Systems and Control · Cross-listed from cs.AI
FORGE: Self-Evolving Agent Memory With No Weight Updates via Population Broadcast
Igor Bogdanov, Chung-Horng Lung, Thomas Kunz et al. (+3 more)
Can LLM
agents improve decision-making through self-generated
memory without gradient updates? We propose FORGE (Failure-Optimized Reflective Graduation and
Evolution), a staged, population-based protocol that evolves
prompt-injected natural-
language memory for hierarchical ReAct
agents. FORGE wraps a Reflexion-style inner loop, where a dedicated reflection
agent (using the same underlying LLM, no
distillation from a stronger model) converts failed trajectories into reusable knowledge artifacts: textual heuristics (Rules), few-shot demonstrations (Examples), or both (Mixed), with an outer loop that propagates the best-performing instance's
memory to the population between stages and freezes converged instances via a graduation criterion. We evaluate on CybORG CAGE-2, a
stochastic network-defense POMDP at a 30-step horizon against the B-line attacker, where all four tested LLM families (Gemini-2.5-Flash-Lite, Grok-4-Fast, Llama-4-Maverick, Qwen3-235B) exhibit strongly negative, heavy-tailed zero-shot rewards. Compared against both a zero-shot baseline and a Reflexion baseline (isolated single-stream learning), FORGE improves average evaluation return by 1.7-7.7$\times$ over zero-shot and by 29-72% over Reflexion in all 12 model-representation conditions, reducing major-failure rates (below $-100$) to as low as $\sim$1%. We find that (1) population broadcast is critical mechanism, with a no-graduation ablation confirming that broadcast carries the performance gains while graduation primarily saves compute; (2) Examples achieves the strongest returns for three of four models, Rules offers the best cost-reliability profile with $\sim$40% fewer
tokens; and (3) weaker baseline models benefit disproportionately, suggesting FORGE may mitigate capability gaps rather than amplify strong models. All evidence is confined to CAGE-2 B-line; cross-family findings are directional evidence.
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All authors Igor Bogdanov, Chung-Horng Lung, Thomas Kunz, Jie Gao, Adrian Taylor, Marzia Zaman
Systems and Control · Cross-listed from cs.CL
A Unified Generative-AI Framework for Smart Energy Infrastructure: Intelligent Gas Distribution, Utility Billing, Carbon Analytics, and Quantum-Inspired Optimisation
Pavan Manjunath and Thomas pruefer
The accelerating convergence of smart metering, generative artificial intelligence, and
quantum-inspired combinatorial optimisation is reshaping how energy utilities manage physical infrastructure, customer engagement, and environmental accountability
Systems and Control · Cross-listed from cs.IT
Preemption Revisited: Multi-Threshold Preemption Policies for AoI Minimization
Sahan Liyanaarachchi, Sennur Ulukus and Nail Akar
The study of optimal preemption policies for status update systems has been a recurring topic in the age of information (AoI) literature, where threshold-based structures have been shown to be optimal under a generate-at-will update generation model under certain assumptions. In this work, we study the effectiveness of threshold-based policies for a system with random update arrivals. In this regard, we introduce an analytical framework for evaluating the AoI of multi-threshold preemption policies and present interesting characteristics of the structure of the optimal preemption policy. We show the effectiveness of these threshold-based policies over the traditional probabilistic preemption policies and single-threshold policies, where we observe that significant gains in terms of AoI can be obtained by utilizing both the age of the packet and the age of the system when designing these preemption policies.
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Systems and Control · Cross-listed from cs.AI
Context, Reasoning, and Hierarchy: A Cost-Performance Study of Compound LLM Agent Design in an Adversarial POMDP
Igor Bogdanov, Chung-Horng Lung, Thomas Kunz et al. (+3 more)
Deploying compound LLM
agents in
adversarial, partially observable sequential environments requires navigating several design dimensions: (1) what the
agent sees, (2) how it reasons, and (3) how tasks are decomposed across components. Yet practitioners lack guidance on which design choices improve performance versus merely increase inference costs. We present a controlled study of compound LLM
agent design in CybORG CAGE-2, a cyber defense environment modeled as a Partially Observable Markov Decision Process (POMDP). Reward is non-positive, so all configurations operate in a failure-mitigation mode. Our evaluation spans five model families, six models, and twelve configurations (3,475 episodes) with
token-level cost accounting. We vary context representation (raw observations vs. a deterministic state-tracking layer with compressed history), deliberation (self-questioning, self-critique, and self-improvement tools, with optional chain-of-thought prompting), and hierarchical decomposition (monolithic ReAct vs. delegation to specialized sub-
agents). We find that: (1) Programmatic state abstraction delivers the largest returns per
token spent (RPTS), improving mean return by up to 76% over raw observations. (2) Distributing deliberation tools across a hierarchy degrades performance relative to hierarchy alone for all five model families, reaching up to 3.4$\times$ worse mean return while using 1.8-2.7$\times$ more
tokens. We call this destructive pattern a deliberation cascade. (3) Hierarchical decomposition without deliberation achieves the best absolute performance for most models, and context engineering is generally more cost-effective than deliberation. These findings suggest a design principle for structured
adversarial POMDPs: invest in programmatic infrastructure and clean task decomposition rather than deeper per-
agent reasoning, as these strategies can interfere when combined.
