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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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Discovery of the uses and later the invention of fire-making are fundamental to humanity. Following reports over the last decade of traces of fire found on Lower Pleistocene archaeological sites in eastern Africa, the dating of the control of fire by hominids has become a controversial issue. In this paper we critically review the contexts and, in the light of a battery of archaeometric techniques, the nature of reported instances of fire from Koobi Fora and Chesowanja in Kenya, and from Gadeb and the Middle Awash in Ethiopia. We conclude with a discussion of the roles fire may have played in the lifeways of early Pleistocene savanna-living hominids.
Résumé La découverte des usages du feu et ensuite de sa préparation est fondamentale pour l'humanité. Suite à des rapports au cours de la dernière décennie signalant des traces de feu relevées dans des sites archéologiques du Pléistocène inférieur dans l'est de l'Afrique, la datation du contrôle du feu par les hominiens est devenu une source de controverse. Dans cet article, nous révisons d'un oeil critique les contextes et la nature des cas de feu signalés à Koobi Fora et à Chesowanja au Kenya, et à Gadeb et dans l'Awash moyen en Éthiopie, à la lumière d'une suite de techniques archéometriques. Suit en conclusion une discussion sur les rôles qu'aurait pu jouer le feu dans les modes de vie des hominiens vivant dans les savannes du Pléistocène inférieur.
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A number of investigations have been undertaken by the New South Wales Water Resources Commission to determine the regional and compound effects of large scale extractive industries on the stability of the Hunter River, New South Wales. Sedimentologic studies of bed material suggest that the Hunter River upstream of Denman has an armoured gravel bed that is immobile during regulated releases from Glenbawn Dam but is disrupted by moderate but less than bankfull flows. Annual bedloadyields have been computed by the bedload rating-flow duration technique for five river gauging stations. Approximate sand and gravel budgets for selected reaches of the Hunter River demonstrate that the present annual extraction rate from temporary sediment storages within the channel greatly exceeds the transport rate upstream of Denman and is approximately equal to the transport rate downstream of Denman. River degradation is imminent if extractive industries continue operating in the channel of the Hunter River  相似文献   
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