Systems and Control
Tethered UAVs for Dense Urban Connectivity
German Svistunov and Azim Akhtarshenas
This paper evaluates the downlink performance of 5G non-terrestrial networks (NTNs) realized via tethered unmanned aerial vehicle (TUAV)-mounted base stations, and compares it against conventional 5G terrestrial networks (TNs) in a realistic dense urban scenario. Unlike battery-limited
UAVs, TUAVs are connected to ground stations via lightweight cables, enabling stable positioning and near-line-of-sight links to users without the endurance constraints of untethered platforms. Using a 3GPP-compliant multi-
cell hexagonal layout with 19 sites and 57 sectors, we model TUAV altitudes ranging from 100 to 1000\,m and evaluate the average effective signal-to-interference-plus-noise ratio (SINR) and user throughput via system-level simulations. Results show that TUAV-based NTN deployments can significantly outperform terrestrial 5G in per-user throughput, with the largest gains observed for
cell-edge and low-SINR users, provided the TUAV altitude is properly chosen to balance improved line-of-sight probability against increased propagation loss and interference at higher altitudes.
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Systems and Control
Economic Evaluation of V2G-Enabled Fast Charging Stations Under Endogenous EV Adoption Dynamics
Mingjian Tuo, Jie Zhou, Yao Yan et al. (+3 more)
Building fast charging stations (FCSs) is crucial for transportation electrification, but there exists an indirect network effect: while the increasing number of electric vehicles (EVs) decides the FCS capacity expansion, the spatial locations of these facilities strongly influence drivers' willingness to adopt EVs. Ignoring this interaction can lead to bad capital investments and exacerbate power grid vulnerabilities during tidal traffic peaks. Therefore, we explicitly model the EV adoption dynamics as decision-dependent uncertainties (DDUs) in a new multi-period collaborative planning framework. This framework evaluates the economic viability of V2G-enabled FCSs across both transportation and distribution networks. To simplify the complex calculation, we introduce an aggregated fleet virtual battery model to catch macroscopic vehicle-to-grid (V2G) flexibility. This successfully circumvents the dimension curse inherent in tracking microscopic state-of-charge. To further guarantee calculation speed, the nonlinear infrastructure exposure is transformed into a mixed-integer program by using Special Ordered Set type 2 (SOS2) variables and Second-Order Cone Programming (SOCP) relaxations for grid limits. Finally, numerical studies on a coupled Sioux Falls and IEEE 33-bus testbed prove that our framework achieves superior expected social welfare. Also, macroscopic V2G aggregation is highlighted for its capability to mitigate distribution grid congestion penalties.
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All authors Mingjian Tuo, Jie Zhou, Yao Yan, Cunzhi Zhao, Long Wang, Mulan Zhang
Systems and Control · Cross-listed from cs.IT
Frame-Coded Legged Locomotion over Noisy Terrain
Lav R. Varshney
Open-loop multilegged locomotion over rough terrain has been interpreted as matter transport over a noisy channel: leg-ground interactions are discrete basic active contacts, terrain deletes or perturbs those contacts, and spatial redundancy concentrates the resulting thrust and arrival time. That construction is repetition-like because every module carries the same scalar locomotion task. It consequently provides neither a positive task rate nor a decoder that changes with the surviving contact set. Here we formulate locomotion instead as a quantized finite-frame expansion with erasures. A d-dimensional body-level command is mapped into N>d heterogeneous local contact commands. Rough terrain erases or corrupts frame coefficients, while a contact-gated compliant morphology physically realizes the weighted active-subframe decoder. For a linear-Gaussian model, mechanical
equilibrium is exactly the posterior mean, tangent stiffness is posterior precision, and mechanical compliance is posterior covariance. Equal-norm Parseval frames are shown to be minimax optimal against one missing contact, two-contact robustness is governed by frame coherence, and a harmonic frame gives a directly realizable gait family. For independently surviving contacts of probability q, random Gaussian gait frames admit exact reconstruction at every analog dimension rate R<q, with a binomial reliability exponent, whereas recovery of arbitrary commands is impossible for R>q. Residual contact noise yields an asymptotic per-mode amplification 1/(q-R) and a vanishing mechanical stiffness margin at the threshold. An information-locomotion inequality and an exact incremental-redundancy rule direct the next gait component toward the softest task-relevant unresolved mode. The resulting analog frame-coding
theorem establishes a finite relative redundancy and converse as part of a fundamental limit theory of legged locomotion.
