Pub Date : 2014-05-22DOI: 10.1109/OPTIM.2014.6850892
M. Sack, G. Mueller
Over-voltage triggering is a trigger method for Marx generators, which omits additional wear of electrode. Hence, it is suitable for triggered long-term operation of Marx generators in industrial applications as for example electroporation of plant cells in large scale. The trigger device replaces one or both charging coils between the 1st and 2nd stage of the Marx generator and superimposes an over-voltage to the 1st stage's spark gap. The device is powered by the charging current of the Marx generator. The design of an existing compact trigger device has a shortcoming concerning the scalability in order to adapt it to different Marx generator designs. Hence, a modular trigger device has been developed. This device consists of stacked stages, which enables scaling more easily. A 20-stage device has been built and successfully tested. The paper describes some design issues and testing of the modular trigger device.
{"title":"Testing of a modular over-voltage trigger device for marx generators","authors":"M. Sack, G. Mueller","doi":"10.1109/OPTIM.2014.6850892","DOIUrl":"https://doi.org/10.1109/OPTIM.2014.6850892","url":null,"abstract":"Over-voltage triggering is a trigger method for Marx generators, which omits additional wear of electrode. Hence, it is suitable for triggered long-term operation of Marx generators in industrial applications as for example electroporation of plant cells in large scale. The trigger device replaces one or both charging coils between the 1st and 2nd stage of the Marx generator and superimposes an over-voltage to the 1st stage's spark gap. The device is powered by the charging current of the Marx generator. The design of an existing compact trigger device has a shortcoming concerning the scalability in order to adapt it to different Marx generator designs. Hence, a modular trigger device has been developed. This device consists of stacked stages, which enables scaling more easily. A 20-stage device has been built and successfully tested. The paper describes some design issues and testing of the modular trigger device.","PeriodicalId":298237,"journal":{"name":"2014 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM)","volume":"207 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121094901","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 : 2014-05-22DOI: 10.1109/OPTIM.2014.6850971
I. Peter, G. Scutaru, C. Nistor
As it is known, the induction motors with squirrel cage rotor are classified according to IEC 60034-30:2008 in three efficiency classes: a. Standard Efficiency IE1; b. High Efficiency IE2; c. Premium Efficiency IE3. According to the ecodesign requirements, since 01.01.2015 respectively 01.01.2017 motors shall not be less efficient than IE3 efficiency level. The motor manufacturers are obliged to comply with this requirement, developing the IE3 variant. This paper refers to the mode of execution of these motors, to the applied technical solutions and to the obtained results.
{"title":"Manufacturing of asynchronous motors with squirrel cage rotor, included in the premium efficiency category IE3, at S.C. Electroprecizia Electrical-Motors S.R.L. Săcele","authors":"I. Peter, G. Scutaru, C. Nistor","doi":"10.1109/OPTIM.2014.6850971","DOIUrl":"https://doi.org/10.1109/OPTIM.2014.6850971","url":null,"abstract":"As it is known, the induction motors with squirrel cage rotor are classified according to IEC 60034-30:2008 in three efficiency classes: a. Standard Efficiency IE1; b. High Efficiency IE2; c. Premium Efficiency IE3. According to the ecodesign requirements, since 01.01.2015 respectively 01.01.2017 motors shall not be less efficient than IE3 efficiency level. The motor manufacturers are obliged to comply with this requirement, developing the IE3 variant. This paper refers to the mode of execution of these motors, to the applied technical solutions and to the obtained results.","PeriodicalId":298237,"journal":{"name":"2014 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115834084","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 : 2014-05-22DOI: 10.1109/OPTIM.2014.6850899
L. Mandache, M. Iordache, L. Dumitriu, I. Sirbu, D. Niculae
The paper presents an improvement of sensitivity analysis methods of analog lumped circuits. A practical and reliable approach has been developed and implemented in a computation program intended for linear and/or piecewise-linear approximation of the nonlinear RLCM circuits containing any type of passive elements, independent and controlled sources. A powerful modified nodal approach to build the mathematical model combined with some symbolic computation strategies has been exploited, in order to reduce the computational effort and to minimize the numerical errors. The developed software tool is conceived as a useful and valuable support for research and design engineers.
