Pub Date : 2018-09-01DOI: 10.1109/TDC-LA.2018.8511785
Angie D. Vasquez, T. Sousa
Wind electric systems can provide several benefits for distribution networks, such as power loss reduction and improvements in voltage level. However, high penetration of this intermittent generation can cause voltage stability problems in the grid. In this way, voltage stability studies are required to analyze the impact of integrating wind generation into the low voltage distribution networks. This paper evaluates the systems steady state based on Cespedes formulation to distribution power flow. This method deletes the voltage phase angle in the equations to solve, obtaining the exact load flow solution using only the voltage magnitudes. Also, the probability calculation method applied to the output power of the Wind Energy Conversion System (WECS) is proposed. This method is based on hourly random simulations to mimic the operation of a generation system, taking into account the fluctuating nature of wind speed. The performance of the algorithm is tested on the modified 30-bus system.
{"title":"Stability Analysis of Distribution Networks using The Cespedes Load Flow Considering Wind Energy Conversion Systems","authors":"Angie D. Vasquez, T. Sousa","doi":"10.1109/TDC-LA.2018.8511785","DOIUrl":"https://doi.org/10.1109/TDC-LA.2018.8511785","url":null,"abstract":"Wind electric systems can provide several benefits for distribution networks, such as power loss reduction and improvements in voltage level. However, high penetration of this intermittent generation can cause voltage stability problems in the grid. In this way, voltage stability studies are required to analyze the impact of integrating wind generation into the low voltage distribution networks. This paper evaluates the systems steady state based on Cespedes formulation to distribution power flow. This method deletes the voltage phase angle in the equations to solve, obtaining the exact load flow solution using only the voltage magnitudes. Also, the probability calculation method applied to the output power of the Wind Energy Conversion System (WECS) is proposed. This method is based on hourly random simulations to mimic the operation of a generation system, taking into account the fluctuating nature of wind speed. The performance of the algorithm is tested on the modified 30-bus system.","PeriodicalId":267301,"journal":{"name":"2018 IEEE PES Transmission & Distribution Conference and Exhibition - Latin America (T&D-LA)","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124214723","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 : 2018-09-01DOI: 10.1109/TDC-LA.2018.8511753
Angélica Felipe da Silva, Wagner Seizo Wokama, D. Bernardon, D. Porto, A. Abaide, R. Milbradt
This paper proposes a methodology for analysis of energy balance of distribution networks using State Estimator and real-time measurements. The tool also can be used to support the identification of non-compliance of meters, error identification between measures obtained from readings and calculated measures by the estimator in each equipment. In addition to providing a better use of the available measurements
{"title":"Methodology for Analysis of Energy Balance using State Estimator and Real-Time Measurementas","authors":"Angélica Felipe da Silva, Wagner Seizo Wokama, D. Bernardon, D. Porto, A. Abaide, R. Milbradt","doi":"10.1109/TDC-LA.2018.8511753","DOIUrl":"https://doi.org/10.1109/TDC-LA.2018.8511753","url":null,"abstract":"This paper proposes a methodology for analysis of energy balance of distribution networks using State Estimator and real-time measurements. The tool also can be used to support the identification of non-compliance of meters, error identification between measures obtained from readings and calculated measures by the estimator in each equipment. In addition to providing a better use of the available measurements","PeriodicalId":267301,"journal":{"name":"2018 IEEE PES Transmission & Distribution Conference and Exhibition - Latin America (T&D-LA)","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116383688","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 : 2018-09-01DOI: 10.1109/TDC-LA.2018.8511720
S. Hincapié, N. Castrillón, J. C. González
In the upcoming years a large amount of unconventional renewable energy is expected in the Colombian power system due to the reduction of the cost of these technologies and the encouragement given by the national government. This situation is a challenge for the Colombian power system operator (XM) which must guarantee a safe, reliable and flexible operation. The integration of these technologies could cause the displacement of the traditional generation such as hydro and thermal. The unconventional renewable energy based generation does not provide inertia to the system such as the conventional generation. In order to determine the necessity of implementing inertia emulation functionality in non-conventional generation to maintain the frequency’s quality, in this paper this feature is added to Type 4 wind based generators. With the aim of modelling this characteristic an additional control loop was added in the WECC model for Type 4 wind turbine controller. This paper shows the aforementioned adaptation of the WECC model and the impact of implementing this feature in the Colombian power system for a scenario with a high penetration of wind generation. The results shows the benefits of this implementation in the frequency response and allow to define the requirements for this controller regarding power systems characteristics.
