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71.
A lack of clear political commitment together with confusing rules and enforcement often characterize the institutional context of policy implementation and regulatory compliance in developing countries. By connecting such contextual features to existing models of policy implementation and regulatory compliance, we examine how regulatory factors are related to basic and proactive corporate environmental management practices in the Pearl River Delta region in China. Drawing on data derived from both a survey and in‐depth interviews, we show that a perception of clear political commitment to environmental protection across multiple government levels and units is positively associated with business efforts in basic environmental practices, regardless of the specific enforcement intensity. Nevertheless, a perception of clear political commitment is not related to proactive environmental practices. Conversely, a perception of policy ambiguity, in the form of confusing regulatory standards and enforcement, is negatively associated with corporate efforts in both basic and proactive environmental practices; yet, intensive inspections mitigate these negative associations with policy ambiguity.  相似文献   
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Urban commons are characterised in the literature as collectively shared property in the city shaped by a context of scarce resources, population density, and the interaction of strangers. In the broader commons literature, commons appears as a verb, a noun, and a process made by practices of commoning—albeit still with a focus on property. In this paper, I argue that an understanding of urban commons as more‐than‐property is needed to recognise how present but elusive urban commons are. I use examples from interviews and observations conducted at a Women's Library to discuss how the access, use, benefit, care, responsibility, and ownership of this urban commons bring it into being through particular practices of commoning. By questioning current ways of defining urban commons, urban scholars gain a grounded understanding of the role of property, and other practices, in maintaining an urban commons over time.  相似文献   
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Accurate simulation of multiphase flow in fractured porous media remains a challenge. An important problem is the representation of the discontinuous or near discontinuous behaviour of saturation in real geological formations. In the classical continuum approach, a refined mesh is required at the interface between fracture and porous media to capture the steep gradients in saturation and saturation‐dependent transport properties. This dramatically increases the computational load when large numbers of fractures are present in the numerical model. A discontinuous finite element method is reported here to model flow in fractured porous media. The governing multiphase porous media flow equations are solved in the adaptive mesh computational fluid dynamics code IC‐FERST on unstructured meshes. The method is based on a mixed control volume – discontinuous finite element formulation. This is combined with the PN+1DG‐PNDG element pair, which has discontinuous (order N+1) representation for velocity and discontinuous (order N) representation for pressure. A number of test cases are used to evaluate the method's ability to model fracture flow. The first is used to verify the performance of the element pair on structured and unstructured meshes of different resolution. Multiphase flow is then modelled in a range of idealised and simple fracture patterns. Solutions with sharp saturation fronts and computational economy in terms of mesh size are illustrated.  相似文献   
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