A wide variety of data can be represented using third-order tensors. Applications of these tensors include chemometrics, psychometrics, and image/video processing. However, traditional data-driven frameworks are not naturally equipped to process tensors without first unfolding or flattening the data, which can result in a loss of crucial higher-order structural information. In this letter, we introduce a novel framework for data-driven analysis of T-product-based dynamical systems (TPDSs), where the system evolution is governed by the T-product between a third-order dynamic tensor and a third-order state tensor. In particular, we examine the data informativity of TPDSs concerning system identification, stability, controllability, and stabilizability and illustrate significant computational improvements over unfolding-based approaches by leveraging the unique properties of the T-product. The effectiveness of our framework is demonstrated through both synthetic and real-world examples.
{"title":"Data-Driven Analysis of T-Product-Based Dynamical Systems","authors":"Xin Mao;Anqi Dong;Ziqin He;Yidan Mei;Shenghan Mei;Ren Wang;Can Chen","doi":"10.1109/LCSYS.2025.3532470","DOIUrl":"https://doi.org/10.1109/LCSYS.2025.3532470","url":null,"abstract":"A wide variety of data can be represented using third-order tensors. Applications of these tensors include chemometrics, psychometrics, and image/video processing. However, traditional data-driven frameworks are not naturally equipped to process tensors without first unfolding or flattening the data, which can result in a loss of crucial higher-order structural information. In this letter, we introduce a novel framework for data-driven analysis of T-product-based dynamical systems (TPDSs), where the system evolution is governed by the T-product between a third-order dynamic tensor and a third-order state tensor. In particular, we examine the data informativity of TPDSs concerning system identification, stability, controllability, and stabilizability and illustrate significant computational improvements over unfolding-based approaches by leveraging the unique properties of the T-product. The effectiveness of our framework is demonstrated through both synthetic and real-world examples.","PeriodicalId":37235,"journal":{"name":"IEEE Control Systems Letters","volume":"8 ","pages":"3356-3361"},"PeriodicalIF":2.4,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143184171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-17DOI: 10.1109/LCSYS.2025.3531039
Nguyen Huu Sau;Mai Viet Thuan
This letter investigates stabilizing discrete-time systems with delays using an event-triggered control (ETC) approach. Novel event-triggering conditions are proposed to ensure system positivity and stability thresholds. Sufficient conditions are derived to guarantee that the closed-loop system remains positive and exponentially stable, with criteria easily verifiable in MATLAB. We also address the nontriviality of the sequence of event instants to ensure the practical effectiveness of the proposed method. Two numerical examples are presented to illustrate the effectiveness of the proposed method.
{"title":"Novel Sufficient Conditions for Stabilization of Linear Positive Discrete-Time Systems Using Event-Triggered Control","authors":"Nguyen Huu Sau;Mai Viet Thuan","doi":"10.1109/LCSYS.2025.3531039","DOIUrl":"https://doi.org/10.1109/LCSYS.2025.3531039","url":null,"abstract":"This letter investigates stabilizing discrete-time systems with delays using an event-triggered control (ETC) approach. Novel event-triggering conditions are proposed to ensure system positivity and stability thresholds. Sufficient conditions are derived to guarantee that the closed-loop system remains positive and exponentially stable, with criteria easily verifiable in MATLAB. We also address the nontriviality of the sequence of event instants to ensure the practical effectiveness of the proposed method. Two numerical examples are presented to illustrate the effectiveness of the proposed method.","PeriodicalId":37235,"journal":{"name":"IEEE Control Systems Letters","volume":"8 ","pages":"3345-3349"},"PeriodicalIF":2.4,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143184228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-17DOI: 10.1109/LCSYS.2025.3531212
Wenrui Shi;Christodoulos Keliris;Mingzhe Hou;Marios M. Polycarpou
This letter proposes a class of modified continuous-time (CT) and discrete-time (DT) finite-time convergence (FTC) estimators based on the dynamic regressor extension and mixing (DREM) method, additionally the same two estimators with alertness preservation and, finally CT and DT prescribed-time convergence (PTC) estimators. In contrast to previously designed FTC estimators based on the DREM method, by introducing the integration and the summation operations, the proposed ones possess the following features: (i) the convergence rate is improved; (ii) the FTC property can be maintained even for a weaker excitation signal. Additionally, the proposed PTC estimators ensure that under certain conditions the estimate converges to the unknown parameter in the prescribed time.
