Pub Date : 1999-07-12DOI: 10.1109/ISIE.1999.796761
E. Deticek
Improved characteristics of fluid power actuators due to integration of electronics and fluid power technologies have already become standard. Valves can be electronically actuated and can control hydraulic power quickly and accurately. There are sensors capable of transforming fluid power and mechanical variables into electronic signals. Appropriate control strategies and sophisticated control algorithms are required to overcome the disadvantages and nonlinear dynamic behavior of hydraulic drives. This is successfully obtainable only by implementation of digital control systems designed on the basis of modern control theory. Several types of conventional PID-controllers, adaptive controllers and fuzzy logic controllers have been developed. The purpose of the research work described in this paper was to explore the possibilities of inserting self-learning and self-organising characteristics into control algorithms for control of electrohydraulic drives. The proposed reinforcement learning method enables a faster adaption on parameter changes than some traditional learning methods. The results of experimental investigations are also shown.
{"title":"An intelligent position control of electrohydraulic drive using hybrid fuzzy control structure","authors":"E. Deticek","doi":"10.1109/ISIE.1999.796761","DOIUrl":"https://doi.org/10.1109/ISIE.1999.796761","url":null,"abstract":"Improved characteristics of fluid power actuators due to integration of electronics and fluid power technologies have already become standard. Valves can be electronically actuated and can control hydraulic power quickly and accurately. There are sensors capable of transforming fluid power and mechanical variables into electronic signals. Appropriate control strategies and sophisticated control algorithms are required to overcome the disadvantages and nonlinear dynamic behavior of hydraulic drives. This is successfully obtainable only by implementation of digital control systems designed on the basis of modern control theory. Several types of conventional PID-controllers, adaptive controllers and fuzzy logic controllers have been developed. The purpose of the research work described in this paper was to explore the possibilities of inserting self-learning and self-organising characteristics into control algorithms for control of electrohydraulic drives. The proposed reinforcement learning method enables a faster adaption on parameter changes than some traditional learning methods. The results of experimental investigations are also shown.","PeriodicalId":227402,"journal":{"name":"ISIE '99. Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.99TH8465)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122331328","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 : 1999-07-12DOI: 10.1109/ISIE.1999.801794
R. Leyva, L. Martínez-Salamero, J. Maixe, R. Giral, F. Guinjoan
The problem of stabilizing a boost regulator in large-signal situations using linear control laws is investigated in this paper. The control law is derived by means of a circuit-oriented procedure. After establishing a large-signal circuit model for the boost regulator including state-feedback, conditions for passivity in the resulting two-port are studied. As a consequence, a control law is directly derived from two-port passivity conditions, this ensuring regulator global stability even if the control saturation is taken into account. Subsequently, a linear analysis is performed in order to design the desired dynamics and robust behavior of the switching regulator. The linear analysis shows that only one feedback gain is necessary, provided that the coordinates of the equilibrium point are known. The use of regulator root locus, gain margin and phase margin diagrams as a function of the feedback gain allows to choose the proper value of this gain solving a certain trade-off for good dynamic response and robust behavior. ACSL simulations verify the analytical predictions.
{"title":"Large-signal stability of a boost regulator by means of linear control laws","authors":"R. Leyva, L. Martínez-Salamero, J. Maixe, R. Giral, F. Guinjoan","doi":"10.1109/ISIE.1999.801794","DOIUrl":"https://doi.org/10.1109/ISIE.1999.801794","url":null,"abstract":"The problem of stabilizing a boost regulator in large-signal situations using linear control laws is investigated in this paper. The control law is derived by means of a circuit-oriented procedure. After establishing a large-signal circuit model for the boost regulator including state-feedback, conditions for passivity in the resulting two-port are studied. As a consequence, a control law is directly derived from two-port passivity conditions, this ensuring regulator global stability even if the control saturation is taken into account. Subsequently, a linear analysis is performed in order to design the desired dynamics and robust behavior of the switching regulator. The linear analysis shows that only one feedback gain is necessary, provided that the coordinates of the equilibrium point are known. The use of regulator root locus, gain margin and phase margin diagrams as a function of the feedback gain allows to choose the proper value of this gain solving a certain trade-off for good dynamic response and robust behavior. ACSL simulations verify the analytical predictions.","PeriodicalId":227402,"journal":{"name":"ISIE '99. Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.99TH8465)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122958562","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 : 1999-07-12DOI: 10.1109/ISIE.1999.798688
D. Drevenšek, E. Urlep, M. Ćurković
This paper presents a laboratory prototype of the motor drive controller with a stress on user interface. For proper operation of the motor drive system certain parameters have to be set-up. Usually interaction between the human and motor drive controller is accomplished using an embedded keyboard and display. Usually there are several menus and every parameter is accessible with a corresponding code. Because PCs are available everywhere, the authors decided to implement the user interface on a PC running under the MS Windows operating system. The main benefit of such an interface is a simplified parameter setup. The PC and controller are connected with an RS232 cable. Parameter set-up can be downloaded to the controller, uploaded from the controller, saved into file and loaded from it. Besides parameter management, the user interface makes it possible to display selected variables and plot online time responses. There are also functions for parameter identification of the machine. Because the program in a motor drive controller is stored in the FLASH memory and hardware supports in-circuit programming, another function that supports firmware update was added. This way the software update is very simple and program customizing for specific requirements can be done easily.
