Pub Date : 2016-07-17DOI: 10.1109/PESGM.2016.7741942
Y. Y. Chen, J. L. Liao, G. Chang, L. Hsu, Y. Li, H. J. Lu
This paper presents the implementation of power quality (PQ) analysis platform that can access different venders' PQ meter data being translated to Power Quality Data Interchange Format (PQDIF) files and view the data through a LabVIEW-based graphical user interface. The implemented platform also can manage the retrieved PQ data in a customized database. Performance tests show that the implemented system can meet the PQ measurement requirements for smart grid applications.
{"title":"Applying IEEE standard 1159.3 for Power Quality analysis platform implementation","authors":"Y. Y. Chen, J. L. Liao, G. Chang, L. Hsu, Y. Li, H. J. Lu","doi":"10.1109/PESGM.2016.7741942","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741942","url":null,"abstract":"This paper presents the implementation of power quality (PQ) analysis platform that can access different venders' PQ meter data being translated to Power Quality Data Interchange Format (PQDIF) files and view the data through a LabVIEW-based graphical user interface. The implemented platform also can manage the retrieved PQ data in a customized database. Performance tests show that the implemented system can meet the PQ measurement requirements for smart grid applications.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116888861","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741407
Jian Zhao, C. Wan, Zhao Xu, Jiayong Li
With increasingly widespread utilization of photovoltaic (PV) systems, the stochastic characteristics of the PV generation may bring new challenges to security and reliability of the power system operation. This paper proposes a novel spinning reserve requirement optimization model considering the impacts of large-scale photovoltaic generation penetration. The effects of forecast error of PV generation output on the energy not supplied are taken into account in the proposed model. The power system spinning reserve is optimized using a benefit/cost analysis approach to coordinate the costs of generation operation, and the costs of the expected energy not supplied (EENS). The proposed model is illustrated using IEEE reliability test system (RTS-96). Numerical results systematically demonstrate the increase of scheduled spinning reserve and the reduction of EENS via the application of the proposed model. The penetration levels of PV generation in power systems are symmetrically analyzed for future implementation of the proposed model.
{"title":"Impacts of large-scale photovoltaic generation penetration on power system spinning reserve allocation","authors":"Jian Zhao, C. Wan, Zhao Xu, Jiayong Li","doi":"10.1109/PESGM.2016.7741407","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741407","url":null,"abstract":"With increasingly widespread utilization of photovoltaic (PV) systems, the stochastic characteristics of the PV generation may bring new challenges to security and reliability of the power system operation. This paper proposes a novel spinning reserve requirement optimization model considering the impacts of large-scale photovoltaic generation penetration. The effects of forecast error of PV generation output on the energy not supplied are taken into account in the proposed model. The power system spinning reserve is optimized using a benefit/cost analysis approach to coordinate the costs of generation operation, and the costs of the expected energy not supplied (EENS). The proposed model is illustrated using IEEE reliability test system (RTS-96). Numerical results systematically demonstrate the increase of scheduled spinning reserve and the reduction of EENS via the application of the proposed model. The penetration levels of PV generation in power systems are symmetrically analyzed for future implementation of the proposed model.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116010739","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741708
Rahul Kadavil, T. Hansen, S. Suryanarayanan
Performing co-simulation studies on transmission and distribution systems software environments requires linking the transmission system elements in the former with highly detailed distribution network models and probabilistic load models in the latter. This paper presents a two-step algorithm for: (i) creating a scalable distribution system in a bottom-up approach to match the connected load at the transmission system bus; and (ii) populating the distribution system with active power loads possessing time varying load profiles. We demonstrate an application of the algorithm by creating a detailed distribution topology populated with residential loads expanded from a selected transmission node in a standard test system. All codes are written using the Python coding environment.
