Pub Date : 2023-12-06DOI: 10.37394/23203.2023.18.47
A. Kirichuka, F. Sadyrbaev
The generalized Liénard type differential equation is studied together with the two-point linear boundary conditions of the Sturm-Liouville type. The existence and multiplicity of solutions are considered. The existence under suitable conditions is shown to follow from the lower and upper functions theory. For multiplicity, the polar coordinates approach is used. The multiplicity results are based on the comparison between behavior of solutions near the trivial one, and solutions near the special one, which is preassumed to be non-oscillatory. The existence of the latter is required. It is shown also, that these conditions are fulfilled for a relatively broad class of equations. Some examples are constructed, which are supplied by comments and illustrations.
{"title":"On Boundary Value Problems for Liénard Type Equation","authors":"A. Kirichuka, F. Sadyrbaev","doi":"10.37394/23203.2023.18.47","DOIUrl":"https://doi.org/10.37394/23203.2023.18.47","url":null,"abstract":"The generalized Liénard type differential equation is studied together with the two-point linear boundary conditions of the Sturm-Liouville type. The existence and multiplicity of solutions are considered. The existence under suitable conditions is shown to follow from the lower and upper functions theory. For multiplicity, the polar coordinates approach is used. The multiplicity results are based on the comparison between behavior of solutions near the trivial one, and solutions near the special one, which is preassumed to be non-oscillatory. The existence of the latter is required. It is shown also, that these conditions are fulfilled for a relatively broad class of equations. Some examples are constructed, which are supplied by comments and illustrations.","PeriodicalId":39422,"journal":{"name":"WSEAS Transactions on Systems and Control","volume":"51 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138595613","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 : 2023-12-06DOI: 10.37394/23203.2023.18.48
I. Irtyshcheva, M. Stehnei, I. Kramarenko, O. Liashenko, H. Mykhalchynets, Nataliia Mykhalchynets, Viktor Neimet
The purpose of the article is the process of modeling the effectiveness of the financial market of Ukraine in the conditions of overcoming threats to economic security. Forecasting possible behavioral reactions to the integrated performance of the financial market of Ukraine is necessary for connection with the academic environment, the variability of risks formed by the content of influencing factors, by setting the volumes of critical operations to respond to the effect of influencing factors. This is because the volumes of critical financial market operations, according to its combinatorial structure, are also aimed at obtaining a result. Therefore, we suggest predicting possible behavioral reactions to the integrated performance of the financial market of Ukraine. The forecast is focused on obtaining reaction values regarding critical financial market operations for the next resolution/achievement of good target values. The received forecast of changes creates an opportunity with sufficient accuracy to reveal the conditions for the formation of results, notably that characteristic of critical operations of the financial market, using studies of its internal reactivity, which is guided by the action of influencing factors. According to the results of the performance evaluation, it is evident that the expected integral performance of the financial market of Ukraine will demonstrate a much lower expected increase in benefits due to the likely narrowing of the market capacity and reduction of investment options. The results of such analysis and forecasting will make it possible to reasonably approach the development of sets of priority actions within the framework of strategic maps, the fixation of outlined priorities, and predictive analysis of changes in their effectiveness over time (which provides visualization of the movement towards absorption or complete absorption of destabilizing processes in the financial market).
