Systems and Control · Cross-listed from cs.AI
Offline AI Modules: Voice-First Offline Architecture, Hardware Reference Stack, Quantization and Benchmarking
Sunday Afariogun, Odunolaoluwa Jenrola and Zeinab Nezami
The Offline AI Modules workstream enables practical, low-power, and community-accessible deployment of voice-first AI systems that operate fully offline. Designed for African
language communities where
speech is the dominant mode of interaction and internet connectivity is unreliable or absent, the workstream delivers three reinforcing components: a modular voice-first offline architecture, a low-cost hardware reference bill of materials, and a reproducible quantization and a reproducible quantization and benchmarking pipeline for instruction-tuned
language models in the 2-5B parameter class. This paper presents the first end-to-end
benchmark evaluation of the stack across two hardware tiers: an NVIDIA Jetson Orin NX (TierB) and a Raspberry Pi5 (TierA). Three instruction-tuned models are evaluated across four quantization formats, assessed for deployment metrics (decode throughput, chat latency,
memory, power) and multilingual quality (topic classification accuracy on MasakhaNEWS across English, Hausa, Igbo, Nigerian Pidgin, and Yoruba; per-
language perplexity drift).
Speech recognition is evaluated using Ethio-ASR on Amharic and Oromo across both tiers. The principal finding is that Q4_K_M quantization represents the best size-to-quality trade-off for deployment on both tiers: gemma-4-E2B-it achieves 28.8t/s decode throughput and 89.2% topic classification accuracy at Q4_K_M on TierB, while all three models run within the 16GB
memory budget on TierA.
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Systems and Control
Frequency-Dependent Breakdown of Litz-Wire Insulation Under Repetitive Bipolar Square-Wave Voltages
Md Asifur Rahman, Farzana Islam and Mona Ghassemi
This paper investigates the dielectric breakdown behavior of Litz wire insulation subjected to repetitive fast-edge bipolar square-wave voltages representative of wide-bandgap (WBG) power converter stress. Two conductor sizes, 14 AWG and 16 AWG, were tested in a twisted-pair configuration over frequencies ranging from 1 kHz to 30 kHz using a controlled high-voltage pulse generator with 200 ns rise time. The breakdown voltages obtained at each frequency were statistically analyzed using the weighted two-parameter Weibull method in accordance with IEEE Std 930-2004. Between 1 and 30 kHz, the mean breakdown voltage decreases by approximately 10.7% for the 14 AWG construction and 20.0% for the 16 AWG construction. The 14 AWG specimens exhibit a modest increase between 1 and 5 kHz followed by a decline, whereas the 16 AWG mean decreases across the tested frequencies. The Weibull shape parameter varies nonmonotonically with frequency, characterizing differences in the dispersion of the measured breakdown voltages. These findings provide construction-specific breakdown data relevant to Litz-wire insulation assessment in high-frequency power electronic applications. Possible contributions from charge accumulation, localized discharge activity, and dielectric heating are discussed, but were not directly verified in this study.
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Systems and Control · Cross-listed from math.DS
On global Lyapunov functions being Morse
Wouter Jongeneel
Lyapunov functions have been a cornerstone of dynamical systems theory ever since the early 1900s. Moreover and akin to Morse theory, Lyapunov functions have been the key in linking
topology to dynamical systems theory. In this note we continue along these lines. Suppose that some vector field on Euclidean space has a unique
equilibrium point that is globally asymptotically stable (GAS). Under these conditions, it is known that there is always a smooth Lyapunov function to certify stability. One may wonder if this function can always be chosen to be Morse. We show that if the
equilibrium point is
hyperbolic, this is indeed true. Moreover, we show that if this would be true in general, then the generalized 4-dimensional smooth Poincaré
conjecture (SPC4) must be true. Even so, we provide an example that is GAS, but does not admit a Morse Lyapunov function, closing this route of proving SPC4.