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All authors Igor Bogdanov, Chung-Horng Lung, Thomas Kunz, Jie Gao, Adrian Taylor, Marzia Zaman
Systems and Control
Watts vs. Bytes: Turning Data Centers into Grid Assets via Storage Compute Co-Optimization
Shaohui Liu, Sungho Shin and Deepjyoti Deka
Data center interconnections increasingly face tighter peak-demand and ramp-rate limits while being expected to support grid operations. Satisfying these requirements calls for coordinated computing and energy controls, yet their joint operational and economic implications remain poorly understood. To tackle this problem, we formulate a robust day-ahead co-optimization of computing load scheduling, server dynamic voltage and frequency scaling (DVFS), and co-located battery energy storage system (BESS) dispatch. The resulting mixed-integer linear program hedges against uncertainty in fixed load and ancillary service deployment while enforcing interconnection limits on peak demand and ramp rate, ancillary service capacity commitments in reserve and flexible ramping, and workload execution constraints. Case studies using CAISO and PJM
market data of a 100~MW data center with a 36~MWh/12~MW BESS show that workload scheduling, DVFS, and storage provide complementary flexibility. Under binding peak-load limits, increasing the schedulable workload share reduces mean daily operating cost by up to 20.7%, and the daily value of storage more than doubles relative to operation under less restrictive limits. Under normal conditions, optimal BESS sizing is driven more by capital cost and cycling allowance than by energy duration alone. An 8~MW aggregate ancillary service commitment increases operational cost by only 0.4%, whereas reserve-only requirements become infeasible at commitments as small as 4~MW. These findings show that coordinated computing and storage controls can support grid services economically under binding interconnection constraints while protecting workload delivery.
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Signal Processing · Cross-listed from cs.IT
How Far Back in Time a Digital Twin Reflects the State of the Physical Object: Age of Staleness
Ismail Cosandal and Sennur Ulukus
The groundbreaking metric age of information (AoI) has been introduced to measure information freshness in communication networks. As transformational as it is, AoI metric falls short in some applications, such as remote monitoring, since it is a semantic-agnostic metric which does not consider the dynamics of the random process. There is a need to quantify the performance of a remote
estimator via a metric that combines freshness and semantic aspects. To this end, in this paper, we introduce a novel metric coined age of staleness (AoS) that measures when the last time that the current estimation was correct. First, we analyze a simple scenario where an $n$-ary symmetric Markov source is observed by a monitor via a constant sampling rate, obtain a closed-form expression for the AoS, and show that it is a monotonically decreasing function of the sampling rate. Next, we consider multiple distinct Markov sources, and formulate an optimization problem, where the remote monitor allocates the total sampling rate to tracking the sources. Although the optimization problem is non-convex, its structure is suitable for obtaining a near-optimal solution using the polyblock
algorithm, which leverages the monotonicity of the objective function. While the new AoS metric could be applicable in many scenarios, we believe it is particularly well-suited for a digital twin network (DTN) where multiple physical objects (POs) are monitored with a total sampling rate constraint to maintain a digital representation of them, namely, their digital twin (DT).
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Signal Processing
MAxLM: Multi-Agent Language Model-Based Scheduling and Resource Allocation in MU-MIMO-OFDMA-Enabled Wireless Networks
Adnan Quadri and Hongxiang Li
Wireless networks support multi-user (MU) communication with multiple-input multiple-output (
MIMO) and orthogonal frequency-division multiple access (OFDMA) technologies. In the joint MU-
MIMO-OFDMA-enabled transmission mode, network throughput can be significantly increased by effectively utilizing the multi-channel resources to schedule numerous wireless users/stations (STAs) simultaneously. In this paper, we study ways to optimize the user scheduling and resource allocation (SRA) for the UL scheduled access (UL-SA) of a joint MU-
MIMO-OFDMA-enabled wireless local area network (WLAN). In particular, we propose a multi-
agent (MA) framework that utilizes an openly available pretrained small/medium-sized
Language Model (xLM) to perform SRA for the UL-SA. To facilitate autonomous SRA using our proposed technique, we introduce the AI-assisted Wireless Systems Engineering and Research (WiSER) platform. We evaluate the performance of MAxLM-optimized SRA for network scenarios with a varying number of STAs and
antenna settings on the WLAN Access Point. Numerical results confirm that our proposed technique achieves higher UL-SA throughput than the
benchmark techniques.
