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991.
The importance of policy networks has long been emphasized within the field of policy analysis. However, few attempts have been made to investigate the explanatory power of policy networks using the tools and theoretical concepts provided by social network analysis (SNA). This paper aims to address this need by determining if a relationship exists between the structural features of policy networks, their organizing capacities, and their performance. A comparative case study of four networks within the higher education policy sector confirms the assumption related to the existence of such a relation. It is proposed that an efficient and innovative policy network consists of a heterogeneous set of actors that are centrally and densely integrated. Furthermore, while the level of network heterogeneity is positively related to the function of resource mobilization in the process of policymaking, the level of centralized integration promotes the function of prioritizing. These findings are believed to contribute to our understanding of policymaking in contemporary society. The current paper indicates that a significant explanatory power exists in the concept of policy networks and that SNA is one way of advancing its possibilities.  相似文献   
992.
Satala is one of the last great military centers in the Roman East available for archaeological and historical investigations. This archaeological site is situated on the crossing of two singularly important routes in North-East Asia Minor. Only little archaeological fieldwork in and around Satala has so far been carried out, thus delimiting our knowledge of the site and its role within the Roman military structure of the East. In order to provide further data on the site, we carried out geophysical surveys including the application of magnetic and electrical resistivity techniques in an area north of the Sadak village. The geophysical surveys within this area (supposedly part of the Roman military camp) proceeded in two stages. The first stage saw magnetic gradiometer imaging studies being carried out on 2.1 ha, measured by a Geoscan FM-36 fluxgate gradiometer by using 0.5 × 1 m grid intervals. For the second stage a different geophysical technique was used—resistivity tomography. Resistivity data were collected using a number of combined 2D resistivity pseudosections in the eastern part of the area which contained very regular magnetic anomalies. The 3D data were obtained by the combination of all survey lines collected from 2D data sets, and thereafter the arranged data were processed by using the 3D robust inversion modified from the smoothness-constrained algorithm. Electrical resistivity tomography investigations revealed that the buried archaeological structures might be located near the surface, except for some structures found in the middle of the studied area. The archaeological structures were furthermore determined by realistic model sections and volumetric representations. Magnetic imaging and electrical resistivity tomography surveys show that the combined usage of these techniques advances the understanding of archaeological structures beneath the surface.  相似文献   
993.
Human translocation by stowaway transport is the widely accepted vector of the current worldwide distribution of commensal rodents but its historical process has never been directly evidenced. The anecdotal find of the small murine (mice and rats) mandible among the wealthy cargo of the Uluburun shipwreck provide us with an unexpected opportunity to directly evidence the species associated with this stowaway and provide indirect clues regarding the ship's route. Taxonomic identification and geographic sourcing has been performed using outline molar shape analysis by Elliptic Fourier Transform comparing the Uluburun mouse molar phenotype with extant populations from eastern Mediterranean sibling species. Results showed that the mandible belonged to the house mouse (Mus musculus domesticus) with significant phenotypic similarities with extant Syrian house mouse populations. These results provide the earliest direct evidence for stowaway transports highlighting the historical process of the house mouse invasion of the Mediterranean. Using modern behavioural comparisons, combined with archaeological and historical sources, it has been argued that the servicing port of Ugarit (Minet el Beida) was a likely step on the vessel's last journey.  相似文献   
994.
The upland of Dartmoor, southwest England, is one of the flagship prehistoric landscapes within Britain owing to the excellent survival of extensive prehistoric coaxial field systems. Archaeological surveys and rescue excavations during the 1970s and 1980s did much to further the understanding of this landscape; however, much remains to be explored, in particular the chronology of enclosure, the nature of the pre-enclosure landscape and the relationship between Bronze Age communities and their environment. Reconsideration of this landscape is important, given the place it holds in our understanding of subdivision of the landscape across northwest Europe during prehistory. This paper presents new palaeoecological data recovered as part of an integrated archaeological and palaeoecological project on northeast Dartmoor. The sequences detailed here include the first dated Neolithic period palaeoenvironmental data from within the prehistoric enclosed land on the moor, providing a longer-term context for enclosure. Neolithic groups are implicated in the first establishment of heathland in the study area at around 3630–3370 cal BC. During the early Bronze Age, reestablishment of hazel scrub in the study area implies reduced use of the upland, although it is not clear whether this is local or indicative of the wider landscape. A combination of pollen and fungal spore data indicates a substantial shift to species-rich grassland with grazing animals at c.1480 cal BC in a phase that lasted 400 years. The later Bronze Age and early Iron Age are characterised by low intensity use of the upland. These data provide new chronological data for land cover change on Dartmoor and whilst they broadly confirm existing models of upland land use in later prehistory, their proximity to the standing archaeology affords a more nuanced interpretation of local change.  相似文献   
995.
In combination, the analysis of carbonized food residue for stable C and N isotopes, elemental composition, and plant microfossils (phytoliths and starch granules) offers a powerful tool for understanding patterns of prehistoric maize (Zea mays) consumption in small-scale societies. Using this approach, we conclude that maize was more widely consumed in North America than previously suspected. Between ∼AD 700 and 1600, despite little or no archaeological evidence of gardening, corn was a widespread component of diet on the eastern Canadian prairies. This pattern, furthermore, extended into the adjacent boreal forest at about the same time. However, carbon (δ13C) and nitrogen (δ15N) values on food residue samples vary widely, suggesting significant overall dietary differences from one region to the next. Analysis of a subset of residue samples for elemental composition (using ICP-OES [inductively coupled plasma–optical emission spectrometry]) may help identify broad trends in the provenience of foods consumed at these sites.  相似文献   
996.
997.
998.
This paper deals with the question of agglomeration of economic of activities and the internet industry in Stockholm, Sweden. The paper discusses the importance of proximity, especially in the knowledge transmission, and uses a theoretical framework of localized and tacit knowledge. The empirical findings suggests that firms within the internet industry are located in close proximity to each other because of the importance of dense informal interpersonal networks, that facilitate the search for new customers and collaborators. The findings also stress the importance of proximity in creating these dense networks and being in the right place at the right time.  相似文献   
999.
Previous studies on geographical distribution of economic activity in Turkey demonstrate that firms are localized in major metropolitan areas as well as a set of emerging regions. The aim of the paper is to complement the findings of the studies on regional and industrial concentration in Turkey's manufacturing industry by exploring whether regional specialization and industrial concentration patterns changed during the 1980–2000 period. The paper further aims to explore the driving forces of industrial concentration in Turkey's manufacturing industry, particularly during Turkey's economic integration process that started with trade liberalization after 1980 and further developed with the Customs Union in 1996. Regional specialization and industrial concentration are measured by GINI indices Turkey's NUTS-2 regions at the four-digit level for the years between 1980 and 2000. To investigate which variables determine industry concentration, systematic relation between the characteristics of the industry and industrial concentration is tested. Following the method proposed by Paluzie, Pons and Tirado, a panel regression equation is estimated, where the dependent variable is the Gini concentration index and the independent variables are the variables that represent the characteristics of the sectors that follow the predictions of classical trade theory, new trade theory and new economic geography. The major finding of the study is that during 1980–2000, Turkey's regions became more specialized and industry became more concentrated. Increases in the average values of regional specialization and industrial concentration support the prediction developed by Krugman hypothesis that regions become more specialized and industries become more concentrated with economic integration. In exploring the driving forces of industrial concentration, the findings demonstrate that firms tend to cluster in regions where there are economies of scale.  相似文献   
1000.
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