Pub Date : 2000-12-04DOI: 10.1109/ISIE.2000.930522
A. Arias, J. L. Romeral, E. Aldabas, M. Jayne
A brief review of the different induction motor drives is done and its reason of being such a high matter of interest is summarised. Next, the direct torque control (DTC) in induction motors with its fundamental principles and schemes is described. Once the DTC is described, its main drawbacks are introduced. One of the goals of the paper is to overcome one of the worst disadvantages of the DTC, which is the existence of a considerable ripple in its torque response. The previously explained DTC limitations involve plenty of nonlinear functions. Therefore, artificial intelligence is suggested to overcome the DTC limitations. Hence, a fuzzy logic DTC controller, which is based on the classical DTC but includes a fuzzy logic controller, is described. Finally an optimised method of calculating the stator reference flux value is presented, which can be applied in any kind of induction motor drive. This optimised stator flux reference value not only improves the torque ripple, but also reduces the power consumption from the mains. Simulated results are shown to corroborate all the presented work and the updated workbench where all the experimentation is realised is also described.
{"title":"Fuzzy logic direct torque control","authors":"A. Arias, J. L. Romeral, E. Aldabas, M. Jayne","doi":"10.1109/ISIE.2000.930522","DOIUrl":"https://doi.org/10.1109/ISIE.2000.930522","url":null,"abstract":"A brief review of the different induction motor drives is done and its reason of being such a high matter of interest is summarised. Next, the direct torque control (DTC) in induction motors with its fundamental principles and schemes is described. Once the DTC is described, its main drawbacks are introduced. One of the goals of the paper is to overcome one of the worst disadvantages of the DTC, which is the existence of a considerable ripple in its torque response. The previously explained DTC limitations involve plenty of nonlinear functions. Therefore, artificial intelligence is suggested to overcome the DTC limitations. Hence, a fuzzy logic DTC controller, which is based on the classical DTC but includes a fuzzy logic controller, is described. Finally an optimised method of calculating the stator reference flux value is presented, which can be applied in any kind of induction motor drive. This optimised stator flux reference value not only improves the torque ripple, but also reduces the power consumption from the mains. Simulated results are shown to corroborate all the presented work and the updated workbench where all the experimentation is realised is also described.","PeriodicalId":298625,"journal":{"name":"ISIE'2000. Proceedings of the 2000 IEEE International Symposium on Industrial Electronics (Cat. No.00TH8543)","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127986263","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 : 2000-12-04DOI: 10.1109/ISIE.2000.930386
R. Garrido
A simple nonlinear PD controller is proposed to improve settling time in a DC servo. Experimental results shows that the proposed algorithm performs better than a linear PD. A simple tuning procedure is also proposed and a stability proof is given.
{"title":"Improving settling time in a servo using a simple nonlinear PD controller","authors":"R. Garrido","doi":"10.1109/ISIE.2000.930386","DOIUrl":"https://doi.org/10.1109/ISIE.2000.930386","url":null,"abstract":"A simple nonlinear PD controller is proposed to improve settling time in a DC servo. Experimental results shows that the proposed algorithm performs better than a linear PD. A simple tuning procedure is also proposed and a stability proof is given.","PeriodicalId":298625,"journal":{"name":"ISIE'2000. Proceedings of the 2000 IEEE International Symposium on Industrial Electronics (Cat. No.00TH8543)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115817450","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 : 2000-12-04DOI: 10.1109/ISIE.2000.930477
S. Cavalieri, S. Monforte
The aim of the paper is to evaluate the impact of the occurrence of faults on the IEC 61158 type 1 field-bus protocol. This communication system was developed for use in a process control environment, where robustness to the occurrence of a fault is an important requirement. After a survey of the protocol's main features, certain types of failures are defined, the occurrence of which may be critical for the communication system. It is shown that for some of the failures considered, the IEC 61158 type 1 protocol doesn't foresee any recovery procedure. When other failures occur, the fault states caused by them, may be not recovered by the fault recovery procedures provided for by the IEC 61158 type 1 standard. In particular it is shown that the standard provides for procedures aimed to recover faults caused by some kind of failure, but these procedures are unable to perform their goal. The evaluation of the effect of these faults on the performance of the communication system seems to be an important issue. For this reason, the paper presents a performance evaluation of the fault recovery mechanisms, foreseen by the IEC protocol, but unable to recover some faults. The evaluation is based on Petri Net model simulation, and is aimed at evaluating the impact on the recovery procedures on the information flow between control processes.
