Pub Date : 2014-09-11DOI: 10.1109/ICIT.2014.6894957
Jeong-Ho Chang, Heung-Ho Lee, In-soo Kim
For decades DC (Direct Current) has been used to assess the condition of medium and high voltage power cables. There are several advantages using this DC test due to its low weight, portability, usability, and being cost-effective. Meanwhile, this DC method has its limitations including possible destructive consequences [1]. It has caused cable failures due to `charges' trapped in the insulation. This induced local field stress when AC power reenergized and accelerated the growth of water-trees. Therefore, recently the Very Low Frequency (VLF) test has been recommended to use as an installation test of XLPE insulated cables according to IEEE standards. In this paper the VLF cable test will be studied in detail for testing XLPE power cables using the Tan δ and Partial Discharge measurements. The focus is to detect any existing fault, defects, or irregularities at the inspection of the cables before any breakdowns occur. The test data on service aged XLPE cables used in hydro power generators will be analyzed.
{"title":"A study on analysis of defects for hydro generator power transmission cables using VLF testing and diagnostic measurements","authors":"Jeong-Ho Chang, Heung-Ho Lee, In-soo Kim","doi":"10.1109/ICIT.2014.6894957","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894957","url":null,"abstract":"For decades DC (Direct Current) has been used to assess the condition of medium and high voltage power cables. There are several advantages using this DC test due to its low weight, portability, usability, and being cost-effective. Meanwhile, this DC method has its limitations including possible destructive consequences [1]. It has caused cable failures due to `charges' trapped in the insulation. This induced local field stress when AC power reenergized and accelerated the growth of water-trees. Therefore, recently the Very Low Frequency (VLF) test has been recommended to use as an installation test of XLPE insulated cables according to IEEE standards. In this paper the VLF cable test will be studied in detail for testing XLPE power cables using the Tan δ and Partial Discharge measurements. The focus is to detect any existing fault, defects, or irregularities at the inspection of the cables before any breakdowns occur. The test data on service aged XLPE cables used in hydro power generators will be analyzed.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"2010 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127353007","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894985
N. Kumar, T. Saha, J. Dey
In this paper, isolated source cascaded two level inverter (CTLI) has been proposed for grid connected photovoltaic system. The system is operated to supply active power with available solar irradiance and to supply reactive power in absence of it. The conventional CTLI is controlled through vector control topology to provide controlled active and reactive power in the said conditions. The photovoltaic system is modelled and tested with the controlled grid connected CTLI, for solar irradiance variation, and reference reactive power variation in simulation environment. The control scheme has been introduced for dc link voltage of the dual level inverter. The dc link voltage is found to be maintained at required level for both type of power supply.
{"title":"Cascaded two level inverter based grid connected photovoltaic system: Modelling and control","authors":"N. Kumar, T. Saha, J. Dey","doi":"10.1109/ICIT.2014.6894985","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894985","url":null,"abstract":"In this paper, isolated source cascaded two level inverter (CTLI) has been proposed for grid connected photovoltaic system. The system is operated to supply active power with available solar irradiance and to supply reactive power in absence of it. The conventional CTLI is controlled through vector control topology to provide controlled active and reactive power in the said conditions. The photovoltaic system is modelled and tested with the controlled grid connected CTLI, for solar irradiance variation, and reference reactive power variation in simulation environment. The control scheme has been introduced for dc link voltage of the dual level inverter. The dc link voltage is found to be maintained at required level for both type of power supply.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"166 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133791078","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894989
Dong-jo Won, Yong-su Noh, Moo-young Ryu, C. Won, Hong-woo Lim
Because AC module system is directly connected to grid source, power pulsation is appeared at AC module input capacitor. So, it can adversely affect maximum power point tracking (MPPT) control. Furthermore, photovoltaic (PV) module power can be fluctuated with varying irradiation while constant load demand. To reduce power fluctuation for MPPT control and stabilize the PV system with varying conditions, conventional flyback converter has auxiliary circuits for active decoupling and energy storage system (ESS) is proposed for energy efficiency. Proposed AC module system can solve the above problem (i.e. power pulsation, varying irradiation and load demand) by auxiliary circuit operation. But when the proposed AC module system is operating, it has various modes according to power flowing. In this paper, analyzes proposed AC module of operating modes, which show perform the overall system operation. To confirming proposed AC module system, verified by PSIM simulation result.
