Systems and Control
Evolutionary Dynamics in Continuous-time Finite-state Mean Field Games – Part II: Stability
Leonardo Pedroso, Andrea Agazzi, W.P.M.H. Heemels et al. (+1 more)
We study a dynamic game with a large population of players who choose actions from a finite set in continuous time. Each player has a state in a finite state space that evolves stochastically with their actions. A player's reward depends not only on their own state and action but also on the distribution of states and actions across the population, capturing effects such as congestion in traffic networks. In Part I, we introduced an evolutionary model and a new solution concept - the mixed stationary Nash
Equilibrium (MSNE) - which coincides with the rest points of the mean field evolutionary model under meaningful families of revision protocols. In this second part, we investigate the evolutionary stability of MSNE. We derive conditions on both the structure of the MSNE and the game's payoff map that ensure local and global stability under evolutionary dynamics. These results characterize when MSNE can robustly emerge and persist against strategic deviations, thereby providing insight into its long-term viability in large population dynamic games.
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All authors Leonardo Pedroso, Andrea Agazzi, W.P.M.H. Heemels, Mauro Salazar
Signal Processing
UAV SAR Imaging with 5G NR OFDM Signals in NLOS Environments
Qiuyuan Yang, Cunhua Pan, Ruidong Li et al. (+4 more)
The integration of sensing and communication (
ISAC) has significant potential for future wireless systems, enabling efficient spectrum utilization and novel application scenarios. In this paper, we propose a cooperative
ISAC framework for synthetic aperture radar (SAR) imaging by leveraging orthogonal frequency division multiplexing (OFDM) communication signals. We address the challenge of severe imaging degradation in non-line-of-sight (NLOS) environments under the QUAsi Deterministic
RadIo channel GenerAtor (QuaDRiGa). To detect weak signals and eliminate false points, we develop a two-stage compressed sensing-space alternating generalized expectation maximization (CS-SAGE) scheme for high-precision scatterer localization. In stage I, orthogonal matching pursuit (OMP) is employed for coarse estimation to identify the approximate locations of dominant scatterers. Then, the SAGE
algorithm in stage II performs fine estimation to accurately extract scatterer parameters. Simulation results validate the effectiveness of the proposed cooperative
ISAC framework, and provide valuable insights for practical system design.
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All authors Qiuyuan Yang, Cunhua Pan, Ruidong Li, Zhenkun Zhang, Hong Ren, Changhong Wang, Jiangzhou Wang
Signal Processing
Spectral-Convergent Decentralized Machine Learning: Theory and Application in Space Networks
Zhiyuan Zhai, Shuyan Hu, Wei Ni et al. (+2 more)
Decentralized machine learning (DML) supports collaborative training in large-scale networks with no central server. It is sensitive to the quality and reliability of inter-device communications that result in time-varying and
stochastic topologies. This paper studies the impact of unreliable communication on the convergence of DML and establishes a direct connection between the spectral properties of the mixing process and the global performance. We provide rigorous convergence guarantees under random
topologies and derive bounds that characterize the impact of the expected mixing
matrix's spectral properties on learning. We formulate a spectral optimization problem that minimizes the spectral radius of the expected second-order mixing
matrix to enhance the convergence rate under probabilistic link failures. To solve this non-smooth spectral problem in a fully decentralized manner, we design an efficient subgradient-based
algorithm that integrates Chebyshev-accelerated eigenvector estimation with local update and aggregation weight adjustment, while ensuring
symmetry and stochasticity constraints without central coordination. Experiments on a realistic low Earth orbit (LEO) satellite constellation with time-varying inter-satellite link models and real-world remote sensing data demonstrate the feasibility and effectiveness of the proposed method. The method significantly improves classification accuracy and convergence efficiency compared to existing baselines, validating its applicability in satellite and other decentralized systems.