本文的目的是评估故障的发生对IEC 61158 1型现场总线协议的影响。该通信系统是为在过程控制环境中使用而开发的，其中对故障发生的鲁棒性是一个重要的要求。在对协议的主要特性进行调查之后，定义了某些类型的故障，这些故障的发生可能对通信系统至关重要。结果表明，对于所考虑的一些故障，IEC 61158 type 1协议没有预见到任何恢复过程。当发生其他故障时，由它们引起的故障状态可能无法通过IEC 61158类型1标准规定的故障恢复程序恢复。特别是，该标准规定了旨在恢复由某种故障引起的故障的程序，但这些程序无法实现其目标。评估这些故障对通信系统性能的影响似乎是一个重要的问题。为此，本文提出了一种故障恢复机制的性能评估，该机制是IEC协议所预见的，但无法恢复某些故障。该评估基于Petri网模型仿真，旨在评估恢复过程对控制过程之间信息流的影响。
{"title":"Petri net based fault tolerance evaluation of IEC 61158 field-bus standard","authors":"S. Cavalieri, S. Monforte","doi":"10.1109/ISIE.2000.930477","DOIUrl":"https://doi.org/10.1109/ISIE.2000.930477","url":null,"abstract":"The aim of the paper is to evaluate the impact of the occurrence of faults on the IEC 61158 type 1 field-bus protocol. This communication system was developed for use in a process control environment, where robustness to the occurrence of a fault is an important requirement. After a survey of the protocol's main features, certain types of failures are defined, the occurrence of which may be critical for the communication system. It is shown that for some of the failures considered, the IEC 61158 type 1 protocol doesn't foresee any recovery procedure. When other failures occur, the fault states caused by them, may be not recovered by the fault recovery procedures provided for by the IEC 61158 type 1 standard. In particular it is shown that the standard provides for procedures aimed to recover faults caused by some kind of failure, but these procedures are unable to perform their goal. The evaluation of the effect of these faults on the performance of the communication system seems to be an important issue. For this reason, the paper presents a performance evaluation of the fault recovery mechanisms, foreseen by the IEC protocol, but unable to recover some faults. The evaluation is based on Petri Net model simulation, and is aimed at evaluating the impact on the recovery procedures on the information flow between control processes.","PeriodicalId":298625,"journal":{"name":"ISIE'2000. Proceedings of the 2000 IEEE International Symposium on Industrial Electronics (Cat. No.00TH8543)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125182546","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 : 2000-12-04DOI: 10.1109/ISIE.2000.930511
R. Mateos, D. Libreros
Usually generator regulation of frequency and voltage is made with transducers for the frequency and voltage measurement. This work shows techniques of digital signals processing for measuring the frequency and voltage without harmonics affect, using algorithms with fuzzy logic voltage and frequency control, and PWM circuits. Besides the control has a peripheric of serial communication, which allows to change the operation point and gets stabilizer information of power in line. The program was proved on a laboratory machine with good results.
