Pub Date : 1995-11-21DOI: 10.1109/EMPD.1995.500748
W. Lachs, D. Sutanto
A method of simulating the post-disturbance dynamics of system voltage instability has been developed in which both the slow and fast phases, reported in incidents, have been replicated by a series of load flows. An analysis of the simulation has shown that changes of voltages and reactive power outputs can not only identify a critical situation but also delineate the affected locality where measures could most usefully be applied. The simulation has unearthed the core problems that must be overcome, the unsustainable increase in transmission line series reactive power losses and the subsequent action of rotor overcurrent protection.
{"title":"The dynamics of system voltage instability","authors":"W. Lachs, D. Sutanto","doi":"10.1109/EMPD.1995.500748","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500748","url":null,"abstract":"A method of simulating the post-disturbance dynamics of system voltage instability has been developed in which both the slow and fast phases, reported in incidents, have been replicated by a series of load flows. An analysis of the simulation has shown that changes of voltages and reactive power outputs can not only identify a critical situation but also delineate the affected locality where measures could most usefully be applied. The simulation has unearthed the core problems that must be overcome, the unsustainable increase in transmission line series reactive power losses and the subsequent action of rotor overcurrent protection.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"211 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116666270","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500786
T.M. Lee, T. Chan
A computer program has been developed to synthesise voltage waveforms with predetermined contents of harmonics up to the twentieth order. Currents of fundamental frequency having various proportions of a single harmonic were then derived using D/A card and an amplifier connecting to a residual-current circuit breaker (RCCB) and load. It was discovered that there was a critical proportion corresponding to each harmonic frequency at which the circuit breaker will be most susceptible to tripping. The harmonics synthesiser was also programmed to generate waveforms representing those resulting from nonlinear circuits and loads. These distorted waveforms were applied to an RCCB to study the changes in its tripping current. Finally, filter circuits were designed for connection across the tripping coil to maintain the consistency of the RCCB tripping characteristics when subjected to distorted current waveforms and voltage spikes.
{"title":"The effects of harmonics on the operational characteristics of residual-current circuit breakers","authors":"T.M. Lee, T. Chan","doi":"10.1109/EMPD.1995.500786","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500786","url":null,"abstract":"A computer program has been developed to synthesise voltage waveforms with predetermined contents of harmonics up to the twentieth order. Currents of fundamental frequency having various proportions of a single harmonic were then derived using D/A card and an amplifier connecting to a residual-current circuit breaker (RCCB) and load. It was discovered that there was a critical proportion corresponding to each harmonic frequency at which the circuit breaker will be most susceptible to tripping. The harmonics synthesiser was also programmed to generate waveforms representing those resulting from nonlinear circuits and loads. These distorted waveforms were applied to an RCCB to study the changes in its tripping current. Finally, filter circuits were designed for connection across the tripping coil to maintain the consistency of the RCCB tripping characteristics when subjected to distorted current waveforms and voltage spikes.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115230496","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500791
Hong-Tzer Yang, Pai-Chuan Yang, C. Huang
This paper proposes an innovative genetic algorithm (GA) approach to solving the thermal unit commitment (UC) problem using a constraint satisfaction technique. Minimum up-time and down-time constraints on the generating units are embedded in the delicately designed binary strings to represent the on-off states of the units. Ramp rate constraints on the units being started up or shut down are tackled in the economic dispatch subprogram by limiting the associated maximum available capacities for generating. Violations of the other constraints are considered by integrating penalty factors into the cost function. The developed algorithm is further paralleled on an 8-processor transputer network, processors of which are arranged in master-slave and dual-direction ring structures, respectively. The proposed approach is tested on the simple 4 thermal units system and the practical Taiwan Power system of 38 thermal units. Speed-up and efficiency for each structure with different number of processors are compared to those of the sequential GA approach. The proposed approach is shown to be well amenable to parallel implementation.