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All authors Zhiyuan Zhai, Shuyan Hu, Wei Ni, Xiaojun Yuan, Xin Wang
Signal Processing
Diffusion-Driven Terahertz Air-Ground Communications under Dynamic Atmospheric Turbulence
Jinhao Yi, Weijun Gao and Chong Han
The ever-increasing demand for ultra-high data rates in space-air-ground integrated networks (SAGINs) has rendered terahertz THz communications a promising technology owing to its exceptionally broad and continuous spectrum resources. Nevertheless, in air-ground (AG) scenarios, the high mobility of aircraft induces intense and rapidly fluctuating
turbulence, leading to additional propagation loss that is often overlooked in existing studies. To bridge this gap, this paper presents an AI-empowered THz AG communication framework that explicitly models
turbulence-induced attenuation through fluid dynamics and integrates it into an adaptive optimization paradigm for communication performance enhancement. Specifically, a fluid-dynamics-informed attenuation model is established to characterize aircraft-generated
turbulence and quantify its impact on THz signal propagation. Building upon this model, a joint power-attitude optimization problem is formulated to adaptively allocate transmit power and adjust aircraft attitude for maximizing link capacity. The optimization problem is efficiently solved using a
diffusion-based
algorithm that learns the nonlinear relationship between flight configuration and
turbulence-induced attenuation. Comprehensive numerical evaluations demonstrate that the
turbulence-induced attenuation ranges from 18 to 28 dB under attacking angles between -10 degree and 10 degree at 0.7 Mach, verifying the pronounced impact of aircraft-induced
turbulence on THz propagation. Furthermore, the proposed framework attains an average capacity of 11.241 bps/Hz, substantially outperforming existing strategies by 22.8% and 66.5%, and approaching approximately 98% of the theoretical capacity limit.
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Signal Processing
Decentralized Federated Learning with Distributed Aggregation Weight Optimization
Zhiyuan Zhai, Xiaojun Yuan, Xin Wang et al. (+1 more)
Decentralized
federated learning (DFL) is an emerging paradigm to enable edge devices collaboratively training a learning model using a device-to-device (D2D) communication manner without the coordination of a parameter server (PS). Aggregation weights, also known as mixing weights, are crucial in DFL process, and impact the learning efficiency and accuracy. Conventional design relies on a so-called central entity to collect all local information and conduct system optimization to obtain appropriate weights. In this paper, we develop a distributed aggregation weight optimization
algorithm to align with the decentralized nature of DFL. We analyze convergence by quantitatively capturing the impact of the aggregation weights over decentralized communication networks. Based on the analysis, we then formulate a learning performance optimization problem by designing the aggregation weights to minimize the derived convergence bound. The optimization problem is further transformed as an
eigenvalue optimization problem and solved by our proposed subgradient-based
algorithm in a distributed fashion. In our
algorithm, edge devices only need local information to obtain the optimal aggregation weights through local (D2D) communications, just like the learning itself. Therefore, the optimization, communication, and learning process can be all conducted in a distributed fashion, which leads to a genuinely distributed DFL system. Numerical results demonstrate the superiority of the proposed
algorithm in practical DFL deployment.
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All authors Zhiyuan Zhai, Xiaojun Yuan, Xin Wang, Geoffrey Ye Li
Signal Processing
Integrated Sensing and Communication with UAV Swarms via Decentralized Consensus ADMM
Zhiyuan Zhai, Wei Ni, Xin Wang et al. (+2 more)
UAV swarms can form virtual
antenna arrays to exploit additional spatial degrees of freedom and enhance integrated sensing and communication (
ISAC). The optimization of
UAV positions is challenging due to the distributed nature of swarms and the lack of a global view at individual
UAVs. This paper presents a new decentralized optimization framework that allows
UAVs to decide their locations in parallel and reach consensus on a globally optimal swarm geometry for
ISAC. Specifically, we derive the achievable uplink rate and Cramér-Rao Bound (CRB) as tractable metrics for communication and sensing, respectively. The
UAV positions are optimized to balance maximizing the communication rate and minimizing the CRB. To solve this non-convex problem with coupled variables, we develop a decentralized consensus alternating direction method of multipliers (ADMM)
algorithm, which enables the
UAVs to iteratively align their local updates and reach consensus. The
algorithm decomposes the global objective into local projection updates, proxy-assisted consensus coordination, and lightweight dual updates, ensuring scalability and consistency throughout the swarm. Simulations demonstrate that the proposed consensus ADMM
algorithm converges rapidly with strong scalability, and that the
UAV swarm significantly outperforms fixed-array baselines in both communication and sensing performance.