{"title":"Modified Finite-Time and Prescribed-Time Convergence Parameter Estimators via the DREM Method","authors":"Wenrui Shi;Christodoulos Keliris;Mingzhe Hou;Marios M. Polycarpou","doi":"10.1109/LCSYS.2025.3531212","DOIUrl":"https://doi.org/10.1109/LCSYS.2025.3531212","url":null,"abstract":"This letter proposes a class of modified continuous-time (CT) and discrete-time (DT) finite-time convergence (FTC) estimators based on the dynamic regressor extension and mixing (DREM) method, additionally the same two estimators with alertness preservation and, finally CT and DT prescribed-time convergence (PTC) estimators. In contrast to previously designed FTC estimators based on the DREM method, by introducing the integration and the summation operations, the proposed ones possess the following features: (i) the convergence rate is improved; (ii) the FTC property can be maintained even for a weaker excitation signal. Additionally, the proposed PTC estimators ensure that under certain conditions the estimate converges to the unknown parameter in the prescribed time.","PeriodicalId":37235,"journal":{"name":"IEEE Control Systems Letters","volume":"8 ","pages":"3350-3355"},"PeriodicalIF":2.4,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143184230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-16DOI: 10.1109/LCSYS.2025.3530636
Chenyan Zhu;Sandip Roy
Refined bounds are obtained for the eigenvalues of the controllability Gramian for a linear system with a Hurwitz, symmetric state matrix. The new bounds are phrased in terms of partial condition numbers (ratios of intermediate eigenvalues) of the state matrix. The bounds are found to compare favorably with existing results for several examples, particularly in cases where the system has time-scale separations or multiple eigenvalues in narrow bands.
{"title":"Refined Eigenvalue Decay Bounds for Controllability Gramians of Sparsely-Actuated Symmetric LTI Systems","authors":"Chenyan Zhu;Sandip Roy","doi":"10.1109/LCSYS.2025.3530636","DOIUrl":"https://doi.org/10.1109/LCSYS.2025.3530636","url":null,"abstract":"Refined bounds are obtained for the eigenvalues of the controllability Gramian for a linear system with a Hurwitz, symmetric state matrix. The new bounds are phrased in terms of partial condition numbers (ratios of intermediate eigenvalues) of the state matrix. The bounds are found to compare favorably with existing results for several examples, particularly in cases where the system has time-scale separations or multiple eigenvalues in narrow bands.","PeriodicalId":37235,"journal":{"name":"IEEE Control Systems Letters","volume":"8 ","pages":"3362-3367"},"PeriodicalIF":2.4,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143184172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-01-02DOI: 10.1109/LCSYS.2024.3525096
Saba Zerefa;Zhaolin Ren;Haitong Ma;Na Li
In Bayesian optimization, a black-box function is maximized via the use of a surrogate model. We apply distributed Thompson sampling, using a Gaussian process as a surrogate model, to approach the multi-agent Bayesian optimization problem. In our distributed Thompson sampling implementation, each agent receives sampled points from neighbors, where the communication network is encoded in a graph; each agent utilizes their own Gaussian process to model the objective function. We demonstrate theoretical bounds on Bayesian average regret and Bayesian simple regret, where the bound depends on the structure of the communication graph. Unlike in batch Bayesian optimization, this bound is applicable in cases where the communication graph amongst agents is constrained. When compared to sequential single-agent Thompson sampling, our bound guarantees faster convergence with respect to time as long as the communication graph is connected. We confirm the efficacy of our algorithm with numerical simulations on traditional optimization test functions, demonstrating the significance of graph connectivity on improving regret convergence.
