Pub Date : 2017-10-01DOI: 10.1109/CERA.2017.8343321
S. Chawda, Parul Mathuria, R. Bhakar, S. Sreekumar, Vivek Prakash, F. Teotia
This work addresses the problem of an electricity retailer who manages two sides of trading; optimal procurement of electricity from wholesale market to minimize the procurement cost and optimal selling price calculation considering a price responsive demand, to maximize revenue. On the procurement side, retailer faces uncertainty of pool electricity price and at sell side, it sets selling price based on the elasticity of its consumer demand. The work contributes by highlighting the impact of demand behavior on a retailer's decision making for different price elasticity and providing informed decision support under pool price uncertainty to address different risk-averse nature of retailers.
{"title":"Retailer risk-based trading decision making model under price responsive demand","authors":"S. Chawda, Parul Mathuria, R. Bhakar, S. Sreekumar, Vivek Prakash, F. Teotia","doi":"10.1109/CERA.2017.8343321","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343321","url":null,"abstract":"This work addresses the problem of an electricity retailer who manages two sides of trading; optimal procurement of electricity from wholesale market to minimize the procurement cost and optimal selling price calculation considering a price responsive demand, to maximize revenue. On the procurement side, retailer faces uncertainty of pool electricity price and at sell side, it sets selling price based on the elasticity of its consumer demand. The work contributes by highlighting the impact of demand behavior on a retailer's decision making for different price elasticity and providing informed decision support under pool price uncertainty to address different risk-averse nature of retailers.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115737681","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343384
Neelam Tyagi, R. Tripathi, A. Chandramouli
In this paper, a new heuristic algorithm is constructed for three machines stochastic flow shop scheduling problem to utilized four parameters simultaneously. The parameters which we have used are probabilistic processing time, transportation times, Job block, and weight of the job. The main objective to construct this algorithm is to obtain the optimal sequence to minimize the makespan, Total utilization times and Total rental cost of the hired machines. A numerical example and Gantt chart is also provided to verify the effectiveness of the developed heuristic algorithm.
{"title":"A new heuristic algorithm for three machines stochstic flow shop scheduling model","authors":"Neelam Tyagi, R. Tripathi, A. Chandramouli","doi":"10.1109/CERA.2017.8343384","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343384","url":null,"abstract":"In this paper, a new heuristic algorithm is constructed for three machines stochastic flow shop scheduling problem to utilized four parameters simultaneously. The parameters which we have used are probabilistic processing time, transportation times, Job block, and weight of the job. The main objective to construct this algorithm is to obtain the optimal sequence to minimize the makespan, Total utilization times and Total rental cost of the hired machines. A numerical example and Gantt chart is also provided to verify the effectiveness of the developed heuristic algorithm.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117004475","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343305
Piyush Sharma, N. Gupta, K. R. Niazi, A. Swarnkar
Modern distribution systems are well equipped with diverse distributed energy resources (DERs), each of them capable of enhancing the reliability and performance of distribution systems to a certain extent. In this context, it is interesting to investigate the impact of network reconfiguration (NR) on further enhancement of these vital objectives for efficient system operation. This paper addresses a thorough investigation of NR for reliability and performance improvement in modern distribution systems considering the presence of shunt capacitors (SCs) and distributed generators (DGs). The complex combinatorial NR problem is solved using a recently developed chemical reaction optimization (CRO) algorithm that efficiently deals with the stringent radiality constraint. The investigations are carried out on benchmark IEEE 33-bus test distribution system and results of the analysis are presented explicitly.
