Scientific Results

This catalogue is obtained by conducting a systematic literature review of scientific studies and reviews related to monitoring, forecasting, and simulating the inland water cycle. The analysis maps scientific expertise across research groups and classifies findings by the type of inland water studied, application focus, and geographical scope. A gap analysis will identify missing research areas and assess their relevance to policymaking.

ID ▲	Type	Year	Authors	Title	Venue/Journal	DOI	Abstract
publications-4261	article	2018	Tao, Fei and Tao, Fei and Cheng, Jiangfeng and Cheng, Jiangfeng and Qi, Qinglin and Qi, Qinglin and Zhang, Meng and Zhang, Meng and Zhang, Meng and Zhang, He and Zhang, He and Sui, Fangyuan and Sui, Fangyuan	Digital twin-driven product design, manufacturing and service with big data	The International Journal of Advanced Manufacturing Technology	10.1007/s00170-017-0233-1	Nowadays, along with the application of new-generation information technologies in industry and manufacturing, the big data-driven manufacturing era is coming. However, although various big data in the entire product lifecycle, including product design, manufacturing, and service, can be obtained, it can be found that the current research on product lifecycle data mainly focuses on physical products rather than virtual models. Besides, due to the lack of convergence between product physical and virtual space, the data in product lifecycle is isolated, fragmented, and stagnant, which is useless for manufacturing enterprises. These problems lead to low level of efficiency, intelligence, sustainability in product design, manufacturing, and service phases. However, physical product data, virtual product data, and connected data that tie physical and virtual product are needed to support product design, manufacturing, and service. Therefore, how to generate and use converged cyber-physical data to better serve product lifecycle, so as to drive product design, manufacturing, and service to be more efficient, smart, and sustainable, is emphasized and investigated based on our previous study on big data in product lifecycle management. In this paper, a new method for product design, manufacturing, and service driven by digital twin is proposed. The detailed application methods and frameworks of digital twin-driven product design, manufacturing, and service are investigated. Furthermore, three cases are given to illustrate the future applications of digital twin in the three phases of a product respectively.
publications-4262	article	1997	Espey, Molly and Espey, M. and Espey, Molly and Espey, James A. and Espey, J. and Shaw, W. Douglass and Shaw, W. D.	PRICE ELASTICITY OF RESIDENTIAL DEMAND FOR WATER: A META?ANALYSIS	Water Resources Research	10.1029/97wr00571	Meta-analysis is used to determine if there are factors that systematically affect price elasticity estimates in studies of residential water demand in the United States. An econometric model is estimated, using price elasticity estimates from previous studies as the dependent variable. Explanatory variables include functional form, cross-sectional versus time series, water price specification, rate structure, location, season, and estimation technique. Inclusion of income, rainfall, and evapotranspiration are all found to influence the estimate of the price elasticity. Population density, household size, and temperature do not significantly influence the estimate of the price elasticity. Pricing structure and season are also found to significantly influence the estimate of the price elasticity.
