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Events

• Apr

  2

  Nelson and Nemhauser Best Paper Award Seminar

  Department of Industrial Engineering and Management Sciences (IEMS)

  11:00 AM A230, Technological Institute

  EVENT DETAILS

  Students from the IEMS department will present a seminar based on their award winning papers

  AKHIL SINGLA

  Title: Optimal Control of Join Decision in Fork-Jon Queues

  Abstract: In fork-join (FJ) queues, each incoming job to the system is copied and sent to all its parallel servers. A job is completed when all or some of the copies are processed by parallel servers. These FJ queues are prevalent in diverse domains of service operations like fact-checking for social media platforms, hospital diagnosis operations, legal systems etc. FJ queueing systems can capture the trade-off between speed and accuracy that commonly arises in knowledge-based service systems. In this paper, we study the optimal control of “join decision” in FJ queues. A join decision determines how many copies of a job should be processed before the job leaves the system. We fully characterize the structure of the optimal dynamic join decision policy with respect to the parameters that affect the trade-off between speed and accuracy. To overcome the curse of dimensionality, we propose an intuitive, easy-to-compute and easy-to-implement heuristic policy that uses total number of jobs in the system to make join decision. This heuristic is shown to perform within 2% optimality gap and performs better than some commonly used benchmark policies. The heuristic policy also allows managers to achieve a desired service-level that balances speed and accuracy of the operations.

  SHIMA DEZFULIAN

  Title: Derivative-Free Bound-Constrained Optimization for Solving Structured Problems with Surrogate Models

  Abstract: We propose and analyze a model-based derivative-free (DFO) algorithm for solving bound-constrained optimization problems where the objective function is the composition of a smooth function and a vector of black-box functions. We assume that the black-box functions are smooth and the evaluation of them is the computational bottleneck of the algorithm. The distinguishing feature of our algorithm is the use of approximate function values at interpolation points which can be obtained by an application-specific surrogate model that is cheap to evaluate. As an example, we consider the situation in which a sequence of related optimization problems is solved and present a regression-based approximation scheme that uses function values that were evaluated when solving prior problem instances. In addition, we propose and analyze a new algorithm for obtaining interpolation points that handles unrelaxable bound constraints. Our numerical results show that our algorithm outperforms a state-of-the-art DFO algorithm for solving a least-squares problem from a chemical engineering application when a history of black-box function evaluations is available.

  XIAOCHUN NIU

  Title: Exact Community Recovery in the Geometric SBM

  Abstract: We study the problem of exact community recovery in the Geometric Stochastic Block Model (GSBM), where each vertex has an unknown community label as well as a known position, generated according to a Poisson point process in the d-dimensional euclidean space. Edges are formed independently conditioned on the community labels and positions, where vertices may only be connected by an edge if they are within a prescribed distance of each other. The GSBM thus favors the formation of dense local subgraphs, which commonly occur in real-world networks, a property that makes the GSBM qualitatively very different from the standard Stochastic Block Model (SBM). We propose a linear-time algorithm for exact community recovery, which succeeds down to the information-theoretic threshold, confirming a conjecture of Abbe, Baccelli, and Sankararaman. The algorithm involves two phases. The first phase exploits the density of local subgraphs to propagate estimated community labels among sufficiently occupied subregions, and produces an almost-exact vertex labeling. The second phase then refines the initial labels using a Poisson testing procedure. Thus, the GSBM enjoys local to global amplification just as the SBM, with the advantage of admitting an information-theoretically optimal, linear-time algorithm.

  YUCHEN LOU

  Title: Noise-Tolerant Optimization Methods for the Solution of a Robust Desing Problem

  Abstract: The development of nonlinear optimization algorithms capable of performing reliably in the presence of noise has garnered considerable attention lately. This motivates the questions of whether well-established methods in the literature can be modified to cope with noise, and whether they are applicable in real-world problems. This paper advocates for strategies to create noise-tolerant nonlinear optimization algorithms by adapting classical deterministic methods. These adaptations follow certain design guidelines described in this work, which make use of estimates of the noise level in the problem. The application of our methodology is illustrated by the development of a line search gradient projection method, which is tested on a practical engineering design problem. It is shown that a new self-calibrated line search and noise-aware finite-difference techniques are effective even in the high noise regime. Numerical experiments with a systematic design investigate the resiliency of key algorithmic components. A convergence analysis of the line search gradient projection method establishes convergence to a neighborhood of the solution.

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  TIME Tuesday, April 2, 2024 at 11:00 AM - 12:00 PM

  LOCATION A230, Technological Institute    map it

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  CONTACT Kendall Minta    kendall.minta@gmail.com EMAIL

  CALENDAR Department of Industrial Engineering and Management Sciences (IEMS)

• Apr

  30

  Learning and Information Aggregation in Dynamic Games

  Department of Industrial Engineering and Management Sciences (IEMS)

  11:00 AM ITW 1.350, Ford Motor Company Engineering Design Center

  EVENT DETAILS

  Abstract: Many competitive situations can be represented as dynamic stochastic games in which there is an unobserved state that affects the players’ payoffs. Players try to learn both the environment and their competitors’ strategies. Without competition, to learn the environment, a player needs exploration and more information is always beneficial. This talk will discuss how competition can significantly change the structure of optimal policies and lead to the players’ optimally not learning the environment.

  Bio: John R. Birge is the Hobart W. Williams Distinguished Service Professor of Operations Management at the University of Chicago Booth School of Business. He studies mathematical modeling of systems under uncertainty, especially for maximizing operational and financial goals using the methodologies of stochastic programming and large-scale optimization. He has applied his work in a variety of contexts and industries including energy, finance, health care, manufacturing, and transportation. He has published widely and is the recipient of the Best Paper Award from the Japan Society for Industrial and Applied Mathematics, the Institute for Operations Research and the Management Sciences Fellows Award, the Institute of Industrial Engineers Medallion Award and was elected to the National Academy of Engineering.

