Interdisciplinary Ph.D. Fellowships

[Marios Polycarpou]

REAL-TIME SPATIALLY-DISTRIBUTED DISINFECTANT CONTROL
IN WATER DISTRIBUTION NETWORKS USING NEURAL NETWORKS


The University of Cincinnati Earth System Science Program announces the 
availability of several Ph.D. graduate student fellowships, beginning 
Fall 1997. These Ph.D. fellowships are funded by the National Science
Foundation. Each fellow will receive a full tuition scholarship and a 
monthly stipend ($1450/month for 12 months), plus funds for research
supplies, travel to meetings, and support of a summer sabbatical at an 
off-campus location. Due to financial support requirements, all fellows 
must be either U.S. citizens or permanent residents. While the scope of 
research topics is broad and flexible, we are specifically seeking one or 
more individuals with an interest in studying spatially distributed real-time 
control of disinfectant residual in water distribution systems. 

The question we wish to answer is stated quite simply: How best to control 
the spatio-temporal distribution of disinfectant residual within a water 
distribution network? The actual problem is not simple, however, due to 
complex system dynamics and chemical kinetics. The looped distribution network
(i.e., it is not a spanning tree) is a multiple-input multiple-output, 
spatially extended dynamic system with significant time delays. The network 
hydraulics, which govern disinfectant transport on a system scale, are
driven by external consumer loads and time varying pump operations, and it 
is typical that network flows will change dramatically and frequently, both 
in magnitude and direction. Coupled with these dynamics are complex 
disinfectant kinetics that depend on the pipe material at a physical location,
the water source(s), and the type of disinfectant addition at the source(s) 
(multiple disinfectants are sometimes used). Further, the reactions with 
chlorine (the most common disinfectant) produce byproducts that evidence 
suggests are carcinogenic. This evidence has led to tightening lower and 
upper limits on acceptable chlorine concentrations within the network, and 
thus to a real need for more advanced control approaches and for a better 
understanding of disinfectant decay kinetics. 

Our plans for this work include the development and adaptation of 
control-theoretic approaches, including neural network methodologies,
for real-time spatially-distributed control of multiple simultaneous 
disinfectant additions. Activities that fall within the project scope 
include: 1) development of appropriate modeling and simulation methods, 
2) consideration of system robustness in the face of uncertain fluctuations 
in water demands, and 3) optimal location of disinfectant additions to 
minimize control effort. 

Applications are encouraged from individuals in any branch of engineering 
or the physical sciences; applicants should demonstrate a high degree of 
creativity along with strong quantitative and programming skills, and are 
expected to interact with chemists, electrical and environmental engineers, 
and utility personnel participating on the research team. For more information
including application materials, contact Prof. Jim Uber (Environ. Hydrology, 
513-556-3643, Jim.Uber at uc.edu) or Prof. Marios Polycarpou (Elec. & Comp. Eng. 
& Comp. Sci., 513-556-4763, Marios.Polycarpou at uc.edu). 



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*  Prof.  Marios  M. Polycarpou             |     TEL: (513) 556-4763    *    
*  University of Cincinnati                 |     FAX: (513) 556-7326    *    
*  Dept.  Electrical & Computer Engineering |                            *    
*  Cincinnati, Ohio 45221-0030              |  Email: polycarpou at uc.edu  *
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