Pub Date : 2011-09-29DOI: 10.1109/MMAR.2011.6031354
J. Reuter, Matthias Jäkle, Felix Prauße, Felix Rey
Control-oriented magnetic models for solenoid actuators are analyzed and evaluated subject to their capabilities to reflect important features of the magnetic properties. Moreover, it is shown that undesired tuning requirements can be omitted by use of flux channel models. The focus here is put on the modeling of eddy currents since the accurate calculation of eddy current losses is a requirement for control strategies that are designed to minimize these losses. It is shown that flux channel models provide good results while the computational burden is low in comparison to finite element models. However, flux channel models require an additional step when used in flatness-based optimization schemes. This step is called state-decomposition and is explained in the second part of this paper.
{"title":"Model-based control of solenoid actuators using flux channel reluctance models","authors":"J. Reuter, Matthias Jäkle, Felix Prauße, Felix Rey","doi":"10.1109/MMAR.2011.6031354","DOIUrl":"https://doi.org/10.1109/MMAR.2011.6031354","url":null,"abstract":"Control-oriented magnetic models for solenoid actuators are analyzed and evaluated subject to their capabilities to reflect important features of the magnetic properties. Moreover, it is shown that undesired tuning requirements can be omitted by use of flux channel models. The focus here is put on the modeling of eddy currents since the accurate calculation of eddy current losses is a requirement for control strategies that are designed to minimize these losses. It is shown that flux channel models provide good results while the computational burden is low in comparison to finite element models. However, flux channel models require an additional step when used in flatness-based optimization schemes. This step is called state-decomposition and is explained in the second part of this paper.","PeriodicalId":440376,"journal":{"name":"2011 16th International Conference on Methods & Models in Automation & Robotics","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124440996","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 : 2011-09-29DOI: 10.1109/MMAR.2011.6031320
P. Plotnikov, J. Sokołowski
The non stationary, compressible Navier-Stokes equations are considered in a bounded hold-all domain. The nonhomegeneous boundary conditions are prescribed on the boundary of hold-all domain. The existence of the so-called weak normalized solutions for the model is established in [2]. In this talk we consider the associated shape optimization problems for the model. In the stationary case the drag of an obstacle is minimized. In the non stationary case the work for a fight scenario of an obstacle is minimized. It means that the boundary of an obstacle flying in a gas is optimized in such a way that for the given trajectory the energy required to attain a given point in the domain is minimized with respect to the shape of the obstacle. The family of admissible obstacles is sufficiently general and includes the standard shapes of an airfoil. We present the new results on the shape sensitivity analysis of the work functional for non stationary compressible Navier-Stokes equations [1]. In particular, the shape gradient is determined for the shape functional. The obtained results can be justified from mathematical point of view for the local solutions, or the global classical solutions of the model.
{"title":"Shape sensitivity analysis for the work functional","authors":"P. Plotnikov, J. Sokołowski","doi":"10.1109/MMAR.2011.6031320","DOIUrl":"https://doi.org/10.1109/MMAR.2011.6031320","url":null,"abstract":"The non stationary, compressible Navier-Stokes equations are considered in a bounded hold-all domain. The nonhomegeneous boundary conditions are prescribed on the boundary of hold-all domain. The existence of the so-called weak normalized solutions for the model is established in [2]. In this talk we consider the associated shape optimization problems for the model. In the stationary case the drag of an obstacle is minimized. In the non stationary case the work for a fight scenario of an obstacle is minimized. It means that the boundary of an obstacle flying in a gas is optimized in such a way that for the given trajectory the energy required to attain a given point in the domain is minimized with respect to the shape of the obstacle. The family of admissible obstacles is sufficiently general and includes the standard shapes of an airfoil. We present the new results on the shape sensitivity analysis of the work functional for non stationary compressible Navier-Stokes equations [1]. In particular, the shape gradient is determined for the shape functional. The obtained results can be justified from mathematical point of view for the local solutions, or the global classical solutions of the model.","PeriodicalId":440376,"journal":{"name":"2011 16th International Conference on Methods & Models in Automation & Robotics","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121709211","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 : 2011-09-29DOI: 10.1109/MMAR.2011.6031356
J. Będkowski, A. Maslowski
In the paper an algorithm of 3D data registration based on CUDA implementation is shown. The research is related to the problem of collecting 3D data with laser measurement system mounted on rotated head, to be used in mobile robot applications. Assumed performance of data registration algorithm is achieved, therefore it can used as On-line. The ICP (Iterative Closest Point) approach is chosen as registration method. Computation is based on massively parallel architecture of NVIDIA CUDA. The presented concept of 3D data matching is based on parallel computation used for fast nearest neighbor search. Nearest neighbor search procedure is using 3D space decomposition into cubic buckets, therefore the time of matching is deterministic.
