Pub Date : 2012-05-28DOI: 10.1109/CARPATHIANCC.2012.6228688
R. Magin
The premise of this work is that fractional (non-integer order) calculus can provide the basis for a greater understanding of the dynamic processes that occur in biological tissues. Such an understanding is fundamental in bioengineering where engineers seek a simpler description of the underlying multi-scale processes that occur, for example, when tissues are mechanically stressed or strained. Fractional order models work well in physics, electrochemistry and rheology, particularly in describing dielectric, magnetic and viscoelastic materials over extended ranges of time and frequency. In heat transfer and electrochemistry, for example, the half-order fractional integral is the natural integral operator connecting applied gradients (thermal or material) with the resultant diffusion of ions or heat. Can fractional calculus be applied in bioengineering to uncover similar relatively simple links between stress and strain in load-bearing tissues, such as cartilage, the electrical impedance of implanted cardiac pacemaker electrodes, or in predicting changes in the shear modulus of tumors developing in breast tissue? Since the constitutive properties of tissue depend on the micro-scale architecture of the cellular and extracellular networks, the challenge for the bioengineer is to develop new modeling, visualization and assessment tools that better predict the macro-scale mechanical performance from measurements observations at the micro- and nano-scale. In this paper I describe some of the characteristics of fractional calculus that I believe make it well suited for this application, and outline three areas of bioengineering research where fractional calculus is being applied.
{"title":"Fractional calculus in bioengineering: A tool to model complex dynamics","authors":"R. Magin","doi":"10.1109/CARPATHIANCC.2012.6228688","DOIUrl":"https://doi.org/10.1109/CARPATHIANCC.2012.6228688","url":null,"abstract":"The premise of this work is that fractional (non-integer order) calculus can provide the basis for a greater understanding of the dynamic processes that occur in biological tissues. Such an understanding is fundamental in bioengineering where engineers seek a simpler description of the underlying multi-scale processes that occur, for example, when tissues are mechanically stressed or strained. Fractional order models work well in physics, electrochemistry and rheology, particularly in describing dielectric, magnetic and viscoelastic materials over extended ranges of time and frequency. In heat transfer and electrochemistry, for example, the half-order fractional integral is the natural integral operator connecting applied gradients (thermal or material) with the resultant diffusion of ions or heat. Can fractional calculus be applied in bioengineering to uncover similar relatively simple links between stress and strain in load-bearing tissues, such as cartilage, the electrical impedance of implanted cardiac pacemaker electrodes, or in predicting changes in the shear modulus of tumors developing in breast tissue? Since the constitutive properties of tissue depend on the micro-scale architecture of the cellular and extracellular networks, the challenge for the bioengineer is to develop new modeling, visualization and assessment tools that better predict the macro-scale mechanical performance from measurements observations at the micro- and nano-scale. In this paper I describe some of the characteristics of fractional calculus that I believe make it well suited for this application, and outline three areas of bioengineering research where fractional calculus is being applied.","PeriodicalId":334936,"journal":{"name":"Proceedings of the 13th International Carpathian Control Conference (ICCC)","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123437738","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 : 2012-05-28DOI: 10.1109/CARPATHIANCC.2012.6228728
J. Snamina
The influence of non-uniform magnetic field on the beam with magnetorheological fluid is used to build the vibration control algorithms. A special laboratory stand with appropriate electromagnet was built to test free and forced vibrations of the beam with and without control. Experiments were done to determine the stiffness and damping parameters of the beam for various currents flowing in electromagnet coils. A vibration control algorithm was proposed, based on the system identification data and using the averaging technique of nonlinear system analysis.