{"title":"Simulation of the Performance of the Financial Market of Ukraine in the Conditions of Overcoming Threats to Economic Security","authors":"I. Irtyshcheva, M. Stehnei, I. Kramarenko, O. Liashenko, H. Mykhalchynets, Nataliia Mykhalchynets, Viktor Neimet","doi":"10.37394/23203.2023.18.48","DOIUrl":"https://doi.org/10.37394/23203.2023.18.48","url":null,"abstract":"The purpose of the article is the process of modeling the effectiveness of the financial market of Ukraine in the conditions of overcoming threats to economic security. Forecasting possible behavioral reactions to the integrated performance of the financial market of Ukraine is necessary for connection with the academic environment, the variability of risks formed by the content of influencing factors, by setting the volumes of critical operations to respond to the effect of influencing factors. This is because the volumes of critical financial market operations, according to its combinatorial structure, are also aimed at obtaining a result. Therefore, we suggest predicting possible behavioral reactions to the integrated performance of the financial market of Ukraine. The forecast is focused on obtaining reaction values regarding critical financial market operations for the next resolution/achievement of good target values. The received forecast of changes creates an opportunity with sufficient accuracy to reveal the conditions for the formation of results, notably that characteristic of critical operations of the financial market, using studies of its internal reactivity, which is guided by the action of influencing factors. According to the results of the performance evaluation, it is evident that the expected integral performance of the financial market of Ukraine will demonstrate a much lower expected increase in benefits due to the likely narrowing of the market capacity and reduction of investment options. The results of such analysis and forecasting will make it possible to reasonably approach the development of sets of priority actions within the framework of strategic maps, the fixation of outlined priorities, and predictive analysis of changes in their effectiveness over time (which provides visualization of the movement towards absorption or complete absorption of destabilizing processes in the financial market).","PeriodicalId":39422,"journal":{"name":"WSEAS Transactions on Systems and Control","volume":"67 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138595988","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 : 2023-12-05DOI: 10.37394/23203.2023.18.45
C. Ciufudean, C. Buzduga
One of the objectives of the European Union (EU) as well as of other state authorities is to create safe roads for vehicles all over the EU space. Considering the rapid development of road traffic and, regrettably, an increase in the number of accidents, the system presented in this paper has the role of informing road traffic participants about infrastructure and environmental conditions. Hardware support, software support as well and further development of the ASRS 01 system are presented.
{"title":"Automatic System for Roadway Safety – ASRS 01","authors":"C. Ciufudean, C. Buzduga","doi":"10.37394/23203.2023.18.45","DOIUrl":"https://doi.org/10.37394/23203.2023.18.45","url":null,"abstract":"One of the objectives of the European Union (EU) as well as of other state authorities is to create safe roads for vehicles all over the EU space. Considering the rapid development of road traffic and, regrettably, an increase in the number of accidents, the system presented in this paper has the role of informing road traffic participants about infrastructure and environmental conditions. Hardware support, software support as well and further development of the ASRS 01 system are presented.","PeriodicalId":39422,"journal":{"name":"WSEAS Transactions on Systems and Control","volume":"127 39","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138599166","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 : 2023-12-05DOI: 10.37394/23203.2023.18.46
H. Oubouaddi, Fatima Ezzahra El Mansouri, Ali Bouklata, Ramzi Larhouti, A. Ouannou, Adil Brouri
Presently, the problem of parameter estimation of motors used in electrical vehicles is discussed. To make the control more efficient, a model of the electrical motor is developed. Then, a parameter estimation method is established to determine the parameters of the used electrical motor. The proposed method is easy and can be easily implemented. Furthermore, a mathematical model of an electrical vehicle’s motor using linear and nonlinear blocks is obtained. The given model will allow us to perform several experiments without any extra fees.