publications-4263	article	2000	Barreteau, Olivier and Barreteau, Olivier and Bousquet, FranΓ§ois and Bousquet, FranΓ§ois	SHADOC : a multi-agent model to tackle viability of irrigated systems	Annals of Operations Research	10.1023/a:1018908931155	The viability of irrigated systems in the Senegal River Valley is being brought into question today due to their underβ€utilization. We assume that their viability depends largely on the way their different components behave and interact. We therefore sought to examine in greater depth today's knowledge of the structure of these systems and activities performed within them. This led to the development of a multiβ€agent system model, a kind of virtual irrigated system, with a special focus on rules in use for access to credit, water allocation and cropping season assessment as well as organization and coordination of farmers. The purpose of this paper is to show how this kind of tool is relevant to the study of irrigated systems' viability. As an example it is used to examine the influence of existing social networks on the viability of irrigated systems. Copyright Kluwer Academic Publishers 2000
publications-4264	article	2003	Parker, Dawn C. and Parker, Dawn C. and Manson, Steven M. and Manson, Steven M. and Janssen, Marco A. and Janssen, Marco A. and Hoffmann, Matthew J. and Hoffmann, Matthew J. and Hoffmann, Matthew J. and Deadman, Peter and Deadman, Peter	Multi-Agent Systems for the Simulation of Land-Use and Land-Cover Change: A Review	Annals of The Association of American Geographers	10.1111/1467-8306.9302004	This paper presents an overview of multi-agent system models of land-use/cover change (MAS/LUCC models). This special class of LUCC models combines a cellular landscape model with agent-based representations of decisionmaking, integrating the two components through specification of interdependencies and feedbacks between agents and their environment. The authors review alternative LUCC modeling techniques and discuss the ways in which MAS/LUCC models may overcome some important limitations of existing techniques. We briefly review ongoing MAS/LUCC modeling efforts in four research areas. We discuss the potential strengths of MAS/LUCC models and suggest that these strengths guide researchers in assessing the appropriate choice of model for their particular research question. We find that MAS/LUCC models are particularly well suited for representing complex spatial interactions under heterogeneous conditions and for modeling decentralized, autonomous decision making. We discuss a range of possible roles for MAS/LUCC models, from abstract models designed to derive stylized hypotheses to empirically detailed simulation models appropriate for scenario and policy analysis. We also discuss the challenge of validation and verification for MAS/LUCC models. Finally, we outline important challenges and open research questions in this new field. We conclude that, while significant challenges exist, these models offer a promising new tool for researchers whose goal is to create fine-scale models of LUCC phenomena that focus on human-environment interactions.
publications-4265	article	2003	Berry, Jonathan W. and Fleischer, Lisa and Hart, William E. and Phillips, Cynthia A.	Sensor Placement in Municipal Water Networks		10.1061/40685(2003)40	In this paper we present a model for optimizing the placement of sensors in municipal water networks to detect maliciously-injected contaminants. Optimal sensor placement is required to ensure an adequate coverage of the network's flow for detection and remediation of contaminants. There are many possible objectives that could be formulated for optimal sensor placement, reflecting various costs and risks of an attack on a network. Previous work has focused on detection before a given volume of water has been consumed and detection within a given time limit. Additionally, Tryby et al. present related work on the placement of disinfectant booster station. We consider a sensor placement formulation for which optimal sensor configurations minimize the expected fraction of the population that is at risk for an attack. We model an attack as the release of a large volume of harmful contaminant at a single point in the network with a single injection. For any particular attack, we assume that all points "downstream" of the release point (connected by a set of directed edges) can be contaminated. In general, we do not know a priori where this attack will occur, so our objective is to place sensors to provide a compromise solution across a set of weighted attack scenarios.
publications-4266	article	2003	LeChevallier, Mark W. and LeChevallier, Mark W. and Gullick, Richard W. and Gullick, Richard W. and Karim, Mohammad Rezaul and Karim, Mohammad R. and Friedman, Melinda and Friedman, Melinda J. and Funk, James E. and Funk, James E.	The potential for health risks from intrusion of contaminants into the distribution system from pressure transients	Journal of Water and Health	10.2166/wh.2003.0002	The potential for public health risks associated with intrusion of contaminants into water supply distribution systems resulting from transient low or negative pressures is assessed. It is shown that transient pressure events occur in distribution systems; that during these negative pressure events pipeline leaks provide a potential portal for entry of groundwater into treated drinking water; and that faecal indicators and culturable human viruses are present in the soil and water exterior to the distribution system. To date, all observed negative pressure events have been related to power outages or other pump shutdowns. Although there are insufficient data to indicate whether pressure transients are a substantial source of risk to water quality in the distribution system, mitigation techniques can be implemented, principally the maintenance of an effective disinfectant residual throughout the distribution system, leak control, redesign of air relief venting, and more rigorous application of existing engineering standards. Use of high-speed pressure data loggers and surge modelling may have some merit, but more research is needed.
