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991.
Books reviewed in this article:
John Hines, Karen Høilund Nielsen and Frank Siegmund (eds), The Pace of Change. Studies in Early–Medieval Chronology.
Catherine E. Karkov, Kelley M. Wickham–Crowley and Bailey K. Young (eds), Spaces of the Living and the Dead: An Archaeological Dialogue.
Sam Lucy, The Early Anglo–Saxon Cemeteries of East Yorkshire. An Analysis and Reinterpretation.
Elizabeth O'Brien, Post–Roman Britain to Anglo–Saxon England: Burial Practices Reviewed.
Nick Stoodley, The Spindle and the Spear. A Critical Enquiry into the Construction and Meaning of Gender in the Early Anglo–Saxon Burial Rite.  相似文献   
992.
This essay examines a 1968–9 campaign by Tanzania’s ruling party Youth League to outlaw mini–skirts and other ‘indecent’ fashions as ‘decadent’ affronts to Tanzanian ‘national culture’. It situates the intense, public debate on the campaign both in terms of the state’s contested national cultural project, and in relation to intersecting anxieties about shifts in women’s work and mobility in urban space, and the politics of sex in postcolonial Dar es Salaam. Arguing that ‘the city’ ndash; both as an imagined space and as the site of particular, gendered social struggles – is central to understanding the campaign, the essay charts attempts by the ban’s opponents to fashion viable personas and notes the limits of these attempts.  相似文献   
993.
Using a set of interregional input‐output tables built by Guilhoto (1998) for 1995 for two Brazilian regions (Northeast and rest of the economy), the methodology developed by Sonis, Hewings, and Miyazawa (1997) is applied in the construction of a series of linkages such that it is possible to examine, through the nature of the internal and external interdependencies, the structure of trading relationships between the two regions. The methodology uses a partitioned input‐output system and exploits techniques that produce left and right matrix multipliers of the Leontief Inverse. This procedure facilitates the classification of the types of synergetic interactions within a preset pairwise hierarchy of economic linkages subsystems. In general, the results show that the Northeast region has a greater dependence on the rest of the economy region than the rest of the economy has on the Northeast region, and at the same time the rest of the economy region seems to be more developed as it presents a more complex productive structure than the Northeast region.  相似文献   
994.
The land acquisition problem is a spatial partitioning problem that involves selecting multiple parcels to be acquired for a particular land use. Three selection criteria are considered: total cost, total area, and spatial contiguity. Achieving contiguity or connectivity has been problematic in previous exact methods for land acquisition. Here we present a new zero‐one programming model that enforces necessary and sufficient conditions for achieving contiguity in discrete cell landscapes, independent of other spatial attributes such as compactness. Computational experience with several demonstration problems is reported, and results and extensions are discussed.  相似文献   
995.
The analysis by nuclear activation techniques and by inductively coupled plasma mass spectrometry combined with an UV laser of a large number of gold coins issued in the Arab Empire from the seventh to the 12th century ad showed that several different supplying sources were used, according to the region and to the period. The aim of this paper is to point out the circulation of gold in the Near and Middle Eastern mints of the Arab Empire and to make a parallel with the mints’ policies running in the other regions of the Empire, such as North Africa, the Iberian Peninsula and the Sicily. The identification of different gold ores by means of characteristic trace elements indicated recycling of the ancient coinage and, after ad 750, the minting in the entire Arab Empire of different new gold ores: Egyptian type, North Eastern type and West African type. The analysis of a small number of silver coins from the same periods and regions also showed a change in the ore supply after ad 750.  相似文献   
996.
This article reviews recent archaeological research on warfare in prestate societies of native North America. This survey comprises six regions: Arctic/Subarctic, Northwest Coast, California, Southwest/Great Basin, Great Plains, and Eastern Woodlands. Two lines of evidence, defensive settlement behavior and injuries in human skeletal remains, figure prominently in archaeological reconstructions of violence and warfare in these regions. Burning of sites and settlements also has been important for identifying the consequences of war and investigating more subtle aspects of strategy and directionality. Weaponry and iconography have to date provided important but more limited insights. Although considerable disparities exist between regions in the archaeological evidence for intra- and intergroup violence, all regions show a marked increase after A.D. 1000. These findings suggest that larger forces may have been responsible for escalating violence throughout North America at this time.  相似文献   
997.
998.
999.
The First World War polarised British society. The British 'nation' needed a definition of the external enemy to generate internal cohesion as much as the production of modern hostility presupposed the existence of nationalism. Apparently, hostility which is nationalistically motivated is of functional importance for the cohesion of a society in war. But the construction of the nation along the lines of the dialectic structure of exclusion and inclusion implies that even its founding act encourages national splits. The manner in which nationalism generates social cohesion by excluding non-members at the same time always turns it into the expression of and the reason for internal conflicts. First and foremost, however, it was the co-existence of a whole host of concepts of the nation competing with each other for supremacy which turned nationalism into a disintegrative power in society. The co-existing national concepts by and large reflected the political factions and camps in the belligerent society. This article tries to outline the various ways in which the borderlines between the internal and the external enemy, between the hostile part of one's own society and a hostile foreign society converged under the circumstances of the exceptional burden of the First World War. At the end the hostility which was motivated and legitimised nationalistically both split and integrated British society.  相似文献   
1000.
Gas breakthrough experiments on fine-grained sedimentary rocks   总被引:1,自引:0,他引:1  
The capillary sealing efficiency of fine‐grained sedimentary rocks has been investigated by gas breakthrough experiments on fully water saturated claystones and siltstones (Boom Clay from Belgium, Opalinus Clay from Switzerland and Tertiary mudstone from offshore Norway) of different lithological compositions. Sand contents of the samples were consistently below 12%, major clay minerals were illite and smectite. Porosities determined by mercury injection lay between 10 and 30% while specific surface areas determined by nitrogen adsorption (BET method) ranged from 20 to 48 m2 g ? 1. Total organic carbon contents were below 2%. Prior to the gas breakthrough experiments the absolute (single phase) permeability (kabs) of the samples was determined by steady state flow tests with water or NaCl brine. The kabs values ranged between 3 and 550 nDarcy (3 × 10?21 and 5.5 × 10?19 m2). The maximum effective permeability to the gas‐phase (keff) measured after gas breakthrough on initially water‐saturated samples extended from 0.01 nDarcy (1 × 10?23 m2) up to 1100 nDarcy (1.1 × 10?18 m2). The residual differential pressures after re‐imbibition of the water phase, referred to as the ‘minimum capillary displacement pressures’ (Pd), ranged from 0.06 to 6.7 MPa. During the re‐imbibition process the effective permeability to the gas phase decreases with decreasing differential pressure. The recorded permeability/pressure data were used to derive the pore size distribution (mostly between 8 and 60 nm) and the transport porosity of the conducting pore system (10‐5–10‐2%). Correlations could be established between (i) absolute permeability coefficients and the maximum effective permeability coefficients and (ii) effective or absolute permeability coefficients and capillary sealing efficiency. No correlation was found between the capillary displacement pressures determined from gas breakthrough experiments and those derived theoretically by mercury injection.  相似文献   
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