Pub Date : 2002-08-07DOI: 10.1109/PESW.2002.984954
T. Senjyu, H. Yamashiro, K. Uezato, T. Funabashi
This paper presents new approach for thermal unit commitment problem. Unit commitment (UC) problem plays a major role in power systems since the improvement of commitment schedules results in the reduction of operating cost. However, the unit commitment problem is one of the most difficult optimization problems in power system, because they have many constraints. Further, these constraints vary with each unit. To handle these constraints, some cording methods have been proposed. However, these methods require computation time. To overcome these problems, a new genetic operator based on unit characteristic classification and intelligent techniques generating initial populations are introduced. The proposed algorithm was tested on a reported UC problem. From simulation results, satisfactory solutions are obtained in comparison with previously reported results. Numerical results for system of up to 100 units are compared to previously reported results.
{"title":"A unit commitment problem by using genetic algorithm based on unit characteristic classification","authors":"T. Senjyu, H. Yamashiro, K. Uezato, T. Funabashi","doi":"10.1109/PESW.2002.984954","DOIUrl":"https://doi.org/10.1109/PESW.2002.984954","url":null,"abstract":"This paper presents new approach for thermal unit commitment problem. Unit commitment (UC) problem plays a major role in power systems since the improvement of commitment schedules results in the reduction of operating cost. However, the unit commitment problem is one of the most difficult optimization problems in power system, because they have many constraints. Further, these constraints vary with each unit. To handle these constraints, some cording methods have been proposed. However, these methods require computation time. To overcome these problems, a new genetic operator based on unit characteristic classification and intelligent techniques generating initial populations are introduced. The proposed algorithm was tested on a reported UC problem. From simulation results, satisfactory solutions are obtained in comparison with previously reported results. Numerical results for system of up to 100 units are compared to previously reported results.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"113 9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122175130","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 : 2002-08-07DOI: 10.1109/PESW.2002.985086
G. Huang, P. Yan
One way to solve the congestion problem in a deregulated power system is re-dispatching the generation. This paper investigates the impacts of thyristor controlled series capacitor (TCSC) and static VAr compensator (SVC) on this re-dispatch method with the objective of minimizing the total amount of transactions being curtailed. An algorithm of optimal power flow (OPF) to reduce the transaction curtailment through installing TCSC/SVC in the system is proposed in this paper. Both the pool type transaction and the bilateral type transaction can be taken care using this method. This paper also investigates the improvement of total transfer capability (TTC) by using TCSC and SVC with the consideration of transaction patterns. With the increase of TTC, the possibility of congestion occurrence will be reduced. The TTC calculation is solved by OPF. Numerical examples are used to demonstrate the effect of TCSC/SVC on transaction curtailment and TTC improvements. The test results show that the effect is significant. Finally, this paper suggests some potential future research.
{"title":"TCSC and SVC as re-dispatch tools for congestion management and TTC improvement","authors":"G. Huang, P. Yan","doi":"10.1109/PESW.2002.985086","DOIUrl":"https://doi.org/10.1109/PESW.2002.985086","url":null,"abstract":"One way to solve the congestion problem in a deregulated power system is re-dispatching the generation. This paper investigates the impacts of thyristor controlled series capacitor (TCSC) and static VAr compensator (SVC) on this re-dispatch method with the objective of minimizing the total amount of transactions being curtailed. An algorithm of optimal power flow (OPF) to reduce the transaction curtailment through installing TCSC/SVC in the system is proposed in this paper. Both the pool type transaction and the bilateral type transaction can be taken care using this method. This paper also investigates the improvement of total transfer capability (TTC) by using TCSC and SVC with the consideration of transaction patterns. With the increase of TTC, the possibility of congestion occurrence will be reduced. The TTC calculation is solved by OPF. Numerical examples are used to demonstrate the effect of TCSC/SVC on transaction curtailment and TTC improvements. The test results show that the effect is significant. Finally, this paper suggests some potential future research.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126251115","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 : 2002-08-07DOI: 10.1109/PESW.2002.985235
Zheng Xu, Zhi-xin Gao, Changchun Zhou
Several main factors influencing the transmission capability of EHV/UHV AC lines are discussed, including synchronous stability, voltage and reactive power control, series compensation and shunt compensation. A short circuit ratio for AC transmission systems is proposed in this paper, which accurately describes the influence of the two end systems upon the transmission capability. From the above analysis, a set of curves reflecting the relationship between the transmission capability and the transmission distance is developed, which can be used in electric power system planning and design.
