Pub Date : 2011-12-01DOI: 10.1109/ICEAS.2011.6147142
P. Rout, D. P. Acharya
The design of optimal analog and mixed signal (AMS) very large scale integrated circuits (VLSI) with lesser design cycle time is a challenging task for the integrated circuit (IC) designers. Voltage Controlled Oscillator (VCO) is a radio frequency integrated circuit (RFIC) having wide range of applications. This paper presents a new approach to design a ring oscillator (RO) with optimum performance with only one design cycle. The optimal figure of merit performance for a RO with a constraint of achieving a desired centre frequency is observed using a new technique which combines multi-objective optimization with differential evolution (CMODE). The RO is designed by considering the design parameters extracted from constrained CMODE in Cadence Virtuoso analog design environment (ADE) using gpdk090 library. The simulation results are compared with the CMODE predicted indices and are observed to be in good agreement with it. In this work RO circuits with 9 stages of inverters are considered to be designed for 2 GHz centre frequency with the limitations imposed by gpdk090 library. Results of exhaustive simulation and experimental studies for these ROs are presented here to verify the reduced design cycle time and superior performance offered by the proposed design methodology.
{"title":"Design of CMOS ring oscillator using CMODE","authors":"P. Rout, D. P. Acharya","doi":"10.1109/ICEAS.2011.6147142","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147142","url":null,"abstract":"The design of optimal analog and mixed signal (AMS) very large scale integrated circuits (VLSI) with lesser design cycle time is a challenging task for the integrated circuit (IC) designers. Voltage Controlled Oscillator (VCO) is a radio frequency integrated circuit (RFIC) having wide range of applications. This paper presents a new approach to design a ring oscillator (RO) with optimum performance with only one design cycle. The optimal figure of merit performance for a RO with a constraint of achieving a desired centre frequency is observed using a new technique which combines multi-objective optimization with differential evolution (CMODE). The RO is designed by considering the design parameters extracted from constrained CMODE in Cadence Virtuoso analog design environment (ADE) using gpdk090 library. The simulation results are compared with the CMODE predicted indices and are observed to be in good agreement with it. In this work RO circuits with 9 stages of inverters are considered to be designed for 2 GHz centre frequency with the limitations imposed by gpdk090 library. Results of exhaustive simulation and experimental studies for these ROs are presented here to verify the reduced design cycle time and superior performance offered by the proposed design methodology.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121702617","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147186
N. Nayak, S. Routray, P. Rout
This paper presents a robust non linear sliding mode controller(SMC) for VSC-HVDC transmission link in parallel with an AC transmission line connecting a synchronous generator to infinite bus. A non linear sliding mode controller has been proposed to provide voltage support by means of reactive control at both ends; to damp power oscillations and improve transient stability by controlling either active or reactive power, and to control the power flow through the HVDC link. The proposed control scheme is tested under several system disturbances like changes in short-circuit ratio, faults on the converter and inverter buses. Based upon the time domain simulations in MATLAB/SIMULINK environment, the proposed controller is tested and its better performance is shown compare with the PI controllers whose gains are optimized with teaching learning optimization technique. The proposed controller improves voltage stability, damping of power oscillations and transient stability.
{"title":"A robust control strategies to improve transient stability in VSC-HVDC based interconnected power systems","authors":"N. Nayak, S. Routray, P. Rout","doi":"10.1109/ICEAS.2011.6147186","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147186","url":null,"abstract":"This paper presents a robust non linear sliding mode controller(SMC) for VSC-HVDC transmission link in parallel with an AC transmission line connecting a synchronous generator to infinite bus. A non linear sliding mode controller has been proposed to provide voltage support by means of reactive control at both ends; to damp power oscillations and improve transient stability by controlling either active or reactive power, and to control the power flow through the HVDC link. The proposed control scheme is tested under several system disturbances like changes in short-circuit ratio, faults on the converter and inverter buses. Based upon the time domain simulations in MATLAB/SIMULINK environment, the proposed controller is tested and its better performance is shown compare with the PI controllers whose gains are optimized with teaching learning optimization technique. The proposed controller improves voltage stability, damping of power oscillations and transient stability.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122534322","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147079
P. Jena, A. Pradhan
Protection of double circuit line is more complex than the single circuit. Problems associated with directional relaying for double circuit line during close-in fault, cross country fault, load change and with high resistance fault are addressed in this paper. Conventional directional relaying algorithm uses fault voltage and current phasors to derive the decisions and thus, finds its limitation during close-in fault, load change and cross country fault. In this work a directional relaying scheme using fuzzy logic system is proposed for protection of the double circuit line. This paper proposes a solution for directional relaying of double circuit line combining four features. The technique is evaluated using data simulated with EMTDC/PSCAD for a double circuit line and the dynamic performance of the algorithm is also studied.