  A former dean of the Robert R. McCormick School of Engineering and Applied Sciences at Northwestern University, he has worked as a consultant for a variety of firms including the University of Michigan Hospitals, Deutsche Bank, Allstate Insurance Company, and Morgan Stanley.

  Birge earned a bachelor's degree in mathematics from Princeton University in 1977 and a master's degree and a PhD in operations research from Stanford University in 1979 and 1980, respectively.

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  TIME Tuesday, April 30, 2024 at 11:00 AM - 12:00 PM

  LOCATION ITW 1.350, Ford Motor Company Engineering Design Center    map it

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  CONTACT Kendall Minta    kendall.minta@gmail.com EMAIL

  CALENDAR Department of Industrial Engineering and Management Sciences (IEMS)

• May

  8

  Extending Care: A Conversation about Conservation and Futurity

  Block Museum of Art

  6:00 PM Block Museum of Art, Mary and Leigh

  EVENT DETAILSmore info

  The Center for Scientific Studies in the Arts is a collaboration between the Art Institute of Chicago and materials science-related departments at Northwestern University to pursue objects-based and objects-inspired scientific research. Materials research benefits ongoing work in conservation, archaeology, art history, and curatorial scholarship.

  Learn how the Center uses materials research to care for art objects in sustainable, innovative ways with Maria Kokkori, Senior Scientist in the Center for Scientific Studies in the Arts. She will be in conversation with Corey Byrnes, Northwestern Associate Professor of Chinese Culture and co-founder/co-director of the Environmental Humanities Workshop in Kaplan Humanities Center.

  This event is presented by the McCormick School of Engineering and Applied Science in conjunction with exhibition Actions for the Earth: Art, Care & Ecology.

  Register Now

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  TIME Wednesday, May 8, 2024 at 6:00 PM - 7:30 PM

  LOCATION Block Museum of Art, Mary and Leigh    map it

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  CONTACT Block Museum of Art    block-museum@northwestern.edu EMAIL

  CALENDAR Block Museum of Art

• Jun

  10

  Northwestern Engineering PhD Hooding and Master's Degree Recognition Ceremony

  McCormick School of Engineering and Applied Science

  9:00 AM Welsh-Ryan Arena

  EVENT DETAILSmore info

  McCormick School of Engineering PhD Hooding and Master’s Degree Recognition Ceremony

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  TIME Monday, June 10, 2024 at 9:00 AM - 11:00 AM

  LOCATION Welsh-Ryan Arena   

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  CONTACT Amy Pokrass    amy.pokrass@northwestern.edu EMAIL

  CALENDAR McCormick School of Engineering and Applied Science

• Jun

  10

  Northwestern Engineering Undergraduate Convocation

  McCormick School of Engineering and Applied Science

  2:00 PM Welsh-Ryan Arena

  EVENT DETAILSmore info

  McCormick School of Engineering Undergraduate Convocation

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  TIME Monday, June 10, 2024 at 2:00 PM - 4:00 PM

  LOCATION Welsh-Ryan Arena   

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  CONTACT Amy Pokrass    amy.pokrass@northwestern.edu EMAIL

  CALENDAR McCormick School of Engineering and Applied Science

• Aug

  14

  Undergraduate Quantum Summer School

  McCormick School of Engineering and Applied Science

  All Day Ford Motor Company Engineering Design Center

  EVENT DETAILSmore info

  Innovation in Quantum Pedagogy, Application, and its Relation to Culture (IQ-PARC), funded by the Department of Defense — National Defense Education Program, is extending an invitation to underrepresented students nationwide (including military-connected students) to participate in a summer school focused on quantum technologies, to be held at Northwestern University. Join us for presentations by faculty and industry partners introducing quantum technologies, cutting-edge research areas, and related job opportunities particularly in the areas of national security.

  This effort aims to foster an inclusive environment that encourages participation from all corners of the academic community. Successful applicants will receive up to $1,000 USD to cover travel and lodging expenses in Evanston, IL.

  Priority application deadline: May 15, 2024.

  Decisions will be sent by June 15, 2024.

  Register Now

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  TIME Wednesday, August 14, 2024

  LOCATION Ford Motor Company Engineering Design Center    map it

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  CONTACT Dongyang Li    lidongyang@northwestern.edu EMAIL

  CALENDAR McCormick School of Engineering and Applied Science

• Aug

  15

  Undergraduate Quantum Summer School

  McCormick School of Engineering and Applied Science

  All Day Ford Motor Company Engineering Design Center

  EVENT DETAILSmore info

  Innovation in Quantum Pedagogy, Application, and its Relation to Culture (IQ-PARC), funded by the Department of Defense — National Defense Education Program, is extending an invitation to underrepresented students nationwide (including military-connected students) to participate in a summer school focused on quantum technologies, to be held at Northwestern University. Join us for presentations by faculty and industry partners introducing quantum technologies, cutting-edge research areas, and related job opportunities particularly in the areas of national security.

  This effort aims to foster an inclusive environment that encourages participation from all corners of the academic community. Successful applicants will receive up to $1,000 USD to cover travel and lodging expenses in Evanston, IL.

  Priority application deadline: May 15, 2024.

  Decisions will be sent by June 15, 2024.

  Register Now

  more less

  TIME Thursday, August 15, 2024

  LOCATION Ford Motor Company Engineering Design Center    map it

  ADD TO CALENDAR

  CONTACT Dongyang Li    lidongyang@northwestern.edu EMAIL

  CALENDAR McCormick School of Engineering and Applied Science