3D model evolution of a leak based on GPR image interpretations

This paper presents some aspects of the time propagation of underground water leakage in controlled laboratory conditions using a drilled polyvinyl chloride (PVC) pipe and interpreting ground penetrating radar (GPR) images. GPR pre-processed images are interpreted for easy identification and extraction of surfaces and volumes of water leakage. Finally, the temporal evolution of a water leak is shown using 3D models based on interpretation of GPR images. Water volumes obtained using this approach can be easily observed by personnel who lack highly specialized training in the analysis of raw data. The results of this study are promising and can help develop techniques to validate non-destructive models for the identification, distribution, and prediction of water leaks in water supply systems using GPR.Part of this work has been developed under the support of an FPI (Formacion de Personal Investigador)-UPV (Universitat Politecnica de Valencia) scholarship granted to the second author by the Programa de Ayudas de Investigacion y Desarrollo (PAID) of the Universitat Politecnica de Valencia, and the support of Fundacion Carolina PhD, within its short stances scholarship program for the first author. The use of English in this paper has been revised by John Rawlins.Ocana-Levario, S.; Ayala Cabrera, D.; Izquierdo Sebastián, J.; Pérez García, R. (2015). 3D model evolution of a leak based on GPR image interpretations. Water Science and Technology: Water Supply. 15(6):1312-1319. doi:10.2166/ws.2015.093S1312131915

Caracterización de tuberías enterradas para redes de abastecimiento en servicio mediante el análisis de imágenes obtenidas con radar de subsuelo (Ground Penetrating Radar - GPR)

En este trabajo se evalúa la viabilidad del método propuesto de análisis de radargramas para la caracterización de los componentes del sistema de abastecimiento en servicio, con la realización de ensayos de laboratorio, empleando tuberías de diferentes características materiales en un entorno controlado.Ayala Cabrera, D. (2009). Caracterización de tuberías enterradas para redes de abastecimiento en servicio mediante el análisis de imágenes obtenidas con radar de subsuelo (Ground Penetrating Radar - GPR). http://hdl.handle.net/10251/1443

Hybrid optimization proposal for the design of collective on-rotation operating irrigation networks

[EN] Hybrid models have been used in many engineering applications in order to find better solutions and to reduce project costs. In this paper a methodology for the optimal design of collective working shift irrigation systems is proposed. The proposal is based on a hybrid model of optimization, which includes Linear Programming (LP) and Genetic Algorithms (GA). The method is applied to an irrigation network to check its effectiveness to minimize the total investment costs for pipelines. The results are compared to another hybrid model for optimization, which is based on Nonlinear Programming (NLP) and GA. The advantage of the developed method is a more cost effective design using discrete pipeline diameters. (C) 2016 Published by Elsevier Ltd.Thanks to the Technical University of Loja/Ecuador for funding the research, the Gestar group of investigation of the University of Zaragoza, Spain and to Dr. Andreas Fries.Lapo Pauta, CM.; Pérez García, R.; Izquierdo Sebastián, J.; Ayala Cabrera, D. (2017). Hybrid optimization proposal for the design of collective on-rotation operating irrigation networks. Procedia Engineering. 186:530-536. doi:10.1016/j.proeng.2017.03.266S53053618

Water supply system component evaluation from GPR radargrams using a multi-agent approach

This paper uses a multi-agent approach as a quick and easy tool for the interpretation and analysis of the characteristics of Water Supply System (WSS) components when working on a collection of Ground Penetrating Radar (GPR) survey files. The multi-agent algorithm proposed in this paper has been developed in Matlab and is based on Game Theory. The input is the result of the GPR radargram survey and the output consists of the agent scores in the game proposed in this paper. Useful information can be gained by interpreting the columns of the output matrix that describe the agents’ movements, together with the associated racing times. In effect, this analysis enables a simple determination of the electromagnetic properties of the underground system and provides an accurate classification of these properties. The results of this agent racing algorithm are promising, since it groups, and consequently, decreases the number of points that make up the initial radargrams; while at the same time preserving its main properties, and enabling clearer views of pipes and a better identification of the components in WSS.This work has been supported by project IDAWAS, DPI2009-11591, of the Direccion General de Investigacion of the Ministerio de Ciencia e Innovacion of Spain, ACOMP/2011/188 of the Conselleria de Educacion of the Generalitat Valenciana, and the FPI-UPV scholarship granted to the first author by the Programa de Ayudas de Investigacion y Desarrollo (PAID) of the Universitat Politecnica de Valencia.Ayala Cabrera, D.; Izquierdo Sebastián, J.; Montalvo Arango, I.; Pérez García, R. (2013). Water supply system component evaluation from GPR radargrams using a multi-agent approach. Mathematical and Computer Modelling. 57(7-8):1927-1932. https://doi.org/10.1016/j.mcm.2011.12.034S19271932577-

