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61.
Accessibility instruments can play a valuable role in urban planning practice by providing a practical framework for exploring and testing relationships between land use and transport infrastructure. Despite many available accessibility instruments, they are still not widely used in planning practice. This paper explores the background of this problem by examining the findings of a EU-funded study on the usability and usefulness of existing accessibility instruments. The study applied 16 instruments in local planning contexts according to a standardized process protocol. The outcomes of these so-called experiential workshops were analysed through a standardized measurement protocol, which included participant observation along with pre- and post-workshop practitioner questionnaires. This broad investigation presents a rich analytical tool for understanding how different types of accessibility measures, spatial resolutions of output and levels of comprehensiveness affect usability and usefulness. Based on this we propose 10 technological rules that (a) can be used directly in practice to improve usability of accessibility instruments and (b) can provide hypotheses to be examined in further academic studies. Our results suggest that instead of striving for the ultimate accessibility measure, it would be more effective to identify which measures could successfully serve different user needs in accessibility planning.  相似文献   
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A prominent Western specialist on the Russian economy presents an up-to-date overview of the country's small private business enterprises, here defined as registered enterprises employing up to 200 workers. Navigating through the inadequacies of the statistical evidence, the author presents and analyzes new data on size, employment, branch structure, geographical distribution, and related economic indices covering developments through the end of 1996. The paper highlights a number of factors that repress and impede development of small private enterprises, identifying among the principal obstacles arbitrary government regulation and punitive inspections involving extortion. Remedial measures in taxation and crime prevention as well as other forms of assistance are proposed and discussed. Journal of Economic Literature, Classification Numbers: Ml3, P31, P42. 2 tables, 31 references.  相似文献   
64.
In the course of a zooarchaeological survey of Holocene sites in southern Portugal, a substantial size increase of cattle bones was noted following the Christian reconquista of the 11th–13th centuries AD. A size increase in the course of time within a lineage of domestic livestock is usually considered to represent animal improvement. However several other factors including sex may influence the average size of a sample of mammal bones – cattle exhibit considerable sexual size dimorphism, with bulls being larger than cows. A histogram of the distal widths of a large (n = 44) sample of cattle metacarpals from 15th century Beja (Alentejo, Portugal), revealed a bimodal distribution. It was assumed that the large measurements belonged to males and the small to females. In order to rule out the possibility of a post-Moslem change in the sex ratio of cattle, a sub-sample of 21 cattle metacarpals from Beja was selected and we used genetic markers to identify the sex of the animals to which these metacarpals belonged. The ancient DNA sex of all specimens agreed with the previously assumed sex as determined osteometrically. We conclude that the two nearly separated peaks for the metacarpal distal width measurements do indeed indicate sex. A similar bimodal distribution was obtained from another large but earlier sample of cattle metacarpals from Moslem Alcáçova de Santarém (9th–12th century AD). Although these have not been molecularly sexed and since osteometric sexing has now been validated, we conclude that both small (female) and large (male) peaks are smaller than the 15th century ones and that there was an overall size increase or improvement of cattle in this region. Why the Christians improved cattle is unclear, but a selection for larger beeves for meat is one possibility as is the selection of more robust cattle for power. The spread of the quadrangular or chariot plough in Iberia is known to have occurred at this time. We then use the genetically sexed metacarpals to determine which measurements provide reasonable distinction between the sexes. Both the distal width (BFd; as already noted by Svensson et al., 2008; in Swedish medieval cattle) and the width of the lateral condyle (WCL) offer the best distinction. We also used them as a reference ‘collection’ to sex the medieval and post-medieval cattle metacarpals from Launceston Castle in England. This re-visit of the Launceston data corroborates other evidence indicating increased specialisation (milk and veal) in post-medieval cattle husbandry in England.  相似文献   
65.
Building global knowledge pipelines: The role of temporary clusters   总被引:2,自引:0,他引:2  
Business people and professionals come together regularly at trade fairs, exhibitions, conventions, congresses, and conferences. Here, their latest and most advanced findings, inventions and products are on display to be evaluated by customers and suppliers, as well as by peers and competitors. Participation in events like these helps firms to identify the current market frontier, take stock of relative competitive positions and form future plans. Such events exhibit many of the characteristics ascribed to permanent spatial clusters, albeit in a temporary and intensified form. These short-lived hotspots of intense knowledge exchange, network building and idea generation can thus be seen as temporary clusters. This paper compares temporary clusters with permanent clusters and other types of inter-firm interactions. If regular participation in temporary clusters can satisfy a firm's need to learn through interaction with suppliers, customers, peers and rivals, why is the phenomenon of permanent spatial clustering of similar and related economic activity so pervasive? The answer, it is claimed, lies in the restrictions imposed upon economic activity when knowledge and ideas are transformed into valuable products and services. The paper sheds new light on how interaction among firms in current clusters coincides with knowledge-intensive pipelines between firms in different regions or clusters. In doing so, it offers a novel way of understanding how inter-firm knowledge relationships are organized spatially and temporally.  相似文献   
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Book reviewed in this article:
Gabriel Gorodetsky, Grand Delusion: Stalin and the German Invasion of Russia  相似文献   
68.
We present new data on Early Mesolithic settlements in northern Sweden and discuss the process of pioneer colonization. A new set of radiocarbon dates from archaeological sites push deglaciation of northern Fennoscandia further back in time and demonstrate the rapid arrival of pioneer settlers. Environmental data reveal a highly productive early postglacial setting with plant communities unmatched in present ecosystems. The chronological and technological setting supports immigration from the north and northwest with pioneers relying on a long history of enculturating northern subarctic landscapes.  相似文献   
69.
This text presents the results of a contemporary archaeological investigation of an important Swedish Cold War installation, Command Centre Bjorn. This centre was connected to the Air Force Attack Squadron and together with the coastal artillery and the navy it constituted a crucial part of the Swedish defence efforts during the Cold War period. The text also discusses questions concerning heritage processes, and it stresses that a contemporary archaeology approach can contribute with new insights into the Cold War and its heritage in Sweden, as well as canalize and offer guidance to the huge public interest in the material remains from this period in Sweden.  相似文献   
70.
Hoby on the island of Lolland in the western part of the Baltic Sea is strategically located in a coastal landscape offering abundant resources. In 1920, one of the most richly furnished so‐called “Lübsow type” graves dating to the first century AD was discovered at Hoby. The settlement associated with the grave was recognised in 1999. Excavations of the settlement between 2001 and 2016 have confirmed the central role of Hoby in the Iron Age society. The research has focused on the Iron Age population and the infrastructure on Lolland. The Iron Age open cultural landscape encompassed numerous settlements, richly furnished burials and fortifications, and has produced unique metal finds. The article presents a summary of investigation results.  相似文献   
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