{"title":"Sensitivity analysis of analog circuits based on a modified nodal approach","authors":"L. Mandache, M. Iordache, L. Dumitriu, I. Sirbu, D. Niculae","doi":"10.1109/OPTIM.2014.6850899","DOIUrl":"https://doi.org/10.1109/OPTIM.2014.6850899","url":null,"abstract":"The paper presents an improvement of sensitivity analysis methods of analog lumped circuits. A practical and reliable approach has been developed and implemented in a computation program intended for linear and/or piecewise-linear approximation of the nonlinear RLCM circuits containing any type of passive elements, independent and controlled sources. A powerful modified nodal approach to build the mathematical model combined with some symbolic computation strategies has been exploited, in order to reduce the computational effort and to minimize the numerical errors. The developed software tool is conceived as a useful and valuable support for research and design engineers.","PeriodicalId":298237,"journal":{"name":"2014 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127424708","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 : 2014-05-22DOI: 10.1109/OPTIM.2014.6850980
Niculai Stanciu, C. Stanescu, W. Szabo, I. Dobre
Measurement results used for Power Quality assessment give an objective evaluation if their trust level is high. This requirement becomes feasible if a system for ensuring measurement quality is already in place and it is adapted to measurements specific domain. The system for ensuring measurement quality is absolutely necessary when measurement results are used to take correct decisions. Because all measurements are accompanied by errors and measurement uncertainty the results are expressed taking into account a certain probability. Sometimes this probability presents a risk if it's not high enough. This article presents some aspects which can contribute to diminish the risk when PQ measurements are validated.
{"title":"Risk minimizing for power quality measurements. A study case","authors":"Niculai Stanciu, C. Stanescu, W. Szabo, I. Dobre","doi":"10.1109/OPTIM.2014.6850980","DOIUrl":"https://doi.org/10.1109/OPTIM.2014.6850980","url":null,"abstract":"Measurement results used for Power Quality assessment give an objective evaluation if their trust level is high. This requirement becomes feasible if a system for ensuring measurement quality is already in place and it is adapted to measurements specific domain. The system for ensuring measurement quality is absolutely necessary when measurement results are used to take correct decisions. Because all measurements are accompanied by errors and measurement uncertainty the results are expressed taking into account a certain probability. Sometimes this probability presents a risk if it's not high enough. This article presents some aspects which can contribute to diminish the risk when PQ measurements are validated.","PeriodicalId":298237,"journal":{"name":"2014 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122324571","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 : 2014-05-22DOI: 10.1109/OPTIM.2014.6850936
Ana-Irina Stan, M. Swierczynski, D. Stroe, R. Teodorescu, S. J. Andreasen
Lithium ion (Li-ion) batteries have been extensively used in consumer electronics because of their characteristics, such as high efficiency, long life, and high gravimetric and volumetric energy. In addition, Li-ion batteries are becoming the most attractive candidate as electrochemical storage systems for stationary applications, as well as power source for sustainable automotive and back-up power supply applications. This paper gives an overview of the Li-ion battery chemistries that are available at present in the market, and describes the three out of four main applications (except the consumers' applications), grid support, automotive, and back-up power, for which the Li-ion batteries are suitable. Each of these applications has its own specifications and thus, the chemistry of the Li-ion battery should be chosen to fulfill the requirements of the corresponding application. Consequently, this paper discusses as well, the suitability of the presented Li-ion battery chemistries for different applications.
{"title":"Lithium ion battery chemistries from renewable energy storage to automotive and back-up power applications — An overview","authors":"Ana-Irina Stan, M. Swierczynski, D. Stroe, R. Teodorescu, S. J. Andreasen","doi":"10.1109/OPTIM.2014.6850936","DOIUrl":"https://doi.org/10.1109/OPTIM.2014.6850936","url":null,"abstract":"Lithium ion (Li-ion) batteries have been extensively used in consumer electronics because of their characteristics, such as high efficiency, long life, and high gravimetric and volumetric energy. In addition, Li-ion batteries are becoming the most attractive candidate as electrochemical storage systems for stationary applications, as well as power source for sustainable automotive and back-up power supply applications. This paper gives an overview of the Li-ion battery chemistries that are available at present in the market, and describes the three out of four main applications (except the consumers' applications), grid support, automotive, and back-up power, for which the Li-ion batteries are suitable. Each of these applications has its own specifications and thus, the chemistry of the Li-ion battery should be chosen to fulfill the requirements of the corresponding application. Consequently, this paper discusses as well, the suitability of the presented Li-ion battery chemistries for different applications.","PeriodicalId":298237,"journal":{"name":"2014 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127169510","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 : 2014-05-22DOI: 10.1109/OPTIM.2014.6850974
R. T. Abdulmunam, L. Taha, P. Ivey
In this paper, electrostatic wind energy harvesting using a multi-pole capacitor has been proposed and demonstrated. First, the operation of the harvester and the electrostatic converter is explained. Subsequently, the construction and mathematical modeling of the multi pole capacitor is described to find the amount of harvested energy at various wind speeds. Next, operation of the energy transfer circuit and the controller are presented. Lastly, energy optimization is conducted for the multi poles capacitors. Results of the optimization indicate that the maximum energy can be harvested when the wind speed is 10 m/sec, the battery voltage is 10 V, and the number of capacitors in the array is 20. Furthermore, the amount of harvested energy from wind is sufficient for a successful transmission of many data packets in wireless manner using the RF transmitter.