Probabilistic maps for buried pipes location based on GPR images

In this work, statistical methodologies are used to generate automatic probabilistic maps of pipe layouts in water supply systems (WSS) based on street surveys using ground penetrating radar (GPR). Probabilistic maps are based on the analysis of GPR images along with a multi-agent generation of pseudo-random walks, and a process to discard areas with less probability of pipe existence. This is an iterative procedure that we have integrated into a system that produces GPR sampling walks, and eventually set up a reliable location map of buried pipes. As a result the survey time is optimized and the amount of data needed to conduct records of the components of WSS is minimized.Ayala Cabrera, D.; Izquierdo Sebastián, J.; Pérez García, R.; Ocaña Levario, SJ. (2014). Probabilistic maps for buried pipes location based on GPR images. International Journal of Complex Systems in Science. 4(1):27-34. http://hdl.handle.net/10251/57599S27344

Label Propagation Algorithm Based Methodology for Water Supply Networks Sectorization

The increasing pressure over water resources has raised the need to establish procedures to efficiently manage water supply networks (WSN). An example of such procedures is the sectorization of networks either by installing valves (closed) or by sectioning pipes. This work presents a WSN sectorization method based on a combination of operational criteria with a so called label propagation algorithm. The method has proven to be appropriate to sectorize WSN dependent of a trunk where the number of sectors is a priori unknown.Campbell Gonzalez, E.; Ayala Cabrera, D.; Izquierdo Sebastián, J.; Pérez García, R.; Tavera, M. (2014). Label Propagation Algorithm Based Methodology for Water Supply Networks Sectorization. International Journal of Complex Systems in Science. 4(1):35-39. http://hdl.handle.net/10251/57596S35394

Piezometric error derived from some demand lumped models in water distribution

Allocation of the internal demand in a line to the end nodes of the line may help reduce the size of the mathematical model of a water distribution network (WDN). Such a reduction is desirable as it allows hydraulic simulations at a lower computational cost. Moreover, this reduction is inevitable in the case of WDN models of large cities, due to its size, which require huge amounts of computational resources. However, such simplified models are not at zero cost, since they produce various errors in the calculations. In this contribution we provide a calculation mechanism that allows the engineers responsible for the hydraulic model of a WDN to know the errors in terms of piezometric head produced by allocating the internal demands of a line to the end nodes of the line.Izquierdo Sebastián, J.; Campbell Gonzalez, E.; Montalvo Arango, I.; Pérez García, R.; Ayala Cabrera, D. (2014). Piezometric error derived from some demand lumped models in water distribution. International Journal of Complex Systems in Science. 4(1):17-20. http://hdl.handle.net/10251/57597S17204

Multi-agent simulation of hydraulic transient equations in pressurized systems

Computational modeling pervades virtually every industrial process. By using numerical representations of the behavior of elements that constitute a system it is possible to obtain efficient and safe designs. Moreover, system operation can be better defined by using such models, thus enabling greater reliability and control. In this paper the use of agents to solve the equations describing fast transients in water networks is investigated. As the simulation of hydraulic transients in pressurized systems is a naturally distributed problem, the authors argue that a multi-agent based system is very suitable for the solution of this complex engineering phenomenon. A hybrid solution is built by deploying agents to work with sets of equations describing hydraulic transient behavior in pipeline systems. The details necessary to assemble a complete and lubricated machine to model the complex phenomenon of hydraulic transients in pressurized systems are described. This research develops a platform that constitutes an efficient and versatile tool of great interest for water supply managers when analyzing water hammer effects in their networks.Izquierdo Sebastián, J.; Montalvo Arango, I.; Pérez García, R.; Ayala Cabrera, D. (2015). Multi-agent simulation of hydraulic transient equations in pressurized systems. Journal of Computing in Civil Engineering. 04015071:1-14. doi:10.1061/(ASCE)CP.1943-5487.0000549S1140401507