publications-4267	article	2004	Uber, James G. and Janke, Robert and Murray, Regan and Meyer, Philip D.	Greedy Heuristic Methods for Locating Water Quality Sensors in Distribution Systems		10.1061/40737(2004)481	Monitoring and surveillance systems for drinking water distribution networks are intended to provide real time warning of drinking water contamination events and mitigate their public health consequences. Drinking water distribution networks often serve large populations over vast areas. There exist a large number of access points where contaminants could be introduced, and these are spread throughout the service area. Transport of contaminants from these access points to consumers would occur through a multitude of pathways, and be dominated by water flows that change magnitude and direction in response to frequent changes in water use and system operation. The above features of drinking water distribution networks dictate that design of a successful monitoring and surveillance system is comprised of three interrelated sub-tasks:
publications-4268	article	2005	Ostfeld, Avi and Salomons, Elad	Securing Water Distribution Systems Using Online Contamination Monitoring	Journal of Water Resources Planning and Management	10.1061/(asce)0733-9496(2005)131:5(402)	The events of September 11, 2001 in the United States have brought to the fore the problem of drinking water distribution systems security. As a water distribution system is spatially diverse, limiting physical access to all components is practically impossible. Deliberate intrusions of contaminants directly into tanks, treatment plants, or through connecting devices is considered one of the most serious terrorist threats. An effective means of reducing this threat is online contamination monitoring. This paper extends previous work of the writers for optimal allocation of monitoring stations to secure drinking water distribution systems against deliberate contamination intrusions. The current methodology takes explicitly into account the randomness of the flow rate of the injected pollutants, the randomness in consumerβ€™s demands, and the detection sensitivity and response time of the monitoring stations. The objective is to determine the optimal location of a set of monitoring stations aimed at detecting...
publications-4269	article	2007	Greyvenstein, B. and Greyvenstein, B. and van Zyl, J. E. and van Zyl, J. E.	An experimental investigation into the pressure - leakage relationship of some failed water pipes	Journal of Water Supply Research and Technology-aqua	10.2166/aqua.2007.065	This paper reports on an experimental study that was conducted to measure the leakage exponents of different types of leak openings (holes, corrosion holes, and longitudinal and circumferential cracks) and pipe materials (asbestos cement, mild steel and uPVC). A number of failed pipes taken from the Johannesburg water distribution system were tested, as well as a number of pipes with artificially induced leaks. The results of the study confirmed that leakage exponents can be significantly higher than the theoretical value of 0.5. While leakage exponents for round holes were close to 0.5, the values for corrosion holes varied between 0.67 and 2.30, for longitudinal cracks between 0.79 and 1.85, and for circumferential cracks between 0.41 and 0.52. Conclusions include that the highest leakage exponents were found in corroded steel pipes and that under certain circumstances, leakage exponents can be less than 0.5.
publications-4270	article	2007	Hart, Darren M. and Hart, David and McKenna, Sean Andrew and McKenna, Sean A. and Klise, Katherine A. and Klise, Katherine A. and Cruz, Victoria and Cruz, Victoria and Wilson, M. P. and Wilson, Mark and Wilson, M. and Wilson, M.	CANARY: A Water Quality Event Detection Algorithm Development Tool.		10.1061/40927(243)517	The detection of anomalous water quality events has become an increased priority for distribution systems, both for quality of service and security reasons. Because of the high cost associated with false detections, both missed events and false alarms, algorithms which aim to provide event detection and need to be evaluated and configured properly. CANARY has been developed to provide both real-time, and off-line analysis tools to aid in the development of these algorithms, allowing algorithm developers to focus on the algorithms themselves, rather than on how to read in data and drive the algorithms. Among the features to be discussed and demonstrated are: 1) use of a standard data exchange format for input and output of water quality and operations data streams; 2) the ability to "plug in" various water quality change detection algorithms, both in MATLABΒ® and compiled library formats for testing and evaluation by using a well defined interface; 3) an "operations mode" to simulate what a utility operator will receive; 4) side-by-side comparison tools for different evaluation metrics, including ROC curves, time to detect, and false alarm rates. Results will be shown using three algorithms previously developed using test and real-life data sets.