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EXCAVATION OF THE 500 sq. m. waterfront site at Trig Lane in the City of London revealed a well-preserved series of timber and stone revetments on the medieval foreshore. They survived to heights of up to 3 m. and had been erected during the piecemeal reclamation and subsequent consolidation of the riverfront between the mid 13th and late 15th century.

The structures are described in detail, and their form and function discussed. Ninety-four oak samples were submitted for dendrochronological analysis, the results of which enabled a relative chronology for part of the revetment sequence to be established and absolute dates postulated.  相似文献   
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BUILDING ACCOUNTS for 1398–99 give detailed costs of the construction of a circular, brick, free-standing artillery tower. The artillery towers at Southampton and Canterbury were linked to existing wall circuits, and detached forts in France may be more comparable to the tower at Norwich.  相似文献   
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Abstract

The collapse of empires is exceedingly difficult to understand. The author examined the distribution of imperial lifetimes using a data set that spans more than three millennia and found that it conforms to a memoryless exponential distribution in which the rate of collapse of an empire is independent of its age. Comparing this distribution to similar lifetime distributions of other complex systems—specifically, biological species and corporate firms—the author explores the reasons behind their lifetime distributions and how this approach can yield insights into empires.  相似文献   
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The changing dynamics of regional and local labor markets during the last decades have led to an increasing labor market segmentation and socioeconomic polarization and to a rise of income inequalities at the regional, urban, and intraurban level. These problems call for effective social and local labor market policies. However, there is also a growing need for methods and techniques capable of efficiently estimating the likely impact of social and economic change at the local level. For example, the common methodologies for estimating the impacts of large firm openings or closures operate at the regional level. The best of these models disaggregate the region to the city (Armstrong 1993; Batey and Madden 1983). This paper demonstrates how spatial microsimulation modeling techniques can be used for local labor market analysis and policy evaluation to assess these impacts (and their multiplier effects) at the local level‐to measure the effects on individuals and their neighborhood services. First, we review these traditional macroscale and mesoscale regional modeling approaches to urban and regional policy analysis and we illustrate their merits and limitations. Then, we examine the potential of spatial microsimulation modeling to create a new framework for the formulation, analysis and evaluation of social and local labor market policies at the individual or household level. Outputs from a local labor market microsimulation model for Leeds are presented. We show how first it is possible to investigate the interdependencies between individual's or households labor market attributes at the microscale and to model their accessibilities to job opportunities in different localities. From this base we show how detailed what‐if microspatial analysis can be performed to estimate the impact of major changes in the local labor market through job losses or gains, including local multiplier effects.  相似文献   
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