Vassilios Tzouanas | University of Houston-Downtown (original) (raw)

Papers by Vassilios Tzouanas

Research paper thumbnail of Practical Design of PID-type Controllers with Constraints

He also serves as assistant department chairman. He received all his degrees in chemical engineer... more He also serves as assistant department chairman. He received all his degrees in chemical engineering and obtained his Ph.D. from Lehigh University. His area of specialization is process modeling, simulation and control. He has worked in the industry for 19 years where he held technical and management positions with major operating companies as well as process control technology development companies. Since 2010, he has been with UHD where he teaches university courses in process control, modeling and simulation, process design and operation, applied thermodynamics and heat transfer, and numerical methods. Dr. Tzouanas' research interests include process modeling, simulation and design, process control, and renewable energy systems. Dr. Tzouanas is an ABET Program Evaluator (PEV) for Engineering and Engineering Technology programs. He is also member of AIChE and ASEE.

Research paper thumbnail of Design of Adaptive PID Controllers Subject to Process Constraints

Design of Adaptive PID Controllers Subject to Process Constraints

2023 9th International Conference on Control, Decision and Information Technologies (CoDIT)

Research paper thumbnail of A Transmission Rate Estimator & Controller for Infectious Disease SIR Models - Constant Case

A Transmission Rate Estimator & Controller for Infectious Disease SIR Models - Constant Case

2023 American Control Conference (ACC)

Research paper thumbnail of Data Science and Traditional Engineering and Technology Programs—How to Improve Operational Excellence

2020 CIEC Proceedings

This paper focuses on the application of Data Science to improving operational excellence (OE) fo... more This paper focuses on the application of Data Science to improving operational excellence (OE) for the process industries. By operational excellence, we mean the ability of a processing facility to operate safely, reliably and in an environmentally friendly manner while producing quality products, minimizing operating costs, and adapting to changing market conditions. Improving OE requires collaboration among professionals from different technical backgrounds. In addition, it involves the analysis of large amounts of data to help make intelligent business decisions. Recent advances in data science, big data analytics, and machine learning could help in that regard. For instance, such techniques can help improve process safety, predict equipment failure, provide better data visualization, manage alarms and abnormal operating conditions, develop inferential models, improve performance of automation strategies and real-time optimization, and help make decisions in planning long term operations. The paper provides an overview of various techniques that have been used in the process industries to improve OE and suggests curricular enhancements to traditional engineering and technology programs to educate engineers in data science, big data analytics, and machine learning.

Research paper thumbnail of Classical soil gardens versus outdoor hydroponic gardens utilizing energy and water capture technologies to combat climate change

Classical soil gardens versus outdoor hydroponic gardens utilizing energy and water capture technologies to combat climate change

Journal of Emergency Management, 2021

Many outdoor gardens are designed for plants to grow in soil. Few gardens are designed for plants... more Many outdoor gardens are designed for plants to grow in soil. Few gardens are designed for plants to be hydroponically grown outside with energy and water capture technologies. The feasibility of a self-sufficient, adaptive hydroponic garden harnessing energy from multiple renewable energy (solar and wind) and rainwater collection techniques while producing food has been considered. This study’s primary objective is to conduct a comparative analysis between a traditional soil garden bed and an outdoor hydroponic system, called Pangea. The study findings suggest no significant statistical difference between the plants grown in traditional soil and a Pangea system. Additional objectives of this study include a comparative analysis of water and energy differentials between a standard garden and Pangea. This study’s energy findings suggest that the Pangea system produces 0.05 kWh of energy to 0 kWh of energy production in the classic soil over a month timespan. The water production find...