{"title":"Optimization of unit commitment using parallel structures of genetic algorithm","authors":"Hong-Tzer Yang, Pai-Chuan Yang, C. Huang","doi":"10.1109/EMPD.1995.500791","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500791","url":null,"abstract":"This paper proposes an innovative genetic algorithm (GA) approach to solving the thermal unit commitment (UC) problem using a constraint satisfaction technique. Minimum up-time and down-time constraints on the generating units are embedded in the delicately designed binary strings to represent the on-off states of the units. Ramp rate constraints on the units being started up or shut down are tackled in the economic dispatch subprogram by limiting the associated maximum available capacities for generating. Violations of the other constraints are considered by integrating penalty factors into the cost function. The developed algorithm is further paralleled on an 8-processor transputer network, processors of which are arranged in master-slave and dual-direction ring structures, respectively. The proposed approach is tested on the simple 4 thermal units system and the practical Taiwan Power system of 38 thermal units. Speed-up and efficiency for each structure with different number of processors are compared to those of the sequential GA approach. The proposed approach is shown to be well amenable to parallel implementation.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126758169","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500707
A. Akhtar, A. Zin, H. Shaibon, K. L. Lo
This paper presents the results of a study carried out to assess the savings in consumer outage costs that can be accrued as a result of implementing emergency actions strategy. The use of emergency actions strategy plays a significant role in curtailing the consumer outage costs ensuing from unreliable electric service. In order to calculate the savings in outage costs, the probabilistic framework of the frequency and duration method has been used in conjunction with emergency actions. At first, the outage costs of various consumer sectors are estimated without considering the emergency actions. Secondly, the consumer outage costs are calculated by combining the frequency and duration method, and unserved energy with the emergency actions invoked. The results of the savings in consumer outage costs that can be accrued by utilising emergency actions strategy are presented for a synthetic system. The results of the study show that substantial savings in consumer outage costs are obtained by devising and implementing emergency actions strategy in situations of capacity outages. The results are of particular relevance and utility to the underdeveloped and developing countries where capacity shortages occur quite frequently. These results also suggest the importance of emergency actions strategy for electric utilities in reducing the consumer economic losses arising from unreliable electric service.
{"title":"Quantitative evaluation of savings in outage costs by using emergency actions strategy","authors":"A. Akhtar, A. Zin, H. Shaibon, K. L. Lo","doi":"10.1109/EMPD.1995.500707","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500707","url":null,"abstract":"This paper presents the results of a study carried out to assess the savings in consumer outage costs that can be accrued as a result of implementing emergency actions strategy. The use of emergency actions strategy plays a significant role in curtailing the consumer outage costs ensuing from unreliable electric service. In order to calculate the savings in outage costs, the probabilistic framework of the frequency and duration method has been used in conjunction with emergency actions. At first, the outage costs of various consumer sectors are estimated without considering the emergency actions. Secondly, the consumer outage costs are calculated by combining the frequency and duration method, and unserved energy with the emergency actions invoked. The results of the savings in consumer outage costs that can be accrued by utilising emergency actions strategy are presented for a synthetic system. The results of the study show that substantial savings in consumer outage costs are obtained by devising and implementing emergency actions strategy in situations of capacity outages. The results are of particular relevance and utility to the underdeveloped and developing countries where capacity shortages occur quite frequently. These results also suggest the importance of emergency actions strategy for electric utilities in reducing the consumer economic losses arising from unreliable electric service.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127300044","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500736
Hong-Tzer Yang, Tian-Chyi Liang, Kuang-Rong Shih, C. Huang
Applications of grey system modeling techniques to predict power system yearly peak loads and their occurring dates are described in this paper. For yearly peak load forecasting, a new hybrid grey model of GM(1,1) in conjunction with GM(1,2) is proposed. Corresponding dates on which the peak loads occur are predicted by using the topological forecasting method. Complying with the characteristics of minimal historical yearly peak load records (only one peak load value for a year), the grey system techniques used in this paper show that a small amount of historical data (3 to 7 points of data) are required to set up a high forecasting-accuracy model. Effectiveness of the developed models has been demonstrated through predicting the actual Taiwan Power (Taipower) yearly peak loads and the occurring dates.
