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991.
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
992.
993.
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
994.
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
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Ingrid L. Mainland 《Journal of archaeological science》1998,25(12):1259-1271
In recent years, dental microwear analysis has attracted considerable interest as a potential method for reconstructing ancient diet. This article presents results from research exploring the potential of dental microwear analysis in the reconstruction of domestic ungulate diet through the quantitative analysis of diet-microwear relationships in modern grazing and fodder-fed sheep and goats. Diet-related microwear patterning is identified in the modern populations examined and it is concluded that with investigation of a wider range of modern diets, dental microwear analysis will emerge as a valuable and insightful approach for the investigation of diet in ancient livestock. 相似文献
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