Research paper thumbnail of Theory and experimental evaluation of adaptive control and identification methods

Theory and experimental evaluation of adaptive control and identification methods

Research paper thumbnail of Modeling , Simulation and Control of Temperature and Level in a Multivariable Water Tank Process *

The project is concerned with the design of a water tank process and experimental evaluation of f... more The project is concerned with the design of a water tank process and experimental evaluation of feedback control structures to achieve water level and temperature control at desired set point values. The manipulated variables are the pump power, on the water outflow line, and heat supply to the tank. Detailed, first principles-based, dynamic models as well as empirical models for this interactive and multivariable process have been developed and used for controller design. Furthermore, this experimental study entails and discusses the design of the water tank process and associated instrumentation, real time data acquisition and control using the DeltaV distributed control system (DCS), process modeling, controller design, and evaluation of the performance of tuning methodologies in a closed loop manner.

Research paper thumbnail of Constrained PID design & implementation: A co-simulation framework

Constrained PID design & implementation: A co-simulation framework

2017 IEEE Conference on Control Technology and Applications (CCTA), 2017

A simulation environment is presented for tuning proportional-integral-derivative (PID) controlle... more A simulation environment is presented for tuning proportional-integral-derivative (PID) controllers that optimizes a performance criterion subject to various constraints. The tuning environment is cast under a simulation-based control design or co-simulation framework not requiring elaborate analytical optimization techniques or computing platforms; it is applicable to open loop stable or unstable processes; it is independent of the PID controller type; it accommodates controllers with proportional and/or derivative action on the error or process variable; and can be applied to the simultaneous tuning of PID controllers in a series or parallel cascade structure. The method can also account for robustness in response to modeling errors by including magnitude constraints on the nominal sensitivity function. Performance is demonstrated in simulation using Microsoft Excel and its Solver function in a Plug-and-Play approach. A PID design is applied to a two-tank level laboratory system t...

Research paper thumbnail of Urban Agricultural and Sustainability Program at Houston’s Downtown University: Combining New Curriculum, Hands-on Projects, and a Hurricane

Journal of Agriculture, Food Systems, and Community Development, 2017

The University of Houston-Downtown (UHD), a Hispanic-serving institution, launched an educational... more The University of Houston-Downtown (UHD), a Hispanic-serving institution, launched an educational program in 2016 that engages undergraduates in a summer curriculum with a hands-on project focused on urban agriculture and sustainability. The goals are to deliver new content, create purposeful interdisciplinary teams, and engage the participants, who are largely students of color, through mentoring and professional-development activities. In this reflective essay, we discuss improvements made between the first and second year and program elements that were most effective. The 2017 cohort was simultaneously engaged in two courses and the creation of an aquaponics system. Each student group created a system that could grow fish and hydroponic plants using solar energy. Qualitative student survey results indicate that the program increased student knowledge and affected career directions. The program was designed to extend mentoring from the summer through fall to optimize projects and prepare students for presentations on and offcampus. However, these plans had to be modified as Harvey, the most damaging hurricane in U.S. history, flooded the school and destroyed the student aquaponic systems. Fall plans now include rebuilding a single aquaponics system and consideration of resiliency in future sustainability initiatives. The most critical elements of this

Research paper thumbnail of Solar Powered Aquaponics: Modeling Real World Solutions through Engineering Technology

2019 ASEE Annual Conference & Exposition Proceedings

Glen was heavily involved in the Center for Urban Agriculture and Sustainability at the Universit... more Glen was heavily involved in the Center for Urban Agriculture and Sustainability at the University, participating in multiple research projects that emphasized sustainable technologies in the urban setting.

Research paper thumbnail of M.S. in Engineering Technology: Examples from Control Systems

2012 ASEE Annual Conference & Exposition Proceedings

, Downtown. His research interests focus on process control systems, process modeling, and simula... more , Downtown. His research interests focus on process control systems, process modeling, and simulation. His industrial professional experience includes management and technical positions. He is a member of AIChE.

