- Date & Time: Tuesday, September 19, 2023; 1:00 PM
Speaker: Faruque Hasan, Texas A&M University
MERL Host: Scott A. Bortoff
Research Areas: Applied Physics, Machine Learning, Multi-Physical Modeling, Optimization
Abstract 
Carbon capture, utilization, and storage (CCUS) is a promising pathway to decarbonize fossil-based power and industrial sectors and is a bridging technology for a sustainable transition to a net-zero emission energy future. This talk aims to provide an overview of design and optimization of CCUS systems. I will also attempt to give a brief perspective on emerging interests in process systems engineering research (e.g., systems integration, multiscale modeling, strategic planning, and optimization under uncertainty). The purpose is not to cover all aspects of PSE research for CCUS but rather to foster discussion by presenting some plausible future directions and ideas.
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- Date: July 9, 2023 - July 14, 2023
MERL Contacts: Scott A. Bortoff; Ankush Chakrabarty; Stefano Di Cairano; Christopher R. Laughman; Diego Romeres; Abraham P. Vinod
Research Areas: Control, Dynamical Systems, Machine Learning, Multi-Physical Modeling, Optimization, Robotics
Brief - MERL researchers presented 9 papers and organized 2 invited/workshop sessions at the 2023 IFAC World Congress held in Yokohama, JP.
MERL's contributions covered topics including decision-making for autonomous vehicles, statistical and learning-based estimation for GNSS and energy systems, impedance control for delta robots, learning for system identification of rigid body dynamics and time-varying systems, and meta-learning for deep state-space modeling using data from similar systems. The invited session (MERL co-organizer: Ankush Chakrabarty) was on the topic of “Estimation and observer design: theory and applications” and the workshop (MERL co-organizer: Karl Berntorp) was on “Gaussian Process Learning for Systems and Control”.
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- Date & Time: Tuesday, December 20, 2022; 1:00 PM
Speaker: William M. Sisson, WBCSD North America
MERL Host: Scott A. Bortoff Abstract 
Sustainability today encompasses three interconnected imperatives that all businesses must face and help to address: the increasing impact of climate change, the degradation of natural systems, and the growth of inequality. Business leaders today are increasingly understanding, particularly with the engagement of capital markets, that investors, consumers, and other business stakeholders are setting expectations on how companies are responding to these challenges and preparing for their business impact. More and more companies have shifted from sustainability as a single function in the company to one the is integrated across the firm. This translates directly into how companies are rethinking their product design and innovation efforts for sustainability and the technologies they will require. Some product categories, like heating and air conditioning systems for buildings, are both a part of the problem as well as potentially offering real solutions.
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- Date: October 26, 2022 - October 28, 2022
Where: American Modelica Conference 2022
MERL Contacts: Scott A. Bortoff; Christopher R. Laughman
Research Area: Multi-Physical Modeling
Brief - MERL researchers provided some key contributions to the 2022 American Modelica Conference, held October 26-28 at the University of Texas, Dallas. Chris Laughman, Senior Team Leader, Multiphysical Systems, was the Executive Coordinator of the conference, and worked to plan and stage the event. Scott A. Bortoff, Chief Scientist, gave a keynote address entitled "Sustainable HVAC: Research Opportunities for Modelicans." The talk posed the question: What are the modeling and control research challenges that, if addressed, will drive meaningful innovation in sustainable building HVAC systems in the next 20 years? In addition, the paper "Performance Enhancements for Zero-Flow Simulation of Vapor Compression Cycles," by Principal Research Scientist Hongtao Qiao and Chris Laughman, was a finalist for the conference Best Paper Award.
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- Date: June 8, 2022 - June 10, 2022
Where: Atlanta, GA
MERL Contacts: Scott A. Bortoff; Ankush Chakrabarty; Stefano Di Cairano; Christopher R. Laughman; Abraham P. Vinod; Avishai Weiss
Research Areas: Control, Machine Learning, Optimization
Brief - At the American Control Conference in Atlanta, GA, MERL presented 9 papers on subjects including autonomous-vehicle decision making and motion planning, realtime Bayesian inference and learning, reference governors for hybrid systems, Bayesian optimization, and nonlinear control.