{"title":"On-line data registration in OUTDOOR environment","authors":"J. Będkowski, A. Maslowski","doi":"10.1109/MMAR.2011.6031356","DOIUrl":"https://doi.org/10.1109/MMAR.2011.6031356","url":null,"abstract":"In the paper an algorithm of 3D data registration based on CUDA implementation is shown. The research is related to the problem of collecting 3D data with laser measurement system mounted on rotated head, to be used in mobile robot applications. Assumed performance of data registration algorithm is achieved, therefore it can used as On-line. The ICP (Iterative Closest Point) approach is chosen as registration method. Computation is based on massively parallel architecture of NVIDIA CUDA. The presented concept of 3D data matching is based on parallel computation used for fast nearest neighbor search. Nearest neighbor search procedure is using 3D space decomposition into cubic buckets, therefore the time of matching is deterministic.","PeriodicalId":440376,"journal":{"name":"2011 16th International Conference on Methods & Models in Automation & Robotics","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122135130","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 : 2011-09-29DOI: 10.1109/MMAR.2011.6031335
M. Zerikat, S. Chekroun, A. Mechernene
The main aim of this paper is to implement and evaluate a high performance sensorless vector control of Induction Motor drive. The parallel resistance parameters and rotor speed estimation for MRAS-Sensorless with Direct Field Oriented Control is discussed in this paper. An MRAS is employed to obtain the resistance parameters and speed estimates. This technique is implemented using the Field Oriented Control technique as it provides better control of motor torque with high dynamic performance. The motor model is designed and membership functions are chosen according to the parameters of the motor model. The aim of the proposed sensorless control is to improve the performance and robustness of the induction motor drives under non linear loads variations is presented in this work. The availability of the proposed structure scheme is tested in simulation with Matlab-software. The results conclude that the efficiency and reliability of the proposed sensorless controller is excellent under a variety of operating conditions of the IM drive.
{"title":"A robust MRAS-sensorless scheme based rotor and stator resistances estimation of a direct vector controlled induction motor drive","authors":"M. Zerikat, S. Chekroun, A. Mechernene","doi":"10.1109/MMAR.2011.6031335","DOIUrl":"https://doi.org/10.1109/MMAR.2011.6031335","url":null,"abstract":"The main aim of this paper is to implement and evaluate a high performance sensorless vector control of Induction Motor drive. The parallel resistance parameters and rotor speed estimation for MRAS-Sensorless with Direct Field Oriented Control is discussed in this paper. An MRAS is employed to obtain the resistance parameters and speed estimates. This technique is implemented using the Field Oriented Control technique as it provides better control of motor torque with high dynamic performance. The motor model is designed and membership functions are chosen according to the parameters of the motor model. The aim of the proposed sensorless control is to improve the performance and robustness of the induction motor drives under non linear loads variations is presented in this work. The availability of the proposed structure scheme is tested in simulation with Matlab-software. The results conclude that the efficiency and reliability of the proposed sensorless controller is excellent under a variety of operating conditions of the IM drive.","PeriodicalId":440376,"journal":{"name":"2011 16th International Conference on Methods & Models in Automation & Robotics","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133769098","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 : 2011-09-29DOI: 10.1109/MMAR.2011.6031308
Radosław Rudek, Agnieszka Rudek, P. Skworcow
In this paper, we consider an optimal sequence of tasks for systems that improve their performances due to autonomous learning (learning-by-doing). In particular, we focus on a problem of determining sequence of performed tasks for the autonomous learning systems to minimize the total weighted completion times of tasks. Fundamental for the presented approach is that schedule (a sequence of tasks) allows to efficiently utilize learning abilities of the system to optimize its objective, but it does not affect the system itself. To solve the problem, we prove an eliminating property that is used to construct a branch and bound algorithm and present some fast heuristic and metaheuristic methods. An extensive analysis of the efficiency of the proposed algorithms is also provided.
