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71.
John N. H. Britton 《The Professional geographer》1981,33(1):36-47
The technological underdevelopment of secondary manufacturing in Canada is inferred from patterns of trade, industrial structure, and the range of industrial functions performed within firms in Canada. These patterns are explained by reference to the behavior of foreign subsidiaries that have major direct and indirect effects on the linkages and developmental potential of the Canadian industrial system. Canadian manufacturing is found to have a low level of innovative capability because of inadequate R & D and product and design engineering in foreign and domestic firms. In view of the strong need for new policy initiatives, the components of a techno-industrial strategy are evaluated. 相似文献
72.
Richard B. Wheeler John B. Anderson Rudy R. Schwarzer Claudia L. Hokanson 《Environmental Geology》1980,3(3):163-175
Sediments are the ultimate sink for contaminants in the marine environment, and physical processes of sedimentation influence
the distribution and accumulation of these contaminants. Evaluation of contaminant levels in sediments is one approach to
assessing environmental impact; data interpretation depends on consideration of sediment texture and mineralogy, however,
which profoundly influence chemical composition. In this study, comparison of potentially contaminated sediments from the
production field with control populations was done only within the context of similar (as to texture and organic carbon and
carbonate content) sample groups as determined by cluster analysis. Ba, Cd, and Sr are identified as contaminants. Supported
by the identification of a well-crystallized expandable clay—possibly bentonite—drilling fluids are a potential source of
Ba. Ba and Sr may be unnaturally high because of their abundance in discharged produced formation waters, but may also be
naturally controlled by the unique faunal assemblage associated with the structures. Cd is probably derived from corrosion
of the structures and assorted debris on the seafloor. In general, contamination is limited to an area within 100 m of the
platforms. Furthermore, substantial erosion around platforms has probably effectively removed and dispersed the bulk of the
contaminants introduced into the marine environment by the offshore exploration/production operations. 相似文献
73.
This paper considers issues of authenticity as they apply to the evolution of farmers' markets in New Zealand. Following a discussion of the nature of authenticity and its deployment by farmers' market organisations in several jurisdictions, a two‐part case study is presented. An analysis of the strategies adopted by Farmers' Markets New Zealand to ‘protect its brand’ nationally and an examination of the disputation of authenticity in the Marlborough Farmers' Market reveals the potential of the ‘authenticity project’ to be a lightning rod for heightened tension and the fracturing of the relationship between competing interests in New Zealand farmers' markets. 相似文献
74.
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76.
Richard G. Klein Kathryn Cruz-Uribe David Halkett Tim Hart John E. Parkington 《Quaternary Research》1999,52(3):393
Boegoeberg 1 (BOG1) is located on the Atlantic coast of South Africa, 850 km north of Cape Town. The site is a shallow rock shelter in the side of a sand-choked gully that was emptied by diamond miners. Abundant coprolites, chewed bones, and partially digested bones implicate hyenas as the bone accumulators. The location of the site, quantity of bones, and composition of the fauna imply it was a brown hyena nursery den. The abundance of Cape fur seal bones shows that the hyenas had ready access to the coast. Radiocarbon dates place the site before 37,000 14C yr ago, while the large average size of the black-backed jackals and the presence of extralimital ungulates imply cool, moist conditions, probably during the early part of the last glaciation (isotope stage 4 or stage 3 before 37,000 14C yr ago) or perhaps during one of the cooler phases (isotope substages 5d or 5b) within the last interglaciation. Comparisons of the BOG1 seal bones to those from regional Middle Stone Age (MSA) and Later Stone Age (LSA) archeological sites suggest (1) that hyena and human seal accumulations can be distinguished by a tendency for vertebrae to be much more common in a hyena accumulation and (2) that hyena and LSA accumulations can be distinguished by a tendency for hyena-accumulated seals to represent a much wider range of individual seal ages. Differences in the way hyenas and people dismember, transport, and consume seal carcasses probably explain the contrast in skeletal part representation, while differences in season of occupation explain the contrast in seal age representation. Like modern brown hyenas, the BOG1 hyenas probably occupied the coast year-round, while the LSA people focused their coastal visits on the August–October interval when nine-to-eleven-month-old seals were abundant. The MSA sample from Klasies River Mouth Cave 1 resembles BOG1 in seal age composition, suggesting that unlike LSA people, MSA people obtained seals more or less throughout the year. 相似文献
77.