Research paper thumbnail of Modeling and Control of Heat Integrated Distillation Columns: A Case Study

2012 ASEE Annual Conference & Exposition Proceedings

, Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, a master... more , Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, a master's of science degree in chemical engineering/process control from the University of Alberta, and a doctorate of philosophy degree in chemical engineering/process control from Lehigh University. His research interests focus on process control systems, process modeling, and simulation. His industrial professional experience includes management and technical positions. He is a member of AIChE.

Research paper thumbnail of Study of a Photo-voltaic (PV) System Using Excel: Economic Analysis, Modeling, Simulation, and Optimization

2012 ASEE Annual Conference & Exposition Proceedings

, Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, the mast... more , Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, the master's of science degree in chemical engineering/process control from the University of Alberta, and the doctorate of philosophy degree in chemical engineering/process control from Lehigh University. His research interests focus on process control systems, process modeling, and simulation. His industrial professional experience includes management and technical positions. He is a member of AIChE.

Research paper thumbnail of Design and Control of an Air Heater Process

2012 ASEE Annual Conference & Exposition Proceedings

Research paper thumbnail of Design and Control of a Twin Tank Water Process

2012 ASEE Annual Conference & Exposition Proceedings

, Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, a master... more , Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, a master's of science degree in chemical engineering/process control from the University of Alberta, and a doctorate of philosophy degree in chemical engineering/process control from Lehigh University. His research interests focus on process control systems, process modeling, and simulation. His industrial professional experience includes management and technical positions. He is a member of AIChE.

Research paper thumbnail of Design and Automation of a Zero-Energy Model House (ZEH)

2014 ASEE Annual Conference & Exposition Proceedings

Vong Hem is currently an Applications Engineer at Lectrus Corporation an electrical manufacturing... more Vong Hem is currently an Applications Engineer at Lectrus Corporation an electrical manufacturing company. His roles include developing electrical solutions for MV/LV electrical equipment and account management. He earned his BS degree in Engineering Technology from the University of Houston-Downtown.

Research paper thumbnail of Temperature and Level Control of a Multivariable Water Tank Process

2013 ASEE Annual Conference & Exposition Proceedings

Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, ... more Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, and the Doctor of Philosophy degree in Chemical Engineering/Process Control from Lehigh University. His research interests focus on process control systems, process modeling and simulation. His professional experience includes management and technical positions with chemicals, refining, and consulting companies. He is a member of AIChE and ASEE.

Research paper thumbnail of The Teamwork Conundrum: What Should be Taught and How Can We Assess Team Learning in Engineering Technology

2011 ASEE Annual Conference & Exposition Proceedings

Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, ... more Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, and the Doctor of Philosophy degree in Chemical Engineering/Process Control from Lehigh University. His research interests focus on process control systems, process modeling and simulation, artificial intelligence and expert systems. His professional experience includes management and technical positions with chemicals, refining, and consulting companies. He has published and presented a number of papers on advanced process control, real-time optimization systems, adaptive control, artificial intelligence and expert systems. He is a member of AIChE.

Research paper thumbnail of A Course on Process Design and Operation in an Engineering Technology Program

2011 ASEE Annual Conference & Exposition Proceedings

Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, ... more Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, and the Doctor of Philosophy degree in Chemical Engineering/Process Control from Lehigh University. His research interests focus on process control systems, process modeling and simulation, artificial intelligence and expert systems. His professional experience includes management and technical positions with chemicals, refining, and consulting companies. He has published and presented a number of papers on advanced process control, real-time optimization systems, adaptive control, artificial intelligence and expert systems. He is a member of AIChE.

Research paper thumbnail of Sustainable Development and Engineering Technology

2017 ASEE Annual Conference & Exposition Proceedings

In 2009 he joined the Houston Fire Department as a firefighter and is currently an active firefig... more In 2009 he joined the Houston Fire Department as a firefighter and is currently an active firefighter. He was an engineering tutor with a focus on Introduction to Circuits, Electronic Devices, and PC Applications in Engineering. He was a member of the Scholars Academy, an honors program for high achieving students. He has been a member of the International Society of Automation since 2012.