{"title":"An algorithmic approach for creating diverse stochastic feeder datasets for power systems co-simulations","authors":"Rahul Kadavil, T. Hansen, S. Suryanarayanan","doi":"10.1109/PESGM.2016.7741708","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741708","url":null,"abstract":"Performing co-simulation studies on transmission and distribution systems software environments requires linking the transmission system elements in the former with highly detailed distribution network models and probabilistic load models in the latter. This paper presents a two-step algorithm for: (i) creating a scalable distribution system in a bottom-up approach to match the connected load at the transmission system bus; and (ii) populating the distribution system with active power loads possessing time varying load profiles. We demonstrate an application of the algorithm by creating a detailed distribution topology populated with residential loads expanded from a selected transmission node in a standard test system. All codes are written using the Python coding environment.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116175082","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741829
S. Kulkarni, M. Parimi, S. Wagh, N. Singh
Knowledge of a potential function is of prime importance in stability analysis of systems. In mechanical systems, energy is considered as potential function. Passivity based methods in literature aim in finding potential function, which may prove unsuccessful for certain class of systems e.g. biological systems. Unfortunately, no general rules exist for the construction of a Lyapunov function, so expertise and intuition of the designer on the specific system is required to define a candidate function. Present paper proposes a systematic method to generate a potential function after decomposing a drift vector field representing a general dynamical system. The method finds application in lossy multi-machine systems for deriving a control law using gradient formulation without solving partial differential equations. The results validated on examples in the area of power system are used in transient stability analysis and enhancement.
{"title":"Decomposition of drift vector field: An application to multi-machine transient stability enhancement","authors":"S. Kulkarni, M. Parimi, S. Wagh, N. Singh","doi":"10.1109/PESGM.2016.7741829","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741829","url":null,"abstract":"Knowledge of a potential function is of prime importance in stability analysis of systems. In mechanical systems, energy is considered as potential function. Passivity based methods in literature aim in finding potential function, which may prove unsuccessful for certain class of systems e.g. biological systems. Unfortunately, no general rules exist for the construction of a Lyapunov function, so expertise and intuition of the designer on the specific system is required to define a candidate function. Present paper proposes a systematic method to generate a potential function after decomposing a drift vector field representing a general dynamical system. The method finds application in lossy multi-machine systems for deriving a control law using gradient formulation without solving partial differential equations. The results validated on examples in the area of power system are used in transient stability analysis and enhancement.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"201 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123222792","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741262
Meng Jia, N. Zhou, B. Amidan
The Prony analysis has been considered as a standard method for estimating oscillation modes using ringdown responses in a power grid. Extensive studies have been done to find its optimal performance conditions, but the comparisons between the Prony analysis and other modal analysis approaches from a user perspective are insufficient. This paper compares the performance of two modal analysis methods, i.e., the eigensystem realization algorithm (ERA) and the Prony analysis. Their performances are compared using a simple model and a 16-machine model. The influence of the parameters, such as the model order, the decimation factor, and signal-noise-ratio (SNR), on the modes' estimation accuracy is evaluated. Because of the randomness of noise, the Monte Carlo (MC) method is used to evaluate estimation accuracy. The median absolute deviation (MAD) is used as a metric for comparing the estimation errors. It is shown that the ERA has more preferred features than the Prony analysis in estimating power system modes.
{"title":"A comparative study on the Prony analysis and the ERA for modal analysis","authors":"Meng Jia, N. Zhou, B. Amidan","doi":"10.1109/PESGM.2016.7741262","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741262","url":null,"abstract":"The Prony analysis has been considered as a standard method for estimating oscillation modes using ringdown responses in a power grid. Extensive studies have been done to find its optimal performance conditions, but the comparisons between the Prony analysis and other modal analysis approaches from a user perspective are insufficient. This paper compares the performance of two modal analysis methods, i.e., the eigensystem realization algorithm (ERA) and the Prony analysis. Their performances are compared using a simple model and a 16-machine model. The influence of the parameters, such as the model order, the decimation factor, and signal-noise-ratio (SNR), on the modes' estimation accuracy is evaluated. Because of the randomness of noise, the Monte Carlo (MC) method is used to evaluate estimation accuracy. The median absolute deviation (MAD) is used as a metric for comparing the estimation errors. It is shown that the ERA has more preferred features than the Prony analysis in estimating power system modes.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121995364","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741741
Jagdeep Kaur, Amirthagunaraj Yogarathinam, N. Chaudhuri
Interconnection of DFIG-based wind farms with LCC-HVDC is challenging for very weak AC systems. This work focuses on establishing a modeling and control design framework to analyze frequency dynamics in such systems. To that end, an averaged model of the DFIG-based wind farm connected to LCC-HVDC system has been developed where grid frequency control is used to regulate the HVDC rectifier firing angle. This paper analyzes the effect of low Effective Short Circuit Ratio (ESCR) and the Effective DC Inertia Constant Hdc on the stability of the system. A systematic design process of the frequency controller parameters reveals a negative interaction between the generator speed-HVDC PLL-frequency controller mode and the DFIG-GSC controller mode.