{"title":"Study of the Implementation of Synthetic Inertia in Wind Turbines and its Impact in the Colombian","authors":"S. Hincapié, N. Castrillón, J. C. González","doi":"10.1109/TDC-LA.2018.8511720","DOIUrl":"https://doi.org/10.1109/TDC-LA.2018.8511720","url":null,"abstract":"In the upcoming years a large amount of unconventional renewable energy is expected in the Colombian power system due to the reduction of the cost of these technologies and the encouragement given by the national government. This situation is a challenge for the Colombian power system operator (XM) which must guarantee a safe, reliable and flexible operation. The integration of these technologies could cause the displacement of the traditional generation such as hydro and thermal. The unconventional renewable energy based generation does not provide inertia to the system such as the conventional generation. In order to determine the necessity of implementing inertia emulation functionality in non-conventional generation to maintain the frequency’s quality, in this paper this feature is added to Type 4 wind based generators. With the aim of modelling this characteristic an additional control loop was added in the WECC model for Type 4 wind turbine controller. This paper shows the aforementioned adaptation of the WECC model and the impact of implementing this feature in the Colombian power system for a scenario with a high penetration of wind generation. The results shows the benefits of this implementation in the frequency response and allow to define the requirements for this controller regarding power systems characteristics.","PeriodicalId":267301,"journal":{"name":"2018 IEEE PES Transmission & Distribution Conference and Exhibition - Latin America (T&D-LA)","volume":"211 12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122978815","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 : 2018-09-01DOI: 10.1109/TDC-LA.2018.8511723
Josimar Tello Maita, A.R.M. Guerra, A. Pavas
This paper presents a formulation of the optimal power flow (OPF) problem for transmission systems with the presence of wind generation. The OPF was modeled as a robust design optimization problem focused on ensuring that the probability that the power balance constraints are observed within a tolerance and that the boundaries of the design variables is respected. A simulation tool was developed implementing the model and it was tested with two power systems, two different wind probability distributions and two solution methods. Test results validated the proposed formulation giving optimal solutions that satisfy the power balance probabilistic constraint with the selected tolerance. The formulation is a simple model to calculate an optimal operation point for a power system with wind farms. This is an initial work in the formulation of an optimal operation model for large scale hybrid power system.
