Pub Date : 2017-11-01DOI: 10.1109/APPEEC.2017.8309003
Manish Kumar, Y. N. Babu, D. Pullaguram, S. Mishra
A high voltage gain non-isolated three-port DC/DC converter (TPC) is proposed in this paper. Integrated Boost-Cuk topology is modified to a TPC based on dual input converter (DIC) to serve as an interface among a photovoltaic (PV) panel port, a battery port and a load port of a standalone PV system. Principle of operation and a detailed analysis of power flow under different modes is also discussed. The output voltage relation with duty cycle of three switches under various modes of operation is also deduced. The proposed TPC has low voltage stress across the switches. The control algorithm for simultaneously obtaining maximum power point tracking and output voltage regulation is also presented. Simulation is carried out in PSIM with parameters of Kyocera KD215GX 215-W PV panel to validate the control algorithm and high voltage conversion ratio.
{"title":"A high voltage gain non-isolated modified three-port DC/DC converter based on integrated Boost-Cuk topology","authors":"Manish Kumar, Y. N. Babu, D. Pullaguram, S. Mishra","doi":"10.1109/APPEEC.2017.8309003","DOIUrl":"https://doi.org/10.1109/APPEEC.2017.8309003","url":null,"abstract":"A high voltage gain non-isolated three-port DC/DC converter (TPC) is proposed in this paper. Integrated Boost-Cuk topology is modified to a TPC based on dual input converter (DIC) to serve as an interface among a photovoltaic (PV) panel port, a battery port and a load port of a standalone PV system. Principle of operation and a detailed analysis of power flow under different modes is also discussed. The output voltage relation with duty cycle of three switches under various modes of operation is also deduced. The proposed TPC has low voltage stress across the switches. The control algorithm for simultaneously obtaining maximum power point tracking and output voltage regulation is also presented. Simulation is carried out in PSIM with parameters of Kyocera KD215GX 215-W PV panel to validate the control algorithm and high voltage conversion ratio.","PeriodicalId":247669,"journal":{"name":"2017 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130334738","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 : 2017-11-01DOI: 10.1109/APPEEC.2017.8308909
Deepro Sen, P. Acharjee
This paper employs a hybridization of cuckoo search algorithm (CSA) and chemical reaction optimization (CRO) for determining the optimal location of a unified power flow controller (UPFC) in the standard IEEE 30-bus power system network operating under arbitrarily increased load in random load buses to simulate the unpredictability and challenges of a power system transmission network. Lévy Flight and Random Walk techniques of the CSA are used with the collision techniques of CRO in such a way that, in each iteration, a balance is maintained between exploration and exploitation. The proposed algorithm is applied to determine the UPFC location in the system based on voltage quality, active and reactive power losses and installation cost. The results obtained show that the proposed algorithm is adept in handling non-linear and non-convex optimization problems within the boundaries of various equality and inequality constraints of the system as well as that of the UPFC.
{"title":"Optimal placement of UPFC based on techno-economic criteria by hybrid CSA-CRO algorithm","authors":"Deepro Sen, P. Acharjee","doi":"10.1109/APPEEC.2017.8308909","DOIUrl":"https://doi.org/10.1109/APPEEC.2017.8308909","url":null,"abstract":"This paper employs a hybridization of cuckoo search algorithm (CSA) and chemical reaction optimization (CRO) for determining the optimal location of a unified power flow controller (UPFC) in the standard IEEE 30-bus power system network operating under arbitrarily increased load in random load buses to simulate the unpredictability and challenges of a power system transmission network. Lévy Flight and Random Walk techniques of the CSA are used with the collision techniques of CRO in such a way that, in each iteration, a balance is maintained between exploration and exploitation. The proposed algorithm is applied to determine the UPFC location in the system based on voltage quality, active and reactive power losses and installation cost. The results obtained show that the proposed algorithm is adept in handling non-linear and non-convex optimization problems within the boundaries of various equality and inequality constraints of the system as well as that of the UPFC.","PeriodicalId":247669,"journal":{"name":"2017 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134579562","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 : 2017-11-01DOI: 10.1109/APPEEC.2017.8308953
M. Sruthi, C. Nagamani, G. S. Ilango
Conventional conveyor belts are driven by multiple induction machines having megawatt power ratings and their operation ranges are mostly limited to light loads. The control scheme for such operation is normally open loop V/F control without speed sensors. Under specific load conditions, the energy savings can be obtained by implementing the optimal load sharing among the electrical machines. In this paper, a new algorithm is proposed for optimal load sharing. The proposed algorithm is tested on a 5.5 MW conveyor belt system driven by 3.5 MW and 2 MW induction machines under various loading conditions. The simulation results show a favorable potential of the proposed algorithm for dynamic load sharing in conveyor belt systems.
