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Identifying urban employment centers (UECs) is crucial for understanding urban spatial structures. Conventional identification methods use census-type aggregated data. The increasing pervasiveness of mobile phone data provides new possibilities to analyze UECs at finer spatial resolution but requires novel identification methods. This study proposes a new approach, the Locally Decaying Model (LDM), to fit the employment density locally and identify UECs based on statistically significant local peaks. We compared the proposed LDM with conventional methods by Monte-Carlo simulation and real data experiments on employment distributions generated from Shanghai mobile phone data. The Monte-Carlo simulation showed that the LDM performed significantly better. The Shanghai case study demonstrated greater stability of the LDM in identifying UEC numbers and locations on aggregated data than the conventional methods. Furthermore, UECs extracted by LDM from the employment density raster were more consistent with the existing local plan. This research contributed a new subcenter identification method that can be applied to recently available urban big data and a comprehensive analytical framework for evaluating such methods. [ABSTRACT FROM AUTHOR]

Opening gated communities (GCs) has been widely discussed for urban inclusion and revitalization. With the policies of opening GCs being promoted in China, the quantitative and comprehensive evaluation of the potential benefits is heavily needed. Taking Shanghai as an example, this study quantifies and analyzes the accessibility benefits and risks of opening GCs for pedestrians and cyclists considering two GC types, two opening levels, two travel modes, and different facilities. We found that (1) opening GCs can bring 50 m+ accessibility gains to 17% and 52% of the residents in moderate opening (MO) and complete opening (CO) scenarios, respectively. (2) Cyclists benefits more than pedestrians in all scenarios. (3) Conventional GCs have fewer benefits in MO but more in CO than newly established ones. Trips to bus stations demonstrate the largest accessibility gains. (4) The accessibility benefit of a residential building is highly determined by its closeness to the gates and relative location in the block. (5) Only 1% and 5–7% of external trips may penetrate the opened communities in MO and CO scenarios, respectively, which are far less than both the expectation and the benefits. Finally, several local design guidelines are proposed. [ABSTRACT FROM AUTHOR]