Pub Date : 2017-06-01DOI: 10.1109/EEM.2017.7981956
P. Staudt, Johannes Garttner, Christof Weinhardt
The German electricity market is undergoing the largest transformation since its liberalization. With increasing shares of renewable generation and decreasing spot exchange prices utilities are searching for new business models. Lessons can be learned from the telecommunication industry which has been liberalized at similar times but has been more competitive and customer centric since. In this paper we review the development of both industries along the four dimensions of competition, tariff design, auction design and the quality of service. We then develop an electricity market design based on experiences from the development of the telecommunication industry.
{"title":"Electricity and telecommunication markets: A discussion of market designs","authors":"P. Staudt, Johannes Garttner, Christof Weinhardt","doi":"10.1109/EEM.2017.7981956","DOIUrl":"https://doi.org/10.1109/EEM.2017.7981956","url":null,"abstract":"The German electricity market is undergoing the largest transformation since its liberalization. With increasing shares of renewable generation and decreasing spot exchange prices utilities are searching for new business models. Lessons can be learned from the telecommunication industry which has been liberalized at similar times but has been more competitive and customer centric since. In this paper we review the development of both industries along the four dimensions of competition, tariff design, auction design and the quality of service. We then develop an electricity market design based on experiences from the development of the telecommunication industry.","PeriodicalId":416082,"journal":{"name":"2017 14th International Conference on the European Energy Market (EEM)","volume":"133 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127324864","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 : 2017-06-01DOI: 10.1109/EEM.2017.7981854
Amanda Spisto, S. Vitiello
The push to integrate massive Renewable Energy Sources (RES) puts the future development of power systems under significant uncertainties. This study analyses a private investment in Pumped Hydro Storage (PHS) operating in a zonal market characterized by transmission congestion between zones. This study shows negative NPV values for the investment in PHS technology in two Italian zones. The profit analysis of the private investor should be accompanied by the assessment of its impact on social welfare, represented here in terms of avoided CO2 emissions and RES system integration. PHS operation, despite being costs minimizing from a system standpoint, does not guarantee optimality in terms of social welfare improvement. On the other side, transmission upgrade investment projects are profitable and might contribute to increase the overall social gain. Policy incentives in support to one technology or another would intervene if its social value would at least cover the net loss.
{"title":"Spatial and temporal power shifting from flexible sources. An economic and environmental assessment","authors":"Amanda Spisto, S. Vitiello","doi":"10.1109/EEM.2017.7981854","DOIUrl":"https://doi.org/10.1109/EEM.2017.7981854","url":null,"abstract":"The push to integrate massive Renewable Energy Sources (RES) puts the future development of power systems under significant uncertainties. This study analyses a private investment in Pumped Hydro Storage (PHS) operating in a zonal market characterized by transmission congestion between zones. This study shows negative NPV values for the investment in PHS technology in two Italian zones. The profit analysis of the private investor should be accompanied by the assessment of its impact on social welfare, represented here in terms of avoided CO2 emissions and RES system integration. PHS operation, despite being costs minimizing from a system standpoint, does not guarantee optimality in terms of social welfare improvement. On the other side, transmission upgrade investment projects are profitable and might contribute to increase the overall social gain. Policy incentives in support to one technology or another would intervene if its social value would at least cover the net loss.","PeriodicalId":416082,"journal":{"name":"2017 14th International Conference on the European Energy Market (EEM)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128083354","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 : 2017-06-01DOI: 10.1109/EEM.2017.7981926
Fátima Lima, M. Nunes, J. Cunha
Climate change related emissions have emerged as one of the adverse effects of unsustainable energy use, which poses the challenge of ensuring energy sustainability while accounting for climate change mitigation. In this paper, using the Energy Indicators for Sustainable Development framework, an assessment of GHG emissions trends along with national and international pledges for a set of developed (Portugal and United Kingdom) and developing countries (China and Brazil) is presented, contributing for an insightful comparison of countries that share a common cause, irrespective of their developmental stage. The preliminary results show that UK and China need to focus on the improvement of the renewable nature of their energy mix, whereas Portugal and Brazil need to focus more on measures that contribute to improve the efficient use of energy. Hence, environmental and energy intensity indicators together have allowed to emphasize aspects that would otherwise separately pass unnoticed.