Research paper thumbnail of Practical Design of PID-type Controllers with Constraints

He also serves as assistant department chairman. He received all his degrees in chemical engineer... more He also serves as assistant department chairman. He received all his degrees in chemical engineering and obtained his Ph.D. from Lehigh University. His area of specialization is process modeling, simulation and control. He has worked in the industry for 19 years where he held technical and management positions with major operating companies as well as process control technology development companies. Since 2010, he has been with UHD where he teaches university courses in process control, modeling and simulation, process design and operation, applied thermodynamics and heat transfer, and numerical methods. Dr. Tzouanas' research interests include process modeling, simulation and design, process control, and renewable energy systems. Dr. Tzouanas is an ABET Program Evaluator (PEV) for Engineering and Engineering Technology programs. He is also member of AIChE and ASEE.

Research paper thumbnail of Design of Adaptive PID Controllers Subject to Process Constraints

Design of Adaptive PID Controllers Subject to Process Constraints

2023 9th International Conference on Control, Decision and Information Technologies (CoDIT)

Research paper thumbnail of A Transmission Rate Estimator & Controller for Infectious Disease SIR Models - Constant Case

A Transmission Rate Estimator & Controller for Infectious Disease SIR Models - Constant Case

2023 American Control Conference (ACC)

Research paper thumbnail of Data Science and Traditional Engineering and Technology Programs—How to Improve Operational Excellence

2020 CIEC Proceedings

This paper focuses on the application of Data Science to improving operational excellence (OE) fo... more This paper focuses on the application of Data Science to improving operational excellence (OE) for the process industries. By operational excellence, we mean the ability of a processing facility to operate safely, reliably and in an environmentally friendly manner while producing quality products, minimizing operating costs, and adapting to changing market conditions. Improving OE requires collaboration among professionals from different technical backgrounds. In addition, it involves the analysis of large amounts of data to help make intelligent business decisions. Recent advances in data science, big data analytics, and machine learning could help in that regard. For instance, such techniques can help improve process safety, predict equipment failure, provide better data visualization, manage alarms and abnormal operating conditions, develop inferential models, improve performance of automation strategies and real-time optimization, and help make decisions in planning long term operations. The paper provides an overview of various techniques that have been used in the process industries to improve OE and suggests curricular enhancements to traditional engineering and technology programs to educate engineers in data science, big data analytics, and machine learning.

Research paper thumbnail of Classical soil gardens versus outdoor hydroponic gardens utilizing energy and water capture technologies to combat climate change

Classical soil gardens versus outdoor hydroponic gardens utilizing energy and water capture technologies to combat climate change

Journal of Emergency Management, 2021

Many outdoor gardens are designed for plants to grow in soil. Few gardens are designed for plants... more Many outdoor gardens are designed for plants to grow in soil. Few gardens are designed for plants to be hydroponically grown outside with energy and water capture technologies. The feasibility of a self-sufficient, adaptive hydroponic garden harnessing energy from multiple renewable energy (solar and wind) and rainwater collection techniques while producing food has been considered. This study’s primary objective is to conduct a comparative analysis between a traditional soil garden bed and an outdoor hydroponic system, called Pangea. The study findings suggest no significant statistical difference between the plants grown in traditional soil and a Pangea system. Additional objectives of this study include a comparative analysis of water and energy differentials between a standard garden and Pangea. This study’s energy findings suggest that the Pangea system produces 0.05 kWh of energy to 0 kWh of energy production in the classic soil over a month timespan. The water production find...

