pwc-archive/papers-with-abstracts huggingface dataset:
Artificial Intelligence in archival and historical scholarship workflow: HTS and ChatGPT
Authors: Salvatore Spina
Date: 2023-07-05 00:00:00

This article examines the impact of Artificial Intelligence on the archival heritage digitization processes, specifically regarding the manuscripts' automatic transcription, their correction, and normalization. It highlights how digitality has compelled scholars to redefine Archive and History field and has facilitated the accessibility of analogue sources through digitization and integration into big data. The study focuses on two AI systems, namely Transkribus and ChatGPT, which enable efficient analysis and transcription of digitized sources. The article presents a test of ChatGPT, which was utilized to normalize the text of 366 letters stored in the Correspondence section of the Biscari Archive (Catania). Although the AI exhibited some limitations that resulted in inaccuracies, the corrected texts met expectations. Overall, the article concludes that digitization and AI can significantly enhance archival and historical research by allowing the analysis of vast amounts of data and the application of computational linguistic tools.
Self-Supervised Learning for WiFi CSI-Based Human Activity Recognition: A Systematic Study
Authors: Ke Xu, Jiangtao Wang, Hongyuan Zhu, Dingchang Zheng
Date: 2023-07-19 00:00:00
Tasks: Activity Recognition, Human Activity Recognition, Self-Supervised Learning

Recently, with the advancement of the Internet of Things (IoT), WiFi CSI-based HAR has gained increasing attention from academic and industry communities. By integrating the deep learning technology with CSI-based HAR, researchers achieve state-of-the-art performance without the need of expert knowledge. However, the scarcity of labeled CSI data remains the most prominent challenge when applying deep learning models in the context of CSI-based HAR due to the privacy and incomprehensibility of CSI-based HAR data. On the other hand, SSL has emerged as a promising approach for learning meaningful representations from data without heavy reliance on labeled examples. Therefore, considerable efforts have been made to address the challenge of insufficient data in deep learning by leveraging SSL algorithms. In this paper, we undertake a comprehensive inventory and analysis of the potential held by different categories of SSL algorithms, including those that have been previously studied and those that have not yet been explored, within the field. We provide an in-depth investigation of SSL algorithms in the context of WiFi CSI-based HAR. We evaluate four categories of SSL algorithms using three publicly available CSI HAR datasets, each encompassing different tasks and environmental settings. To ensure relevance to real-world applications, we design performance metrics that align with specific requirements. Furthermore, our experimental findings uncover several limitations and blind spots in existing work, highlighting the barriers that need to be addressed before SSL can be effectively deployed in real-world WiFi-based HAR applications. Our results also serve as a practical guideline for industry practitioners and provide valuable insights for future research endeavors in this field.
RFID-Assisted Indoor Localization Using Hybrid Wireless Data Fusion
Authors: Abouzar Ghavami, Ali Abedi
Date: 2023-07-28 00:00:00
Tasks: Indoor Localization

Wireless localization is essential for tracking objects in indoor environments. Internet of Things (IoT) enables localization through its diverse wireless communication protocols. In this paper, a hybrid section-based indoor localization method using a developed Radio Frequency Identification (RFID) tracking device and multiple IoT wireless technologies is proposed. In order to reduce the cost of the RFID tags, the tags are installed only on the borders of each section. The RFID tracking device identifies the section, and the proposed wireless hybrid method finds the location of the object inside the section. The proposed hybrid method is analytically driven by linear location estimates obtained from different IoT wireless technologies. The experimental results using developed RFID tracking device and RSSI-based localization for Bluetooth, WiFi and ZigBee technologies verifies the analytical results.
Discrete-Time Adaptive State Tracking Control Schemes Using Gradient Algorithms
Authors: Gang Tao
Date: 2023-08-04 00:00:00