{"title":"Energy indicators framework and climate change policy implications","authors":"Fátima Lima, M. Nunes, J. Cunha","doi":"10.1109/EEM.2017.7981926","DOIUrl":"https://doi.org/10.1109/EEM.2017.7981926","url":null,"abstract":"Climate change related emissions have emerged as one of the adverse effects of unsustainable energy use, which poses the challenge of ensuring energy sustainability while accounting for climate change mitigation. In this paper, using the Energy Indicators for Sustainable Development framework, an assessment of GHG emissions trends along with national and international pledges for a set of developed (Portugal and United Kingdom) and developing countries (China and Brazil) is presented, contributing for an insightful comparison of countries that share a common cause, irrespective of their developmental stage. The preliminary results show that UK and China need to focus on the improvement of the renewable nature of their energy mix, whereas Portugal and Brazil need to focus more on measures that contribute to improve the efficient use of energy. Hence, environmental and energy intensity indicators together have allowed to emphasize aspects that would otherwise separately pass unnoticed.","PeriodicalId":416082,"journal":{"name":"2017 14th International Conference on the European Energy Market (EEM)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128209639","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 : 2017-06-01DOI: 10.1109/EEM.2017.7981988
T. Möbius, F. Müsgens
The electricity system moves step-by-step towards a system built on the use of intermittent renewable energy sources (RES). The implications raise a variety of questions. We provide deeper insights into the impact of uncertain wind power generation on wholesale electricity prices. In particular, we analyse long-term equilibrium prices and their volatility. We develop and apply a stochastic electricity spot market dispatch and investment model with recourse. We perform our calculations on a “green field” and apply a full cost approach. Thus, we investigate market equilibria in the electricity market. We show that the variance of electricity prices remains stable with the introduction of intermittent wind power production, but increases with the appearance of wind curtailment. As we come closer to a real world application, the price variance increases with increasing uncertainty in the market.
{"title":"Electricity market equilibria and intermittent renewables — A stochastic approach","authors":"T. Möbius, F. Müsgens","doi":"10.1109/EEM.2017.7981988","DOIUrl":"https://doi.org/10.1109/EEM.2017.7981988","url":null,"abstract":"The electricity system moves step-by-step towards a system built on the use of intermittent renewable energy sources (RES). The implications raise a variety of questions. We provide deeper insights into the impact of uncertain wind power generation on wholesale electricity prices. In particular, we analyse long-term equilibrium prices and their volatility. We develop and apply a stochastic electricity spot market dispatch and investment model with recourse. We perform our calculations on a “green field” and apply a full cost approach. Thus, we investigate market equilibria in the electricity market. We show that the variance of electricity prices remains stable with the introduction of intermittent wind power production, but increases with the appearance of wind curtailment. As we come closer to a real world application, the price variance increases with increasing uncertainty in the market.","PeriodicalId":416082,"journal":{"name":"2017 14th International Conference on the European Energy Market (EEM)","volume":"600 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132024507","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 : 2017-06-01DOI: 10.1109/EEM.2017.7982015
Beáta Polgári, P. Sőrés, D. Divényi, Á. Sleisz
There are novel technical solutions and complex market roles in the energy market that cannot be associated with one single market participant and thus are difficult to be fitted into the current energy market environment. The article analyzes these assets and roles to help regulators encourage the spread of energy storage assets, enable demand-side flexibility and its appearance on the flexibility market through aggregators.
