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41.
This article reports a generalised and systematic approach to the thermoluminescence (TL) dating of samples which suffer from anomalous fading. We hypothesise that the TL signal from each mineral phase is composed of a stable and an unstable portion. The decay of the unstable TL is accelerated thermally, until only stable TL remains. The dating is then carried out on this stable signal. The results, on four known-age, coeval samples, exhibiting gross anomalous fading (25-50% loss over a few days), indicate that many, if not all, samples may successfully be dated with this approach. 相似文献
42.
43.
ABSTRACT This paper investigates the implication of production-technology uncertainty for the exclusion theorem. The paper presents the result that the risk-averse firm facing production technology uncertainty prefers an intermediate location to avoid risk under certain conditions. The firm chooses an intermediate location (over a corner location) particularly if its degree of risk aversion overwhelms the inherent convexity of profit with respect to location. The latter depends, in turn, on the structure of production technology characterized by the elasticity of substitution and returns to scale parameters. 相似文献
44.
ABSTRACT This paper examines the role of the structure of transportation rates in the Weber-Moses triangle model. It shows that, in Zeigler's analysis, the appearance of the price elasticities of demand for inputs actually vanish by a simple application of the envelope theorem. Applying comparative statics analysis, we show when transportation rates are a function of quantity and distance, the assumptions that the production function is homogeneous of degree one and the transportation rates elasticities with respect to quantity and distance are constant are not sufficient to insure that the optimum location is independent of the level of output. This result is significantly different from that obtained by either Miller and Jensen or Zeigler. 相似文献
45.
Geoffrey K. Turnbull 《Journal of regional science》1988,28(4):541-562
ABSTRACT. This paper incorporates an exogenous taxing and service-providing public sector into a dynamic residential land-use model in order to examine how local-government fiscal policies alter the pace and pattern of residential development. The model is used to derive the comparative-dynamic responses to variations in the income, sales, and property taxes and public-service time paths. The results show how tax and expenditure effects systematically depend upon the anticipated relative growth rates in rents to alternative uses and vary across locations within a given urban area as well as across urban areas themselves. 相似文献
46.
ABSTRACT. This paper introduces the household interactive variable input-output (HIVIO) model to measure the effect of cost variation on industrial outputs. The model produces a variety of cost elasticities that separate out impacts on industrial prices, imports, and outputs, with “own” and “cross” elasticity components. Like the conventional input-output multipliers, these cost elasticities can be useful parameters to evaluate the substituting behavior of firms and consumers. By using the 1980 Korean input-output transactions table, we find the wage and import price effects on industrial prices, outputs, and import demands. 相似文献
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48.
Mohammed K. Fazel 《Iranian studies》1988,21(3-4):37-51
49.
"This paper presents a two-sector dynamic model of regional population change. The model contains a migration equation, an earnings equation, and an amenity equation for each region. In the context of this model, migration is seen as a disequilibrium process through which the regional populations move towards equilibrium positions. Migration occurs when one region is perceived to be superior to the other on the basis of its earnings and amenity levels. Equilibrium is achieved when population movements between the regions eliminate any differences in their relative attractiveness. A comparative-static analysis of the model is presented to analyze the effects of policy changes and exogenous shocks on the distribution of population among the regions." The geographical focus is on the United States. 相似文献
50.