As global climate change intensifies and urbanization accelerates, research on urban climate change has become a global concern. Urban decision-makers must determine optimal city sizes to achieve net-zero emissions. However, previous studies have mainly focused on average relationships between city size and carbon emissions, overlooking non-linear dynamics. This study used urban scaling laws to investigate relationships between city size and carbon emissions from population and land perspective across 294 Chinese cities. Results showed a sub-linear relationship between urban population size (UPS) and carbon emissions and a super-linear relationship between urban land size (ULS) and carbon emissions. Regionally, cities in central regions demonstrated higher carbon emission performance than those in western and eastern regions.查看详情>>
Photovoltaic-powered buses offer a promising solution for reducing fossil fuel dependency and alleviating pressure on power grids. This study evaluates the solar energy potential in downtown Beijing by utilizing street view images, meteorological data, and advanced analytical techniques, including deep learning and the radiative transfer model. The analysis incorporates spatial characteristics, seasonal variations, and the impact of weather conditions on solar energy availability. Key findings include: (1) downtown Beijing exhibits substantial solar energy potential, with seasonal and spatial variations. Solar energy levels are highest on east-west oriented streets during summer, reaching up to 15.0 MJ/m2/day, while winter levels can drop to as low as 6.0 MJ/m2/day in densely built areas; (2) photovoltaic-powered buses can generate up to 100 kWh per day, enabling annual travel of 88,500 km under clear skies and 64,300 km under cloudy conditions, while reducing carbon emissions by 88.4 tons and 64.3 tons, respectively; (3) integrating photovoltaic systems into public transportation offers significant economic and environmental benefits, enhancing energy security and promoting sustainability. These results demonstrate the feasibility and advantages of incorporating photovoltaic technology into urban public transit, contributing to the development of sustainable cities by reducing carbon emissions and improving energy efficiency.查看详情>>
条块是我国政府间权责关系配置的制度化安排，在行政运行实践中呈现出复杂的关系形态。既有的经验性研究多聚焦于条块在特定公共政策领域出现的分割或矛盾关系，论证其中特征与机理，本文基于案例研究试图探讨条块共治关系发生的驱动机制。案例选取了中央高度重视、省级垂管加强的生态环境政策领域，描述S省厅与A地级市在“厅市会商”机制作用下条块共同建构产业整改政策议题和方案、共同解决地方生态环境棘手难题的过程，探讨促成条块共识、达成条块共治的调适方式和驱动要素，提出了“块提条统”的条块互动形态。文章在案例基础上，分析了条块经由会商机制，围绕面对共同压力情境、建构共同利益和应对共同风险形成共识性合作机制的缘由及机理。查看详情>>
Performance information (PI) has received significant attention in public administration research. However, evaluating the impact of public sector PI on stakeholders is challenging due to varying empirical results. Drawing on information propagation theory, as well as social and cognitive psychology, we conduct a meta-analysis to examine the effect of public sector PI. Using 461 effect sizes from 75 studies, the meta-analysis reveals PI's positive effects on stakeholder attitudes, behaviors, and perceptions of performance. Moreover, the effects tend to be stronger when PI is sent by third parties, received by citizens, delivered with positive valence, presented in absolute forms, and disseminated in law enforcement administrative subfields and in societies characterized by low power distance. The findings reinforce the significance of public sector PI and illuminate the complex interplay between it and stakeholder responses.查看详情>>
公共政策是公共组织在特定情境中制定的一组相互关联的决策，是含有价值偏好、行动目标、治理工具的制度安排。在很长一段时间，政策往往被视为政治系统的输出结果，学界主要关心“政策如何形成”，聚焦不同利益群体的博弈过程。然而，政策制定不仅发生于当下的政策环境，还受制于过去政策的反作用。20世纪90年代以来，政策科学研究开始将“政策”视为自变量，关注一项政策如何影响未来的政策制定，形成了政策反馈的理论建构。查看详情>>
移动性是城市生活的核心要素。自汽车问世以来，人类对移动性的追求呈现出日益复杂的矛盾态势。一方面，汽车及其配套基础设施显著提升了城市的移动性；另一方面，它们也占据了大量城市空间，导致交通拥堵，并削弱了其他交通方式的通行能力。近年来，以点对点拼车、共享汽车和交通网络公司服务为代表的创新型出行方式应运而生，这些新模式不仅丰富了出行选择，也为缓解汽车主导型交通系统带来的拥堵、空气污染和社会排斥等外部性问题提供了潜在解决方案。然而，它们也可能延续汽车对城市空间的支配地位，难以从根本上改善这些负面外部效应。查看详情>>