{"title":"Investigation of network reconfiguration on the reliability and performance of distribution systems using CRO","authors":"Piyush Sharma, N. Gupta, K. R. Niazi, A. Swarnkar","doi":"10.1109/CERA.2017.8343305","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343305","url":null,"abstract":"Modern distribution systems are well equipped with diverse distributed energy resources (DERs), each of them capable of enhancing the reliability and performance of distribution systems to a certain extent. In this context, it is interesting to investigate the impact of network reconfiguration (NR) on further enhancement of these vital objectives for efficient system operation. This paper addresses a thorough investigation of NR for reliability and performance improvement in modern distribution systems considering the presence of shunt capacitors (SCs) and distributed generators (DGs). The complex combinatorial NR problem is solved using a recently developed chemical reaction optimization (CRO) algorithm that efficiently deals with the stringent radiality constraint. The investigations are carried out on benchmark IEEE 33-bus test distribution system and results of the analysis are presented explicitly.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128276164","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343339
K. Mathuria, Ikhlaq Hussain, Bhim Singh
This study presents the power quality improvement of distributed network by using robust control algorithm for a three phase grid interfaced single stage solar photovoltaic (PV) system with DSTATCOM (Distribution Static Compensator) capabilities. The functions of robust control algorithm are load balancing, reactive power compensation, power factor correction with active power generation for proposed topology. The perturb and observe algorithm is used to extract maximum power from PV array under variable insolation levels. To adapt with variation in terminal voltage at point of common contact (PCC), PV feed forward term is also added in control algorithm to make less oscillations in grid current. The advantages of control algorithm are robustness, less complex, amplitude and frequency adaptive nature. Test results demonstrate satisfactory response for steady state and dynamic conditions at load unbalancing and variations in insolation level. The distortion in grid currents and voltages are found within limits IEEE-519 standard.
{"title":"Robust control algorithm of grid interfaced solar PV system","authors":"K. Mathuria, Ikhlaq Hussain, Bhim Singh","doi":"10.1109/CERA.2017.8343339","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343339","url":null,"abstract":"This study presents the power quality improvement of distributed network by using robust control algorithm for a three phase grid interfaced single stage solar photovoltaic (PV) system with DSTATCOM (Distribution Static Compensator) capabilities. The functions of robust control algorithm are load balancing, reactive power compensation, power factor correction with active power generation for proposed topology. The perturb and observe algorithm is used to extract maximum power from PV array under variable insolation levels. To adapt with variation in terminal voltage at point of common contact (PCC), PV feed forward term is also added in control algorithm to make less oscillations in grid current. The advantages of control algorithm are robustness, less complex, amplitude and frequency adaptive nature. Test results demonstrate satisfactory response for steady state and dynamic conditions at load unbalancing and variations in insolation level. The distortion in grid currents and voltages are found within limits IEEE-519 standard.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124966473","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343328
A. Kumari, H. C. Verma, A. Baral, S. Chakravorti
This paper provides an analysis of various methods for estimating the remaining life of in-service power transformer. Degree of Polymerization (DP) value is perhaps the most effective parameter for determining the remaining life of an Oil-Impregnated-Paper insulation system. Due to the invasive nature of the test, DP value determination using paper samples is not practically feasible for in-situ transformers. On the other hand, commercial equipment's make it relatively easy to obtain the values of paper-moisture and tanδ. Hence, these parameters have become popular among utilities. In the present paper, paper-moisture and tanδ are used to obtain several important dielectric properties (like tensile strength, Degree of Polymerization, hotspot temperature) which are subsequently used for estimating the remaining life of several real-life power transformers. Efforts are also made to identify the method which is capable of identifying remaining life of power transformer with minimum error.
{"title":"Comparison of different methods available for evaluating remaining life of OIP insulation used in power transformers","authors":"A. Kumari, H. C. Verma, A. Baral, S. Chakravorti","doi":"10.1109/CERA.2017.8343328","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343328","url":null,"abstract":"This paper provides an analysis of various methods for estimating the remaining life of in-service power transformer. Degree of Polymerization (DP) value is perhaps the most effective parameter for determining the remaining life of an Oil-Impregnated-Paper insulation system. Due to the invasive nature of the test, DP value determination using paper samples is not practically feasible for in-situ transformers. On the other hand, commercial equipment's make it relatively easy to obtain the values of paper-moisture and tanδ. Hence, these parameters have become popular among utilities. In the present paper, paper-moisture and tanδ are used to obtain several important dielectric properties (like tensile strength, Degree of Polymerization, hotspot temperature) which are subsequently used for estimating the remaining life of several real-life power transformers. Efforts are also made to identify the method which is capable of identifying remaining life of power transformer with minimum error.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124293810","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343309
Nisarg Brahmbhatt, P. Mann, A. Rawat
In this paper, we propose a simplified way of voice communication over Wireless Local Area Network (WLAN) using Internet Protocol, without using internet connectivity at any end in enclosed system. A voice signal is converted into an electrical signal using a microphone and this analog signal will be converted into a digital signal using appropriate quantization level and sampling rate. This digital data is then transmitted over the WLAN network using internet protocol in certain defined packet size, i.e. 8 bit digital packet. At the receiver's end, packets passed through WLAN are received as is, which are combined and converted back to the transmitted analog signal from transmitter's end. These signals can be combined into sound signal through a speaker connected with receiving computer. This method of communication over internet protocol is generally called VoIP, i.e. Voice over Internet Protocol. This method can replace the current PBX telephonic network inside organizations. The demonstration of this mode of communication has been successfully done on institute WLAN with the VoIP server.