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Signal Processing
SiFo: Wireless Foundation Model for Low-Overhead Site-Specific CSI Feedback
Cheng-Jie Zhao, Zhaolin Wang, Zongyao Zhao et al. (+1 more)
SiFo, a wireless foundation model-based framework, is proposed for low-overhead site-specific channel state information (CSI) feedback. In 3GPP NR, Type-II feedback provides an expressive codebook-based CSI representation, but it requires substantial reference-signal overhead, UE-side search, and feedback. Learning-based site-specific feedback can reduce these online costs while retaining high-quality subspace representation by exploiting deployment-dependent propagation structure. However, existing site-specific designs typically train a dedicated neural network for each new site, which limits scalability when the number of deployments is large. SiFo addresses this scalability issue by pretraining a CSI feedback model across source sites and adapting it to a target site through lightweight calibration. A small set of target-site users reports low-dimensional reference signal received power (RSRP) fingerprints, and their full-CSI-based subspace labels are stored as calibration
memory. During online operation, a served user is matched to calibrated users through the same SSB probing and RSRP reporting procedure, so nearby calibration samples provide site-specific subspace guidance without updating model parameters. SiFo therefore transfers common propagation knowledge while retaining local adaptation. Numerical results across ten city scenarios demonstrate that SiFo (i) achieves higher CSI-capture efficiency than separately trained site-specific learning baselines under the same target-site labeled budget, (ii) approaches the high-overhead 3GPP NR Type-II feedback reference using only RSRP measurements collected during online SSB probing, and (iii) converts the high CSI-capture efficiency and low overhead into effective spectral efficiency improvement under limited target-site data.
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All authors Cheng-Jie Zhao, Zhaolin Wang, Zongyao Zhao, Yuanwei Liu
Systems and Control · Cross-listed from cs.IT
Covert Bayesian Quickest Change Detection
Yun-Feng Lo and Matthieu R. Bloch
We investigate the problem of covert quickest change detection in a
Bayesian and infinite-horizon setting. A legitimate entity seeks to detect a change in the state of a discrete memoryless channel as quickly as possible by actively probing it. Simultaneously, the entity must ensure its probing remains covert from an adversary monitoring the channel for active sensing. We introduce the expected covertness budget (ECB) as an analytically tractable covertness metric that bounds from above the relative
entropy between the observation sequences induced by active and passive sensing. Under constraints on both the probability of false alarm (PFA) and the ECB, we establish a second-order asymptotic converse bound on the average detection delay as the PFA constraint approaches zero, for any positive ECB constraint, explicitly quantifying the maximum square-root-order covert sensing gain possible. Furthermore, we propose an achievability scheme utilizing a constant-sensing-probability Shiryaev-type policy and show that it matches the second-order asymptotic converse. We illustrate our result with a numerical example.
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Signal Processing · Cross-listed from cs.IT
GeoGS-CE: Learning Delay–Beam Channel Priors with 3D Gaussians for High-Mobility Scenarios
Yumeng Zhang, Jiajia Guo, Chaozheng Wen et al. (+2 more)
Wideband channel estimation (CE) in high-mobility scenarios remains challenging because channel responses vary rapidly, while practical systems can allocate only sparse pilots to accommodate dense users. Fortunately, many high-mobility environments, such as high-speed railways, exhibit scheduled trajectories, predictable velocities, and a limited number of dominant propagation paths. These properties induce a delay–beam power spectrum that is more stable than the instantaneous complex channel frequency response (CFR), less sensitive to the random phase coherence, and rich in
geometric information. To exploit such environmental properties, we propose GeoGS-CE, a two-stage channel estimation framework for sparse-pilot high-mobility scenarios. In the offline stage, GeoGS-CE jointly models: 1) a scene-level 3D Gaussian representation that captures the non-line-of-sight (NLoS)
geometric scattering support, and 2) a leakage-aware differentiable wireless rendering process that maps the NLoS Gaussians, together with an explicit virtual line-of-sight (LoS) component, to the measured delay–beam power spectrum, while accounting for practical OFDM delay and array leakage effects. In the online stage, the delay–beam power spectrum is predicted for each user location and used as a strong covariance prior, enabling accurate full-band and full-array CFR reconstruction and tracking through a linear MMSE
estimator. Simulations based on channels generated from a segment of the Guangshen high-speed railway show that the proposed
geometric prior substantially improves CFR reconstruction over pilot-only and non-
geometric baselines.
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All authors Yumeng Zhang, Jiajia Guo, Chaozheng Wen, Chenghong Bian, Jun Zhang
Systems and Control
Active Learning MPC Objective Functions from Preferences
Hasna El Hasnaouy, Pablo Krupa, Mario Zanon et al. (+1 more)
Designing the objective function in Model Predictive Control (MPC) is challenging when performance assessment criteria are available only from human judgment. We adopt a preference-based learning (PbL) approach to learn the MPC objective function from preferences over trajectory pairs. However, the real-world application of PbL is often restricted by the significant cost or limited availability of human preference queries. To address this, Active Learning (AL) strategies seek to improve sampling efficiency, reducing the labeling effort required to obtain a well-performing classifier. We present two AL strategies for learning the MPC objective function from human preferences over pairwise system trajectories: a pool-based strategy that selects trajectory pairs that are both uncertain under the current surrogate and diverse relative to previously labeled comparisons, and a query-synthesis strategy that incorporates new trajectories using the current surrogate-driven MPC. Numerical results show that the proposed strategies yield closed-loop behaviors that align more with the expressed preference using fewer number of queries compared to a random sampling approach.
