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A recursive model of the spatial allocation of migrants   总被引:1,自引:0,他引:1  
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Fifty-one waster sherds of Terra Sigillata (~20-0 b.c. ) from Arezzo, Italy and Lyons, France have been chemically analysed for twenty-eight elements by neutron activation and seven by X-ray fluorescence. Most of the elemental abundances were measured with high precision and cross-comparisons of the two techniques of measurement (and sample preparation) give added insight as to their relative precision, the calibration differences and the extent to which volatile materials such as carbonate or water influence the results. The sherds from Arezzo formed a homogeneous and distinctive chemical group while all but two of those from Lyons were classified into three such groups. Two of the Lyons groups (MML A and MML B) were from Montée de La Muette and one was from Loyasse. Four additional sherds from houses excavated in Strasbourg and one from Lyons, all of which bore the signature of the famous Anetine pottery-making firm of Ateius, were also analyzed by the same techniques. These signed sherds all had the same composition pattern and it closely matched one of those from Montée de La Muette (MML A) in Lyons. It is therefore suggested that these five sherds bearing the Ateius signature were made in the general vicinity of Lyons and were part of the output of an as yet unknown Gallic branch of the firm of Ateius.  相似文献   
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Theoretical values for spacing between points of the Poisson process are frequently used to evaluate the hypothesis that the locations within a region of pointlike objects have a random pattern. These theoretical spacing values are an approximation to spacing values for a uniform process in which the objects are uniformly and independently located in the region. The adequacy of the Poisson approximation to this uniform process for a square region is evaluated by analytic and numeric methods. The approximation is close for a small number of points when spacing between objects is measured by toroidal distance.  相似文献   
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It is proposed that two-dimensional displays, such as maps, aerial photographs, polygons, etc., may be generated and/or described by two-dimensional languages. A simple perceptual device is posited which utilizes such a language. The device is comprised of at least two components which represent short-term and long-term memory. It is clear that its conceputal locus is in multisystem memory models. Three such models are characterized which provide the necessary and sufficient conditions for the perceptual model posited. Given this conceptual frame, three illustrative sets of implications and experiments for human responses to two-dimensional displays are suggested.  相似文献   
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BOOK REVIEWS     
Book Reviews in This Article:
Der Koran. Ed. by Rudi Paret.
Introduction to Classical Arabic Literature. By Ilse Lichtenstadter.
On the Art of Medieval Arabic Literature. By Andras Hamori.
Four Egyptian Literary Critics. By David Semah.
Hispano-Arabic Strophlc Poetry. Studies by Samuel Miklos Stern.
The Hamadsha: A Study in Moroccan Ethnopsychiatry. By Vincent Crapanzano.
Publish it not… The Middle East Cover-up. By Christopher Mayhew and Michael Adams.
From Ottomanism to Arabism: Essays on the Origins of Arab Nationalism. By C. Ernest Dawn.
An Inquiry into the Ethnography of Afghanistan. By Henry W. Bellew.  相似文献   
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