Pub Date : 2021-06-29DOI: 10.23919/ecc54610.2021.9654984
S. Ifqir, C. Combastel, A. Zolghadri, G. Alcalay, P. Goupil, Samuel Merlet
The problem studied in this paper is that of multi-sensor data-fusion for aircraft navigation during approach and landing. Three different sensor groups, namely, Inertial Reference System (IRS), Global Positioning System (GPS) and Instrument Landing System (ILS) are used complementarily to estimate aircraft 3D position in the final approach stage. The methodology takes advantage of set-membership tools and paves the way toward a new and simple online tuning of merging filter. The effectiveness of the proposed scheme is evaluated in terms of validity and accuracy using real flight data provided by Airbus.
{"title":"Multi-Sensor Data Fusion For Civil Aircraft IRS/GPS/ILS Integrated Navigation System","authors":"S. Ifqir, C. Combastel, A. Zolghadri, G. Alcalay, P. Goupil, Samuel Merlet","doi":"10.23919/ecc54610.2021.9654984","DOIUrl":"https://doi.org/10.23919/ecc54610.2021.9654984","url":null,"abstract":"The problem studied in this paper is that of multi-sensor data-fusion for aircraft navigation during approach and landing. Three different sensor groups, namely, Inertial Reference System (IRS), Global Positioning System (GPS) and Instrument Landing System (ILS) are used complementarily to estimate aircraft 3D position in the final approach stage. The methodology takes advantage of set-membership tools and paves the way toward a new and simple online tuning of merging filter. The effectiveness of the proposed scheme is evaluated in terms of validity and accuracy using real flight data provided by Airbus.","PeriodicalId":105499,"journal":{"name":"2021 European Control Conference (ECC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130038643","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 : 2021-06-29DOI: 10.23919/ecc54610.2021.9654921
A. V. Paramonov, D. Gerasimov, V. Nikiforov
This paper concerns the problem of simultaneous adaptive compensation of external unmatched disturbance and output reference tracking for linear time-invariant (LTI) systems with state, input, and output delays. The external disturbance and the reference signal are considered as multi-harmonic signals with unknown frequencies, amplitudes, and initial phases. The disturbance is unmeasurable and affects both the input and the output of the plant. The solution to the problem is based on technique of direct adaptive control without identification of the disturbance and reference signal parameters (biases, frequencies, phases, and amplitudes). This solution contains observers of parameterized disturbance and reference signal, a special modification of augmented error model and a direct adjustable controller providing asymptotic convergence of the tracking error to zero.
{"title":"Adaptive Regulation Problem for Linear Systems with State, Input and Output Delays *","authors":"A. V. Paramonov, D. Gerasimov, V. Nikiforov","doi":"10.23919/ecc54610.2021.9654921","DOIUrl":"https://doi.org/10.23919/ecc54610.2021.9654921","url":null,"abstract":"This paper concerns the problem of simultaneous adaptive compensation of external unmatched disturbance and output reference tracking for linear time-invariant (LTI) systems with state, input, and output delays. The external disturbance and the reference signal are considered as multi-harmonic signals with unknown frequencies, amplitudes, and initial phases. The disturbance is unmeasurable and affects both the input and the output of the plant. The solution to the problem is based on technique of direct adaptive control without identification of the disturbance and reference signal parameters (biases, frequencies, phases, and amplitudes). This solution contains observers of parameterized disturbance and reference signal, a special modification of augmented error model and a direct adjustable controller providing asymptotic convergence of the tracking error to zero.","PeriodicalId":105499,"journal":{"name":"2021 European Control Conference (ECC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130684166","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 : 2021-06-29DOI: 10.23919/ECC54610.2021.9654911
A. Anand, Stefan Loew, C. Bottasso
An Economic Nonlinear Model Predictive Controller (ENMPC) is designed for a wind turbine and battery based hybrid energy system. An explicit consideration of cyclic damages within the controller is implemented via externalization of Rainflow based cycle counting (RFC) algorithm from the Model Predictive Controller (MPC). This is achieved using Parametric Online Rainflow counting (PORFC) approach. Additionally, impact of stress history is considered directly inside the optimization problem by employing a stress residue which also helps overcome the limitation of using shorter horizon for cyclic damage estimation. The designed MPC controller is implemented using the state-of-the-art ACADOS framework. The performance of the controller is assessed in closed loop with a hybrid plant model consisting of a NREL 5MW onshore wind turbine and a 1MWh/1MW Li-ion battery. Simulation output indicates that the formulated controller results in profit gain with respect to a realistic base-case controller. Moreover, the formulated controller is found to conveniently handle model complexities, non-linearities, and system constraints resulting in suitable dynamic performance. An economically optimal closed-loop operation of the grid-connected hybrid plant is achieved, where the controller, using PORFC algorithm, optimizes a realistic monetary objective while explicitly considering the requirements from the electricity grid.