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Systems and Control · Cross-listed from cs.RO
Emergency Obstacle Avoidance Maneuvers in Differential-Drive Mobile Robots
Kautik Mandve and Nilay Kant
Emergency obstacle avoidance requires a mobile
robot to brake or change its heading within the available distance. This paper investigates the dependence of maneuver performance and odometric error on approach speed for a differential-drive
robot. A footprint-clearance analysis and a normalized wheel-motion index provide a kinematic description of five braking and turning maneuvers. The principal experiment comprises 540 block-randomized trials on tile, of which 539 are retained, at commanded approach speeds of 45, 55, and 65 cm/s. An overhead camera provides an independent pose reference. When encoder, gyro, and camera heading changes are evaluated over complete motion records, the mean encoder discrepancy increases by 4.7-5.1 degrees for the two reverse-
spin maneuvers between the lowest and highest speeds; the arc and brake-assisted pivot change by less than 0.4 degrees. Larger encoder discrepancy is associated with lower avoidance success after adjustment for distance, speed, maneuver, day, and turn direction. Gyro discrepancies remain approximately 3 degrees for the reverse
spins. Estimated reaction distances for 90% success and their uncertainty quantify the maneuver trade-offs. The results support speed-specific empirical characterization of emergency maneuvers and distinguish encoder error from recovery motion and measurement-window mismatch.
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Systems and Control · Cross-listed from cs.LO
Scenario-Based Compositional Statistical Model Checking for Safety Specifications
Abhinav Pomalapally, Arya Raeesi, Kevin Kai-Chun Chang et al. (+2 more)
In safety-critical domains such as autonomous driving, systems must be evaluated across a large number of environment conditions, often represented as composite scenarios built from primitive scenarios. Existing statistical model checking (SMC) approaches analyze each composite scenario independently, requiring many expensive simulations and resulting in substantial redundant computation when scenarios share common structure. This work introduces a scenario-based compositional SMC framework for safety and co-safety specifications, enabling efficient analysis of composite scenarios. Our approach decomposes scenarios into primitives and specifications into sub-specifications, verifies each primitive independently, and composes the resulting statistical estimates using importance sampling and kernel density estimation. Our empirical evaluation shows that the proposed framework can accurately answer verification queries for previously unseen composite scenarios while reducing simulation cost through parallelization and trace reuse.
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All authors Abhinav Pomalapally, Arya Raeesi, Kevin Kai-Chun Chang, Beyazit Yalcinkaya, Sanjit A. Seshia
Audio and Speech Processing · Cross-listed from cs.LG
Joint Estimation of Common-Slope Decay Rates and Spatial Amplitudes Using Parameterized Nonnegative Matrix Factorization
Jeremy B. Bai, Filip Elvander and Sebastian J. Schlecht
We formulate joint estimation of common-slope decay rates and amplitudes from room impulse responses (RIRs) as parameterized nonnegative
matrix factorization with the Itakura–Saito divergence as the loss function (IS-NMF). Estimation at each short-time
Fourier transform frequency bin produces detailed reverberation time (RT) curves directly from RIR powers with no backward integration needed. Standard space-alternating generalized expectation-maximization (SAGE)
algorithm yields closed-form amplitude updates and a convex subproblem for each decay rate update. To accelerate estimation, we introduce contribution-weighted SAGE, which emphasizes observations where each component contributes strongly to the modeled power. Experiments with synthetic data show accurate recovery of well-separated decays and faster loss reduction than standard SAGE. Application to measured coupled-room RIRs yields frequency-dependent RT curves and reveals complementary space-time contributions of the shared decay components.
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Systems and Control
The asymptotic variance of the Hermite-Domain Predictor-Based Subspace Identification method
Enrico Barbiero and Marco Lovera
This paper derives analytical expressions for the asymptotic variance of the Hermite-Domain Predictor-Based Subspace Identification (HD-PBSID) method. Unlike continuous-time subspace approaches that rely on intermediate-domain transformations, HD-PBSID identifies continuous-time state-space
matrices directly. The derivation first establishes the uncertainty of the estimated state-space
matrices and then exploits these results to obtain asymptotic variance expressions. These expressions provide analytical uncertainty bounds for system
eigenvalues, which are invariant under similarity transformations and therefore uniquely characterize the identified dynamics. The proposed formulas are first validated in an ideal Hermite-domain setting, where the conditions underlying the derivation are satisfied, and then assessed on noisy time-domain data through Monte Carlo simulations. The predicted bounds show very good agreement with the
eigenvalue distributions in the ideal setting and acceptable agreement in the time-domain case when the innovation sequence is enforced to be white.
