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131.
Inventing is an important prerequisite for industrial economies to remain technologically competitive. Yet it is not well known how inventive companies of domestic or foreign ownership can affect a nation's technological base and, ultimately, its spatial-economic system. The present study examines this relationship in Canada by investigating the performance of its indigenous and foreign-owned inventive companies at the national, subnational, and urban levels. The results indicate that: (1) Canada's indigenous inventive companies are distinct from their foreign-owned counterparts in that they are generally smaller, are more apt to have teams of inventors, are more likely to develop product inventions, have come to manage a greater share of this nation's inventions, and are increasing their role in key Canadian industries; and (2) geographically, Canada's two largest cities and its core region were adversely affected by the declining inventiveness of American-controlled companies during the 1980s. L'esprit ?invention est une nécessité pour que les économies industrielles restent en conditions de concurrence technologique. Cependant, on connaît très peu de la manière que les entreprises inventives de propriété domestique ou étrangère affectent la base technologique ?un pays et, enfin, affectent son système spatio-écono-mique. La présente étude considère ces rapports au Canada au niveau national, sous-national et local, en exminant les performances des entreprises inventives indigènes et étrangères. Les résultats indiquent (1) qu'au Canada les entreprises indigènes et inventives diffèrent de leurs analogues étrangers: en général elles sont plus petites, ont plus tendance à consister en équipes ?inven-teurs, sont plus susceptibles de développer les inventions produites, produisent une plus grande part des inventions canadiennes, et sont en train ?augmenter leur rôle dans les industries canadiennes; et (2) que le déclin de ?esprit ?invention dans les entreprises dirigées par les américains a affecté défavorablement les deux villes les plus grandes au Canada, ainsi que la partie centrale du pays, pendant les années 1980. Mots-clés: invention, Canada, propriétéétrangère, technologie, produit  相似文献   
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Ancient mortars from northern Italy, dating from the fifth to the seventeenth century AD, were examined in order to formulate an hypothesis regarding the origin of the white lumps often observed in these mortars and in other samples of the same geographical provenance. Various characterization techniques were employed, including scanning electron microscopy, X-ray powder diffraction and Fourier transform infrared (FTIR) and micro-FTIR spectroscopy.  相似文献   
133.
Glow discharge optical emission spectrometry (GDOES) has been used for obtaining calibration curves for copper, tin, lead, silver, antimony, arsenic, zinc and iron from standards including copper-base alloys (Cu 61.33-99.95%) and from bronze Punic coins. The GDOES results were calibrated using atomic absorption spectroscopy with inductively coupled plasma atomization (ICPAAS) to analyse the standards and coins. For all these materials, the results show that via GDOES it is possible to obtain reliable and reproducible calibration curves for copper, tin, lead, zinc and iron with a linear behaviour as a function of the content. The quantitative GDOES and ICPAAS data for the coins have been also compared with those obtained via X-ray fluorescence (XRF) and it is shown that GDOES, ICPAAS and XRF agree well with one another considering that the bronze coins are inhomogeneous to some degree. As an example of GDOES analytical features, a depth concentration profile through a thin bronze patina is shown and briefly discussed.  相似文献   
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In Part I of this paper (Smith and Hsieh, 1997) a programming formulation of steady states was developed for gravity-type interactive Markov chains in terms of their associated spatial-flow chains. These results are here applied to analyze the stability properties of interactive Markov chains. In particular, the objective function for this programming formulation is shown to constitute a Lyapunov function for an appropriately defined continuous-time version of spatial-flow chains. The Lyapunov stability properties of these spatial flows are then shown to yield corresponding stability properties for the continuous-time versions of interactive Markov chains. In particular, these processes always exhibit global convergence to steady states. Finally, it is shown that when steady states are unique, these convergence results are inherited by those interactive Markov chains that are 'sufficiently close' to their continuous-time versions.  相似文献   
138.
The 1689 Toleration Act allowed Protestant dissenters freedom to worship in public, but it was only a limited toleration and dissenters continued to suffer discrimination. This article examines the experience of Quakers in one important area, the Anglican monopoly in teaching. Although the prosecution of unlicensed teachers was patchy, localised, and dependent upon the hostility and zeal of particular individuals, few dissenters escaped harassment. Moreover, Friends appear to have suffered more severely because of the particular dislike that they still provoked and their unwillingness to compromise which often led to imprisonment. The growth in High Church feeling during Anne's reign led to a more rigorous enforcement of the existing statutes and the passing of the Schism Act (1714). The consequences of an Anglican educational monopoly have not been properly considered by historians largely from the assumption that the Schism Act was fatally compromised by the death of Queen Anne, and because little attention has been paid to the continued harassment of dissenters after toleration who attempted to teach. The Schism Act was repealed in 1719, but freedom for Quakers and other dissenters to teach had already been achieved largely through the courts.  相似文献   
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The transformation of the Indus Civilization   总被引:1,自引:0,他引:1  
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