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All authors Zhiyuan Zhai, Wei Ni, Xin Wang, Dusit Niyato, Ekram Hossain
Systems and Control · Cross-listed from math.NA
Computing the nearest $\Omega$-admissible descriptor dissipative Hamiltonian system
Vaishali Aggarwal, Nicolas Gillis and Punit Sharma
For a given set $\Omega \subseteq \mathbb{C}$, a
matrix pair $(E,A)$ is called $\Omega$-admissible if it is regular, impulse-free and its
eigenvalues lie inside the region $\Omega$. In this paper, we provide a dissipative
Hamiltonian characterization for the
matrix pairs that are $\Omega$-admissible where $\Omega$ is an LMI region. We then use these results for solving the nearest $\Omega$-admissible
matrix pair problem: Given a
matrix pair $(E,A)$, find the nearest $\Omega$-admissible pair $(\tilde E, \tilde A)$ to the given pair $(E,A)$. We illustrate our results on several data sets and compare with the state of the art.
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Signal Processing · Cross-listed from q-bio.NC
FAPEX: Fractional Amplitude-Phase Expressor for Robust Cross-Subject Seizure Prediction
Ruizhe Zheng, Lingyan Mao, Dingding Han et al. (+4 more)
Precise, generalizable subject-agnostic seizure prediction (SASP) remains a fundamental challenge due to the intrinsic complexity and significant spectral variability of electrophysiological signals across individuals and recording modalities. We propose FAPEX, a novel architecture that introduces a learnable fractional neural frame operator (FrNFO) for adaptive time-frequency decomposition. Unlike conventional models that exhibit spectral bias toward low frequencies, our FrNFO employs fractional-order convolutions to capture both high and low-frequency dynamics, achieving approximately 10% improvement in F1-score and sensitivity over state-of-the-art baselines. The FrNFO enables the extraction of instantaneous phase and amplitude representations that are particularly informative for preictal biomarker discovery and enhance out-of-distribution generalization. FAPEX further integrates structural state-space modeling and channelwise
attention, allowing it to handle heterogeneous electrode montages. Evaluated across 12
benchmarks spanning species (human, rat, dog, macaque) and modalities (Scalp-
EEG, SEEG, ECoG, LFP), FAPEX consistently outperforms 23 supervised and 10 self-supervised baselines under nested cross-validation, with gains of up to 15% in sensitivity on complex cross-domain scenarios. It further demonstrates superior performance in several external validation cohorts. To our knowledge, these establish FAPEX as the first epilepsy model to show consistent superiority in SASP, offering a promising solution for discovering epileptic biomarker evidence supporting the existence of a distinct and identifiable preictal state and clinical translation.
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All authors Ruizhe Zheng, Lingyan Mao, Dingding Han, Tian Luo, Yi Wang, Jing Ding, Yuguo Yu
Systems and Control
Theoretical and Experimental Limitations of RoCoF Estimation
Gutierrez-Florensa, F. Sanniti, D. Tedeschi et al. (+3 more)
A precise estimation of the Rate of Change of Frequency (RoCoF) is crucial for secure power system operation. In fact, RoCoF is strictly related to the amount of the available physical and/or virtual inertia of the system and the severity of the active power unbalance following a disturbance. For this reason, it is widely exploited in different protection systems, e.g., Anti-Islanding, Under Frequency Load Shedding (UFLS) and wide-area protection systems. The new paradigm of modern power systems, with a low-inertia and converter-based generation assets, is increasing the transient severity, making the frequency and the RoCoF estimation more complex and less precise for the actual devices. This work addresses this issue by proposing a numerically robust approach based on concepts inherited from differential geometry and fluid mechanics. The proposed approach is then tested with high-sampling real experimental measurements and used to develop a faster control logic for a RoCoF-based UFLS control scheme. The proposed approach provides information to protections regarding the nature of the contingency which can be used to improve its response.
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All authors Gutierrez-Florensa, F. Sanniti, D. Tedeschi, L. Sigrist, A. Ortega, F. Milano
Systems and Control
MHE in Output Feedback Control of Uncertain Nonlinear Systems via IQCs
Yang Guo and Stefan Streif
We propose a moving horizon estimation (MHE) scheme for general nonlinear constrained systems with parametric or static nonlinear uncertainties and a predetermined state feedback controller that is assumed to robustly stabilize the system in the absence of estimation errors. Leveraging integral quadratic constraints (IQCs), we introduce a new notion of detectability that is robust to possibly non-parametric uncertainties and verifiable in practice. Assuming that the uncertain system driven by the controller satisfies this notion of detectability, we provide an MHE formulation such that the closed-loop system formed of the uncertain system, the controller and MHE is input-to-state stable w.r.t. exogenous disturbances.
