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Events
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Apr15
EVENT DETAILS
Title: Phase-Amplitude-Based Techniques for Control and Analysis of Strongly Perturbed Limit Cycle Oscillators
Speaker: Dan Wilson, University of Tennessee, Knoxville
Abstract: While phase-based reduction techniques have a rich history in the analysis and control of oscillatory dynamical systems, the overwhelming majority of theoretical analysis in this field has been performed in the weakly perturbed limit. Comparatively very little is understood about limit cycle oscillators in response to strong and/or long-lasting perturbations, mostly due to the lack of viable reduction strategies that are valid when considering strong perturbations. In this presentation, I will discuss the use of isostable coordinates, which characterize level sets of the slowest decaying eigenmodes of the Koopman operator in conjunction with phase-based techniques to yield analytically tractable reduced order models that are valid in the strongly perturbed regime. Applications involving phase resetting of circadian rhythms following rapid travel across multiple time zones illustrate the utility of these new methods in situations where standard, phase-only techniques fail. I will also discuss related work motivated by experimental and detailed computational studies finding that coupled circadian oscillators with decreased levels of synchronization are able to more rapidly adjust to changes in circadian time. Theoretical analysis reveals the dynamics of mean-field coupled oscillators can be considered in the context of a supercritical Hopf bifurcation, ultimately providing an explanation for the fundamental relationship between synchronization and phase resetting efficiency. In the context of jet-lag recovery strategies, further analysis reveals that transient desynchronization facilitates phase resetting when the relaxation rate of the population limit cycle is sufficiently slow relative to the natural frequency of the population oscillation.
Zoom: https://northwestern.zoom.us/j/91324444590
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TIME Tuesday, April 15, 2025 at 11:15 AM - 12:15 PM
LOCATION M416, Technological Institute map it
CONTACT Ted Shaeffer ted.shaeffer@northwestern.edu EMAIL
CALENDAR McCormick-Engineering Sciences and Applied Mathematics (ESAM)
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Apr22
EVENT DETAILS
Title: Control for Embodied Learning
Speaker: Todd Murphey, Northwestern University
Abstract: Embodied learning systems rely on motion synthesis to enable efficient and flexible learning during continuous online deployment. Motion motivated by learning needs can be found throughout natural systems, yet there is surprisingly little known about synthesizing motion to support learning for robotic systems. Moreover, robotic systems will need to collect data autonomously for learning, for instance when isolated for long period of time or when encountering novel environmental features. Learning goals create a distinct set of control-oriented challenges, including how to choose measures as objectives, synthesize real-time control based on these objectives, impose physics-oriented constraints on learning, and produce analyses that certify performance and safety with limited knowledge. This talk will discuss learning tasks that robots encounter, abstractions that enable regulating information content of observations, and recent progress on algorithms for generating action plans that facilitate learning.
Zoom: https://northwestern.zoom.us/j/96919208870
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TIME Tuesday, April 22, 2025 at 11:15 AM - 12:15 PM
LOCATION M416, Technological Institute map it
CONTACT Ted Shaeffer ted.shaeffer@northwestern.edu EMAIL
CALENDAR McCormick-Engineering Sciences and Applied Mathematics (ESAM)
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May12
EVENT DETAILS
Title: In Search of Internal Models - Reiss Lecture
Speaker: Adrienne Fairhall, University of Washington
Abstract: How do we build the mental models that we use to perceive, navigate and reason about the world? How might these models be inferred from neural activity? I will describe experiments and analysis in collaboration with Beth Buffalo's lab to explore these questions in our closest relatives, nonhuman primates. In one example, we compare monkey and human behavior in a decision task, and analyze how subjects make use of visual information and feedback to infer a hidden rule, where the rule switches in an uncued fashion. We fit a suite of behavioral models and learn that while humans are close to optimal Bayesian agents, monkey behavior is better fit as reinforcement learning. This allows us to seek neural implementations of this internal belief update. Further, while rodent hippocampus famously encodes the animal's spatial location, we find evidence that hippocampus in the primate serves a more cognitive role.