{"title":"Solution to directional relaying for double circuit line","authors":"P. Jena, A. Pradhan","doi":"10.1109/ICEAS.2011.6147079","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147079","url":null,"abstract":"Protection of double circuit line is more complex than the single circuit. Problems associated with directional relaying for double circuit line during close-in fault, cross country fault, load change and with high resistance fault are addressed in this paper. Conventional directional relaying algorithm uses fault voltage and current phasors to derive the decisions and thus, finds its limitation during close-in fault, load change and cross country fault. In this work a directional relaying scheme using fuzzy logic system is proposed for protection of the double circuit line. This paper proposes a solution for directional relaying of double circuit line combining four features. The technique is evaluated using data simulated with EMTDC/PSCAD for a double circuit line and the dynamic performance of the algorithm is also studied.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127910697","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147205
K. Vaisakh, T. Jyothsna, U. C. Patnaik
The main objective of this paper is to investigate the performance of multiple machines connected to a common bus terminal with that of an equalized generator typically, considered in a power system. A detailed analysis of small signal and transient stability has been carried out to study the effectiveness of the systems in the presence of a non-linear controller and a conventional PSS. The performance of the controllers has been evaluated by carrying out the simulation on a five-machine test system for small and large disturbances. Case study shows that intensity of oscillations has reduced much in the case of multiple machines equipped with the non-linear controllers.
{"title":"Design of nonlinear stabilizers for a power system with multiple machines connected to infinite bus","authors":"K. Vaisakh, T. Jyothsna, U. C. Patnaik","doi":"10.1109/ICEAS.2011.6147205","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147205","url":null,"abstract":"The main objective of this paper is to investigate the performance of multiple machines connected to a common bus terminal with that of an equalized generator typically, considered in a power system. A detailed analysis of small signal and transient stability has been carried out to study the effectiveness of the systems in the presence of a non-linear controller and a conventional PSS. The performance of the controllers has been evaluated by carrying out the simulation on a five-machine test system for small and large disturbances. Case study shows that intensity of oscillations has reduced much in the case of multiple machines equipped with the non-linear controllers.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129922201","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147132
R. Sharma, P. Samantaray, D. Mohanty, P. Rout
The economic and environmental dispatch problem is formulated as a Non-linear constrained multi-objective problem with competing and non-commensurable objectives of fuel cost and emission. This paper presents a new multi-objective differential evolution algorithm. Initially, a non dominated sorting genetic algorithm is employed to obtain a set of pareto solutions followed by Multi-objective differential evolution algorithm and its corresponding set of pareto solution. The proposed algorithm has been tested on a forty unit test system to illustrate the analysis. The results demonstrate the capabilities of the proposed Multi-objective differential evolution technique to generate the set of well-distributed Pareto-optimal solutions and also reflects its superiority in terms of diversity of the pareto-optimal set. The simulation results obtained from the proposed approach are compared with the NSGA-II method.
