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A numerical and experimental study of the collapse and energy absorption behavior of thin-walled end capped conical shells under dynamic loading is presented in this paper. Among the structural components, the truncated conical shells whose energy absorption characteristics are better than others are used. In order to carry out the designed tests, a drop hammer machine has been used. Also in numerical part, Abaqus software capabilities have been applied. In this article, the effect of the velocity and mass of the hammer on the collapse behavior of these samples has been investigated. Moreover, by placing the cone reversely, the force effect on the collapse behavior evaluated and analyzed. Also, the multiple sets of cones as energy absorbing system are analyzed numerically. For the samples, mode of collapse of diamond with quadrilateral pattern was obtained and a very good agreement with experimental results was recorded. The results shows that the change of wall thickness has the most influence on the collapse behavior of these shells. So that with a 20% reduction of shell thickness, maximum force had 34.5% and the average force collapse 39.3% reduction.

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Introduction: Global competitiveness is the name of the game of our time, and in today's world, competitiveness has become a fundamental force in the urban economy, just like gravity in physics. Today, the competitiveness of cities plays an essential role in the development of cities. Competitiveness arises from a combination of assets and processes. Assets are either a gift, such as natural resources or man-made resources, such as city infrastructure and processes that turn assets into economic benefits for cities and ultimately make them more competitive. With the formation of globalization and networking of the global economy, cities have always found a special place as nodes of network economy, and it is believed that this competition is on a par with national competition.