Group-old

Carl Laird Group Students

Current Group Members


Transient

Sean Legg
PhD Candidate
legg.sean@gmail.com

Current strategies to place gas sensors in industrial settings are based upon heuristics or semi-quantitative approaches. Optimal sensor placement is difficult due to the large number of unknown variables that influence the risks associated with gas leaks. Heuristic and semi-quantitative approaches often yield results that are far from the optimal sensor placements in terms of cost and risk-reduction. This research focuses on the use of numerical optimization techniques to fin optimal solutions to gas sensor placement problems. Additionally, this research investigates the effects of coverage-based constraints and Conditional-Value-at-Risk constraints to the sensor placement formulation. Further work examines the variability in solutions due to the number of scenarios used for data in solving for the placement.

(show publications & presentations)

Publications
Benavides-Serrano, A., Legg, S.W., Vazquez-Roman, R., Mannan, M.S., and Laird, C.D., "A Stochastic Programming Approach for the Optimal Placement of Gas Detectors: Unavailability and Voting Strategies", to appear in Industrial & Engineering Chemistry Research, 2013. [pdf]
Legg, S.W., Wang, C., Benavides-Serrano, A.J., Laird, C.D., "Optimal Gas Detector Placement Under Uncertainty Considering Conditional-Value-At-Risk", Journal of Loss Prevention in the Process Industries, Volume 26, May 2013, Pages 410-417. [pdf]
Benavides-Serrano, A., Legg, S.W., Mannan, M.S., and Laird, C.D., "Optimizing Gas Detector Layouts by Considering False Positives and False Negatives Through Unavailability and Voting Considerations", Proceedings of, 5th Latin American Conference on Process Safety, Cartagena, Colombia, August, 2013. [pdf]
Legg, S.W., Benavides-Serrano, A.J., Siirola, J.D., Watson, J.P., Davis, S.G., Bratteteig, A., Laird, C.D., "A Stochastic Programming Approach for Gas Detector Placement Using CFD-Based Dispersion Simulations", Computers & Chemical Engineering, Volume 47, December 2012, Pages 194-201. [pdf]
Benavides-Serrano, A., Legg, S.W., Mannan, M.S., and Laird, C.D., "A stochastic programming approach for optimal gas sensor layout considering sensor reliability", Proceedings of, Mary Kay O'Connor Process Safety Center International Symposium, College Station, TX, October, 2012.
Legg, S.W., Siirola, J.D., Watson, J.P., Davis, S.G., Bratteteig, A., Laird, C.D., "A Stochastic Programming Approach for Gas Detector Placement in Process Facilities", Proceedings of, FOCAPO 2012, Savannah, GA, January, 2012.
Zhu, Y., Legg, S., and Laird, C.D., "A Multiperiod Nonlinear Programming Approach for Operation of Air Separation Plants with Variable Power Pricing", AIChE Journal, Volume 57, September 2011, Pages 2421-2430. [pdf]
Zhu, Y., Legg, S., and Laird, C.D., "Optimal Operation of Cryogenic Air Separation Systems with Demand Uncertainty and Contractual Obligations", Chemical Engineering Science, Volume 66, March 2011, Pages 953-963. [pdf]
Zhu, Y., Legg, S., and Laird, C.D., "Optimal Design of Cryogenic Air Separation Columns Under Uncertainty", Computers & Chemical Engineering, Volume 34, September 2010, Pages 1377-1384. [pdf]

Presentations
Benavides-Serrano, A., Legg, S., Mannan, M.S., and Laird, C.D., "A Quantitative Assessment on the Placement Practices of Gas Detectors in the Process Industries", submitted to Mary Kay O'Connor Process Safety Center International Symposium, College Station, TX, 2013.
Benavides-Serrano, A., Legg, S., Mannan, M.S., and Laird, C.D., "A Stochastic Programming Formulation for the Optimal Layout of Gas Detectors in the Process Industries", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Hackebeil, G., Legg, S., Laird, C.D., and Watson, J.P., "Optimal Sensor Placement With Intractably Large Scenario Spaces", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Benavides-Serrano, A., Legg, S., Mannan, M.S., and Laird, C.D., "A stochastic programming approach for optimal gas sensor layout considering sensor reliability", Mary Kay O'Connor Process Safety Center International Symposium, College Station, TX, October, 2012.
Hackebeil, G., Laird, C.D., Legg, S., and Watson, J.P., "Solution of Optimal Placement Problems in Water Networks with Intractably Large Scenario Spaces", AIChE Annual Meeting, Pittsburgh, PA, October, 2012.
Benavides-Serrano, A., Legg, S., Wang, C., and Laird, C.D., "Optimal layout of gas detector networks: A comparison study", AIChE Spring Meeting & 8th Global Congress on Process Saftey, Houston, TX, March, 2012.
Legg, S., Watson, J.P., Davis, S., and Laird, C.D., "Optimal Scenario-Based Gas Detector Placement in Process Facilities", Mary Kay O'Connor Process Safety Center International Symposium, College Station, TX, October, 2011.
Kang, J., Legg, S., Zhu, Y., and Laird, C.D., "Efficient Parallel Optimization On Emerging Computational Architectures", AIChE Annual Meeting, Salt Lake City, UT, November, 2010.
Zhu, Y., Legg, S., Kang, J., and Laird, C.D., "Parallel Solution of Nonlinear Optimization Problems on Emerging Architectures", ExxonMobil Chemical, Baytown, TX, October 19, 2010.
Legg, S. and Laird, C.D., "Parallel Nonlinear Programming Decomposition for Design Under Uncertainty Using Graphics Processing Units", Advances in Process Design II, AIChE Spring Meeting, San Antonio, TX, March 23, 2010.
Benavides-Serrano, A., Legg, S., Mannan, M.S., and Laird, C.D., "A Reliability-P-Median Formulation for optimization of Gas Detector Layout in Process Facilities", AIChE Annual Meeting, Pittsburgh, PA, October, 2012.
Legg, S., Benavides-Serrano, A., Mannan, M.S., and Laird, C.D., "Optimal Placement of Gas Detectors in Process Facilities Using Conditional-Value-At-Risk", AIChE Annual Meeting, Pittsburgh, PA, October, 2012.
Legg, S.W., Siirola, J.D., Watson, J.P., Davis, S.G., Bratteteig, A., and Laird, C.D., "A Stochastic Programming Approach for Gas Detector Placement in Process Facilities", FOCAPO 2012, Savannah, GA, January, 2012.
Zhu, Y., Word, D.P., Legg, S., Siirola, J., and Laird, C.D., "Exploiting Modern Computing Architectures for Efficient Large-Scale Nonlinear Programming", 10th International Symposium on Process Systems Engineering, PSE'09, Salvador, Brazil, August 16-20, 2009. (Won Best Poster Award)
Legg, S. and Laird, C.D., "Estimation of Seasonal Parameters and Susceptibility Numbers for Varicella-Zoster", REU Poster Presentation, Texas A&M University, College Station, TX, 2008.