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Signal Processing
Multimodal-Wireless: A Large-Scale Dataset for Sensing and Communication
Tianhao Mao, Le Liang, Jie Yang et al. (+3 more)
This paper presents
Multimodal-Wireless, a large-scale open-source
dataset for
multimodal sensing and communication research. The
dataset is generated through an integrated and customizable data pipeline built upon the CARLA simulator and Sionna framework, and features high-resolution communication channel state information (CSI) fully synchronized with five other sensor modalities, namely
LiDAR, RGB and depth camera, inertial measurement unit (IMU) and radar, all sampled at 100 Hz. It contains approximately 160,000 frames collected across four virtual towns, sixteen communication scenarios, and three weather conditions. This paper provides a comprehensive overview of the
dataset, outlining its key features, overall framework, and technical implementation details. In addition, it explores potential research applications concerning communication and collaborative perception, exemplified by beam prediction using a
multimodal large
language model. The
dataset is open in https://le-liang.github.io/mmw/.
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All authors Tianhao Mao, Le Liang, Jie Yang, Hao Ye, Shi Jin, Geoffrey Ye Li
Image and Video Processing
SAIPAS: Simulating aspect-angles-invariant physical adversarial attacks on SAR target recognition models
Isar Lemeire, Yee Wei Law, Sang-Heon Lee et al. (+2 more)
Synthetic aperture radar (SAR) enables versatile, all-time, all-weather remote sensing. Coupled with automatic target recognition (ATR) leveraging machine learning (ML), SAR is empowering a wide range of Earth observation and surveillance applications. However, the surge of attacks based on
adversarial perturbations against the ML
algorithms underpinning SAR ATR is prompting the need for systematic research into
adversarial perturbation mechanisms. Research in this area began in the digital (image) domain and evolved into the (simulated) physical domain, resulting in physical
adversarial attacks (PAAs) that strategically exploit corner reflectors as attack vectors to evade ML-based ATR. Existing PAAs assume that the attacker knows the SAR platform's aspect angles, restricting their applicability to idealized scenarios. We propose the Simulated Aspect-angle-Invariant Physical
Adversarial SAR attack (SAIPAS), a framework that determines adversarially effective positions and orientations of any given set of reflectors, regardless of their number or size, even when the attacker lacks knowledge of the SAR platform's aspect angles. This is enabled by rigorous physics-based modeling of the reflected signal and the SAR imaging process. To facilitate mapping between image and scene coordinates, we additionally propose a method for generating bounding boxes in densely sampled azimuthal SAR images, allowing the target object to serve as a spatial reference. The resulting
adversarial configurations offer a clear physical interpretation while maintaining high fooling rates across continuous aspect trajectories under more realistic operational assumptions (69.1% for AConvNet for a four-reflector white-box attack). This paper has supplementary material available, which demonstrates the SAIPAS.
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All authors Isar Lemeire, Yee Wei Law, Sang-Heon Lee, William Meakin, Tat-Jun Chin
Systems and Control · Cross-listed from cs.RO
Collaborative Assembly Policy Learning of a Sightless Robot
Zeqing Zhang, Weifeng Lu, Lei Yang et al. (+3 more)
This paper explores a physical human-
robot collaboration (pHRC) task involving the joint insertion of a board into a frame by a sightless
robot and a human operator. While admittance control is commonly used in pHRC tasks, it can be challenging to measure the force/torque applied by the human for accurate human intent estimation, limiting the
robot's ability to assist in the collaborative task. Other methods that attempt to solve pHRC tasks using reinforcement learning (RL) are also unsuitable for the board-insertion task due to its safety constraints and sparse rewards. Therefore, we propose a novel RL approach that utilizes a human-designed admittance controller to facilitate more active
robot behavior and reduce human effort. Through simulation and real-world experiments, we demonstrate that our approach outperforms admittance control in terms of success rate and task completion time. Additionally, we observed a significant reduction in measured force/torque when using our proposed approach compared to admittance control. The
video of the experiments is available at https://youtu.be/va07Gw6YIog.