{"title":"New market roles changing the electricity market model","authors":"Beáta Polgári, P. Sőrés, D. Divényi, Á. Sleisz","doi":"10.1109/EEM.2017.7982015","DOIUrl":"https://doi.org/10.1109/EEM.2017.7982015","url":null,"abstract":"There are novel technical solutions and complex market roles in the energy market that cannot be associated with one single market participant and thus are difficult to be fitted into the current energy market environment. The article analyzes these assets and roles to help regulators encourage the spread of energy storage assets, enable demand-side flexibility and its appearance on the flexibility market through aggregators.","PeriodicalId":416082,"journal":{"name":"2017 14th International Conference on the European Energy Market (EEM)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124020817","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 : 2017-06-01DOI: 10.1109/EEM.2017.7981959
P. Staudt, Franziska Wegner, Johannes Garttner, Christof Weinhardt
As the transition to more renewable energy sources progresses the regional generation clusters of wind and solar generation increase. Since the transmission capacity is limited we can observe an increasing need for redispatch measures in the German electricity grid to accommodate this development. In this paper we analyze the need and costs of redispatch measures and propose a local electricity market setup to create economic incentives for the expansion of generation capacity close to load centers. We introduce an analytical model to investigate small networks and a graph model simulation to deal with more sophisticated structures. We find that redispatch is especially relevant in networks with bottleneck transmission links and rather independent of the overall grid capacity. Furthermore, we argue that transmission capacity needs to be priced explicitly and that graph theory can help in investigating market mechanisms in electricity grids.
{"title":"Analysis of redispatch and transmission capacity pricing on a local electricity market setup","authors":"P. Staudt, Franziska Wegner, Johannes Garttner, Christof Weinhardt","doi":"10.1109/EEM.2017.7981959","DOIUrl":"https://doi.org/10.1109/EEM.2017.7981959","url":null,"abstract":"As the transition to more renewable energy sources progresses the regional generation clusters of wind and solar generation increase. Since the transmission capacity is limited we can observe an increasing need for redispatch measures in the German electricity grid to accommodate this development. In this paper we analyze the need and costs of redispatch measures and propose a local electricity market setup to create economic incentives for the expansion of generation capacity close to load centers. We introduce an analytical model to investigate small networks and a graph model simulation to deal with more sophisticated structures. We find that redispatch is especially relevant in networks with bottleneck transmission links and rather independent of the overall grid capacity. Furthermore, we argue that transmission capacity needs to be priced explicitly and that graph theory can help in investigating market mechanisms in electricity grids.","PeriodicalId":416082,"journal":{"name":"2017 14th International Conference on the European Energy Market (EEM)","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116368826","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 : 2017-06-01DOI: 10.1109/EEM.2017.7981916
M. Henriques, R. Stikkelman
Renewable energy sources are currently presented as an economically viable and environmentally safe option in the near future. A major constraint to the incorporation of wind and solar generation at large scale is the increase of variability in the power system. To assure the perpetual balance between power production and gross consumption a significant improvement on power systems flexibility is required. Such flexibility in the power system can be achieved by two options on the demand side through demand response obtained through industrial processes: Storage and Substitution. The power system model in study contemplates the purchase of electricity from the Dutch Balancing Market. The electricity prices of the Balancing Market are considered unpredictable. The storage system is characterized by the size of the storage tank and by ramp up/down rates, reflecting the changing speed of the production levels. The substitution system is characterized by the ramp rate of substitution between electricity and an alternative energy carrier as input. The impact of the parameters on the Power System Flexibility when connected to the balancing market under several scenarios was analyzed by Linny-R, a software tool that applies Linear Programming optimization. For the storage system a bigger tank size, a higher ramp rate and a high level of predictability will increase the flexibility of the system. As the actual predictability of the balancing market is limited, the flexibility is limited too, which makes the storage system a questionable option. For the substitution system flexibility is increased by a higher ramp. The effect of the predictability is less dominant, which makes substitution a suitable flexibility enabler for the current Dutch market system. In this context, a restructure of the energy markets, considering the prices predictability, is suggested, as a way of easing the penetration of renewable energy sources.
