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31.
ABSTRACT. Traditional models of regional diversification do not capture the trade-off between stability and living standards. In this paper, we characterize regions as open activity models subjected to both productivity and price shocks. We then partially rank small diversification policies by the direction in which they point away from the current industrial structure in mean-variance space. Some general patterns emerge. In particular, diversification for regional self-sufficiency and away from regional comparative advantage may be undesirable. 相似文献
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33.
Ashok V. Desai 《Development and change》1990,21(4):723-749
This paper analyses the results of a survey of twenty-four recent cases of technology imports into India. Over the last thirty years, large firms in Indian industry have come under increasing competitive pressure from small firms which pay lower wages and which are also favoured by government policy. Most small firms obtain technology through informal channels within the country. But some import technology; and larger firms import it in their defence against competition from small firms. Larger firms, with a history and a reputation, have better access to technology from abroad; smaller firms often go through an extensive search before they find a willing technology supplier. Irrespective of size, firms that import technology within their own specialization are observed to put more effort into technology choice, absorption and adaptation. Indian policies of across-the-board import substitution, by promoting diversification into new products developed abroad, tend to discourage specialization and hence to encourage technology imports and to work against technology absorption and innovation. 相似文献
34.
Joseph R. Desloges 《The Canadian geographer》1990,34(2):98-109
Changes in the grain-size distribution and the lithologi-cal I mineralogical properties of sandy-gravel sediments are used to discriminate between sources for the alluvial valley-fill of Bella Coola River, coastal British Columbia. Spatially variable bedrock sources, ranging from highly resistant quartz monzonites to easily weathered basalts, yield sediments that reflect parent rock characteristics. Local increases in the D95 fraction of bulk gravel samples and the D50 fraction of sand samples can be related to inputs from steeper, heavily glaciated tributaries, or those underlain by fractured basalts of the Fraser Plateau. Where there are similarities in the grain-size properties of the source and the sampled deposit, however, grain-size information alone cannot be used to discriminate between sources. The lithology of Bella Coola alluvium shows a close correspondence with the general distribution of rock types in the basin, suggesting proportional contributions from most tributary sources over the long term. However, sand samples from the floodplain have a mostly volcanic affinity, indicating the dominance of sediment derived from headwater tributaries underlain by this rock type. Admixture of plutonic source sediments is evident in lower Bella Coola River adjacent to alluvial fans, heavily glaciated tributary creeks or rock walls comprised mainly of quartz monzonite. Les changements dans la granulometrie et les proprietes lithologiques et mineralogiques des sediments de gravel sablonneux servent d differencier les sources des depéts alluviaux de la Riviere Bella Coola sur la céte de la Colombie-Britannique. La variation spatiale des sources fondamentales donnent des sediments qui refletent les caracteristiques de la roche-mbe variant des quartz rnonzonites très résistants aux basaltes superficiellement altérés par les agents atmospheriques. Les augmentations locales dans la fraction D95 des echantillons de gravel et la fraction D50 des echantillons de sable peuvent être reliees la contribution des tributaires aux pentes plus escarpees et fortement glaciaires ou ceux qui traversent les basaltes fractures du Plateau Fraser. Cependant, quand il y a des similitudes dans la granulometrie de la source et le dépôt-échantillon, l'information granulometrique seule ne peut pas 6tre employee pour differencier les sources. La lithologie des alluvions de Bella Coola montre une correspondance avec la distribution générale des types de roches dans le bassin, suggérant des contributions proportionnelles des sources tributaires a long terme. Cependant, les échantillons de sable des plaines sujettes à inondations ont en grande part une affinité volcanique, indiquant que la dominance du sédiment provient des tributaires qui traversent ce type de roche. Une addition de sediments de sources plutonique est evidente dans le bas de la Riviere Bella Coola adjacent aux eventails alluviaux, aux ruisseaux tributaires affect& par une forte glaciation, ou aux murs de roches qui comprennent principalement des quartz monzonites. 相似文献
35.
García-Heras Manuel Agua Fernando Madiquida Hilario Fernández Víctor M. de Torres Jorge Villegas María-Ángeles Ruiz-Gálvez Marisa 《African Archaeological Review》2021,38(2):297-318
African Archaeological Review - A set of beads made of glass, gastropod mollusk shell, and fishbone from a Swahili occupation level on Ibo Island (northern Mozambique) is dated to the eleventh and... 相似文献
36.
Joseph Shapiro 《政策研究杂志》1994,22(1):123-132
The Americans with Disabilities Act was pushed through Congress with far less attention from the media than has accompanied other major civil rights bills. This was part of a deliberate and unconventional strategy by disability rights lobbyists who believed that media portrayals of disability were so cliched that journalists would impede, not further, the public's understanding of disability rights issues. Despite the success of the strategy, there is a price to pay for having been a 'stealth' civil rights movement: Now that the law is in place, disabled people face a backlash from Americans who neither understand the ADA nor the need for civil rights protection for disabled people. 相似文献
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V. ARGYROPOULOS 《Archaeometry》1995,37(2):271-285
The study addresses the chemical variations for Roman Samian wares manufactured during various periods at different workshops within the Lezoux production centre. Instrumental neutron activation analysis and inductively coupled plasma spectrometry were used to determine the chemical constituents of the pottery. The two techniques were evaluated based on the capacity of each to identify the same compositional groups for Lezoux Samian with the use of multivariate statistics. The compositional analysis redefines and clarifies how potters used the clay sources at the site to produce fine wares. The results indicate that the majority of potters from different workshops at Lezoux shared the same clay source during the second century AD. 相似文献
39.
Blue glass trade beads from well-dated late seventeenth- to early twentieth-century sites and collections have been analysed non-destructively by instrumental neutron activation analysis. The beads display enough variations in their elemental contents to allow us to characterize the different chemistries. The implication of these results is that similar chemical analyses of blue beads from undated archaeological sites may be used to help date the sites, since each bead chemistry has a specific earliest period. 相似文献
40.
Fifty-three copper-based metal fragments, recovered from the Robitaille site in southcentral Ontario, were analysed by neutron activation to establish their chemical make-up and to sort them by their trace elemental chemistries. Three different European copper samples, one brassy copper and 48 brass samples with five different chemistries were found. As few as eight trading actions may account for all of the recovered European metal fragments. 相似文献