A multi-scale unified model of human mobility in urban agglomerations.

Understanding human mobility patterns is vital for the coordinated development of cities in urban agglomerations. Existing mobility models can capture single-scale travel behavior within or between cities, but the unified modeling of multi-scale human mobility in urban agglomerations is still analytically and computationally intractable. In this study, by simulating people's mental representations of physical space, we decompose and model the human travel choice process as a cascaded multi-class classification problem. Our multi-scale unified model, built upon cascaded deep neural networks, can predict human mobility in world-class urban agglomerations with thousands of regions. By incorporating individual memory features and population attractiveness features extracted by a graph generative adversarial network, our model can simultaneously predict multi-scale individual and population mobility patterns within urban agglomerations. Our model serves as an exemplar framework for reproducing universal-scale laws of human mobility across various spatial scales, providing vital decision support for urban settings of urban agglomerations.

Unveiling the Nexus Profile of Embodied Water-Energy-Carbon-Value Flows of the Yellow River Basin in China.

Unveiling the nexus profile of the water-energy-carbon (WEC) and value flows embodied in regional trade is essential for enhancing the co-benefits between economic development and environment conservation. However, minimal research explores the WEC and value-added nexus efficiency of the Yellow Basin River (YRB) with a comprehensive framework. Thus, this study built a nexus framework based on a multiregional input-output model (MRIO) to analyze embodied WEC and value-added flows in the nine provinces of the YRB and all 31 provinces of China, primarily in 2017 compared to 2012 and 2015. Three dimensions (space, sectors, and environmental and economic factors) depict the WEC and value-added nexus patterns. The results from these three dimensions uncovered that the YRB benefits from regional trade but suffers environmental losses, and the development imbalance among the provinces of the basin is exacerbated. The proposed integrated framework can be generalized to water-energy extended nexus analysis in other regions to portray a more complex human-environment system nexus pattern. The new knowledge of how embodied WEC interacts with concomitant economic activities within and beyond the YRB can benefit multiresource-integrated management in the YRB and coordinated regional development in China.