IET Control Theory and Applications最新文献

{"title":"Disturbance Observer Based Adaptive Control Scheme for Synchronization of Fractional Order Chaotic Systems With Input Delay","authors":"Mehran Derakhshannia,&nbsp;Seyyed Sajjad Moosapour,&nbsp;Saleh Mobayen","doi":"10.1049/cth2.70037","DOIUrl":"10.1049/cth2.70037","url":null,"abstract":"<p>In recent years, considerable attention has been attracted to the synchronization of chaotic systems due to their important applications. However, fractional order non-linear chaotic systems face critical challenges, particularly from input delays and external disturbances in practical applications. In this paper, a robust synchronization method based on state prediction is introduced to address these challenges. First, a novel adaptive disturbance observer for fractional order systems is proposed, ensuring that disturbance estimation is achieved within an arbitrary time. The effects of disturbances are mitigated by this observer, which plays a crucial role in synchronization scheme design. Second, an arbitrary time exponential sliding mode controller that integrates state prediction and the disturbance observer is presented to handle input delay in fractional chaotic systems subjected to external disturbances. Third, a control scheme incorporating state prediction and sliding mode control is developed to address chaos synchronization for fractional systems with time varying input delays and disturbances. Additionally, an upper bound for input delay is established, demonstrating that if the delay remains below this threshold, the synchronization error is constrained. The efficacy and practical applicability of the proposed synchronization scheme are confirmed through simulation studies and experimental validation on a real-time Speedgoat machine.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":"19 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.70037","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144492933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Model Predictive Control of Vehicle Stability Using Differential Driving Torque","authors":"Jianjian Liu,&nbsp;Haolun Xu,&nbsp;Hongyi Zhu,&nbsp;Qian Zhu,&nbsp;Wenbin Han","doi":"10.1049/cth2.70044","DOIUrl":"10.1049/cth2.70044","url":null,"abstract":"&lt;p&gt;Electric vehicles (EVs) with distributed drive configurations demonstrate improved energy storage potential through battery-dominated systems, enabling independent torque allocation across individual wheels. This paper proposes a differential torque control framework for distributed-drive electric vehicles to enhance trajectory tracking accuracy and yaw stability during double-lane change maneuvers. A hierarchical control architecture with three layers are developed, integrating model predictive control with quadratic programming-based torque allocation to coordinate longitudinal velocity tracking and lateral path following. The lateral controller generates real-time differential torque commands (front-rear axle torque variation range: &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;±&lt;/mo&gt;\u0000 &lt;mn&gt;282.68&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$pm 282.68$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;–&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mo&gt;±&lt;/mo&gt;\u0000 &lt;mn&gt;409.42&lt;/mn&gt;\u0000 &lt;mspace&gt;&lt;/mspace&gt;\u0000 &lt;mi&gt;N&lt;/mi&gt;\u0000 &lt;mo&gt;·&lt;/mo&gt;\u0000 &lt;mi&gt;m&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$pm 409.42nobreakspace mathrm{Ncdot m}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) through a 3-DOF vehicle dynamic model, while the longitudinal controller maintains speed errors below 0.1 m/s through four-wheel independent torque regulation. Co-simulation on the CarSim-Simulink platform demonstrates the controller's adaptability to road friction coefficients (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;μ&lt;/mi&gt;\u0000 &lt;mo&gt;=&lt;/mo&gt;\u0000 &lt;mn&gt;0.5&lt;/mn&gt;\u0000 &lt;mo&gt;,&lt;/mo&gt;\u0000 &lt;mn&gt;0.8&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$mu =0.5,0.8$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;) and speed conditions (&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;u&lt;/mi&gt;\u0000 &lt;mo&gt;=&lt;/mo&gt;\u0000 &lt;mn&gt;40&lt;/mn&gt;\u0000 &lt;mo&gt;,&lt;/mo&gt;\u0000 &lt;mn&gt;50&lt;/mn&gt;\u0000 &lt;mo&gt;,&lt;/mo&gt;\u0000 &lt;mn&gt;60&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$u=40,50,60$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; km/h). The results achieve maximum yaw rate stabilization at 0.38 rad/s during high-speed maneuvers. Simulation results reveal that despite lateral deviation amplification (80–160 m trajectory segments) and torque oscillation divergence under &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;μ&lt;/mi&gt;\u0000 &lt;mo&gt;=&lt;/mo&gt;\u0000 &lt;mn&gt;0.5&lt;/mn&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$mu =0.5$&lt;/annotation&gt;\u0000 ","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":"19 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.70044","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144473178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sparse Identification of Nonlinear Dynamics-Based Model Predictive Control for Multirotor Collision Avoidance","authors":"Jayden Dongwoo Lee,&nbsp;Youngjae Kim,&nbsp;Yoonseong Kim,&nbsp;Hyochoong Bang","doi":"10.1049/cth2.70049","DOIUrl":"10.1049/cth2.70049","url":null,"abstract":"<p>This article proposes a data-driven model predictive control (MPC) method for multirotor collision avoidance, considering uncertainties and the unknown dynamics caused by a payload. To address this challenge, sparse identification of nonlinear dynamics (SINDy) is employed to derive the governing equations of the multirotor system. SINDy is capable of discovering the equations of target systems from limited data, under the assumption that a few dominant functions primarily characterize the system's behavior. In addition, a data collection framework that combines a baseline controller with MPC is proposed to generate diverse trajectories for model identification. A candidate function library, informed by prior knowledge of multirotor dynamics, along with a normalization technique, is utilized to enhance the accuracy of the SINDy-based model. Using data-driven model from SINDy, MPC is used to achieve accurate trajectory tracking while satisfying state and input constraints, including those for obstacle avoidance. Simulation results demonstrate that SINDy can successfully identify the governing equations of the multirotor system, accounting for mass parameter uncertainties and aerodynamic effects. Furthermore, the results confirm that the proposed method outperforms conventional MPC, which suffers from parameter uncertainty and an unknown aerodynamic model, in both obstacle avoidance and trajectory tracking performance.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":"19 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.70049","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144339138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Residue Matching: A Method to Determine Intersample Vibrations in Systems With State Feedback","authors":"Tamás Haba,&nbsp;Csaba Budai","doi":"10.1049/cth2.70051","DOIUrl":"10.1049/cth2.70051","url":null,"abstract":"<p>In this paper, we present a new method to determine the continuous-time response of sampled-data systems with uniform sampling, zero-order hold, and full-state feedback. In such systems, a continuous-time plant is controlled using a discrete-time control law. Traditionally, sampled-data systems are designed in discrete time, resulting in, given by the nature of this kind of modelling, unmodelled intersample behaviour. We show that the Laplace transform of the otherwise piecewise-continuous state response can be expressed in closed form that fully represents the intersample dynamics. A practical technique is also provided to decouple individual vibration components and reconstruct response functions in the time domain. The proposed approach is also able to capture intersample vibrations compared to common methods, which may lead to inaccurate results in specific cases. The presented new formulae are derived analytically and verified by simulations through numerical examples and experiments on a DC motor drive.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":"19 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.70051","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144314995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cooperative Adaptive Formation Fault-Tolerant Neural Control for Multiple Quadrotors With Full-State Constraints","authors":"Rui Dai,&nbsp;Yadong Yang,&nbsp;Jianye Gong,&nbsp;Qikun Shen","doi":"10.1049/cth2.70042","DOIUrl":"10.1049/cth2.70042","url":null,"abstract":"<p>This paper investigates the cooperative time-varying formation fault-tolerant control problem for multiple quadrotors with unknown actuator faults and full state constraints. In order to ensure the safety and operability of quadrotors in the confined flight environment, a novel transformed function is first introduced to convert the original quadrotor systems into unconstrained equivalent systems, which increases the flexibility of the controller design. Then, a distributed kinematic control protocol and fault-tolerant dynamic control protocol using the adaptive neural networks estimation technique are developed to guarantee the cooperative time-varying formation of multiple quadrotors subject to uncertain parameters. Meanwhile, the unknown actuator loss of effectiveness and bias faults are compensated and the state variables of position subsystem and attitude subsystem can be maintained within the designed performance constraint sets even when actuator faults occur. Via Lyapunov stability theory, the cooperative formation fault-tolerant performance analysis is presented. The proposed control strategy is validated through simulations.