{"title":"The application of a non-uniform magnetic field to semi-active vibration control of a beam with magnetorheological fluid","authors":"J. Snamina","doi":"10.1109/CARPATHIANCC.2012.6228728","DOIUrl":"https://doi.org/10.1109/CARPATHIANCC.2012.6228728","url":null,"abstract":"The influence of non-uniform magnetic field on the beam with magnetorheological fluid is used to build the vibration control algorithms. A special laboratory stand with appropriate electromagnet was built to test free and forced vibrations of the beam with and without control. Experiments were done to determine the stiffness and damping parameters of the beam for various currents flowing in electromagnet coils. A vibration control algorithm was proposed, based on the system identification data and using the averaging technique of nonlinear system analysis.","PeriodicalId":334936,"journal":{"name":"Proceedings of the 13th International Carpathian Control Conference (ICCC)","volume":"159 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123021892","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 : 2012-05-28DOI: 10.1109/CARPATHIANCC.2012.6228664
K. Kostúr
In many cases, direct measurement of temperatures in heating furnaces is impossible from various real reasons. Indirect measurement is one way for obtaining this important variable for a feedback control system. Generally, the classification of system for indirect measurement and the comparing of an uncertainty for direct and indirect measurement will be given in the paper. Principles of indirect measurement based on mathematical models will be describing including boundary conditions for their solution. Very important is the measuring precision and therefore will be given one way based on adaption of simulation model including its verification.
{"title":"Principles of indirect measurement temperature","authors":"K. Kostúr","doi":"10.1109/CARPATHIANCC.2012.6228664","DOIUrl":"https://doi.org/10.1109/CARPATHIANCC.2012.6228664","url":null,"abstract":"In many cases, direct measurement of temperatures in heating furnaces is impossible from various real reasons. Indirect measurement is one way for obtaining this important variable for a feedback control system. Generally, the classification of system for indirect measurement and the comparing of an uncertainty for direct and indirect measurement will be given in the paper. Principles of indirect measurement based on mathematical models will be describing including boundary conditions for their solution. Very important is the measuring precision and therefore will be given one way based on adaption of simulation model including its verification.","PeriodicalId":334936,"journal":{"name":"Proceedings of the 13th International Carpathian Control Conference (ICCC)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121760178","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 : 2012-05-28DOI: 10.1109/CARPATHIANCC.2012.6228650
J. Kačur, M. Durdán, M. Laciak
At technological processes in metallurgy and machine-industries plants is heating of the metals one of the most important operation have influence on production in term of efficiency, quality and costs. In term of quality steel coil annealing is necessary to known temperature inside the object. It is the place with a lowest temperature during annealing process. This paper deals about proposal of the “System for indirect measurement of the heat flows” in the annealing process. This system enable in real time provides information about behaviors of the inner temperatures in the coil during annealing process. Indirect measurement system of the heat flows is based on direct measurement of temperatures on protective cover, atmosphere temperature and coil's surface temperature in a furnace space of the annealing bell furnace. Proposed system was verified on laboratory measurements.
{"title":"System for indirect measurement of the heat flows in the annealing process","authors":"J. Kačur, M. Durdán, M. Laciak","doi":"10.1109/CARPATHIANCC.2012.6228650","DOIUrl":"https://doi.org/10.1109/CARPATHIANCC.2012.6228650","url":null,"abstract":"At technological processes in metallurgy and machine-industries plants is heating of the metals one of the most important operation have influence on production in term of efficiency, quality and costs. In term of quality steel coil annealing is necessary to known temperature inside the object. It is the place with a lowest temperature during annealing process. This paper deals about proposal of the “System for indirect measurement of the heat flows” in the annealing process. This system enable in real time provides information about behaviors of the inner temperatures in the coil during annealing process. Indirect measurement system of the heat flows is based on direct measurement of temperatures on protective cover, atmosphere temperature and coil's surface temperature in a furnace space of the annealing bell furnace. Proposed system was verified on laboratory measurements.","PeriodicalId":334936,"journal":{"name":"Proceedings of the 13th International Carpathian Control Conference (ICCC)","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121770874","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 : 2012-05-28DOI: 10.1109/CARPATHIANCC.2012.6228686
M. Macias, D. Sierociuk
In this paper the fractional order approach will be used for both modeling and control of the heat transfer model. As a controller the fractional order PID algorithm was used. We use two strategies for obtaining the parameters of fractional order PID controller. The first tune the orders with constant parameters obtained by traditional methods. The second when we arbitrary chose an order of the regulator and tune the parameters. Numerically obtained parameters were used to the control of the experimental setup of heat transfer. Results were presented and compared for each criterion and for both integer order and fractional PID control algorithms.