{"title":"Assessing storage and substitution as power flexibility enablers in industrial processes","authors":"M. Henriques, R. Stikkelman","doi":"10.1109/EEM.2017.7981916","DOIUrl":"https://doi.org/10.1109/EEM.2017.7981916","url":null,"abstract":"Renewable energy sources are currently presented as an economically viable and environmentally safe option in the near future. A major constraint to the incorporation of wind and solar generation at large scale is the increase of variability in the power system. To assure the perpetual balance between power production and gross consumption a significant improvement on power systems flexibility is required. Such flexibility in the power system can be achieved by two options on the demand side through demand response obtained through industrial processes: Storage and Substitution. The power system model in study contemplates the purchase of electricity from the Dutch Balancing Market. The electricity prices of the Balancing Market are considered unpredictable. The storage system is characterized by the size of the storage tank and by ramp up/down rates, reflecting the changing speed of the production levels. The substitution system is characterized by the ramp rate of substitution between electricity and an alternative energy carrier as input. The impact of the parameters on the Power System Flexibility when connected to the balancing market under several scenarios was analyzed by Linny-R, a software tool that applies Linear Programming optimization. For the storage system a bigger tank size, a higher ramp rate and a high level of predictability will increase the flexibility of the system. As the actual predictability of the balancing market is limited, the flexibility is limited too, which makes the storage system a questionable option. For the substitution system flexibility is increased by a higher ramp. The effect of the predictability is less dominant, which makes substitution a suitable flexibility enabler for the current Dutch market system. In this context, a restructure of the energy markets, considering the prices predictability, is suggested, as a way of easing the penetration of renewable energy sources.","PeriodicalId":416082,"journal":{"name":"2017 14th International Conference on the European Energy Market (EEM)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114212172","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 : 2017-06-01DOI: 10.1109/EEM.2017.7982010
E. Lakić, T. Medved, J. Zupancic, A. Gubina
Market power and its possible abuse by market participants is one of the main issues in electricity trading and a lot of work is done on establishing trading rules for fair and transparent electricity market. The focus of this paper is to present market power detection techniques which have been proposed in literature with detail review of the tools which could be used in monitoring units of organised electricity market places such as power exchanges. Electricity markets are disposed to collective or collusive market power exercise because of their characteristics and additionally susceptible to the potential exercise of unilateral market power. There have been many insight researches on topic of market power in the deregulated wholesale electricity markets with arising questions how to define, exercise and detect market power. The paper distinguishes between different models for market monitoring and surveillance and the outcomes of the paper can serve as a recommendation and orientation for further tests and researches in the field of the monitoring of market power.
{"title":"The review of market power detection tools in organised electricity markets","authors":"E. Lakić, T. Medved, J. Zupancic, A. Gubina","doi":"10.1109/EEM.2017.7982010","DOIUrl":"https://doi.org/10.1109/EEM.2017.7982010","url":null,"abstract":"Market power and its possible abuse by market participants is one of the main issues in electricity trading and a lot of work is done on establishing trading rules for fair and transparent electricity market. The focus of this paper is to present market power detection techniques which have been proposed in literature with detail review of the tools which could be used in monitoring units of organised electricity market places such as power exchanges. Electricity markets are disposed to collective or collusive market power exercise because of their characteristics and additionally susceptible to the potential exercise of unilateral market power. There have been many insight researches on topic of market power in the deregulated wholesale electricity markets with arising questions how to define, exercise and detect market power. The paper distinguishes between different models for market monitoring and surveillance and the outcomes of the paper can serve as a recommendation and orientation for further tests and researches in the field of the monitoring of market power.","PeriodicalId":416082,"journal":{"name":"2017 14th International Conference on the European Energy Market (EEM)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114755844","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 : 2017-06-01DOI: 10.1109/EEM.2017.7981878
Evgenia Vanadzina
Russia is the second largest gas producer in the world after the US and the main exporter of natural gas to the EU. There were 257 gas-producing companies in Russia at the beginning of 2016, among them the largest producer and exporter of the pipeline gas — Gazprom with production share of 64 %. Currently, Gazprom maintains the status of the pipeline export monopolist. At the same time, it receives the regulated tariffs in the domestic market, as a measure to restrict the market power in the domestic market. The objective of the paper is to examine the impacts of natural gas policy change on the domestic electricity market of Russia. The paper considers different scenarios of the Russian gas market deregulation, and their impact on the electricity prices. A mixed complementarity approach is used to estimate gas prices and its volumes depending on specific policy decision, and final electricity price in different price zones. Russian domestic gas market policy is an important topic, which is often interrelated with export policy, however, receives less attention, and a current paper aims to fulfill this gap.