This paper conducts a comprehensive study of a classical adaptive control problem: adaptive control of a state-space plant model: $\dot{x}(t) = A x(t) + B u(t)$ in continuous time, or $x(t+1) = A x(t) + B u(t)$ in discrete time, for state tracking of a chosen stable reference model system: $\dot{x}_m(t) = A_m x_m(t) + B_m r(t)$ in continuous time, or $x_m(t+1) = A_m x_m(t) + B_m r(t)$ in discrete time. Adaptive state tracking control schemes for continuous-time systems have been reported in the literature, using a Lyapunov design and analysis method which has not been successfully applied to discrete-time systems, so that the discrete-time adaptive state tracking problem has remained to be open. In this paper, new adaptive state tracking control schemes are developed for discrete-time systems, using a gradient method for the design of adaptive laws for updating the controller parameters. Both direct and indirect adaptive designs are presented, which have the standard and desired adaptive law properties. Such a new gradient algorithm based framework is also developed for adaptive state tracking control of continuous-time systems, as compared with the Lyapunov method based framework.
Optimal Sizing of On-site Renewable Resources for Offshore Microgrids
Authors: Ann Mary Toms, Xingpeng Li, Kaushik Rajashekara
Date: 2023-08-04 00:00:00

The offshore oil and natural gas platforms, mostly powered by diesel or gas generators, consume approximately 16TWh of electricity worldwide per year, which emits large amount of CO2. To limit their contribution to climate change, a proposed solution is to replace the traditional fossil fuel based energy resources with offshore clean energy. One of the main challenges in designing such a system is to ensure that energy demand is met while minimizing cost and reducing environmental impact. To address this challenge, several strategies including microgrid systems consisting of offshore wind turbines, wave energy converters, tidal energy converters, floating photovoltaic systems and battery energy storage systems are being proposed. In this paper, cost optimization for sizing these renewable energy sources is investigated. A cost optimization renewable sizing (CORS) model is proposed to optimize the sizes of the generation and storage resources. The proposed CORS model considers the variability of the power outputs of various renewable energy sources and load, as well as the cost of different generation technologies and the energy storage system. Simulations conducted on three test systems show the proposed resource sizing method significantly reduces the total lifetime cost of energy while maintaining a high level of reliability and sustainability.
Communication-Efficient Decentralized Multi-Agent Reinforcement Learning for Cooperative Adaptive Cruise Control
Authors: Dong Chen, Kaixiang Zhang, Yongqiang Wang, Xunyuan Yin, Zhaojian Li, Dimitar Filev
Date: 2023-08-04 00:00:00
Tasks: Autonomous Vehicles, Multi-agent Reinforcement Learning, Quantization

Connected and autonomous vehicles (CAVs) promise next-gen transportation systems with enhanced safety, energy efficiency, and sustainability. One typical control strategy for CAVs is the so-called cooperative adaptive cruise control (CACC) where vehicles drive in platoons and cooperate to achieve safe and efficient transportation. In this study, we formulate CACC as a multi-agent reinforcement learning (MARL) problem. Diverging from existing MARL methods that use centralized training and decentralized execution which require not only a centralized communication mechanism but also dense inter-agent communication during training and online adaptation, we propose a fully decentralized MARL framework for enhanced efficiency and scalability. In addition, a quantization-based communication scheme is proposed to reduce the communication overhead without significantly degrading the control performance. This is achieved by employing randomized rounding numbers to quantize each piece of communicated information and only communicating non-zero components after quantization. Extensive experimentation in two distinct CACC settings reveals that the proposed MARL framework consistently achieves superior performance over several contemporary benchmarks in terms of both communication efficiency and control efficacy. In the appendix, we show that our proposed framework's applicability extends beyond CACC, showing promise for broader intelligent transportation systems with intricate action and state spaces.
Novel Online-Offline MA2C-DDPG for Efficient Spectrum Allocation and Trajectory Optimization in Dynamic Spectrum Sharing UAV Networks
Authors: Rui Ding, Fuhui Zhou, Yuben Qu, Chao Dong, Qihui Wu, Tony Q. S. Quek
Date: 2023-08-04 00:00:00