{"title":"PC supported motor drive controller","authors":"D. Drevenšek, E. Urlep, M. Ćurković","doi":"10.1109/ISIE.1999.798688","DOIUrl":"https://doi.org/10.1109/ISIE.1999.798688","url":null,"abstract":"This paper presents a laboratory prototype of the motor drive controller with a stress on user interface. For proper operation of the motor drive system certain parameters have to be set-up. Usually interaction between the human and motor drive controller is accomplished using an embedded keyboard and display. Usually there are several menus and every parameter is accessible with a corresponding code. Because PCs are available everywhere, the authors decided to implement the user interface on a PC running under the MS Windows operating system. The main benefit of such an interface is a simplified parameter setup. The PC and controller are connected with an RS232 cable. Parameter set-up can be downloaded to the controller, uploaded from the controller, saved into file and loaded from it. Besides parameter management, the user interface makes it possible to display selected variables and plot online time responses. There are also functions for parameter identification of the machine. Because the program in a motor drive controller is stored in the FLASH memory and hardware supports in-circuit programming, another function that supports firmware update was added. This way the software update is very simple and program customizing for specific requirements can be done easily.","PeriodicalId":227402,"journal":{"name":"ISIE '99. Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.99TH8465)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123022593","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 : 1999-07-12DOI: 10.1109/ISIE.1999.801763
Leo Budin, L. Jelenkovic
This paper presents some experiments on Windows NT operating system trying to determine its timing limits. Experiments were concentrated on the context switching abilities in a multithreaded environment. For this purpose a program simulator is written and simulations performed. We detailed some characteristic times for different process priority classes and processor's speed. In this way we try to determine the usage of this operating system in a time-constrained (real-time) environment. For comparison, simulations were also performed on Windows 98 and Linux operating systems.
{"title":"Time-constrained programming in Windows NT environment","authors":"Leo Budin, L. Jelenkovic","doi":"10.1109/ISIE.1999.801763","DOIUrl":"https://doi.org/10.1109/ISIE.1999.801763","url":null,"abstract":"This paper presents some experiments on Windows NT operating system trying to determine its timing limits. Experiments were concentrated on the context switching abilities in a multithreaded environment. For this purpose a program simulator is written and simulations performed. We detailed some characteristic times for different process priority classes and processor's speed. In this way we try to determine the usage of this operating system in a time-constrained (real-time) environment. For comparison, simulations were also performed on Windows 98 and Linux operating systems.","PeriodicalId":227402,"journal":{"name":"ISIE '99. Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.99TH8465)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128462204","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 : 1999-07-12DOI: 10.1109/ISIE.1999.798735
M. Naumovic
A novel structure of cross-coupled observer-based controller for two manipulators which are cooperatively handling an object is proposed. The suggested cross coupling control is based on the idea of simulation of friction and stiffness of a virtual mechanical link which couples two electrical drives. The structure enables synchronous motion of the drives by velocity and angle positions of their shafts in the presence of constant reference signals and slow varying load torque disturbances. The design procedures of a common position controller, cross-coupling control and appropriate state observer are proposed. Results of analytical design are verified by simulation runs.
{"title":"Cross-coupled motion controller for two cooperating robot arms","authors":"M. Naumovic","doi":"10.1109/ISIE.1999.798735","DOIUrl":"https://doi.org/10.1109/ISIE.1999.798735","url":null,"abstract":"A novel structure of cross-coupled observer-based controller for two manipulators which are cooperatively handling an object is proposed. The suggested cross coupling control is based on the idea of simulation of friction and stiffness of a virtual mechanical link which couples two electrical drives. The structure enables synchronous motion of the drives by velocity and angle positions of their shafts in the presence of constant reference signals and slow varying load torque disturbances. The design procedures of a common position controller, cross-coupling control and appropriate state observer are proposed. Results of analytical design are verified by simulation runs.","PeriodicalId":227402,"journal":{"name":"ISIE '99. Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.99TH8465)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129139256","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 : 1999-07-12DOI: 10.1109/ISIE.1999.796881
D. Stajic, N. Peric, J. Deur
Friction appears in the bearings and reduction gear of controlled electrical drives and affects the quality of the position, speed or force control. The servosystem performance can be improved by implementation of acceleration feedback. For the reason that acceleration measurement is often either not possible or practical, the implementation of acceleration estimation by an observer or differentiation of speed is proposed. Another approach to friction influence compensation is based on the disturbance observer. Its advantage is that it can be applied generally to the estimation of various disturbances. This paper deals with these friction compensation methods which are not based on friction model, but on the compensation of friction as a disturbance. The efficiency of these methods in a servodrive with Stribeck friction is compared by computer simulation and experimentally on a servosystem laboratory model.