Transient

Angelica (Wong) Mann
PhD Candidate
angelica.v.wong@gmail.com

This research focuses on the development of real-time algorithms for performing source inversion and response planning in the event of an accidental or intentional contamination in a water distribution system. Since these systems would work in a real-time setting, these algorithms must be able to solve efficiently and effectively for very large networks when given only limited measurement information due to limiting resources. To help meet these goals we have been developing efficient water quality models that can be used in an inversion context, as well as mixed-integer linear and quadratic programming formulations for source location identification and optimal sampling. These approaches have been shown to effectively find the source and extent of contamination given a real water network model.

(show publications & presentations)

Publications
Mann, A.V., Hackebeil, G., Laird, C.D., "Explicit Water Quality Model Generation and Rapid Multi-Scenario Simulation", Journal of Water Resources Planning and Management, August 2012.
Mann, A.V., McKenna, S.A., Hart, W.E., and Laird, C.D., "Real-Time Inversion in Large-Scale Water Networks Using Discrete Measurements", Computers & Chemical Engineering, Volume 37, February 2012, Pages 143-151. [pdf]
Hackebeil, G., Mann, A.V., and Laird, C.D., "Tailored Solver for Rapid Water Quality Simulation with Merlion", Proceedings of, WDSA, Adelaide, Australia, , 2012.
Hackebeil, G., Mann, A.V., Hart, W., Klise, K., and Laird, C.D., "A Stochastic Programming Formulation for Chlorine Booster Station Placement to Protect Large-Scale Water Distribution Systems", Proceedings of, PSE 2012, Singapore, July, 2012.
Laird, C.D., Wong, A.V., and Akesson, J., "Parallel Solution of Large-Scale Dynamic Optimization Problems", In: E.N. Pistikopoulos, M.C. Georgiadis, and A.C. Kokossis, Eds., Computer Aided Chemical Engineering, Volume 29, Elsevier, 2011, 21st European Symposium on Computer Aided Process Engineering, Pages 813-817. [pdf]
Wong, A., Young, J., McKenna, S., Hart, W., and Laird, C.D., "Optimal Determination of Grab Sample Locations and Source Inversion in Large-Scale Water Distribution Systems", Proceedings of, Water Distribution Systems Analysis, Tucson, AZ, September, 2010, Pages 412-425. (Nominated for Best Paper Award)
Wong, A., McKenna, S., Hart, W., and Laird, C.D., "Real-Time Inversion and Response Planning in Large-Scale Networks", In: S. Pierucci and G. Buzi Ferraris, Eds., Computer Aided Chemical Engineering, Volume 28, Elsevier, 2010, 20th European Symposium on Computer Aided Process Engineering, Pages 1027-1032. [pdf]

