This article considers the issues of legal regulation of multimodal transport. Author analyses the problems of multimodal transport in practical activity and opportunity of their development, looks at main points of the multimodal operator’s liability.
{"title":"Legal Regulation of the Multimodal Carriage of Goods","authors":"N. Butakova","doi":"10.2139/ssrn.2284952","DOIUrl":"https://doi.org/10.2139/ssrn.2284952","url":null,"abstract":"This article considers the issues of legal regulation of multimodal transport. Author analyses the problems of multimodal transport in practical activity and opportunity of their development, looks at main points of the multimodal operator’s liability.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126304488","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}
Using national data on vehicles in operation, we examine long-run changes in scrappage patterns in passenger cars and light trucks in the United States between 1969 and 2014. We find that the average lifetime for passenger cars has increased from 12.2 to 15.6 years between 1970s and the 2000s. Our central estimate of the elasticity of scrappage with respect to vehicle prices is -0.4, which is substantially different than values adopted in simulation models. These estimates imply that many policies aimed at reducing gasoline consumption, including Corporate Average Fuel Economy standards and gasoline taxes may produce changes in the used vehicle market that are different than prior studies suggest. We also note that consumer scrappage behavior seems to respond more strongly to changes in vehicle price than changes in gasoline price than standard theory would predict.
{"title":"Vehicle Lifetime Trends and Scrappage Behavior in the U.S. Used Car Market","authors":"A. Bento, Kevin D. Roth, Yiou Zuo","doi":"10.2139/ssrn.2262593","DOIUrl":"https://doi.org/10.2139/ssrn.2262593","url":null,"abstract":"Using national data on vehicles in operation, we examine long-run changes in scrappage patterns in passenger cars and light trucks in the United States between 1969 and 2014. We find that the average lifetime for passenger cars has increased from 12.2 to 15.6 years between 1970s and the 2000s. Our central estimate of the elasticity of scrappage with respect to vehicle prices is -0.4, which is substantially different than values adopted in simulation models. These estimates imply that many policies aimed at reducing gasoline consumption, including Corporate Average Fuel Economy standards and gasoline taxes may produce changes in the used vehicle market that are different than prior studies suggest. We also note that consumer scrappage behavior seems to respond more strongly to changes in vehicle price than changes in gasoline price than standard theory would predict.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133989291","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}
Sustainable transport is the integration of sustainable development in the transport sector. Transportation is the worst performers of the environment. It is true that respond to multiple logical, social, political, economic and technical, which is not conducive to their control. It is in this context that the subject of this article with which it is proposed to study the conditions of sustainable transport in Tunisia. These policies to decouple transport growth and economic development lead to cost savings by reducing environmental costs. This paper focuses on verifying the relationship between transport and economic growth in the first place and transport and environmental effects in second place in the context of a small developing economy, that of Tunisia. Indeed, the period covered is between 1980 and 2008.
{"title":"Literature Review: Conditions of Sustainable Transport","authors":"Rabia Achairi, Ezzeddine Ben Mohamed, A. Bouri","doi":"10.2139/ssrn.2263698","DOIUrl":"https://doi.org/10.2139/ssrn.2263698","url":null,"abstract":"Sustainable transport is the integration of sustainable development in the transport sector. Transportation is the worst performers of the environment. It is true that respond to multiple logical, social, political, economic and technical, which is not conducive to their control. It is in this context that the subject of this article with which it is proposed to study the conditions of sustainable transport in Tunisia. These policies to decouple transport growth and economic development lead to cost savings by reducing environmental costs. This paper focuses on verifying the relationship between transport and economic growth in the first place and transport and environmental effects in second place in the context of a small developing economy, that of Tunisia. Indeed, the period covered is between 1980 and 2008.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122091976","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}
Heavy and uncertain traffic conditions exacerbate the commuting experience of millions of people across the globe. When planning important trips, commuters typically add an extra buffer to the expected trip duration to ensure on-time arrival. Motivated by this, we propose a new traffic assignment model that takes into account the stochastic nature of travel times. Our model extends the traditional model of Wardrop competition when uncertainty is present in the network. The focus is on strategic risk-averse users who capture the trade-off between travel times and their variability in a mean-standard deviation objective, defined as the mean travel time plus a risk-aversion factor times the standard deviation of travel time along a path. We consider both infinitesimal users, leading to a nonatomic game, and atomic users, leading to a discrete finite game. We establish conditions that characterize an equilibrium traffic assignment and find when it exists. The main challenge is posed by the users' risk aversion, since the mean-standard deviation objective is nonconvex and nonseparable, meaning that a path cannot be split as a sum of edge costs. As a result, even an individual user's subproblem---a stochastic shortest path problem---is a nonconvex optimization problem for which no polynomial time algorithms are known. In turn, the mathematical structure of the traffic assignment model with stochastic travel times is fundamentally different from the deterministic counterpart. In particular, an equilibrium characterization requires exponentially many variables, one for each path in the network, since an edge flow has multiple possible path-flow decompositions that are not equivalent. Because of this, characterizing the equilibrium and the socially optimal assignment, which minimizes the total user cost, is more challenging than in the traditional deterministic setting. Nevertheless, we prove that both can be encoded by a representation with just polynomially many paths. Finally, under the assumption that the standard deviations of travel times are independent from edge loads, we show that the worst-case ratio between the social cost of an equilibrium and that of an optimal solution is not higher than the analogous ratio in the deterministic setting. In other words, uncertainty does not further degrade the system performance in addition to strategic user behavior alone.
