Pub Date : 2013-04-23DOI: 10.1109/ICIT.2013.6505730
M. Ferdosian, H. Abdi, A. Bazaei
There is a continuously growing demand for wind power generation capacity. This situation forces the revision of the grid codes requirements, to remain connected during grid faults, i.e., to ride through the faults, and contribute to system stability during fault condition. In a typical fault condition, the voltage at the Point of Common Coupling (PCC) drops below 80% immediately and the rotor speed of induction generators becomes unstable. In this paper, Unified Power Flow Controller (UPFC) is used to improve the low voltage ride- through (LVRT) of wind energy conversion system (WECS) and to damp the rotor speed oscillations of induction generator under fault conditions. By controlling the UPFC as a virtual inductor, we aims to increase the voltage at the terminals of the wind energy conversion system (WECS) and thereby mitigate the destabilizing electrical torque and power during the fault. The WECS is considered as a fixed-speed system, equipped with a squirrel-cage induction generator. The simulation results show that UPFC can improve the LVRT and rotor stability of the WECS.
{"title":"Improved dynamic performance of wind energy conversion system by UPFC","authors":"M. Ferdosian, H. Abdi, A. Bazaei","doi":"10.1109/ICIT.2013.6505730","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505730","url":null,"abstract":"There is a continuously growing demand for wind power generation capacity. This situation forces the revision of the grid codes requirements, to remain connected during grid faults, i.e., to ride through the faults, and contribute to system stability during fault condition. In a typical fault condition, the voltage at the Point of Common Coupling (PCC) drops below 80% immediately and the rotor speed of induction generators becomes unstable. In this paper, Unified Power Flow Controller (UPFC) is used to improve the low voltage ride- through (LVRT) of wind energy conversion system (WECS) and to damp the rotor speed oscillations of induction generator under fault conditions. By controlling the UPFC as a virtual inductor, we aims to increase the voltage at the terminals of the wind energy conversion system (WECS) and thereby mitigate the destabilizing electrical torque and power during the fault. The WECS is considered as a fixed-speed system, equipped with a squirrel-cage induction generator. The simulation results show that UPFC can improve the LVRT and rotor stability of the WECS.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133095967","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505865
R. Bartz
This paper describes an approach to combine standards specified for the automotive test data management with the widely used Unified Modeling Language (UML). The major challenges in the automotive test data management domain include coping with a huge amount of data produced, considering their long lifetime, and trying to re-use as much as possible of the already acquired knowledge. For this purpose the automotive standards organization ASAM (Association for Standardization of Automation and Measuring Systems) has specified a storage standard called Open Data Services (ODS), which allows users to design data models fitted to their specific needs while keeping general classification information for generic use. On the other hand, object oriented concepts have evolved in the software technology domain, and UML has emerged as the most important standard to specify software-based systems. Given the similarities between the goals of ODS and aspects of UML that describe the static parts of a software system, this paper proposes a mapping between these two technologies.
{"title":"Mapping data models of the standardized automotive testing data storage to the unified modeling language","authors":"R. Bartz","doi":"10.1109/ICIT.2013.6505865","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505865","url":null,"abstract":"This paper describes an approach to combine standards specified for the automotive test data management with the widely used Unified Modeling Language (UML). The major challenges in the automotive test data management domain include coping with a huge amount of data produced, considering their long lifetime, and trying to re-use as much as possible of the already acquired knowledge. For this purpose the automotive standards organization ASAM (Association for Standardization of Automation and Measuring Systems) has specified a storage standard called Open Data Services (ODS), which allows users to design data models fitted to their specific needs while keeping general classification information for generic use. On the other hand, object oriented concepts have evolved in the software technology domain, and UML has emerged as the most important standard to specify software-based systems. Given the similarities between the goals of ODS and aspects of UML that describe the static parts of a software system, this paper proposes a mapping between these two technologies.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133121759","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505906
M. Aguirre, M. A. Engelhardt, J. Bracco, M. Valla
Multilevel converters constitute a high performance and high reliability option for industrial applications such as motor control, transmission and distribution electrical systems, and interface with alternative energy sources and non-conventional storage systems. The biggest challenge about multilevel topologies is the balance of dividing reactive components (capacitors in voltage converters, and inductors in current converters). In this paper, two methods to force current balance in a Multilevel Current Source Inverter (MCSI) are presented. Both require minimum computing power with excellent closed loop dynamic response.