{"title":"Frequency control for weak AC grid connected to wind farm and LCC-HVDC system: Modeling and stability analysis","authors":"Jagdeep Kaur, Amirthagunaraj Yogarathinam, N. Chaudhuri","doi":"10.1109/PESGM.2016.7741741","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741741","url":null,"abstract":"Interconnection of DFIG-based wind farms with LCC-HVDC is challenging for very weak AC systems. This work focuses on establishing a modeling and control design framework to analyze frequency dynamics in such systems. To that end, an averaged model of the DFIG-based wind farm connected to LCC-HVDC system has been developed where grid frequency control is used to regulate the HVDC rectifier firing angle. This paper analyzes the effect of low Effective Short Circuit Ratio (ESCR) and the Effective DC Inertia Constant Hdc on the stability of the system. A systematic design process of the frequency controller parameters reveals a negative interaction between the generator speed-HVDC PLL-frequency controller mode and the DFIG-GSC controller mode.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116813311","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741229
Young-Jin Kim, L. Norford
This paper presents a closed-loop model in which commercial building aggregators (CBAs) minimize their operating costs in a wholesale electricity market, considering wind power uncertainties that are modeled as contingencies using a set of forecast error scenarios. Specifically, the CBAs determine the optimal energy consumption and reserve deployment of variable speed heat pumps (VSHPs) and plug-in electric vehicles (PEVs) in response to locational marginal prices (LMPs). A two-stage stochastic optimization problem is formulated to model the price-based demand response (DR) of the CBAs. Simulated case studies are performed to estimate variation in the operational costs of the CBAs under various conditions, as determined by the room temperature control methods and the building energy storage resource penetrations.
{"title":"Price-based demand response of energy storage resources in commercial buildings","authors":"Young-Jin Kim, L. Norford","doi":"10.1109/PESGM.2016.7741229","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741229","url":null,"abstract":"This paper presents a closed-loop model in which commercial building aggregators (CBAs) minimize their operating costs in a wholesale electricity market, considering wind power uncertainties that are modeled as contingencies using a set of forecast error scenarios. Specifically, the CBAs determine the optimal energy consumption and reserve deployment of variable speed heat pumps (VSHPs) and plug-in electric vehicles (PEVs) in response to locational marginal prices (LMPs). A two-stage stochastic optimization problem is formulated to model the price-based demand response (DR) of the CBAs. Simulated case studies are performed to estimate variation in the operational costs of the CBAs under various conditions, as determined by the room temperature control methods and the building energy storage resource penetrations.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125838325","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741960
Y. Tohidi, M. Hesamzadeh
This paper proposes a mathematical model for strategic generation expansion planning problem. The model is developed based on the the simultaneous-move game between Gencos. Gencos investment decisions are passed to the dispatch center which decides about the production level in operating scenarios considered. Using Karush-Kuhn-Tucker conditions (KKTs) and disjunctive linearization, the model is formulated as a mixed-integer linear program (MILP). The concepts of worst Nash equilibrium (WNE) and best Nash equilibrium (BNE) are introduced to handle multiple NE problem. The impact of uncertainty (scenarios) on equilibria band, i.e., the difference between WNE and BNE is discussed. The developed model is simulated on illustrative 2-node and 3-node example systems and also on IEEE-RTS96 test system.
{"title":"A mathematical model for strategic generation expansion planning","authors":"Y. Tohidi, M. Hesamzadeh","doi":"10.1109/PESGM.2016.7741960","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741960","url":null,"abstract":"This paper proposes a mathematical model for strategic generation expansion planning problem. The model is developed based on the the simultaneous-move game between Gencos. Gencos investment decisions are passed to the dispatch center which decides about the production level in operating scenarios considered. Using Karush-Kuhn-Tucker conditions (KKTs) and disjunctive linearization, the model is formulated as a mixed-integer linear program (MILP). The concepts of worst Nash equilibrium (WNE) and best Nash equilibrium (BNE) are introduced to handle multiple NE problem. The impact of uncertainty (scenarios) on equilibria band, i.e., the difference between WNE and BNE is discussed. The developed model is simulated on illustrative 2-node and 3-node example systems and also on IEEE-RTS96 test system.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126142087","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741391
T. Williams, K. Kalsi, M. Elizondo, L. Marinovici, R. Pratt
Demand-side frequency control can complement traditional generator controls to maintain the stability of large electric systems in the face of rising uncertainty and variability associated with renewable energy resources. This paper presents a hierarchical frequency-based load control strategy that uses a supervisor to flexibly adjust control gains that a population of end-use loads respond to in a decentralized manner to help meet the NERC BAL-003-1 frequency response standard at both the area level and interconnection level. The load model is calibrated and used to model populations of frequency-responsive water heaters in a PowerWorld simulation of the U.S. Western Interconnection (WECC). The proposed design is implemented and demonstrated on physical water heaters in a laboratory setting. A significant fraction of the required frequency response in the WECC could be supplied by electric water heaters alone at penetration levels of less than 15%, while contributing to NERC requirements at the interconnection and area levels.