{"title":"A Mean-Risk Model for the Traffic Assignment Problem with Stochastic Travel Times","authors":"E. Nikolova, N. Stier-Moses","doi":"10.2139/ssrn.2298389","DOIUrl":"https://doi.org/10.2139/ssrn.2298389","url":null,"abstract":"Heavy and uncertain traffic conditions exacerbate the commuting experience of millions of people across the globe. When planning important trips, commuters typically add an extra buffer to the expected trip duration to ensure on-time arrival. Motivated by this, we propose a new traffic assignment model that takes into account the stochastic nature of travel times. Our model extends the traditional model of Wardrop competition when uncertainty is present in the network. The focus is on strategic risk-averse users who capture the trade-off between travel times and their variability in a mean-standard deviation objective, defined as the mean travel time plus a risk-aversion factor times the standard deviation of travel time along a path. We consider both infinitesimal users, leading to a nonatomic game, and atomic users, leading to a discrete finite game. We establish conditions that characterize an equilibrium traffic assignment and find when it exists. The main challenge is posed by the users' risk aversion, since the mean-standard deviation objective is nonconvex and nonseparable, meaning that a path cannot be split as a sum of edge costs. As a result, even an individual user's subproblem---a stochastic shortest path problem---is a nonconvex optimization problem for which no polynomial time algorithms are known. In turn, the mathematical structure of the traffic assignment model with stochastic travel times is fundamentally different from the deterministic counterpart. In particular, an equilibrium characterization requires exponentially many variables, one for each path in the network, since an edge flow has multiple possible path-flow decompositions that are not equivalent. Because of this, characterizing the equilibrium and the socially optimal assignment, which minimizes the total user cost, is more challenging than in the traditional deterministic setting. Nevertheless, we prove that both can be encoded by a representation with just polynomially many paths. Finally, under the assumption that the standard deviations of travel times are independent from edge loads, we show that the worst-case ratio between the social cost of an equilibrium and that of an optimal solution is not higher than the analogous ratio in the deterministic setting. In other words, uncertainty does not further degrade the system performance in addition to strategic user behavior alone.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123767759","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}
Preferences for transport activities are often considered only in terms of time and money. Whilst congestion in automobile traffic increases costs by raising trip durations, the same is less obvious in public transport (PT), especially rail-based. This has lead many economic analyses to conclude that there exists a free lunch by reducing the attractiveness of automobile transport at no (or little) cost for PT users. This article argues that congestion in PT - crowding - is also costly. Using survey data from the Paris metro we estimate the degree to which users value comfort in terms of less crowding. Using a contingent valuation method (CVM) we describe marginal willingness to pay over different parts of the distribution of in-vehicle crowding and consider moderating factors. We conclude that the total welfare cost for a trip rises from e2.42 for a seated passenger to e3.69 under the most congested conditions. We apply our results to the cost-benefit analysis of a recent investment in PT in Paris and consider broader implications for transport policy. In particular, we highlight that PT congestion is a first-order urban externality.
{"title":"Estimating Crowding Costs in Public Transport","authors":"L. Haywood, M. Koning","doi":"10.2139/ssrn.2256332","DOIUrl":"https://doi.org/10.2139/ssrn.2256332","url":null,"abstract":"Preferences for transport activities are often considered only in terms of time and money. Whilst congestion in automobile traffic increases costs by raising trip durations, the same is less obvious in public transport (PT), especially rail-based. This has lead many economic analyses to conclude that there exists a free lunch by reducing the attractiveness of automobile transport at no (or little) cost for PT users. This article argues that congestion in PT - crowding - is also costly. Using survey data from the Paris metro we estimate the degree to which users value comfort in terms of less crowding. Using a contingent valuation method (CVM) we describe marginal willingness to pay over different parts of the distribution of in-vehicle crowding and consider moderating factors. We conclude that the total welfare cost for a trip rises from e2.42 for a seated passenger to e3.69 under the most congested conditions. We apply our results to the cost-benefit analysis of a recent investment in PT in Paris and consider broader implications for transport policy. In particular, we highlight that PT congestion is a first-order urban externality.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124581646","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}
Inspired by the ongoing debate regarding the liberalization of the Spanish railway network, we use real-world information on the features of passenger transportation demand and the existing network infrastructure to build a complex experimental setting. We test the efficiency of alternative service provision obligations imposed to railway companies. Our results show that imposing a minimum service for less profitable connections not only improves consumer and overall welfare but will not harm the companies, because it enhances connectivity and the overall demand on the network. In the absence of such service provision restrictions, the companies failing to recognize the profitability of creating a complete network leave some connections unserved, thus reducing overall demand for passenger services.