{"title":"Fractional order calculus for modeling and fractional PID control of the heating process","authors":"M. Macias, D. Sierociuk","doi":"10.1109/CARPATHIANCC.2012.6228686","DOIUrl":"https://doi.org/10.1109/CARPATHIANCC.2012.6228686","url":null,"abstract":"In this paper the fractional order approach will be used for both modeling and control of the heat transfer model. As a controller the fractional order PID algorithm was used. We use two strategies for obtaining the parameters of fractional order PID controller. The first tune the orders with constant parameters obtained by traditional methods. The second when we arbitrary chose an order of the regulator and tune the parameters. Numerically obtained parameters were used to the control of the experimental setup of heat transfer. Results were presented and compared for each criterion and for both integer order and fractional PID control algorithms.","PeriodicalId":334936,"journal":{"name":"Proceedings of the 13th International Carpathian Control Conference (ICCC)","volume":"311 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114958442","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 : 2012-05-28DOI: 10.1109/CARPATHIANCC.2012.6228736
M. Szega, H. Rusinowski, A. Milejski
Identification of empirical characteristic of power efficiency of multi-fuel fluidized-bed boiler CFB-Compact co-fired with hard coal, low-grade coal and biomass has been carried out. Measurement data from a distributed control system (DCS) of the boiler have been used. Thermal power of the boiler, molar fraction of oxygen in flue gases as well as part of the low-grade coal and part of the biomass chemical energy in the total chemical energy of the fuel have been assumed as independent variables in the empirical characteristics of the boiler power efficiency. The second-degree polynomial has been applied for an output mathematical form of the empirical characteristics of the boiler efficiency. For identification the estimators of the empirical characteristics coefficients the stepwise regression method has been used. The final conclusions has been formulated.
{"title":"Empirical energy characteristic of a fluidized-bed boiler based on measurements from a distributed control system","authors":"M. Szega, H. Rusinowski, A. Milejski","doi":"10.1109/CARPATHIANCC.2012.6228736","DOIUrl":"https://doi.org/10.1109/CARPATHIANCC.2012.6228736","url":null,"abstract":"Identification of empirical characteristic of power efficiency of multi-fuel fluidized-bed boiler CFB-Compact co-fired with hard coal, low-grade coal and biomass has been carried out. Measurement data from a distributed control system (DCS) of the boiler have been used. Thermal power of the boiler, molar fraction of oxygen in flue gases as well as part of the low-grade coal and part of the biomass chemical energy in the total chemical energy of the fuel have been assumed as independent variables in the empirical characteristics of the boiler power efficiency. The second-degree polynomial has been applied for an output mathematical form of the empirical characteristics of the boiler efficiency. For identification the estimators of the empirical characteristics coefficients the stepwise regression method has been used. The final conclusions has been formulated.","PeriodicalId":334936,"journal":{"name":"Proceedings of the 13th International Carpathian Control Conference (ICCC)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122567438","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 : 2012-05-28DOI: 10.1109/CARPATHIANCC.2012.6228753
M. Zecová, J. Terpák, L. Dorcák
This contribution deals with the creation of mathematical model of biomass gasification and combustion. In the introduction of contribution an analysis is given of biomass in terms of its occurrence, composition, and caloric value and also in terms of processes taking place with the biomass gasification and combustion. The idea for a complex model for the gasification and combustion of biomass is derived from the initial process analysis, which was suggested as a synthesis of elementary process models. In the case of elementary models the heating model, drying model, thermal decomposition model, oxidation of the solid component model, and oxidation of the volatile component model are considered. The heating model is based on the processes of heat accumulation and the transfer of heat by convection. The basis of the evaporation model is a process of the transformation of liquid water into water vapour. The remaining three models include the thermal decomposition of biomass, release of the volatile components and the burning of the solid components from it. Elementary process models were independently implemented and verified in a MATLAB environment as individual m-functions. The results from the simulations are also stated in this contribution, which are analyzed, and further use and method of model gasification and combustion is suggested.