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All authors Hasna El Hasnaouy, Pablo Krupa, Mario Zanon, Alberto Bemporad
Signal Processing
Holographic Airy Beamforming: Curved Trajectory Optimization for Blockage-Resilient Terahertz Communications
Xinyuan Hu, Boya Di and Lingyang Song
Terahertz communication offers vast bandwidth for high-speed transmission in the 6G networks but faces severe blockage challenges in the near-field region due to large
antenna arrays. To overcome the limitation that near-field focused beams are susceptible to obstacles, wavefront engineering is leveraged to generate an Airy beam that propagates along a
parabolic trajectory to circumvent blockages. In this paper, we consider the reconfigurable
holographic surface (RHS) as a potential solution for such precise wavefront engineering owing to its compact radiation element spacing being much smaller than half-wavelength. We reveal that the adjustable effective aperture of the RHS allows the
parabolic offset to be located within the
antenna aperture, which enhances the freedom in designing Airy beam trajectories. An analog beamforming method, named the
holographic Airy beamforming scheme based on amplitude control, is then proposed to generate the curved beam that propagates along the desired trajectory. To maximize the received power of a blocked user, we develop a geometry-based trajectory optimization
algorithm. Simulation results validate that, compared to traditional phase-controlled arrays with analog beamforming, the RHS can leverage its adjustable effective aperture to improve the received power of the blocked user by over 10 dB.
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Systems and Control
OCO-S$^2$: Online Convex Optimization with Stateful Costs and Sparse Communication
Yiwei Liu, Luwei Yang and Shunbo Lei
We study \textsc{OCO-S$^2$}, an online convex optimization setting in which decisions drive a stable dynamical state, losses are incurred along the induced state trajectory, and first-order feedback is available only through sparse block communication with partial participation. This coupling creates a dynamic-regret problem beyond pointwise OCO: the learner updates and holds decisions at the block scale, whereas the hindsight comparator may vary at the per-round scale. We propose \textsc{OCO-S$^2$-OGD}, a projected block online gradient method that updates deployed decisions using sparse block-level distributed feedback. We prove dynamic-regret bounds for the incurred trajectory cost, quantifying the tradeoff among block communication, comparator variation, state-
memory truncation, and partial participation. We further introduce a prediction-augmented variant, \textsc{OCO-S$^2$-OGD-P}, and show that accurate block-level predictions improve the optimization term in the regret bound through their realized gradient-mismatch error. Overall, this work provides a regret-theoretic foundation for communication-efficient online decision-making in systems where algorithmic updates and physical state trajectories are intrinsically coupled.
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Signal Processing
Enhanced input stacking for non-square MIMO modal identification of aeronautical structures via Fast and Relaxed Vector Fitting
Beatrice E. Bauret Martínez, Gabriele Dessena, Marco Civera et al. (+1 more)
Fast and Relaxed Vector Fitting (FRVF) is a frequency-domain system identification approach that has been widely adopted in electrical system modelling, while its application to mechanical systems has remained relatively unexplored. In this work, FRVF is reformulated for the identification of structural modal parameters of an aircraft based on Ground Vibration Test (GVT) data within a Multi-Input Multi-Output (
MIMO) framework. The proposed procedure consists of three stages: (i) rational approximation of frequency response functions via an enhanced input-stacking strategy, (ii) identification of system poles from the resulting rational model, and (iii) estimation of modal parameters from the extracted poles and associated residues. The methodology is first numerically validated on a
MIMO beam model, with particular emphasis on accuracy and robustness under increasing measurement noise. Subsequently, experimental validation is conducted using GVT data from the BAE Systems Hawk T1A aircraft. The results obtained demonstrate a level of performance comparable to that achieved by existing methods. Overall, the extended
MIMO formulation of FRVF exhibits high accuracy and strong robustness to measurement noise, highlighting its suitability for application in GVT-based modal analysis.
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All authors Beatrice E. Bauret Martínez, Gabriele Dessena, Marco Civera, Oscar E. Bonilla-Manrique
Signal Processing
Reciprocal Beyond Diagonal Reconfigurable Intelligent Surface: Distributed Scattering Matrix Design and MIMO Beamforming via Fractional Programming and Manifold Optimization
Iván Alexander Morales Sandoval, Marko Fidanovski, Hyeon Seok Rou et al. (+2 more)
We consider the optimization of beyond diagonal reconfigurable intelligent surface (BD-RIS)-aided multi-user (MU)
cell-free (CF)-massive multiple-input multiple-output (mMIMO) systems, where the propagation environment design achieved scattering
matrix optimization is complemented by developing an efficient base station (BS) beamforming (BF) scheme that effectively exploits the latter “engineered” channel. In particular, we describe a fractional programming (FP) method, which based on the equivalent channel incorporating a reciprocal BD-RIS (RBD-RIS) parameterized by existing scattering
matrix design methods, yielding the correspondingly optimized multiple-input multiple-output (
MIMO) BF weights. The proposed approach decomposes the transmit (TX) beamformer into multiple sum-rate maximization (SRM) sub-beamformers, each satisfying an independent power-constraint, such that distributed
MIMO-BF scenarios can be optimally handled. Although the proposed SRM-
MIMO-BF framework is independent of the specific scattering
matrix design, extending the BD-RIS-aided system model to the CF-mMIMO setting requires the design of a corresponding beamforming
matrix. In this context, this work investigates the impact of beamforming in reconfigurable intelligent surface (RIS)-aided systems. Simulation results demonstrate that the proposed method for designing the
MIMO-BF weights, when combined with the previously developed design of reciprocal BD-RIS (RBD-RIS) scattering
matrices, outperforms existing BD-RIS-aided state-of-the-art (SotA) schemes employing existing
MIMO-BF techniques, indicating that the whole contribution is more than the sum of the parts.