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Systems and Control
Mitigating Degradation Attacks in Cooperative Autonomous Driving via Intention Sharing: A Vehicle-in-the-Loop Study
Prakhar Gupta, Tyler Ard, Rongyao Wang et al. (+4 more)
Communication delays induced by cyber attacks present a critical challenge to the safe operation of connected autonomous driving. This study investigates the use of intention sharing communication strategy to enhance the resilience of model predictive controllers under Denial-of-Service attacks. We employ a vehicle-in-the-loop testbed integrating a real drive-by-wire vehicle with a microscopic traffic simulator and vehicle-to-X communication infrastructure. We emulate Denial-of-service attacks that induce communication delays of up to two seconds. We evaluate three controller variants: baseline status-sharing, intention-sharing, and delay-aware intention-sharing control. Experimental results reveal that while baseline control suffers significant performance degradation and frequent collisions under
adversarial delay, intention sharing eliminates collisions and maintains behavior near nominal levels for the tested scenarios. These findings demonstrate the practical potential of intention-sharing architectures for safeguarding connected vehicles against network-layer degradation.
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All authors Prakhar Gupta, Tyler Ard, Rongyao Wang, Jagruti Sahoo, Judith Mwakalonge, Ardalan Vahidi, Yunyi Jia
Systems and Control · Cross-listed from cs.RO
CougarTail & CUB: A General-Purpose Mast and Central Utility Board for Cylindrical Underwater Enclosures
Ben Washburn, Clayton Smith, Eli Gaskin et al. (+4 more)
Cylindrical watertight enclosures are widely used across various underwater systems, from unmanned underwater vehicles (UUVs), to remotely operated vehicles (ROVs), to various sensor platforms. However, electronics are typically built on rectangular PCBs arranged in horizontal stacks, which inefficiently occupy the circular cross-section volume that is critical for both payload capacity and buoyancy management. This paper presents CUB (Central Utility Board) and CougarTail, a general-purpose system designed to address this gap. CUB is a circular PCB sized for 4-inch-diameter enclosures that consolidates a Raspberry Pi Compute Module 5 (CM5) and an STM32 microcontroller, while also providing power management features and auxiliary connections. Mounted coaxially, CUB reduces the electronics stack of our CougUV from 200 mm of tube length and 709 g to 25 mm and 156 g, returning that length and mass budget to payload and buoyancy trim. CougarTail is an open-source companion sensor mast that houses a GPS
antenna and two dual-band (2.4 and 5 GHz) omnidirectional PCB
antennas. Both components are validated through bench testing and integration on a CougUV platform, our small open-sourced torpedo UUVs.
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All authors Ben Washburn, Clayton Smith, Eli Gaskin, Brighton Anderson, Braden Meyers, Brady Moon, Joshua Mangelson
Systems and Control · Cross-listed from cs.RO
Adaptive Shared Control with Online Bounded-Rational Human Behavior Estimation
Henry Ascencio Trejo, Roel Pieters and Gokhan Alcan
This work considers adaptive shared human-
robot control for nonlinear control-affine systems, where the assumption of a fully rational human is relaxed and the
robot adapts its assistance to observed boundedly rational human behavior. We use a level-k bounded-rationality model of the two-player game to construct a finite bank of candidate human and
robot policies through alternating best-response computations, with the associated value functions and policies approximated using adaptive dynamic programming. During the shared-control interaction, state-transition residuals compare the measured system
evolution with the trajectories predicted by the candidate human policies. The residuals are accumulated using a forgetting factor and mapped to a probabilistic human-behavior model over the finite candidate bank. Rather than selecting a single candidate or averaging stored
robot policies, the
robot computes a distribution-aware one-step best response by minimizing an expected cooperative cost over the complete estimated human behavior distribution. For a quadratic terminal-value approximation and Euler state propagation, this response admits a closed-form solution expressed in terms of the expected human input. The proposed methods are evaluated in simulations of a
benchmark nonlinear system stabilization task, and of a planar manipulator shared control setup. The reported results show decreasing Kullback-Leibler divergence between the estimated and simulated human behavior distributions, and a lower accumulated running cost for the
robot agent over the shared control interaction period, than the maximum-probability and probability-weighted alternative policies baseline.
