Effects of Different Record Selection Methods on the Transverse Seismic Response of a Bridge in South Western British Columbia

The seismic response of a continuous 4-span bridge designed according to the current Canadian seismic provisions is investigated using Incremental Dynamic Analysis (IDA). Different earthquake types, including shallow crustal events, interface Cascadia subduction, and deep inslab subduction are considered. The median collapse capacities calculated using different record selection methods including Conditional Mean Spectrum (CMS)-based, Uniform Hazard Spectrum (UHS)-based, and epsilon-based methods are compared. The use of the epsilon-based method generally resulted in the highest collapse capacity predictions, but the CMS-based method was less sensitive to the number of records considered in the IDA.     

Using an Evolutionary Algorithm in Multiobjective Geographic Analysis for Land Use Allocation and Decision Supporting

Usually, allocation of resources is an optimization problem which involves a variety of conflicting economic, social, and ecological objectives. In such a process, advanced geographic analyst tool for manipulation of spatial data and satisfaction of multiple objectives is essential to the success of decision‐making. The present research intends to demonstrate the application of a multiobjective optimization method based on NSGA‐II 1 (we call it HNSGA‐II), along with Geographical Information System (GIS) 2 to select suitable sites for the establishment of large industrial units. Having defined the elements of HNSGA‐II for the site selection of industrial units, the method is tested on the data of Zanjan province, Iran, as the case study. The results showed that the proposed approach can easily find a variety of optimized solutions, giving the decision‐makers the possibility to opt for the most propitious solution. Using this method, the achievement level regarding each objective function can be studied for any of the nondominated solutions.     

Investigating cultural evolution through biological phylogenetic analyses of Turkmen textiles

The debate on the evolution of culture has focused on two processes in particular, phylogenesis and ethnogenesis. Recently, it has been suggested that the latter has probably always been more significant than the former. This proposal was assessed by applying cladistic methods of phylogenetic reconstruction to a data set comprising decorative characters from textiles produced by Turkmen tribes since the 18th century. The analyses focused on two periods in Turkmen history: the era in which most Turkmen practised nomadic pastoralism and were organised according to indigenous structures of affiliation and leadership; and the period following their defeat by Tsarist Russia in 1881, which is associated with the sedentarisation of nomadic Turkmen and their increasing dependence on the market. The results indicate that phylogenesis was the dominant process in the evolution of Turkmen carpet designs prior to the annexation of their territories, accounting for c.70% of the resemblances among the woven assemblages. The analyses also show that phylogenesis was the dominant process after 1881, although ethnogenesis accounted for an additional 10% of the resemblances among the assemblages. These results do not support the proposition that ethnogenesis has always been a more significant process in cultural evolution than phylogenesis.     

Seismic Response of Bridges Subjected to Different Earthquake Types Using IDA

Incremental Dynamic Analysis (IDA) was used to evaluate the seismic response of straight, continuous 4-span bridges with different sub-structure configurations. Three different record sets were chosen to represent three different earthquake types which can occur for a site such as Vancouver (i.e., crustal, subduction interface, and subduction inslab earthquakes). Seventy eight records were considered in each set (i.e., a total of 234 records) and the capacities of the bridges were evaluated using a fast IDA algorithm. A simplified method to account for the effects of spectral shapes was used. Different subsets of the records with specific characteristics were also used in the IDA. The bridges were designed and evaluated for two different design force modification factors and bridges with different degrees of irregularity were studied. Comparisons of the IDA results obtained indicated that in most of the cases the interface record sets resulted in lower median collapse capacities and hence were the most critical of the ground motions studied.