{"title":"Simple Optimal Power Flow Robust Formulation with Wind Generation","authors":"Josimar Tello Maita, A.R.M. Guerra, A. Pavas","doi":"10.1109/TDC-LA.2018.8511723","DOIUrl":"https://doi.org/10.1109/TDC-LA.2018.8511723","url":null,"abstract":"This paper presents a formulation of the optimal power flow (OPF) problem for transmission systems with the presence of wind generation. The OPF was modeled as a robust design optimization problem focused on ensuring that the probability that the power balance constraints are observed within a tolerance and that the boundaries of the design variables is respected. A simulation tool was developed implementing the model and it was tested with two power systems, two different wind probability distributions and two solution methods. Test results validated the proposed formulation giving optimal solutions that satisfy the power balance probabilistic constraint with the selected tolerance. The formulation is a simple model to calculate an optimal operation point for a power system with wind farms. This is an initial work in the formulation of an optimal operation model for large scale hybrid power system.","PeriodicalId":267301,"journal":{"name":"2018 IEEE PES Transmission & Distribution Conference and Exhibition - Latin America (T&D-LA)","volume":"385 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123197637","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 : 2018-09-01DOI: 10.1109/TDC-LA.2018.8511642
J. Mariano Paniagua Contreras, G. Gutiérrez-Alcaraz, V. Hinojosa
This paper proposes the use of Generalized Generation Distribution Factors (GGDF) to model network constraints in the optimal power flow (OPF). In this formulation, the nodal balance equality constraints are modeled using one equality constraint, and the transmission network constraints have been modeled using the GGDF. This formulation is compared vs classical DC formulation. Several popular commercial software are used to evaluate the computational efficiency of the OPF formulations. Both formulations are validated and tested on the PJM 5-bus and IEEE 14-bus systems
{"title":"Comparative Study of Optimal Power Flow Solution using DC and Generalized Generation Distribution Factor Formulations","authors":"J. Mariano Paniagua Contreras, G. Gutiérrez-Alcaraz, V. Hinojosa","doi":"10.1109/TDC-LA.2018.8511642","DOIUrl":"https://doi.org/10.1109/TDC-LA.2018.8511642","url":null,"abstract":"This paper proposes the use of Generalized Generation Distribution Factors (GGDF) to model network constraints in the optimal power flow (OPF). In this formulation, the nodal balance equality constraints are modeled using one equality constraint, and the transmission network constraints have been modeled using the GGDF. This formulation is compared vs classical DC formulation. Several popular commercial software are used to evaluate the computational efficiency of the OPF formulations. Both formulations are validated and tested on the PJM 5-bus and IEEE 14-bus systems","PeriodicalId":267301,"journal":{"name":"2018 IEEE PES Transmission & Distribution Conference and Exhibition - Latin America (T&D-LA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122697045","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 : 2018-09-01DOI: 10.1109/TDC-LA.2018.8511693
Alexi Delgado, P. Motellanos, E. Rosario, L. Zuloaga
Some energy projects became in causes of possible social conflicts during its implantation; in this way and in order to prevent social conflicts, it should conduct a social impact assessment (SIA) before developing an energy project. In this work, we conducted a social impact assessment on a renewable energy project in Lima, Peru, by applying of the grey systems theory. In the case study, four stakeholder groups and five evaluation criteria, for SIA, were identified. Consequently, the results showed that the energy project would have a positive social impact from the point of the view affected population. In addition, the criterion more valuated by population under analysis, was the impact on the research. Moreover, the method applied in this study showed interesting results that could help to authorities from university under study and local authorities to make the best decision about the energy project. In addition, the method could be used to assess social impact from other type of energy projects.
{"title":"Social Impact Assessment on a Renewable Energy Project: A Case Study in Peru","authors":"Alexi Delgado, P. Motellanos, E. Rosario, L. Zuloaga","doi":"10.1109/TDC-LA.2018.8511693","DOIUrl":"https://doi.org/10.1109/TDC-LA.2018.8511693","url":null,"abstract":"Some energy projects became in causes of possible social conflicts during its implantation; in this way and in order to prevent social conflicts, it should conduct a social impact assessment (SIA) before developing an energy project. In this work, we conducted a social impact assessment on a renewable energy project in Lima, Peru, by applying of the grey systems theory. In the case study, four stakeholder groups and five evaluation criteria, for SIA, were identified. Consequently, the results showed that the energy project would have a positive social impact from the point of the view affected population. In addition, the criterion more valuated by population under analysis, was the impact on the research. Moreover, the method applied in this study showed interesting results that could help to authorities from university under study and local authorities to make the best decision about the energy project. In addition, the method could be used to assess social impact from other type of energy projects.","PeriodicalId":267301,"journal":{"name":"2018 IEEE PES Transmission & Distribution Conference and Exhibition - Latin America (T&D-LA)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125111885","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 : 2018-09-01DOI: 10.1109/tdc-la.2018.8511738
An approximated procedure to determine the location of the auxiliary electrodes in the fall-of-potential method, using the method of images for charged metallic spheres is presented. The classical fall-of-potential method is strictly applicable only in the case of grounding systems of small hemispheric electrodes separated by long distances, in homogeneous soil. The proposed method will allow us to consider the influence of the size and location of the current electrode in order to get the correct measuring point of the potential probe, for any distance chosen for the current electrode A grounding system consisting of complex arrangements of conductors, buried in any type of soil can be represented by an equivalent hemisphere, making it possible to obtain the correct measurement point of such system in a simple way, without the use of complex computer programs. The method has been applied to some arrangements of grounding electrodes found in published papers, and compared to them, finding very close agreement in the resultant values of the correct measurement point.