{"title":"EHV/UHV AC transmission capability analysis","authors":"Zheng Xu, Zhi-xin Gao, Changchun Zhou","doi":"10.1109/PESW.2002.985235","DOIUrl":"https://doi.org/10.1109/PESW.2002.985235","url":null,"abstract":"Several main factors influencing the transmission capability of EHV/UHV AC lines are discussed, including synchronous stability, voltage and reactive power control, series compensation and shunt compensation. A short circuit ratio for AC transmission systems is proposed in this paper, which accurately describes the influence of the two end systems upon the transmission capability. From the above analysis, a set of curves reflecting the relationship between the transmission capability and the transmission distance is developed, which can be used in electric power system planning and design.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126313644","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 : 2002-08-07DOI: 10.1109/PESW.2002.984958
Gaofeng Xiong, T. Hashiyama, S. Okuma
The daily bidding strategy in a day-ahead electricity auction market is studied from a supplier's point of view. An improved evolution strategy is developed to evolve the bidding strategy and to maximize the supplier's profit in the long run. A perfectly competitive day-ahead electricity auction market, where no supplier possesses the market power and all suppliers winning the market are paid on their own bids, is assumed here. The dynamic and the incomplete information of the market are emphasized. An agent-based simulation method is presented in this paper. The simulation results show the feasibility of the proposed bidding strategy.
{"title":"An evolutionary computation for supplier bidding strategy in electricity auction market","authors":"Gaofeng Xiong, T. Hashiyama, S. Okuma","doi":"10.1109/PESW.2002.984958","DOIUrl":"https://doi.org/10.1109/PESW.2002.984958","url":null,"abstract":"The daily bidding strategy in a day-ahead electricity auction market is studied from a supplier's point of view. An improved evolution strategy is developed to evolve the bidding strategy and to maximize the supplier's profit in the long run. A perfectly competitive day-ahead electricity auction market, where no supplier possesses the market power and all suppliers winning the market are paid on their own bids, is assumed here. The dynamic and the incomplete information of the market are emphasized. An agent-based simulation method is presented in this paper. The simulation results show the feasibility of the proposed bidding strategy.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126500688","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 : 2002-08-07DOI: 10.1109/PESW.2002.984972
M. Kormos, M. Mcelhany, A. Rodriquez
Summary form only given. In order to realize the goal of a nationwide electronic scheduling environment as an integral part of the second phase of OASIS, it has been determined that business practices involved in the conduct of inter-RTO energy transactions will need to be standardized. To provide a basic framework about which to structure a set of uniform business practices, the NERC reliability model is used. The reliability model is a functionally oriented view of the entities that are involved in managing all aspects of interconnected system operation. The NERC model defines the entities involved in all aspects of inter-RTO transactions according to their most basic functions. In addition, it identifies three time intervals with regard to the scheduling process. These are Making Deals or transacting, Scheduling and Approvals, and Real Time. NERC has identified for each time period the responsibilities, interactions and communications between the entities defined in the model. Within this framework, there are identified critical business practices that are necessary to maintain reliability, promote equitable transmission access, and to enhance market and process efficiency. In fashioning the set of business practices presented here, we have consciously set the bar high. In other words, the primary objective is to fashion a set of rules that make the best sense rather than either necessarily trying to accommodate everyone's current practices or taking a "least common denominator" approach. For some, the changes needed to comply will be significant. However, taken in the context of FERC's view of the end state of RTO formation, these changes are perhaps more consistent.
{"title":"OASIS phase II and electronic scheduling-policy decisions, business practices, and implementation","authors":"M. Kormos, M. Mcelhany, A. Rodriquez","doi":"10.1109/PESW.2002.984972","DOIUrl":"https://doi.org/10.1109/PESW.2002.984972","url":null,"abstract":"Summary form only given. In order to realize the goal of a nationwide electronic scheduling environment as an integral part of the second phase of OASIS, it has been determined that business practices involved in the conduct of inter-RTO energy transactions will need to be standardized. To provide a basic framework about which to structure a set of uniform business practices, the NERC reliability model is used. The reliability model is a functionally oriented view of the entities that are involved in managing all aspects of interconnected system operation. The NERC model defines the entities involved in all aspects of inter-RTO transactions according to their most basic functions. In addition, it identifies three time intervals with regard to the scheduling process. These are Making Deals or transacting, Scheduling and Approvals, and Real Time. NERC has identified for each time period the responsibilities, interactions and communications between the entities defined in the model. Within this framework, there are identified critical business practices that are necessary to maintain reliability, promote equitable transmission access, and to enhance market and process efficiency. In fashioning the set of business practices presented here, we have consciously set the bar high. In other words, the primary objective is to fashion a set of rules that make the best sense rather than either necessarily trying to accommodate everyone's current practices or taking a \"least common denominator\" approach. For some, the changes needed to comply will be significant. However, taken in the context of FERC's view of the end state of RTO formation, these changes are perhaps more consistent.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130438534","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 : 2002-08-07DOI: 10.1109/PESW.2002.985234
X. Zhang, D. Manjuré, E. Makram
Deregulation has significantly changed the way present day power systems operate. With economics being the driving force behind the introduction of deregulation, transmission loss minimization has added importance. This paper presents two approaches to determine the optimal bilateral transaction from the point of view of minimizing the total transmission loss. One is based on the load flow and the other uses the loss formula, which does not resort to any online load flow computation. This makes it much superior in terms of computation speed. In spite of the assumptions involved, the loss formula based approach pinpoints the optimal transaction. Results are presented for four test systems.