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Systems and Control
IMU-Centric Moving Horizon Estimation for Lateral Dynamics Estimation Across Vehicles and Grip Conditions
Seuffo Akouan ha Ngoune, Alessandro Toschi, Paolo Burgio et al. (+1 more)
Accurate estimation of lateral vehicle dynamics near the adhesion limit is important for stability control and high-performance driving, but lateral velocity is rarely measured directly because sensors such as optical sensors are costly. This paper presents an inertial measurement unit (IMU)-centric Moving Horizon Estimation framework that reconstructs lateral velocity using standard onboard signals, without relying on exteroceptive odometry or detailed tire-parameter tuning. Experimental validation on human-driven sports cars and an autonomous open-wheel race car across tracks, maneuvers, and conditions demonstrates accurate and robust lateral velocity and lateral acceleration estimates. The proposed framework is available at https://github.com/Aseuffo/IMU-Centric-MHE
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All authors Seuffo Akouan ha Ngoune, Alessandro Toschi, Paolo Burgio, Marko Bertogna
Systems and Control
From Laboratory Aging Studies to Field Predictions: Quantifying Uncertainty in Battery Storage Lifetime Predictions
Melina Graner, Jan Figgener, Andreas Jossen et al. (+1 more)
Predicting how long a battery energy storage system will last is critical for warranty design, maintenance planning and investment decisions, yet degradation models are mostly deterministic and rarely validated against real field data. We apply an open-source probabilistic degradation framework, combined with a
cell-to-system approximation, to bridge the gap between
cell-level laboratory aging models and system-level field predictions for residential battery energy storage systems with quantified uncertainty. The framework predicts
cell-level state-of-health to within 0.4 % mean absolute error, roughly half the error of prior models for this
dataset. When applied to field operation data, the framework's predictions are consistent with all three available system-level capacity measurements - a
benchmark rarely available for open probabilistic degradation models.
Cell-level heterogeneity is approximated by two bounding stress scenarios differing only slightly (a 5 % spread in temperature and a 9 % spread in current). The mean degradation trajectories of the two scenarios reach end-of-life 10 months apart, while the full predicted end-of-life range across both scenarios spans approximately three years, about a third of the expected system lifetime. We link this uncertainty to two drivers. One is a systematic mismatch between laboratory test conditions and field-representative operating stress. The other is variability in the training data itself. These insights translate into concrete, resource-efficient recommendations for future aging study design, supporting more confident predictions of battery lifetime under real-world conditions.
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All authors Melina Graner, Jan Figgener, Andreas Jossen, Holger Hesse
Systems and Control · Cross-listed from eess.SP
Distributed ToA Localization of Acoustic Sources with Unknown Time of Emission via Operator Splitting
Anton Tolstonogov, David Cabecinhas, Pedro Batista et al. (+1 more)
Localization of non-cooperative acoustic sources using multiple spatially distributed receivers is critical for applications such as marine-life tracking, search-and-rescue operations, and maritime security in underwater environments. In conventional Time of Arrival (ToA) systems, the emission time is typically known explicitly or implicitly through clock synchronization or two-way communication, so the problem reduces to range-based localization. In passive settings, however, only reception timestamps are available. Thus, the emission time must be eliminated through Time Difference of Arrival (TDoA) preprocessing or estimated jointly with the source position. For the case of a single source, we address the distributed localization problem over a receiver network by reformulating passive localization directly as a ToA problem with unknown time of signal emission. This yields a distributed consensus optimization problem, which we solve using an operator-splitting method, namely an edge-based Distributed Alternating Direction Method of Multipliers (DADMM) scheme that decomposes the estimation task into local subproblems coupled through agreement constraints. We derive closed-form local update equations for the local DADMM subproblems and establish convergence properties for a smoothed approximation of the measurement model. Numerical simulations illustrate the efficacy of the proposed approach.