{"title":"An optimal sequence of tasks for autonomous learning systems","authors":"Radosław Rudek, Agnieszka Rudek, P. Skworcow","doi":"10.1109/MMAR.2011.6031308","DOIUrl":"https://doi.org/10.1109/MMAR.2011.6031308","url":null,"abstract":"In this paper, we consider an optimal sequence of tasks for systems that improve their performances due to autonomous learning (learning-by-doing). In particular, we focus on a problem of determining sequence of performed tasks for the autonomous learning systems to minimize the total weighted completion times of tasks. Fundamental for the presented approach is that schedule (a sequence of tasks) allows to efficiently utilize learning abilities of the system to optimize its objective, but it does not affect the system itself. To solve the problem, we prove an eliminating property that is used to construct a branch and bound algorithm and present some fast heuristic and metaheuristic methods. An extensive analysis of the efficiency of the proposed algorithms is also provided.","PeriodicalId":440376,"journal":{"name":"2011 16th International Conference on Methods & Models in Automation & Robotics","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133795419","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 : 2011-09-29DOI: 10.1109/MMAR.2011.6031357
K. Varadarajan, M. Vincze
Multi-robot networks used in surveillance, industrial manufacturing, defense and distributed monitoring require maximal coverage and connectivity while adapting to changes in environmental and channel conditions. Traditional algorithms attempt at solving this issue using deployment schemes and power control. In the case of mobile robot networks, the additional degree of freedom rendered by the mobility of the robots can additionally be used. In this paper we introduce a novel robot topology control mechanism aiming at maximizing coverage, connectivity and reliability using an irregular hexagonal static/mobile multi-robot deployment scheme. Experimental data, along with simulation results demonstrate connectivity enhancement under signal loss.
{"title":"Mobility aware topology control framework for dynamic multi-robot networks","authors":"K. Varadarajan, M. Vincze","doi":"10.1109/MMAR.2011.6031357","DOIUrl":"https://doi.org/10.1109/MMAR.2011.6031357","url":null,"abstract":"Multi-robot networks used in surveillance, industrial manufacturing, defense and distributed monitoring require maximal coverage and connectivity while adapting to changes in environmental and channel conditions. Traditional algorithms attempt at solving this issue using deployment schemes and power control. In the case of mobile robot networks, the additional degree of freedom rendered by the mobility of the robots can additionally be used. In this paper we introduce a novel robot topology control mechanism aiming at maximizing coverage, connectivity and reliability using an irregular hexagonal static/mobile multi-robot deployment scheme. Experimental data, along with simulation results demonstrate connectivity enhancement under signal loss.","PeriodicalId":440376,"journal":{"name":"2011 16th International Conference on Methods & Models in Automation & Robotics","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129598632","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 : 2011-09-29DOI: 10.1109/MMAR.2011.6031316
I. Dulęba, J. Jagodziński
Generating and solving the Chen-Fliess-Sussmann (CFS) equation for a given representation of motion is a crucial step in deriving controls to steer nilpotent nonholonomic systems using the Lafferriere-Sussmann method. The equation can be quite complicated, and its derivation differs substantially from one representation to another. Therefore instead to derive CFS for a given hard-to-compute representation we propose to derive it for any easy-to-compute representation and then to transform it to the given representation. For this purpose the Campbell-Baker-Hausdorff-Dynkin formula is applied. This approach is illustrated on generating and solving CFS for forward, backward and canonical representations.