{"title":"Optimal choice of bilateral contract transaction for minimizing total transmission loss","authors":"X. Zhang, D. Manjuré, E. Makram","doi":"10.1109/PESW.2002.985234","DOIUrl":"https://doi.org/10.1109/PESW.2002.985234","url":null,"abstract":"Deregulation has significantly changed the way present day power systems operate. With economics being the driving force behind the introduction of deregulation, transmission loss minimization has added importance. This paper presents two approaches to determine the optimal bilateral transaction from the point of view of minimizing the total transmission loss. One is based on the load flow and the other uses the loss formula, which does not resort to any online load flow computation. This makes it much superior in terms of computation speed. In spite of the assumptions involved, the loss formula based approach pinpoints the optimal transaction. Results are presented for four test systems.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"1048 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123144867","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 : 2002-08-07DOI: 10.1109/PESW.2002.985243
A. Medina, G. Saucedo, C. M. Sanchez, A. Maldonado, L. Sanchez
This paper describes a method for the experimental determination of saturation and hysteresis characteristics in multilimb power transformers using a direct current source excitation. Among the potential applications of the saturation and hysteresis curves obtained by measurements are diverse electromagnetic transient studies, stability analysis and harmonic and power quality assessment in power systems.
{"title":"Saturation and hysteresis characteristics obtained by measurements in multilimb power transformers using DC excitation","authors":"A. Medina, G. Saucedo, C. M. Sanchez, A. Maldonado, L. Sanchez","doi":"10.1109/PESW.2002.985243","DOIUrl":"https://doi.org/10.1109/PESW.2002.985243","url":null,"abstract":"This paper describes a method for the experimental determination of saturation and hysteresis characteristics in multilimb power transformers using a direct current source excitation. Among the potential applications of the saturation and hysteresis curves obtained by measurements are diverse electromagnetic transient studies, stability analysis and harmonic and power quality assessment in power systems.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120963339","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 : 2002-08-07DOI: 10.1109/PESW.2002.985092
B. Stojković, I. Vujošević
Each EMS (energy management system) relies upon the SCADA system that gathers power system data, processes them and issues control commands. Among the all control functions of an EMS, the AGC (automatic generation control) is the most important one. A SCADA system is characterized by geographical spread, a great amount of data a complexity of belonging equipment, but by a very long period for the finalization and a very high investment costs, too. The long realization period compared with the extremely fast development of the available computer's hardware and software on the world's market, coupled with a permanent need for EMS upgrades caused by privatization of electric utility companies and deregulation of the electricity market, coerce some smaller size electric power companies to think in a different manner. This paper describes that manner - a unique control application, developed and implemented at the real power system. The specific feature of this control system is that it is based on the relatively poor set of power system data (around 70 input data), but a very good overall observability is achieved (around 300 output process informations). The second feature is the hardware a single personal computer with the acquisition interface board in it as the SCADA host, and existing "hybrid" telemetric system for power system data gathering and AGC commands transport. Third - the choice of the Visual Basic language provides a lot of powerful features and unlimited possibilities for future easy-to-make upgrades and improvements, such as: object oriented code, encapsulation of functions, full GUI with animation, various communications including and Web-based one etc.