{"title":"Mathematical model of gasification and combustion of biomass","authors":"M. Zecová, J. Terpák, L. Dorcák","doi":"10.1109/CARPATHIANCC.2012.6228753","DOIUrl":"https://doi.org/10.1109/CARPATHIANCC.2012.6228753","url":null,"abstract":"This contribution deals with the creation of mathematical model of biomass gasification and combustion. In the introduction of contribution an analysis is given of biomass in terms of its occurrence, composition, and caloric value and also in terms of processes taking place with the biomass gasification and combustion. The idea for a complex model for the gasification and combustion of biomass is derived from the initial process analysis, which was suggested as a synthesis of elementary process models. In the case of elementary models the heating model, drying model, thermal decomposition model, oxidation of the solid component model, and oxidation of the volatile component model are considered. The heating model is based on the processes of heat accumulation and the transfer of heat by convection. The basis of the evaporation model is a process of the transformation of liquid water into water vapour. The remaining three models include the thermal decomposition of biomass, release of the volatile components and the burning of the solid components from it. Elementary process models were independently implemented and verified in a MATLAB environment as individual m-functions. The results from the simulations are also stated in this contribution, which are analyzed, and further use and method of model gasification and combustion is suggested.","PeriodicalId":334936,"journal":{"name":"Proceedings of the 13th International Carpathian Control Conference (ICCC)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121482925","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 : 2012-05-28DOI: 10.1109/CARPATHIANCC.2012.6228623
D. Danciu, V. Răsvan, D. Popescu
In the paper there are considered two main aspects of the analysis for the dynamical properties of the recurrent neural networks with time-delays: the absolute stability and the global qualitative behavior of the system. The first aspect refers to the global asymptotic stability of the zero equilibrium and this means that only a single steady state of the neural network matters (the case of optimizers). The second aspect concerns global behavior of the systems with several equilibria. We have discussed the difficulties and the open problem concerning that second aspect.
{"title":"On the absolute stability for recurrent neural networks with time delays","authors":"D. Danciu, V. Răsvan, D. Popescu","doi":"10.1109/CARPATHIANCC.2012.6228623","DOIUrl":"https://doi.org/10.1109/CARPATHIANCC.2012.6228623","url":null,"abstract":"In the paper there are considered two main aspects of the analysis for the dynamical properties of the recurrent neural networks with time-delays: the absolute stability and the global qualitative behavior of the system. The first aspect refers to the global asymptotic stability of the zero equilibrium and this means that only a single steady state of the neural network matters (the case of optimizers). The second aspect concerns global behavior of the systems with several equilibria. We have discussed the difficulties and the open problem concerning that second aspect.","PeriodicalId":334936,"journal":{"name":"Proceedings of the 13th International Carpathian Control Conference (ICCC)","volume":"149 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133600766","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 : 2012-05-28DOI: 10.1109/CARPATHIANCC.2012.6228674
S. Kozák
The paper deals with new directions in research, development and applications of advanced control methods and structures based on the principles of optimality, robustness and intelligence. Present trends in the complex process control design demand an increasing degree of integration of numerical mathematics, control engineering methods, new control structures based of distribution, embedded network control structure and new information and communication technologies. Furthermore, increasing problems with interactions, process non-linearity's, operating constraints, time delays, uncertainties, and significant dead-times consequently lead to the necessity to develop more sophisticated control strategies. Advanced control methods and new distributed embedded control structures represent the most effective tools for realizing high performance of many technological processes. Main ideas covered in this paper are motivated namely by the development of new advanced control engineering methods (predictive, hybrid predictive, optimal, adaptive, robust, fuzzy logic, neural network) and new possibilities of their SW and HW realizations and successful implementation in industry.