{"title":"Power system yearly peak load forecasting: a grey system modeling approach","authors":"Hong-Tzer Yang, Tian-Chyi Liang, Kuang-Rong Shih, C. Huang","doi":"10.1109/EMPD.1995.500736","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500736","url":null,"abstract":"Applications of grey system modeling techniques to predict power system yearly peak loads and their occurring dates are described in this paper. For yearly peak load forecasting, a new hybrid grey model of GM(1,1) in conjunction with GM(1,2) is proposed. Corresponding dates on which the peak loads occur are predicted by using the topological forecasting method. Complying with the characteristics of minimal historical yearly peak load records (only one peak load value for a year), the grey system techniques used in this paper show that a small amount of historical data (3 to 7 points of data) are required to set up a high forecasting-accuracy model. Effectiveness of the developed models has been demonstrated through predicting the actual Taiwan Power (Taipower) yearly peak loads and the occurring dates.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125137119","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500718
R. Billinton, M. Pandey, S. Aboreshaid, M. Fotuhi‐Firuzabad
In many of the less industrialized countries throughout the world, reliability is incorporated in power system planning and operation using traditional deterministic techniques. This is the case with the Nepal Power System (NPS), where developed expansion plans have been based on nonprobabilistic criteria. This paper illustrates the application of probabilistic methods to reliability evaluation of the NPS. Evaluations at both the generation and composite generation and transmission system levels have been performed. The overall system and nine major load centers have been assessed. These load points carry in total more than 54% of the system load. An assessment of an expansion plan proposed by the Nepal Electricity Authority (NEA) has been performed. The results indicate the reliability implications associated with the system and the proposed expansion plan, and show that quantitative reliability evaluation of the NPS is both possible and practical.
{"title":"Application of reliability concepts to the Nepal Power System","authors":"R. Billinton, M. Pandey, S. Aboreshaid, M. Fotuhi‐Firuzabad","doi":"10.1109/EMPD.1995.500718","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500718","url":null,"abstract":"In many of the less industrialized countries throughout the world, reliability is incorporated in power system planning and operation using traditional deterministic techniques. This is the case with the Nepal Power System (NPS), where developed expansion plans have been based on nonprobabilistic criteria. This paper illustrates the application of probabilistic methods to reliability evaluation of the NPS. Evaluations at both the generation and composite generation and transmission system levels have been performed. The overall system and nine major load centers have been assessed. These load points carry in total more than 54% of the system load. An assessment of an expansion plan proposed by the Nepal Electricity Authority (NEA) has been performed. The results indicate the reliability implications associated with the system and the proposed expansion plan, and show that quantitative reliability evaluation of the NPS is both possible and practical.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121820252","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500698
P. Verho, P. Jarventausta, M. Karenlampi, J. Partanen
This paper deals with the computerized configuration management of a distribution network. A distribution management system (DMS) has been developed and integrated to other information systems. The DMS provides various functions for configuration management: topology supervision, restoration, maintenance outage planning and reconfiguration. The field crew management and outage cost modeling subfunctions are utilized in the intelligent configuration management functions of the DMS.
{"title":"Intelligent configuration management of distribution network","authors":"P. Verho, P. Jarventausta, M. Karenlampi, J. Partanen","doi":"10.1109/EMPD.1995.500698","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500698","url":null,"abstract":"This paper deals with the computerized configuration management of a distribution network. A distribution management system (DMS) has been developed and integrated to other information systems. The DMS provides various functions for configuration management: topology supervision, restoration, maintenance outage planning and reconfiguration. The field crew management and outage cost modeling subfunctions are utilized in the intelligent configuration management functions of the DMS.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124782914","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500823
M. K. Venkatesha, K. Krishnamurthy
It is well understood that pulse width modulation offers several advantages over other methods when used for the control of power (especially for the control of induction motors). The advantages being that a nearly sinusoidal voltage may be generated and applied to the load. Depending on the switching frequency, higher frequency harmonics are generated which may be filtered out (if desired) with a low rating filter. Single pulse width modulation is obtained by a single pulse bridge inverter with voltage levels of 0, +V, 0, -V volts (also called a 2-point inverter). Multiple pulse width modulation is obtained by a combination of two, single pulse width modulation inverter wave forms suitably shifted with each other using a transformer which results in a waveform of 0, +V, +2V, +V, 0, -V, -2V, -V, 0 volts. Further, in the proposed investigation, a single bridge inverter with a string of switching devices is suggested to be used thereby avoiding the use of transformer for combining the wave forms. Experimental verification is made to verify the satisfactory working of the 3-point inverter in the generation of the pulse width modulation waveform without using a transformer. Due to the absence of the transformer, the circuit suggested for the purpose is light and efficient.