{"title":"A compact SCADA system for a smaller size electric power system control-a fast, object-oriented and cost-effective approach","authors":"B. Stojković, I. Vujošević","doi":"10.1109/PESW.2002.985092","DOIUrl":"https://doi.org/10.1109/PESW.2002.985092","url":null,"abstract":"Each EMS (energy management system) relies upon the SCADA system that gathers power system data, processes them and issues control commands. Among the all control functions of an EMS, the AGC (automatic generation control) is the most important one. A SCADA system is characterized by geographical spread, a great amount of data a complexity of belonging equipment, but by a very long period for the finalization and a very high investment costs, too. The long realization period compared with the extremely fast development of the available computer's hardware and software on the world's market, coupled with a permanent need for EMS upgrades caused by privatization of electric utility companies and deregulation of the electricity market, coerce some smaller size electric power companies to think in a different manner. This paper describes that manner - a unique control application, developed and implemented at the real power system. The specific feature of this control system is that it is based on the relatively poor set of power system data (around 70 input data), but a very good overall observability is achieved (around 300 output process informations). The second feature is the hardware a single personal computer with the acquisition interface board in it as the SCADA host, and existing \"hybrid\" telemetric system for power system data gathering and AGC commands transport. Third - the choice of the Visual Basic language provides a lot of powerful features and unlimited possibilities for future easy-to-make upgrades and improvements, such as: object oriented code, encapsulation of functions, full GUI with animation, various communications including and Web-based one etc.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"351 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134408930","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 : 2002-08-07DOI: 10.1109/PESW.2002.984988
A. Chuang
This paper presents an analysis of the value of real-time information response. The paper describes how rapid response to market conditions, enabled by access to real-time market information (where real-time is on the order of minutes down to seconds), can impact peak electricity demand. Through rapid response from generation supply during peak demand periods, an effective average increase in generation capacity can be achieved. The average increase is achieved without an increase in annual combustion of fuels used to power generation plants. The benefit of increased effective capacity during peak demand periods without increased fuel consumption is realized through utilization of real-time market information systems, which are generally cheaper and quicker to implement than constructing new power plants.
{"title":"Value of real-time information in competitive generation markets","authors":"A. Chuang","doi":"10.1109/PESW.2002.984988","DOIUrl":"https://doi.org/10.1109/PESW.2002.984988","url":null,"abstract":"This paper presents an analysis of the value of real-time information response. The paper describes how rapid response to market conditions, enabled by access to real-time market information (where real-time is on the order of minutes down to seconds), can impact peak electricity demand. Through rapid response from generation supply during peak demand periods, an effective average increase in generation capacity can be achieved. The average increase is achieved without an increase in annual combustion of fuels used to power generation plants. The benefit of increased effective capacity during peak demand periods without increased fuel consumption is realized through utilization of real-time market information systems, which are generally cheaper and quicker to implement than constructing new power plants.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132936541","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 : 2002-08-07DOI: 10.1109/PESW.2002.985067
M. Ishimaru, R. Yokoyama, G. Shirai, K.Y. Lee
Stabilizing control for power system stability has been applied to generators equipped with an excitation controller and speed governor. Power electronics-based control devices have been the focus of research and development for the improvement of transient stability. Power electronics control devices are utilized for control of the power flow on a transmission line or the reactive power in a power system. In that case, they have no constraint of setting point in a power system. On the other hand, the total number of these devices to be equipped has economical constraints, because their prices are very expensive; therefore, the allocation problem of these controllers is worth studying. This paper proposes an approach to determine the numbers and locations of thyristor-controlled series capacitors (TCSC) in a multi-machine power system. The index of optimal allocation of the controllers is the power system stability. First, the steady-state stability is considered, and then the transient stability is examined to find a robust allocation of the TCSC controllers.
{"title":"Allocation and design of robust TCSC controllers based on power system stability index","authors":"M. Ishimaru, R. Yokoyama, G. Shirai, K.Y. Lee","doi":"10.1109/PESW.2002.985067","DOIUrl":"https://doi.org/10.1109/PESW.2002.985067","url":null,"abstract":"Stabilizing control for power system stability has been applied to generators equipped with an excitation controller and speed governor. Power electronics-based control devices have been the focus of research and development for the improvement of transient stability. Power electronics control devices are utilized for control of the power flow on a transmission line or the reactive power in a power system. In that case, they have no constraint of setting point in a power system. On the other hand, the total number of these devices to be equipped has economical constraints, because their prices are very expensive; therefore, the allocation problem of these controllers is worth studying. This paper proposes an approach to determine the numbers and locations of thyristor-controlled series capacitors (TCSC) in a multi-machine power system. The index of optimal allocation of the controllers is the power system stability. First, the steady-state stability is considered, and then the transient stability is examined to find a robust allocation of the TCSC controllers.","PeriodicalId":198760,"journal":{"name":"2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130975745","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：