{"title":"Dynamic load sharing in multi-machine conveyor belt systems","authors":"M. Sruthi, C. Nagamani, G. S. Ilango","doi":"10.1109/APPEEC.2017.8308953","DOIUrl":"https://doi.org/10.1109/APPEEC.2017.8308953","url":null,"abstract":"Conventional conveyor belts are driven by multiple induction machines having megawatt power ratings and their operation ranges are mostly limited to light loads. The control scheme for such operation is normally open loop V/F control without speed sensors. Under specific load conditions, the energy savings can be obtained by implementing the optimal load sharing among the electrical machines. In this paper, a new algorithm is proposed for optimal load sharing. The proposed algorithm is tested on a 5.5 MW conveyor belt system driven by 3.5 MW and 2 MW induction machines under various loading conditions. The simulation results show a favorable potential of the proposed algorithm for dynamic load sharing in conveyor belt systems.","PeriodicalId":247669,"journal":{"name":"2017 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129322057","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 : 2017-11-01DOI: 10.1109/APPEEC.2017.8308932
M. A. Farhan, K. Swarup
Unintentional islanding is a critical issue in the integration of distributed generation to the power distribution network. Islanding detection or anti islanding protection for a distribution generation is important in this regard. The paper proposes a new islanding detection scheme in time domain based on Mathematical morphology. The detection technique uses the Morphological gradient wavelet(MGW) to operate on voltage and current in any phase. The Norm of the voltage and current after passing through the MGW is calculated. This ratio is used as a criteria for detecting an island. Simulations are carried out for different islanding and non islanding events to study the effectiveness of the algorithm.
{"title":"Islanding detection scheme based on morphological wavelets","authors":"M. A. Farhan, K. Swarup","doi":"10.1109/APPEEC.2017.8308932","DOIUrl":"https://doi.org/10.1109/APPEEC.2017.8308932","url":null,"abstract":"Unintentional islanding is a critical issue in the integration of distributed generation to the power distribution network. Islanding detection or anti islanding protection for a distribution generation is important in this regard. The paper proposes a new islanding detection scheme in time domain based on Mathematical morphology. The detection technique uses the Morphological gradient wavelet(MGW) to operate on voltage and current in any phase. The Norm of the voltage and current after passing through the MGW is calculated. This ratio is used as a criteria for detecting an island. Simulations are carried out for different islanding and non islanding events to study the effectiveness of the algorithm.","PeriodicalId":247669,"journal":{"name":"2017 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129520153","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 : 2017-11-01DOI: 10.1109/APPEEC.2017.8308938
Kunqi Jia, G. He, S. Fan, Guoying Lin, Shixiang Lu, Feng Pan
Compared with traditional analyses of automated demand response(ADR) which focus on optimal control strategies of physical system, this paper puts more emphasis on the interdependence and interplay of cyber and physical system in automated residential demand response. A heating project of a school and its control strategy are introduced as a typical scene of automated residential demand response. In order to establish a near real model of the heating project, communication reliability is taken into consideration and the network connectedness is modeled based on graph theory. The wireless channel model considering obstacles is established based on the Motley-Keenan Model and the correlation between receive signal strength index(RSSI) and packet receive rate(PRR) is derived according to experimental data. Then, the impact of the packet loss on the performance of the heating project is presented. To provide a reliable wireless communication network to support the heating project, this paper then proposed a greedy strategy based optimization algorithm of relay node deployment and the simulation results verify that the above algorithm can promote the overall system efficiency.
{"title":"Cyber and physical integration analysis for automated residential demand response in smart grid","authors":"Kunqi Jia, G. He, S. Fan, Guoying Lin, Shixiang Lu, Feng Pan","doi":"10.1109/APPEEC.2017.8308938","DOIUrl":"https://doi.org/10.1109/APPEEC.2017.8308938","url":null,"abstract":"Compared with traditional analyses of automated demand response(ADR) which focus on optimal control strategies of physical system, this paper puts more emphasis on the interdependence and interplay of cyber and physical system in automated residential demand response. A heating project of a school and its control strategy are introduced as a typical scene of automated residential demand response. In order to establish a near real model of the heating project, communication reliability is taken into consideration and the network connectedness is modeled based on graph theory. The wireless channel model considering obstacles is established based on the Motley-Keenan Model and the correlation between receive signal strength index(RSSI) and packet receive rate(PRR) is derived according to experimental data. Then, the impact of the packet loss on the performance of the heating project is presented. To provide a reliable wireless communication network to support the heating project, this paper then proposed a greedy strategy based optimization algorithm of relay node deployment and the simulation results verify that the above algorithm can promote the overall system efficiency.","PeriodicalId":247669,"journal":{"name":"2017 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130505739","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 : 2017-11-01DOI: 10.1109/APPEEC.2017.8308899
Pankaj D. Achlerkar, S. Samantaray, M. Manikandan
This paper presents a method of detecting voltage sag, swell and interruption events based on a signal processing tool viz. variational mode decomposition (VMD). The proposed method is able to keep track of variations in amplitude, phase, frequency and undelivered energy due to such events. Voltage signal is half-wave rectified and then decomposed by VMD to get DC part representing instantaneous amplitude envelope, thereby obtaining start/end times and depth of sag/swell. The phase jump and frequency deviations are observed from instantaneous phase, obtained from analytic signal of VMD mode having center frequency nearer to fundamental. Algorithm is tested for various cases of synthetic and simulated signals in MATLAB/Simulink. Comparative performance with recursive discrete Fourier transform and Hilbert transform based method is demonstrated.