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Signal Processing
AngularWM: Wireless World Modeling for AoA Prediction from Multi-Antenna I/Q
Omar Mashaal and Hatem Abou-Zeid
Tracking angle-of-arrival (AoA) under mobility enables proactive beam
alignment in multi-
antenna wireless systems. However, learning this
evolution directly from raw I/Q data is challenging because multipath, channel-gain variations, hardware impairments, and noise mix with angular information. This paper proposes AngularWM, a self-supervised wireless world-modeling approach that learns a predictive latent angular state from ordered multi-
antenna I/Q observations. A joint-
embedding predictive architecture is combined with a label-free trajectory-level
geometric regularizer that encourages an approximately affine, non-collapsed latent
evolution motivated by the
antenna-array response. No AoA, motion, or displacement labels are used during pretraining. The resulting structured world state supports direct multi-step encoder-space extrapolation and generalizes to angular step sizes not seen during training. On large-scale over-the-air measurements, AngularWM reduces the mean predictor-free AoA error over eight steps from $29.97^\circ$ to $0.49^\circ$. After pretraining, only three or four labeled reference angles are required to calibrate the complete 225-point AoA grid, achieving $0.48^\circ$ and $0.43^\circ$ MAE, respectively. AngularWM also maintains robust beam
alignment and spectral efficiency under increasing angular displacement, while reducing the deployed model size from 1.42M to 0.30M parameters and forecast latency.
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Systems and Control
Optimal Dynamic Resource Allocation for Multicore Real-time Systems
Georgiy A. Bondar, Abigail Eisenklam, Ripon C. Sarker et al. (+2 more)
We formulate a novel optimal control problem for data-driven dynamic resource allocation in multicore real-time systems. The proposed formulation accounts for hard deadline constraints and resource bounds. Under mild assumptions, we prove several results on the feasibility and existence of optimal solution for the proposed formulation. Building on these analyses, we design an
algorithm to solve the multi-core dynamic resource allocation problem. We demonstrate the practical use of this new
algorithm by experimentally evaluating it on a real multicore platform using four
benchmarks from the literature.
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All authors Georgiy A. Bondar, Abigail Eisenklam, Ripon C. Sarker, Linh Thi Xuan Phan, Abhishek Halder
Signal Processing
Bistatic ISAC under Data Payload Uncertainty
Musa Furkan Keskin, Silvia Mura, Marouan Mizmizi et al. (+3 more)
We investigate the problem of data payload uncertainty (DPU) in bistatic integrated sensing and communication (
ISAC) systems, which refers to imperfect knowledge of transmit data symbols at the sensing receiver. DPU may result from limited fronthaul capacity in base station (BS)-to-BS bistatic sensing or data demodulation errors in BS-to-user equipment (UE) bistatic sensing, and can impair target detection through elevated sidelobe levels in the delay-Doppler domain. To characterize this effect, we derive closed-form expressions for the peak-to-sidelobe level ratio (PSLR) of two common OFDM receivers, namely reciprocal filtering (RF) and matched filtering (MF), under DPU. The analysis shows that the DPU-induced sidelobe degradation of RF depends on the inverse second-, fourth-, and sixth-order constellation moments, whereas that of MF depends only on the direct fourth-order moment, making RF considerably more vulnerable to DPU. To mitigate the resulting sidelobes, we further propose a novel, DPU-aware minimum mean-squared-error (MMSE) receiver. Simulation results validate the PSLR analysis and demonstrate superior detection performance of MMSE over RF and MF while revealing the extent to which it can recover DPU-induced performance loss relative to a genie-aided receiver with perfect knowledge of data payload.
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All authors Musa Furkan Keskin, Silvia Mura, Marouan Mizmizi, Dario Tagliaferri, Fan Liu, Henk Wymeersch
Signal Processing
One-Shot Beam Tracking for Stacked Intelligent Metasurfaces-Assisted LEO Broadcasting
Chandan Kumar Sheemar, Giovanni Iacovelli, Sourabh Solanki et al. (+2 more)
This letter develops a physics-informed one-shot beam tracking method for stacked intelligent metasurface (SIM)-enabled low-Earth-orbit (LEO) links with $K$ users and an $L$-layer SIM with $N$ meta-atoms per layer. The predictable orbital motion is propagated through the line-of-sight (LoS) geometry to forecast the finite-interval variation of the user signal-to-noise ratio (SNR) profile, and an analytical multilayer Jacobian relates this variation to the $LN$ SIM phase coefficients. Beam tracking is formulated as normalized SNR-profile preservation and solved through a single regularized Gauss–Newton correction that requires one Jacobian evaluation and a $K\times K$ linear solve, thereby avoiding iterative reoptimization. A tracking-error bound separates the regularization residual from the nonlinear Taylor remainder and establishes a second-order local error under a full-row-rank Jacobian. Numerical results show that the proposed method retains approximately $94\%$ and $92\%$ of the iterative-reoptimization rate for $L=2$ and $L=4$, respectively, while running about $350\times$ and $260\times$ faster at $N=225$, and confirm the predicted second-order residual error behavior.
