Seismic Tests and Numerical Modeling of a Rolling-ball Isolation System

For the seismic isolation of light structures, the use of laminated rubber bearings is neither economical nor, for most cases, technically suited. For the isolation of this type of structure a new system, consisting of steel balls rolling on rubber tracks, has been developed at TARRC (Tun Abdul Razak Research Centre).

This article presents the results of experimental tests carried out for the characterization of the behavior of this new device. A numerical model is also proposed that can be used to assess the seismic response of structures with this isolation system.

Comparison of the predictions of the numerical model with the experimental data shows that the model is adequate to perform the correct assessment of the seismic response of isolated structures. The results of the experimental campaign of shaking-table tests, as well as the numerical simulations, show that there is an effective reduction of the acceleration levels induced in the isolated structures.     

Why does child trafficking policy need to be reformed? The moral economy of children's movement in Benin and Ethiopia

This paper challenges policy discourses that frame children's independent movement as intrinsically exploitative and threatening to their development. Drawing on research with children and adults in Benin and Ethiopia, two countries caught up in current efforts to eradicate child migration and the trafficking with which it has become associated, the paper critiques assumptions about children's vulnerability and physical dependence and contests the idea that appropriate childhood is necessarily fixed spatially within stable family structures. It, thus, situates children's migration within socio-cultural and economic contexts and suggests that it should be understood as part of a moral economy that confounds simplistic paradigms that conflate migration with trafficking. Policy suggestions are offered for how best to secure children's well-being through acknowledgement of the important relationship between mobility and child maturation.     

On the Architecture of the Abbey Church of Dorchester

During 1984 and 1985 an area of over 1500 sq. m was excavated on Hartlepool Headland (NZ 528 336) by Cleveland County Archaeology Section. The results of this work will be presented in two parts, the Anglo-Saxon first, followed by the Medieval in a later volume of the Journal.

The excavations revealed two periods of Anglo-Saxon occupation, defined by a change from earthfast to free-standing structures. The earlier period, of earthfast construction, has been divided into four phases ranging in date from the mid seventh century to the first quarter of the eighth Century. Associated with the earlier period was a boundary complex of two phases of construction. This has been interpreted as a ‘vallum monasterii’. The backfill of the boundary was radiocarbon dated to c. ad 690 and contained metalworking moulds and crucibles. The latter included three decorated pieces which have added materially to the knowledge of early Northumbrian art and metalworking.

The later period of occupation saw the construction of free-standing, stone-footed structures. In some cases the footings had been inserted into earthfast structures of the earlier period. This site is interpreted as part of the Anglo-Saxon double monastery of ‘Heruteu’, comprising an area of workshops and living quarters. Occupation ceased in the last quarter of the eighth century.     

Archaeology as diachronic anthropology

Fred T. Plog. The Study of Prehistoric Culture Change. New York: Academic Press, 1974. xii + 199 pp. Figures, tables, appendices, references, and index. $11.50.