{"title":"Parameter Estimation of Electrical Vehicle Motor","authors":"H. Oubouaddi, Fatima Ezzahra El Mansouri, Ali Bouklata, Ramzi Larhouti, A. Ouannou, Adil Brouri","doi":"10.37394/23203.2023.18.46","DOIUrl":"https://doi.org/10.37394/23203.2023.18.46","url":null,"abstract":"Presently, the problem of parameter estimation of motors used in electrical vehicles is discussed. To make the control more efficient, a model of the electrical motor is developed. Then, a parameter estimation method is established to determine the parameters of the used electrical motor. The proposed method is easy and can be easily implemented. Furthermore, a mathematical model of an electrical vehicle’s motor using linear and nonlinear blocks is obtained. The given model will allow us to perform several experiments without any extra fees.","PeriodicalId":39422,"journal":{"name":"WSEAS Transactions on Systems and Control","volume":"141 39","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138598872","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 : 2023-11-27DOI: 10.37394/23203.2023.18.44
E. Ali, S. M. A. Elazim
In this paper, a new metaheuristic method, the Cuckoo Search (CS) approach, based on the life of a bird family is proposed for the optimal design of a Static Var Compensator (SVC) in a multimachine environment. The SVC parameter tuning problem is converted to an optimization problem which is solved by the CS approach. The performance of the proposed CS-based SVC (CSSVC) has been compared with Particle Swarm Optimization (PSO) based SVC (PSOSVC) under various operating conditions. The superiority of the suggested technique in damping oscillations and enhancing voltage profile over a wide range of operating conditions and system configurations is confirmed through eigenvalue, performance indices, and time domain simulation results over the PSO.
{"title":"Cuckoo Search Approach for Optimal SVC Design in A Multimachine Power System","authors":"E. Ali, S. M. A. Elazim","doi":"10.37394/23203.2023.18.44","DOIUrl":"https://doi.org/10.37394/23203.2023.18.44","url":null,"abstract":"In this paper, a new metaheuristic method, the Cuckoo Search (CS) approach, based on the life of a bird family is proposed for the optimal design of a Static Var Compensator (SVC) in a multimachine environment. The SVC parameter tuning problem is converted to an optimization problem which is solved by the CS approach. The performance of the proposed CS-based SVC (CSSVC) has been compared with Particle Swarm Optimization (PSO) based SVC (PSOSVC) under various operating conditions. The superiority of the suggested technique in damping oscillations and enhancing voltage profile over a wide range of operating conditions and system configurations is confirmed through eigenvalue, performance indices, and time domain simulation results over the PSO.","PeriodicalId":39422,"journal":{"name":"WSEAS Transactions on Systems and Control","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139231169","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 : 2023-11-15DOI: 10.37394/23203.2023.18.41
Mohammed Tloul, M. Schwarz, J. Börcsök
This paper investigates the utilization of model-checking as a potent method for verifying system designs, emphasizing its early error detection capabilities, reducing failures, increasing safety, and saving costs. The study explores the application of the UPPAAL tool and model-checking techniques within control systems. A case study in the paper concentrates on formally verifying Proportional Integral Derivative (PID) controllers, emphasizing integral windup issues. A model is constructed in UPPAAL for a control system that includes the system dynamics and the actuator limitations. The model’s accuracy is validated against the MATLAB/Simulink® model. Formal requirements addressing integral windup are formulated, and a practical model-checking example using UPPAAL illustrates its utility in control system verification.
{"title":"Formal Verification of Dynamical Control Systems (Addressing Integral Windup Phenomena Using Model-Checking)","authors":"Mohammed Tloul, M. Schwarz, J. Börcsök","doi":"10.37394/23203.2023.18.41","DOIUrl":"https://doi.org/10.37394/23203.2023.18.41","url":null,"abstract":"This paper investigates the utilization of model-checking as a potent method for verifying system designs, emphasizing its early error detection capabilities, reducing failures, increasing safety, and saving costs. The study explores the application of the UPPAAL tool and model-checking techniques within control systems. A case study in the paper concentrates on formally verifying Proportional Integral Derivative (PID) controllers, emphasizing integral windup issues. A model is constructed in UPPAAL for a control system that includes the system dynamics and the actuator limitations. The model’s accuracy is validated against the MATLAB/Simulink® model. Formal requirements addressing integral windup are formulated, and a practical model-checking example using UPPAAL illustrates its utility in control system verification.","PeriodicalId":39422,"journal":{"name":"WSEAS Transactions on Systems and Control","volume":"14 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139275505","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 : 2023-11-15DOI: 10.37394/23203.2023.18.40
J. F. Rosenblueth
It is well-known that, for a mathematical programming problem involving equality and inequality constraints, the uniqueness of a Lagrange multiplier associated with a local solution implies, under certain smoothness assumptions, second order necessary optimality conditions. Those conditions hold on a set of critical directions defined by those points satisfying the constraints and for which the minimizing function and the standard Lagrangian coincide. No similar links between uniqueness of multipliers and second order conditions seem to have been established for optimal control problems. In this paper, we provide some results in this direction. In particular, we study and completely solve a natural conjecture which provides, under uniqueness assumptions, nonnegative second variations on a classical cone of admissible directions.