{"title":"Economic control of hybrid energy systems composed of wind turbine and battery","authors":"A. Anand, Stefan Loew, C. Bottasso","doi":"10.23919/ECC54610.2021.9654911","DOIUrl":"https://doi.org/10.23919/ECC54610.2021.9654911","url":null,"abstract":"An Economic Nonlinear Model Predictive Controller (ENMPC) is designed for a wind turbine and battery based hybrid energy system. An explicit consideration of cyclic damages within the controller is implemented via externalization of Rainflow based cycle counting (RFC) algorithm from the Model Predictive Controller (MPC). This is achieved using Parametric Online Rainflow counting (PORFC) approach. Additionally, impact of stress history is considered directly inside the optimization problem by employing a stress residue which also helps overcome the limitation of using shorter horizon for cyclic damage estimation. The designed MPC controller is implemented using the state-of-the-art ACADOS framework. The performance of the controller is assessed in closed loop with a hybrid plant model consisting of a NREL 5MW onshore wind turbine and a 1MWh/1MW Li-ion battery. Simulation output indicates that the formulated controller results in profit gain with respect to a realistic base-case controller. Moreover, the formulated controller is found to conveniently handle model complexities, non-linearities, and system constraints resulting in suitable dynamic performance. An economically optimal closed-loop operation of the grid-connected hybrid plant is achieved, where the controller, using PORFC algorithm, optimizes a realistic monetary objective while explicitly considering the requirements from the electricity grid.","PeriodicalId":105499,"journal":{"name":"2021 European Control Conference (ECC)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130351075","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 : 2021-06-29DOI: 10.23919/ecc54610.2021.9655067
Liliana Maria Ghinea, I. Necoara, M. Barbu
In this paper we consider composite optimization problems having the objective function formed as a sum of two terms, one has Lipschitz continuous gradient and another is differentiable but non-separable. Under these settings we design two random coordinate descent methods, one takes into account the composite form of the objective function, while the other algorithm disregards the composite form of the objective function yielding a random coordinate gradient descent scheme with a novel stepsize rule. Our methods are able to tackle both convex and non-convex problems. For these algorithms we also show that they are descent methods in expectation. Preliminary numerical results confirm the efficiency of our two algorithms.