{"title":"Current balance control in a multilevel current source inverter","authors":"M. Aguirre, M. A. Engelhardt, J. Bracco, M. Valla","doi":"10.1109/ICIT.2013.6505906","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505906","url":null,"abstract":"Multilevel converters constitute a high performance and high reliability option for industrial applications such as motor control, transmission and distribution electrical systems, and interface with alternative energy sources and non-conventional storage systems. The biggest challenge about multilevel topologies is the balance of dividing reactive components (capacitors in voltage converters, and inductors in current converters). In this paper, two methods to force current balance in a Multilevel Current Source Inverter (MCSI) are presented. Both require minimum computing power with excellent closed loop dynamic response.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114598761","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505650
H. Halfar
In this paper, a general purpose inverse kinematics algorithm is proposed. First, an introduction into the topic and an overview over the recent research about this topic is given. The proposed inverse kinematics approach, divided into a configuration and calculation part, is described. Finally, results of a example experiment and some estimations about the accuracy as well as a conclusion is given.
{"title":"General purpose inverse kinematics using lookup-tables","authors":"H. Halfar","doi":"10.1109/ICIT.2013.6505650","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505650","url":null,"abstract":"In this paper, a general purpose inverse kinematics algorithm is proposed. First, an introduction into the topic and an overview over the recent research about this topic is given. The proposed inverse kinematics approach, divided into a configuration and calculation part, is described. Finally, results of a example experiment and some estimations about the accuracy as well as a conclusion is given.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114754159","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505975
Julian A. Fernandez, Seddik Bacha, Delphine Riu, H. Turker, Marc Paupert
A method to reduce the current three phase unbalance using single phase Plug-in Hybrid Electric Vehicle (PHEV) chargers is presented in this paper. A reduction in the voltage unbalance has been achieved as a consequence of the mitigation of the current unbalance. The method performs the reactive power management on the PHEV charger in order to reduce the unbalance factor without affecting the battery charging time or charging power. The method works under restrictions to preserve the voltage quality. A simulation on Matlab-Simulink® of a three phase housing group with power profiles, initial states of charge, charging start time and PHEV category randomly selected is presented. A reduction of 50 % at some times in the day is illustrated.
{"title":"Current unbalance reduction in three-phase systems using single phase PHEV chargers","authors":"Julian A. Fernandez, Seddik Bacha, Delphine Riu, H. Turker, Marc Paupert","doi":"10.1109/ICIT.2013.6505975","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505975","url":null,"abstract":"A method to reduce the current three phase unbalance using single phase Plug-in Hybrid Electric Vehicle (PHEV) chargers is presented in this paper. A reduction in the voltage unbalance has been achieved as a consequence of the mitigation of the current unbalance. The method performs the reactive power management on the PHEV charger in order to reduce the unbalance factor without affecting the battery charging time or charging power. The method works under restrictions to preserve the voltage quality. A simulation on Matlab-Simulink® of a three phase housing group with power profiles, initial states of charge, charging start time and PHEV category randomly selected is presented. A reduction of 50 % at some times in the day is illustrated.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117262698","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505687
F. Alrifai
Closed-loop torque and speed control of the brushless permanent magnet (BLPM) machine requires rotor positional information to control the associated power electronic inverter. Rotor position information is acquired by position sensors or position sensorless schemes. These position sensors increase the cost and size of the BLPM drive systems and make it prone to mechanical failure due to the sensitive nature of typical rotor position sensing devices. Many researchers are investigating position sensorless schemes to address these points, however most position sensorless techniques behave poorly at stand-still and low speeds (0-300rpm); they also behave poorly due to the fact that they estimate load torque which can be difficult in undefined load applications due to control parameter changes. This paper proposes a novel idea to achieve closed-loop control of a BLPM machine by using measured shaft torque feedback from an integrated, low-cost, torque surface acoustic torque (SAW) transducer.
