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Australia's uranium comprises about 18% of the Western World's reasonably assured reserves. Mining, milling and export have been proceeding since the federal government's decision in August 1977. The timetable for development of several other projects involves matters such as environmental issues, approval by the aboriginal people and mining practice policies. The author discusses the background to present uranium mining in Australia and examines the industry's likely international significance.  相似文献   

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The papers in this issue of Resources Policy are devoted to the minerals industry of Canada, prepared by specialists in that country. The papers have all been edited by Professor G.J.S. Govett (of the Department of Geology, University of New Brunswick at Fredericton, New Brunswick), and M.H. Govett (minerals economist).  相似文献   

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The sharp decline in Malaysia's tin output has become a matter of serious concern. The mining industry has blamed ‘penal’ tax rates for the decline in development, but more important in discouraging new investment and prospecting are difficulties in obtaining new mining leases, and the insecurity created by government plans to restructure asset ownership so as to increase indigenous Malay participation.  相似文献   

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During the past decade, Norway has become an important oil and gas producer. Annual production is six times national consumption. Development policies of the national government have been cautious, and future policies will probably follow a similar pattern. The government recently opened offshore areas poleward of 62°N latitude, a decision likely to have a significant impact on Norway's future as an oil producer. Norway maintains a tight reign on foreign oil company participation, domestic downstream processing of crude, oil company taxation and oil revenue investment within the national economy. Norway's large inflow of oil-related capital investments and production revenues have contributed to significant inflation and to changes in local labour supplies. Norway has always used its petroleum industry to further the country's overall development goals, a policy that will continue in the years ahead.  相似文献   

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After the dramatic increase in prices for uranium over the 1972–1975 period, prices have declined in real terms. This article examines the future supply, demand and price trends for uranium, and predicts that a situation of excess supply will result in the 1980s, bringing a continuing decline in real prices, unless Canada and other net exporters, most importantly Australia, agree to restrict supplies in order to maintain the price of uranium at its present level in real terms. Such a policy would have substantial benefits for Canada and other net exporters of uranium.  相似文献   

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One hundred and five parents and nonparents responded to a questionnaire consisting of evaluative ratings (general evaluation, social status and safety concern) of six familiar residential neighborhoods; ratings of the traffic accident risk children in the age ranges 2–4, 5–6, 7–9 and 10–12 years run in these neighborhoods; and, finally, ratings of the strengths attributed to factors as causes of traffic accidents (environment, children, parents, drivers and chance). Across neighborhoods and age ranges of children, risk perceptions were found to be related to the rated strengths of the causes. Low-traffic volume neighborhoods were perceived as less risky and were attributed as less strong causes than high-traffic volume neighborhoods were. Perceived risk increased with age of child to a maximum, then decreased. The same relationship with age was found for the attributed causes environment and drivers. The strength of parents as cause was rated to decrease while the strength of child as cause was rated to increase with age. Chance was rated as the weakest cause and the rated strength did not vary across neighborhoods or age. Neither parentship nor gender, singly or in combination, had any clear effects. For parents and nonparents alike the general evaluation of the neighborhoods was influenced by safety concern but not by the particular aspect investigated, i.e. perceived traffic accident risk to children.  相似文献   

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The business rationality of the CMEA mineral traders is bound by several characteristics of mineral production under central planning and by the mechanics of foreign trade monopoly. These characteristics include aspects such as: priority of national economic goals over trading strategies of the Foreign Trade Organisations (FTOs) in Eastern Europe; balance-of-payment problems; the organizational complexities and the weakness of the incentive mechanism, as well as the lack of an appropriate performance criterion. It is suggested that the 30 mineral trading FTOs in the CMEA tend to perform in a manner comparable to marketing departments of the Western mineral industries but are at a clear disadvantage when compared with ‘stand alone’ Western intermediaries making profits through risk taking and abhoring bureaucracy and rigidity in management.  相似文献   

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How adults and children come to understand, represent and behave within their spatial environment are topics of great interest to geographers, psychologists, environmental planners and laypeople. Considerable research and theory has been published on these and related topics. In this paper, we will review some of what is known and theorized about spatial cognition and then consider elements of our research program on the acquisition of spatial knowledge. We focus on two intimately related topics. The first is the development of a conceptual model of the knowledge structures and processes associated with acquiring, representing and accessing knowledge of a given environment. The conceptual model forms the basis for a formal computational process model intended as a simulation of actual knowledge and performance in way finding tasks. The second emphasis is an in-depth case study of the acquisition of spatial knowledge. The case study focuses on a single child acquiring knowledge of a lengthy route through an unfamiliar suburban neighborhood. It is presented as an empirical test of certain assumptions embodied within the conceptual model.Before introducing the conceptual model and the case study, we first review the state of current theory and data on spatial cognition and identify four central issues confronting researchers in this field. This review provides a necessary context for describing and evaluating our program of research. The second section of this paper discusses elements of the conceptual model and its relationship to other formal computational models. The third section considers specific hypotheses about the acquisition and representation of spatial knowledge and tests of these hypotheses from the single in-depth case study. The final discussion section of this paper is a reconsideration of the four issues raised in the first section and necessary and proposed extensions of the current research.  相似文献   

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The ability of six-year-old children to combine perspectives of spatial layouts in their own neighbourhood was assessed. The children were asked to imagine themselves as being at a particular reference site and to decide which of two landmarks was closer to the site. From a theoretical point of view, one should not expect six-year-olds to have acquired projective and Euclidian concepts. Nevertheless, the judgements were internally consistent and tended to be veridical. This sensitiveness to relative and absolute accuracy was interpreted as a step towards a general cognitive capacity, governing the representation of spatial relations. Distances to the home were underestimated relative distances to other landmarks. Also estimations from the home tended to be more accurate than estimations from other reference sites. These results suggest that the home acts as a central reference point in children's mental representation of the environment.  相似文献   

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This study explores the feasibility and utility of integrating environmental DNA (eDNA) assessments of species occurrences into the United States (U.S.) Geological Survey’s national streamgage network. We used an existing network of five gages in southwest Idaho to explore the type of information that could be gained as well as the associated costs and limitations. Hydrologic technicians were trained in eDNA sampling protocols and they collected samples during routine monthly visits to streamgages over an entire water year (2016). We analyzed the eDNA in the filtered water samples to determine the presence of two fish species: bull trout and rainbow trout. We then modeled the spatiotemporal distribution of each species using discharge and temperature data. To assess the influence of the spatial distribution of the gages on the biological information obtained, we also collected eDNA samples from locations between the gages three times during the water year. We found eDNA monitoring at the five gages provided meaningful information about the distribution of both species, especially when detection probabilities accounted for variations in temperature and discharge. Sampling between the gages provided additional information about bull trout distribution — the rarer of the two species. Our study suggests the integration of eDNA sampling into a streamgage network is feasible and could provide a novel and powerful source of biological information for riverine ecosystems in the U.S.  相似文献   

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