{"title":"Random coordinate descent methods for non-separable composite optimization","authors":"Liliana Maria Ghinea, I. Necoara, M. Barbu","doi":"10.23919/ecc54610.2021.9655067","DOIUrl":"https://doi.org/10.23919/ecc54610.2021.9655067","url":null,"abstract":"In this paper we consider composite optimization problems having the objective function formed as a sum of two terms, one has Lipschitz continuous gradient and another is differentiable but non-separable. Under these settings we design two random coordinate descent methods, one takes into account the composite form of the objective function, while the other algorithm disregards the composite form of the objective function yielding a random coordinate gradient descent scheme with a novel stepsize rule. Our methods are able to tackle both convex and non-convex problems. For these algorithms we also show that they are descent methods in expectation. Preliminary numerical results confirm the efficiency of our two algorithms.","PeriodicalId":105499,"journal":{"name":"2021 European Control Conference (ECC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129768096","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 : 2021-06-29DOI: 10.23919/ecc54610.2021.9655052
Lovis Phlippen, Manuel Vossel, M. Fuente, K. Radermacher
Lightweight serial robots are highly suitable for tasks with human interaction. The low mass contributes to inherent safety properties due to lower inertial forces and torques. However, the slender structure makes such robots more compliant, which leads to higher deflections under load. This work introduces a straightforward method to identify the elastic parameters of a lightweight robot. The virtual joint method was used for elastostatic modelling of the robot. For the parameter identification process a set of robot poses was defined by a combination of two different angular positions for each of the seven joints. At each pose the robot was deformed by using a constant load and the resulting deflection was measured using an optical 3D localizer. Based on this data the unknown parameters of the elastostatic model were calculated. Finally, the accuracy of the elastostatic model was evaluated by implementing a compliance error compensation algorithm. Experimental evaluation with a loaded robot in a set of application oriented poses show an average improvement of the static position accuracy of about 65 %. The largest uncompensated deflection was 9.4 mm at a load of 20 N which could be compensated to 0.9 mm.
{"title":"Development and evaluation of a straightforward method to identify the elastic structure of a lightweight robot","authors":"Lovis Phlippen, Manuel Vossel, M. Fuente, K. Radermacher","doi":"10.23919/ecc54610.2021.9655052","DOIUrl":"https://doi.org/10.23919/ecc54610.2021.9655052","url":null,"abstract":"Lightweight serial robots are highly suitable for tasks with human interaction. The low mass contributes to inherent safety properties due to lower inertial forces and torques. However, the slender structure makes such robots more compliant, which leads to higher deflections under load. This work introduces a straightforward method to identify the elastic parameters of a lightweight robot. The virtual joint method was used for elastostatic modelling of the robot. For the parameter identification process a set of robot poses was defined by a combination of two different angular positions for each of the seven joints. At each pose the robot was deformed by using a constant load and the resulting deflection was measured using an optical 3D localizer. Based on this data the unknown parameters of the elastostatic model were calculated. Finally, the accuracy of the elastostatic model was evaluated by implementing a compliance error compensation algorithm. Experimental evaluation with a loaded robot in a set of application oriented poses show an average improvement of the static position accuracy of about 65 %. The largest uncompensated deflection was 9.4 mm at a load of 20 N which could be compensated to 0.9 mm.","PeriodicalId":105499,"journal":{"name":"2021 European Control Conference (ECC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131138532","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 : 2021-06-29DOI: 10.23919/ecc54610.2021.9654996
Zonglin Liu, O. Stursberg
This paper introduces a scheme for distributed solution for mixed-integer quadratic programming (MIQP) problems, which stem from, e.g., optimal control problems of networked systems involving hybrid dynamics. The centralized solution of this class of problem is often very complicated due to the NP-hard nature of MIQP, especially when a larger number of subsystems is to be considered. The proposed distributed solution is carried out sequentially by employing different stages, each of which uses one optimality condition formulated for the MIQP problem. These conditions guide the decomposition and the solution process, so that the overall complexity is reduced significantly compared to the centralized solution. Efficiency with respect to computation times and performance is confirmed by a set of numerical examples.