{"title":"Wind energy harvesting using electrostatic converter for wireless sensor networks","authors":"R. T. Abdulmunam, L. Taha, P. Ivey","doi":"10.1109/OPTIM.2014.6850974","DOIUrl":"https://doi.org/10.1109/OPTIM.2014.6850974","url":null,"abstract":"In this paper, electrostatic wind energy harvesting using a multi-pole capacitor has been proposed and demonstrated. First, the operation of the harvester and the electrostatic converter is explained. Subsequently, the construction and mathematical modeling of the multi pole capacitor is described to find the amount of harvested energy at various wind speeds. Next, operation of the energy transfer circuit and the controller are presented. Lastly, energy optimization is conducted for the multi poles capacitors. Results of the optimization indicate that the maximum energy can be harvested when the wind speed is 10 m/sec, the battery voltage is 10 V, and the number of capacitors in the array is 20. Furthermore, the amount of harvested energy from wind is sufficient for a successful transmission of many data packets in wireless manner using the RF transmitter.","PeriodicalId":298237,"journal":{"name":"2014 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM)","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131970585","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 : 2014-05-22DOI: 10.1109/OPTIM.2014.6851039
V. Delgado‐Gomes, P. Borza
The concept of smart grid has evolved during the last years. Smart grid is now a collection of power devices, Distributed Energy Sources (DES), Renewable Energy Sources (RES), and monitoring devices using Information and Communication Technology (ICT) to interact between them. A proper power network management needs to be resilient, reliable, and redundant to prevent malfunctions in the power network operation. This paper presents a biological approach to manage smart grids using characteristics such as self healing, different types of control strategies (feedback, feed forward), learning algorithms, different types of energetic storage, and a hierarchical architecture. These characteristics are present in living beings and are important in the smart grid management. An analogy between biological systems and technological systems is made and the similarities between these two systems are presented. A particular case of biological approach applicability in a Hybrid Energy Storage System (HESS) is presented to demonstrate how this approach can be scaled from a single energy cell to an entire power network.
{"title":"A biological approach for energy management in smart grids and hybrid energy storage systems","authors":"V. Delgado‐Gomes, P. Borza","doi":"10.1109/OPTIM.2014.6851039","DOIUrl":"https://doi.org/10.1109/OPTIM.2014.6851039","url":null,"abstract":"The concept of smart grid has evolved during the last years. Smart grid is now a collection of power devices, Distributed Energy Sources (DES), Renewable Energy Sources (RES), and monitoring devices using Information and Communication Technology (ICT) to interact between them. A proper power network management needs to be resilient, reliable, and redundant to prevent malfunctions in the power network operation. This paper presents a biological approach to manage smart grids using characteristics such as self healing, different types of control strategies (feedback, feed forward), learning algorithms, different types of energetic storage, and a hierarchical architecture. These characteristics are present in living beings and are important in the smart grid management. An analogy between biological systems and technological systems is made and the similarities between these two systems are presented. A particular case of biological approach applicability in a Hybrid Energy Storage System (HESS) is presented to demonstrate how this approach can be scaled from a single energy cell to an entire power network.","PeriodicalId":298237,"journal":{"name":"2014 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130946227","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 : 2014-05-22DOI: 10.1109/OPTIM.2014.6851008
J. Curély, J. Kliava
We start this article by recalling the main exact results previously obtained for describing the static magnetic properties of 2d square lattices composed of classical spins isotropically coupled between first-nearest neighbors (i.e., showing Heisenberg couplings) [4c]. Near the critical temperature TC = 0 K we give criterions allowing to directly determine the magnetic phases characterizing 2d magnetic compounds described by our microscopic model. We show that there are three distinct regimes: The Renormalized Classical Regime (RCR), the Quantum Disordered Regime (QDR) and the Quantum Critical Regime (QCR). The static properties give a good image of the spin arrangement and thus remain a good starting point for the study of dynamic properties. As a result, inside each of the three regimes, we may derive the corresponding dynamic behaviors. For practical reasons that we shall detail, we restrict our study to the RCR and QCR cases. An experimental test is given for illustrating this theoretical work. We notably show that it allows one to derive the static correlation length which is an important tool for understanding both static and dynamic properties.