{"title":"Advanced control engineering methods in modern technological applications","authors":"S. Kozák","doi":"10.1109/CARPATHIANCC.2012.6228674","DOIUrl":"https://doi.org/10.1109/CARPATHIANCC.2012.6228674","url":null,"abstract":"The paper deals with new directions in research, development and applications of advanced control methods and structures based on the principles of optimality, robustness and intelligence. Present trends in the complex process control design demand an increasing degree of integration of numerical mathematics, control engineering methods, new control structures based of distribution, embedded network control structure and new information and communication technologies. Furthermore, increasing problems with interactions, process non-linearity's, operating constraints, time delays, uncertainties, and significant dead-times consequently lead to the necessity to develop more sophisticated control strategies. Advanced control methods and new distributed embedded control structures represent the most effective tools for realizing high performance of many technological processes. Main ideas covered in this paper are motivated namely by the development of new advanced control engineering methods (predictive, hybrid predictive, optimal, adaptive, robust, fuzzy logic, neural network) and new possibilities of their SW and HW realizations and successful implementation in industry.","PeriodicalId":334936,"journal":{"name":"Proceedings of the 13th International Carpathian Control Conference (ICCC)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128437952","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 : 2012-05-28DOI: 10.1109/CARPATHIANCC.2012.6228669
I. Koštial, D. Dorčák, V. Šindler, J. Spisak, J. Glocek, J. Lišuch
For process control two basic approaches are used: outside - in approach and inside - out approach. Outside-in approach is user oriented. Process is forced to satisfy user objectives. Inside-out approach is process oriented. At this process driven approach process has dominant position and conditions have been created to realize it by the most natural way. Process oriented approach is based on knowing process fundamentals, where all control activities tend to satisfy the process optimally. This approach can bring important changes to the process. Presently in most of the solutions some regard is given to the process, but real process oriented approach is more exception than the rule. In this paper individual solution presents conceptual advantages of this approach and classical conceptions. External manipulation is by domination of the object by the subject. Object is passive and is waiting on the intervention. In the process approach the object is active and requires minimum external forces. Process is executed by transformation, mutation and alteration. Process manipulation can be physical or logical (process activation, deactivation).
{"title":"Process approach to the process control","authors":"I. Koštial, D. Dorčák, V. Šindler, J. Spisak, J. Glocek, J. Lišuch","doi":"10.1109/CARPATHIANCC.2012.6228669","DOIUrl":"https://doi.org/10.1109/CARPATHIANCC.2012.6228669","url":null,"abstract":"For process control two basic approaches are used: outside - in approach and inside - out approach. Outside-in approach is user oriented. Process is forced to satisfy user objectives. Inside-out approach is process oriented. At this process driven approach process has dominant position and conditions have been created to realize it by the most natural way. Process oriented approach is based on knowing process fundamentals, where all control activities tend to satisfy the process optimally. This approach can bring important changes to the process. Presently in most of the solutions some regard is given to the process, but real process oriented approach is more exception than the rule. In this paper individual solution presents conceptual advantages of this approach and classical conceptions. External manipulation is by domination of the object by the subject. Object is passive and is waiting on the intervention. In the process approach the object is active and requires minimum external forces. Process is executed by transformation, mutation and alteration. Process manipulation can be physical or logical (process activation, deactivation).","PeriodicalId":334936,"journal":{"name":"Proceedings of the 13th International Carpathian Control Conference (ICCC)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133439272","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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