{"title":"Distributed Thompson Sampling Under Constrained Communication","authors":"Saba Zerefa;Zhaolin Ren;Haitong Ma;Na Li","doi":"10.1109/LCSYS.2024.3525096","DOIUrl":"https://doi.org/10.1109/LCSYS.2024.3525096","url":null,"abstract":"In Bayesian optimization, a black-box function is maximized via the use of a surrogate model. We apply distributed Thompson sampling, using a Gaussian process as a surrogate model, to approach the multi-agent Bayesian optimization problem. In our distributed Thompson sampling implementation, each agent receives sampled points from neighbors, where the communication network is encoded in a graph; each agent utilizes their own Gaussian process to model the objective function. We demonstrate theoretical bounds on Bayesian average regret and Bayesian simple regret, where the bound depends on the structure of the communication graph. Unlike in batch Bayesian optimization, this bound is applicable in cases where the communication graph amongst agents is constrained. When compared to sequential single-agent Thompson sampling, our bound guarantees faster convergence with respect to time as long as the communication graph is connected. We confirm the efficacy of our algorithm with numerical simulations on traditional optimization test functions, demonstrating the significance of graph connectivity on improving regret convergence.","PeriodicalId":37235,"journal":{"name":"IEEE Control Systems Letters","volume":"8 ","pages":"3309-3314"},"PeriodicalIF":2.4,"publicationDate":"2025-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143184271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-31DOI: 10.1109/LCSYS.2024.3524369
Zahra Marvi;Francesco Bullo;Andrew G. Alleyne
In this letter, we address the critical trade-off between safety and performance in control systems by establishing the contractivity of a class of nonlinear systems driven by control barrier function (CBF)-based online feedback optimization. First, we derive a closed-form solution for the control system driven by a CBF-based controller with vector-valued safety constraints. Next, we introduce sufficient design conditions based on the properties of a baseline controller and CBF parameters to ensure both safety and contractivity of the closed-loop system. Under these conditions, we demonstrate the existence of an exponentially stable equilibrium within the safe set and provide an explicit term for the rate of convergence. Building upon these results, we propose a feedback motion planning algorithm that guarantees a global region of attraction within non-convex search areas through a tree of contractive controllers. The contractive nature of our approach ensures robustness against perturbations, making it suitable for dynamic and uncertain environments.
{"title":"Robust and Exponential Stability in Barrier-Certified Systems via Contracting Piecewise Smooth Dynamics","authors":"Zahra Marvi;Francesco Bullo;Andrew G. Alleyne","doi":"10.1109/LCSYS.2024.3524369","DOIUrl":"https://doi.org/10.1109/LCSYS.2024.3524369","url":null,"abstract":"In this letter, we address the critical trade-off between safety and performance in control systems by establishing the contractivity of a class of nonlinear systems driven by control barrier function (CBF)-based online feedback optimization. First, we derive a closed-form solution for the control system driven by a CBF-based controller with vector-valued safety constraints. Next, we introduce sufficient design conditions based on the properties of a baseline controller and CBF parameters to ensure both safety and contractivity of the closed-loop system. Under these conditions, we demonstrate the existence of an exponentially stable equilibrium within the safe set and provide an explicit term for the rate of convergence. Building upon these results, we propose a feedback motion planning algorithm that guarantees a global region of attraction within non-convex search areas through a tree of contractive controllers. The contractive nature of our approach ensures robustness against perturbations, making it suitable for dynamic and uncertain environments.","PeriodicalId":37235,"journal":{"name":"IEEE Control Systems Letters","volume":"8 ","pages":"3279-3284"},"PeriodicalIF":2.4,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142938113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-30DOI: 10.1109/LCSYS.2024.3524063
Hang Gu;Chao Shen
Image-based visual servoing (IBVS) applications for autonomous underwater vehicles (AUVs) face significant challenges, including frequent recalibration and lack of constraint handling ability. This letter introduces a novel nonlinear model predictive control (NMPC) approach that integrates the Broyden method for uncalibrated IBVS and incorporates the min-max strategy to tolerate the errors in Jacobian matrix estimation. Our proposed min-max NMPC-IBVS framework estimates the Jacobian matrix online, allowing for continuous adaptation to the underwater environment without the need for prior calibration. This approach significantly enhances computational efficiency and robust control performance, enabling real-time uncalibrated applications. A rigorous proof of recursive feasibility is provided in this letter, ensuring that our NMPC-IBVS method consistently finds feasible optimal solutions that satisfy all constraints over time. Simulation results show that the proposed method is able to respect all design constraints in the AUV IBVS control and achieve robust stability with boosted computational efficiency.