{"title":"Environmental economic load dispatch using multi-objective differential evolution algorithm","authors":"R. Sharma, P. Samantaray, D. Mohanty, P. Rout","doi":"10.1109/ICEAS.2011.6147132","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147132","url":null,"abstract":"The economic and environmental dispatch problem is formulated as a Non-linear constrained multi-objective problem with competing and non-commensurable objectives of fuel cost and emission. This paper presents a new multi-objective differential evolution algorithm. Initially, a non dominated sorting genetic algorithm is employed to obtain a set of pareto solutions followed by Multi-objective differential evolution algorithm and its corresponding set of pareto solution. The proposed algorithm has been tested on a forty unit test system to illustrate the analysis. The results demonstrate the capabilities of the proposed Multi-objective differential evolution technique to generate the set of well-distributed Pareto-optimal solutions and also reflects its superiority in terms of diversity of the pareto-optimal set. The simulation results obtained from the proposed approach are compared with the NSGA-II method.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127371490","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147216
S. Jena, B. Babu, G. Mishra, A. Naik
The consumption of reactive power is stochastic in nature for the distribution system. This uncertain variation of the reactive power leads to 1) Variation of voltage at the point of common coupling(PCC) 2)Low power factor 3)low efficiency 4) improper utilization of distribution system and 5) loss of synchronism for a grid connected inverter based — distributed generation. Now a day's distributed generation (DG) system uses current regulated PWM voltage-source inverters (VSI) for synchronizing the utility grid with DG source in order to ensure the grid stability. In this paper reactive power compensation based hysteresis controller and adaptive hysteresis controller is analyzed for inverter interfaced DG which can control the active and reactive power independently. The adaptive hysteresis controller can reduce the current harmonic at PCC considerably which ensures lower total harmonic distortion (THD). The performance indices include THD of the grid current, fast current tracking during steady state and transient conditions. The studied system is modeled and simulated in the MATLAB Simulink environment.
{"title":"Reactive power compensation in inverter-interfaced distributed generation","authors":"S. Jena, B. Babu, G. Mishra, A. Naik","doi":"10.1109/ICEAS.2011.6147216","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147216","url":null,"abstract":"The consumption of reactive power is stochastic in nature for the distribution system. This uncertain variation of the reactive power leads to 1) Variation of voltage at the point of common coupling(PCC) 2)Low power factor 3)low efficiency 4) improper utilization of distribution system and 5) loss of synchronism for a grid connected inverter based — distributed generation. Now a day's distributed generation (DG) system uses current regulated PWM voltage-source inverters (VSI) for synchronizing the utility grid with DG source in order to ensure the grid stability. In this paper reactive power compensation based hysteresis controller and adaptive hysteresis controller is analyzed for inverter interfaced DG which can control the active and reactive power independently. The adaptive hysteresis controller can reduce the current harmonic at PCC considerably which ensures lower total harmonic distortion (THD). The performance indices include THD of the grid current, fast current tracking during steady state and transient conditions. The studied system is modeled and simulated in the MATLAB Simulink environment.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122859786","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147215
M. Bavafa
Smart grid is a relatively new term that refers to the application of information technology to power systems. Due to the complexity of such systems, the possibilities have yet to be clearly defined. Smart Grid will be a new way to the development of the power network. In the development of Smart Grid, how to integrate the Renewable Energy and the Distributed Generation (DG) safely and reliably is a problem urgent to be solved. Siting and sizing of DG planning in Smart Grid construction are researched in this paper. A multi-objective optimal model is established and normalized in the DG number, location and individual capacity of uncertainty. The improved Evolutionary programming is used to solve this optimization problem. Finally, the validity of the method proposed in the paper is proved by an example.
{"title":"A new method of Evolutionary programming in DG planning","authors":"M. Bavafa","doi":"10.1109/ICEAS.2011.6147215","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147215","url":null,"abstract":"Smart grid is a relatively new term that refers to the application of information technology to power systems. Due to the complexity of such systems, the possibilities have yet to be clearly defined. Smart Grid will be a new way to the development of the power network. In the development of Smart Grid, how to integrate the Renewable Energy and the Distributed Generation (DG) safely and reliably is a problem urgent to be solved. Siting and sizing of DG planning in Smart Grid construction are researched in this paper. A multi-objective optimal model is established and normalized in the DG number, location and individual capacity of uncertainty. The improved Evolutionary programming is used to solve this optimization problem. Finally, the validity of the method proposed in the paper is proved by an example.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122486963","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147110
A. Mohapatra, M. K. Mallick, B. K. Panigrahi, Z. Cui, S. Hong
In a deregulated power industry, accurate short term load forecasting (STLF) and price forecasting (STPF) is a key issue in daily power market. The load forecasting helps in unit commitment as well as in economic scheduling of the generators. The price forecasting helps an electric utility to make important decisions like generation of electric power, bidding for generation, price switching and infrastructure development. Price forecasting is very much useful for energy suppliers, ISOs and other participants in electric generation, transmission and distribution. This paper presents a hybrid approach for the STLF and STPF. The time series data pertaining to load / price is decomposed into various decomposition levels by the use of Wavelet Transform (WT) and each level obtained by this process is predicted using Artificial Neural Network (ANN). The performance of the proposed hybrid model is validated using New Delhi load data and Ontario electricity price data.