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All authors Zeqing Zhang, Weifeng Lu, Lei Yang, Wei Jing, Bowei Tang, Jia Pan
Systems and Control · Cross-listed from quant-ph
Frequency- and Amplitude-Modulated Gates for Universal Quantum Control
Qi Ding, Shoumik Chowdhury, Agustin Di Paolo et al. (+4 more)
Achieving high-fidelity single- and two-
qubit gates is essential for executing arbitrary digital
quantum algorithms and for building error-corrected
quantum computers. We propose a theoretical framework for implementing
quantum gates using frequency- and amplitude-modulated microwave control, which extends conventional amplitude modulation by introducing frequency modulation as an additional degree of control. Our approach operates on fixed-frequency
qubits, converting the need for
qubit frequency tunability into drive frequency modulation. Using Floquet theory, we analyze and design these drives for optimal fidelity within specified criteria. Our framework spans adiabatic to nonadiabatic gates within the Floquet framework, ensuring broad applicability across gate types and control schemes. Using typical transmon
qubit parameters in numerical simulations, we demonstrate a universal gate set-including the X, Hadamard, phase, and CZ gates-with control error well below 0.1% and gate times of 25-40 ns for single-
qubit operations and 125-135 ns for two-
qubit operations. Furthermore, we show an always-on CZ gate tailored for driven
qubits, which has gate times of 80-90 ns.
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All authors Qi Ding, Shoumik Chowdhury, Agustin Di Paolo, Réouven Assouly, Alan V. Oppenheim, Jeffrey A. Grover, William D. Oliver
Systems and Control
Active Noise Control Method Using Time Domain Neural Networks for Path Decoupling
Yijing Chu, Qinxuan Xiang, Sipei Zhao et al. (+3 more)
In decentralized active noise control (ANC) systems, crosstalk between multichannel secondary sources and error microphones significantly degrades control accuracy. Moreover, prefiltering reference signals in filtered-x (Fx) type
algorithms may further introduce modeling errors. A theoretical analysis of the Fx-based decentralized control
algorithm was performed, which reveals how prefiltering and crosstalk affect the control performance. Then, a hybrid method combining fixed-value neural networks and adaptive strategies was proposed for efficient decentralized ANC. The adaptive filter models the primary path of its own channel online using the least mean square (LMS)
algorithm while the neural network (named DecNet) is used for secondary paths inverting and decoupling. The hybrid DecNet-LMS
algorithm was implemented in the time domain to guarantee causality and avoid latency. Simulation results with measured acoustic paths show that the proposed method outperforms the existing ANC
algorithms using either traditional adaptive filters or neural network-based fixed-coefficient methods under different acoustic conditions.
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All authors Yijing Chu, Qinxuan Xiang, Sipei Zhao, Ming Wu, Y. Zhao, Guangzheng Yu
Signal Processing
Analysis and Algorithm for Multi IRS Collaborative Localization via Hybrid Time Angle Estimation
Ziheng Zhang, Wen Chen, Qingqing Wu et al. (+3 more)
This paper proposes a novel multiple intelligent reflecting surfaces (IRSs) collaborative hybrid localization system, which involves deploying multiple IRSs near the target area and achieving target localization through joint time delay and angle estimation. Specifically, echo signals from all reflective elements are received by each sensor and jointly processed to estimate the time delay and angle parameters. Based on the above model, we derive the Fisher Information
Matrix (FIM) for cascaded delay, Angle of Arrival (AOA), and Angle of Departure (AOD) estimation in semi passive passive models, along with the corresponding Cramer Rao Bound (CRB). To achieve precise estimation close to the CRB, we design efficient
algorithms for angle and location estimation. For angle estimation, reflective signals are categorized into three cases based on their rank, with different signal preprocessing. By constructing an atomic norm set and minimizing the atomic norm, the joint angle estimation problem is transformed into a convex optimization problem, and low-complexity estimation of multiple AOA and AOD pairs is achieved using the Alternating Direction Method of Multipliers (ADMM). For location estimation, we propose a three-stage localization
algorithm that combines weighted least squares, total least squares, and quadratic correction to handle errors in the coefficient
matrix and observation vector, thus improving accuracy. Numerical simulations validate the superiority of the proposed system, demonstrating that the system's collaboration, hybrid localization, and distributed deployment provide substantial benefits, as well as the accuracy of the proposed estimation
algorithms, particularly in low signal to noise ratio (SNR) condition.