{"title":"Robust NMPC for Uncalibrated IBVS Control of AUVs","authors":"Hang Gu;Chao Shen","doi":"10.1109/LCSYS.2024.3524063","DOIUrl":"https://doi.org/10.1109/LCSYS.2024.3524063","url":null,"abstract":"Image-based visual servoing (IBVS) applications for autonomous underwater vehicles (AUVs) face significant challenges, including frequent recalibration and lack of constraint handling ability. This letter introduces a novel nonlinear model predictive control (NMPC) approach that integrates the Broyden method for uncalibrated IBVS and incorporates the min-max strategy to tolerate the errors in Jacobian matrix estimation. Our proposed min-max NMPC-IBVS framework estimates the Jacobian matrix online, allowing for continuous adaptation to the underwater environment without the need for prior calibration. This approach significantly enhances computational efficiency and robust control performance, enabling real-time uncalibrated applications. A rigorous proof of recursive feasibility is provided in this letter, ensuring that our NMPC-IBVS method consistently finds feasible optimal solutions that satisfy all constraints over time. Simulation results show that the proposed method is able to respect all design constraints in the AUV IBVS control and achieve robust stability with boosted computational efficiency.","PeriodicalId":37235,"journal":{"name":"IEEE Control Systems Letters","volume":"8 ","pages":"3237-3242"},"PeriodicalIF":2.4,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142938059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-30DOI: 10.1109/LCSYS.2024.3524056
Jingru Zhu;Cheng Zhao
This letter studies control problems for a class of multi-input multi-output (MIMO) strongly coupled nonlinear uncertain systems with mixed relative degrees one and two. We will design an uncoupled PID controller, where each component of the input vector is determined only by a component of the system output regulation error. Under some suitable conditions on the system nonlinear uncertain functions, we will show that the proposed controller can ensure global stability of the closed-loop system while guaranteeing that the output regulation error converges to zero at an exponential rate. We will also demonstrate that the PID parameters can be chosen from an open and unbounded set constructed based on some prior knowledge regarding the nonlinear functions of the system, and that the designed PID controller exhibits two-sided robustness in terms of the uncertain system structure and the selection of controller parameters. A simulation will be provided to verify the theoretical findings.
{"title":"PID Control of MIMO Nonlinear Uncertain Systems With Low Relative Degrees","authors":"Jingru Zhu;Cheng Zhao","doi":"10.1109/LCSYS.2024.3524056","DOIUrl":"https://doi.org/10.1109/LCSYS.2024.3524056","url":null,"abstract":"This letter studies control problems for a class of multi-input multi-output (MIMO) strongly coupled nonlinear uncertain systems with mixed relative degrees one and two. We will design an uncoupled PID controller, where each component of the input vector is determined only by a component of the system output regulation error. Under some suitable conditions on the system nonlinear uncertain functions, we will show that the proposed controller can ensure global stability of the closed-loop system while guaranteeing that the output regulation error converges to zero at an exponential rate. We will also demonstrate that the PID parameters can be chosen from an open and unbounded set constructed based on some prior knowledge regarding the nonlinear functions of the system, and that the designed PID controller exhibits two-sided robustness in terms of the uncertain system structure and the selection of controller parameters. A simulation will be provided to verify the theoretical findings.","PeriodicalId":37235,"journal":{"name":"IEEE Control Systems Letters","volume":"8 ","pages":"3213-3218"},"PeriodicalIF":2.4,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142938056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-27DOI: 10.1109/LCSYS.2024.3523432
Nguyen Thi Lien;Le Van Hien;Nguyen Nhu Thang
This note is concerned with a class of homogeneous cooperative systems with bounded time-varying delays described by the Caputo fractional derivative. We focus on the existence, uniqueness, and Mittag-Leffler stability of positive solutions when the associated vector fields are homogeneous with a degree less than or equal to one. Specifically, the solvability is first exploited through the fixed point theory, leveraging the homogeneity of nonlinear terms. Then, a delay-independent condition for Mittag-Leffler stability is established by utilizing the properties of Mittag-Leffler functions and the comparison principle. Finally, the theoretical results are validated by a given numerical example.