Unmanned aerial vehicle (UAV) communication is of crucial importance for diverse practical applications. However, it is susceptible to the severe spectrum scarcity problem and interference since it operates in the unlicensed spectrum band. In order to tackle those issues, a dynamic spectrum sharing network is considered with the anti-jamming technique. Moreover, an intelligent spectrum allocation and trajectory optimization scheme is proposed to adapt to diverse jamming models by exploiting our designed novel online-offline multi-agent actor-critic and deep deterministic policy-gradient framework. Simulation results demonstrate the high efficiency of our proposed framework. It is also shown that our proposed scheme achieves the largest transmission rate among all benchmark schemes.
An Add-on Model Predictive Control Strategy for the Energy Management of Hybrid Electric Tractors
Authors: Stefano Radrizzani, Giulio Panzani, Luca Trezza, Solomon Pizzocaro, Sergio M. Savaresi
Date: 2023-08-04 00:00:00
Tasks: energy management, Management, Model Predictive Control

The hybridization process has recently touched also the world of agricultural vehicles. Within this context, we develop an Energy Management Strategy (EMS) aiming at optimizing fuel consumption, while maintaining the battery state of charge. A typical feature of agricultural machines is that their internal combustion engine is speed controlled, tracking the reference requested by the driver. In view of avoiding any modification on this original control loop, an add-on EMS strategy is proposed. In particular, we employ a multi-objective Model Predictive Control (MPC), taking into account the fuel consumption minimization and the speed tracking requirement, including the engine speed controller in the predictive model. The proposed MPC is tested in an experimentally-validated simulation environment, representative of an orchard vineyard tractor.
Decoupling control parameter method to study the coupling characteristics of subsystems in the feed system
Authors: Dongsheng Zhang, Xuesong Wang, Tingting Zhang
Date: 2023-08-04 00:00:00

When developing high-speed and high-precision CNC machine tools, subsystem coupling effects must be considered while designing the feed system to maximize its dynamic performance. Currently, the influence of changes in control parameters on the matching characteristics of each subsystem was not yet considered when studying the coupling relationship between subsystems. Therefore, it is difficult to define the law of action between subsystems under the interference of control parameters. Hence, a new method was proposed in this paper aiming to isolate the disturbance of control parameters and to highlight the actions between electromechanical subsystems. This was achieved by optimizing the servo control parameters for each configuration of electromechanical parameters, ensuring that the feed system performance is optimal for the observed configuration. This approach eliminated the influence of the control subsystem on the electromechanical coupling relationship. The approach effectiveness was verified via the integrated model of the feed system. As such, this paper provides a reliable method to further study the coupling mechanism of subsystems, revealing the mechanism behind the dynamic design of feed systems.
Transformer-Based Denoising of Mechanical Vibration Signals
Authors: Han Chen, Yang Yu, Pengtao Li
Date: 2023-08-04 00:00:00
Tasks: Denoising

Mechanical vibration signal denoising is a pivotal task in various industrial applications, including system health monitoring and failure prediction. This paper introduces a novel deep learning transformer-based architecture specifically tailored for denoising mechanical vibration signals. The model leverages a Multi-Head Attention layer with 8 heads, processing input sequences of length 128, embedded into a 64-dimensional space. The architecture also incorporates Feed-Forward Neural Networks, Layer Normalization, and Residual Connections, resulting in enhanced recognition and extraction of essential features. Through a training process guided by the Mean Squared Error loss function and optimized using the Adam optimizer, the model demonstrates remarkable effectiveness in filtering out noise while preserving critical information related to mechanical vibrations. The specific design and choice of parameters offer a robust method adaptable to the complex nature of mechanical systems, with promising applications in industrial monitoring and maintenance. This work lays the groundwork for future exploration and optimization in the field of mechanical signal analysis and presents a significant step towards advanced and intelligent mechanical system diagnostics.
Sub-Nyquist Sampling OFDM Radar
Authors: Kawon Han, SeongHyeon Kang, Songcheol Hong
Date: 2023-08-03 00:00:00