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- Date & Time: Tuesday, April 5, 2022; 11:00 AM EDT
Speaker: Albert Benveniste, Benoît Caillaud, and Mathias Malandain, Inria
MERL Host: Scott A. Bortoff
Research Areas: Dynamical Systems, Multi-Physical Modeling
Abstract 
Since its 3.3 release, Modelica offers the possibility to specify models of dynamical systems with multiple modes having different DAE-based dynamics. However, the handling of such models by the current Modelica tools is not satisfactory, with mathematically sound models yielding exceptions at runtime. In our introduction, will briefly explain why and when the approximate structural analysis implemented in current Modelica tools leads to such errors. Then we will present our multimode Pryce Sigma-method for index reduction, in which the mode-dependent Sigma-matrix is represented in a dual form, by attaching, to every valuation of the sigma_ij entry of the Sigma matrix, the predicate characterizing the set of modes in which sigma_ij takes this value. We will illustrate this multimode analysis on example, by using our IsamDAE tool. In a second part, we will complement this multimode DAE structural analysis by a new structural analysis of mode changes (and, more generally, transient modes holding for zero time). Also, mode changes often give raise to impulsive behaviors: we will present a compile-time analysis identifying such behaviors. Our structural analysis of mode changes deeply relies on nonstandard analysis, which is a mathematical framework in which infinitesimals and infinities are first class citizens.
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- Date: December 11, 2019 - December 13, 2019
Where: Nice, France
MERL Contacts: Scott A. Bortoff; Ankush Chakrabarty; Stefano Di Cairano
Research Areas: Control, Machine Learning, Optimization
Brief - At the Conference on Decision and Control, MERL presented 8 papers on subjects including estimation for thermal-fluid models and transportation networks, analysis of HVAC systems, extremum seeking for multi-agent systems, reinforcement learning for vehicle platoons, and learning with applications to autonomous vehicles.
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- Date: September 25, 2019
Where: Rensselaer Polytechnic Institute (RPI), Troy, NY
MERL Contact: Scott A. Bortoff
Research Areas: Control, Multi-Physical Modeling
Brief - The seminar, entitled “HVAC System Control and Optimization,” was part of the Mercer Distinguished Lecture Series in the Electrical, Computer and Systems Engineering Department at Rensselaer Polytechnic Institute (RPI), Troy, NY. Given on Wednesday September 25, 2019, it focused on the systems engineering and control issues associated with highly integrated Heating, Ventilation and Air Conditioning Systems for low and zero energy buildings.
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- Date: June 25, 2019 - June 28, 2019
Where: Naples, Italy
MERL Contacts: Scott A. Bortoff; Ankush Chakrabarty; Stefano Di Cairano; Devesh K. Jha; Christopher R. Laughman; Daniel N. Nikovski; Diego Romeres; William S. Yerazunis
Research Areas: Control, Machine Learning, Optimization
Brief - The European Control Conference is the premier control conference in Europe. This year MERL was well represented with papers on control for HVAC, machine learning for estimation and control, robot assembly, and optimization methods for control.
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- Date: February 12, 2019
Where: Michigan State University
MERL Contacts: Scott A. Bortoff; Stefano Di Cairano; Abraham Goldsmith
Research Areas: Control, Dynamical Systems
Brief - Uros Kalabic, of MERL's Control and Dynamical Systems group, gave a talk at the Michigan State University Mechanical Engineering Seminar. The talk, entitled "Reference governors: Industrial applications and theoretical advances," covered some of the exciting research being done at MERL on reference governors and briefly described MERL's other research areas. The abstract of the talk can be found via the link below.
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- Date: February 1, 2018
MERL Contact: Scott A. Bortoff
Research Area: Control
Brief - Scott A. Bortoff has been selected by the IEEE Control System Society Board of Governors to serve as an Associate Editor of the IEEE Control Systems Magazine, effective January 1, 2018.
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- Date: July 6, 2016 - July 8, 2016
Where: American Control Conference (ACC)
MERL Contacts: Scott A. Bortoff; Petros T. Boufounos; Stefano Di Cairano; Abraham Goldsmith; Christopher R. Laughman; Daniel N. Nikovski; Arvind Raghunathan; Yebin Wang; Avishai Weiss
Research Areas: Control, Dynamical Systems, Machine Learning
Brief - The premier American Control Conference (ACC) takes place in Boston July 6-8. This year MERL researchers will present a record 20 papers(!) at ACC, with several contributions, especially in autonomous vehicle path planning and in Model Predictive Control (MPC) theory and applications, including manufacturing machines, electric motors, satellite station keeping, and HVAC. Other important themes developed in MERL's presentations concern adaptation, learning, and optimization in control systems.