{"title":"Design and implementation of compatible VoIP","authors":"Nisarg Brahmbhatt, P. Mann, A. Rawat","doi":"10.1109/CERA.2017.8343309","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343309","url":null,"abstract":"In this paper, we propose a simplified way of voice communication over Wireless Local Area Network (WLAN) using Internet Protocol, without using internet connectivity at any end in enclosed system. A voice signal is converted into an electrical signal using a microphone and this analog signal will be converted into a digital signal using appropriate quantization level and sampling rate. This digital data is then transmitted over the WLAN network using internet protocol in certain defined packet size, i.e. 8 bit digital packet. At the receiver's end, packets passed through WLAN are received as is, which are combined and converted back to the transmitted analog signal from transmitter's end. These signals can be combined into sound signal through a speaker connected with receiving computer. This method of communication over internet protocol is generally called VoIP, i.e. Voice over Internet Protocol. This method can replace the current PBX telephonic network inside organizations. The demonstration of this mode of communication has been successfully done on institute WLAN with the VoIP server.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131588520","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343392
Gantla Sai Kumar Reddy, H. Nagendrappa
In this paper, a fixed-frequency phase shift control is proposed for a 1-phase series-parallel LCL-T resonant converter. Zero-voltage switching (ZVS) of the inverter switches for wide variations in input voltage and load is achieved by designing the converter to operate in above resonance mode. Steady state approximate AC circuit analysis method is used to analyze the converter with fixed-frequency phase shift control. LCL-T converter offers a built-in protection against short-circuiting of the load. LCL-T converter with fixed-frequency control requires a very small change in phase shift to regulate the output voltage for wide variations in input voltage and load. Due to ZVS for the entire input voltage and load variations, the operating efficiency of the converter is high. A 300 W, DC-DC, LCL-T resonant converter is designed for solar energy generation applications. The performance of the converter with the proposed fixed-frequency phase shift control is studied with PSIM simulations. The theoretical and simulation results are compared and presented.
{"title":"Fixed frequency control of LCL-T resonant power converter with capacitive output filter","authors":"Gantla Sai Kumar Reddy, H. Nagendrappa","doi":"10.1109/CERA.2017.8343392","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343392","url":null,"abstract":"In this paper, a fixed-frequency phase shift control is proposed for a 1-phase series-parallel LCL-T resonant converter. Zero-voltage switching (ZVS) of the inverter switches for wide variations in input voltage and load is achieved by designing the converter to operate in above resonance mode. Steady state approximate AC circuit analysis method is used to analyze the converter with fixed-frequency phase shift control. LCL-T converter offers a built-in protection against short-circuiting of the load. LCL-T converter with fixed-frequency control requires a very small change in phase shift to regulate the output voltage for wide variations in input voltage and load. Due to ZVS for the entire input voltage and load variations, the operating efficiency of the converter is high. A 300 W, DC-DC, LCL-T resonant converter is designed for solar energy generation applications. The performance of the converter with the proposed fixed-frequency phase shift control is studied with PSIM simulations. The theoretical and simulation results are compared and presented.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127812514","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343367
J. Prakash, M. Veerachary
This paper proposes a modified soft-switching scheme for high gain interleaved boost converter. A single auxiliary soft-switching network is capable of providing both zero-voltage and zero-current transitions to the main switches. Moreover, the soft-switching network provides soft turn-OFF of all the diodes(main and auxiliary) and does not impose any extra stresses on the devices. The network provides soft turn-ON and turn-OFF of the auxiliary switch as well. A 12 to 100 V, 100 W, 50 kHz circuit has been simulated to validate the soft transitions of the converter.