The Random Forests (RF) algorithm is a machine learning method that has recently been demonstrated as a viable technique for data-driven predictive modeling of mineral prospectivity, and thus, it is instructive to further examine its usefulness in this particular field. A case study was carried out using data from Catanduanes Island (Philippines) to investigate further (a) if RF modeling can be used for data-driven modeling of mineral prospectivity in areas with few (i.e., <20) mineral occurrences and (b) if RF modeling can handle predictor variables with missing values. We found that RF modeling outperforms evidential belief (EB) modeling of prospectivity for hydrothermal Au–Cu deposits in Catanduanes Island, where 17 hydrothermal Au–Cu prospects are known to exist. Moreover, just like EB modeling, RF modeling allows analysis of the spatial relationships between known prospects and individual layers of predictor data. Furthermore, RF modeling can handle missing values in predictor data through an RF-based imputation technique whereas in EB modeling, missing values are simply represented by maximum uncertainty. Therefore, the RF algorithm is a potentially useful method for data-driven predictive modeling of mineral prospectivity in regions with few (i.e., <20) occurrences of mineral deposits of the type sought. However, further testing of the method in other regions with few mineral occurrences is warranted to fully determine its usefulness in data-driven predictive modeling of mineral prospectivity. 相似文献
78.
V.V. Gopalakrishna F. Durand K. Nisha M. Lengaigne T.P. Boyer J. Costa R.R. Rao M. Ravichandran S. Amrithash L. John K. Girish C. Ravichandran V. Suneel 《Deep Sea Research Part I: Oceanographic Research Papers》2010,57(6):739-754
The southeastern Arabian Sea (SEAS), located in the Indian Ocean warm pool, is a key-region of the regional climate system. It is suspected to play an important role in the dynamics of the Asian summer monsoon system. The present study reports the salient features derived from a newly harvested observational dataset consisting of repeated fortnightly XBT transects in the SEAS over the period 2002–2008. The fortnightly resolution of such a multi-year record duration is unprecedented in this part of the world ocean and provides a unique opportunity to examine the observed variability of the near-surface thermal structure over a wide spectrum, from intra-seasonal to interannual timescales. We find that most of the variability is trapped in the thermocline, taking the form of upwelling and downwelling motions of the thermal stratification. The seasonal variations are consistent with past studies and confirm the role of the monsoonal wind forcing through linear baroclinic waves (coastally-trapped Kelvin and planetary Rossby waves). Sub-seasonal variability takes the form of anomalous events lasting a few weeks to a few months and occurs at two preferred timescales: in the 30–110 day band, within the frequency domain of the Madden–Julian oscillation and in the 120–180 day band. While this sub-seasonal variability appears fairly barotropic in the offshore region, the sign of the anomaly in the upper thermocline is opposite to that in its lower part on many occasions along the coast. Our dataset also reveals relatively large interannual temperature variations of about 1 °C from 50 to 200 m depth that reflect a considerable year-to-year variability of the magnitude of both upwelling and downwelling events. This study clearly demonstrates the necessity for sustained long-term temperature measurements in the SEAS. 相似文献
79.
Two widely-used techniques to estimate the volume of remaining oil and gas resources are discovery process modeling and geologic assessment. Both were used in a recent national assessment of oil and gas resources of the United States. Parallel estimates were obtained for 27 provinces. Geological-based estimates can typically see into areas not available to discovery process models (that is areas with little or no exploration history) and thus, on average, yield higher estimates. However, a linear relation does exist between the mean estimates obtained from these two methods. In addition, other variables were found in a multiple regression model that explained much of the difference. Thus, it is possible to perform discovery process modeling and adjust the estimates to yield results that might be expected from geological-based assessments. 相似文献
80.