{"title":"An Approximated Procedure to Find the Correct Measurement Point in the Fall-of-Potential Method","authors":"","doi":"10.1109/tdc-la.2018.8511738","DOIUrl":"https://doi.org/10.1109/tdc-la.2018.8511738","url":null,"abstract":"An approximated procedure to determine the location of the auxiliary electrodes in the fall-of-potential method, using the method of images for charged metallic spheres is presented. The classical fall-of-potential method is strictly applicable only in the case of grounding systems of small hemispheric electrodes separated by long distances, in homogeneous soil. The proposed method will allow us to consider the influence of the size and location of the current electrode in order to get the correct measuring point of the potential probe, for any distance chosen for the current electrode A grounding system consisting of complex arrangements of conductors, buried in any type of soil can be represented by an equivalent hemisphere, making it possible to obtain the correct measurement point of such system in a simple way, without the use of complex computer programs. The method has been applied to some arrangements of grounding electrodes found in published papers, and compared to them, finding very close agreement in the resultant values of the correct measurement point.","PeriodicalId":267301,"journal":{"name":"2018 IEEE PES Transmission & Distribution Conference and Exhibition - Latin America (T&D-LA)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125236490","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 : 2018-09-01DOI: 10.1109/TDC-LA.2018.8511734
Victor P. Dardengo, P. A. H. Cavalcante, M. D. de Almeida
The main methods for fault location in HVDC lines are based on traveling waves and their performances are highly dependent on the specified wave speed. Although the wave speed varies according to the fault location, in the conventional single and double-terminal approaches, the wave speed is assumed constant, which directly affects the fault location performance. In this paper, a study about the wavespeed is performed and the accuracy of traveling waves based fault location methods are assessed. Additionally,these approaches are compared to fault location methods that does not require the wave speed specification. The behavior of the wave speed according to the fault location and fault resistance is also discussed. The simulations are performed in PSCAD for a realistic HVDC system.
{"title":"An evaluation of wave speed impacts on fault location methods for HVDC lines","authors":"Victor P. Dardengo, P. A. H. Cavalcante, M. D. de Almeida","doi":"10.1109/TDC-LA.2018.8511734","DOIUrl":"https://doi.org/10.1109/TDC-LA.2018.8511734","url":null,"abstract":"The main methods for fault location in HVDC lines are based on traveling waves and their performances are highly dependent on the specified wave speed. Although the wave speed varies according to the fault location, in the conventional single and double-terminal approaches, the wave speed is assumed constant, which directly affects the fault location performance. In this paper, a study about the wavespeed is performed and the accuracy of traveling waves based fault location methods are assessed. Additionally,these approaches are compared to fault location methods that does not require the wave speed specification. The behavior of the wave speed according to the fault location and fault resistance is also discussed. The simulations are performed in PSCAD for a realistic HVDC system.","PeriodicalId":267301,"journal":{"name":"2018 IEEE PES Transmission & Distribution Conference and Exhibition - Latin America (T&D-LA)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121717933","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 : 2018-09-01DOI: 10.1109/TDC-LA.2018.8511765
Leonardo H. Macedo, M. Ortega-Vazquez, R. Romero
This paper presents a mixed-integer second order cone programming model for the problem of optimal distribution systems expansion planning for improving service restoration. The objective is to obtain a network that allows the load to be restored after the occurrence of a contingency. Expansion of new substations, reinforcement of existing ones, addition and reconductoring of feeders are considered in the formulation of this problem. The objective is to find a meshed network that minimizes expansion costs, as well as the radial topologies for operation in predefined contingency scenarios that minimize the energy not supplied. The model considers the full ac power flow equations for the operation of the system. A24-node network is used to demonstrate the effectiveness of the proposed method. A comparison of the costs of the traditional planning with the costs of planning considering service restoration is carried out.