{"title":"Modified soft-switching scheme for charge-pump based IDB converter","authors":"J. Prakash, M. Veerachary","doi":"10.1109/CERA.2017.8343367","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343367","url":null,"abstract":"This paper proposes a modified soft-switching scheme for high gain interleaved boost converter. A single auxiliary soft-switching network is capable of providing both zero-voltage and zero-current transitions to the main switches. Moreover, the soft-switching network provides soft turn-OFF of all the diodes(main and auxiliary) and does not impose any extra stresses on the devices. The network provides soft turn-ON and turn-OFF of the auxiliary switch as well. A 12 to 100 V, 100 W, 50 kHz circuit has been simulated to validate the soft transitions of the converter.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114940221","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343347
Rohit Goyal, B. H. Kumar, M. Lokhande
This paper presents the various hybrid switching sequences in space vector modulation method for MulitiLevel Inverter (MLI), which reduce the line RMS current ripple and torque ripple of the PWM inverter-fed AC drives. The line RMS current and the torque ripple depend upon the harmonic distortion of the inverter output line voltage. In SVPWM the quality of the inverter output waveform mainly depends upon the applied switching sequence. By applying combinations of different switching sequence in SVPWM the line RMS current ripple and torque ripple is greatly reduced. The MATLAB/SIMULATIONS of various hybrid switching sequences in space vector modulation are carried out for three-level cascaded H-bridge inverter with induction motor load.
{"title":"Combination of switching sequences in SVPWM to reduce line current ripple for IM drives","authors":"Rohit Goyal, B. H. Kumar, M. Lokhande","doi":"10.1109/CERA.2017.8343347","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343347","url":null,"abstract":"This paper presents the various hybrid switching sequences in space vector modulation method for MulitiLevel Inverter (MLI), which reduce the line RMS current ripple and torque ripple of the PWM inverter-fed AC drives. The line RMS current and the torque ripple depend upon the harmonic distortion of the inverter output line voltage. In SVPWM the quality of the inverter output waveform mainly depends upon the applied switching sequence. By applying combinations of different switching sequence in SVPWM the line RMS current ripple and torque ripple is greatly reduced. The MATLAB/SIMULATIONS of various hybrid switching sequences in space vector modulation are carried out for three-level cascaded H-bridge inverter with induction motor load.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116370460","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 : 2017-10-01DOI: 10.1109/CERA.2017.8343343
Sanjiv Kumar, P. Agarwal
The conventional level shifted triangular carrier (LSTC) based space vector pulse width modulation (SVPWM) scheme for open-end winding induction motor (OWIM) drive produces a better harmonic spectrum than the phase shifted triangular carrier based SVPWM, but it does not generate an even number of level operation which results in increase in switching losses specially at lower speed range. To reduce the switching losses at lower speed range and to get the even number of level operation LSTC based SVPWM scheme is proposed in this paper. To verify the effectiveness of proposed scheme a hardware prototype of 9-level inverter fed 1.5kW OWIM drive is implemented and performance of the drive is evaluated with proposed and conventional level shifted triangular carrier based SVPWM schemes.
{"title":"Performance evaluation of multi-level inverter fed open-end winding IM drive under two different modulation schemes","authors":"Sanjiv Kumar, P. Agarwal","doi":"10.1109/CERA.2017.8343343","DOIUrl":"https://doi.org/10.1109/CERA.2017.8343343","url":null,"abstract":"The conventional level shifted triangular carrier (LSTC) based space vector pulse width modulation (SVPWM) scheme for open-end winding induction motor (OWIM) drive produces a better harmonic spectrum than the phase shifted triangular carrier based SVPWM, but it does not generate an even number of level operation which results in increase in switching losses specially at lower speed range. To reduce the switching losses at lower speed range and to get the even number of level operation LSTC based SVPWM scheme is proposed in this paper. To verify the effectiveness of proposed scheme a hardware prototype of 9-level inverter fed 1.5kW OWIM drive is implemented and performance of the drive is evaluated with proposed and conventional level shifted triangular carrier based SVPWM schemes.","PeriodicalId":286358,"journal":{"name":"2017 6th International Conference on Computer Applications In Electrical Engineering-Recent Advances (CERA)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125794385","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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