In this paper, we propose a sub-Nyquist sampling (SNS) orthogonal frequency-division multiplexing (OFDM) radar system capable of reducing the analog-to-digital converter (ADC) sampling rate in OFDM radar without any additional manipulations of its hardware and waveform. To this end, the proposed system utilizes the ADC sampling rate of B/L to sample the received baseband signal with a bandwidth of B, where L is a positive proper divisor of the number of subcarriers. This divides the baseband signal into L sub-bands, folding into a sub-Nyquist frequency band due to aliasing. By leveraging known modulation symbols of the transmitted signal, the folded signal can be unfolded to the full-band signal. This allows an estimation of target ranges with the range resolution of the full signal bandwidth B without the degradation of the maximum unambiguous range. During the signal-unfolding process, the signals from other sub-bands remain as symbol-mismatch noise (SMN), which significantly degrades the signal-to-noise ratio (SNR) of the detected targets. It also causes weaker targets to be submerged under the noise in range profiles. To resolve this, a symbol-mismatch noise cancellation (SMNC) technique is also proposed, which reconstructs the interfering signals from the other sub-bands using the detected targets and subtracts them from the unfolded signal. As a result, the proposed sub-Nyquist sampling OFDM radar and corresponding signal processing technique enable a reduction in the ADC sampling rate by the ratio of L while incurring only a 10 log10 L increase in the noise due to noise folding. This is validated through simulations and measurements with various sub-sampling ratios.
Optimal Dynamic Reconfiguration of Distribution Networks
Authors: Rida Fatima, Hassan Zahid Butt, Xingpeng Li
Date: 2023-08-03 00:00:00

The aim of distribution networks is to meet their local area power demand with maximum reliability. As the electricity consumption tends to increase every year, limited line thermal capacity can lead to network congestion. Continuous development and upgradation of the distribution network is thus required to meet the energy demand, which poses a significant increase in cost. The objective of this research is to analyze distribution network topologies and introduce a topology reconfiguration scheme based on the cost and demand of electricity. Traditional electrical distribution networks are static and inefficient. To make the network active, an optimal dynamic network topology reconfiguration (DNTR) is proposed to control line switching and reconnect some loads to different substations such that the cost of electricity can be minimized. The proposed DNTR strategy was tested on a synthetic radial distribution network with three substations each connecting to an IEEE 13-bus system. Simulation results demonstrated significant cost saving in daily operations of this distribution system.
A Taxonomy of Adaptive Traffic Signal Control
Authors: Andalib Shams, A. M. Tahsin Emtenan, Christopher M. Day
Date: 2023-08-03 00:00:00
Tasks: Decision Making, Diversity, Traffic Signal Control

Research on adaptive traffic signal control (ATSC) extends back to at least the 1960s, and many ATSC methods have been proposed over the years. This paper provides a review of this research and proposes a taxonomy for organizing it, accompanied by a consistent vocabulary for discussing the control concepts. We begin from the well-established concept of control generations. Next, we classify the ATSC methods according to their topographic structure (local-only, system/hierarchical), time resolution of decision-making (continuous versus planning-horizon), type of decision (rule-based or optimization), objective function, cyclic/acyclic nature,and additional subcategories relevant to certain "families" of methods. These various elements of system control are organized into a taxonomy of ATSC to help future researchers understand the wide diversity of algorithmic approaches to the signal control problem that have been proposed to date, and which can be updated or expanded to incorporate future research.
Experiment-based deep learning approach for power allocation with a programmable metasurface
Authors: Jingxin Zhang, Jiawei Xi, Peixing Li, Ray C. C. Cheung, Alex M. H. Wong, Jensen Li
Date: 2023-07-26 00:00:00
Tasks: Deep Learning