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- Date: November 11, 2015 - November 12, 2015
Where: University of Connecticut
MERL Contacts: Christopher R. Laughman; Scott A. Bortoff; Hongtao Qiao
Research Area: Data Analytics
Brief - MERL Researchers Scott A. Bortoff, Chris Laughman and Hongtao Qiao attended the North America Modelica User's Group Meeting, hosted by the University of Connecticut, November 11-12, 2015. Scott Bortoff gave the Keynote Address entitled "Using Modelica in Industrial Research and Development," and Chris Laughman and Hongtao Qiao each presented a paper on modelling of HVAC systems. The Meeting attracted approximately 80 Modelica users from a diverse set of companies and universities including United Technologies, Johnson Controls and Ford. Use of Modelica is accelerating in North America, lead by largely by automotive and similar "systems manufacturing" type companies.
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- Date: September 21, 2015
MERL Contacts: Scott A. Bortoff; Christopher R. Laughman Brief - MERL researchers Scott Bortoff, Dan Burns and Chris Laughman attended the 11th Annual Modelica Conference in Versailles, France. Modelica is a computer language for modelling and simulation of multiphysical systems. There were 421 attendees, with representatives from Toyota, automobile companies, European universities and companies like Dassault. Conference topics included a plenary on cyber-physical systems modelling by Prof. Sangiovanni Vincentelli of UC Berkeley, new libraries for modelling HVAC systems, automobile systems and buildings, and research results for new solvers. An important trend is virtual modelling and simulation of building thermodynamics (scaling up to city districts), automotive systems (autonomous vehicles), and especially Factory Automation: Dassault is investing heavily in this area, focusing on smaller customers, with tools for 3D virtual modelling of assembly lines including machine dynamics (robotics), and in partnerships with Siemens and other European FA companies.
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- Date: September 17, 2015
MERL Contacts: Stefano Di Cairano; Scott A. Bortoff; Abraham Goldsmith Brief - MERL researchers presented 3 papers at the 5th IFAC Nonlinear Model Predictive Control Conference. Approximately 150 attendees. Conference topics range from theory (existence, stability), to algorithms (optimization, design), to applications (process control, mechatronics, energy, automotive, aerospace). MERL was an industry sponsor for the conference. MERL researcher co-chaired the Industry Session on Industry perspective on Model Predictive Control. MERL researcher acted as Program Co-chair, organizing the conference program.
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- Date: July 9, 2013
Where: International Journal of Control
MERL Contacts: Stefano Di Cairano; Matthew Brand; Scott A. Bortoff
Research Area: Control
Brief - The article "Projection-free Parallel Quadratic Programming for Linear Model predictive Control" by Di Cairano, S., Brand, M. and Bortoff, S.A. was published in International Journal of Control.
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- Date: June 17, 2013
Where: American Control Conference (ACC)
MERL Contacts: Scott A. Bortoff; Stefano Di Cairano; Yebin Wang; Arvind Raghunathan Brief - The papers "Sub-optimal Control Design of a Semi-active Vibration Reduction System" by Wang, Y. and Utsunomiya, K., "Adaptive Estimation of State of Charge for Lithium-ion Batteries" by Fang, H., Wang, Y., Sahinoglu, Z., Wanda, T. and Hara, S., "Vehicle Yaw Dynamics Control by Torque-based Assist Systems Enforcing Driver's Steering Feel Constraints" by Zafeiropoulos, S. and Di Cairano, S., "Speed Profile Optimization for Optimal Path Tracking" by Zhao, Y. and Tsiotras, P., "Real-Time Energy-Optimal Trajeactory Generatin for a Servo Motor" by Zhao, Y., Wang, Y., Bortoff, S.A. and Ueda, K., "Global Optimization of Multi-period Optimal Power Flow" by Gopalakrishnan, A., Raghunathan, A.U., Nikovski, D., Biegler, L.T. and "Semismooth Equation Approach to Network Utility Maximization (NUM)" by Bai, L. and Raghunathan, A.U. were presented at the American Control Conference (ACC).
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- Date: December 10, 2012
Where: IEEE Annual Conference on Decision and Control (CDC)
MERL Contacts: Stefano Di Cairano; Scott A. Bortoff; Yebin Wang Brief - The papers "A Numerical Algorithm for Nonlinear L2-gain Optimal Control with Application to Vehicle Yaw Stability Control" by Milic, V., Di Cairano, S., Kasac, J., Bemporad, A. and Situm, Z., "The Rendezvous Dynamics under Linear Quadratic Optimal Control" by Di Cairano, S., Pascucci, C.A. and Bemporad, A. and "On the Optimal Trajectory Generation for Servomotors: A Hamiltonian Approach" by Wang, Y., Ueda , K. and Bortoff, S.A. were presented at the IEEE Annual Conference on Decision and Control (CDC).
