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61.
62.
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
63.
Clyve Jones 《Parliamentary History》2013,32(3):522-530
There is much evidence for the parliamentary organisation of the whig junto in Queen Anne's reign, but little for its extra‐parliamentary organisation. This note gives evidence for such extra‐parliamentary organisation late in the reign of William III from letters by both James Vernon and Robert Harley, which describe meetings of the junto and some of its supporters in the country houses of followers in the summers of 1698, 1699 and 1700. 相似文献
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K. Su J.‐P. Latham D. Pavlidis J. Xiang F. Fang P. Mostaghimi J. R. Percival C. C. Pain M. D. Jackson 《Geofluids》2015,15(4):592-607
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
66.
Wei She M. R. Jones Yunsheng Zhang Xing Shi 《International Journal of Architectural Heritage》2015,9(7):775-793
The Hui-style residence is an important architectural heritage of China. The hollow wall structures are widely used to build its exterior wall system. However, the thermal performance of the hollow wall is no longer able to meet the new energy-saving and environmental requirement. This article describes a laboratory study of the development of foamed mortar (FM), with the potential for use in thermal upgrading of the Hui-style hollow wall system without dramatically changing its traditional structure. The key early age, physical, mechanical and thermal properties were systematically measured. Two extended models were respectively developed to calculate compressive strength and thermal conductivity, as a function of porosity. Environment chamber test was also employed to investigate the effectiveness of this novel thermal upgrading approach and the results show that filling the voids with FM can effectively improve the overall thermal resistance of the hollow wall system by 44%, which is almost equal to the overall thermal resistance when using the more expensive commercial inorganic stucco system. In addition, the combination of these two methods yielded an overall thermal resistance of 0.701 m2·K/W, which is even higher than 0.67 m2·K/W for the code required in the hot summer/cold winter climate zone. 相似文献
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Biodiversity and Environmental Change: Monitoring,Challenges and Direction edited by D. LINDENMAYER,E. BURNS,N. THURGATE and A. LOWE (eds), CSIRO Publishing,Melbourne, Australia, 2014, xiv + 624 pp,ISBN: 9780643108561 (hardback), AU$120.00
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CATE MACINNIS‐NG 《Geographical Research》2015,53(2):226-227
69.
Latent trajectory models for space‐time analysis: An application in deciphering spatial panel data
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Li An Ming‐Hsiang Tsou Brian H. Spitzberg Dipak K. Gupta J. Mark Gawron 《Geographical analysis》2016,48(3):314-336
This article introduces latent trajectory models (LTMs), an approach often employed in social sciences to handle longitudinal data, to the arena of GIScience, particularly space‐time analysis. Using the space‐time data collected at county level for the whole United States through webpage search on the keyword “climate change,” we show that LTMs, when combined with eigenvector filtering of spatial dependence in data, are very useful in unveiling temporal trends hidden in such data: the webpage‐data derived popularity measure for climate change has been increasing from December 2011 to March 2013, but the increase rate has been slowing down. In addition, LTMs help reveal potential mechanisms behind observed space‐time trajectories through linking the webpage‐data derived popularity measure about climate change to a set of socio‐demographic covariates. Our analysis shows that controlling for population density, greater drought exposure, higher percent of people who are 16 years old or above, and higher household income are positively predictive of the trajectory slopes. Higher percentages of Republicans and number of hot days in summer are negatively related to the trajectory slopes. Implications of these results are examined, concluding with consideration of the potential utility of LTMs in space‐time analysis and more generally in GIScience. 相似文献
70.
Characterization of a Historical Cannonball from the Fortress of San Juan De Ulúa Exposed to a Marine Environment
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M. Hernandez M. Hernandez‐Escampa C. Abreu J. Uruchurtu M. Bethencourt A. Covelo 《Archaeometry》2016,58(4):610-623
Metallurgical analyses and chemical characterizations were carried out on historical cannonballs from the Fortress of San Juan de Ulúa, Veracruz, México. Cannonballs dating from the 18th and 19th centuries share metallurgical characteristics similar to those of material coming from a shipment of ammunition found in the wreck of a sunken French ship from the battle of Trafalgar. The analyses show that the base material is grey cast iron with a carbon equivalent of 4.94 and a ferritic–perlitic matrix, in which the high phosphorus content has led to the formation of iron phosphide compounds in conjunction with a homogeneous distribution of carbon graphite flakes of Type C. In addition, corrosion products from samples revealed the presence of various crystalline iron compounds (X‐ray diffraction), mostly highly chlorinated iron compounds identified as akaganeite. X‐ray fluorescence identified various characteristics of the corrosion products as a function of the sampling depth. FT–IR spectroscopy revealed that the main difference between the corrosion products (internal and external) is determined by the number of organic species. Differential scanning calorimetry corroborated that these corrosion products are thermally stable compounds at elevated temperatures. 相似文献