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All authors Ziheng Zhang, Wen Chen, Qingqing Wu, Haoran Qin, Zhendong Li, Qiong Wu
Signal Processing
Consensus Tracking of an Underwater Vehicle Using Weighted Harmonic Mean Density
Ved Prakash Dubey and Shovan Bhaumik
This paper addresses an
underwater target tracking problem in which a large number of sonobuoy sensors are deployed on a surveillance region. The region is divided into several sub-regions, where a single tracker, capable of generating track is installed. Each sonobuoy can measure the direction of arrival of acoustic signals (known as bearing angles) and communicate the measurements with the local tracker. Further, each local tracker can communicate with all other trackers, where each of them can exchange their estimate and finally a consensus is reached. We propose a weighted harmonic mean density (HMD) based tracking to reach a consensus and provide a solution for the fusion of Gaussian densities. In this approach, optimal weights are assigned by minimizing the Kullback-Leibler divergence measure. Performance of the proposed method is measured using root mean square error, percentage of track divergence, and normalized estimation error squared. Simulation results demonstrate that the optimized HMD-based fusion outperforms existing fusion methods during a distributed tracking.
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Systems and Control · Cross-listed from cs.CL
Control Barrier Function for Aligning Large Language Models
Yuya Miyaoka and Masaki Inoue
This paper proposes a control-based framework for aligning large
language models (LLMs) by leveraging a control barrier function (CBF) to ensure user-desirable text generation. The presented framework applies the CBF safety filter to the predicted
token generated from the baseline LLM, to intervene in the generated text. The safety filter includes two significant advantages: this safety filter is an add-on type, allowing it to be used for
alignment purposes without fine-tuning the baseline LLM, and if there is an evaluation model regarding the desired
alignment, it can be directly applied to the filter design. The overall text-generation system is implemented with open-source
language models, aiming to generate positive text.
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Systems and Control · Cross-listed from quant-ph
D2-UC: A Distributed-Distributed Quantum-Classical Framework for Unit Commitment
Milad Hasanzadeh and Amin Kargarian
This paper introduces D2-UC, a
quantum-ready framework for the unit commitment (UC) problem that prepares UC for near-term hybrid
quantum-classical solvers by combining distributed classical decomposition with distributed
quantum execution. We reformulate deterministic and
stochastic UC into a three-block alternating direction method of multipliers (ADMM): (i) a convex quadratic subproblem for dispatch and reserves, (ii) a binary subproblem expressed as a quadratic unconstrained binary optimization (QUBO), and (iii) a proximal slack update for consensus. The core contributions are fivefold. First, we demonstrate how the full UC problem can be expressed as a single monolithic QUBO, establishing a direct interface to
quantum solvers. Second, we decompose this large binary block into three type-specific QUBOs for commitment, startup, and shutdown, making the problem more tractable but revealing slower ADMM convergence. Third, we restore local logical couplings through per-unit-time micro-QUBOs, which accelerate convergence. Fourth, we batch micro-QUBOs into K non-overlapping block-diagonal problems, reducing many subproblems to a fixed number of solver-ready QUBOs per iteration, compatible with distributed variational
quantum eigensolvers (DVQE). Fifth, we integrate an accept-if-better safeguard with DVQE to stabilize hybrid updates and prevent oscillations. Case studies confirm that the proposed methods deliver feasible schedules, faster convergence, and QUBO sizes aligned with current and near-term
quantum hardware capabilities. All detailed data, codes, and parameter values are available at https://github.com/LSU-RAISE-LAB/3B-ADMM-UC-DVQE .