{"title":"Distributed Solution of MIQP Problems Arising for Networked Systems with Coupling Constraints","authors":"Zonglin Liu, O. Stursberg","doi":"10.23919/ecc54610.2021.9654996","DOIUrl":"https://doi.org/10.23919/ecc54610.2021.9654996","url":null,"abstract":"This paper introduces a scheme for distributed solution for mixed-integer quadratic programming (MIQP) problems, which stem from, e.g., optimal control problems of networked systems involving hybrid dynamics. The centralized solution of this class of problem is often very complicated due to the NP-hard nature of MIQP, especially when a larger number of subsystems is to be considered. The proposed distributed solution is carried out sequentially by employing different stages, each of which uses one optimality condition formulated for the MIQP problem. These conditions guide the decomposition and the solution process, so that the overall complexity is reduced significantly compared to the centralized solution. Efficiency with respect to computation times and performance is confirmed by a set of numerical examples.","PeriodicalId":105499,"journal":{"name":"2021 European Control Conference (ECC)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124807630","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 : 2021-06-29DOI: 10.23919/ecc54610.2021.9654973
D. Balandin, R. Biryukov, M. Kogan
In this paper, we consider multi-objective mini-max problems with criteria being maxima of functionals. We determine a domain in the criteria space containing Pareto optimal points. The upper boundary of this domain corresponds to Pareto suboptimal solutions minimizing maxima of weighted sums of these functionals, while the lower one is computed using the same Pareto suboptimal solutions. This domain allows to evaluate a "proximity" of any solutions of the multi-objective problem to Pareto optimal solutions, which minimize weighted sums of the criteria. The proposed approach is applied to multi-objective control designs for continuous and discrete LTV systems and LTI systems over finite and infinite time horizons, respectively. The criteria used are H∞ norms with transients for several controlled outputs. Pareto suboptimal controls in such problems turn out to be H∞ controls with transients for combined outputs. State feedback gains of these controllers are computed in terms of solutions to differential or difference LMIs. Numerical example illustrates the theoretical results.
{"title":"Pareto suboptimal H∞ controls with transients","authors":"D. Balandin, R. Biryukov, M. Kogan","doi":"10.23919/ecc54610.2021.9654973","DOIUrl":"https://doi.org/10.23919/ecc54610.2021.9654973","url":null,"abstract":"In this paper, we consider multi-objective mini-max problems with criteria being maxima of functionals. We determine a domain in the criteria space containing Pareto optimal points. The upper boundary of this domain corresponds to Pareto suboptimal solutions minimizing maxima of weighted sums of these functionals, while the lower one is computed using the same Pareto suboptimal solutions. This domain allows to evaluate a \"proximity\" of any solutions of the multi-objective problem to Pareto optimal solutions, which minimize weighted sums of the criteria. The proposed approach is applied to multi-objective control designs for continuous and discrete LTV systems and LTI systems over finite and infinite time horizons, respectively. The criteria used are H∞ norms with transients for several controlled outputs. Pareto suboptimal controls in such problems turn out to be H∞ controls with transients for combined outputs. State feedback gains of these controllers are computed in terms of solutions to differential or difference LMIs. Numerical example illustrates the theoretical results.","PeriodicalId":105499,"journal":{"name":"2021 European Control Conference (ECC)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128411073","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 : 2021-06-29DOI: 10.23919/ecc54610.2021.9654979
M. Malekzadeh, I. Papamichail, M. Papageorgiou
Lane-free traffic has been recently proposed for connected automated vehicles (CAV). As incremental changes of the road width in lane-free traffic lead to corresponding incremental changes of the traffic flow capacity, the concept of internal boundary control can be used to optimize infrastructure utilization. Internal boundary control leads to flexible sharing of the total road width and capacity among the two traffic directions (of a highway or an arterial) in real-time, in response to the prevailing traffic conditions. A feedback-based Linear-Quadratic regulator with Integral action (LQI regulator) is appropriately developed in this paper to efficiently address this problem. Simulation investigations, involving a realistic highway stretch, demonstrate that the proposed simple LQI regulator is robust and very efficient.