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All authors Chandan Kumar Sheemar, Giovanni Iacovelli, Sourabh Solanki, Wali Ullah Khan, Symeon Chatzinotas
Systems and Control · Cross-listed from cs.MA
Distributed Algorithms for $\alpha$-Potential Functions in General-Sum Games
Yifei Chen and Chinmay Maheshwari
We study the problem of computing the tightest \(\alpha\)-potential approximation of a general-sum game over continuous action spaces, within a prescribed class of potential functions and when each player has access only to its own utility function. The difficulty is twofold: the approximation error involves a worst-case search over an infinite set of unilateral deviations, and the required utility information is distributed across players. For a linear-in-parameters potential class, we use an exact finite-tuple reformulation that separates the problem into a global outer search over deviation tuples and distributed convex inner problems. We develop a primal–dual inner oracle tailored to this structure and establish a uniform one-sided accuracy guarantee. This oracle can be combined with global outer search to obtain an end-to-end guarantee on the outer optimization error. We also develop a projected zeroth-order outer method as a computationally lighter alternative for higher-dimensional problems. Numerical experiments illustrate the accuracy–computation tradeoff between the two outer-search methods and show that the proposed optimization framework can improve upon analytical \(\alpha\)-potential constructions.
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Signal Processing · Cross-listed from math.ST
Rank-one variance inflation in polynomial estimation of signal parameters with a sign-preserving fractional-power basis
Serhii Zabolotnii
The
polynomial maximization method estimates signal parameters in non-Gaussian noise from a finite description of the noise by its moments and cumulants, without a density. Known accuracy results assume that these noise characteristics are known, or use a design in which estimating them jointly costs no accuracy. In practice they are estimated from the residuals of a preliminary fit, and the effect of this substitution on accuracy is unknown. We treat the feasible scheme as a two-step
estimator and, for a general smooth signal model in a fixed design, find the increment of its asymptotic covariance in closed form: $\Sigma_{\rm fe}-\Sigma_{\rm or}=c_2(1-g_{\rm or}) Q^{-1}\bar{d}\bar{d}^{\top}Q^{-1}$, a positive semidefinite
matrix of rank at most one. Here $c_2$ is the noise variance, $g_{\rm or}\le 1$ the oracle variance reduction factor, and $Q$ and $\bar{d}$ the second-moment
matrix and mean of the signal gradient over the design. Estimating the fractional moments that form the weights costs no first-order accuracy, because that block is orthogonal; the whole increment comes from estimating the sign-preserving centering means. The increment lies along the single direction $Q^{-1}\bar{d}$, so linear combinations of the parameters orthogonal to it keep oracle accuracy. In the trace metric the variance reduction factor becomes $g_{\rm fe}=g_{\rm or}+(1-g_{\rm or})R_D$, where $R_D=\|Q^{-1}\bar{d}\|^2/{\rm tr} Q^{-1}$ depends on the design alone. We give four sufficient conditions for first-order oracle equivalence; noise
symmetry is not among them. Monte Carlo experiments with a harmonic signal confirm the direction and size of the increment. A covariance estimate that ignores the increment undercovers where non-Gaussianity gives the largest gain, symmetric noise included.
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Systems and Control
New and Improved Analytical Methods for Calculating Power System Adequacy Metrics
Chanan Singh
A new analytical technique is proposed for calculating adequacy metrics for generation planning. The proposed technique is simple, direct, and provides higher accuracy than traditional discretized approaches. Additionally, a new analytical methodology is introduced for calculating loss of load days (LOL Days) as distinct from loss of load events or frequency of load loss. This paper emphasizes that, where feasible, analytical methods are preferable to Monte Carlo simulations because they yield exact closed-form solutions rather than statistical estimates.