Presentations
Seth, A., Mann, A., Klise, K., Haxton, T., and Laird, C.D., "Development of a Testbed for Contaminant Source Inversion Methods", EWRI 2013, Cincinnati, OH, May, 2013.
Seth, A., Mann, A., McGee, S., and Laird, C.D., "A Real-Time Source Inversion and Optimal Sampling Strategy for Large-Scale Drinking Water Distribution Systems", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Hackebeil, G., Mann, A., and Laird, C.D., "Optimal Booster Station Placement for Protecting Water Distribution Systems", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Mann, A., Hackebeil, G., Rodriguez, J., Klise, K.A., Laird, C.D., and Haxton, T., "Optimal Design and Operation of Real-Time Response Systems for Water Security", AIChE Annual Meeting, Pittsburgh, PA, November, 2012.
Hackebeil, G., Mann, A.V., and Laird, C.D., "Tailored Solver for Rapid Water Quality Simulation with Merlion", WDSA 2012, Adelaide, Australia, September, 2012.
Hackebeil, G., Mann, A.V., Hart, W., Klise, K., and Laird, C.D., "A Stochastic Programming Formulation for Chlorine Booster Station Placement to Protect Large-Scale Water Distribution Systems", PSE 2012, Singapore, July, 2012.
Klise, K., Laird, C.D., Mann, A., Hackebeil, G., and Haxton, T., "Optimal booster station placement considering various reaction dynamics", EWRI 2012, Albuquerque, NM, May, 2012.
Mann, A.V., Hackebeil, G., and Laird, C.D., "Efficient Solution of Large-Scale Water Quality Models for Scenario Generation", EWRI 2012, Albuquerque, NM, May, 2012.
Wong, A.V., Hackebeil, G.A., Hart, W., Klise, K., and Laird, C.D., "Optimal Layout of Chlorine Booster Stations for Water Supply Network Security", INFORMS Annual Meeting, Charlotte, NC, November, 2011.
Hackebeil, G., Wong, A.V., Klise, K.A., Hart, W., and Laird, C.D., "Optimal Chlorine Booster Station Placement for Contamination Response in Water Distribution Systems Using Stochastic Programming", AIChE Annual Meeting, Minneapolis, MN, October, 2011.
Laird, C.D., Wong, A.V., and Akesson, J., "Parallel Solution of Large-Scale Dynamic Optimization Problems", ESCAPE21, Chalkidiki, Greece, June, 2011.
Wong, A.V., Hart, W., McKenna, S., and Laird, C.D., "Source Inversion and Optimal Sampling in Large-Scale Drinking Water Distribution Systems", 12th INFORMS Computing Society Conference, Monterey, CA, January, 2011.
Wong, A.V., McKenna, S., Hart, W., and Laird, C.D., "Source Inversion and Response Management in Large-Scale Water Distribution Systems", AIChE Annual Meeting, Salt Lake City, UT, November, 2010.
Wong, A., Young, J., McKenna, S., Hart, W., and Laird, C.D., "Optimal Determination of Grab Sample Locations and Source Inversion in Large-Scale Water Distribution Systems", Water Distribution Systems Analysis, Tuscon, AZ, September, 2010.
Wong, A., McKenna, S., Hart, W., and Laird, C.D., "Real-Time Inversion and Response Planning in Large-Scale Networks", ESCAPE20, Ischia, Italy, June 7, 2010.
Wong, A. and Laird, C.D., "Optimal Design of a Real-Time Monitoring System for Water Distribution Networks", Advances in Process Design I, AIChE Spring Meeting, San Antonio, TX, March 23, 2010.
Wong, A., McKenna, S., Hart, W., and Laird, C.D., "Real-Time Contaminant Detection and Inversion in Large-Scale Water Networks", 65th Annual Instrumentation Symposium for the Process Industries, College Station, TX, January 26-28, 2010.
Wong, A., McKenna, S., and Laird, C.D., "Source Location Workshop: Real-Time Numerical Inversion", PUB Singapore, Singapore, September, 2009.
Wong, A., McKenna, S., Hart, W., and Laird, C.D., "Real-Time Inversion and Response Planning in Large-Scale Networks", Process Science and Technology Center (PSTC) Fall 2009 Meeting, College Station, TX, 2009.



Transient

Daniel Word
PhD Candidate
daniel.p.word@gmail.com

Reliable, mechanistic models for the spread of infectious disease are valuable for improving our understanding of important factors affecting disease dynamics and for helping guide public health decision making. Our work has focused on developing deterministic and stochastic discrete-time and continuous time models of childhood infectious diseases. We bring large-scale nonlinear optimization expertise to provide a framework for efficient estimation of long-term dynamic models. These estimation problems are similar to classic ill-posed inverse formulations, and effective regularization is required to obtain reliable seasonal estimates. Current research includes further refinement of model structure to improve their ability to extrapolate.

(show publications & presentations)