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":"19 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.70042","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144314996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Robust Output Feedback MPC of Antagonistic Pneumatic Artificial Muscle System","authors":"Huixing Yan,&nbsp;Hongqian Lu,&nbsp;Yefeng Yang,&nbsp;Yanming Fu","doi":"10.1049/cth2.70045","DOIUrl":"10.1049/cth2.70045","url":null,"abstract":"<p>Suspended constant force (SCF) control is a critical technology in suspended gravity offloading systems. However, inherent underactuation, unmodelled dynamics, and external disturbances can significantly degrade control performance and even compromise system stability. In this article, pneumatic artificial muscle (PAM) actuators are used as a replacement for traditional passive dampers to address the underactuation problem. Additionally, we propose a novel systematic robust output feedback model predictive control (ROFMPC) framework, which incorporates a radial basis function neural network (RBFNN)-based model compensator, a Luenberger state estimator, and a tube model predictive controller. The RBFNN-based model compensator compensates for unmodelled dynamics, while the Luenberger state estimator observes external disturbances. The model predictive controller then generates the optimal control sequence. Analytical results indicate that our designed SCF system encounters similar control challenges as those in antagonistic PAM (APAM). Therefore, sufficiently comprehensive numerical simulations and physical experiments are conducted on the APAM platform to verify the effectiveness of the proposed control framework. These results demonstrate that the proposed ROFMPC framework significantly improves force trajectory tracking performance for constant force control.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":"19 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.70045","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144314997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"System States and Disturbance Estimation Using Adaptive Integral Terminal Sliding Mode Observer for U-Tube Steam Generator Model in Nuclear Power Plant","authors":"Mokhtar Mohamed,&nbsp;Iestyn Pierce,&nbsp;Xinggang Yan,&nbsp;Hafiz Ahmed","doi":"10.1049/cth2.70050","DOIUrl":"10.1049/cth2.70050","url":null,"abstract":"<p>Designing water level control for a U-tube steam generator (UTSG) in nuclear power plants (NPP) remains a challenge, especially at low power demand due to unreliable steam flow measurements. This paper addresses the steam flow rate as a disturbance to the plant, treating it as an inaccessible variable. To estimate the disturbance (steam flow rate) and system states, an adaptive integral terminal sliding mode observer is developed. These estimated values can be utilized in the water level control design to enhance the reliability and performance of the control system. An adaptive observer is developed such that the augmented systems formed by the error dynamical systems and the designed adaptive laws are globally uniformly ultimately bounded. This technique is applied to a non-minimum phase system model representing the UTSG system to improve water level control and prevent possible serious consequences. Various disturbance signal forms with different amplitudes are simulated to demonstrate the reliability of the proposed technique. The simulation results show the effectiveness of the method proposed in this paper.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":"19 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.70050","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144314994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Autonomous Vehicle Path Tracking Using Event-Triggered MPC With Switching Model: Methodology and Real-World Validation","authors":"Zhaodong Zhou,&nbsp;Mingyuan Tao,&nbsp;Jiayi Qiu,&nbsp;Peng Zhang,&nbsp;Meng Xu,&nbsp;Jun Chen","doi":"10.1049/cth2.70046","DOIUrl":"10.1049/cth2.70046","url":null,"abstract":"<p>Model predictive control (MPC) is advantageous for autonomous vehicle path tracking but suffers from high computational complexity for real-time implementation. Event-triggered MPC aims to reduce this burden by optimizing the control inputs only when needed instead of every time step. Existing works in literature have been focused on algorithmic development and simulation validation for very specific scenarios. Therefore, event-triggered MPC in real-world full-size vehicle has not been thoroughly investigated. This work develops event-triggered MPC with switching model for autonomous vehicle lateral motion control, and implements it on a production vehicle for real-world validation. Experiments are conducted under both closed road and open road environments, with both low speed and high speed maneuvers, as well as stop-and-go scenarios. The efficacy of the proposed event-triggered MPC, in terms of computational load saving without sacrificing control performance, is clearly demonstrated. It is also demonstrated that event-triggered MPC can sometimes improve the control performance, even with less number of optimizations, thus contradicting to existing conclusions drawn from simulation.