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Signal Processing · Cross-listed from cs.LG
Lightweight Semantic EEG Foundation Model for Frozen Cross-Disorder Transfer
Rita Huan-Ting Peng and Nhat Bui
Large-scale
EEG foundation models have demonstrated promising transferability across neurological disorders, but often require millions of parameters and substantial computational resources. In this paper, we present the Universal Semantic
EEG Foundation Model (USE-FM), a lightweight
EEG foundation model that learns transferable neural representations through self-supervised signal reconstruction on the Temple University Hospital
EEG Corpus (TUEG). After pretraining, the encoder is frozen and evaluated on two clinically distinct downstream tasks, abnormal
EEG detection (TUAB) and epileptic seizure recognition (TUEP), using a unified frozen-transfer protocol against recent
EEG foundation models, including LUNA-Base and CBraMod. With only 1.46 million parameters, approximately one-fifth the size of existing models, USE-FM achieves competitive overall performance, including strong sensitivity and F1-score on TUEP (SEN $75.00 \pm 14.14$, F1 $70.37 \pm 4.01$), while maintaining competitive performance on TUAB (AUC $85.24 \pm 5.61$). Beyond downstream classification, latent representation analysis using $k$-means clustering together with PCA and t-SNE demonstrates that USE-FM learns organized semantic
EEG representations comparable to substantially larger foundation models. These results suggest that large-scale self-supervised pretraining enables lightweight architectures to learn transferable semantic
EEG representations, providing a computationally efficient foundation for cross-disorder analysis and future clinical decision support in neurological disorders.
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Systems and Control
Unlocking AI Data Center Interconnection Capacity Through Coordinated Grid and Data Center Flexibility
Rida Fatima and Xingpeng Li
The rapid growth of AI data centers is creating concentrated electricity demands that can exceed available distribution network headroom and delay interconnection. This paper investigates whether capacity can be used effectively by coordinating flexibility on both sides of the interconnection. A day-ahead mixed integer second order cone programming framework maximizes feasible AI data center IT capacity using utility side conservation voltage reduction and network
topology reconfiguration, together with data center workload shifting and reserve constrained uninterruptible power supply storage. Background feeder demand uses voltage dependent ZIP models, while the data center is modeled as constant power demand using Training, Inference, and Mixed workload profiles. A two-stage solution first maximizes interconnection capacity and then minimizes feeder losses for the retained capacity, with numerical relaxation screening. Studies on a 116-bus model derived from the IEEE 123-node feeder show that, at the constrained bus-60 connection point, grid side flexibility, driven almost entirely by network reconfiguration, increases feasible IT capacity by approximately 42.5-45.0%, while data center flexibility alone provides approximately 2.1-5.4% gains. Coordinated operation increases feasible IT capacity from approximately 10.5-10.6 MW under BASE operation to 15.3-16.0 MW, corresponding to gains of approximately 45.9-50.8%; the 16.0 MW Inference result is limited by the adopted UPS reserve requirement. Benefits are strongly location dependent and influenced by workload flexibility, deferral duration, PUE, UPS energy and reserve requirements, and feeder loading. Under a combined adverse operating condition, FULL capacity decreases by only 3.4% relative to the nominal Mixed case while retaining substantial additional capacity over BASE.
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Signal Processing
RF-Agent: Hierarchical Language-Agent Control for Instruction-Conditioned Active Spectrum Sensing
Hao Zhang, Dongfang Xu, Hang Zou et al. (+7 more)
Active
radio-frequency (RF) sensing must acquire evidence under receiver limits while following confirmation, recovery, and stopping instructions. \newhl{We propose RF-
Agent, a closed-loop architecture combining
language supervision, episode
memory, deterministic RF execution, perception feedback, and evidence-based reporting.} An independent auditor checks trajectory compliance. We derive acquisition and supervisory-request bounds, characterize full-history
token complexity, and bound joint success by output validity and evidence capacity. \newhl{ActiveRF-AD tests instruction changes at fixed states and evaluates joint success, requiring compliance and RF correctness in the same episode.} \newhl{Training on different instructions at shared sensing states raises counterfactual-pair accuracy from 24.03% to 96.22% and Core joint success from 65.13% to 72.12%. Of the 6.99-point joint-success gain, 6.73 points reflect a decrease in the fraction of all episodes that are RF-correct but noncompliant.} \newhl{At Core budget three, paired-training hierarchical control achieves 66.60% joint success versus 9.17% for direct-action control.} \newhl{In a separate comparison at the same budget, RF-
Agent improves joint success by 2.31 points and reduces RF acquisitions by 12.3% relative to an initial-state planner, at increased inference cost.} Cross-backbone diagnostics cover three model families. These results show how instruction-responsive control improves task completion beyond what RF accuracy alone reveals.
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All authors Hao Zhang, Dongfang Xu, Hang Zou, Anis Bara, Brahim Mefgouda, Lina Bariah, Yuzhi Yang, Fuhui Zhou, Qihui Wu, Merouane Debbah