{"title":"Generating Chen-Fliess-Sussmann equation via Campbell-Baker-Hausdorff-Dynkin formula","authors":"I. Dulęba, J. Jagodziński","doi":"10.1109/MMAR.2011.6031316","DOIUrl":"https://doi.org/10.1109/MMAR.2011.6031316","url":null,"abstract":"Generating and solving the Chen-Fliess-Sussmann (CFS) equation for a given representation of motion is a crucial step in deriving controls to steer nilpotent nonholonomic systems using the Lafferriere-Sussmann method. The equation can be quite complicated, and its derivation differs substantially from one representation to another. Therefore instead to derive CFS for a given hard-to-compute representation we propose to derive it for any easy-to-compute representation and then to transform it to the given representation. For this purpose the Campbell-Baker-Hausdorff-Dynkin formula is applied. This approach is illustrated on generating and solving CFS for forward, backward and canonical representations.","PeriodicalId":440376,"journal":{"name":"2011 16th International Conference on Methods & Models in Automation & Robotics","volume":"40 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132499640","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 : 2011-09-29DOI: 10.1109/MMAR.2011.6031330
A. Siewnicka, Bartlomiej Fajdek, K. Janiszowski, Katarzyna Pucyk
The paper presents a new numerical package for modelling and simulation of human circulatory system with an extension of coronary circulation model. The main aim of addition of the coronary model was to allow simulation and verification of the influence of the left ventricle assistance on the coronary flow conditions and the possibility of simulation of the coronary vessels occlusion. The whole package was implemented as a part of PExSim (Process Explorer and Simulation) application. As a result we have the useful tool, which gives an opportunity to study functions of individual components of the human circulatory system as well as the system as whole. It allows for simulation of proper and pathology circulation conditions, such as left or right heart failure. Implemented model of the ventricle assist device (VAD) gives the opportunity for modelling the influence of the heart assistance on the coronary flows and the imminent myocardial infarction conditions. Applied methods and the modelling data sets are presented. Analysis and comparison of the received results are included.
本文在冠状动脉循环模型的基础上，提出了一种新的模拟人体循环系统的数值方法。增加冠状动脉模型的主要目的是为了模拟和验证左心室辅助对冠状动脉血流状况的影响，以及模拟冠状血管闭塞的可能性。整个包作为PExSim (Process Explorer and Simulation)应用程序的一部分实现。因此，我们有了一个有用的工具，它提供了一个机会来研究人体循环系统的各个组成部分以及整个系统的功能。它允许模拟正常和病理循环条件，如左或右心力衰竭。心室辅助装置(VAD)的实现模型为模拟心脏辅助对冠状动脉血流和迫在眉睫的心肌梗死状况的影响提供了机会。给出了应用方法和建模数据集。并对所得结果进行了分析和比较。
{"title":"Modelling and Simulation of coronary circulation system","authors":"A. Siewnicka, Bartlomiej Fajdek, K. Janiszowski, Katarzyna Pucyk","doi":"10.1109/MMAR.2011.6031330","DOIUrl":"https://doi.org/10.1109/MMAR.2011.6031330","url":null,"abstract":"The paper presents a new numerical package for modelling and simulation of human circulatory system with an extension of coronary circulation model. The main aim of addition of the coronary model was to allow simulation and verification of the influence of the left ventricle assistance on the coronary flow conditions and the possibility of simulation of the coronary vessels occlusion. The whole package was implemented as a part of PExSim (Process Explorer and Simulation) application. As a result we have the useful tool, which gives an opportunity to study functions of individual components of the human circulatory system as well as the system as whole. It allows for simulation of proper and pathology circulation conditions, such as left or right heart failure. Implemented model of the ventricle assist device (VAD) gives the opportunity for modelling the influence of the heart assistance on the coronary flows and the imminent myocardial infarction conditions. Applied methods and the modelling data sets are presented. Analysis and comparison of the received results are included.","PeriodicalId":440376,"journal":{"name":"2011 16th International Conference on Methods & Models in Automation & Robotics","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124945895","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 : 2011-09-29DOI: 10.1109/MMAR.2011.6031361
