three typical failure modes (pipe failure, excess demand, and substance intrusion). The study reveals GRA provides an overview of a water system's resilience to various failure modes. For each failure mode, it identifies the range of corresponding failure impacts and reveals extreme scenarios (e.g. the complete loss of water supply with only 5% pipe failure, or still meeting 80% of demand despite over 70% of pipes failing).GRA also reveals that increased resilience to one failure mode may decrease resilience to another and increasing system capacity may delay the system's recovery in some situations. It is also shown that selecting an appropriate level
A comprehensive assessment of resilience requires consideration of system performance under excep... more A comprehensive assessment of resilience requires consideration of system performance under exceptional conditions, including those that are unforeseen, and can be achieved using a previously developed methodology called 'global resilience analysis' (GRA). GRA captures the effects of both probable and highly improbable (unknown probability) system failures and requires no knowledge of threats. Here, a simple, user-friendly tool that automates the simulations required for GRA of a water distribution system and assists comprehension of the results is presented. Provided the user can supply an Epanet .inp file for the system and that this contains demand data (an understanding of Epanet and system failure modelling is not necessary), the tool can be used to quantify the resilience of the system to pipe failure, pump failure, demand increase and contaminant intrusion. An interactive results explorer allows the user to easily identify critical system components based on the selected level of service type and failure measure (e.g. pressure, supply or contamination and failure magnitude or duration). A map of the network can be used to either color-code components based on their criticality in a single component failure analysis or to identify specific combinations of components which result in the greatest level of service failure magnitude or duration when failed simultaneously. 'Stress-strain' type response curves can also be automatically generated and key findings automatically extracted. Additionally, the tool enables systems to be compared on a like-for-like basis, enabling the effects of proposed interventions on resilience to be quantified and visualized.
Water Research, Aug 1, 2021
Complexity in water distribution systems (WDSs) poses a challenge for analysis and management of ... more Complexity in water distribution systems (WDSs) poses a challenge for analysis and management of the systems. To reduce the complexity, the recent development of complex network science provides a system decomposition technique that converts a complex WDS with a large number of components into a simple system with a set of interconnected modules. Each module is a subsystem with stronger internal connections than external connections. Thus far, the topological features of the modular structure in WDS have been extensively studied but not the behavioural features, e.g. the hydraulic interdependencies among modules. Therefore, this paper aims to quantitatively measure and graphically visualize the module interdependency in WDSs, which helps understanding the behavioural complexity of WDSs and thus various WDS analyses, such as pipe maintenance, model calibration, rehabilitation, and District Metered Areas planning. Specifically, this study first identifies the WDS's modular structure then measures how changes in the state of one module (i.e. any single pipe
Water Research, Oct 1, 2019
Where a licence is displayed above, please note the terms and conditions of the licence govern yo... more Where a licence is displayed above, please note the terms and conditions of the licence govern your use of this document. When citing, please reference the published version. Take down policy While the University of Birmingham exercises care and attention in making items available there are rare occasions when an item has been uploaded in error or has been deemed to be commercially or otherwise sensitive.
Research for all, 2020
This article has been peer-reviewed through the journal's standard double-blind peer review, wher... more This article has been peer-reviewed through the journal's standard double-blind peer review, where both the reviewers and authors are anonymized during review.
Global challenges, Jun 17, 2016
Global threats such as climate change, population growth, and rapid urbanization pose a huge futu... more Global threats such as climate change, population growth, and rapid urbanization pose a huge future challenge to water management, and, to ensure the ongoing reliability, resilience and sustainability of service provision, a paradigm shift is required. This paper presents an overarching framework that supports the development of strategies for reliable provision of services while explicitly addressing the need for greater resilience to emerging threats, leading to more sustainable solutions. The framework logically relates global threats, the water system (in its broadest sense), impacts on system performance, and social, economic, and environmental consequences. It identifies multiple opportunities for intervention, illustrating how mitigation, adaptation, coping, and learning each address different elements of the framework. This provides greater clarity to decision makers and will enable better informed choices to be made. The framework facilitates four types of analysis and evaluation to support the development of reliable, resilient, and sustainable solutions: "top-down," "bottom-up," "middle based," and "circular" and provides a clear, visual representation of how/when each may be used. In particular, the potential benefits of a middle-based analysis, which focuses on system failure modes and their impacts and enables the effects of unknown threats to be accounted for, are highlighted. The disparate themes of reliability, resilience and sustainability are also logically integrated and their relationships explored in terms of properties and performance. Although these latter two terms are often conflated in resilience and sustainability metrics, the argument is made in this work that the performance of a reliable, resilient, or sustainable system must be distinguished from the properties that enable this performance to be achieved. Impact Statement: Water management faces major challenges over the coming decades, with existing social, ecological, and technical water subsystems subject to emerging global threats such as climate change, urbanization, and depletion of resources. Current methods may be able to deal with these threats individually; however, recent experiences have revealed serious problems, and, without new ideas and approaches, levels of service will be challenged significantly by future change. This research, therefore, provides a framework that addresses the need to provide safe (reliable) water management that is also resilient and sustainable in the face of emerging threats and highlights opportunities for intervention. In doing so, it aims to provide greater clarity to decision makers, allowing better informed choices to be made. It also connects the additional global challenges of climate change, energy, food production, agriculture, and health, all of which may be threats to water management and/or consequences of water system failure.