Zoom: TBA
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TIME Monday, May 12, 2025 at 4:00 PM - 5:00 PM
LOCATION Hive Room 2350, Ford Motor Company Engineering Design Center map it
CONTACT Ted Shaeffer ted.shaeffer@northwestern.edu EMAIL
CALENDAR McCormick-Engineering Sciences and Applied Mathematics (ESAM)
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May13
EVENT DETAILS
Title: Decoding Neurons to Behavior in a Model Organism - Reiss Lecture
Speaker: Adrienne Fairhall, University of Washington
Abstract: The freshwater cnidarian Hydra is a fascinating model organism for neuroscience. It is transparent; new genetic lines allow one to image activity in both neurons and muscle cells; it exhibits a quite rich suite of behaviors; and it continually rebuilds itself. Hydra’s fairly simple physical structure as a two-layered fluid-filled hydrostat and the accessibility of information about neural and muscle activity open the possibility of a complete model of neural control of behavior. We have developed a biophysical and biomechanical model of Hydra's muscles and body that allows us to transform measured neural activity into behavior. We also propose a model for how the neural network rebuilds as the animal regenerates itself following bisection.
Zoom: TBA
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TIME Tuesday, May 13, 2025 at 4:00 PM - 5:00 PM
LOCATION Hive Room 2350, Ford Motor Company Engineering Design Center map it
CONTACT Ted Shaeffer ted.shaeffer@northwestern.edu EMAIL
CALENDAR McCormick-Engineering Sciences and Applied Mathematics (ESAM)
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May27
EVENT DETAILS
Title: Two Tales, One Resolution: Physics-Informed Test Time Scaling and Precondition
Speaker: Yiping Lu, Northwestern University
Abstract: In this talk, I will introduce a novel framework for physics-informed debiasing of machine learning estimators, which we call Simulation-Calibrated Scientific Machine Learning (SCaSML). This approach leverages the structure of physical models to achieve two key objectives:
Unbiased Predictions: It produces unbiased predictions even when the underlying machine learning predictor is biased.
Overcoming Dimensionality Challenges: It mitigates the curse of dimensionality that often affects high-dimensional estimators.The SCaSML paradigm integrates a (potentially) biased machine learning algorithm with a de-biasing procedure that is rigorously designed using numerical analysis and stochastic simulation. Our methodology aligns with recent advances in inference-time computation—similar to those seen in the large language model literature—demonstrating that additional computation can enhance ML estimates. Furthermore, we establish a surprising equivalence between our framework and another research direction that utilizes approximate (linearized) solvers to precondition iterative methods. This connection not only bridges two distinct areas of study but also offers new insights into improving estimation accuracy in complex, high-dimensional (PDE) settings.
Zoom: https://northwestern.zoom.us/j/94570889326
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TIME Tuesday, May 27, 2025 at 11:15 AM - 12:15 PM
LOCATION M416, Technological Institute map it
CONTACT Ted Shaeffer ted.shaeffer@northwestern.edu EMAIL
CALENDAR McCormick-Engineering Sciences and Applied Mathematics (ESAM)
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Jun15
EVENT DETAILSmore info
2024-2025 Commencement Ceremony
TIME Sunday, June 15, 2025
CONTACT Office of the Registrar nu-registrar@northwestern.edu EMAIL
CALENDAR University Academic Calendar
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Jun16
EVENT DETAILS
McCormick School of Engineering PhD Hooding and Master's Degree Recognition Ceremony. The most up to date information can be found on our graduation webpage.
TIME Monday, June 16, 2025 at 9:00 AM - 11:00 AM
LOCATION 2705 Ashland Ave
CONTACT Northwestern Engineering Events northwestern-engineering-events@northwestern.edu EMAIL
CALENDAR McCormick School of Engineering and Applied Science
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Jun16
EVENT DETAILSmore info
McCormick School of Engineering Undergraduate Convocation. The most up to date information can be found on our graduation webpage.
TIME Monday, June 16, 2025 at 2:00 PM - 4:00 PM
LOCATION 2705 Ashland Ave
CONTACT Northwestern Engineering Events northwestern-engineering-events@northwestern.edu EMAIL
CALENDAR McCormick School of Engineering and Applied Science