Publications
Kang, J., Word, D.P., and Laird, C.D., "An interior-point method for efficient solution of block-structured NLP problems using an implicit Schur-complement decomposition", submitted to Computers and Chemical Engineering, 2013.
Word, D.P., Young, J.K., Cummings, D.A.T., Iamsirithaworn, S., and Laird, C.D., "Interior-Point Methods for Estimating Seasonal Parameters in Discrete-Time Infectious Disease Models", to appear in PLOS One, 2013.
Word, D.P., Kang, J., Akesson, J., and Laird, C.D., "Efficient Parallel Solution of Large-Scale Nonlinear Dynamic Optimization Problems", submitted to Computational Optimization and Applications, 2013.
Word, D.P., Cummings, D.A.T., Burke, D.S., Iamsirithaworn, S., and Laird, C.D., "A Nonlinear Programming Approach for Estimation of Transmission Parameters in Childhood Infectious Disease Using a Continuous Time Model", Journal of the Royal Society Interface, Volume 9, August 2012, Pages 1983-1997. [pdf]
Word, D.P., Watson, J.P., Woodruff, D., and Laird, C.D., "A Progressive Hedging Approach for Parameter Estimation of Stochastic Nonlinear Programs", Proceedings of, PSE 2012, Singapore, July, 2012.
Word, D.P., Abbott III, G.H., Cummings, D, and Laird, C.D., "Estimating Seasonal Drivers in Childhood Infectious Diseases with Continuous Time and Discrete-Time Models", Proceedings of, American Control Conference (ACC) 2010, Baltimore, MD, June 30 - July 2, 2010, Pages 5137-5142. [pdf] (Invited Contribution)
Word, D.P., Young, J., Cummings, D., and Laird, C.D., "Estimation of seasonal transmission parameters in childhood infectious disease using a stochastic continuous time model", In: S. Pierucci and G. Buzi Ferraris, Eds., Computer Aided Chemical Engineering, Volume 28, Elsevier, 2010, 20th European Symposium on Computer Aided Process Engineering, Pages 229-234. [pdf]
Zhu, Y., Word, D., Siirola, J., and Laird, C.D., "Exploiting Modern Computing Architectures for Efficient Large-Scale Nonlinear Programming", In: R.M. de Brito Alves, C.A.O. do Nascimento and E.C. Biscaia, Jr., Eds., Computer Aided Chemical Engineering, Volume 27, Elsevier, 2009, 10th International Symposium on Process Systems Engineering: Part A, Pages 783-788. [pdf] (Won best poster award)

Presentations
Seth, A., Word, D.P., Kang, J., Cummings, D., Laird, C.D., "NLP Approaches for Estimation of Seasonal Transmission Parameters in Childhood Infectious Diseases", INFORMS Annual Meeting, Minneapolis, MN, October 8, 2013.
Cao, Y., Word, D.P., Watson, J.P., Woodruff, D.L., Laird, C.D., "Nonlinear Parameter Estimation in Parallel Using Progressive Hedging", INFORMS Annual Meeting, Minneapolis, MN, October 6, 2013.
Cao, Y., Word, D.P., Watson, J.P., Woodruff, D.L., Laird, C.D., "Progressive Hedging for Non-Linear Models that Arise in Parameter Estimation Problems", ICSP-SPXIII 2013, Bergamo, Italy, July, 2013.
Word, D.P., Kang, J., Watson, J.P., Woodruff, D.L., Akesson, J., and Laird, C.D., "Parallel Solution of Large-Scale Nonlinear Parameter Estimation Problems", ICCOPT Portugal, July, 2013.
Kang, J., Word, D.P., Akesson, J., Laird, C.D., "Efficient Optimization of Nonlinear Dynamic Systems Under Uncertainty Using Parallel Decomposition", 10th World Congress on Structural and Multidisciplinary Optimization (WCSMO10), Orlando, FL, USA, May, 2013.
Word, D.P., Watson, J.P., Woodruff, D., and Laird, C.D., "Parallel Solution of Nonlinear Parameter Estimation Problems Using Progressive Hedging", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Word, D.P., Kang, J., Akesson, J., and Laird, C.D., "A Schur-Complement Decomposition Approach for Efficient Parallel Optimization of Dynamic Systems", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Kang, J., Word, D.P., Akesson, J., and Laird, C.D., "Parallel Decomposition of Nonlinear Dynamic Optimization Problems", AIChE Annual Meeting, Pittsburgh, PA, October, 2012.
Kang, J., Word, D.P., Woodruff, D.L., Watson, J.P., and Laird, C.D., "Parallel Solution of Structured Nonlinear Problems Using Pyomo and PySP", 21st International Symposium on Mathematical Programming (ISMP), Berlin, Germany, August, 2012.
Word, D.P., Watson, J.P., Woodruff, D., and Laird, C.D., "A Progressive Hedging Approach for Parameter Estimation of Stochastic Nonlinear Programs", PSE 2012, Singapore, July, 2012.
Word, D.P., Watson, J.P., Woodruff, D., and Laird, C.D., "Decomposition Strategies in Pyomo for Estimation of a Spatio-Temporal Infectious Disease Model", INFORMS Annual Meeting, Charlotte, NC, November, 2011.
Word, D.P., Hart, W., Laird, C.D., and Siirola, J., "Representation and Solution of Generalized Disjunctive Programming Problems Using Pyomo", 12th INFORMS Computing Society Conference, Monterey, CA, January, 2011.
Word, D.P., Hart, W., Laird, C.D., and Siirola, J., "Representation and Solution of Generalized Disjunctive Programming Problems Using Pyomo", INFORMS Annual Meeting, Austin, TX, November, 2010.
Word, D.P., Abbott III, G.H., Cummings, D, and Laird, C.D., "Estimating Seasonal Drivers in Childhood Infectious Diseases with Continuous Time and Discrete-Time Models", ACC2010, Baltimore, MD, July 2, 2010.
Word, D.P., Young, J., Cummings, D., and Laird, C.D., "Estimation of seasonal transmission parameters in childhood infectious disease using a stochastic continuous time model", ESCAPE20, Ischia, Italy, June 9, 2010.
Word, D.P., Abbott III, G.H., Young, J., Kolodziej, S., and Laird, C.D., "Improved Estimation and Control for Large-Scale Models of Infectious Disease Spread", Modeling and Control of Biomedical Systems - I, AIChE Annual Meeting, Nashville, TN, November, 2009.
Word, D.P., Watson, J.P., Woodruff, D.L., and Laird, C.D., "Parallel Decomposition Strategies for Estimation of a Spatially Distributed, Nonlinear, Childhood Infectious Disease Model", AIChE Annual Meeting, Minneapolis, MN, October 16-21, 2011.
Zhu, Y., Word, D.P., Legg, S., Siirola, J., and Laird, C.D., "Exploiting Modern Computing Architectures for Efficient Large-Scale Nonlinear Programming", 10th International Symposium on Process Systems Engineering, PSE'09, Salvador, Brazil, August 16-20, 2009. (Won Best Poster Award)