M. He, Xiaoyan Xu
A mathematical model that describes the rotation speed regulation process of a main engine system is established. Then an adaptive control system is designed for the control of main engine rotation speed. The adaptive control system makes self-organizing through modification of its weighted values which are determined through correlative search, as well as a coefficient of smoothness is adopted to smooth the process of the weighted value modification. The adaptive control system contains a fault treatment algorithm which is able to maintain stability of main engine operation when the rotation speed regulation system operates in abnormal conditions. The result of simulation experiment shows that the application of designed adaptive control system is able to make the main engine rotation speed regulation process more effective.
{"title":"Study on main engine speed regulation model with adaptive control","authors":"M. He, Xiaoyan Xu","doi":"10.1109/MMAR.2011.6031361","DOIUrl":"https://doi.org/10.1109/MMAR.2011.6031361","url":null,"abstract":"A mathematical model that describes the rotation speed regulation process of a main engine system is established. Then an adaptive control system is designed for the control of main engine rotation speed. The adaptive control system makes self-organizing through modification of its weighted values which are determined through correlative search, as well as a coefficient of smoothness is adopted to smooth the process of the weighted value modification. The adaptive control system contains a fault treatment algorithm which is able to maintain stability of main engine operation when the rotation speed regulation system operates in abnormal conditions. The result of simulation experiment shows that the application of designed adaptive control system is able to make the main engine rotation speed regulation process more effective.","PeriodicalId":440376,"journal":{"name":"2011 16th International Conference on Methods & Models in Automation & Robotics","volume":"41 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120902083","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 : 2011-09-29DOI: 10.1109/MMAR.2011.6031325
B. Lampe, E. Rosenwasser
The paper describes the application of the Hill method for stability investigations in frequency domain of retarded linear time-periodic (RLCP) systems. An alternative approach on basis of the periodized characteristic equation (PCE) is presented. In contrast to previous approaches to this problem, the PCE method avoids convergence problems and the need for solving transcendent equations. The key idea consists in relating the set of solutions with a Fredholm integral equation of the second kind. Then, applying the Fredholm theory allows to overcome the convergence problems. Moreover, a new set of formulae has been derived having improved computational properties. A comparison of the PCE and the Hill method shows the benefit of the new approach.
{"title":"Hill method for linear periodic systems with delay","authors":"B. Lampe, E. Rosenwasser","doi":"10.1109/MMAR.2011.6031325","DOIUrl":"https://doi.org/10.1109/MMAR.2011.6031325","url":null,"abstract":"The paper describes the application of the Hill method for stability investigations in frequency domain of retarded linear time-periodic (RLCP) systems. An alternative approach on basis of the periodized characteristic equation (PCE) is presented. In contrast to previous approaches to this problem, the PCE method avoids convergence problems and the need for solving transcendent equations. The key idea consists in relating the set of solutions with a Fredholm integral equation of the second kind. Then, applying the Fredholm theory allows to overcome the convergence problems. Moreover, a new set of formulae has been derived having improved computational properties. A comparison of the PCE and the Hill method shows the benefit of the new approach.","PeriodicalId":440376,"journal":{"name":"2011 16th International Conference on Methods & Models in Automation & Robotics","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123245136","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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