{"title":"A study of grid-connected PV-AC module with active power decoupling and ESS","authors":"Dong-jo Won, Yong-su Noh, Moo-young Ryu, C. Won, Hong-woo Lim","doi":"10.1109/ICIT.2014.6894989","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894989","url":null,"abstract":"Because AC module system is directly connected to grid source, power pulsation is appeared at AC module input capacitor. So, it can adversely affect maximum power point tracking (MPPT) control. Furthermore, photovoltaic (PV) module power can be fluctuated with varying irradiation while constant load demand. To reduce power fluctuation for MPPT control and stabilize the PV system with varying conditions, conventional flyback converter has auxiliary circuits for active decoupling and energy storage system (ESS) is proposed for energy efficiency. Proposed AC module system can solve the above problem (i.e. power pulsation, varying irradiation and load demand) by auxiliary circuit operation. But when the proposed AC module system is operating, it has various modes according to power flowing. In this paper, analyzes proposed AC module of operating modes, which show perform the overall system operation. To confirming proposed AC module system, verified by PSIM simulation result.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133944212","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894988
Hyun-Chil Choi, M. Ciobotaru, V. Agelidis
The trend associated with the ever increasing size of grid-connected photovoltaic (PV) systems necessitates PV system configurations with higher power rating power processing converters and interconnection at a higher voltage level at the point of common coupling (PCC). Moreover, the inherent intermittency of the solar irradiation greatly affects both transient- and steady-state operation of these ever larger PV systems. This paper proposes a solution dealing with challenges of the large-scale PV system. The paper introduces a multistring PV system configuration based on a high-gain DC/DC converter and energy storage system (ESS). The interleaved structure of the high-gain DC/DC converter can easily handle the challenges regarding the power rating of converters and the requirement of higher voltage at PCC. Moreover, the ESS suppresses the power fluctuation of PV arrays and balances the difference between generated PV power and peak load demand. The simulation results of proposed system are presented to validate the performance of transient and steady state.
{"title":"Large-scale PV systems with energy storage utilizing high-gain DC/DC converters","authors":"Hyun-Chil Choi, M. Ciobotaru, V. Agelidis","doi":"10.1109/ICIT.2014.6894988","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894988","url":null,"abstract":"The trend associated with the ever increasing size of grid-connected photovoltaic (PV) systems necessitates PV system configurations with higher power rating power processing converters and interconnection at a higher voltage level at the point of common coupling (PCC). Moreover, the inherent intermittency of the solar irradiation greatly affects both transient- and steady-state operation of these ever larger PV systems. This paper proposes a solution dealing with challenges of the large-scale PV system. The paper introduces a multistring PV system configuration based on a high-gain DC/DC converter and energy storage system (ESS). The interleaved structure of the high-gain DC/DC converter can easily handle the challenges regarding the power rating of converters and the requirement of higher voltage at PCC. Moreover, the ESS suppresses the power fluctuation of PV arrays and balances the difference between generated PV power and peak load demand. The simulation results of proposed system are presented to validate the performance of transient and steady state.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131472248","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 : 2014-09-11DOI: 10.6113/JPE.2014.14.5.852
Bo Wang, Dong-Hee Lee, Jin-Woo Ahn
Switched reluctance machines with segmental rotors are investigated, base on the traditional radial field magnetic structure, a novel axial field SRM is prototyped. This paper presents a machine topology, which permits the use of short pitched windings placed around a single teeth stator, and with the segmental rotor design, the core loss and weight of the rotor will be reduced. This concept maintains the torque capability of a previous design, but uses much less copper volume. The finite element model is established base on the software of Maxwell 12- 3D, which is aimed at flux linkage, inductance, output torque, radial force and axial force. The theoretical basis for the machine configuration is developed and then the results for a working prototype machine are shown, illustrating static torque and flux linkage profiles. Results are presented for the machine operating as a drive, indicating the viability of the concept which is much suitable for the low speed and high torque application.