{"title":"Control of a BLPM machine using an integrated torque sensor in place of a rotor position sensor","authors":"F. Alrifai","doi":"10.1109/ICIT.2013.6505687","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505687","url":null,"abstract":"Closed-loop torque and speed control of the brushless permanent magnet (BLPM) machine requires rotor positional information to control the associated power electronic inverter. Rotor position information is acquired by position sensors or position sensorless schemes. These position sensors increase the cost and size of the BLPM drive systems and make it prone to mechanical failure due to the sensitive nature of typical rotor position sensing devices. Many researchers are investigating position sensorless schemes to address these points, however most position sensorless techniques behave poorly at stand-still and low speeds (0-300rpm); they also behave poorly due to the fact that they estimate load torque which can be difficult in undefined load applications due to control parameter changes. This paper proposes a novel idea to achieve closed-loop control of a BLPM machine by using measured shaft torque feedback from an integrated, low-cost, torque surface acoustic torque (SAW) transducer.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115777441","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505958
Saurabh Pal, Srabasti Mukherjee, Prasenjit Choudhury, Subrata Nandi, N. Debnath
The rapid development of mobile communication technology leads to a new style of learning - `m-learning'. The demand of personalized learning through mobile devices creates a new paradigm in education system. The benefits and features of m-learning extend its applicability from distance education to supplementary aid for conventional classroom learning. The paper discusses the necessity, challenges and opportunities of using m-learning in university campus as an aid to conventional learning. A conceptual model is presented for implementing m-learning in university campus along with existing e-learning system.
{"title":"M - learning in university campus scenario - Design and implementation issues","authors":"Saurabh Pal, Srabasti Mukherjee, Prasenjit Choudhury, Subrata Nandi, N. Debnath","doi":"10.1109/ICIT.2013.6505958","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505958","url":null,"abstract":"The rapid development of mobile communication technology leads to a new style of learning - `m-learning'. The demand of personalized learning through mobile devices creates a new paradigm in education system. The benefits and features of m-learning extend its applicability from distance education to supplementary aid for conventional classroom learning. The paper discusses the necessity, challenges and opportunities of using m-learning in university campus as an aid to conventional learning. A conceptual model is presented for implementing m-learning in university campus along with existing e-learning system.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115124736","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505648
A. Agrawal, B. Prasad, V. Viswanathan, S. K. Panda
Under-water exploration and surveillance requires a significant amount of onboard power for unmanned underwater vehicles (UUVs). The main focus of researchers and scientists is to design small, versatile UUVs, which can relax the power requirement onboard and hence increase the mission time. The paper proposes to develop a spherical underwater robot that can employ a docking or soft grounding behavior. To obtain this mechanism the spherical underwater robot should have the capability of self-ballast. By optimally positioning itself and sitting on the bottom, the spherical underwater robot can be placed in sleep mode, with only monitoring sensors awake, thereby harvesting power from the water current through dynamo based rotor blades. After the evaluation of different depth control strategies and research for commercially available UUVs, a concept was found by several comparisons. A diving system has been designed, built and implemented. Additionally, a dynamic model of the diving system has been developed and tested, allowing variable depth control. A Spherical Underwater Robot (SUR) is designed to perform test runs in a test pool. The development of the dynamic model is carried out by a simulation implemented in the MATLAB/Simulink software platform. Experimental test were conducted to validate the dynamic model.
