In the context of China’s recent urbanization, the agglomeration and diffusion of the strip-city spatial network are gradually being reconstructed. The ways in which the street network structure affects the underlying logic of economic and social development is worthy of in-depth consideration. This study takes Lanzhou (a typical strip city in China) as a case study, using dynamic, geographic, big data and spatial syntactic-theory models to explore the influence of street network accessibility and structure on the spatial and temporal distribution of strip-city spatial vitality. We use Hotspot Analysis (Getis-Ord Gi*) to analyze the dispersal characteristics of street space vitality. In addition, the spatial and temporal heterogeneity characteristics and mechanism of the influence of street accessibility on spatial vitality are evaluated using the spatial Durbin model (SDM). The results show that: the temporal and spatial performance of urban vitality on weekdays and weekends conforms to people’s daily activities, offering similar spatial agglomeration and dispersion effects; accessibility and pedestrian-friendly streets have better urban spatial vitality clustering; street network integration significantly affects the reshaping of urban vitality, but there is apparent temporal heterogeneity in the degree of impact.

By shortening the transportation time between cities, high-speed rail shortens the spatial distance between cities and exerts a far-reaching influence on urban agglomerations’ spatial structures. In order to explore the influence of high-speed rail on the spatial reconstruction of an urban agglomeration in western China, this paper employs fractal theory to compare and analyze the spatial structure evolution of the Chengdu–Chongqing urban agglomeration in western China before and after the opening of a high-speed railway. The results show that after the completion of the high-speed railway, the intercity accessibility is improved. The Chengdu–Chongqing urban agglomeration’s spatial distribution shows a decreasing density from the central city to the surrounding areas. Furthermore, the urban system presents a trend of an agglomeration distribution. Therefore, strengthening the construction of high-speed rail channels between primary and medium-sized cities, as well as accelerating the construction of intercity railway networks and rapid transportation systems based on high-speed rail cities, would help develop urban agglomerations in western China.

As two kinds of management modes of highway traffic control, lane-control, and speed-control produce different effect under different conditions. In this paper, traffic flow cellular automaton models for four-lane highway system with two opposing directions under the above two modes are established considering car and truck mixed running. Through computer numerical simulating, the fundamental diagrams with different parameters are obtained, and after the analysis of density-flux diagrams, the variation discipline of flux with traffic density under different control models is gained. The results indicate that, compared with lane-control, utilization ratio of road can be further improved with speed-control when the truck number increases. The research result is of great significance for reasonable providing theoretical guidance for highway traffic control.

From the perspective of 19 urban agglomerations and comprehensive transportation between them, this study, selecting node cities as research units, defines both the narrow and generalized corridor accessibility to calculate the corridor accessibility coefficient by the weighted average travel time and investigates their overall pattern. The gravity model improved by comprehensive-time cost is used to calculate the economic subordination degrees between Lanzhou–Xining urban agglomeration and other urban agglomerations. Moreover, the differences in the spatial distribution of inter-provincial logistics connectivity between the individual and total amount in Gansu province are discussed, and then the unbalanced trend of spatial connection is analyzed. The results indicate that the horizontal gradient of accessibility of different regions in China has statistical differences and the time-space compression caused by the layout of main transportation lines in Gansu province presents a typical “corridor effect.” The inter-provincial logistics economic relations in Gansu province demonstrate significant stratification characteristics and an unbalanced “neighbor effect” while there are few provincial groups directly connecting with Gansu province. Finally, based on data analysis and logical deduction, the paper analyzes the current situation, discusses the existing shortcomings and strategic advantages of Gansu province, and tries to give development suggestions in terms of the current opportunities as well as responsibilities.

No abstract