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":"19 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.70046","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144300166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Comprehensive Review of Solar Panel Performance Degradation and Adaptive Mitigation Strategies","authors":"Haoyu Yang,&nbsp;Yanyan Yin,&nbsp;Ahmed Abu-Siada","doi":"10.1049/cth2.70040","DOIUrl":"10.1049/cth2.70040","url":null,"abstract":"<p>This paper presents a comprehensive review of solar panel performance degradation in both industrial and residential sectors. Drawing on a wide range of academic studies, the paper systematically analyses the key factors affecting the performance of photovoltaic (PV) systems to provide in-depth understanding of degradation mechanisms along with effective countermeasures. These factors include the selection and properties of the materials used in PV panel manufacturing, changes in environmental conditions, the inherent degradation rate of materials and user behaviour. The paper aims to comprehensively reveal the mechanisms by which environmental and human factors contribute to PV panel performance degradation, assess their impact on the operational efficiency of the power systems and explore feasible adaptive solutions to mitigate or restore PV system performance. The paper also incorporates a technical framework aligned with the IEC 61850 standard and provides constructive recommendations for enhancing the efficiency and reliability of renewable power systems.</p><p>The paper holds substantial theoretical and practical significance. At a macro level, it contributes to reducing the overall cost of PV energy production while minimising investment in equipment maintenance and human resources. At a micro level, it enhances the utilisation efficiency and basic performance of PV systems. The recommendations of this paper not only support the sustainable growth of the renewable energy industry but also facilitate the synergistic expansion of the upstream and downstream industrial chain, fostering new employment opportunities and business potential. For individual users, businesses and the public sector, the paper provides a robust scientific foundation for developing future energy strategies with practical insights to advance global sustainable development goals.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":"19 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.70040","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144292893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extended State Observer-Based Motion Control of Robot Manipulators in Presence of Uncertainties and Disturbances","authors":"Muhammet Umut Danis,&nbsp;Zeki Yagiz Bayraktaroglu","doi":"10.1049/cth2.70043","DOIUrl":"10.1049/cth2.70043","url":null,"abstract":"<p>Robotic manipulators are complex mechanical systems that exhibit highly nonlinear dynamics and subject to various forms of disturbances such as friction, external forces and other unmodelled dynamics. Mathematical models representing robot dynamics are extensively used for design, simulation and control purposes, and can be derived through analytical and experimental methods. Dynamic behaviours predicted by mathematical models often deviate from the observed dynamics of robot manipulators because of external disturbances, parametric uncertainties, and unmodelled dynamics. The observer-based control that eliminates the need for highly accurate system modelling is an appealing approach for robot control. This paper introduces an extended state observer-based structure that can be either utilized as a stand-alone controller or implemented within a model-based adaptive control scheme. The proposed control scheme allows the implementation of extended state observers independently of the availability and quality of the dynamic model. The stability of the proposed controllers in presence of model uncertainties and generalized disturbances is investigated through the Lyapunov analysis. The experiments performed on a six-DoF industrial robot validate the theoretical stability results. Evaluation of performances of the proposed controllers in various operating conditions are presented in a comparative manner. Experimental results show that the extended state observer-based controller outperforms the adaptive controller in trajectory tracking performances.</p>","PeriodicalId":50382,"journal":{"name":"IET Control Theory and Applications","volume":"19 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/cth2.70043","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144292890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}