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All authors Iván Alexander Morales Sandoval, Marko Fidanovski, Hyeon Seok Rou, Giuseppe Thadeu Freitas de Abreu, Emil Björnson
Systems and Control · Cross-listed from cs.RO
Constrained MPC-Based Motion Planning for Morphing Quadrotors in Ultra-Narrow Passages under Limited Perception
Harsh Modi, Xiao Liang and Minghui Zheng
This paper introduces a motion planning framework to plan morphology and trajectory for morphing quadrotors under extremely constrained environments. We develop a novel obstacle avoidance cost function for nonlinear model predictive control (MPC) that enables
navigation through extremely narrow gaps under limited perception from a 2D
LiDAR. Classical artificial potential field-based costs typically have a high cost in narrow passages, artificially blocking the navigable path. In contrast, we propose a smooth exponential obstacle cost that preserves low traversal cost within narrow gaps while maintaining strong collision avoidance behavior. The formulation avoids hard activation thresholds and introduces a cost reduction factor to reduce the cost within narrow passages. Direct use of 2D
LiDAR measurements in MPC allows
navigation around arbitrarily shaped obstacles. The method is embedded within an acados-based nonlinear MPC framework. Simulation and experimental results demonstrate successful traversal of narrow corridors where typical repulsive cost functions would fail. The approach provides a computationally efficient and practical solution for navigating through tight spaces while maintaining safety from the obstacles. While we are implementing the framework on the morphing quadrotors, the cost function formulation is general-purpose for any mobile
robot application, and is not limited to the morphing quadrotors. The implementation code is available at \href{https://github.com/harshjmodi1996/morphocopter_mpc}{Github Repo} and a short
video is available at \href{https://zh.engr.tamu.edu/wp-content/uploads/sites/310/2026/03/MPC_MorphoCopter_
video.mp4}{
Video Link}.
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Signal Processing
Topological Kalman Filtering on Cell Complexes
Chengen Liu, Rohan Money, Ting Gao et al. (+3 more)
Inferring latent dynamics from multivariate time-series defined over topological
cell complexes is crucial for capturing the complex, higher-order interactions inherent in real-world systems such as in water, sensor, and transportation networks. However, reconstructing these latent states is challenging because the signals are coupled across higher-order
topologies, while high dimensionality, nonlinear observations, and unknown structures increase the difficulty. To address this, we propose a
topology-aware state space framework derived from
stochastic partial differential equations on
cell complexes. State
evolution follows heat-like topological
diffusion, with perturbations propagating along boundary operators. Under partial observability, we model observations using a
cell complex convolution of latent states coupled with a nonlinear mapping. We perform recursive state estimation via an Extended Kalman Filter, simultaneously learning model parameters and uncertainties through an online Expectation-Maximization
algorithm. Finally, for scenarios where only lower-order topological structure is known, e.g., nodes and edges, as in critical infrastructure networks, we introduce a heuristic
cell identification
algorithm to explicitly infer the second-order
cell structures. Validations on synthetic and real
datasets from water, sensor and transportation networks demonstrate that our approach yields reliable estimates under partial observability and successfully recovers the underlying topological structures.
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All authors Chengen Liu, Rohan Money, Ting Gao, Mohammad Sabbaqi, Baltasar Beferull-Lozano, Elvin Isufi
Signal Processing
Robust Beamforming for Near-Field STAR-RIS-Enabled ISCPT
Zahra Rostamikafaki, Francois Chan and Claude D'Amours
A simultaneously transmitting and reflecting reconfigurable intelligent surface (
STAR-RIS)-aided near-field integrated sensing, communication, and power transfer (ISCPT) framework is proposed. We formulate a robust harvested power maximization problem under imperfect cascaded channel state information (CSI), with constraints on required user rate, eavesdropper tolerable rate, and minimum sensing beampattern gain. To address this non-convex problem, we adopt alternating optimization (AO). First, we approximate the semi-infinite inequality constraints using the S-procedure and obtain rank-one active beamforming via sequential rank-one constraint relaxation (SROCR); then we update the passive
STAR-RIS coefficients with a penalty-based scheme refined by successive convex approximation (SCA). Simulations in the near field demonstrate notable gains in harvested power while meeting secrecy and beampattern targets, outperforming conventional baselines.
