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21.
Digital analysis of Landsat data is applied to up-dating land cover maps for the Goondiwindi district of southern, inland Queensland. The imagery was paired with climax cover maps obtained from land systems reports with analysis conducted separately for each of three climax cover types (open forest, woodland and open woodland). Computer classification using this approach produced readily interpreted and reliable results. This work demonstrates that Landsat can be used in conjunction with existing, land systems derived maps to produce data that combine the advantages of two approaches to environmental survey, the former being based on current land cover/land use and the latter on the original environment and its land use potential. 相似文献
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A number of public policy issues have been discussed in this article, the most important of which are: 1. Small business would not need special consideration if our economy were basically a competitive one. 2. A large and growing segment of our economy has sufficient market and political power to make our economy basically non-competitive. 3. Small firms tend to provide price competition, to lead in the development of new products and processes, and to generate new innovations and new employment. 4. Government policy tends to create artificial economies of scale, giving an unwarranted advantage to the very large firm. As a first approximation, a policy of government neutrality on firms of varying size is needed. But, because of discriminations which already exist which favor large firms over small firms, special small business programs may be necessary to provide an equitable policy base. Unfortunately, programs designed to benefit all business, like the investment tax credit, tend to primarily benefit larger firms (Berney, 1979). This is the case for two reasons. First, there is a basic difference in production relationships: large firms tend to be more capital intensive and small firms more labor intensive. Second, the more complex a rule or regulation, the more costly it is for small business to use it. Consequently, even the employment tax credit, which should benefit the small firm is not used by them. Instead, it tends more to benefit the larger firm. Neutrality, as a governmental policy, would appear to demand different treatment for firms of varying size. As an example, the “regulatory flexibility” concept applies different standards to different sized firms so that the burden of regulation is more equitably distributed. The concept of encouraging or requiring financial institutions and other lenders to establish “dual prime rates” is a further example. Since small firms appear to have much higher debt to equity ratios and rely more heavily on shorter-term bank credit, they are more heavily burdened by a tight money policy which forces increases of interest rates. Thus, dual prime rates help to spread the burden of rising interest costs more equally. As many people prefer to work for themselves, equalizing the burden of government policy could only serve to increase the basic growth rate for small business, thus providing an easier start for entrepreneurs and would encourage a more rapid rate of economic growth. None of these discussions, however, argues that small business should be protected from failure. The more efficient firms will succeed and prosper, and the least efficient will not. Many currently successful entrepreneurs learn how to improve their production processes or managerial skills from their failures. What is being recommended as a first step is that government should concentrate on equalizing burdens and benefits in order to achieve true neutrality. If private economies of scale do indeed exist, new firms must grow to survive; what the government should not create are artificial economies of scale with public policy. A strong argument for further action can also be made: it appears that significant external benefits are produced by an economic system with a dynamic small business sector. Since these benefits go to society as a whole rather than entrepreneurs alone in the form of increased profits, a freely operating market without government assistance does not generate as many new small businesses as would be optimal for our society. To internalize the benefits that come from small business, governmental programs need to be devised to increase the rate of return on new, innovative small businesses. Should this happen, we could then anticipate increased rapid rates of innovation and technological change, more rapid rates of employment growth, expanded price competition in all sectors of the economy, and improved export capabilities, in short, true flexibility in our capitalistic system. 相似文献
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AAS, FE and OES are each used in the analysis of thirteen samples of fragments of window glasses from three Catalan Gothic churches: Sta. Maria del Mar (Barcelona, Spain), Pedralbes Monastery (Barcelona, Spain) and Girona Cathedral (Spain). Two kinds of stained window glass are found. Special attention is paid to Co/Cu, Co/Ni and Cu/Ni ratios for blue glasses and Mn/Cu and Fe/Cu ratios for red glasses. 相似文献
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Anthony E. Marks 《African Archaeological Review》1987,5(1):79-92
Excavations by the joint University of Khartoum/Southern Methodist University Butana Project in the area just north of Khashm el Girba on the upper Atbara River have uncovered a series of preceramic and early ceramic occupations by hunters and gatherers which date fromca 10,000 bp toca 6200 bp. The earlier sites show no direct relations with those of similar age in the northern Sudan, while the later, early ceramic sites show only minor similarities with contemporary occurrences in the central Nile Valley. Thus, it appears that the upper Atbara River Valley played no role in the development of the Khartoum Mesolithic and that Nilotic influences were late reaching the eastern Sudan.
Résumé Des fouilles entreprises par le projet Butana dirigé en commun par l'université de Khartoum et le Southern Methodist University dans la région juste au nord de Khashm el Girba sur le cours supérieur de l'Atbara, ont découvert une série d'occupations précéramiques et céramiques anciennes de chasseurs-cueilleurs, qui datent deca 10,000 bp àca 6200 bp. Les gisements les plus anciens ne semblent pas avoir eu de relations directes avec ceux de la même période dans le nord du Soudan, tandis que les gisements plus tardifs à céramiques ne montrent que de petites analogies avec des occupations contemporaines dans la vallée centrale du Nil. Il semble donc que la haute vallée de l'Atbara n'a joué aucun rôle dans le développement du Mésolithique de Khartoum et que des influences nilotiques n'atteignirent que bien plus tard le Soudan oriental.相似文献
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The upper Mersey Valley was glaciated on three occasions during the Pleistocene. The youngest, Rowallan Claciation, probably commenced after 28000 years B.P. The maximum ice limit was attained before 13500 years B.P., and retreat occurred before 10000years B.P. Deposits associated with Rowallan Glaciation are weakly weathered chemically. They overlie moderately weathered deposits that were formed during the Arm Glaciation, which is inferred from relative dating data to have occurred before the Last Interglacial Stage. North of the deposits and ice limits of the Arm Glaciation extremely weathered tills and rhythmites occur. They were formed by ice of the Croesus Glaciation which is inferred to be of Early Pleistocene age or older. 相似文献
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