{"title":"Detection of voltage variation events using variational mode decomposition","authors":"Pankaj D. Achlerkar, S. Samantaray, M. Manikandan","doi":"10.1109/APPEEC.2017.8308899","DOIUrl":"https://doi.org/10.1109/APPEEC.2017.8308899","url":null,"abstract":"This paper presents a method of detecting voltage sag, swell and interruption events based on a signal processing tool viz. variational mode decomposition (VMD). The proposed method is able to keep track of variations in amplitude, phase, frequency and undelivered energy due to such events. Voltage signal is half-wave rectified and then decomposed by VMD to get DC part representing instantaneous amplitude envelope, thereby obtaining start/end times and depth of sag/swell. The phase jump and frequency deviations are observed from instantaneous phase, obtained from analytic signal of VMD mode having center frequency nearer to fundamental. Algorithm is tested for various cases of synthetic and simulated signals in MATLAB/Simulink. Comparative performance with recursive discrete Fourier transform and Hilbert transform based method is demonstrated.","PeriodicalId":247669,"journal":{"name":"2017 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"214 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115510014","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 : 2017-11-01DOI: 10.1109/APPEEC.2017.8308987
C. L. Dewangan, S. Singh, S. Chakrabarti
Short-term solar power forecasting is vital for reliable and secure operation of power systems with high PV penetration. This paper implements wavelet neural network (WNN) with Levenberg-Marquardt (LM) training for solar irradiance forecasting for finding the solar power output. It employs wavelets basis as activation functions whose shapes are adaptive in nature. The proposed model has better generalization capability and more accuracy than the conventional sigmoidal neural network (SNN). The outcomes demonstrate that the model can be implemented easily and can enhance the forecasting accuracy.
{"title":"Solar irradiance forecasting using wavelet neural network","authors":"C. L. Dewangan, S. Singh, S. Chakrabarti","doi":"10.1109/APPEEC.2017.8308987","DOIUrl":"https://doi.org/10.1109/APPEEC.2017.8308987","url":null,"abstract":"Short-term solar power forecasting is vital for reliable and secure operation of power systems with high PV penetration. This paper implements wavelet neural network (WNN) with Levenberg-Marquardt (LM) training for solar irradiance forecasting for finding the solar power output. It employs wavelets basis as activation functions whose shapes are adaptive in nature. The proposed model has better generalization capability and more accuracy than the conventional sigmoidal neural network (SNN). The outcomes demonstrate that the model can be implemented easily and can enhance the forecasting accuracy.","PeriodicalId":247669,"journal":{"name":"2017 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123969386","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 : 2017-11-01DOI: 10.1109/APPEEC.2017.8308952
L. Dewangan, H. Bahirat
The integration of renewable energy resources has increased possibility of application of multi terminal direct current (MTDC) system. In this paper, the primary level control of voltage source converter (VSC) and their design method is discussed. The control schemes for the MTDC system such as DC voltage control, voltage margin, droop control, coordinated and distributed DC voltage control are discussed and compared. A four terminal VSC based MTDC system is modeled in PSCAD. The performance of the controllers are compared under step load changes and fault on the DC grid.