{"title":"Dynamic modeling of variable ballast tank for spherical underwater robot","authors":"A. Agrawal, B. Prasad, V. Viswanathan, S. K. Panda","doi":"10.1109/ICIT.2013.6505648","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505648","url":null,"abstract":"Under-water exploration and surveillance requires a significant amount of onboard power for unmanned underwater vehicles (UUVs). The main focus of researchers and scientists is to design small, versatile UUVs, which can relax the power requirement onboard and hence increase the mission time. The paper proposes to develop a spherical underwater robot that can employ a docking or soft grounding behavior. To obtain this mechanism the spherical underwater robot should have the capability of self-ballast. By optimally positioning itself and sitting on the bottom, the spherical underwater robot can be placed in sleep mode, with only monitoring sensors awake, thereby harvesting power from the water current through dynamo based rotor blades. After the evaluation of different depth control strategies and research for commercially available UUVs, a concept was found by several comparisons. A diving system has been designed, built and implemented. Additionally, a dynamic model of the diving system has been developed and tested, allowing variable depth control. A Spherical Underwater Robot (SUR) is designed to perform test runs in a test pool. The development of the dynamic model is carried out by a simulation implemented in the MATLAB/Simulink software platform. Experimental test were conducted to validate the dynamic model.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115136253","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505897
A. Wessels, L. Pretorius
The aim of this paper is to identify and analyze the impact of a design change in a concurrent systems engineering environment. A mathematical model has been developed to quantify the impact of a design change on a multi-layer, multi-component system. This model confirms that the system hierarchy design is very important to minimize the impact and subsequent development project risk should a design change be required for one of the system components. The mathematical model shows that a design change often has a detrimental effect on project cost and schedule due to the ripple effect of forced design changes to all other functionally coupled system elements. In practice, design modifications/changes particularly during system integration of a complex multi-hierarchical system are virtually unavoidable. The impact of forced changes can only be improved by optimizing the system architecture to keep the system data content or functional couplings to a minimum. The actual impact of a design change in a real system under development can by means of the model be calculated in order to assess the feasibility of allowing the design change or to rather look for alternative lesser development project intrusive solutions to the problem at hand. The model shows that early system engineering to optimize the system architecture with the objective of reducing the system information content is beneficial. This will reduce development project risk as result of unexpected forced design changes in a concurrent engineering development environment. The paper shows that in order to reduce system development project risk, it is important to minimise the system data content (functional couplings) and mature each system element design before integration.
{"title":"The impact of a design change in an engineering development environment: A case study","authors":"A. Wessels, L. Pretorius","doi":"10.1109/ICIT.2013.6505897","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505897","url":null,"abstract":"The aim of this paper is to identify and analyze the impact of a design change in a concurrent systems engineering environment. A mathematical model has been developed to quantify the impact of a design change on a multi-layer, multi-component system. This model confirms that the system hierarchy design is very important to minimize the impact and subsequent development project risk should a design change be required for one of the system components. The mathematical model shows that a design change often has a detrimental effect on project cost and schedule due to the ripple effect of forced design changes to all other functionally coupled system elements. In practice, design modifications/changes particularly during system integration of a complex multi-hierarchical system are virtually unavoidable. The impact of forced changes can only be improved by optimizing the system architecture to keep the system data content or functional couplings to a minimum. The actual impact of a design change in a real system under development can by means of the model be calculated in order to assess the feasibility of allowing the design change or to rather look for alternative lesser development project intrusive solutions to the problem at hand. The model shows that early system engineering to optimize the system architecture with the objective of reducing the system information content is beneficial. This will reduce development project risk as result of unexpected forced design changes in a concurrent engineering development environment. The paper shows that in order to reduce system development project risk, it is important to minimise the system data content (functional couplings) and mature each system element design before integration.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"281 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124500909","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 : 2013-04-23DOI: 10.1109/ICIT.2013.6505769
A. Spies, M. Kamper
In this paper a possible reactive power control method is developed for the direct-drive direct-grid connected slip permanent magnet wind generator. By using a solid-state-assisted on-load tap changer transformer, the terminal voltage of the generator can be varied. In this way the generator can be operated in over- or under-excited mode, allowing for discreet control over the reactive power output of the generator. Solid-state switches are used in the transformer switchgear to increase the lifetime of the diverter circuit. Along with the transformer, two small capacitor banks are also used to deliver additional reactive power when needed. The performance of the system is simulated and the results are evaluated against the grid code specifications of the National Energy Regulator of South Africa.
{"title":"Reactive power control of a direct grid connected slip synchronous permanent magnet wind generator","authors":"A. Spies, M. Kamper","doi":"10.1109/ICIT.2013.6505769","DOIUrl":"https://doi.org/10.1109/ICIT.2013.6505769","url":null,"abstract":"In this paper a possible reactive power control method is developed for the direct-drive direct-grid connected slip permanent magnet wind generator. By using a solid-state-assisted on-load tap changer transformer, the terminal voltage of the generator can be varied. In this way the generator can be operated in over- or under-excited mode, allowing for discreet control over the reactive power output of the generator. Solid-state switches are used in the transformer switchgear to increase the lifetime of the diverter circuit. Along with the transformer, two small capacitor banks are also used to deliver additional reactive power when needed. The performance of the system is simulated and the results are evaluated against the grid code specifications of the National Energy Regulator of South Africa.","PeriodicalId":192784,"journal":{"name":"2013 IEEE International Conference on Industrial Technology (ICIT)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122662011","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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