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Systems and Control
State Estimation
Hao Li
Control science is a core representative of the third industrial revolution and is so important to modern civilization. Control systems are the main subject of control science and may involve many aspects of consideration, such as hardware consideration, software consideration, operation consideration, maintenance consideration, economy consideration, society consideration. However, besides all such aspects of consideration, one aspect that is most essential to the control system is methodology consideration in mathematical sense, knowledge on which is what we refer to as control theory. Besides its importance from the mathematical perspective, control theory is even more charming as it is deeply rooted in practical applications. Charms of control theory consist in both know-why and know-how and it is the fusion of control theory and practical applications that highlights such charms. Control theory for practical applications, especially when somewhat with so-called "advanced" flavour, involves several fundamental aspects. This article introduces the State Estimation aspect of Advanced Control Theory for Practical Applications [1,2].
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Systems and Control · Cross-listed from cs.RO
Dynamic Plasma Shape Control with Arbitrary Sensor Subsets
D. Sorokin, M. Stokolesov, A. Granovskiy et al. (+7 more)
Plasma shape control in tokamaks requires a real-time controller that tracks dynamically changing shape targets while tolerating diagnostic failures. Classical approaches decompose the problem into
equilibrium reconstruction followed by a linear controller, and assume a fixed, fully operational sensor set. We present a reinforcement learning
agent that addresses both limitations simultaneously. The
agent is trained in NSFsim, a high-fidelity tokamak simulator configured for DIII-D, on a curated
dataset of 120 experimental
plasma shapes. The shape targets are resampled as random step changes every 0.25 s, exposing the
agent to diverse transitions across the full shape envelope. At test time the
agent zero-shot tracks dynamic shape sequences; on a held-out static configuration in simulation it achieves a mean shape error of 2.01 cm, and dynamic trajectory following is demonstrated qualitatively in simulation and on the physical device. Diagnostic dropout randomly masks 30% of
magnetic sensors per episode, yielding a single policy robust to arbitrary sensor subsets without backup controllers or mode-switching logic. An asymmetric actor-critic architecture with privileged
equilibrium information improves value estimation under partial observability; an auxiliary shape reconstruction head on the actor enables end-to-end shape reconstruction from raw diagnostics and serves as an interpretability tool for policy analysis. The policy transfers to experimental DIII-D shots, where it directly commands the coil actuators on two dynamic shape maneuvers, and to the independent GSevolve simulator.
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All authors D. Sorokin, M. Stokolesov, A. Granovskiy, I. Prokofyev, E. Adishchev, M. Nurgaliev, E. Khayrutdinov, G. Subbotin, R. Clark, D. Orlov
Image and Video Processing
Layer Selection in Feature-Based Losses Affects Image Quality and Microstructural Consistency in Deep Learning Super-Resolution of Brain Diffusion MRI
David Lohr and Rene Werner
Clinical application of high-resolution
diffusion MRI is hindered by hardware limitations and prohibitive scan times, motivating computational super-resolution. This study investigates the efficacy of a feature-based loss function in preserving
diffusion signal consistency in deep learning super-resolution. Using 7T data from the human connectome project to generate pairs of low- and high-resolution
diffusion weighted images (DWI), we trained UNets for 2D super-resolution. Ablation and isolation studies evaluated different VGG16-layers for feature-based losses against an image-based L1 baseline. Deeper layers and combinations thereof resulted in grid-like artifacts in super-resolution DWIs, which persisted in
diffusion parameters like quantitative and fractional anisotropy. No such artifacts were present when using the shallowest layer. Downstream analysis for this layer showed great consistency with the ground truth, even for 9-fold super-resolution. Image SNR and used VGG16-layer depths modulated artifact appearance and severity, mandating careful selection of contributing layers for application in and beyond
diffusion MRI.
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Systems and Control
Communication-Efficient Approximate Gradient Coding for Distributed Learning in Heterogeneous Systems
Heekang Song and Wan Choi
We propose a communication-efficient optimally structured gradient coding scheme to jointly address straggler resilience and communication efficiency in heterogeneous distributed learning. By establishing a unified framework that simultaneously optimizes gradient coding and quantization, we formulate an optimization problem to minimize residual error subject to an unbiasedness constraint. We rigorously establish the joint global optimum by deriving a closed-form code structure coupled with an optimal bit allocation strategy, while simultaneously proposing a low-complexity bit allocation
algorithm that efficiently yields near-optimal performance. We provide rigorous convergence analysis for convex and smooth functions. Experiments on the COCO
dataset demonstrate that our joint design significantly accelerates convergence and enhances communication efficiency compared to existing baselines.