{"title":"The application of TMS320F240 for voltage/frequency fuzzy control of a synchronous generator","authors":"R. Mateos, D. Libreros","doi":"10.1109/ISIE.2000.930511","DOIUrl":"https://doi.org/10.1109/ISIE.2000.930511","url":null,"abstract":"Usually generator regulation of frequency and voltage is made with transducers for the frequency and voltage measurement. This work shows techniques of digital signals processing for measuring the frequency and voltage without harmonics affect, using algorithms with fuzzy logic voltage and frequency control, and PWM circuits. Besides the control has a peripheric of serial communication, which allows to change the operation point and gets stabilizer information of power in line. The program was proved on a laboratory machine with good results.","PeriodicalId":298625,"journal":{"name":"ISIE'2000. Proceedings of the 2000 IEEE International Symposium on Industrial Electronics (Cat. No.00TH8543)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125249608","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 : 2000-12-04DOI: 10.1109/ISIE.2000.930505
C. Hua, Chao-Ren Hsiao
Photovoltaic power systems are based on photovoltaic or solar modules which are very reliable and do not require any fuel or servicing. The object of this paper is to investigate power converter topologies and control techniques for a photovoltaic power supply system with parallel operation. All the modules have the same control configuration and each module includes inner current loop and outer voltage loop control in the proposed system. The system controller is based on a DSP and achieves the double loop control by using deadbeat control theory. Only two proportional controllers are required to implement the proposed control for the system with excellent output characteristics. The control is simple and effective with the easy program development. Instantaneous current sharing control is used to achieve the equal current distribution by a current sharing bus and ensure a fast dynamic response, equal load sharing capability and eliminates the circulation current. Simulation and experimental results verify the system performance.
{"title":"Implementation of distributed photovoltaic power supply systems","authors":"C. Hua, Chao-Ren Hsiao","doi":"10.1109/ISIE.2000.930505","DOIUrl":"https://doi.org/10.1109/ISIE.2000.930505","url":null,"abstract":"Photovoltaic power systems are based on photovoltaic or solar modules which are very reliable and do not require any fuel or servicing. The object of this paper is to investigate power converter topologies and control techniques for a photovoltaic power supply system with parallel operation. All the modules have the same control configuration and each module includes inner current loop and outer voltage loop control in the proposed system. The system controller is based on a DSP and achieves the double loop control by using deadbeat control theory. Only two proportional controllers are required to implement the proposed control for the system with excellent output characteristics. The control is simple and effective with the easy program development. Instantaneous current sharing control is used to achieve the equal current distribution by a current sharing bus and ensure a fast dynamic response, equal load sharing capability and eliminates the circulation current. Simulation and experimental results verify the system performance.","PeriodicalId":298625,"journal":{"name":"ISIE'2000. Proceedings of the 2000 IEEE International Symposium on Industrial Electronics (Cat. No.00TH8543)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131563141","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 : 2000-12-04DOI: 10.1109/ISIE.2000.930517
W. Suemitsu, G. A. Soares, R.S.S. Imbuzeiro
Several types of electronic converters, motors and semiconductor devices were the object of many research projects, producing an extensive bibliography; however, just a few of them were commercially established. The opening of the Brazilian market, stimulated by globalization, allows the national users access to a vast quantity of products, making some subjects almost impossible to be developed, and to generate commercial products, by the universities and research centers. The DC drives are still used in the industrial facilities, although the tendency is that they gradually disappear, as the cost of the AC drives decreases. Based in these facts, this paper considers the commercial perspectives of the research lines development of AC drives in Brazil.