Transient

Gabe Hackebeil
Researcher
gabehack@gmail.com

Mathematical programming has proven to be an efficient tool for design, optimization, and online operation of complex engineered systems. Algebraic modeling languages provide a convenient mechanism for the user to formulate mathematical models and optimization formulations in a language that is similar to the mathematical description of the problem, including constructs for defining sets, expressions, constraints, and objectives. Pyomo is a new open-source algebraic optimization language implemented in Python. Pyomo provides general functionality to formulate and solve optimization problems with little or no programming knowledge, but also provides the flexibility to implement high-level language constructs. This work focuses on the design and implementation of high level modeling capabilities in the Pyomo framework, including customized algorithms for solving mixed-integer nonlinear programming problems (MINLPs) and extensions that supports parallel programming for solution of difficult stochastic programming problems.

(show publications & presentations)

Publications
Serpas, M., Hackebeil, G., Laird, C.D., and Hahn, J., "Sensor Location for Nonlinear Dynamic Systems via Observability Analysis and Max-Det Optimization", Computer & Chemical Engineering, Volume 48, January 2013, Pages 105-112. [pdf]
Mann, A.V., Hackebeil, G., Laird, C.D., "Explicit Water Quality Model Generation and Rapid Multi-Scenario Simulation", Journal of Water Resources Planning and Management, August 2012.
Hackebeil, G., Mann, A.V., and Laird, C.D., "Tailored Solver for Rapid Water Quality Simulation with Merlion", Proceedings of, WDSA, Adelaide, Australia, 2012.
Hackebeil, G., Mann, A.V., Hart, W., Klise, K., and Laird, C.D., "A Stochastic Programming Formulation for Chlorine Booster Station Placement to Protect Large-Scale Water Distribution Systems", Proceedings of, PSE 2012, Singapore, July, 2012.

Presentations
Klise, K., Laird, C.D., Hackebeil, G., Seth, A., Murray, R., and Haxton, T. , "Evaluation of booster station placement for water quality and water security concerns", EWRI 2013, Cincinnati, OH, May, 2013.
Hackebeil, G., Legg, S., Laird, C.D., and Watson, J.P., "Optimal Sensor Placement With Intractably Large Scenario Spaces", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Hackebeil, G., Mann, A., and Laird, C.D., "Optimal Booster Station Placement for Protecting Water Distribution Systems", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Hackebeil, G., "An Introduction to the Piecewise Modeling Component in Pyomo", Coopr Pyomo Workshop, INFORMS Computing Society, Santa Fe, NM, January, 2013.
Mann, A., Hackebeil, G., Rodriguez, J., Klise, K.A., Laird, C.D., and Haxton, T., "Optimal Design and Operation of Real-Time Response Systems for Water Security", AIChE Annual Meeting, Pittsburgh, PA, November, 2012.
Hackebeil, G., Laird, C.D., Legg, S., and Watson, J.P., "Solution of Optimal Placement Problems in Water Networks with Intractably Large Scenario Spaces", AIChE Annual Meeting, Pittsburgh, PA, October, 2012.
Hackebeil, G., Mann, A.V., and Laird, C.D., "Tailored Solver for Rapid Water Quality Simulation with Merlion", WDSA 2012, Adelaide, Australia, September, 2012.
Hackebeil, G., Mann, A.V., Hart, W., Klise, K., and Laird, C.D., "A Stochastic Programming Formulation for Chlorine Booster Station Placement to Protect Large-Scale Water Distribution Systems", PSE 2012, Singapore, July, 2012.
Klise, K., Laird, C.D., Mann, A., Hackebeil, G., and Haxton, T., "Optimal booster station placement considering various reaction dynamics", EWRI 2012, Albuquerque, NM, May, 2012.
Mann, A.V., Hackebeil, G., and Laird, C.D., "Efficient Solution of Large-Scale Water Quality Models for Scenario Generation", EWRI 2012, Albuquerque, NM, May, 2012.
Wong, A.V., Hackebeil, G.A., Hart, W., Klise, K., and Laird, C.D., "Optimal Layout of Chlorine Booster Stations for Water Supply Network Security", INFORMS Annual Meeting, Charlotte, NC, November, 2011.
Hackebeil, G., Wong, A.V., Klise, K.A., Hart, W., and Laird, C.D., "Optimal Chlorine Booster Station Placement for Contamination Response in Water Distribution Systems Using Stochastic Programming", AIChE Annual Meeting, Minneapolis, MN, October, 2011.
Hackebeil, G. and Laird, C.D., "Global Optimization for Estimation of On/Off Seasonality in Infectious Disease Spread Using Pyomo", 12th INFORMS Computing Society Conference, Monterey, CA, January, 2011.
Hackebeil, G. and Laird, C.D., "Global Optimization for Estimation of On/Off Seasonality in Infectious Disease Spread Using Pyomo", INFORMS Annual Meeting, Austin, TX, November, 2010.



