Transport and Mobility Needs for an Ageing Society from a Policy Perspective : Review and Implications

Funding: This research received no external funding.Peer reviewedPublisher PD

Underground Transport : An Overview

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Exploring Differences in Commuting Behaviour among Various Income Groups during Polycentric Urban Development in China : New Evidence and Its Implications

Peer reviewedPublisher PD

Understanding China's metro development : A comparative regional analysis

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A Hierarchical Representation Network for Accurate and Detailed Face Reconstruction from In-The-Wild Images

Limited by the nature of the low-dimensional representational capacity of 3DMM, most of the 3DMM-based face reconstruction (FR) methods fail to recover high-frequency facial details, such as wrinkles, dimples, etc. Some attempt to solve the problem by introducing detail maps or non-linear operations, however, the results are still not vivid. To this end, we in this paper present a novel hierarchical representation network (HRN) to achieve accurate and detailed face reconstruction from a single image. Specifically, we implement the geometry disentanglement and introduce the hierarchical representation to fulfill detailed face modeling. Meanwhile, 3D priors of facial details are incorporated to enhance the accuracy and authenticity of the reconstruction results. We also propose a de-retouching module to achieve better decoupling of the geometry and appearance. It is noteworthy that our framework can be extended to a multi-view fashion by considering detail consistency of different views. Extensive experiments on two single-view and two multi-view FR benchmarks demonstrate that our method outperforms the existing methods in both reconstruction accuracy and visual effects. Finally, we introduce a high-quality 3D face dataset FaceHD-100 to boost the research of high-fidelity face reconstruction. The project homepage is at https://younglbw.github.io/HRN-homepage/.Comment: Accepted by CVPR202

Polychromatic drivers for inertial fusion energy

Although tremendous achievements have been made toward inertial confinement fusion, laser plasma instabilities (LPIs) remain to be an inevitable problem for current drive schemes. To mitigate these instabilities, significant efforts have been paid to produce high-power broadband ultraviolet lasers. However, no practical scheme has been demonstrated up to now for efficient triple-frequency conversion of broadband laser. Here we propose the design of polychromatic drivers for the generation of multicolor beams mainly based upon the optical parametric amplification, which can significantly enhance the third-harmonic conversion efficiency. Each polychromatic light has four colors of monochromatic beamlets with a full spectrum width of 3\%, and the beamlet colors of any two adjacent flanges are different. The suppression effects of such polychromatic lights have been investigated via large scale particle-in-cell simulations, which indicate that more than 35\% of the incident energy can be saved from the LPIs compared with monochromatic lasers for the direct-drive scheme, or high-density filled target for the indirect-drive scheme. The proposed polychromatic drivers are based on the matured technologies, and thus may pave the way towards realization of robust and high-efficiency fusion ignition

Metro systems : Construction, operation and impacts

Peer reviewedPublisher PD

Associations between Children's Physical Activity and Neighborhood Environments Using GIS: A Secondary Analysis from a Systematic Scoping Review.

Regular participation in physical activity is essential for children's physical, mental, and cognitive health. Neighborhood environments may be especially important for children who are more likely to spend time in the environment proximal to home. This article provides an update of evidence for associations between children's physical activity behaviors and objectively assessed environmental characteristics derived using geographical information system (GIS)-based approaches. A systematic scoping review yielded 36 relevant articles of varying study quality. Most studies were conducted in the USA. Findings highlight the need for neighborhoods that are well connected, have higher population densities, and have a variety of destinations in the proximal neighborhood to support children's physical activity behaviors. A shorter distance to school and safe traffic environments were significant factors in supporting children's active travel behaviors. Areas for improvement in the field include the consideration of neighborhood self-selection bias, including more diverse population groups, ground-truthing GIS databases, utilising data-driven approaches to derive environmental indices, and improving the temporal alignment of GIS datasets with behavioral outcomes

Developing Shanghai underground pedestrian system under urbanization: mobility, functionality and equity

Shanghai is being transformed through a process of rapid urbanization. Urbanization has the effects of increasing urban population and the income levels of residents as well as changing the structure of transportation. Under the background, from the 1980s, Shanghai has increasingly built and extended underground pedestrian systems (UPS) within central areas to complement pedestrian networks. UPS have significantly affected urban life in Shanghai under the decades of development but to date, research on UPS usage and perceptions of UPS users has been lacking. This research conducted an on-the-spot survey in Shanghai's UPS in People's Square, Jing'an Temple and Xujiahui areas. Investigation through observation, face to face questionnaires and interviews generated qualitative and quantitative findings on the usage characteristics and perceptions of UPS users. The discussion focused on social usage and equity and the functionality of UPS. It revealed defects in the design and management of Shanghai's UPS, including deficiencies with regard to consideration of the elderly, disabled groups, management of homeless people, the range of merchandise categories and orientation (i.e. way-finding) systems. This research is a significant contribution to enriching knowledge and providing insights into the performance of UPS in a developing country under rapid urbanization