{"title":"Comparison of HVDC grid control strategies","authors":"L. Dewangan, H. Bahirat","doi":"10.1109/APPEEC.2017.8308952","DOIUrl":"https://doi.org/10.1109/APPEEC.2017.8308952","url":null,"abstract":"The integration of renewable energy resources has increased possibility of application of multi terminal direct current (MTDC) system. In this paper, the primary level control of voltage source converter (VSC) and their design method is discussed. The control schemes for the MTDC system such as DC voltage control, voltage margin, droop control, coordinated and distributed DC voltage control are discussed and compared. A four terminal VSC based MTDC system is modeled in PSCAD. The performance of the controllers are compared under step load changes and fault on the DC grid.","PeriodicalId":247669,"journal":{"name":"2017 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"146 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122065600","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 : 2017-11-01DOI: 10.1109/APPEEC.2017.8308925
S. Shan, L. Umanand
In this paper, a novel algorithm for the seamless transfer of a three phase utility interactive converter from an autonomous mode to a grid connected mode is proposed. The proposed technique does not make use of any grid detecting and synchronising infrastructure. In this scheme, the angular deviation of the synchronously rotating working frame of the converter with respect to the grid frame is estimated at the instant of transfer. This error is added as a feedback term to the phase locked loop (PLL) to the dynamics of the PLL and enhance the speed of alignment to the grid frame. A hysteresis control scheme based on the d and q axes components of the line currents, initiates the enhancement action. Further, this idea is extended to develop a new scheme for self synchronization of parallel converters without any dedicated infrastructure. The proposed scheme aligns the working frames of the parallel converters to a common working frame which makes the synchronisation possible. A power reference reset control along with the proposed algorithm also ensures the load sharing feature of the parallel converters. The proposed technique is validated by adequate simulation and experimental test results.
{"title":"A novel PLL based algorithm for seamless transfer from autonomous to grid mode for utility interactive converters","authors":"S. Shan, L. Umanand","doi":"10.1109/APPEEC.2017.8308925","DOIUrl":"https://doi.org/10.1109/APPEEC.2017.8308925","url":null,"abstract":"In this paper, a novel algorithm for the seamless transfer of a three phase utility interactive converter from an autonomous mode to a grid connected mode is proposed. The proposed technique does not make use of any grid detecting and synchronising infrastructure. In this scheme, the angular deviation of the synchronously rotating working frame of the converter with respect to the grid frame is estimated at the instant of transfer. This error is added as a feedback term to the phase locked loop (PLL) to the dynamics of the PLL and enhance the speed of alignment to the grid frame. A hysteresis control scheme based on the d and q axes components of the line currents, initiates the enhancement action. Further, this idea is extended to develop a new scheme for self synchronization of parallel converters without any dedicated infrastructure. The proposed scheme aligns the working frames of the parallel converters to a common working frame which makes the synchronisation possible. A power reference reset control along with the proposed algorithm also ensures the load sharing feature of the parallel converters. The proposed technique is validated by adequate simulation and experimental test results.","PeriodicalId":247669,"journal":{"name":"2017 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130412987","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 : 2017-11-01DOI: 10.1109/APPEEC.2017.8308985
Priyabrata Shaw, M. Veerachary
In this paper, a digital single-loop voltage-mode controller (VMC) is designed for the non-isolated fifth-order boost converter, which exhibits low source current ripple. A detailed analysis is performed, in continuous inductor current mode of operation, to obtain the design expressions and relevant differential equations. Later on, a state-space modeling approach is extended to formulate the discrete-time models. A pole placement technique is utilized in the digital controller design to achieve required stability margins. The robustness of the closed-loop controlled system is analyzed using modulus margin (MM) concept. Simulation studies have been conducted to validate the steady-state and transient performances of the digital VMC. To confirm the analytical results, a 12 to 48 V, 25 Watt, 100 kHz prototype is developed and the closed-loop system (CLS) stability is verified for a given range of parameter uncertainties. Both simulation and experimental results depict the efficacy of the controller against source and load disturbances.
{"title":"Analysis and voltage-mode controller design for a single-switch fifth-order boost converter","authors":"Priyabrata Shaw, M. Veerachary","doi":"10.1109/APPEEC.2017.8308985","DOIUrl":"https://doi.org/10.1109/APPEEC.2017.8308985","url":null,"abstract":"In this paper, a digital single-loop voltage-mode controller (VMC) is designed for the non-isolated fifth-order boost converter, which exhibits low source current ripple. A detailed analysis is performed, in continuous inductor current mode of operation, to obtain the design expressions and relevant differential equations. Later on, a state-space modeling approach is extended to formulate the discrete-time models. A pole placement technique is utilized in the digital controller design to achieve required stability margins. The robustness of the closed-loop controlled system is analyzed using modulus margin (MM) concept. Simulation studies have been conducted to validate the steady-state and transient performances of the digital VMC. To confirm the analytical results, a 12 to 48 V, 25 Watt, 100 kHz prototype is developed and the closed-loop system (CLS) stability is verified for a given range of parameter uncertainties. Both simulation and experimental results depict the efficacy of the controller against source and load disturbances.","PeriodicalId":247669,"journal":{"name":"2017 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134174132","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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