Transient

Jia Kang
PhD Candidate
kangjia1127@gmail.com
Co-advised with Prof. J. Hahn

Large-scale, nonlinear dynamic models frequently arise when describing the physics of important engineering and biological problems. In this research, we are developing new algorithms that exploit concurrent computing architectures to provide efficient parallel solution of large-scale parameter estimation problems, focusing on those with both temporal and spatial structure that can be exploited.

(show publications & presentations)

Publications
Kang, J., Word, D.P., and Laird, C.D., "An interior-point method for efficient solution of block-structured NLP problems using an implicit Schur-complement decomposition", submitted to Computers and Chemical Engineering, 2013.
Word, D.P., Kang, J., Akesson, J., and Laird, C.D., "Efficient Parallel Solution of Large-Scale Nonlinear Dynamic Optimization Problems", submitted to Computation Optimization and Applications, 2013.

Presentations
Kang, J., Word, D.P., Akesson, J., and Laird, C.D., "An Efficient Parallel Algorithm for Optimal Operation Under Uncertainty", to be presented at AIChE Annual Meeting, San Francisco, CA, 2013.
Seth, A., Word, D.P., Kang, J., Cummings, D., Laird, C.D., "NLP Approaches for Estimation of Seasonal Transmission Parameters in Childhood Infectious Diseases", INFORMS Annual Meeting, Minneapolis, MN, October 8, 2013.
Word, D.P., Kang, J., Watson, J.P., Woodruff, D.L., Akesson, J., and Laird, C.D., "Parallel Solution of Large-Scale Nonlinear Parameter Estimation Problems", ICCOPT Portugal, July, 2013.
Kang, J., Word, D.P., Akesson, J., Laird, C.D., "Efficient Optimization of Nonlinear Dynamic Systems Under Uncertainty Using Parallel Decomposition", 10th World Congress on Structural and Multidisciplinary Optimization (WCSMO10), Orlando, FL, USA, May, 2013.
Kang, J., and Laird, C.D., "An Efficient Parallel Decomposion Algorithm for Block-Structured Nonlinear Programming Problems", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Word, D.P., Kang, J., Akesson, J., and Laird, C.D., "A Schur-Complement Decomposition Approach for Efficient Parallel Optimization of Dynamic Systems", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Kang, J., Watson, J.P. and Laird, C.D., "Robust Optimization for Unit Commitment using Pyomo", Coopr Workshop, INFORMS Computing Society, Santa Fe, NM, January, 2013.
Kang, J., Word, D.P., Akesson, J., and Laird, C.D., "Parallel Decomposition of Nonlinear Dynamic Optimization Problems", AIChE Annual Meeting, Pittsburgh, PA, October, 2012.
Kang, J., Word, D.P., Woodruff, D.L., Watson, J.P., and Laird, C.D., "Parallel Solution of Structured Nonlinear Problems Using Pyomo and PySP", 21st International Symposium on Mathematical Programming (ISMP), Berlin, Germany, August, 2012.
Kang, J., Akesson, J., and Laird, C.D., "Parallel Solution of Large-Scale, Block-Structured, Nonlinear Programming Problems with Significant Coupling", AIChE Annual Meeting, Minneapolis, MN, October, 2011.
Kang, J., Legg, S., Zhu, Y., and Laird, C.D., "Efficient Parallel Optimization On Emerging Computational Architectures", AIChE Annual Meeting, Salt Lake City, UT, November, 2010.
Zhu, Y., Legg, S., Kang, J., and Laird, C.D., "Parallel Solution of Nonlinear Optimization Problems on Emerging Architectures", ExxonMobil Chemical, Baytown, TX, October 19, 2010.



 
Transient

Yankai Cao
PhD Candidate
nanhaitu@tamu.edu
Co-advised with Prof. J. Hahn

Today, vaccines play an important role in human lives. To address dynamic national requirements for various pharmaceuticals, there is a need for reconfigurable therapeutics manufacturing facilities that are capable of rapid product changeover. Limitations of the existing manufacturing infrastructure are made painfully clear by recurring drug shortages. This research focuses on developing a flexible modeling and nonlinear programming framework for optimizing virus-based production of therapeutics in a reconfigurable facility.

(show publications & presentations)

Presentations
Cao, Y., Word, D.P., Watson, J.P., Woodruff, D.L., Laird, C.D., "Nonlinear Parameter Estimation in Parallel Using Progressive Hedging", INFORMS Annual Meeting, Minneapolis, MN, October 6, 2013.
Cao, Y., Word, D.P., Watson, J.P., Woodruff, D.L., Laird, C.D., "Progressive Hedging for Non-Linear Models that Arise in Parameter Estimation Problems", ICSP-SPXIII 2013, Bergamo, Italy, July, 2013.
Cao, Y., and Laird, C.D., "An Augmented Lagrangian Interior-Point Approach for Parallel Solution of Large-Scale NLP Problems on Graphics Processing Units", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Cao, Y. and Laird, C.D., "An Augmented Lagrangian Approach for Parallel Solution of NLP Problems On Graphics Processing Units", AIChE Annual Meeting, Pittsburgh, PA, October, 2012.