{"title":"Admissible Directions in Optimal Control Under Uniqueness Assumptions","authors":"J. F. Rosenblueth","doi":"10.37394/23203.2023.18.40","DOIUrl":"https://doi.org/10.37394/23203.2023.18.40","url":null,"abstract":"It is well-known that, for a mathematical programming problem involving equality and inequality constraints, the uniqueness of a Lagrange multiplier associated with a local solution implies, under certain smoothness assumptions, second order necessary optimality conditions. Those conditions hold on a set of critical directions defined by those points satisfying the constraints and for which the minimizing function and the standard Lagrangian coincide. No similar links between uniqueness of multipliers and second order conditions seem to have been established for optimal control problems. In this paper, we provide some results in this direction. In particular, we study and completely solve a natural conjecture which provides, under uniqueness assumptions, nonnegative second variations on a classical cone of admissible directions.","PeriodicalId":39422,"journal":{"name":"WSEAS Transactions on Systems and Control","volume":"32 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139274472","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 : 2023-11-15DOI: 10.37394/23203.2023.18.42
M. Saad, Muad Alshara, Khaled Mustafa
In industrial processes, the most important loop is the liquid-level control loop. The coupled tank system CT-100 becomes an essential apparatus for process control researchers. This paper introduces two controller techniques to control the water level in the second tank as a single input single output system. The PID controller is designed to control the linearized model, where the controller parameters are tuned using the Ziegler- Nichols tuning method. In addition, Fuzzy PID is designed based on adequate knowledge and experience. The proposed control approaches are simulated using MATLAB Simulink. Then, the obtained results using these controllers are compared in terms of time response specifications and the ITAE criterion. It is also, tested for step-change tracking signal and disturbance rejection. Finally, the simulation results showed that the Fuzzy PID controller has a robust performance.
{"title":"Fuzzy PID Controller Design for a Coupled Tank Liquid Level Control System","authors":"M. Saad, Muad Alshara, Khaled Mustafa","doi":"10.37394/23203.2023.18.42","DOIUrl":"https://doi.org/10.37394/23203.2023.18.42","url":null,"abstract":"In industrial processes, the most important loop is the liquid-level control loop. The coupled tank system CT-100 becomes an essential apparatus for process control researchers. This paper introduces two controller techniques to control the water level in the second tank as a single input single output system. The PID controller is designed to control the linearized model, where the controller parameters are tuned using the Ziegler- Nichols tuning method. In addition, Fuzzy PID is designed based on adequate knowledge and experience. The proposed control approaches are simulated using MATLAB Simulink. Then, the obtained results using these controllers are compared in terms of time response specifications and the ITAE criterion. It is also, tested for step-change tracking signal and disturbance rejection. Finally, the simulation results showed that the Fuzzy PID controller has a robust performance.","PeriodicalId":39422,"journal":{"name":"WSEAS Transactions on Systems and Control","volume":"13 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139271046","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 : 2023-11-15DOI: 10.37394/23203.2023.18.43
Natthapat Thongsak, Nuanpan Lawson
COVID-19 has killed many people and continues to be a major problem in all countries around the world. Estimating COVID-19 data in advance is helpful for the World Health Organization and governments in countries all over the globe to prepare the necessary resources. However, some of this information may be missing and needs to be dealt with before processing to estimation. The transformation method of an auxiliary variable can assist by increasing the performance of estimating the population mean. A combined transformed variable is suggested for estimating population mean when a study variable contains some missing values with uniform nonresponse, and it is applied in an application to data on COVID-19 incidence. The bias and mean square error of the suggested estimator are investigated and the performance is compared with existing estimators via a simulation study and an application to COVID-19 data. The results show that the suggested combined transformed estimators overtake existing estimators in terms of higher efficiency which yields the estimated value of total deaths of COVID-19 equal to 29497 cases.