{"title":"Friction compensation methods in position and speed control systems","authors":"D. Stajic, N. Peric, J. Deur","doi":"10.1109/ISIE.1999.796881","DOIUrl":"https://doi.org/10.1109/ISIE.1999.796881","url":null,"abstract":"Friction appears in the bearings and reduction gear of controlled electrical drives and affects the quality of the position, speed or force control. The servosystem performance can be improved by implementation of acceleration feedback. For the reason that acceleration measurement is often either not possible or practical, the implementation of acceleration estimation by an observer or differentiation of speed is proposed. Another approach to friction influence compensation is based on the disturbance observer. Its advantage is that it can be applied generally to the estimation of various disturbances. This paper deals with these friction compensation methods which are not based on friction model, but on the compensation of friction as a disturbance. The efficiency of these methods in a servodrive with Stribeck friction is compared by computer simulation and experimentally on a servosystem laboratory model.","PeriodicalId":227402,"journal":{"name":"ISIE '99. Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.99TH8465)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129324033","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 : 1999-07-12DOI: 10.1109/ISIE.1999.801740
M. Efe, O. Kaynak
Neural networks and fuzzy inference systems are becoming well recognized tools of designing an identifier/controller capable of perceiving the operating environment and imitating human operator with high performance. The motivation behind the use of neuro-fuzzy approaches is based on the complexity of real life systems, ambiguities on sensory information or time varying nature of the system under investigation. In this respect, neuro-fuzzy design approaches combine architectural (by neural networks) and philosophical (by fuzzy systems) aspects of an expert resulting in an artificial brain, which can be used as an identifier or a controller. It is known that the fuzzy inference systems and neural networks are universal approximators. An architecture with an appropriate learning strategy can teach any mapping to such a system with a predefined realization error bound. The most questionable quality in the use of neuro-fuzzy architectures is the stable training. This tutorial considers various neuro-fuzzy structures and gradient based training procedures. Consideration is given to stabilization of training dynamics.
{"title":"Neuro-fuzzy approaches for identification and control of nonlinear systems","authors":"M. Efe, O. Kaynak","doi":"10.1109/ISIE.1999.801740","DOIUrl":"https://doi.org/10.1109/ISIE.1999.801740","url":null,"abstract":"Neural networks and fuzzy inference systems are becoming well recognized tools of designing an identifier/controller capable of perceiving the operating environment and imitating human operator with high performance. The motivation behind the use of neuro-fuzzy approaches is based on the complexity of real life systems, ambiguities on sensory information or time varying nature of the system under investigation. In this respect, neuro-fuzzy design approaches combine architectural (by neural networks) and philosophical (by fuzzy systems) aspects of an expert resulting in an artificial brain, which can be used as an identifier or a controller. It is known that the fuzzy inference systems and neural networks are universal approximators. An architecture with an appropriate learning strategy can teach any mapping to such a system with a predefined realization error bound. The most questionable quality in the use of neuro-fuzzy architectures is the stable training. This tutorial considers various neuro-fuzzy structures and gradient based training procedures. Consideration is given to stabilization of training dynamics.","PeriodicalId":227402,"journal":{"name":"ISIE '99. Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.99TH8465)","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124647592","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 : 1999-07-12DOI: 10.1109/ISIE.1999.798712
C. Moo, H. Yen, H. Cheng, C. Lee
A pragmatic and efficient method using consecutive orthogonal arrays is proposed for designing a fluorescent lamp electronic ballast with a self-excitation driving circuit. The circuit parameters of the electronic ballast to be determined are assigned as the control variables in the orthogonal arrays, and the average effects corresponding to each control variable are calculated from the circuit performances which are obtained from experimental tests. In accordance with the inferential rules, the average effects are used as the observational indexes to adjust the levels of the control variables for the subsequent orthogonal array. Through manipulating consecutive orthogonal arrays step by step, the applicable ranges of circuit parameters are shrunk, and then the region with desired output performances can be approached. The design procedure and the inferential rules are illustrated by an example of the electronic ballast with the self-excited series resonant inverter. In the design example, one can find 8 combinations of circuit parameters with the desired output performances from 5 steps of orthogonal array manipulation.
