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11.
12.
This paper examines the theoretical implications of quantity-discounted transportation rates on the optimum location decision of the firm. It shows that the linearly homogeneous or homothetic production function is not a sufficient condition for the independence between the optimum location and the output level, unless (i) the elasticities of transportation rates with respect to quantity shipped are constant and identical, and (ii) the ratios of marginal products 60 the marginal transportation costs are equal for each input. 相似文献
13.
In order to carry out strontium (Sr) isotope analysis, glass artefacts from South Asia were sampled with portable laser ablation (pLA), a relatively novel sampling technique that leaves damage invisible to the naked eye. Subsequently, thermal ionization mass spectrometry (TIMS) was used to obtain Sr isotope ratios after sample dissolution and separation. In this study, the goal was twofold: to determine whether the measurements of Sr isotope ratios were impacted by using a portable laser as a sample tool; and to assess the pertinence of using Sr isotope ratios to provenance Indian glass. Despite a deterioration in the precision of the measurement of the Sr isotope ratios for artefacts sampled with pLA compared with the traditional sampling method, the Sr isotope ratios of certain Indian glass are so different that this does not affect their separation but a comparison of data sets obtained using standard methods and pLA might be challenging. 相似文献
14.
ABSTRACT. The problem of locating a point that is as far as possible from arcs and nodes of a network is investigated. Each arc or node may have a different multiplicative factor (weight) for its distance. A graphical solution approach, as well as a computational algorithm, is presented. 相似文献
15.
David O. Rafter 《European Planning Studies》1996,4(2):225-236
The concept of sustainability has become a significant consideration in planning in Europe and the US. At both the international and the national level, urban planners and policymakers have developed a package of policies designed to produce sustainable growth and development. In transport, this has been interpreted to mean that we need to increase accessibility while we reduce mobility by shifting trips from automobile to walking, bicycle or public transport modes. Using this criteria, the latest Dublin transport plan has been found to be only partially effective. Similar to many American transport plans, the DTI has opted for the infrastructure‐related sustainability policies and avoided the less popular economic disincentives. 相似文献
16.
QUANTITATIVE ANALYSIS OF COPPER-TIN BRONZES BY MEANS OF GLOW DISCHARGE OPTICAL EMISSION SPECTROMETRY
Glow discharge optical emission spectrometry (GDOES) has been used for obtaining calibration curves for copper, tin, lead, silver, antimony, arsenic, zinc and iron from standards including copper-base alloys (Cu 61.33-99.95%) and from bronze Punic coins. The GDOES results were calibrated using atomic absorption spectroscopy with inductively coupled plasma atomization (ICPAAS) to analyse the standards and coins. For all these materials, the results show that via GDOES it is possible to obtain reliable and reproducible calibration curves for copper, tin, lead, zinc and iron with a linear behaviour as a function of the content. The quantitative GDOES and ICPAAS data for the coins have been also compared with those obtained via X-ray fluorescence (XRF) and it is shown that GDOES, ICPAAS and XRF agree well with one another considering that the bronze coins are inhomogeneous to some degree. As an example of GDOES analytical features, a depth concentration profile through a thin bronze patina is shown and briefly discussed. 相似文献
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18.
O.F.G. SITWELL 《The Canadian geographer》1993,37(4):332-351
The special number of the Canadian Geographer devoted to West Edmonton Mall raises important questions, notably that of the relative status, as values, of work (seen historically as fundamental to our culture), and of leisure, perceived, albeit controversially, as being embodied in wem. In preparing to present my principal thesis, I review recent reinterpretations of human behaviour advanced by workers in the fields of symbolic interaction and the sociology of knowledge. These schools ha ve given rise to the concept of, though not the term, functional religion. The meaning of this concept is close to that of ideology; a comparative analysis of the two terms justifies using the former. A survey of recent work by geographers who approach religion from a functional point of view closes the second part of the paper. In the course of this review the relative status of work and leisure emerges as a significant issue. The view of leisure as a norm presented in the third part of the paper is that advocated by Pieper, Huizinga, and de Grazia. They argue that the Classical view, according to which human life finds its meaning in activities that are carried on for their own sake (e.g., games), rather than in those pursued for the material rewards they offer, is correct. Following their lead, and in opposition to both Marxists and Liberals, I argue that the adoption of leisure as a fundamental value would provide a more satisfactory foundation for our culture than work has to this point. Le numéro spécial du Géographe canadien consacréà?étude du West Edmonton Mall soulève plusieurs questions importantes, notamment celle du statut relatif, comme valeur, du travail (valeur-clé historiquement dans notre culture) et du loisir, valeurs incarnées, bien que de façon controversées, dans le WEM. Pour établir les bases de la thèse principale, on examine les réinterprétations récentes du comportement hurnain avancées, dans les sciences humaines, par des chercheurs travaillant dans les domaines de ?interaction symbolique et la sociologie du savoir. Ces écoles ont engendré le concept, sinon le terme, de la religion fonctionelle. Le sens de ce terme est proche de celui de ?idéologie; une analyse comparative des deux termes justifie ?emploi du premier. Pour conclure la deuxièrne partie de ce mémoire, on passe en revue quelques écrits récents par des géographes qui abordent la religion ?un point de vue fonctionnel. De cet examen il ressort que le statut relative du travail et du loisir est ?une importance capitale. Dans la troisième partie, on présente une perspective sur le loisir qui est proche de celle qu'avancent Pieper, Huizinga, et de Grazia. Ceux-cisupportent la position des auteurs classiques, selon qui la vie humaine trouve sa signification dans les activités entreprises pour ellesměmes (par exemple, les jeux) plutǒt que pour le gain matériel. Appuyant leur argument, et m'opposant à celui des marxistes et des libéraux, je prétends que ?adoption du loisir comme vaieur fondamentale fournirait une meilleure assise à notre culture que celle offerte jusqu'ici par le travail. 相似文献
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20.
Among the manifestations of radioactive decay which can be etched to optical visibility on the surface of mica are tracks from nuclei recoiling from alpha emission, called ‘alpha-recoil tracks’. If, beforeetching, the mica is heated to temperatures of the order of 600°C, all evidence of these tracks is annealed from muscovite mica in a few minutes. Alpha activity observed on mica from pot sherds, from stones surrounding fire places, from fire pits, and fired daub may constitute an alpha-recoil track clock which started at the moment of the last firing of the artifacts. 相似文献