Transit-oriented development (TOD) has long been recognized as a significant model for prospering urban vibrancy. However, most studies on TOD and urban vibrancy do not consider temporal differences or the nonlinear effects involved. This study applies the gradient boosting decision tree (GBDT) model to metro station areas in Wuhan to explore the nonlinear and synergistic effects of the built-environment features on urban vibrancy during different times. The results show that (1) the effects of the built-environment features on the vibrancy around metro stations differ over time; (2) the most critical features affecting vibrancy are leisure facilities, floor area ratio, commercial facilities, and enterprises; (3) there are approximately linear or complex nonlinear relationships between the built-environment features and the vibrancy; and (4) the synergistic effects suggest that multimodal is more effective at leisure-dominated stations, high-density development is more effective at commercial-dominated stations, and mixed development is more effective at employment-oriented stations. The findings suggest improved planning recommendations for the organization of rail transport to improve the vibrancy of metro station areas.
We apply directly a perturbative expansion to the hopping model of Feinberg. The first three harmonics of the space-charge field are presented, considering the contributions from the higher-order terms at large modulation depth. The dependence of the harmonics on spatial frequency, modulation depth and applied field strength are discussed. An analytical solution of the two-wave coupling equations is given in this case. The mixing gain γ is also discussed.
We discussed the kinetics of the photorefractive fundamental space-charge field with phase-modulation at large modulation depth of the interference pattern. When no external field is applied, the influence of large modulation on the corrected modulation function must be considered at low phase-modulation frequency and at small diffusion field. For the drifted case, the corrected modulation function will increase with increase of the external applied field.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.