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All authors Anton Tolstonogov, David Cabecinhas, Pedro Batista, Antonio Pascoal
Systems and Control · Cross-listed from cs.NI
Can AI Agents Deliver Verifiable Network-Wide Outcomes Across Authority Boundaries?
Tianzhu Zhang, Chih-Kai Huang and Meikang Qiu
AI
agents are increasingly involved in network automation, where they can initiate configuration changes through mediated operational interfaces and assess the resulting state. Nonetheless, operational networks usually span many devices and administrative domains. Realizing an operator's intent requires coordinating
agents with distinct authority scopes that define the resources they can access, the operations they can invoke, and the network state they can observe. This division limits the blast radius of an erroneous action but fragments the evidence needed to assess the network-wide outcome. Successful execution of a configuration action proposed by one
agent does not establish that remote devices responded as intended or that routing changes reached the required devices. A valid observation may also become stale after a subsequent change. Before the coordinated operation can be declared complete, a trusted assurance layer must collect current observations from the required scopes and determine whether they collectively support the operator's intended network-wide outcome. To address the completion admission problem, we present EvidenceNet, a runtime assurance layer for deciding whether coordinated
agent operations have achieved an operator's network intent. Its broker collects the post-change observations required by a completion contract, and its admission gate checks that the evidence comes from the required scopes, remains current, and satisfies the task rules. A verifier
agent provides an additional assessment of the observation content. Experiments on live routing networks show that post-change state checks recognize successful outcomes that configuration-action records alone cannot establish. Controlled interventions further show that EvidenceNet rejects completion when otherwise satisfactory observations have the wrong source, have been substituted, or are stale.
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Systems and Control
Context operations to architecture modelling output from large language models and evaluation criteria for their use in systems engineering design
Vinicius Kaster Marini and Petter Krus
The development of generative artificial intelligence resources enables opportunities of speeding up systems and engineering design work. This contribution introduces a framework of formal operations for assembling context in LLM-based engineering design. This framework involves the assembly of modular context units, including policy
prompts, reference units with persistence, and user questions with
prompt vectoring. This approach enables the systematic structuring of interactions with generative models. A formal method for evaluating modelling-as-code LLM outputs is also presented, which enables the evaluation of compliance to intent from LLM answers and thereby asses the support from LLMs for systems architecture modelling.
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Systems and Control · Cross-listed from cs.CE
Joint nonlinearity in a stiffened aluminium wingbox panel and what it requires of a reduced basis
Nikolaos D. Tantaroudas and Evangelos Papatheou
A shell finite-element model of a stiffened aluminium wingbox panel, a laboratory structure shared by several experimental studies, is built with its plate-to-stiffener joints at the $78$ physical fastener positions and calibrated against measured modal data, a six-parameter sensitivity update of the substructure moduli within $\pm20\%$ reproducing the first five measured modes to $1.1$–$4.3\%$ with modal-assurance values of $0.88$–$1.00$. Making the fasteners nonlinear, at equal mesh, mass and damping, shows that joint nonlinearity enters the response strongly asymmetrically. Hardening is almost invisible, at most $+1\%$ in frequency, whereas softening or slipping the joints moves the first three resonances by $-2.1$, $-4.9$ and $-9.2\%$, and friction removes up to $80\%$ of the resonant peak before it recovers. Newmark integration of all $18{,}804$ degrees of freedom and a harmonic balance condensed exactly onto the joints and continued in arclength agree to $5.5\times10^{-4}$. A projection-based nonlinear model order reduction then locates the criterion that a jointed structure imposes on a reduced basis. The binding quantity is not the linear response, which eleven vectors reproduce to better than $0.01\%$, but the receptance of the structure between the joints, of which $126$ global eigenvectors carry about $2\%$, and without which the reduced model overpredicts the hardening shift of the fundamental by a factor of thirty and returns a value beyond the rigid-joint limit of the panel.
