Another one...

SENSOR PLACEMENT IN MUNICIPAL WATER NETWORKS
By Jonathan W. Berry; Lisa Fleischer; William E. Hart; Cynthia A. Phillips; and Jean-Paul Watson

Summary

The findings presented in this paper were to address the concerns of the U.S. Environmental Protection Agency that most of the U.S. water supply is highly susceptible to contamination (either accidental or intentional) and that any contamination would go largely undetected, which would place a high risk on public health. The authors present a model that optimizes the placement of sensors in municipal networks to detect maliciously injected contaminants (Berry 237). The LP method utilized is a mixed-integer program that seeks to minimize the fraction of the population at risk. Three separate networks were tested (two fictional networks taken from EPANET and one real-life network). The result of the research is an MIP model that effectively solves large-scale sensor-placement problems (so claims the authors, although the effectiveness and validity of the findings can always be disputed). It was also demonstrated that noise or uncertainty in the data had very little impact on the results of the analysis.

Discussion

Although several assumptions made in the paper were a little unrealistic (constant flow path and velocity, no variance over time and space of contaminant concentration, etc.), I would deem the overall work both viable and reasonable considering the purpose of the research. I found the paper to be a good follow-up to the previous discussion paper.
The authors speak on how this knowledge will be easily transferable to real-world large-scale sensor-placement problems. I wonder how many public water supply companies 1) are aware of this research; and 2) would know how to go about implementing this work if they did… maybe they could hire us!