{"title":"Service Provision on a Railway Network: A Laboratory Experiment","authors":"Aurora García-Gallego, Nikolaos Georgantzís, Gerardo Sabater","doi":"10.2139/ssrn.2164383","DOIUrl":"https://doi.org/10.2139/ssrn.2164383","url":null,"abstract":"Inspired by the ongoing debate regarding the liberalization of the Spanish railway network, we use real-world information on the features of passenger transportation demand and the existing network infrastructure to build a complex experimental setting. We test the efficiency of alternative service provision obligations imposed to railway companies. Our results show that imposing a minimum service for less profitable connections not only improves consumer and overall welfare but will not harm the companies, because it enhances connectivity and the overall demand on the network. In the absence of such service provision restrictions, the companies failing to recognize the profitability of creating a complete network leave some connections unserved, thus reducing overall demand for passenger services.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"577 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123129652","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}
Driver fatigue is internationally recognized as a significant factor in approximately 15%--20% of commercial road transport crashes. In their efforts to increase road safety and improve working conditions of truck drivers, governments worldwide are enforcing stricter limits on the amount of working and driving time without rest. This paper describes an effective optimization algorithm for minimizing transportation costs for a fleet of vehicles considering business hours of customers and hours of service regulations. The algorithm combines the exploration capacities of population-based metaheuristics, the quick improvement abilities of local search, with forward labeling procedures for checking compliance with complex hours of service regulations. Several speed-up techniques are proposed to achieve an overall efficient approach. The proposed approach is used to assess the impact of different hours of service regulations from a carrier-centric point of view. Extensive computational experiments for various sets of regulations in the United States, Canada, the European Union, and Australia are conducted to provide an international assessment of the impact of different rules on transportation costs and accident risks. Our experiments demonstrate that European Union rules lead to the highest safety, whereas Canadian regulations are the most competitive in terms of economic efficiency. Australian regulations appear to have unnecessarily high risk rates with respect to operating costs. The recent rule change in the United States reduces accident risk rates with a moderate increase in operating costs.
{"title":"Hours of Service Regulations in Road Freight Transport: An Optimization-based International Assessment","authors":"A. Goel, Thibaut Vidal","doi":"10.2139/ssrn.2057556","DOIUrl":"https://doi.org/10.2139/ssrn.2057556","url":null,"abstract":"Driver fatigue is internationally recognized as a significant factor in approximately 15%--20% of commercial road transport crashes. In their efforts to increase road safety and improve working conditions of truck drivers, governments worldwide are enforcing stricter limits on the amount of working and driving time without rest. This paper describes an effective optimization algorithm for minimizing transportation costs for a fleet of vehicles considering business hours of customers and hours of service regulations. The algorithm combines the exploration capacities of population-based metaheuristics, the quick improvement abilities of local search, with forward labeling procedures for checking compliance with complex hours of service regulations. Several speed-up techniques are proposed to achieve an overall efficient approach. The proposed approach is used to assess the impact of different hours of service regulations from a carrier-centric point of view. Extensive computational experiments for various sets of regulations in the United States, Canada, the European Union, and Australia are conducted to provide an international assessment of the impact of different rules on transportation costs and accident risks. Our experiments demonstrate that European Union rules lead to the highest safety, whereas Canadian regulations are the most competitive in terms of economic efficiency. Australian regulations appear to have unnecessarily high risk rates with respect to operating costs. The recent rule change in the United States reduces accident risk rates with a moderate increase in operating costs.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122835187","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}
Like many other cities in developing countries Dhaka is struggling with the problem of how to upgrade and improve existing transit services at a low cost. The ever-increasing chaos and congestion, high rate of accidents and rapidly deteriorating transport operational, management and environmental condition calls for immediate considerations of an alternative transport option that could reduce the transport problem. In the way of searching a fruitful solution to the transport problem, various options are available. The experience of other developing countries (like Columbia, Jakarta) shows that implementation of a bus rapid transit option may come out successful. But, it is still questionable whether the modern space efficient mass transit system particularly introduce of BRT is feasible or not for the present road network system viz. quantity, quality, orientation, functionality as well as land use and transport network structure of this city. This study presents the prevailing transport and traveling scenario and the characteristics of existing mass transit system in Dhaka Metropolitan city. Particular emphasis has been made to assess the feasibility of BRT options as compared to the physical and infrastructural capacity of the road network of Dhaka city. Finally, a set of recommendations have been proposed to improve the physical, infrastructural and operational condition of the transportation system aims at introducing modern mass rapid transit system in Dhaka Metropolitan City to meet the future enormous demand.