{"title":"Electric motor drives in Brazil: a reflection on the perspectives of the development of commercial research lines","authors":"W. Suemitsu, G. A. Soares, R.S.S. Imbuzeiro","doi":"10.1109/ISIE.2000.930517","DOIUrl":"https://doi.org/10.1109/ISIE.2000.930517","url":null,"abstract":"Several types of electronic converters, motors and semiconductor devices were the object of many research projects, producing an extensive bibliography; however, just a few of them were commercially established. The opening of the Brazilian market, stimulated by globalization, allows the national users access to a vast quantity of products, making some subjects almost impossible to be developed, and to generate commercial products, by the universities and research centers. The DC drives are still used in the industrial facilities, although the tendency is that they gradually disappear, as the cost of the AC drives decreases. Based in these facts, this paper considers the commercial perspectives of the research lines development of AC drives in Brazil.","PeriodicalId":298625,"journal":{"name":"ISIE'2000. Proceedings of the 2000 IEEE International Symposium on Industrial Electronics (Cat. No.00TH8543)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128027799","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 : 2000-12-04DOI: 10.1109/ISIE.2000.930481
M. Gorzałczany, Adam Gluszek
The aim of this paper is to present and compare several neuro-fuzzy systems used as controllers for simulated backing up of a truck to a loading dock in a planar parking lot. The following systems have been considered: nfCon-the system proposed in this paper, an alternative neuro-fuzzy system reported in literature as well as the well-known ANFIS and NFIDENT systems. The main criterion of comparison of all systems is their performance (the accuracy of functioning) versus interpretability the transparency and the ability to explain generated actions; it also includes an analysis and pruning of the obtained fuzzy-rule bases.
{"title":"Computational intelligence in control-a comparison of several neuro-fuzzy systems","authors":"M. Gorzałczany, Adam Gluszek","doi":"10.1109/ISIE.2000.930481","DOIUrl":"https://doi.org/10.1109/ISIE.2000.930481","url":null,"abstract":"The aim of this paper is to present and compare several neuro-fuzzy systems used as controllers for simulated backing up of a truck to a loading dock in a planar parking lot. The following systems have been considered: nfCon-the system proposed in this paper, an alternative neuro-fuzzy system reported in literature as well as the well-known ANFIS and NFIDENT systems. The main criterion of comparison of all systems is their performance (the accuracy of functioning) versus interpretability the transparency and the ability to explain generated actions; it also includes an analysis and pruning of the obtained fuzzy-rule bases.","PeriodicalId":298625,"journal":{"name":"ISIE'2000. Proceedings of the 2000 IEEE International Symposium on Industrial Electronics (Cat. No.00TH8543)","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131771957","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 : 2000-12-04DOI: 10.1109/ISIE.2000.930479
A. Wegrzyn, M. Węgrzyn
The logic control program is usually specified by drawing the Petri net in terms of interface with the electro-mechanical devices and the environment of the system. In such case it is not immediately evident that the control system behaves in a satisfactory way. Industrial engineers prefer frequently a form of specification, like interpreted Petri Net, sequential function chart (SFC), Grafcet or Grafchart. On the other hand, some popular techniques are informal and do not provide means to validate the design. In the paper, modelling, analysis and synthesis of logic controller described by Petri nets is presented. Additional, the use of design/CPN system for modelling, testing and analysis of logic controllers described by means of coloured, interpreted Petri nets is shown. The proposed methods are especially useful in designing of industrial application specific logic controller (ASLC) with FPGA.
{"title":"Petri net-based specification, analysis and synthesis of logic controllers","authors":"A. Wegrzyn, M. Węgrzyn","doi":"10.1109/ISIE.2000.930479","DOIUrl":"https://doi.org/10.1109/ISIE.2000.930479","url":null,"abstract":"The logic control program is usually specified by drawing the Petri net in terms of interface with the electro-mechanical devices and the environment of the system. In such case it is not immediately evident that the control system behaves in a satisfactory way. Industrial engineers prefer frequently a form of specification, like interpreted Petri Net, sequential function chart (SFC), Grafcet or Grafchart. On the other hand, some popular techniques are informal and do not provide means to validate the design. In the paper, modelling, analysis and synthesis of logic controller described by Petri nets is presented. Additional, the use of design/CPN system for modelling, testing and analysis of logic controllers described by means of coloured, interpreted Petri nets is shown. The proposed methods are especially useful in designing of industrial application specific logic controller (ASLC) with FPGA.","PeriodicalId":298625,"journal":{"name":"ISIE'2000. Proceedings of the 2000 IEEE International Symposium on Industrial Electronics (Cat. No.00TH8543)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115339595","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 : 2000-12-04DOI: 10.1109/ISIE.2000.930483
Gi-Hyun Hwang, Dong-Wan Kim, Jae-Hyun Lee, Young-Joo An
This paper presents a design methodology of fuzzy system stabilizer (FPSS) using an adaptive evolution algorithm (AEA). The AEA consists of a genetic algorithm for a global search and evolution strategy for a local search in an adaptive manner when the present generation evolves into the next generation. The AEA is used to optimize the membership functions and scaling factors of FPSS. A single machine infinite system is applied to evaluate the usefulness of the FPSS. The results show that the proposed FPSS has a better control performance than the conventional power system stabilizer (CPSS) in the case of a three-phase fault under heavy load. To show the robustness of FPSS, it is applied to the system with disturbances such as change of mechanical torque and three-phase fault under the normal and light load. The results of the FPSS show a better robustness than that of the CPSS.