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- Date & Time: Wednesday, August 1, 2012; 12:00 PM
Speaker: Prof. Prashant Mehta, University of Illinois at Urbana-Champaign
MERL Host: Scott A. Bortoff Abstract - In my talk, I will present a self-contained introduction to nonlinear filtering, and describe some recent developments. Specifically, I will introduce the feedback particle filter and show how it admits an innovations error-based feedback control structure. The control is chosen so that the posterior distribution of any particle matches the posterior distribution of the true state given the observations. The subject of my talk is a new formulation of nonlinear filter (for Bayesian inference) that is based on concepts from optimal control and mean-field game theory. Nonlinear filtering is important to many applications in engineering, biology, economics, atmospheric sciences and neuroscience. Several applications will be described to illustrate the theoretical concepts.
This is joint work with Tao Yang and Sean Meyn at the University of Illinois.
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- Date: Thursday, July 19, 2012
Speaker: Rick Vaccaro, University of Rhode Island
MERL Host: Scott A. Bortoff Abstract - The ability to directly specify the closed-loop poles of a multivariable control system is a major benefit of pole-placement algorithms for calculating state-feedback and observer gains. The drawback of these algorithms is the lack of any guarantee on the stability robustness of the resulting control system. The optimal control approach for calculating state-feedback gains (LQR) has a certain guaranteed robustness, but adding an observer (i.e. Kalman filter, LQG) can result in arbitrarily poor robustness. In this talk, a new pole-placement approach is introduced for calculating state-feedback and observer gains. The new approach optimizes robustness and gives impressive results, particularly for output feedback, observer-based control systems.
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- Date & Time: Wednesday, June 27, 2012; 12:00 PM - 1:30 PM
Location: Montreal, Canada
MERL Contact: Scott A. Bortoff Brief - In this session, MERL researcher Scott Bortoff will describe Mitsubishi Electric Corporation (MELCO)'s businesses, discuss mechatronics and controls research at MERL and describe opportunities for collaboration and employment. Areas of current research interest include optimal control especially of nonlinear and hybrid systems, model predictive control, nonlinear dynamical systems, and modeling and control of multi-physical heterogeneous systems. Research projects at MERL typically address fundamental problems that are industrially-motivated, and involve application of advanced control theory or dynamical systems theory to MELCO products resulting in new technology that is transferred into the corporate R&D laboratories for subsequent product development. Areas of current application include elevators, HVAC, power generation and distribution, satellites, robot manipulation, servo systems and laser processing systems. MERL has a tradition of open collaboration and hosts visitors and interns especially during the summer months when our population increases by 50%. Researchers and students who have an interest in collaboration, visits, sabbatical leaves or permanent employment are invited.
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- Date: June 27, 2012
Where: American Control Conference (ACC)
MERL Contacts: Stefano Di Cairano; Scott A. Bortoff Brief - The papers "Further Developments and Applications of Network Reference Governor for Constrained Systems" by Di Cairano, S. and Kolmanovsky, I.V. and "Load Positioning in the Presence of Base Vibrations" by Shilpiekandula, V., Bortoff, S.A., Barnwell, J.C. and El Rifai, K. were presented at the American Control Conference (ACC).
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- Date: August 28, 2011
Where: World Congress of the International Federation of Automatic Control (IFAC)
MERL Contacts: Scott A. Bortoff; Matthew Brand Brief - The papers "Integrated Design and Control of Flexure-Based Nanopositioning Systems - Part I: Methodology" by Shilpiekandula, V. and Youcel-Toumi, K. and "A Parallel Quadratic Programming Algorithm for Model Predictive Control" by Brand, M., Shilpiekandula, V. and Bortoff, S.A. were presented at the World Congress of the International Federation of Automatic Control (IFAC).
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- Date: July 22, 2011
Where: Chinese Control Conference (CCC)
MERL Contacts: Yebin Wang; Scott A. Bortoff
Research Area: Control
Brief - The paper "Nonlinear Control Design for a Semi-active Vibration Reduction System" by Wang, Y., Utsunomiya, K. and Bortoff, S.A. was presented at the Chinese Control Conference (CCC).
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- Date: July 15, 2010
Where: IASTED International Conference on Control and Applications
MERL Contacts: Yebin Wang; Scott A. Bortoff
Research Area: Control
Brief - The paper "On the Output Transformation to an Observer Form" by Wang, Y., Lynch, A.F. and Bortoff, S.A. was presented at the IASTED International Conference on Control and Applications.
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