{"title":"A Combined Transformed Variable for Population Mean Estimators When Missing Data Occur with an Application to COVID-19 Incidence","authors":"Natthapat Thongsak, Nuanpan Lawson","doi":"10.37394/23203.2023.18.43","DOIUrl":"https://doi.org/10.37394/23203.2023.18.43","url":null,"abstract":"COVID-19 has killed many people and continues to be a major problem in all countries around the world. Estimating COVID-19 data in advance is helpful for the World Health Organization and governments in countries all over the globe to prepare the necessary resources. However, some of this information may be missing and needs to be dealt with before processing to estimation. The transformation method of an auxiliary variable can assist by increasing the performance of estimating the population mean. A combined transformed variable is suggested for estimating population mean when a study variable contains some missing values with uniform nonresponse, and it is applied in an application to data on COVID-19 incidence. The bias and mean square error of the suggested estimator are investigated and the performance is compared with existing estimators via a simulation study and an application to COVID-19 data. The results show that the suggested combined transformed estimators overtake existing estimators in terms of higher efficiency which yields the estimated value of total deaths of COVID-19 equal to 29497 cases.","PeriodicalId":39422,"journal":{"name":"WSEAS Transactions on Systems and Control","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139271270","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 : 2023-11-15DOI: 10.37394/23203.2023.18.39
W. Peerajit
Control charts comprise an excellent statistical process control tool for monitoring industrial processes. Especially, the CUSUM control chart is very sensitive to small-to-moderate process parameter changes. The proposed approach utilizes the numerical integral equation (NIE) method to approximate the average run length (ARL) of changes in the mean of a seasonal time series model with underlying exponential white noise running on a CUSUM control chart. This was achieved by solving a system of linear equations and integration through partitioning and summation using the area under the curve of a function obtained by applying the Gauss-Legendre quadrature. A numerical study was conducted to compare the capabilities of the ARL derivations obtained using the NIE method and explicit formulas to detect changes in the mean of a long-memory model with exponential white noise running on a CUSUM control chart. The results reveal that the performances of both were comparable in terms of the accuracy percentage, which was greater than 95%, meaning that the ARL values were highly consistent. Thus, the NIE method can be used to validate ARL results for this situation.
{"title":"Approximating the ARL of Changes in the Mean of a Seasonal Time Series Model with Exponential White Noise Running on a CUSUM Control Chart","authors":"W. Peerajit","doi":"10.37394/23203.2023.18.39","DOIUrl":"https://doi.org/10.37394/23203.2023.18.39","url":null,"abstract":"Control charts comprise an excellent statistical process control tool for monitoring industrial processes. Especially, the CUSUM control chart is very sensitive to small-to-moderate process parameter changes. The proposed approach utilizes the numerical integral equation (NIE) method to approximate the average run length (ARL) of changes in the mean of a seasonal time series model with underlying exponential white noise running on a CUSUM control chart. This was achieved by solving a system of linear equations and integration through partitioning and summation using the area under the curve of a function obtained by applying the Gauss-Legendre quadrature. A numerical study was conducted to compare the capabilities of the ARL derivations obtained using the NIE method and explicit formulas to detect changes in the mean of a long-memory model with exponential white noise running on a CUSUM control chart. The results reveal that the performances of both were comparable in terms of the accuracy percentage, which was greater than 95%, meaning that the ARL values were highly consistent. Thus, the NIE method can be used to validate ARL results for this situation.","PeriodicalId":39422,"journal":{"name":"WSEAS Transactions on Systems and Control","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139273096","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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