Water Research, 2021
Complexity in water distribution systems (WDSs) poses a challenge for analysis and management of ... more Complexity in water distribution systems (WDSs) poses a challenge for analysis and management of the systems. To reduce the complexity, the recent development of complex network science provides a system decomposition technique that converts a complex WDS with a large number of components into a simple system with a set of interconnected modules. Each module is a subsystem with stronger internal connections than external connections. Thus far, the topological features of the modular structure in WDS have been extensively studied but not the behavioural features, e.g. the hydraulic interdependencies among modules. Therefore, this paper aims to quantitatively measure and graphically visualize the module interdependency in WDSs, which helps understanding the behavioural complexity of WDSs and thus various WDS analyses, such as pipe maintenance, model calibration, rehabilitation, and District Metered Areas planning. Specifically, this study first identifies the WDS's modular structure then measures how changes in the state of one module (i.e. any single pipe
Water Research, 2020
This document consists of 37 pages, 25 Tables and 30 Figures.
Journal of Water Resources Planning and Management, 2020
The paper presents the results of the Battle of Post-Disaster Response and Restoration (BPDRR), p... more The paper presents the results of the Battle of Post-Disaster Response and Restoration (BPDRR), presented in a special session at the 1 st International WDSA/CCWI Joint Conference, held in Kingston, Ontario, in July 2018. The BPDRR problem focused on how to respond and restore water service after the occurrence of five earthquake scenarios that cause structural damage in a water distribution system. Participants were required to propose a prioritization schedule to fix the damages of each scenario while following restrictions on visibility/non visibility of damages. Each team/approach was evaluated against six performance criteria that included: 1) Time without supply for hospital/firefighting, 2) Rapidity of recovery, 3) Resilience loss, 4) Average time of no user service, 5) Number of users without service for 8 consecutive hours, and 6) Water loss. Three main types of approaches were identified from the submissions: 1) General purpose metaheuristic algorithms, 2) Greedy algorithms, and 3) Ranking-based prioritizations. All three approaches showed potential to solve the challenge efficiently. The results of the participants showed that, for this network, the impact of a largediameter pipe failure on the network is more significant than several smaller pipes failures. The location of isolation valves and the size of hydraulic segments influenced the resilience of the system during emergencies. On average, the interruptions to water supply (hospitals and firefighting) varied considerably between solutions and emergency scenarios, highlighting the importance of private water storage for emergencies. The effects of damages and repair work were more noticeable during the peak demand periods (morning and noontime) than during the low-flow periods; and tank storage helped to preserve functionality of the network in the first few hours after a simulated event.
Production Planning & Control, 2019
Addressing the intersection of two important emerging research areas, re-distributed manufacturin... more Addressing the intersection of two important emerging research areas, re-distributed manufacturing (RDM) and the food-energy-water (FEW) nexus, this work combines insights from engineering, business and policy perspectives and explores opportunities and challenges towards a more localized and sustainable food system. Analysis centred on two specific food products, namely bread and tomato paste reveals that the feasibility and potential of RDM vary with the type of food product and the supply chain (SC) components. Physically, energy efficiency, water consumption and reduction of waste and carbon footprint may be affected by scale and location of production activities and potentials of industrial symbiosis. From the business perspective, novel products, new markets and new business models are expected in order for food RDM to penetrate within the established food industry. Studies on policies, through the lens of public procurement, call for solid evidence of envisioned environmental, social and economic benefits of a more localized food system. An initial integrated framework is proposed for understanding and assessing food RDM and the FEW nexus.