Transient

Arpan Seth
PhD Candidate
aseth1@tamu.edu

As the size of nonlinear optimization problems continues to increase, general purpose tools, coupled with standard desktop computing hardware, are not able to provide efficient solution. Furthermore, computer chip manufacturers are no longer focusing on increasing clock speed, but rather on hyper-threading and multicore architectures. This research focuses on the development of numerical solution strategies that can efficiently utilize emerging computing architectures like the GPU.

(show publications & presentations)

Presentations
Seth, A., McGee, S., McKenna, S., Hart, D.B., and Laird, C.D., "An application for real-time response to contamination events in a large-scale public water network", to be presented at AIChE Annual Meeting, San Francisco, CA, 2013.
Seth, A., Word, D.P., Kang, J., Cummings, D., Laird, C.D., "NLP Approaches for Estimation of Seasonal Transmission Parameters in Childhood Infectious Diseases", INFORMS Annual Meeting, Minneapolis, MN, October 8, 2013.
Klise, K., Laird, C.D., Hackebeil, G., Seth, A., Murray, R., and Haxton, T. , "Evaluation of booster station placement for water quality and water security concerns", EWRI 2013, Cincinnati, OH, May, 2013.
Seth, A., Mann, A., Klise, K., Haxton, T., and Laird, C.D., "Development of a Testbed for Contaminant Source Inversion Methods", EWRI 2013, Cincinnati, OH, May, 2013.
Seth, A., Mann, A., McGee, S., and Laird, C.D., "A Real-Time Source Inversion and Optimal Sampling Strategy for Large-Scale Drinking Water Distribution Systems", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.



Transient

Shawn McGee
Researcher
shawn98ag@yahoo.com

Concern regarding the accidental or intentional contamination in a water distribution system has led to the development of tools to perform source inversion and response planning for these systems. However, these tools are often difficult to install and then require a great deal of training to learn their proper use. To overcome these limitations, this research focuses on the development of a graphical, web-based user interface to serve as the front-end for the real-time algorithms for performing source inversion and response planning that have are being developed by other researchers.

(show publications & presentations)

Presentations
Seth, A., McGee, S., McKenna, S., Hart, D.B., and Laird, C.D., "An application for real-time response to contamination events in a large-scale public water network", submitted to AIChE Annual Meeting, San Francisco, CA, 2013.
Seth, A., Mann, A., McGee, S., and Laird, C.D., "A Real-Time Source Inversion and Optimal Sampling Strategy for Large-Scale Drinking Water Distribution Systems", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.



Transient

Alberto Jose Benavides-Serrano
PhD Candidate
albertojbs@neo.tamu.edu

Current strategies to place gas sensors in industrial settings are based upon heuristics or semi-quantitative approaches. Optimal sensor placement is difficult due to the large number of unknown variables that influence the risks associated with gas leaks. Heuristic and semi-quantitative approaches can give results that are far from optimal in terms of cost and risk reduction. This research presents adaptations to a sensor placement formulation which incorporate sensor voting schemes and probability of sensor failure. In many instances, release events are not considered detected until multiple detectors acknowledge the release. Therefore, modified formulations must be developed to take into account this need for sensor voting. Additionally, this research considers adaptations to the original sensor placement formulation that account for the imperfect sensor, or the sensor that has some probability of failure.

(show publications & presentations)

Publications
Benavides-Serrano, A., Legg, S.W., Vazquez-Roman, R., Mannan, M.S., and Laird, C.D., "A Stochastic Programming Approach for the Optimal Placement of Gas Detectors: Unavailability and Voting Strategies", to appear in Industrial & Engineering Chemistry Research, 2013. [pdf]
Benavides-Serrano, A., Mannan, M.S., and Laird, C.D., "A Quantitative Assessment on the Placement Practices of Gas Detectors in the Process Industries", to appear in Proceedings, Mary Kay O'Connor Process Safety Center International Symposium, 2013.
Legg, S.W., Wang, C., Benavides-Serrano, A.J., Laird, C.D., "Optimal Gas Detector Placement Under Uncertainty Considering Conditional-Value-At-Risk", Journal of Loss Prevention in the Process Industries, Volume 26, May 2013, Pages 410-417. [pdf]
Benavides-Serrano, A., Legg, S.W., Mannan, M.S., and Laird, C.D., "Optimizing Gas Detector Layouts by Considering False Positives and False Negatives Through Unavailability and Voting Considerations", Proceedings of, 5th Latin American Conference on Process Safety, Cartagena, Colombia, August, 2013. [pdf]
Legg, S.W., Benavides-Serrano, A.J., Siirola, J.D., Watson, J.P., Davis, S.G., Bratteteig, A., Laird, C.D., "A Stochastic Programming Approach for Gas Detector Placement Using CFD-Based Dispersion Simulations", Computers & Chemical Engineering, Volume 47, December 2012, Pages 194-201. [pdf]
Benavides-Serrano, A., Legg, S.W., Mannan, M.S., and Laird, C.D., "A stochastic programming approach for optimal gas sensor layout considering sensor reliability", Proceedings of, Mary Kay O'Connor Process Safety Center International Symposium, College Station, TX, October, 2012.