{"title":"Design of fuzzy power system stabilizer using adaptive evolutionary algorithm","authors":"Gi-Hyun Hwang, Dong-Wan Kim, Jae-Hyun Lee, Young-Joo An","doi":"10.1109/ISIE.2000.930483","DOIUrl":"https://doi.org/10.1109/ISIE.2000.930483","url":null,"abstract":"This paper presents a design methodology of fuzzy system stabilizer (FPSS) using an adaptive evolution algorithm (AEA). The AEA consists of a genetic algorithm for a global search and evolution strategy for a local search in an adaptive manner when the present generation evolves into the next generation. The AEA is used to optimize the membership functions and scaling factors of FPSS. A single machine infinite system is applied to evaluate the usefulness of the FPSS. The results show that the proposed FPSS has a better control performance than the conventional power system stabilizer (CPSS) in the case of a three-phase fault under heavy load. To show the robustness of FPSS, it is applied to the system with disturbances such as change of mechanical torque and three-phase fault under the normal and light load. The results of the FPSS show a better robustness than that of the CPSS.","PeriodicalId":298625,"journal":{"name":"ISIE'2000. Proceedings of the 2000 IEEE International Symposium on Industrial Electronics (Cat. No.00TH8543)","volume":"710 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115126686","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 : 2000-12-04DOI: 10.1109/ISIE.2000.930478
M. Adamski, J. Monteiro
The goal of this paper is to present the design methodology for the modelling and synthesis of discrete event controllers for compact, fast and reliable embedded systems, using related Petri net theory, rule-based system theory (conditional mathematical logic), and hardware description languages (VHDL, Verilog). The well structured specification, which is represented in the human readable logic language, has a direct impact on the validation, formal verification and implementation of application specific logic controllers (ASLC) mapped into reconfigurable logic devices (FPGA). Reprogrammable logic controllers (RLC) may replace traditional PLCs in many industrial applications.
{"title":"From interpreted Petri net specification to reprogrammable logic controller design","authors":"M. Adamski, J. Monteiro","doi":"10.1109/ISIE.2000.930478","DOIUrl":"https://doi.org/10.1109/ISIE.2000.930478","url":null,"abstract":"The goal of this paper is to present the design methodology for the modelling and synthesis of discrete event controllers for compact, fast and reliable embedded systems, using related Petri net theory, rule-based system theory (conditional mathematical logic), and hardware description languages (VHDL, Verilog). The well structured specification, which is represented in the human readable logic language, has a direct impact on the validation, formal verification and implementation of application specific logic controllers (ASLC) mapped into reconfigurable logic devices (FPGA). Reprogrammable logic controllers (RLC) may replace traditional PLCs in many industrial applications.","PeriodicalId":298625,"journal":{"name":"ISIE'2000. Proceedings of the 2000 IEEE International Symposium on Industrial Electronics (Cat. No.00TH8543)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123603976","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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