Water Research, 2016
Evaluating and enhancing resilience in water infrastructure is a crucial step towards more sustai... more Evaluating and enhancing resilience in water infrastructure is a crucial step towards more sustainable urban water management. As a prerequisite to enhancing resilience, a detailed understanding is required of the inherent resilience of the underlying system. Differing from traditional risk analysis, here we propose a global resilience analysis (GRA) approach that shifts the objective from analysing multiple and unknown threats to analysing the more identifiable and measurable system responses to extreme conditions, i.e. potential failure modes. GRA aims to evaluate a system's resilience to a possible failure mode regardless of the causal threat(s) (known or unknown, external or internal). The method is applied to test the resilience of four water distribution systems (WDSs) with various features to three typical failure modes (pipe failure, excess demand, and substance intrusion). The study reveals GRA provides an overview of a water system's resilience to various failure modes. For each failure mode, it identifies the range of corresponding failure impacts and reveals extreme scenarios (e.g. the complete loss of water supply with only 5% pipe failure, or still meeting 80% of demand despite over 70% of pipes failing).GRA also reveals that increased resilience to one failure mode may decrease resilience to another and increasing system capacity may delay the system's recovery in some situations. It is also shown that selecting an appropriate level
Water Supply, 2015
In future cities, urban water systems (UWSs) should be designed not only for safe provision of se... more In future cities, urban water systems (UWSs) should be designed not only for safe provision of services but should also be resilient to emerging or unexpected threats that lead to catastrophic system failure impacts and consequences. Resilience can potentially be built into UWSs by implementing a range of strategies, for example by embedding redundancy and flexibility in system design, or by rehabilitation to increase their ability to maintain acceptable customer service levels during unexpected system failures. In this work, a new resilience analysis is carried out to investigate the performance of a water distribution system (WDS) and an urban drainage system (UDS) during pipe failure scenarios. Using simplified synthetic networks, the effect of implementing adaptation (resilient design) strategies on minimising the loss of system functionality and cost of UWSs is investigated. Study results for the WDS case study show that the design strategy in which flexibility is enhanced ensu...
Journal of Water Resources Planning and Management, 2016
This paper proposes the application of three different methods for preserving the correlation bet... more 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 method and the Gaussian copula respectively, are derived from known statistical approaches, though they had never been 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 copula approach. Poisson models fitted with the methods are applied to reproduce the measured pulses in one household, with parameters being obtained with the method of moments. Comparisons are made with another method previously proposed in the scientific literature, showing that the three methods have similar effectiveness and are applicable under more general conditions.
Twin-Hierarchy Decomposition for Optimal Design of Water Distribution Systems
Journal of Water Resources Planning and Management, 2016
AbstractThis paper proposes a methodology to decompose water distribution systems (WDSs) into a t... more AbstractThis paper proposes a methodology to decompose water distribution systems (WDSs) into a twin-hierarchy pipeline structure consisting of backbone mains and community feeders. The method has three steps: (1) clustering analysis; (2) vulnerability analysis; and (3) identification of backbone mains and community feeders. After decomposition, analysis of a whole complex WDS could be simplified to that of smaller subsystems formed by either backbone mains or community feeders. The method enables the analysis of all communities independently without physical division of the WDS. It is applied to an optimal-design problem of the C-Town network defined in the literature. The problem is to find the best tradeoff between reducing background leakage and minimizing capital and operational costs. The final solution has a total annual cost of 1.19 million Euro with 54% operational costs and 46% capital costs, respectively. The decomposition process is also consistent with engineering practice on leakage control ...
Procedia Engineering, 2015
This paper presents a comparison of two different modelling approaches for the generation of resi... more 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.
Procedia Engineering, 2015
This paper proposes the application of three different methods for preserving the correlation bet... more 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 been 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.
Procedia Engineering, 2015
This paper presents an artificial neural network-based model of domestic water consumption. The m... more This 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.
Building resilience in urban water systems for cities of the future
Journal of Water Resources Planning and Management, 2015
This paper proposes the application of three different methods for preserving the correlation bet... more 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 method and the Gaussian copula respectively, are derived from known statistical approaches, though they had never been 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 copula approach. Poisson models fitted with the methods are applied to reproduce the measured pulses in one household, with parameters being obtained with the method of moments. Comparisons are made with another method previously proposed in the scientific literature, showing that the three methods have similar effectiveness and are applicable under more general conditions.
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Papers by Raziyeh Farmani