Presentations
Benavides-Serrano, A., Mannan, M.S., and Laird, C.D., "Gas Detectors Layout Optimization Considering False Positive and False Negatives: A Stochastic Programming Approach and a Quantitative Assessment of the Process Industries", to be presented at AIChE Annual Meeting, San Francisco, CA, 2013.
Benavides-Serrano, A., Legg, S., Mannan, M.S., and Laird, C.D., "A Quantitative Assessment on the Placement Practices of Gas Detectors in the Process Industries", to be presented at Mary Kay O'Connor Process Safety Center International Symposium, College Station, TX, 2013.
Benavides-Serrano, A., Mannan, M.S., and Laird, C.D, "Optimizacion del Posicionamiento de Detectores de Gas: Consideracion de Falsos Positivos y Falsos Negativos a traves de Disponibilidad y Voto", San Buenaventura University, Cartagena, Colombia, August, 2013.
Benavides-Serrano, A., Mannan, M.S., and Laird, C.D, "Optimizing gas detector layouts by considering false positive and false negatives through unavailability and voting considerations", 5th Latin American Conference on Process Safety, Cartagena, Colombia, August, 2013.
Benavides-Serrano, A., Legg, S., Mannan, M.S., and Laird, C.D., "A Stochastic Programming Formulation for the Optimal Layout of Gas Detectors in the Process Industries", 13th INFORMS Computing Society Conference, Santa Fe, NM, January, 2013.
Benavides-Serrano, A., Legg, S., Mannan, M.S., and Laird, C.D., "A stochastic programming approach for optimal gas sensor layout considering sensor reliability", Mary Kay O'Connor Process Safety Center International Symposium, College Station, TX, October, 2012.
Benavides-Serrano, A., Legg, S., Wang, C., and Laird, C.D., "Optimal layout of gas detector networks: A comparison study", AIChE Spring Meeting & 8th Global Congress on Process Saftey, Houston, TX, March, 2012.
Benavides-Serrano, A., Legg, S., Mannan, M.S., and Laird, C.D., "A Reliability-P-Median Formulation for optimization of Gas Detector Layout in Process Facilities", AIChE Annual Meeting, Pittsburgh, PA, October, 2012.
Legg, S., Benavides-Serrano, A., Mannan, M.S., and Laird, C.D., "Optimal Placement of Gas Detectors in Process Facilities Using Conditional-Value-At-Risk", AIChE Annual Meeting, Pittsburgh, PA, October, 2012.

Transient

Xiaorui YU
M.S. Student
yxr6648787@gmail.com

System in chemical, petrochemical onshore, and offshore facilities are usually very complicated, and include many subsystems with many safety issue scenarios. Inspection and maintenance play a very important role in keeping plants and onshore and offshore facilities safe. Determining optimal maintenance interval is difficult due to the complicated structure of these systems and the large number of unknown variables that influence the risks associated with the many failure scenarios. This research combines both Quantitative Risk Assessment (QRA) methods and optimization techniques to build an optimization model and find optimal solution for maintenance interval scheduling.


 

Former Group Members


Transient

Chen Wang
Post Doctorate

 
Transient

Yu Zhu
PhD 

Transient

Ahmed Rabie
Master's Student

 
Transient

George Abbot III
Master's Student

Transient

Derrick Thomas
Master's Student
Co-advised with Prof. S. Mannan

 

Undergraduate Group Members


Jeremiah Harris, Chemical Engineering Student (Fall 2012 -- Present)
Michael Bynum, Chemical Engineering Student (Fall 2012 -- Present)
Logan Barnes, Chemical Engineering Student (Summer 2012 -- Present)
Joshua Lucas, Chemical Engineering Student (Summer 2012)
Jose Santiago Rodriguez, Colombian Exchange Student (Spring 2012 -- Fall 2012)
Anke Iglesias, Chemical Engineering Student (REU Summer 2010)
Tylan Higley, Chemical Engineering Student (Summer 2010)
Ali El-Halwagi, Chemical Engineering Student (Summer 2010 -- Summer 2012)
Kristen Young, Chemical Engineering Student (Spring 2010)
Gabriel Hackebeil, Chemical Engineering Student (Fall 2009 -- Present)
Brandon Barrera, Chemical Engineering Student (REU Student Summer 2009, Fall 2009, Spring 2010)
Scott Kolodziej, Chemical Engineering Student (Spring 2009, USRG Student Summer 2009)
Amy Lindsey, Chemical Engineering Student (Spring 2009)
Shawn Bernardy, Chemical Engineering Student (Spring 2009)
Chris Fain, Chemical Engineering Student (Fall 2008)
German Oliveros, Colombian Exchange Student (Spring 2008 -- Fall 2008)
Derrick Thomas, Chemical Engineering Student (USRG Summer 2008, Fall 2008)
Sean Legg, Chemical Engineering Student (REU Summer 2008)
Ethan Demeter, Chemical Engineering Student (Spring 2008, USRG Summer 2008)
James Young, Industrial Engineering Student (Spring 2008 -- Summer 2010)