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Systems and Control · Cross-listed from cs.CV
Elastoformer: Enabling Dynamic Adaptivity via Elastic Model Transformation
Sudaksh Kalra and Dolly Sapra
EdgeAI systems are increasingly employing computer
vision applications to enable intelligent, on-device decision-making in real-time. However, these deployments face highly dynamic operational conditions, with fluctuating constraints on latency, power availability, and
memory resources. Deep Neural Networks (DNN), which follow fixed computational execution flows, lack the flexibility to adapt to such variability, resulting in inefficient and suboptimal performance in edge scenarios. This underscores the need for architectures that are not only efficient but also dynamically scalable at runtime. In this paper, we propose Elastoformer: A framework that transforms conventional neural networks (NN) into Elastic NN capable of real-time elastic inference. Unlike the conventional bag-of-models approach, which requires maintaining multiple independent models for different operating conditions, Elastoformer offers a single, modular solution that dynamically switches between multiple modes of operation at runtime, adapting efficiently to the changing computational budgets of edge devices without the overhead of managing separate models. Experiments reveal that our framework achieves up to 85% reduction in computation FLOPs, 50% reduction in latency and 76% reduction in
memory overhead, while showcasing the architecture agnostic nature of the framework across both
Vision Transformers and CNNs. Our code is available at https://github.com/sudaksh14/Elastoformer.
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Systems and Control
Review on State-of-the-art Energy Systems in the Arctic
Bilal Babar and Sabrina Sartori
The Arctic regions remain heavily dependent on fossil fuels for energy generation. At the same time, the Arctic is warming at a rate considerably faster than the global average, increasing the need for low-carbon and
climate-resilient energy systems. This review documents the current energy systems and assesses state-of-the-art energy solutions applicable to Arctic and cold-
climate regions, as well as the future direction of these emerging energy systems, and analyses the role of energy storage, heating requirements, and advanced energy solutions. A total of 88 research articles were systematically reviewed. The reviewed studies indicate the potential for wind and solar to reduce dependence on fossil-fuel based energy generation. For energy storage, the reviewed solutions include hydrogen for long-term storage, battery-based system for short-term storage and regulation, and thermal storage using boreholes to meet heating demand. Where a fully renewable system cannot provide the required reliability, diesel can serve as back up generation. Some barriers to widespread adoption are technological, such as the need for specialized planning tools and equipment resilient to harsh weather, and social and institutional, such as the need for governmental support, subsidies, and appropriate legal frameworks.
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Systems and Control · Cross-listed from math.OC
The Global Asymptotic Stability Problem for Linear MPC Is Undecidable
Johan Löfberg
We prove that deciding global asymptotic stability for constrained finite-horizon linear model predictive control is undecidable. This holds at horizon one with identity state, input, and terminal weights, unique optimizers, and global feasibility. Separate reductions cover predicted-state boxes, hard input boxes, and quadratically softened input boxes. A fourth reduction fixes the state and input dimensions to three and six. Hence undecidability is not caused by long horizons, growing dimensions, failures of recursive feasibility, or nonuniqueness.