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Signal Processing
Agent-Native Wireless Communications: Architecture, Opportunities, and the Road Ahead
Yuanwei Liu, Xu Gan, Zhaolin Wang et al. (+3 more)
Future wireless networks are moving toward autonomous service operation, where network control and resource management need to respond to time-varying
radio conditions and evolving service objectives. To address this shift, this article develops an
agent-native wireless communication framework that characterizes the interplay between
agent intelligence and communication systems. In this framework, the coupling is organized around
agents for communications and communications for
agents. For
agent-native operation, the architecture is organized around deployable computing infrastructure, programmable open
radio access network (O-RAN) software, and controllable communication interfaces. Based on this architecture,
agents for communications addresses the use of
agents in communication-system design and operation, including
agent-generated communication software and
agent-driven adaptive wireless optimization. On the other side, communications for
agents addresses wireless service support for
agent operation, including network-supported single-
agent loops and network-assisted multi-
agent coordination. Finally, it outlines promising research directions for measurable, safe, and interoperable deployment of
agent-native wireless communications.
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All authors Yuanwei Liu, Xu Gan, Zhaolin Wang, Shan Shan, Zongyao Zhao, Zhiguo Ding
Audio and Speech Processing
Improving Automatic Speech Recognition for Speakers Treated for Oral Cancer using Data Augmentation and LLM Error Correction
Hidde Folkertsma, Thomas Tienkamp, Sebastiaan de Visscher et al. (+4 more)
In recent years, the performance of automatic
speech recognition (ASR) systems has made considerable progress. Unfortunately, for people with
speech impairments, such as people treated for oral cancer (OC), ASR performance is still lagging behind. The scarcity and variability of OC
speech data makes development of ASR models for this type of
speech difficult. In this work, we use data augmentation and large
language model (LLM) error correction to mitigate this problem. We apply various augmentation techniques on a corpus of Dutch oral cancer
speech to create synthetic data, and evaluate their effect on ASR performance. We finetune Whisper and Massively
Multilingual Speech (MMS) models for each augmentation technique and observe, on average, an 8% relative decrease in Word Error Rate (WER) when including data created using text-to-
speech (TTS). When employing LLMs for error correction, we see a further 21.4-26.2% relative decrease in WER for finetuned ASR models and a 10.0% relative decrease for non-finetuned models. Overall, we achieve a 40% relative WER decrease for Whisper and a 50% relative WER decrease for MMS, indicating that a combination of data augmentation and LLM correction is a viable strategy for the recognition of OC
speech.
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All authors Hidde Folkertsma, Thomas Tienkamp, Sebastiaan de Visscher, Max Witjes, Rob van Son, Jiapan Guo, Bence Mark Halpern
Systems and Control
Uncertainty Propagation under Residual Disturbances: A Smart-Home Case Study
Guanru Pan, Dirk Reinhardt, Sebastien Gros et al. (+1 more)
This paper presents a data-driven framework for uncertainty propagation under unmeasured or statistically unmodeled (unstructured) disturbances. We consider residual disturbances, which consolidate all unstructured disturbances into a single quantity that can be estimated from data. Under mild assumptions, the resulting
stochastic predictor is causal and distributionally consistent, enabling efficient uncertainty quantification through
polynomial chaos expansions and higher-order Chebyshev inequalities. The proposed method is validated using experimental data from a smart home in Norway.
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All authors Guanru Pan, Dirk Reinhardt, Sebastien Gros, Timm Faulwasser
Signal Processing
Joint Mobile User Positioning and Passive Target Sensing using Optimized Sequential Beamforming
Aymen Hamrouni, Sofie Pollin and Hazem Sallouha
Integrated sensing and communication (
ISAC) relies on monostatic sensing (MS) and bistatic positioning (BP) to enable comprehensive environmental awareness and user localization. However, existing frameworks predominantly assume static geometries and optimize these modalities independently, neglecting user mobility and sequential information sharing. In this paper, we propose a velocity-aware sequential beamforming framework that dynamically couples MS and BP in time. We derive the Cramer-Rao bounds (CRBs) in the position domain to formulate a non-convex resource allocation problem. Instead of relying on static weighted-sum tradeoffs, we introduce a sequential
Bayesian optimization strategy where MS is executed first to construct a reliable structural prior on the UE and passive targets (PTs). This covariance prior is subsequently passed to the UE to regularize the BP estimation stage. We demonstrate that optimizing a single shared beamformer globally across both phases yields superior synergistic gains compared to a two-stage greedy approach. Simulation results validate that the shared sequential design efficiently balances limited symbol resources, achieving centimeter-level positioning accuracy for both the UE and PTs, robust velocity estimation, and a significantly reduced computational runtime.
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Image and Video Processing
Video Quality Evaluation Methodology and Result of AV2 Compression Performance
Zhijun Lei, Vibhoothi Vibhoothi, Dzung Hoang et al. (+2 more)
The Alliance for Open Media (AOMedia) has developed the AV2
video coding standard to supersede AV1, aiming for substantial compression efficiency gains across diverse media applications. This paper details the quality and performance evaluation methodology defined in the AV2 Common Test Conditions (CTC), which introduces new evaluation methods and content, including convex-hull-based adaptive streaming (AS) configuration, user-generated content (UGC), and extended chroma formats. We present the coding gains of the AV2 (v13.0) against the AV1 baseline. Experimental results show that AV2 achieves significant Bjøntegaard-Delta Rate (BD-rate) reductions of 29.81% and 33.79% for PSNR-YUV and VMAF, respectively, under random access configuration, validating the efficiency of AV2 for next-generation streaming applications.