Research paper thumbnail of Theory and experimental evaluation of adaptive control and identification methods

Theory and experimental evaluation of adaptive control and identification methods

Research paper thumbnail of Modeling , Simulation and Control of Temperature and Level in a Multivariable Water Tank Process *

The project is concerned with the design of a water tank process and experimental evaluation of f... more The project is concerned with the design of a water tank process and experimental evaluation of feedback control structures to achieve water level and temperature control at desired set point values. The manipulated variables are the pump power, on the water outflow line, and heat supply to the tank. Detailed, first principles-based, dynamic models as well as empirical models for this interactive and multivariable process have been developed and used for controller design. Furthermore, this experimental study entails and discusses the design of the water tank process and associated instrumentation, real time data acquisition and control using the DeltaV distributed control system (DCS), process modeling, controller design, and evaluation of the performance of tuning methodologies in a closed loop manner.

Research paper thumbnail of Constrained PID design & implementation: A co-simulation framework

Constrained PID design & implementation: A co-simulation framework

2017 IEEE Conference on Control Technology and Applications (CCTA), 2017

A simulation environment is presented for tuning proportional-integral-derivative (PID) controlle... more A simulation environment is presented for tuning proportional-integral-derivative (PID) controllers that optimizes a performance criterion subject to various constraints. The tuning environment is cast under a simulation-based control design or co-simulation framework not requiring elaborate analytical optimization techniques or computing platforms; it is applicable to open loop stable or unstable processes; it is independent of the PID controller type; it accommodates controllers with proportional and/or derivative action on the error or process variable; and can be applied to the simultaneous tuning of PID controllers in a series or parallel cascade structure. The method can also account for robustness in response to modeling errors by including magnitude constraints on the nominal sensitivity function. Performance is demonstrated in simulation using Microsoft Excel and its Solver function in a Plug-and-Play approach. A PID design is applied to a two-tank level laboratory system t...

Research paper thumbnail of Urban Agricultural and Sustainability Program at Houston’s Downtown University: Combining New Curriculum, Hands-on Projects, and a Hurricane

Journal of Agriculture, Food Systems, and Community Development, 2017

The University of Houston-Downtown (UHD), a Hispanic-serving institution, launched an educational... more The University of Houston-Downtown (UHD), a Hispanic-serving institution, launched an educational program in 2016 that engages undergraduates in a summer curriculum with a hands-on project focused on urban agriculture and sustainability. The goals are to deliver new content, create purposeful interdisciplinary teams, and engage the participants, who are largely students of color, through mentoring and professional-development activities. In this reflective essay, we discuss improvements made between the first and second year and program elements that were most effective. The 2017 cohort was simultaneously engaged in two courses and the creation of an aquaponics system. Each student group created a system that could grow fish and hydroponic plants using solar energy. Qualitative student survey results indicate that the program increased student knowledge and affected career directions. The program was designed to extend mentoring from the summer through fall to optimize projects and prepare students for presentations on and offcampus. However, these plans had to be modified as Harvey, the most damaging hurricane in U.S. history, flooded the school and destroyed the student aquaponic systems. Fall plans now include rebuilding a single aquaponics system and consideration of resiliency in future sustainability initiatives. The most critical elements of this

Research paper thumbnail of Solar Powered Aquaponics: Modeling Real World Solutions through Engineering Technology

2019 ASEE Annual Conference & Exposition Proceedings

Glen was heavily involved in the Center for Urban Agriculture and Sustainability at the Universit... more Glen was heavily involved in the Center for Urban Agriculture and Sustainability at the University, participating in multiple research projects that emphasized sustainable technologies in the urban setting.

Research paper thumbnail of M.S. in Engineering Technology: Examples from Control Systems

2012 ASEE Annual Conference & Exposition Proceedings

, Downtown. His research interests focus on process control systems, process modeling, and simula... more , Downtown. His research interests focus on process control systems, process modeling, and simulation. His industrial professional experience includes management and technical positions. He is a member of AIChE.

Research paper thumbnail of Modeling and Control of Heat Integrated Distillation Columns: A Case Study

2012 ASEE Annual Conference & Exposition Proceedings

, Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, a master... more , Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, a master's of science degree in chemical engineering/process control from the University of Alberta, and a doctorate of philosophy degree in chemical engineering/process control from Lehigh University. His research interests focus on process control systems, process modeling, and simulation. His industrial professional experience includes management and technical positions. He is a member of AIChE.