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Systems and Control
Optimal Dispatch of a Hydrogen-Colocated Renewable-Powered Desalination Plant
Guochen Zhao and Ahmed S. Alahmed
This paper develops an analytical framework for profit-maximizing dispatch of water, electricity, and green hydrogen in a renewable-powered water desalination plant (WDP) combining thermal and reverse osmosis (RO) desalination. The optimal dispatch reveals that the schedules of the desalination units, electrolyzer, and grid interaction can all be characterized in closed form as functions of renewable generation. At low renewable output, the plant relies on thermal desalination and grid power while maintaining RO desalination and hydrogen production at their minimum setpoints. At high output, it reduces thermal desalination, increases RO desalination, and allocates surplus power and water to hydrogen production. For renewable output within a precomputed intermediate range, the WDP balances energy internally, allocating resources based on the relative marginal values of hydrogen and RO water. Simulations using real solar and plant data show that integrating RO and thermal desalination with renewable generation and hydrogen production achieves the highest daily profit of 75.945 k$, exceeding the best configuration without hydrogen by 15.1%.
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Systems and Control · Cross-listed from cs.NI
Can AI Agents Detect and Repair Artifact Drift in Network Experiments?
Tianzhu Zhang, Weichen Tao, Changgang Zheng et al. (+4 more)
In recent years, AI
agents have evolved into capable assistants that carry out multi-step tasks in digital environments. The network systems community is beginning to explore these capabilities in operational and experimental settings. However, an
agent operating in network systems should not be judged solely by whether it completes the immediate task. The experiment record it modifies must also remain trustworthy. We call this property artifact integrity: the record's claims must remain supported by the available evidence, confined to the scope established by that evidence, and traceable through the artifacts that encode their support. To make this property measurable, we introduce NetArtifactBench, which tests whether AI
agents can repair inconsistent records derived from public network-system artifacts while preserving claims that remain supported. The
benchmark contains 52 instances with injected inconsistencies ranging from direct contradictions to unstated relations spread across several artifacts. We evaluate 23
agent configurations across three general-purpose AI
agent runtimes using deterministic scoring. The average contract pass rate is 65.3 % across 5,980 outputs, but no
agent runtime exceeds 30 % when repair requires recovering implicit relations and propagating changes across artifacts. These results reveal a sharp boundary between local correction and complete record-level repair. Therefore, we argue that artifact integrity should become a first-class design and evaluation requirement for AI
agents operating on network systems.
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All authors Tianzhu Zhang, Weichen Tao, Changgang Zheng, Yusheng Zheng, Long Chen, Xiaoyi Fan, Meikang Qiu
Systems and Control
Semi-Cooperative Passive Integrated Sensing and Communication by Utilizing Physical Layer Information of 5G Signals
Bo Wei, Ryusei Ogane and Hang Song
In recent years, integrated sensing and communication (
ISAC) has attracted significant
attention towards future cellular networks. Currently, various works have demonstrated sensing performance in existing wireless communication systems. Most of the demonstrations are based on passive type due to the
radio regulatory. However, because of the difficulty in access to the communication protocol stacks in commercial cellular systems, the evaluation of the cellular communication signals for semi-cooperative passive
ISAC is limited. In this paper, a semi-cooperative passive
ISAC system is developed with open-source 5G framework and software-defined
radio devices. And the performance is experimentally evaluated by utilizing the physical layer information of actual 5G signals from the developed system. In this system, communication is established with 5G signals and physical layer information are obtained and extracted for analysis. The performance of the system is verified by conducting experiments under several communication scenarios including the synchronization, pinging, and data transmission. Different physical layer information is collected, and the propagation characteristics are analyzed by a multi-path configuration. The experiment results demonstrated that variable bandwidths were utilized for different communication scenarios and the multipath was successfully detected with two different approaches. These results show that the developed system is promising for semi-cooperative passive
ISAC in wider application fields
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Systems and Control
Entropy-Regularized Optimal Transport for Time-Varying Multi-Agent Coverage Control
Italo Napolitano and Mario di Bernardo
This paper addresses time-varying coverage control for multi-
agent systems, formulated as the tracking of an evolving target density via
entropy-regularized semi-discrete optimal transport. Unlike the hard Laguerre partition of the unregularized formulation, entropic regularization assigns fractions of the mass at each point to all
agents, simplifying the design and numerical implementation of the control law. We derive a feedback-feedforward controller that tracks the evolving first-order optimality conditions with exponential convergence, and we investigate the role of the regularization parameter, which, above a critical threshold, renders the fully collapsed configuration locally optimal. Numerical experiments validate the theory: for moderate regularization, the proposed approach has performance comparable to the unregularized formulation and outperforms the corresponding Voronoi-based coverage baseline.
