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981.
982.
Magnetic and other measurements are reported for the Guehenno II Gallo-Roman hoard (56-France) which, amongst several thousand Tetricus antoniniani, contains 275 coins struck with the same dies. The orientation of the remanent magnetization is systematically directed outwards from the obverse confirming the identity of the anvil die with the obverse. The magnetization vector is statistically distributed around the vertical axis giving no indication of the geomagnetic inclination at the time of striking. Consequently ancient struck coins cannot be used for dating. The origin of the remanent magnetization was also investigated. 相似文献
983.
L. T. RUNIA 《Archaeometry》1987,29(2):221-232
Bones from a Bronze Age settlement in a low-lying area in The Netherlands were analysed for their content of strontium and certain other elements. Low strontium concentrations in the human bones indicate that part of the diet consisted of animal products. Milk and dairy products were probably also incorporated in the diet. This would have had a marked effect on the Sr/Ca ratio of the total diet and on the strontium content of human bones. Anomalous mean strontium concentrations for the animal species are tentatively explained in relation to the specific environment of the settlement. Different pasturing practices for cattle and sheep/goat respectively are possibly reflected by the strontium content of their bones. 相似文献
984.
985.
986.
987.
Forty-five sherds of Roman pottery, 21 terrae sigillutae and 24 common wares excavated in Augusta Praeroria, were analysed for 12 elements by atomic absorption and emission spectroscopy. Hierarchical agglomerative cluster analysis, principal component analysis, and non-linear mapping were performed on the analytical data in order to classify the objects in groups which could account for different provenances; soft independent modelling of class analogy (SIMCA) and K nearest neighbours (KNN) were used for solving doubtful assignments. The classification results indicate that local productions of terra sigillatu can be easily distinguished from the imported ones, and that common wares have compositional patterns which differ from those of both local and imported terrae sigillatue. 相似文献
988.
989.
Richard L. Church 《Geographical analysis》1990,22(1):22-32
In many applications involving the location of public facilities, the activity that is being located is added to the landscape of existing public facilities and services. Further, there also exists a political and behavioral landscape of differing jurisdictions, representations, and perceptions. This paper presents a new form of the p-median problem which addresses two types of “regional” constraints that can arise in public facilities planning. A formulation is given for this specially constrained median problem along with a solution approach. Several examples are presented with computational results which indicate that this type of constrained problem could lead to better facilities planning. 相似文献
990.
Little evidence is currently available on the regional growth effects of federal defense spending. In this study, econometric models for state personal income and manufacturing employment between 1976 and 1985 are specified and estimated. Pooled cross-sectional time-series data are used, and the estimation procedure corrects for serial correlation, heteroscedasticity, and contemporaneous cross-sectional correlation. The results indicate that aggregate defense spending has a positive effect on both growth measures. However, when defense expenditures are disaggregated, only investment-type outlays appear to consistently affect state economic growth. 相似文献