| Exploring the relationship between the transportation and the economy has experienced the evolution process from “correlation” to “capability” to an “energy level” relationship."Energy level" is derived from physics and is widely used in sociology.Energy level has the meaning of energy(capability)and level size.The city energy level,as a hotspot issue of energy level theory,actually refers to the functional energy levels(FEL)of the city,which represents a certain subdivision function or comprehensive function energy levels of a city.Among them,the focus on a certain subdivision of the FEL of a city has become the frontier,such as the research on the tourism energy level and industrial energy level in the academic circle,and how to measure each subdivision function level scientifically is a difficult problem.Transportation energy level(TEL)and economic energy level(EEL)belong to the research scope of a subdivision functional energy level in the city energy level,which are important subdivided functional energy levels in the city energy level,and also need to be focused on research.However,at present,only a certain degree of interpretation and research has been carried out on the EEL,and there is still room for breakthroughs in the measurement of EEL.Moreover,the research on TEL is still in its early stages,and there is a large space to explore.Therefore,it is urgent to explain and study the connotation,mechanism,and measurement of the TEL& EEL in theory.In practice,the phenomenon and problems of the TEL & EEL have increasingly become the focus of government and society.In January 2023,just as the Chongqing Municipal Party Committee,proposed that the Chengdu-Chongqing Economic Circle(CCEC)needs to greatly improve the six energy levels,including the city energy level,infrastructure energy level,industrial energy level,and so on,which contain the problem that the TEL & EEL of CCEC needs to be upgraded urgently.To sum up,given the theoretical and practical needs,this dissertation focuses on the important issues of improving the TEL & EEL of CCEC and conducts systematic research based on the interaction between transportation and economy.The main contents and conclusions of this dissertation are as follows.Firstly,the connotation of the TEL & EEL is defined and explained.The TEL represents the level size of the transportation function in a certain geographic space,which can be expressed by the “mobility” and “accessibility” of the space and its radiation impact on the external area.The EEL represents the economic function level of a certain geographic space,which can be expressed by the “production level”,“living level” and “ecological level” of the space and its radiation impact on the external area.Secondly,this dissertation constructs a measurement model for the TEL & EEL based on the interdependence between “field sources” and “fields”.It constructs a measurement model from the dual perspectives of “internal comprehensive development level” and “external connection level”,breaking through the traditional one-way separation perspective and revealing the essence and laws of transportation and economic energy levels.Thirdly,the measurement of the TEL & EEL of the Chengdu-Chongqing twin city(CCTC)from 2000 to 2019 are measured and the evolution rules are summarized and graded.For the TEL’s measurement model,a multi-dimensional utility combination model which can target at different level characteristics is adopted to calculate the TEL’s measurement values using the “mobility” and “accessibility” of microcirculation,internal circulation,and external circulation measured by various line design capacity specifications and Arcgis10.8 software,etc.For the EEL’s measurement model,the data of each index are collected by the statistical yearbook,and the incomplete model is calibrated and validated from both statistical and empirical angles.Due to inherent vagueness and uncertainty in the independence among the indicators,the EEL’s measurement value is calculated by the comprehensive weight fuzzy integral method.The measurement of the TEL & EEL of CCTC shows that: the TEL & EEL of CCTC is constantly developing,evolving,accumulating,or jumping upward over time.During the 20 years from 2000 to 2019,both Chengdu’s and Chongqing’s TELs experienced three-level transitions with Chongqing’s TEL being constantly ahead of Chengdu’s and maintaining a virtually parallel relation between them with one level difference.The underlying logic behind this is that Chongqing,compared to Chengdu,has the initial endowment of the golden waterway of the Yangtze River.At the same time,Chengdu’s EEL has experienced 3 level transitions,as well as Chongqing’s EEL.Except for the slight difference at the beginning,the EELs of the two cities coincide with each other and are hardly distinguishable.This testifies to the rationality of positioning ChengduChongqing as the two leading cities in Western China.However,their EELs have been lagging behind those of Beijing,which reveals the fact that the CCTC has to improve its EELs.Furthermore,from the viewpoint of sub-indexes,Chengdu outperforms in the“internal comprehensive development level” while Chongqing has the advantage in the“external economic connection level”.This heterogeneity and complementarity of Chengdu and Chongqing present an opportunity to mitigate the stiff competition between the two cities and allow them to jointly improve their EELs.Finally,to avoid the low-level coordination problem and to achieve dynamic prediction,the coupling coordination model and VAR model are used to conduct empirical research on the coupling relationship between the static evolution and dynamic prediction of the measurement values of the TEL& EEL.Research on the coupling relationship between the TEL& EEL of the CCTC shows that:(1)From the perspective of the coupling relationship of static evolution,there are similarities and differences in the overall and sub-system coupling coordination between the TEL& EEL of the CCTC.The commonality is that the 4-pairs coupling coordination of the CCTC is constantly increasing and optimizing,and evolving to a high level;The differences are as follows: In the past 20 years,the coupling coordination of the 4-pairs in Chongqing is always better than that in Chengdu;In the past 20 years,the braking factors of the highlevel evolution of the coupling coordination of the CCTC are different.The driving factor of that of Chengdu is an alternate push-pull type.Among them,2014 is the watershed year,which is TEL-driven in the early stage and the EEL-driven in the later stage,while Chongqing has always been TEL-driven.Chengdu’s hierarchical coupling coordination performance from large to small is microcirculation,internal circulation,and external circulation.In 2019,the microcirculation in Chengdu is in the stage of good coordination,the internal circulation is in the intermediate coordination stage,and the external circulation is only in the mild disorder stage.While the performance from large to small in Chongqing is internal circulation,external circulation,and microcirculation.The internal circulation is the strongest and has reached the level of dual-drive high-quality coordination.The microcirculation is the weakest of the three circulations,indicating that Chongqing’s internal development is extremely unbalanced.It is in line with the reality of Chongqing’s “big city” + “big countryside”.(2)From the perspective of the coupling relationship of the dynamic impulse response prediction,a dual proof is ascertained that there is a long-term equilibrium relationship between TEL& EEL.This result is in line with the reality of the coupling relationship between the two cities.At the same time,it is proved that the TEL is the Granger causality of the EEL,but the EEL is not the Granger causality of the TEL,implying that EEL cannot predict the TEL.The upgrading path of the TEL & EEL of CCEC is as follows: Firstly,the radiation status and characteristics of CCEC are analyzed based on the ESDA model,and it is explained that it needs to be implemented step by step.At present,the upgrading of the TEL & EEL of the CCTC is the key link and breakthrough.Secondly,from the perspective of the CCTC,Chengdu needs double optimization of traffic and economy from the angel of the external circulation;The Chongqing railway network needs to be optimized,and Chengdu’s inter-provincial interactive economy needs to be improved from the internal circulation;The Chongqing highway network needs to be optimized from the microcirculation.Finally,from the overall perspective of CCEC,The Chengdu Economic Circle should take advantage of its economic braking advantages to take advantage of the railway on the southern wing of Sichuan province,which will enter the water transportation spatiotemporal circle,do a good job in rail-water intermodal transport and share the advantages of water transportation in the external circulation of the CCEC.While Chongqing Economic Circle should take advantage of the traffic braking advantages,cultivate the northeast wing of Sichuan province as the economic hinterland,which will undertake the radiation transfer of the manufacturing industry from Chongqing metropolitan circle,and promote the integration of CCEC. |