Research paper thumbnail of Study of a Photo-voltaic (PV) System Using Excel: Economic Analysis, Modeling, Simulation, and Optimization

2012 ASEE Annual Conference & Exposition Proceedings

, Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, the mast... more , Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, the master's of science degree in chemical engineering/process control from the University of Alberta, and the doctorate of philosophy degree in chemical engineering/process control from Lehigh University. His research interests focus on process control systems, process modeling, and simulation. His industrial professional experience includes management and technical positions. He is a member of AIChE.

Research paper thumbnail of Design and Control of an Air Heater Process

2012 ASEE Annual Conference & Exposition Proceedings

Research paper thumbnail of Design and Control of a Twin Tank Water Process

2012 ASEE Annual Conference & Exposition Proceedings

, Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, a master... more , Downtown. Tzouanas earned a diploma in chemical engineering from Aristotle University, a master's of science degree in chemical engineering/process control from the University of Alberta, and a doctorate of philosophy degree in chemical engineering/process control from Lehigh University. His research interests focus on process control systems, process modeling, and simulation. His industrial professional experience includes management and technical positions. He is a member of AIChE.

Research paper thumbnail of Design and Automation of a Zero-Energy Model House (ZEH)

2014 ASEE Annual Conference & Exposition Proceedings

Vong Hem is currently an Applications Engineer at Lectrus Corporation an electrical manufacturing... more Vong Hem is currently an Applications Engineer at Lectrus Corporation an electrical manufacturing company. His roles include developing electrical solutions for MV/LV electrical equipment and account management. He earned his BS degree in Engineering Technology from the University of Houston-Downtown.

Research paper thumbnail of Temperature and Level Control of a Multivariable Water Tank Process

2013 ASEE Annual Conference & Exposition Proceedings

Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, ... more Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, and the Doctor of Philosophy degree in Chemical Engineering/Process Control from Lehigh University. His research interests focus on process control systems, process modeling and simulation. His professional experience includes management and technical positions with chemicals, refining, and consulting companies. He is a member of AIChE and ASEE.

Research paper thumbnail of The Teamwork Conundrum: What Should be Taught and How Can We Assess Team Learning in Engineering Technology

2011 ASEE Annual Conference & Exposition Proceedings

Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, ... more Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, and the Doctor of Philosophy degree in Chemical Engineering/Process Control from Lehigh University. His research interests focus on process control systems, process modeling and simulation, artificial intelligence and expert systems. His professional experience includes management and technical positions with chemicals, refining, and consulting companies. He has published and presented a number of papers on advanced process control, real-time optimization systems, adaptive control, artificial intelligence and expert systems. He is a member of AIChE.

Research paper thumbnail of A Course on Process Design and Operation in an Engineering Technology Program

2011 ASEE Annual Conference & Exposition Proceedings

Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, ... more Master of Science degree in Chemical Engineering/Process Control from the University of Alberta, and the Doctor of Philosophy degree in Chemical Engineering/Process Control from Lehigh University. His research interests focus on process control systems, process modeling and simulation, artificial intelligence and expert systems. His professional experience includes management and technical positions with chemicals, refining, and consulting companies. He has published and presented a number of papers on advanced process control, real-time optimization systems, adaptive control, artificial intelligence and expert systems. He is a member of AIChE.

Research paper thumbnail of Sustainable Development and Engineering Technology

2017 ASEE Annual Conference & Exposition Proceedings

In 2009 he joined the Houston Fire Department as a firefighter and is currently an active firefig... more In 2009 he joined the Houston Fire Department as a firefighter and is currently an active firefighter. He was an engineering tutor with a focus on Introduction to Circuits, Electronic Devices, and PC Applications in Engineering. He was a member of the Scholars Academy, an honors program for high achieving students. He has been a member of the International Society of Automation since 2012.