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Systems and Control
Spatial LLM Workload Shifting Needs Foresight: Model Commitment for AI Data Center Operation under Power Grid Constraints
Bojun Du, Hongyang Jia, Tonghui Li et al. (+4 more)
AI data centers may face power supply shortages during certain periods, requiring operators to shift large
language model (LLM) inference workloads spatially to maintain service rates. However, existing workload-shifting methods typically assume that any data center with sufficient computing resources can immediately serve shifted requests, which may lead to infeasible transfers and unserved demand. This letter proposes model commitment (MC), a mixed-integer linear programming framework that jointly schedules model deployment and cross-site request routing under power constraints and electricity-price signals. First, MC formulates the intertemporal coupling introduced by model replica loading. Second, it translates prefill and decode latency requirements into the amount of demand that each replica can serve. Case studies based on real-world data show that MC enables AI data center operators to achieve a 100% service rate under time-varying grid conditions and reduce total operating cost by 29.0%.
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All authors Bojun Du, Hongyang Jia, Tonghui Li, Qingchun Hou, Ze Wang, Ershun Du, Ning Zhang
Systems and Control
Graph-Based Characterization of Vision-Derived Dynamic Modes for Structural Damage Identification
R K B M Rizmi, Khalid Mahmud Labib and Shabbir Ahmed
This study presents a graph theoretic framework for characterizing damage-induced changes in the dynamics of a vibrating cantilever beam from non-contact
video measurements. Within this approach, dynamics of the beam under healthy and damaged conditions with crack depths of 5, 10, and 13 mm are initially modeled using delay-embedded dynamic mode decomposition (DMD) from
vision-based measurements. The resulting mode
matrix from DMD is used to construct the adjacency
matrix of a graph for this vibrating beam system, and its topological features such as graph connectivity, centrality, two-
star statistics, and dyadic configurations are evaluated as damage-sensitive measures. Additionally, different DMD-based spectral and modal measures are evaluated to support the graph theoretic damage assessment. The results show a monotonic reduction in graph connectivity, nodal accessibility, and local organization of the graph with increasing crack depth. A parametric numerical study further validates the decreasing connectivity trend observed experimentally. The results demonstrate that the topological features of the graph derived from the DMD mode
matrix provide an interpretable representation of damage-induced changes in the beam dynamics and offer a promising basis for
vision-based structural damage identification.
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Systems and Control
Koopman Spectral Reduced-Order Modeling of Spherical Diffusion in Lithium-Ion Batteries
Jihoon Moon
Physics-based battery models provide internal electrochemical states for estimation and control, but solving the partial differential equations governing solid
diffusion can be computationally expensive. This paper therefore develops an analytical Koopman spectral reduced-order model for the single particle model. The Koopman eigenfunctionals and
eigenvalues are derived directly from the eigenfunctions of the self-adjoint zero-flux
diffusion operator. The zero mode represents the volume average concentration, the nonzero modes describe decaying radial gradients, and projection of the current dependent surface flux yields a linear state-space model that reconstructs the average, surface, and full radial concentrations. Unlike data-driven Koopman models, the proposed formulation requires neither training data nor empirical lifting functions. Compared with a 400 control volume finite volume model (FVM) during a constant 1C discharge, the 80 Koopman mode model achieves negative and positive surface concentration RMSE values of $1.26\times10^{-5}\,\mathrm{mol/m^{3}}$ and $4.10\times10^{-6}\,\mathrm{mol/m^{3}}$, a terminal voltage RMSE of $8.42\times10^{-4}\,\mathrm{V}$. The models with 5 and 80 Koopman modes were approximately 225 and 31 times faster than the FVM model, respectively. These results demonstrate a physically interpretable and computationally efficient representation of battery
diffusion dynamics.
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