{"title":"Mittag-Leffler Stability of Homogeneous Fractional-Order Systems With Delay","authors":"Nguyen Thi Lien;Le Van Hien;Nguyen Nhu Thang","doi":"10.1109/LCSYS.2024.3523432","DOIUrl":"https://doi.org/10.1109/LCSYS.2024.3523432","url":null,"abstract":"This note is concerned with a class of homogeneous cooperative systems with bounded time-varying delays described by the Caputo fractional derivative. We focus on the existence, uniqueness, and Mittag-Leffler stability of positive solutions when the associated vector fields are homogeneous with a degree less than or equal to one. Specifically, the solvability is first exploited through the fixed point theory, leveraging the homogeneity of nonlinear terms. Then, a delay-independent condition for Mittag-Leffler stability is established by utilizing the properties of Mittag-Leffler functions and the comparison principle. Finally, the theoretical results are validated by a given numerical example.","PeriodicalId":37235,"journal":{"name":"IEEE Control Systems Letters","volume":"8 ","pages":"3243-3248"},"PeriodicalIF":2.4,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142938066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-27DOI: 10.1109/LCSYS.2024.3523845
Charlotte Cathcart;Ian Xul Belaustegui;Alessio Franci;Naomi Ehrich Leonard
We present, analyze, and illustrate a first-of-its-kind model of two-dimensional excitable (spiking) dynamics for decision-making over two options. The model, Spiking Nonlinear Opinion Dynamics (S-NOD), provides superior agility, characterized by fast, flexible, and adaptive response to rapid and unpredictable changes in context, environment, or information received about available options. S-NOD derives through the introduction of a single extra term to the previously presented Nonlinear Opinion Dynamics (NOD) for fast and flexible multi-agent decision-making behavior. The extra term is inspired by the fast-positive, slow-negative mixed-feedback structure of excitable systems. The agile behaviors brought about by the new excitable nature of decision-making driven by S-NOD are analyzed in a general setting and illustrated in an application to multi-robot navigation around human movers.
{"title":"Spiking Nonlinear Opinion Dynamics (S-NOD) for Agile Decision-Making","authors":"Charlotte Cathcart;Ian Xul Belaustegui;Alessio Franci;Naomi Ehrich Leonard","doi":"10.1109/LCSYS.2024.3523845","DOIUrl":"https://doi.org/10.1109/LCSYS.2024.3523845","url":null,"abstract":"We present, analyze, and illustrate a first-of-its-kind model of two-dimensional excitable (spiking) dynamics for decision-making over two options. The model, Spiking Nonlinear Opinion Dynamics (S-NOD), provides superior agility, characterized by fast, flexible, and adaptive response to rapid and unpredictable changes in context, environment, or information received about available options. S-NOD derives through the introduction of a single extra term to the previously presented Nonlinear Opinion Dynamics (NOD) for fast and flexible multi-agent decision-making behavior. The extra term is inspired by the fast-positive, slow-negative mixed-feedback structure of excitable systems. The agile behaviors brought about by the new excitable nature of decision-making driven by S-NOD are analyzed in a general setting and illustrated in an application to multi-robot navigation around human movers.","PeriodicalId":37235,"journal":{"name":"IEEE Control Systems Letters","volume":"8 ","pages":"3267-3272"},"PeriodicalIF":2.4,"publicationDate":"2024-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142938063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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