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Image and Video Processing · Cross-listed from cs.CV
ISC-Perception: A Hybrid Computer Vision Dataset for Object Detection in Novel Steel Assembly
Miftahur Rahman, Samuel Adebayo, Dorian A. Acevedo-Mejia et al. (+4 more)
The Intermeshed Steel Connection (ISC) system, when paired with robotic manipulators, can accelerate steel-frame assembly and improve worker safety by eliminating manual assembly. Dependable perception is one of the initial stages for ISC-aware
robots. However, this is hampered by the absence of a dedicated image corpus, as collecting photographs on active construction sites is logistically difficult and raises safety and
privacy concerns. In response, we introduce ISC-Perception, the first hybrid
dataset expressly designed for ISC component detection. It blends procedurally rendered CAD images, game-engine photorealistic scenes, and a limited, curated set of real photographs, enabling fully automatic labelling of the synthetic portion. We explicitly account for all human effort to produce the
dataset, including simulation engine and scene setup, asset preparation, post-processing scripts and quality checks; our total human time to generate a 10,000-image
dataset was 30.5,h versus 166.7,h for manual labelling at 60,s per image (-81.7%). A manual pilot on a representative image with five instances of ISC members took 60,s (maximum 80,s), anchoring the manual baseline. Detectors trained on ISC-Perception achieved a mean Average Precision at IoU 0.50 of 0.756, substantially surpassing models trained on synthetic-only or photorealistic-only data. On a 1,200-frame bench test, we report mAP@0.50/mAP@[0.50:0.95] of 0.943/0.823. By bridging the data gap for construction-robotics perception, ISC-Perception facilitates rapid development of custom object detectors and is freely available for research and industrial use upon request.
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All authors Miftahur Rahman, Samuel Adebayo, Dorian A. Acevedo-Mejia, David Hester, Daniel McPolin, Karen Rafferty, Debra F. Laefer
Audio and Speech Processing · Cross-listed from cs.CL
A Computational Approach to Analyzing Disrupted Language in Schizophrenia: Integrating Surprisal and Coherence Measures
Gowtham Premananth and Carol Espy-Wilson
Language disruptions are one of the well-known effects of schizophrenia symptoms. They are often manifested as disorganized
speech and impaired discourse coherence. These abnormalities in spontaneous
language production reflect underlying cognitive disturbances and have the potential to serve as objective markers for symptom severity and diagnosis of schizophrenia. This study focuses on how these
language disruptions can be characterized in terms of two computational linguistic measures: surprisal and semantic coherence. By computing surprisal and semantic coherence of
language using computational models, this study investigates how they differ between subjects with schizophrenia and healthy controls. Furthermore, this study provides further insight into how
language disruptions in terms of these linguistic measures change with varying degrees of schizophrenia symptom severity.
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Audio and Speech Processing
Speech-Based Prioritization for Schizophrenia Intervention
Gowtham Premananth, Philip Resnik, Sonia Bansal et al. (+2 more)
Millions of people suffer from mental health conditions, yet many remain undiagnosed or receive delayed care due to limited clinical resources and labor-intensive assessment methods. While most machine-assisted approaches focus on diagnostic classification, estimating symptom severity is essential for prioritizing care, particularly in resource-constrained settings.
Speech-based AI provides a scalable alternative by enabling automated, continuous, and remote monitoring, reducing reliance on subjective self-reports and time-consuming evaluations. In this paper, we introduce a
speech-based model for pairwise comparison of schizophrenia symptom severity, leveraging articulatory and acoustic features. These comparisons are used to generate severity rankings via the Bradley-Terry model. Our approach outperforms previous regression-based models on ranking-based metrics, offering a more effective solution for clinical triage and prioritization.
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All authors Gowtham Premananth, Philip Resnik, Sonia Bansal, Deanna L.Kelly, Carol Espy-Wilson
Audio and Speech Processing
Quantifying Articulatory Coordination as a Biomarker for Schizophrenia
Gowtham Premananth and Carol Espy-Wilson
Advances in artificial intelligence (AI) and deep learning have improved diagnostic capabilities in healthcare, yet limited interpretability continues to hinder clinical adoption. Schizophrenia, a complex disorder with diverse symptoms including disorganized
speech and social withdrawal, demands tools that capture symptom severity and provide clinically meaningful insights beyond binary diagnosis. Here, we present an interpretable framework that leverages articulatory
speech features through eigenspectra difference plots and a weighted sum with exponential decay (WSED) to quantify vocal tract coordination. Eigenspectra plots effectively distinguished complex from simpler coordination patterns, and WSED scores reliably separated these groups, with ambiguity confined to a narrow range near zero. Importantly, WSED scores correlated not only with overall BPRS severity but also with the balance between positive and negative symptoms, reflecting more complex coordination in subjects with pronounced positive symptoms and the opposite trend for stronger negative symptoms. This approach offers a transparent, severity-sensitive biomarker for schizophrenia, advancing the potential for clinically interpretable
speech-based assessment tools.
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