{"title":"The implementation of orthogonal array method on designing self-excited electronic ballast","authors":"C. Moo, H. Yen, H. Cheng, C. Lee","doi":"10.1109/ISIE.1999.798712","DOIUrl":"https://doi.org/10.1109/ISIE.1999.798712","url":null,"abstract":"A pragmatic and efficient method using consecutive orthogonal arrays is proposed for designing a fluorescent lamp electronic ballast with a self-excitation driving circuit. The circuit parameters of the electronic ballast to be determined are assigned as the control variables in the orthogonal arrays, and the average effects corresponding to each control variable are calculated from the circuit performances which are obtained from experimental tests. In accordance with the inferential rules, the average effects are used as the observational indexes to adjust the levels of the control variables for the subsequent orthogonal array. Through manipulating consecutive orthogonal arrays step by step, the applicable ranges of circuit parameters are shrunk, and then the region with desired output performances can be approached. The design procedure and the inferential rules are illustrated by an example of the electronic ballast with the self-excited series resonant inverter. In the design example, one can find 8 combinations of circuit parameters with the desired output performances from 5 steps of orthogonal array manipulation.","PeriodicalId":227402,"journal":{"name":"ISIE '99. Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.99TH8465)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130322796","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 : 1999-07-12DOI: 10.1109/ISIE.1999.801784
Sinisa Segvic
An autonomous robot with a single visual sensor is considered in a man-made environment with trihedral rectangular structure, in which one horizontal dimension is considerably larger than others (e.g. a long corridor). A property of such an environment is that both quantity and quality of navigationally useful information that can be acquired by a visual sensor depend strongly on the viewing direction. As shown by experiments, they are greatest when the viewing direction is parallel to the longitudinal corridor axis and quickly recede as it rotates toward latitudinal corridor axis. A method is proposed for determining the robot orientation in world coordinates based on principles of projective geometry and a priori knowledge about the environment. Results of preliminary experimentation under realistic conditions are shown and discussed.
{"title":"Using vanishing points for purposive adjustment of viewing direction","authors":"Sinisa Segvic","doi":"10.1109/ISIE.1999.801784","DOIUrl":"https://doi.org/10.1109/ISIE.1999.801784","url":null,"abstract":"An autonomous robot with a single visual sensor is considered in a man-made environment with trihedral rectangular structure, in which one horizontal dimension is considerably larger than others (e.g. a long corridor). A property of such an environment is that both quantity and quality of navigationally useful information that can be acquired by a visual sensor depend strongly on the viewing direction. As shown by experiments, they are greatest when the viewing direction is parallel to the longitudinal corridor axis and quickly recede as it rotates toward latitudinal corridor axis. A method is proposed for determining the robot orientation in world coordinates based on principles of projective geometry and a priori knowledge about the environment. Results of preliminary experimentation under realistic conditions are shown and discussed.","PeriodicalId":227402,"journal":{"name":"ISIE '99. Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.99TH8465)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126803179","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 : 1999-07-12DOI: 10.1109/ISIE.1999.801744
R. Luo, T. Chen, Chi-Yang Hu
A truly intelligent autonomous mobile robot should have a common representation model, which can simultaneously satisfy low level navigational capabilities, medium level self-referencing capabilities, high level motion planning capabilities, and the ability to be controlled through the Internet. In this presentation, the issues for a truly intelligent autonomous mobile robot is first addressed. The issues for supervisory control of an intelligent autonomous mobile robot through the Internet will also be discussed. Finally, the opportunities for the application of intelligent autonomous mobile robot is described. Video presentation to demonstrate the feasibility of these techniques is also included.
{"title":"Networked intelligent autonomous mobile robot: issues and opportunities","authors":"R. Luo, T. Chen, Chi-Yang Hu","doi":"10.1109/ISIE.1999.801744","DOIUrl":"https://doi.org/10.1109/ISIE.1999.801744","url":null,"abstract":"A truly intelligent autonomous mobile robot should have a common representation model, which can simultaneously satisfy low level navigational capabilities, medium level self-referencing capabilities, high level motion planning capabilities, and the ability to be controlled through the Internet. In this presentation, the issues for a truly intelligent autonomous mobile robot is first addressed. The issues for supervisory control of an intelligent autonomous mobile robot through the Internet will also be discussed. Finally, the opportunities for the application of intelligent autonomous mobile robot is described. Video presentation to demonstrate the feasibility of these techniques is also included.","PeriodicalId":227402,"journal":{"name":"ISIE '99. Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.99TH8465)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1999-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121063066","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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