{"title":"Dynamic magnetic properties of two-dimensional (2d) classical square heisenberg lattices","authors":"J. Curély, J. Kliava","doi":"10.1109/OPTIM.2014.6851008","DOIUrl":"https://doi.org/10.1109/OPTIM.2014.6851008","url":null,"abstract":"We start this article by recalling the main exact results previously obtained for describing the static magnetic properties of 2d square lattices composed of classical spins isotropically coupled between first-nearest neighbors (i.e., showing Heisenberg couplings) [4c]. Near the critical temperature TC = 0 K we give criterions allowing to directly determine the magnetic phases characterizing 2d magnetic compounds described by our microscopic model. We show that there are three distinct regimes: The Renormalized Classical Regime (RCR), the Quantum Disordered Regime (QDR) and the Quantum Critical Regime (QCR). The static properties give a good image of the spin arrangement and thus remain a good starting point for the study of dynamic properties. As a result, inside each of the three regimes, we may derive the corresponding dynamic behaviors. For practical reasons that we shall detail, we restrict our study to the RCR and QCR cases. An experimental test is given for illustrating this theoretical work. We notably show that it allows one to derive the static correlation length which is an important tool for understanding both static and dynamic properties.","PeriodicalId":298237,"journal":{"name":"2014 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126956635","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 : 2014-05-22DOI: 10.1109/OPTIM.2014.6850884
L. Tutelea, Ana Popa, I. Boldea
The aim of this paper is to introduce - by general analytical nonlinear and then optimal design with vector control a hybrid electric and electric vehicles (HEV/EV) electric propulsion system for 50/100 kW, 1350-7000 rpm (600 Nm peak torque/40 kg) at above 91% overall efficiency 300 Vdc battery for a peak phase current of 520 A. After searching quite a few alternative electric machines the low weight (40 kg) NdFeB (1.1 T) PM-Reluctance synchronous machine with vector control was developed in detail. Finite element validation of flux density, torque, inductances and non-reconfigurable vector control for the entire peak torque (power) very challenging envelope substantiate a moderate cost high performance HEV (EV) drive.
{"title":"50/100 kW, 1350–7000 rpm (600 Nm peak torque, 40 kg) PM assisted Reluctance synchronous machine: Optimal design with FEM validation and vector control","authors":"L. Tutelea, Ana Popa, I. Boldea","doi":"10.1109/OPTIM.2014.6850884","DOIUrl":"https://doi.org/10.1109/OPTIM.2014.6850884","url":null,"abstract":"The aim of this paper is to introduce - by general analytical nonlinear and then optimal design with vector control a hybrid electric and electric vehicles (HEV/EV) electric propulsion system for 50/100 kW, 1350-7000 rpm (600 Nm peak torque/40 kg) at above 91% overall efficiency 300 Vdc battery for a peak phase current of 520 A. After searching quite a few alternative electric machines the low weight (40 kg) NdFeB (1.1 T) PM-Reluctance synchronous machine with vector control was developed in detail. Finite element validation of flux density, torque, inductances and non-reconfigurable vector control for the entire peak torque (power) very challenging envelope substantiate a moderate cost high performance HEV (EV) drive.","PeriodicalId":298237,"journal":{"name":"2014 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115843112","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 : 2014-05-22DOI: 10.1109/OPTIM.2014.6850955
T. Laszlo, C. Geza, Szekely Iuliu
This paper aims to present a comparative study of various digital control methods for DC-DC converters. These control methods uses Digital Potentiometers, Digital Analog Converters or filtered DPWM signals connected in the feedback control loop of a DC-DC converter in order to adjust the output voltage of the converter. The synthesis presents different mathematical models for calculating the optimal component values for each type of control, detailing the most common effects of components value variation over the entire output range of the converter. The results from computer-aided simulations and a series of experimental measurements validate each previously presented mathematical model. In conclusion, the control methods comparison offers some practical advises about the linearity, resolution, code efficiency in real applications.
{"title":"Practical synthesis of various control methods for digitally adjusted DC-DC converters","authors":"T. Laszlo, C. Geza, Szekely Iuliu","doi":"10.1109/OPTIM.2014.6850955","DOIUrl":"https://doi.org/10.1109/OPTIM.2014.6850955","url":null,"abstract":"This paper aims to present a comparative study of various digital control methods for DC-DC converters. These control methods uses Digital Potentiometers, Digital Analog Converters or filtered DPWM signals connected in the feedback control loop of a DC-DC converter in order to adjust the output voltage of the converter. The synthesis presents different mathematical models for calculating the optimal component values for each type of control, detailing the most common effects of components value variation over the entire output range of the converter. The results from computer-aided simulations and a series of experimental measurements validate each previously presented mathematical model. In conclusion, the control methods comparison offers some practical advises about the linearity, resolution, code efficiency in real applications.","PeriodicalId":298237,"journal":{"name":"2014 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123549580","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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