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45603-AC9
Instrumentation Network Design and Retrofit

Miguel Bagajewicz, University of Oklahoma

PROJECT ACTIVITIES
The original goals of the project were:
a)      New network performance measures: residual reliability, and accuracy of estimators, which will help overcome practical problems in implementing current design methods.
b)      An unconstrained optimization model, which relates all sensor network properties to the value of the information they produce and contrasts it with cost.
c)      Inclusion of financial risk management in the problem.

 Revised Scope of Work (Due to reduction from three years to two years)
The original proposal included:
-          New Robustness measures (Accuracy and residual reliability): Of these, we will leave out the residual reliability, but will keep the work on accuracy.
-          Unconstrained Optimization and Financial Risk: This part will consider the linear cases only. The non-linear systems will be taken out.

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AN EXTENSION WAS REQUESTED AND GRANTED
REPORT
The major outcomes are:
a)      A paper outlining stochastic accuracy calculations:
·         Bagajewicz  M. and DuyQuang Nguyen. Stochastic-Based Accuracy of Data Reconciliation Estimators for Linear Systems. Computers and Chemical Engineering, 32, 6, 1257-1269 (2008) .
b)      A conference paper outlining stochastic accuracy calculations:
·         Bagajewicz Miguel, DuyQuang Nguyen Tanth  and Sanjay Kumar Sugumar. New Method for Sensor Network Design. Proceedings of ESCAPE 18, Lyon, France, June 2008.   
c)      A full paper on the design of sensor networks using precision goals (not accuracy)  is in press
·      DuyQuang Nguyen and M. Bagajewicz. Design of Nonlinear Sensor Networks for Process Plants. Industrial and  Engineering Chemistry Research (2007).
d)      A paper on the impact of maintenance on accuracy was submitted.  Positive reviews came back.
·          Nguyen Tanth DuyQuang and M. Bagajewicz. On the Impact of Sensor Maintenance Policies on Stochastic-Based Accuracy. Computers and Chemical Engineering.
e)      Two papers in preparation:.
·         Nguyen, DuyQuang, M. Bagajewicz and Sanjay Kumar Sugumar Software Accuracy based Linear and Nonlinear Sensor Network Design and Upgrade.  
·         Sanjay Kumar Sugumar, DuyQuang Nguyen and M. Bagajewicz. Reliability and Accuracy-Based linear and Nonlinear sensor networks.    
f)       The code for incorporating accuracy calculations to the existing sensor network design code has been finished and we are adding reliability. This is more than the declared goal.
g)      Work is underway to finish the Economic value of information work and the financial risk considerations.
h)      Work is also underway on approximate methods (use of Genetic Algorithms and other techniques) to reduce computational time. We will explore parallel computing schemes.

Summary of Project Findings
·         Stochastic accuracy calculations were made for linear cases and was extended to non-linear cases.
·         The code to incorporate stochastic accuracy to sensor network design is finished.  Reliability is being added. The major finding here is that reliability as well as residual reliability can be covered by stochastic accuracy. However, stochastic accuracy takes too much time.
Personnel
 As it is explained below, the project employed one existing student (DuyQuang Nguyen) , funded from other sources (the author of the papers cited above), hired one student (Aravinda Buddhala), who after 3 months left, and later hired a student (Sanjay Kumar Sugumar), who started in August 15, 2007. Sanjay has proven to be a weak student so we had to have  DuyQuang Nguyen help. He has now left the project.  
The extension granted will allow the project goals to be accomplished.

OUTREACH ACTIVITIES

The PI and his group engaged in a number of dissemination activities.
-          We made a presentation at the Texas Tech University Control Consortium in April 2007.
-          A paper was presented at the Inter American Conference of Chemical Engineering held in Buenos Aires, October 2006.    
·         XII Inter-American Congress of Chemical Engineering. October, 2006. Buenos Aires, Argentina. Cost Benefit Analysis of Instrument Maintenance Policies and Data Reconciliation Related to Plant Data Accuracy. DuyQuang Nguyen and M. Bagajewicz
-          We submitted papers to the AIChE Annual Conference to be held in November 2007 in Salt Lake City.
·         AIChE Annual Meeting. Salt Lake City, UT (2007). Realizing Smart Plants through Smart Design/upgrade of Instrumentation Networks. Miguel Bagajewicz, Donald Chmielewski and Raghunathan Rengaswamy.
·         AIChE Annual Meeting. Salt Lake City, UT (2007). Optimal Instrumentation Networks for Maximum Economic Value of Plant Operations. Duyquang Nguyen and Miguel  Bagajewicz.
·         AIChE Annual Meeting. Salt Lake City, UT (2007).  Nonlinear Sensor Network Design and Upgrade for Optimal Monitoring. Miguel J. Bagajewicz and DuyQuang Nguyen.

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