{"title":"Characteristic analysis of a novel segmental rotor axial field switched reluctance motor with single teeth winding","authors":"Bo Wang, Dong-Hee Lee, Jin-Woo Ahn","doi":"10.6113/JPE.2014.14.5.852","DOIUrl":"https://doi.org/10.6113/JPE.2014.14.5.852","url":null,"abstract":"Switched reluctance machines with segmental rotors are investigated, base on the traditional radial field magnetic structure, a novel axial field SRM is prototyped. This paper presents a machine topology, which permits the use of short pitched windings placed around a single teeth stator, and with the segmental rotor design, the core loss and weight of the rotor will be reduced. This concept maintains the torque capability of a previous design, but uses much less copper volume. The finite element model is established base on the software of Maxwell 12- 3D, which is aimed at flux linkage, inductance, output torque, radial force and axial force. The theoretical basis for the machine configuration is developed and then the results for a working prototype machine are shown, illustrating static torque and flux linkage profiles. Results are presented for the machine operating as a drive, indicating the viability of the concept which is much suitable for the low speed and high torque application.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134601583","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894866
W. Choi, Jin-Wook Park, Sung‐Jun Park, C. Jin, Dae-Sung Jo
This paper proposes a high efficiency 3[kW] flyback converter with active clamp snubber. The proposed converter comprises of flyback part and active clamp snubber part. The flyback part achieved soft switching which at conventional flyback combined LC snubber. And, the active clamp snubber part applied LLC resonant converter. The leakage inductance of flyback transformer generates additional peak voltage to at both ends of the main switch. The higher voltage at both ends of switch shows higher loss at steady state. The active clamp snubber part removes on generated additional peak voltage by the leakage inductance. As well as, the active clamp snubber pass a portion of the whole output power to load. As a result, the proposed converter can reduce peak voltage stress and current stress at steady state, switching loss. Integrity of the proposed converter is validated using both theoretical analysis and PSIM simulation.
{"title":"A new topology of flyback converter with active clamp snubber for battery application","authors":"W. Choi, Jin-Wook Park, Sung‐Jun Park, C. Jin, Dae-Sung Jo","doi":"10.1109/ICIT.2014.6894866","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894866","url":null,"abstract":"This paper proposes a high efficiency 3[kW] flyback converter with active clamp snubber. The proposed converter comprises of flyback part and active clamp snubber part. The flyback part achieved soft switching which at conventional flyback combined LC snubber. And, the active clamp snubber part applied LLC resonant converter. The leakage inductance of flyback transformer generates additional peak voltage to at both ends of the main switch. The higher voltage at both ends of switch shows higher loss at steady state. The active clamp snubber part removes on generated additional peak voltage by the leakage inductance. As well as, the active clamp snubber pass a portion of the whole output power to load. As a result, the proposed converter can reduce peak voltage stress and current stress at steady state, switching loss. Integrity of the proposed converter is validated using both theoretical analysis and PSIM simulation.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129513494","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894955
M. Ojaghi, M. Azari, A. C. Valujerdi
The main contribution of this paper is to present an optimal solution for under voltage load shedding (UVLS) problem using Hybrid Genetic Algorithm and Particle Swarm Optimization (HGAPSO). The effectiveness of the proposed scheme for optimal procedure is investigated. The above-mentioned problem is converted to an optimization problem with the multi-objective function including the minimum active power losses, the maximum voltage stability, the minimum customer interruption cost and the desired alleviating transmission line under over loading conditions, in which the customer interruption cost is modeled as a quadratic function in five major load classifications on each bus. The effectiveness of the proposed approach is confirmed on IEEE 57 bus test system under different operating conditions. The comparative analysis is made between other evolutionary methods like PSO through some performance indices to demonstrate its flexibility and strong performance.
{"title":"Robust UVLS scheme to improve transmission line performance considering interruption cost and voltage stability index","authors":"M. Ojaghi, M. Azari, A. C. Valujerdi","doi":"10.1109/ICIT.2014.6894955","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894955","url":null,"abstract":"The main contribution of this paper is to present an optimal solution for under voltage load shedding (UVLS) problem using Hybrid Genetic Algorithm and Particle Swarm Optimization (HGAPSO). The effectiveness of the proposed scheme for optimal procedure is investigated. The above-mentioned problem is converted to an optimization problem with the multi-objective function including the minimum active power losses, the maximum voltage stability, the minimum customer interruption cost and the desired alleviating transmission line under over loading conditions, in which the customer interruption cost is modeled as a quadratic function in five major load classifications on each bus. The effectiveness of the proposed approach is confirmed on IEEE 57 bus test system under different operating conditions. The comparative analysis is made between other evolutionary methods like PSO through some performance indices to demonstrate its flexibility and strong performance.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131606376","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6895006
S. W. Ha, J. H. Kim
We introduce the DTM (dynamic genetic tree-map), a self-organizing neural network capable of structuring the optimal features in the data destined for recognition. The DTM uses a genetic algorithm to determine the degree of importance of features that have not been considered in the existing neural network. And we apply the GTM (genetic tree-map) that includes tree structure according to the precedence of the features. We suggest that the neurons inside the neural network are dynamically separated and incorporated based on the extended method of the DTM.