{"title":"A 3-point PWM converter with less low order harmonics","authors":"M. K. Venkatesha, K. Krishnamurthy","doi":"10.1109/EMPD.1995.500823","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500823","url":null,"abstract":"It is well understood that pulse width modulation offers several advantages over other methods when used for the control of power (especially for the control of induction motors). The advantages being that a nearly sinusoidal voltage may be generated and applied to the load. Depending on the switching frequency, higher frequency harmonics are generated which may be filtered out (if desired) with a low rating filter. Single pulse width modulation is obtained by a single pulse bridge inverter with voltage levels of 0, +V, 0, -V volts (also called a 2-point inverter). Multiple pulse width modulation is obtained by a combination of two, single pulse width modulation inverter wave forms suitably shifted with each other using a transformer which results in a waveform of 0, +V, +2V, +V, 0, -V, -2V, -V, 0 volts. Further, in the proposed investigation, a single bridge inverter with a string of switching devices is suggested to be used thereby avoiding the use of transformer for combining the wave forms. Experimental verification is made to verify the satisfactory working of the 3-point inverter in the generation of the pulse width modulation waveform without using a transformer. Due to the absence of the transformer, the circuit suggested for the purpose is light and efficient.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130863171","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500821
W. He, C. Teo
This paper demonstrates a direct approach for fault current calculations without using symmetrical components. By representing a polyphase network in phase-coordinates, i.e. phase voltages, currents and impedances, the unbalanced fault currents can also be analyzed and calculated. The proposed approach is direct and can be implemented easily by solving a set of linear system equations. Identical results for both methods are obtained in a sample network. The following faults are analyzed: phase-to-earth with/without impedance; phase-to-phase fault with/without impedance; two-phase-to-earth fault; and a three-phase fault.
{"title":"Unbalanced short-circuit calculation by phase coordinates","authors":"W. He, C. Teo","doi":"10.1109/EMPD.1995.500821","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500821","url":null,"abstract":"This paper demonstrates a direct approach for fault current calculations without using symmetrical components. By representing a polyphase network in phase-coordinates, i.e. phase voltages, currents and impedances, the unbalanced fault currents can also be analyzed and calculated. The proposed approach is direct and can be implemented easily by solving a set of linear system equations. Identical results for both methods are obtained in a sample network. The following faults are analyzed: phase-to-earth with/without impedance; phase-to-phase fault with/without impedance; two-phase-to-earth fault; and a three-phase fault.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134318614","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 : 1995-11-21DOI: 10.1109/EMPD.1995.500793
W. Lutsch, P. Herberholz
The commercial success of energy utilization depends on the quality of energy management. This quality stems from: staff and managerial qualifications; corresponding use of professional energy management software tools; a forward-looking outlook; and a practical, problem-solving oriented approach to business. To meet the economic and ecological challenges posed by energy management, there is a need for highly sophisticated services in power plant operation, diagnostics, spare part management, inspection and maintenance supported by software for data base applications, simulation and optimization. The aim of this presentation is: (1) to outline the efficiency of computer-aided energy management and optimization; and (2) to discuss new ways of training energy managers using multimedia structures and methods. Interactive, team-oriented learning-by-doing systems (CBT, management business games), together with supporting seminars and management software tools, are major keys to effective plant operations.
{"title":"Power plant services-new methods for cost-effective operation and training","authors":"W. Lutsch, P. Herberholz","doi":"10.1109/EMPD.1995.500793","DOIUrl":"https://doi.org/10.1109/EMPD.1995.500793","url":null,"abstract":"The commercial success of energy utilization depends on the quality of energy management. This quality stems from: staff and managerial qualifications; corresponding use of professional energy management software tools; a forward-looking outlook; and a practical, problem-solving oriented approach to business. To meet the economic and ecological challenges posed by energy management, there is a need for highly sophisticated services in power plant operation, diagnostics, spare part management, inspection and maintenance supported by software for data base applications, simulation and optimization. The aim of this presentation is: (1) to outline the efficiency of computer-aided energy management and optimization; and (2) to discuss new ways of training energy managers using multimedia structures and methods. Interactive, team-oriented learning-by-doing systems (CBT, management business games), together with supporting seminars and management software tools, are major keys to effective plant operations.","PeriodicalId":447674,"journal":{"name":"Proceedings 1995 International Conference on Energy Management and Power Delivery EMPD '95","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130043545","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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