{"title":"Control and coordination of frequency responsive residential water heaters","authors":"T. Williams, K. Kalsi, M. Elizondo, L. Marinovici, R. Pratt","doi":"10.1109/PESGM.2016.7741391","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741391","url":null,"abstract":"Demand-side frequency control can complement traditional generator controls to maintain the stability of large electric systems in the face of rising uncertainty and variability associated with renewable energy resources. This paper presents a hierarchical frequency-based load control strategy that uses a supervisor to flexibly adjust control gains that a population of end-use loads respond to in a decentralized manner to help meet the NERC BAL-003-1 frequency response standard at both the area level and interconnection level. The load model is calibrated and used to model populations of frequency-responsive water heaters in a PowerWorld simulation of the U.S. Western Interconnection (WECC). The proposed design is implemented and demonstrated on physical water heaters in a laboratory setting. A significant fraction of the required frequency response in the WECC could be supplied by electric water heaters alone at penetration levels of less than 15%, while contributing to NERC requirements at the interconnection and area levels.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129455930","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 : 2016-07-17DOI: 10.1109/PESGM.2016.7741594
B. Pierre, Ryan T. Elliott, D. Schoenwald, J. Neely, R. Byrne, D. Trudnowski, James Colwell
This paper describes a control scheme to mitigate inter-area oscillations through active damping. The control system uses real-time phasor measurement unit (PMU) feedback to construct a commanded power signal to modulate the flow of real power over the Pacific DC Intertie (PDCI) located in the western North American Power System (wNAPS). A hardware prototype was constructed to implement the control scheme. To ensure safe and reliable performance, the project integrates a supervisory system to ensure the controller is operating as expected at all times. A suite of supervisory functions are implemented across three hardware platforms. If any controller mal-function is detected, the supervisory system promptly disables the controller through a bumpless transfer method. This paper presents a detailed description of the control scheme, simulation results, the bumpless transfer method, and a redundancy and diversity method in the selection of PMU signals for feedback. This paper also describes in detail the supervisory system implemented to ensure safe and reliable damping performance of the real-time wide area damping controller.
{"title":"Supervisory system for a wide area damping controller using PDCI modulation and real-time PMU feedback","authors":"B. Pierre, Ryan T. Elliott, D. Schoenwald, J. Neely, R. Byrne, D. Trudnowski, James Colwell","doi":"10.1109/PESGM.2016.7741594","DOIUrl":"https://doi.org/10.1109/PESGM.2016.7741594","url":null,"abstract":"This paper describes a control scheme to mitigate inter-area oscillations through active damping. The control system uses real-time phasor measurement unit (PMU) feedback to construct a commanded power signal to modulate the flow of real power over the Pacific DC Intertie (PDCI) located in the western North American Power System (wNAPS). A hardware prototype was constructed to implement the control scheme. To ensure safe and reliable performance, the project integrates a supervisory system to ensure the controller is operating as expected at all times. A suite of supervisory functions are implemented across three hardware platforms. If any controller mal-function is detected, the supervisory system promptly disables the controller through a bumpless transfer method. This paper presents a detailed description of the control scheme, simulation results, the bumpless transfer method, and a redundancy and diversity method in the selection of PMU signals for feedback. This paper also describes in detail the supervisory system implemented to ensure safe and reliable damping performance of the real-time wide area damping controller.","PeriodicalId":155315,"journal":{"name":"2016 IEEE Power and Energy Society General Meeting (PESGM)","volume":"43 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129698591","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：