{"title":"Dynamic tree map for video analysis","authors":"S. W. Ha, J. H. Kim","doi":"10.1109/ICIT.2014.6895006","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6895006","url":null,"abstract":"We introduce the DTM (dynamic genetic tree-map), a self-organizing neural network capable of structuring the optimal features in the data destined for recognition. The DTM uses a genetic algorithm to determine the degree of importance of features that have not been considered in the existing neural network. And we apply the GTM (genetic tree-map) that includes tree structure according to the precedence of the features. We suggest that the neurons inside the neural network are dynamically separated and incorporated based on the extended method of the DTM.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"127 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115626237","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894916
J. Kim, J. Jeon, Jae Hak Lee, Bok Sun Yeom
This paper explains a method for migration from RS-485 to EtherCAT for the closed loop step motor drive. Since realtime Ethernet is an alternative for the low speed fieldbus that uses RS-485 or CAN, the low speed fieldbus based legacy system (e.g. RS-485 based motor drive) also needs to support real-time Ethernet. Therefore, migration from the low speed fieldbus to real-time Ethernet becomes more important. In this paper, a migration method from RS-485 to EtherCAT is proposed for the closed loop step motor drive. While this paper explains the migration method from RS-485 to EtherCAT, the method can be applied to a range of migration types, from the low speed fieldbus to real-time Ethernet. The EtherCAT based closed loop step motor drive is developed and performance is analyzed and compared to the RS-485 and Mechatrolink ||| based motor drives.
{"title":"Migration from RS-485 to EtherCAT for closed loop step motor drive","authors":"J. Kim, J. Jeon, Jae Hak Lee, Bok Sun Yeom","doi":"10.1109/ICIT.2014.6894916","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894916","url":null,"abstract":"This paper explains a method for migration from RS-485 to EtherCAT for the closed loop step motor drive. Since realtime Ethernet is an alternative for the low speed fieldbus that uses RS-485 or CAN, the low speed fieldbus based legacy system (e.g. RS-485 based motor drive) also needs to support real-time Ethernet. Therefore, migration from the low speed fieldbus to real-time Ethernet becomes more important. In this paper, a migration method from RS-485 to EtherCAT is proposed for the closed loop step motor drive. While this paper explains the migration method from RS-485 to EtherCAT, the method can be applied to a range of migration types, from the low speed fieldbus to real-time Ethernet. The EtherCAT based closed loop step motor drive is developed and performance is analyzed and compared to the RS-485 and Mechatrolink ||| based motor drives.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123935600","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 : 2014-09-11DOI: 10.1109/ICIT.2014.6894991
Soumik Sen, Kalyan Yenduri, P. Sensarma
This paper proposes a detailed step-by-step design procedure and control of an LCL filter for grid connected three phase sine PWM voltage source inverter. The goal of the design is to ensure high quality of grid current as well as to minimize the size of filter magnetics. In order to ensure unity power factor injection into grid a current controller is designed with a constraint that only the inverter side inductor current is sensed. Good agreement between simulation and experimental results verify the effectiveness of the designed controller and the LCL filter.
{"title":"Step-by-step design and control of LCL filter based three phase grid-connected inverter","authors":"Soumik Sen, Kalyan Yenduri, P. Sensarma","doi":"10.1109/ICIT.2014.6894991","DOIUrl":"https://doi.org/10.1109/ICIT.2014.6894991","url":null,"abstract":"This paper proposes a detailed step-by-step design procedure and control of an LCL filter for grid connected three phase sine PWM voltage source inverter. The goal of the design is to ensure high quality of grid current as well as to minimize the size of filter magnetics. In order to ensure unity power factor injection into grid a current controller is designed with a constraint that only the inverter side inductor current is sensed. Good agreement between simulation and experimental results verify the effectiveness of the designed controller and the LCL filter.","PeriodicalId":240337,"journal":{"name":"2014 IEEE International Conference on Industrial Technology (ICIT)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124265701","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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