{"title":"Russian gas market: Domestic market deregulation impact on electricity prices","authors":"Evgenia Vanadzina","doi":"10.1109/EEM.2017.7981878","DOIUrl":"https://doi.org/10.1109/EEM.2017.7981878","url":null,"abstract":"Russia is the second largest gas producer in the world after the US and the main exporter of natural gas to the EU. There were 257 gas-producing companies in Russia at the beginning of 2016, among them the largest producer and exporter of the pipeline gas — Gazprom with production share of 64 %. Currently, Gazprom maintains the status of the pipeline export monopolist. At the same time, it receives the regulated tariffs in the domestic market, as a measure to restrict the market power in the domestic market. The objective of the paper is to examine the impacts of natural gas policy change on the domestic electricity market of Russia. The paper considers different scenarios of the Russian gas market deregulation, and their impact on the electricity prices. A mixed complementarity approach is used to estimate gas prices and its volumes depending on specific policy decision, and final electricity price in different price zones. Russian domestic gas market policy is an important topic, which is often interrelated with export policy, however, receives less attention, and a current paper aims to fulfill this gap.","PeriodicalId":416082,"journal":{"name":"2017 14th International Conference on the European Energy Market (EEM)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114766842","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 : 2017-06-01DOI: 10.1109/EEM.2017.7981984
A. Abani, Nicolas Hary, V. Rious, M. Saguan
This paper proposes a methodology for modeling mothballing decisions in order to better study the different strategies adopted by power plants owners and their impact on power systems (in particular generation adequacy). A system dynamic approach is adopted to build a model which represents investment, mothballing and shutdown decisions in an energy-only market. The results obtained with the proposed modelling methodology highlight the importance of considering mothballing in long term simulation models of power markets. They show how models which neglect mothballing decisions might overestimate or underestimated the level of available capacity, therefore leading to inappropriate policy choices. The proposed methodology could better inform policymakers on their decisions.
{"title":"Considering power plants mothballing in long-term simulation models for liberalized power markets","authors":"A. Abani, Nicolas Hary, V. Rious, M. Saguan","doi":"10.1109/EEM.2017.7981984","DOIUrl":"https://doi.org/10.1109/EEM.2017.7981984","url":null,"abstract":"This paper proposes a methodology for modeling mothballing decisions in order to better study the different strategies adopted by power plants owners and their impact on power systems (in particular generation adequacy). A system dynamic approach is adopted to build a model which represents investment, mothballing and shutdown decisions in an energy-only market. The results obtained with the proposed modelling methodology highlight the importance of considering mothballing in long term simulation models of power markets. They show how models which neglect mothballing decisions might overestimate or underestimated the level of available capacity, therefore leading to inappropriate policy choices. The proposed methodology could better inform policymakers on their decisions.","PeriodicalId":416082,"journal":{"name":"2017 14th International Conference on the European Energy Market (EEM)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114783196","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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