{"title":"A hybrid approach for short term electricity price and load forecasting","authors":"A. Mohapatra, M. K. Mallick, B. K. Panigrahi, Z. Cui, S. Hong","doi":"10.1109/ICEAS.2011.6147110","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147110","url":null,"abstract":"In a deregulated power industry, accurate short term load forecasting (STLF) and price forecasting (STPF) is a key issue in daily power market. The load forecasting helps in unit commitment as well as in economic scheduling of the generators. The price forecasting helps an electric utility to make important decisions like generation of electric power, bidding for generation, price switching and infrastructure development. Price forecasting is very much useful for energy suppliers, ISOs and other participants in electric generation, transmission and distribution. This paper presents a hybrid approach for the STLF and STPF. The time series data pertaining to load / price is decomposed into various decomposition levels by the use of Wavelet Transform (WT) and each level obtained by this process is predicted using Artificial Neural Network (ANN). The performance of the proposed hybrid model is validated using New Delhi load data and Ontario electricity price data.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131831055","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147088
S. Mishra, P. Sekhar
This paper proposes an effective control strategy for a single-stage, three-phase PV system, supplying local load and integrated with the grid. Maximum power tracking is achieved with interleaved inner current control loop and outer voltage control loop. The output of PV generator is processed by the voltage source converter, a well established dc/ac converter. But these converter systems are highly non linear and coupled. Since the conventional PI controller will not give the satisfactory performance for the changing operating conditions and uncertain load changes, the feedback linearization scheme has been formulated. Sliding mode control technique has been incorporated in the feedback linearized control to address the issues of uncertainty and to add robustness to the control algorithm. The developed control algorithm is tested for the maximum power extraction at different insolations, controlling the dc/ac converter as an ancillary service to supply reactive power, load uncertainties and finally for variable grid frequency within a small band.
{"title":"Sliding mode based feedback linearizing controller for a PV system to improve the performance under grid frequency variation","authors":"S. Mishra, P. Sekhar","doi":"10.1109/ICEAS.2011.6147088","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147088","url":null,"abstract":"This paper proposes an effective control strategy for a single-stage, three-phase PV system, supplying local load and integrated with the grid. Maximum power tracking is achieved with interleaved inner current control loop and outer voltage control loop. The output of PV generator is processed by the voltage source converter, a well established dc/ac converter. But these converter systems are highly non linear and coupled. Since the conventional PI controller will not give the satisfactory performance for the changing operating conditions and uncertain load changes, the feedback linearization scheme has been formulated. Sliding mode control technique has been incorporated in the feedback linearized control to address the issues of uncertainty and to add robustness to the control algorithm. The developed control algorithm is tested for the maximum power extraction at different insolations, controlling the dc/ac converter as an ancillary service to supply reactive power, load uncertainties and finally for variable grid frequency within a small band.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122547240","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 : 2011-12-01DOI: 10.1109/ICEAS.2011.6147139
P. M. Pradhan
A cognitive radio engine adapts its radio parameters using metaheauristic learning algorithms in order to satisfy certain objectives in a radio environment. In this study, three evolutionary algorithms are used for optimizing the predefined fitness functions in the time varying wireless environment. The performances of genetic algorithm, particle swarm optimization and artificial bee colony algorithm are analysed in different modes of operation and in presence of spectral interference. The simulation results are compared using convergence characteristics and two statistical metrics.
{"title":"Design of cognitive radio engine using artificial bee colony algorithm","authors":"P. M. Pradhan","doi":"10.1109/ICEAS.2011.6147139","DOIUrl":"https://doi.org/10.1109/ICEAS.2011.6147139","url":null,"abstract":"A cognitive radio engine adapts its radio parameters using metaheauristic learning algorithms in order to satisfy certain objectives in a radio environment. In this study, three evolutionary algorithms are used for optimizing the predefined fitness functions in the time varying wireless environment. The performances of genetic algorithm, particle swarm optimization and artificial bee colony algorithm are analysed in different modes of operation and in presence of spectral interference. The simulation results are compared using convergence characteristics and two statistical metrics.","PeriodicalId":273164,"journal":{"name":"2011 International Conference on Energy, Automation and Signal","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121446000","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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