Deep learning, as a highly efficient method for metasurface inverse design, commonly use simulation data to train deep neural networks (DNNs) that can map desired functionalities to proper metasurface designs. However, the assumptions and simplifications made in the simulation model may not reflect the actual behavior of a complex system, leading to suboptimal performance of the DNNs in practical scenarios. To address this issue, we propose an experiment-based deep learning approach for metasurface inverse design and demonstrate its effectiveness for power allocation in complex environments with obstacles. Enabled by the tunability of a programmable metasurface, large sets of experimental data in various configurations can be collected for DNN training. The DNN trained by experimental data can inherently incorporate complex factors and can adapt to changed environments through its on-site data-collecting and fast-retraining capability. The proposed experiment-based DNN holds the potential for intelligent and energy-efficient wireless communication in complex indoor environments.
Experimentally realized physical-model-based wave control in metasurface-programmable complex media
Authors: Jérôme Sol, Hugo Prod'homme, Luc Le Magoarou, Philipp del Hougne
Date: 2023-07-17 00:00:00

The reconfigurability of radio environments with programmable metasurfaces is considered a key feature of next-generation wireless networks. Identifying suitable metasurface configurations for desired wireless functionalities requires a precise setting-specific understanding of the intricate impact of the metasurface configuration on the wireless channels. Yet, to date, the relevant short and long-range correlations between the meta-atoms due to proximity and reverberation are largely ignored rather than precisely captured. Here, we experimentally demonstrate that a compact model derived from first physical principles can precisely predict how wireless channels in complex scattering environments depend on the programmable-metasurface configuration. The model is calibrated using a very small random subset of all possible metasurface configurations and without knowing the setup's geometry. Our approach achieves two orders of magnitude higher precision than a deep learning-based digital-twin benchmark while involving hundred times fewer parameters. Strikingly, when only phaseless calibration data is available, our model can nonetheless retrieve the precise phase relations of the scattering matrix as well as their dependencies on the metasurface configuration. Thereby, we achieve coherent wave control (focusing or enhancing absorption) and phase-shift-keying backscatter communications without ever having measured phase information. Finally, our model is also capable of retrieving the essential properties of scattering coefficients for which no calibration data was ever provided. These unique generalization capabilities of our pure-physics model significantly alleviate the measurement complexity. Our approach is also directly relevant to dynamic metasurface antennas, microwave-based signal processors as well as emerging in situ reconfigurable nanophotonic, optical and room-acoustical systems.
Maximum-likelihood estimation in ptychography in the presence of Poisson-Gaussian noise statistics
Authors: Jacob Seifert, Yifeng Shao, Rens van Dam, Dorian Bouchet, Tristan van Leeuwen, Allard P. Mosk
Date: 2023-08-03 00:00:00
Tasks: Image Reconstruction

Optical measurements often exhibit mixed Poisson-Gaussian noise statistics, which hampers image quality, particularly under low signal-to-noise ratio (SNR) conditions. Computational imaging falls short in such situations when solely Poissonian noise statistics are assumed. In response to this challenge, we define a loss function that explicitly incorporates this mixed noise nature. By using maximum-likelihood estimation, we devise a practical method to account for camera readout noise in gradient-based ptychography optimization. Our results, based on both experimental and numerical data, demonstrate that this approach outperforms the conventional one, enabling enhanced image reconstruction quality under challenging noise conditions through a straightforward methodological adjustment.
Numerical Uncertainty of Convolutional Neural Networks Inference for Structural Brain MRI Analysis
Authors: Inés Gonzalez Pepe, Vinuyan Sivakolunthu, Hae Lang Park, Yohan Chatelain, Tristan Glatard
Date: 2023-08-03 00:00:00
Tasks: Brain Segmentation, Segmentation

This paper investigates the numerical uncertainty of Convolutional Neural Networks (CNNs) inference for structural brain MRI analysis. It applies Random Rounding -- a stochastic arithmetic technique -- to CNN models employed in non-linear registration (SynthMorph) and whole-brain segmentation (FastSurfer), and compares the resulting numerical uncertainty to the one measured in a reference image-processing pipeline (FreeSurfer recon-all). Results obtained on 32 representative subjects show that CNN predictions are substantially more accurate numerically than traditional image-processing results (non-linear registration: 19 vs 13 significant bits on average; whole-brain segmentation: 0.99 vs 0.92 S{\o}rensen-Dice score on average), which suggests a better reproducibility of CNN results across execution environments.