{"title":"Internal Boundary Control of Lane-free Automated Vehicle Traffic using a Linear Quadratic Integral Regulator","authors":"M. Malekzadeh, I. Papamichail, M. Papageorgiou","doi":"10.23919/ecc54610.2021.9654979","DOIUrl":"https://doi.org/10.23919/ecc54610.2021.9654979","url":null,"abstract":"Lane-free traffic has been recently proposed for connected automated vehicles (CAV). As incremental changes of the road width in lane-free traffic lead to corresponding incremental changes of the traffic flow capacity, the concept of internal boundary control can be used to optimize infrastructure utilization. Internal boundary control leads to flexible sharing of the total road width and capacity among the two traffic directions (of a highway or an arterial) in real-time, in response to the prevailing traffic conditions. A feedback-based Linear-Quadratic regulator with Integral action (LQI regulator) is appropriately developed in this paper to efficiently address this problem. Simulation investigations, involving a realistic highway stretch, demonstrate that the proposed simple LQI regulator is robust and very efficient.","PeriodicalId":105499,"journal":{"name":"2021 European Control Conference (ECC)","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125917041","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 : 2021-06-29DOI: 10.23919/ECC54610.2021.9654958
Alexander Schwab, Florian Littek, J. Lunze
This paper presents a novel approach to the networked control of differentially driven robots using artificial potential fields. A set of multiple robots is considered, where each robot should travel to its individual destination while avoiding collisions with other robots. The transition to the individual destination is carried out cooperatively based on information that can be gathered with the communication network. The novelty of the presented solution lies in the deduction of the orientation control. It will be shown that the maximisation of the translatory velocity results in the robots to turn correctly to their destinations. The effectiveness of the proposed approach is demonstrated by experimental results.
{"title":"Experimental Evaluation of a Novel Approach to Cooperative Control of Multiple Robots with Artificial Potential Fields","authors":"Alexander Schwab, Florian Littek, J. Lunze","doi":"10.23919/ECC54610.2021.9654958","DOIUrl":"https://doi.org/10.23919/ECC54610.2021.9654958","url":null,"abstract":"This paper presents a novel approach to the networked control of differentially driven robots using artificial potential fields. A set of multiple robots is considered, where each robot should travel to its individual destination while avoiding collisions with other robots. The transition to the individual destination is carried out cooperatively based on information that can be gathered with the communication network. The novelty of the presented solution lies in the deduction of the orientation control. It will be shown that the maximisation of the translatory velocity results in the robots to turn correctly to their destinations. The effectiveness of the proposed approach is demonstrated by experimental results.","PeriodicalId":105499,"journal":{"name":"2021 European Control Conference (ECC)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127144934","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 : 2021-06-29DOI: 10.23919/ecc54610.2021.9654998
Roberto Tazzari, I. Azzollini, L. Marconi
The paper deals with autonomous Unmanned Ground Vehicles developed for precision agriculture contexts. The focus of the paper is on the design of an adaptive observer for slip estimation ensuring exponential convergence to the real slip coefficients. Uniform global exponential stability of the origin of the error system is shown via Lyapunov analysis and persistency of excitation arguments. Furthermore, robustness to additive perturbations is shown in terms of Input-to-State Stability. Experimental results validate the effectiveness of the proposed estimator even in presence of noisy measurements.
{"title":"An Adaptive Observer approach to Slip Estimation for Agricultural Tracked Vehicles","authors":"Roberto Tazzari, I. Azzollini, L. Marconi","doi":"10.23919/ecc54610.2021.9654998","DOIUrl":"https://doi.org/10.23919/ecc54610.2021.9654998","url":null,"abstract":"The paper deals with autonomous Unmanned Ground Vehicles developed for precision agriculture contexts. The focus of the paper is on the design of an adaptive observer for slip estimation ensuring exponential convergence to the real slip coefficients. Uniform global exponential stability of the origin of the error system is shown via Lyapunov analysis and persistency of excitation arguments. Furthermore, robustness to additive perturbations is shown in terms of Input-to-State Stability. Experimental results validate the effectiveness of the proposed estimator even in presence of noisy measurements.","PeriodicalId":105499,"journal":{"name":"2021 European Control Conference (ECC)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123516343","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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