{"title":"A Preliminary Feasibility Study of Bus Rapid Transit System in the Context of Present Road Network in Dhaka","authors":"S. M. S. Mahmud, M. Anwar","doi":"10.2139/ssrn.2009988","DOIUrl":"https://doi.org/10.2139/ssrn.2009988","url":null,"abstract":"Like many other cities in developing countries Dhaka is struggling with the problem of how to upgrade and improve existing transit services at a low cost. The ever-increasing chaos and congestion, high rate of accidents and rapidly deteriorating transport operational, management and environmental condition calls for immediate considerations of an alternative transport option that could reduce the transport problem. In the way of searching a fruitful solution to the transport problem, various options are available. The experience of other developing countries (like Columbia, Jakarta) shows that implementation of a bus rapid transit option may come out successful. But, it is still questionable whether the modern space efficient mass transit system particularly introduce of BRT is feasible or not for the present road network system viz. quantity, quality, orientation, functionality as well as land use and transport network structure of this city. This study presents the prevailing transport and traveling scenario and the characteristics of existing mass transit system in Dhaka Metropolitan city. Particular emphasis has been made to assess the feasibility of BRT options as compared to the physical and infrastructural capacity of the road network of Dhaka city. Finally, a set of recommendations have been proposed to improve the physical, infrastructural and operational condition of the transportation system aims at introducing modern mass rapid transit system in Dhaka Metropolitan City to meet the future enormous demand.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133556370","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}
Countries may utilize a long coastline in relation to their landmass as a resource to develop their maritime economy. This paper argues that ASEAN countries differ in utilizing their maritime potential. As a basis for further comparative studies the Center for Policy Research and International Studies (CenPRIS) in Penang developed a set of indicators to measure the maritime potential of nations, the state of their maritime industries and the degree to which the maritime potential has actually been utilized. Using the CenPRIS Ocean Index (COI) shows that Brunei and the Philippines have underutilized their maritime potentials, whereas Singapore and Thailand have made full use of it. Malaysia still has the potential to further develop its maritime economy.
{"title":"Comparing the Maritime Potential of Southeast Asian Nations","authors":"H. Evers, Azhari Karim","doi":"10.2139/ssrn.1941207","DOIUrl":"https://doi.org/10.2139/ssrn.1941207","url":null,"abstract":"Countries may utilize a long coastline in relation to their landmass as a resource to develop their maritime economy. This paper argues that ASEAN countries differ in utilizing their maritime potential. As a basis for further comparative studies the Center for Policy Research and International Studies (CenPRIS) in Penang developed a set of indicators to measure the maritime potential of nations, the state of their maritime industries and the degree to which the maritime potential has actually been utilized. Using the CenPRIS Ocean Index (COI) shows that Brunei and the Philippines have underutilized their maritime potentials, whereas Singapore and Thailand have made full use of it. Malaysia still has the potential to further develop its maritime economy.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130832652","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}
The subject of this paper is a method of evaluating cost and performance of container ships as means of transport in the main part of the intermodal transport chain for ISO containers. The reason for doing so is the continuous development in the size of container ships and the infrastructure development to cater for them, as well as the transport chain development in pre- and on-carriage that cannot be evaluated as riskless. The method described will make clear that the factors for success or lack of success for large container ships can be found almost exclusively in the ports and their hinterland infrastructure.
{"title":"Cost and Performance Evaluation Impacts of Container Vessels on Seaport Container Terminals","authors":"Günther Pawellek, Schönknecht Axel","doi":"10.2139/ssrn.1959372","DOIUrl":"https://doi.org/10.2139/ssrn.1959372","url":null,"abstract":"The subject of this paper is a method of evaluating cost and performance of container ships as means of transport in the main part of the intermodal transport chain for ISO containers. The reason for doing so is the continuous development in the size of container ships and the infrastructure development to cater for them, as well as the transport chain development in pre- and on-carriage that cannot be evaluated as riskless. The method described will make clear that the factors for success or lack of success for large container ships can be found almost exclusively in the ports and their hinterland infrastructure.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134639481","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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