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All authors Zhijun Lei, Vibhoothi Vibhoothi, Dzung Hoang, Yixin Du, Ramzi Khsib
Systems and Control · Cross-listed from cs.NI
The Shared Prosperity Internet
Juan A. Cabrera, Pit Hofmann, Jonas Schulz et al. (+5 more)
The Shared Prosperity Internet (SPI) is a network-computing architecture that makes the benefits of automation and Artificial Intelligence (AI) broadly accessible to the society. To ground its design, this paper maps the physical constraints of Shannon, Landauer, Turing, and Einstein to three design principles: trustworthiness, sustainability, and technological sovereignty, and maps them into three technical pillars: i) post-Shannon, goal-oriented communication that transmits only what the task requires; ii) anticipatory decision-making ("negative latency") with confidence-bounded pre-action and correction; and iii) beyond-digital computing that selects energy-optimal substrates under deadline and computability constraints. The SPI is grounded in three societal use cases: remote teaching for pupils, remote teaching of
robots and cyber-physical systems, and elder care. Furthermore, this paper defines measurable outcomes for an SPI, including latency decomposition, bits per event, energy and CO2 per task, safety and
privacy indicators, and robustness.
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All authors Juan A. Cabrera, Pit Hofmann, Jonas Schulz, Frederic Benken, Hrjehor Mark, Giang T. Nguyen, Holger Boche, Frank H. P. Fitzek
Signal Processing · Cross-listed from cs.LG
Learning Context-conditioned Gaussian Overbounds for Convolution-Based Uncertainty Propagation
Ruirui Liu, Xuejie Hou, Yiping Jiang et al. (+1 more)
Uncertainty quantification is essential in safety-critical settings–from autonomous driving to aviation, finance, and health–where decisions must rely on conservative bounds rather than point estimates. Predictor-level intervals (e.g., from
quantile regression, conformal prediction, variance networks, or
Bayesian models) generally do not compose: adding two per-variable intervals need not yield a valid interval for their sum or preserve coverage. In aviation, Gaussian overbounding replaces complex error distributions with a conservative Gaussian whose tails dominate the truth, so conservatism propagates through linear operations. Yet classical overbounds are global, often overly conservative, and hard to adapt to feature-conditioned errors. We propose a unified learning framework that trains neural networks to produce context-aware Gaussian overbounds–mean and scale–with provable conservatism on a finite
quantile grid and, under three explicit regularity assumptions, continuous-tail conservatism on a certified interval. Our overbounding loss enforces conservativeness at selected
quantiles while penalizing distributional distance with a Wasserstein-style term. The learned bounds support conservative linear-combination and convolution analysis on the enforced grid, and on the certified interval when assumptions hold, while being less redundant than traditional methods. We provide a scoped analysis of discrete-to-continuous conservatism and compact-domain objective regularity, and validate on synthetic data and real-world
datasets, including multipath, ionospheric, and tropospheric residual errors. Across these settings, the method yields tighter bounds while maintaining conservatism on the enforced grid and in experiments. The framework is modality-agnostic and applicable to learning systems that require conservative, feature-conditioned uncertainty estimates in dynamic environments.
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All authors Ruirui Liu, Xuejie Hou, Yiping Jiang, Hui Ren
Systems and Control · Cross-listed from cs.RO
Reactive Robot-Centric Safety for Autonomous Navigation in Constrained and Dynamic Environments
Viswa Narayanan Sankaranarayanan, Vignesh K. Viswanathan, Akshit Saradagi et al. (+2 more)
In this work, we address the problem of ensuring real-time safety in autonomous
robot navigation, in spatially constrained dynamic environments, by utilizing only onboard sensors. We present a real-time control architecture that integrates a 3D
LIDAR perception-based composite control barrier function(CBF)-based safety filter directly into the autonomy pipeline. The proposed perception-driven framework enforces collision avoidance constraints dynamically from onboard point cloud data, thus allowing a large number of constraints to be handled at the control frequency, while remaining minimally invasive to nominal task execution. The safety region is defined as an ellipsoid in the body-frame, consistent with the geometry of the platform, which induces time-varying constraints in the world frame as the
robot rotates; this effect is handled through a dedicated formulation of time-varying (CBF) for each
LIDAR point. We validate the system through multiple field experiments in underground environments by utilizing a quadruped platform performing a visual inspection task, demonstrating reliable operation in the presence of dynamic obstacles, unsafe high-level references, abrupt localization anomalies, and while traversing through narrow corridors.
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All authors Viswa Narayanan Sankaranarayanan, Vignesh K. Viswanathan, Akshit Saradagi, Sumeet Satpute, George Nikolakopoulos