{"title":"Optimal Distribution Systems Expansion Planning for Improving Service Restoration","authors":"Leonardo H. Macedo, M. Ortega-Vazquez, R. Romero","doi":"10.1109/TDC-LA.2018.8511765","DOIUrl":"https://doi.org/10.1109/TDC-LA.2018.8511765","url":null,"abstract":"This paper presents a mixed-integer second order cone programming model for the problem of optimal distribution systems expansion planning for improving service restoration. The objective is to obtain a network that allows the load to be restored after the occurrence of a contingency. Expansion of new substations, reinforcement of existing ones, addition and reconductoring of feeders are considered in the formulation of this problem. The objective is to find a meshed network that minimizes expansion costs, as well as the radial topologies for operation in predefined contingency scenarios that minimize the energy not supplied. The model considers the full ac power flow equations for the operation of the system. A24-node network is used to demonstrate the effectiveness of the proposed method. A comparison of the costs of the traditional planning with the costs of planning considering service restoration is carried out.","PeriodicalId":267301,"journal":{"name":"2018 IEEE PES Transmission & Distribution Conference and Exhibition - Latin America (T&D-LA)","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114293799","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 : 2018-09-01DOI: 10.1109/TDC-LA.2018.8511694
Sebastián Ramírez-Sandí, J. Quirós-Tortós
Rising temperatures as a result of climate change are likely to increase the adoption of air conditioners (AC), which in turn leads to higher power demands and electric energy consumption. This paper presents a methodology to evaluate the corresponding effects of climate change in distribution networks (DNs). To assess these effects, two climate change scenarios produced by the Intergovernmental Panel on Climate Change, models for residential AC availability, and residential AC demand profiles are used. For the study, a Costa Rican network fully modeled using OpenDSS and load profiles obtained from a power utility are used. Simulation results suggest that even low penetration levels of residential AC units represent a significant part of the DN‘s energy consumption, and that increases the DN demand in hours of high temperatures. This, in turn, highlights that mitigation measures such as demand response programs are necessary to supply the rises in demand.
{"title":"Evaluating the Effects of Climate Change on the Electricity Demand of Distribution Networks","authors":"Sebastián Ramírez-Sandí, J. Quirós-Tortós","doi":"10.1109/TDC-LA.2018.8511694","DOIUrl":"https://doi.org/10.1109/TDC-LA.2018.8511694","url":null,"abstract":"Rising temperatures as a result of climate change are likely to increase the adoption of air conditioners (AC), which in turn leads to higher power demands and electric energy consumption. This paper presents a methodology to evaluate the corresponding effects of climate change in distribution networks (DNs). To assess these effects, two climate change scenarios produced by the Intergovernmental Panel on Climate Change, models for residential AC availability, and residential AC demand profiles are used. For the study, a Costa Rican network fully modeled using OpenDSS and load profiles obtained from a power utility are used. Simulation results suggest that even low penetration levels of residential AC units represent a significant part of the DN‘s energy consumption, and that increases the DN demand in hours of high temperatures. This, in turn, highlights that mitigation measures such as demand response programs are necessary to supply the rises in demand.","PeriodicalId":267301,"journal":{"name":"2018 IEEE PES Transmission & Distribution Conference and Exhibition - Latin America (T&D-LA)","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128067148","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：