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41.
Aurora Higueras‐Milena Castellano Antonio M. Sáez Romero 《International Journal of Nautical Archaeology》2018,47(1):81-102
The area of La Caleta, north‐west of Cadiz, is a key location for studies of the relationship between the Phoenician city of Gadir and the ocean. The port channel and the small islets that characterize the area was one the busiest sectors of the city, and there are abundant underwater remains attesting to past commercial activities. The area also had an important religious role: two sanctuaries were located at the western end of the rocky promontories that surround the channel, and many items identified as offerings have been found. This article synthesizes previous research and provides an overview of the results of a recent project (2008–2010), which enables a thorough review of the development of the seascape and its use during the 1st millennium BC. 相似文献
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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
44.
Kim L. M. Aluwé Britt M. Starkovich Jeroen Van Vaerenbergh 《Archaeological and Anthropological Sciences》2018,10(2):247-257
The animal remains found at the fourteenth–fifteenth century Hof van Leugenhaeghe are crucial to reconstruct the life of the noble inhabitants, as all buildings were destroyed with the construction of a later estate on the property called the Blauwhof. The diet confirms the high social status of this nobility with the suspected consumption of pig skulls, a possible sign of wealth in late-medieval Flanders. Other signs of a noble diet are found as well: juvenile cattle, a diverse spectrum of game, partridge and grey heron. The observed pattern of a wealthy diet is consistent with the zooarchaeological assemblages found at other noble sites in late-medieval Flanders. 相似文献
45.
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
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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 下载免费PDF全文
CATE MACINNIS‐NG 《Geographical Research》2015,53(2):226-227
48.
Sang-Tae Kim 《European Planning Studies》2015,23(2):238-261
The concept of “clusters” has become central to regional economic development strategies, especially in the high-technology and biotechnology industries. Numerous studies have examined the significance of industrial clusters and their components, but comparatively less attention has been directed towards understanding the roots and processes of industrial localization. In particular, emerging biotechnology clusters such as that in San Diego have not drawn adequate scholarly attention given their policy implications with regard to clustering and regional development. Based on in-depth interviews, historical archives and participatory observations, this paper examines how the San Diego biotechnology cluster emerged and grew into an entrepreneurial habitat that has nurtured hundreds of biotechnology companies that have produced a series of innovative products. The author suggests that the regional context of the existence of a number of small biotechnology companies rather than a group of large firms, a continuous flow of talent, and leadership that fosters collaborations have been critical in promoting knowledge creation, circulation and accumulation, which are essential to spawning startups. The regional advantage of San Diego in stimulating entrepreneurship and innovation lies in its edge in creating and exploiting knowledge and practices through its entrepreneurs' robust interactions and participation in local communities of practice. 相似文献
49.
Latent trajectory models for space‐time analysis: An application in deciphering spatial panel data 下载免费PDF全文
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
50.
Characterization of a Historical Cannonball from the Fortress of San Juan De Ulúa Exposed to a Marine Environment 下载免费PDF全文
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